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  • Skott, Anton
    Linköpings universitet, Institutionen för kultur och samhälle, Avdelningen för filosofi, historia, konst och religion.
    Problems and Possibilities with Non-Empirical Assessment of Scientific Theories: An Analysis of the Argument Given by Richard Dawid2020Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This essay examines the argument given by Richard Dawid (2013, 2019) for the viability of non-empirical assessment of scientific theories. Dawid's argument is supposed to show that trust in a scientific theory can be justified without any direct empirical testing of the theory. This view is fundamentally different from what will be called the classical paradigm of theory assessment. The classical paradigm holds that only empirical testing can justify belief in a theory. It is argued in this essay that Dawid's argument does not provide sufficient reasons for claiming that non-empirical assessment can be seen as a valid form of justification of scientific theories. However, it is further argued that non-empirical assessment still can play an important role when evaluating the status of a theory that cannot yet be tested empirically.

  • Bäckström, Anna
    et al.
    Linköpings universitet, Institutionen för beteendevetenskap och lärande. Linköpings universitet, Utbildningsvetenskap.
    Johansson, Katarina
    Linköpings universitet, Institutionen för beteendevetenskap och lärande. Linköpings universitet, Utbildningsvetenskap.
    Lärares erfarenhet av och kunskap om "poor comprehenders": - Specifika förståelsesvårigheter2020Självständigt arbete på avancerad nivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Syftet med vår kvalitativa studie är att bidra med ökad kunskap om vilken erfarenhet och kunskap lärare som arbetar på mellanstadiet har om poor comprehenders. Vi vill även bidra med ökad kunskap om på vilka sätt elever med dessa svårigheter upptäcks och hur det kan påverka undervisningens utformning. Vi har genomfört semistrukturerade intervjuer med 12 lärare som undervisar eller har undervisat på mellanstadiet. Efter att ha gjort en tematisk analys av vårt material fann vi fem teman som belyser lärares kunskap om och erfarenhet av poor comprehenders samt hur undervisningen utformas och anpassas med tanke på dessa elever. Resultatet visar att begreppet poor comprehenders är okänt bland lärare men fenomenet väl känt. Poor comprehenders upptäcks ofta i klassrumsundervisningen. Kartläggning av läsförståelse sker på alla skolorna i vår studie men hur man dokumenterar och använder resultaten varierar, liksom hur undervisningen utformas och anpassas. En slutsats är att avsaknaden på ett vedertaget begrepp gör att det kan vara svårt att kommunicera runt den här gruppen av elever. En annan slutsats är att det inte finns någon tydlig definition av problematiken, vilket i sin tur kan leda till att kunskapen varierar i hur man bäst utformar undervisningen för att utveckla lärandet för poor comprehenders. Det finns en stor variation i graden av erfarenhet av att arbeta med förståelseproblematik.  

  • Bergnér, Angelika
    et al.
    Linköpings universitet, Institutionen för beteendevetenskap och lärande. Linköpings universitet, Utbildningsvetenskap.
    Almkvist, Tove
    Linköpings universitet, Institutionen för beteendevetenskap och lärande. Linköpings universitet, Utbildningsvetenskap.
    En interventionsstudie i subtraktion inom talområdet 0 - 20 utifrån explicit undervisning.: Effekter av undervisning i huvudräkningsstrategier inom RtI nivå 1 för elever i årskurs sex.2020Självständigt arbete på avancerad nivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Grundläggande kunskaper i aritmetik är centralt inom matematiken och effektiva strategier samt kontinuerlig övning gynnar alla elever.

    Arbetet syftade till att utforma och pröva om en helklassintervention, RtI nivå ett, inom grundläggande aritmetik gav effekt. Interventionen genomfördes under tre veckor i två årskurs sexklasser som fick undervisning i korta pass tre gånger per vecka. Undervisningen strukturerades utifrån explicit undervisning och CRA-metoden där undervisningen börjar på konkret nivå övergår i representativ och slutligen i abstrakt nivå. Eleverna fick undervisning i olika strategier för huvudräkning inom subtraktion samt möjlighet att öva huvudräkning inom subtraktion i talområdet 0 - 20.

    Studien var ett kvasiexperiment med förtest och eftertest i både interventionsgrupperna och kontrollgrupperna. En statistisk signifikant effekt kunde mätas då interventionsgruppens medelvärde förbättrades mer än kontrollgruppens inom huvudräkningstestet. Ingen transeffekt uppmättes för algoritmräkning inom subtraktion.

  • Bengtsson, Sara
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Affärsrätt. Linköpings universitet, Filosofiska fakulteten.
    Roos, Sigrid
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Affärsrätt. Linköpings universitet, Filosofiska fakulteten.
    Förbudsklausuler i aktieägaravtal: När används förbudsklausuler, vilka risker finns och hur hanteras riskerna?2019Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I denna uppsats behandlas förbudsklausuler i aktieägaravtal. Med förbudsklausuler avses en reglering som medför att det inte är tillåtet att överlåta aktier, vilket således inskränker i principen om aktiers fria överlåtelse. Var gränsen går mellan vad som är att anse en tillåten förbudsklausul och inte tillåten förbudsklausul är inte helt klar. I uppsatsen skildras i vilka situationer förbudsklausuler kan tänkas vara lämpliga och vilka omständigheter som påverkar hur en förbudsklausul utformas. För att utreda när en förbudsklausul kan vara lämplig inleds uppsatsen med en redogörelse för vad ett aktieägaravtal i grunden är, vilka som normalt är avtalsparter i aktieägaravtal och vilka allmänna avtalsrättsliga principer det finns att förhålla sig till. I uppsatsen berörs även vilka aktiebolagsrättsliga regler som påverkar utformningen av ett aktieägaravtal. För att utreda uppsatsens frågeställningar används dels doktrin som finns inom ämnet aktieägaravtal, dels empiriskt material i form av intervjuer med jurister och advokater som har praktisk erfarenhet. I och med detta vägs både inställningen som framhålls i doktrin och praktiserande juristers inställning till förbudsklausuler in i bedömningen.

    Vi utreder även vilka risker som finns med förbudsklausuler och hur riskerna lämpligen bör behandlas för att förbudsklausuler inte ska riskera att jämkas eller ogiltigförklaras vid tillämpning av 36 § lagen (1915:218) om avtal och andra rättshandlingar på förmögenhetsrättens område, nedan kallat AvtL eller avtalslagen, på grund av inskränkning i aktiers fria överlåtelse. För att bedöma var gränsen går samt utreda i vilka situationer det skulle vara möjligt att använda sig av generalklausulen i 36 § AvtL, framställs även en redogörelse av vilka omständigheter domstolarna tar särskild hänsyn till vid tillämpning av generalklausulen. Vilka risker som finns med förbudsklausuler beror delvis på vilken situation som avses och aktieägarnas inbördes relation. Av denna anledning hanteras riskerna med hänsyn till omständigheterna i den enskilda situationen. Slutligen görs en avvägning i vilka situationer det finns anledning att använda sig av förbudsklausuler i aktieägaravtal och vilken omfattning förbuden lämpligen bör ha.

  • Sjögren, Karin
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling. Linköpings universitet, Filosofiska fakulteten.
    “Att bli accepterad är långt ifrån samma sak som att bli vald”: – Hur inkludering av elever med funktionsnedsättning påverkar attityder och sociala relationer hos elever utan funktionsnedsättning2020Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Denna litteraturstudies syfte är att belysa hur inkluderingsarbetet av elever med funktionsnedsättning uppfattas av och påverkar elever utan funktionsnedsättning. För att skapa en bild av detta undersöks attityder och sociala relationer hos elever utan funktionsnedsättnings samt vad som avgör vilka attityder och relationer som uppstår i samband med inkludering. Uppsatsen använder sig av en kvalitativ innehållsanalys där en induktiv ansats antagits. Till detta har de sociologiska teorierna om stämpling, stigma och social identitetsteori använts för att fördjupa analysen. De vetenskapliga artiklar som valts beskriver studier som genomförts i ett flertal olika länder och haft fokus på inkludering och elever utan funktionsnedsättning. Studien visar att attityder hos elever utan funktionsnedsättning gentemot elever med funktionsnedsättning är övervägande negativa och att dessa göds av olika former av oförståelse och fördomar. Mindre förekommande är positiva attityder präglade av förståelse och acceptens, men de påträffas trots allt i vissa studier. Vidare visar resultatet att sociala relationer är avgörande sitt sammanhang. Elever utan funktionsnedsättning vill hellre umgås med elever med funktionsnedsättning på fritiden än i klassrummet där akademiskt samarbete krävs. Den vanligaste relationen är dock att inte ha någon relation alls. Vad som avgör vilka attityder och relationer som uppstår skiftar men viktiga faktorer är eleverna själva, lärarnas attityder och förmåga att arbeta inkluderande samt samhällsrelaterade faktorer som ekonomi, resurser och politik. Resultatet indikerar att det finns olika framgångsrika sätt att arbeta inkluderande i klassrummet och att vissa aspekter med fördel bör tas i beaktning för att uppnå ett så lyckat resultat som möjligt.

  • Disputation: 2020-05-14 13:00 Berzeliussalen, Building 463, LinköpingBeställ onlineKöp publikationen >>
    Åhlund, Kristina
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för prevention, rehabilitering och nära vård. Linköpings universitet, Medicinska fakulteten.
    Physical Fitness in Hospitalized Frail Elderly Patients2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Demographic research shows that the proportion of older people in society is increasing. More people age well, but there are also more people getting old with disability and multimorbidity. The large diversity in functioning illustrates the heterogeneity of aging. Accelerated aging may lead to frailty, which is a geriatric syndrome, often used as a marker of biologic age and associated with decreased physiologic reserves, increased vulnerability and the risk of adverse health out- comes. Frail elderly people are frequent visitors within emergency hospital care and physical decline is common. Unfortunately, elderly patients with substantial multimorbidity are often excluded from clinical trials.

    Physical fitness comprises a set of measurable health- and skill-related outcomes, such as cardiorespiratory endurance and muscle strength. A decrease in physical fitness may affect the prognosis negatively. However, previous research indicates that it may be possible to reverse frailty and improve physical fitness. It is therefore of the utmost interest to identify frailty and study how care is best provided, in order to prevent, reduce and postpone adverse health consequences.

    The overall aim of this thesis is to study physical fitness in a group of frail elderly patients, within clinical hospital health care. The patients’ physical fitness will be evaluated and compared in different care settings during and after hospitalization. The aim is also to study the long-term consequences of changes in physical fitness in relation to mortality. To better understand the underlying factors for partici- pation in physical activity and exercise, patients’ perceptions of the phenomena will be explored.

    This thesis consists of four papers based on two studies comprising frail elderly patients with substantial multimorbidity, in connection with an in-hospital episode.

    Paper 1 was an observational study with a cross-sectional design (n=408). Different components of physical fitness were measured during an index hospital stay and the results showed that hospitalized frail elderly patients performed below previously described age-related reference values. Furthermore, physical fitness was associated with the degree of frailty, rather than the chronological age.

    Paper 2 was a prospective controlled trial, with two parallel groups. The patients included in the intervention group (n=206) were cared for at an emergency medical care unit providing care according to Comprehensive Geriatric Assessment and care (CGA). The control group (n=202) was cared for at conventional emergency medical care units. The multi-professional care approach at the CGA unit was shown to be beneficial, in terms of a greater proportion of patients who preserved or improved their function during the first three months after discharge from hospital, compared with conventional care.

    Paper 3 had a prospective approach when evaluating the association between physical fitness and oneyear mortality in those 390 patients discharged alive from a hospital care episode. The results showed that physical fitness during in-hospital care and the change in physical fitness during the first months after discharge were associated with one-year mortality.

    In Paper 4, the patients’ perspective in terms of physical activity and exercise was explored. The theme of “Meaningfulness and risk of harm in an aging body” emerged, followed by the three categories of physical activity as part of daily life, goals of physical activity and exercise and prerequisites for physical activity and exercise.

    These studies highlight the importance of a greater focus on physical fitness in hospitalized elderly patients. A careful assessment and a multi-professional approach may lead to beneficial results and better survival even in a group of frail elderly patients with severe multimorbidity. To increase physical activity and exercise in this group of patients, health care probably needs to improve the means of communicating the benefits and goals of exercise and facilitating them so that the risk of harm is reduced.  

    Delarbeten
    1. Physical Performance Impairments and Limitations Among Hospitalized Frail Older Adults
    Öppna denna publikation i ny flik eller fönster >>Physical Performance Impairments and Limitations Among Hospitalized Frail Older Adults
    2018 (Engelska)Ingår i: Journal of Geriatric Physical Therapy, ISSN 1539-8412, E-ISSN 2152-0895, Vol. 41, nr 4, s. 230-235Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Background and purpose: Early rehabilitation is important for frail older adults due to reduced reserve capacity and physical fitness. To facilitate individualized rehabilitation programs, we need tools to make it possible to assess physical fitness in relation to frailty, instead of chronological age. The purpose of this study was, in a Swedish context, to describe measures of physical fitness in hospitalized frail older adults in relation to their degree of frailty. Methods: This was a cross-sectional study. A total of 408 frail older adults, mean age 86.6 years (75-99 years), in need of emergency medical inpatient care, were included in the NAL-Uddevalla (NU) hospital group in Sweden. During the hospital stay, physical fitness was assessed using 4 different tests: hand-grip strength, the Timed Up and Go Test, 5-time sit-to-stand test, and 6-minute walk test. In the analyses, the physical fitness outcomes were related to the degree of frailty using the FRail Elderly Support ResearcH group screening instrument and previously used cutoffs or age-related reference values for older adults. Results and Discussion: This study showed that most hospitalized frail older adults perform far lower than previously described age-related reference values relating to physical fitness. An increased degree of frailty contributes to reduced physical fitness in tests assessing strength and endurance. Conclusions: A frail-related screening instrument may be useful in the evaluation of physical fitness in hospitalized frail older adults and may facilitate the development of realistic, individualized rehabilitation programs beneficial to an early start on the emergency medical ward.

    Ort, förlag, år, upplaga, sidor
    LIPPINCOTT WILLIAMS & WILKINS, 2018
    Nyckelord
    emergency medical care; frailty; physical fitness; physical therapy
    Nationell ämneskategori
    Geriatrik
    Identifikatorer
    urn:nbn:se:liu:diva-153391 (URN)10.1519/JPT.0000000000000127 (DOI)000450885400006 ()28252472 (PubMedID)
    Anmärkning

    Funding Agencies|NU Hospital Group, Department of Research and Development

    Tillgänglig från: 2018-12-17 Skapad: 2018-12-17 Senast uppdaterad: 2020-04-07
    2. Effects of comprehensive geriatric assessment on physical fitness in an acute medical setting for frail elderly patients
    Öppna denna publikation i ny flik eller fönster >>Effects of comprehensive geriatric assessment on physical fitness in an acute medical setting for frail elderly patients
    2017 (Engelska)Ingår i: Clinical Interventions in Aging, ISSN 1176-9092, E-ISSN 1178-1998, Vol. 12, s. 1929-1939Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Introduction: Frail elderly people often use emergency care. During hospitalization, physical decline is common, implying an increased risk of adverse health outcomes. Comprehensive Geriatric Assessment (CGA) has been shown to be beneficial for these patients in hospital care. However, there is very limited evidence about the effects on physical fitness. The aim was to compare effects on physical fitness in the acute care of frail elderly patients at a CGA unit versus conventional care, 3 months after discharge. Patients and methods: A clinical, prospective, controlled trial with two parallel groups was conducted. Patients aged $ 75 years, assessed as frail and in need of inpatient care, were assigned to a CGA unit or conventional care. Measurements of physical fitness, including handgrip strength (HS), timed up-and-go (TUG), and the 6-minute walk test (6-MWT) were made twice, at the hospital index care period and at the 3-month follow-up. Data were analyzed as the mean change from index to the 3-month follow-up, and dichotomized as decline versus stability/improvement in physical fitness. Results: In all, 408 participants, aged 85.7 +/- 5.4 years, were included. The intervention group improved significantly in all components of physical fitness. The controls improved in TUG and declined in HS and 6-MWT. When the changes were dichotomized the intervention group declined to a lesser extent; HS pamp;lt;0.001, 6-MWT pamp;lt;0.001, TUG pamp;lt;0.003. The regression analysis showed the following odds ratios (ORs) for how these outcomes were influenced by the intervention; HS OR 4.4 (confidence interval [CI] 95% 2.2-9.1), 6-MWT OR 13.9 (CI 95% 4.2-46.2), and TUG OR 2.5 (CI 95% 1.1-5.4). Conclusion: This study indicates that the acute care of frail elderly patients at a CGA unit is superior to conventional care in terms of preserving physical fitness at 3 months follow-up. CGA management may positively influence outcomes of great importance for these patients, such as mobility, strength, and endurance.

    Ort, förlag, år, upplaga, sidor
    DOVE MEDICAL PRESS LTD, 2017
    Nyckelord
    frail elderly; comprehensive geriatric assessment; physical fitness; outcomes
    Nationell ämneskategori
    Geriatrik
    Identifikatorer
    urn:nbn:se:liu:diva-143250 (URN)10.2147/CIA.S149665 (DOI)000415128600002 ()
    Anmärkning

    Funding Agencies|NU Hospital Group, Department of Research and Development

    Tillgänglig från: 2017-11-27 Skapad: 2017-11-27 Senast uppdaterad: 2020-04-07
    3. Preserved physical fitness is associated with lower 1-year mortality in frail elderly patients with a severe comorbidity burden
    Öppna denna publikation i ny flik eller fönster >>Preserved physical fitness is associated with lower 1-year mortality in frail elderly patients with a severe comorbidity burden
    Visa övriga...
    2019 (Engelska)Ingår i: Clinical Interventions in Aging, ISSN 1176-9092, E-ISSN 1178-1998, Vol. 14, s. 577-586Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Introduction: Physical deterioration in connection with a care episode is common. The aim of this study was, in frail elderly patients with a severe comorbidity burden, to analyze 1) the association between physical fitness measurements and 1-year mortality and 2) the association between preserved physical fitness during the first three months after discharge from emergency hospital care and 1-year prognosis.

    Methods: Frail elderly patients (≥75 years) in need of inpatient emergency medical care were included. Aerobic capacity (six-minute walk test, 6MWT) and muscle strength (handgrip strength test, HS) were assessed during the hospital stay and at a three-month follow-up. The results were analyzed using multivariate Cox regression; 1) 0–12-month analysis and 2) 0–3-month change in physical fitness in relation to 1-year mortality. The analyses were adjusted for age, gender, comorbidity and frailty.

    Results: This study comprised 408 frail elderly hospitalized patients of whom 390 were evaluable (mean age 85.7 years, Charlson’s index mean 6.8). The three-month mortality was 11.5% and the 1-year mortality was 37.9%. After adjustments, the Cox-regression analysis showed that both 6MWT and HS were associated with 1-year mortality, HR6MWT 3.31 (95% CI 1.89–5.78, p<0.001) and HRHS2.39 (95% CI 1.33–4.27, p=0.003). The 0–3-month change in the 6MWT and the HS were associated with 1-year mortality, where patients who deteriorated had a poorer prognosis than those with improved fitness, HR6MWT 3.80 (95% CI 1.42–10.06, p=0.007) and HRHS 2.21 (95% CI 1.07–4.58, p=0.032).

    Conclusion: In frail elderly patients with a severe comorbidity burden, physical fitness in connection with emergency hospital care was independently associated with 1-year mortality. Moreover, a change in physical fitness during the first months after hospital care was important for the long-term prognosis. These results emphasize the importance of providing hospital care designed to prevent physical deterioration in frail elderly patients.

    Ort, förlag, år, upplaga, sidor
    Auckland, New Zealand: Dove Medical Press Ltd.(Dovepress), 2019
    Nyckelord
    frail elderly; mortality; physical fitness; six-minute walk test; handgrip strength test; in-hospital rehabilitation
    Nationell ämneskategori
    Geriatrik
    Identifikatorer
    urn:nbn:se:liu:diva-156220 (URN)10.2147/CIA.S198591 (DOI)000462319100001 ()30936688 (PubMedID)
    Anmärkning

    Funding Agencies|NU Hospital Group, Department of Research and Development

    Tillgänglig från: 2019-04-09 Skapad: 2019-04-09 Senast uppdaterad: 2020-04-07Bibliografiskt granskad
  • Gundmi Satish, Sajjan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanik och hållfasthetslära.
    Continuous Time Fatigue Modelling for Non-proportional Loading2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Fatigue analysis is a critical stage in the design of any structural component. Typically fatigue is analysed during post-processing, but as the size of the analysed component increases, the amount of data stored for the analysis increases simultaneously. This increases the computational and memory requirements of the system, intensifying the work load on the engineer. A continuum mechanics approach namely ’Continuous time fatigue model’, for fatigue analysis is available in a prior study which reduces the computational requirements by simultaneously computing fatigue along with the stress. This model implements a moving endurance surface in the stress space along with the damage evolution equation to compute high-cycle fatigue. In this thesis the continuous time fatigue model is compared with conventional model (ie.Cycle counting) to study its feasibility. The thesis also aims to investigate the continuous time fatigue model and an evolved version of the model is developed for non-proportional load cases to identify its limitations and benefits.

  • Disputation: 2020-05-15 09:30 K3, NorrköpingBeställ onlineKöp publikationen >>
    Svensson, Åsa
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Medie- och Informationsteknik. Linköpings universitet, Tekniska fakulteten.
    Human-automation teamwork: Current practices and future directions in air traffic control2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Denna avhandling utforskar teamwork mellan människa och automation inom flygtrafikledning. Flygtrafikledning är en högriskmiljö där komplex automation introduceras samtidigt som den mänskliga operatören har det juridiska ansvaret. Med ökade krav på produktivitet inom olika industrier (och även inom flygtrafikledning) så introduceras automation för effektiviteten, för att bibehålla säkerheten och för att hålla arbetsbelastningen för den mänskliga operatören inom acceptabla gränser. Tidigare forskning har däremot visat att automationen kan orsaka negativa effekter på den mänskliga operatören och på prestationen, som till exempel att tvinga ut operatören utanför kontrolloopen vilket leder till problem och förvirring. Tidigare forskning föreslår ett starkare samarbete mellan människa och automation där automationen är sedd som en teammedlem för att behålla operatören i loopen. För att uppnå ett sådant samarbete behöver automation vara människo-centrerad, att automation med andra ord är designad för operatörens underliggande behov.

    Syftet med denna avhandling är att utforska teamwork från olika vinklar inom flygtrafikledning för att förstå hur flygledare jobbar i nuvarande flygtrafikledningsmiljöer och för att förstå hur automation skulle kunna designas för att stödja teamwork mellan människa och automation. Studierna som denna avhandling bygger på har använt sig av intervjuer, simuleringar och enkäter, alla med operativa flygtrafikledare som deltagare.

    Resultatet tyder på att för både människa-människa teamwork och människa-automations teamwork så är teamwork faktorer så som flexibilitet och ömsesidig övervakning av teammedlemmarnas prestationer viktiga där övervakning av teammedlemmarnas prestationer är speciellt viktigt under stressiga situationer.

    När man designar automation bör man ta lärdom från teamwork mellan människor. Vidare så identifierar och behandlar arbetet inom denna avhandling två aspekter gällande teamwork mellan människa och automation: gränsmedvetenhet och implicit kommunikation. Dessa aspekter är föreslagna vi att stötta operatörens kunskap om automationen och kommunikationsflödet mellan operatören och automationen. Gränsmedvetenhet är operatörens kunskap om automationens förmågor, dess gränser och dess konsekvenser när automation går utanför dessa gränser. Implicit kommunikation är de outtalade eller implicita ledtrådar som operatören och automationen kan använda för att kommunicera med varandra. Det är föreslaget att implicit kommunikation kan baseras på arbetsmönster från operatören eller från prediktioner från automationen. Kunskapen från denna avhandling kan användas som ett underlagför vidare forskning och design av automation gällande operatörers kunskap om automationens gränser och kommunikationen inom teamet.

    Delarbeten
    1. Design implications for teamwork in ATC
    Öppna denna publikation i ny flik eller fönster >>Design implications for teamwork in ATC
    2019 (Engelska)Ingår i: Cognition, Technology & Work, ISSN 1435-5558, E-ISSN 1435-5566Artikel i tidskrift (Refereegranskat) Epub ahead of print
    Abstract [en]

    In air traffic control (ATC), teamwork is a key component among air traffic control operators (ATCOs) to safely direct theaircraft through the sky and on the ground. To be able to design for future ATC systems, we must understand how ATCOswork together, their teamwork, and how they experience and perceive teamwork, in different ATC environments. We conductedinterviews with 16 ATCOs working in four different ATC environments (en-route control, terminal area control, towercontrol for a small airport and tower control for a large airport in Sweden) and analysed the results in the light of the “BigFive” model of teamwork. The main contributions of this paper are to show: (1) how eight teamwork factors are differentlymanifested by the ATCOs in the different ATC environments, (2) that teamwork in ATC is important during routine operations,during stressful work, and during abnormal situations, and (3) that the design of the organisation, the environment,and the tools, affects teamwork and the importance of different teamwork factors.

    Ort, förlag, år, upplaga, sidor
    Springer London, 2019
    Nyckelord
    Air traffic control, Teamwork, Design, En-route, TMA, Air traffic control tower
    Nationell ämneskategori
    Övrig annan teknik
    Identifikatorer
    urn:nbn:se:liu:diva-160958 (URN)10.1007/s10111-019-00579-y (DOI)2-s2.0-85068791806 (Scopus ID)
    Tillgänglig från: 2019-10-16 Skapad: 2019-10-16 Senast uppdaterad: 2020-03-16Bibliografiskt granskad
    2. Analysis of work patterns as a foundation for human-automation communication in multiple remote towers
    Öppna denna publikation i ny flik eller fönster >>Analysis of work patterns as a foundation for human-automation communication in multiple remote towers
    2017 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    Implicit communication and higher levels of automation will be more important in the future multiple remote towers, in order to make the work of the Air Traffic Controller (ATCO) more efficient. However, the ATCO still needs to be in the control loop to make critical decisions. Human-automation collaboration requires teamwork, based on common ground and implicit communication. To design automation that supports teamwork and implicit communication, the automation must know how the ATCO is working. Sensors, like eye-tracking, and work patterns of the ATCO can give important information regarding the current situation in order for the automation to provide situation based support, through implicit communication to the ATCO. This paper addresses the current lack of teamwork and implicit communication between the ATCO and the automation in today’s air traffic control towers. Two case studies, using eye-tracking, were conducted. One study in a single tower simulator and one in a multiple remote tower simulator with three airports. The results show varying work patterns in three different stages of managing aircraft arrivals. This paper also discusses the potential for implicit communication and how work patterns are a foundation for designing air traffic control systems allowing teamwork.

    Nationell ämneskategori
    Människa-datorinteraktion (interaktionsdesign)
    Identifikatorer
    urn:nbn:se:liu:diva-164302 (URN)
    Konferens
    Twelfth USA/Europe Air Traffic Management Research and Development Seminar
    Tillgänglig från: 2020-03-16 Skapad: 2020-03-16 Senast uppdaterad: 2020-03-16
  • Disputation: 2020-04-29 09:00 Belladonna, Växthuset, LinköpingBeställ onlineKöp publikationen >>
    Frodlund, Martina
    Linköpings universitet, Institutionen för biomedicinska och kliniska vetenskaper, Avdelningen för inflammation och infektion. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Hjärt- och Medicincentrum, Reumatologiska kliniken i Östergötland.
    Antinuclear and antiphospholipid antibodies versus disease manifestations and clinical outcomes in systemic lupus erythematosus2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Systemic lupus erythematosus (SLE) has an exceptionally heterogeneous clinical spectrum, ranging from mild disease limited to skin and joints to severe manifestations with renal disorder, central nervous system disease, severe cytopenias and thromboembolic events. Important clinical challenges include the prediction of disease flares and the identification of individuals that are likely to evolve severe disease with accrual of organ damage and worse prognosis. Autoantibodies, i.e. antinuclear antibodies (ANA) and antiphospholipid antibodies (aPL), and interferon alpha (IFN-α) that contribute to formation of immune complexes with nuclear antigens, are hallmarks considered to drive the disease in a vicious circle of antigen exposure, autoantibody production, inflammation and organ damage. There are few good biomarkers to predict severe SLE and organ damage. The aim of this PhD project was thus to increase the knowledge regarding ANA as well as aPL, and other potential biomarkers in relation to clinical features and disease outcomes in SLE.

    As expected, we found that the homogeneous ANA staining pattern was most common, and that it was associated with the occurrence of the ‘immunological disorder’ criterion. Speckled ANA was the second most common staining pattern, and it was inversely associated with arthritis, the ‘immunological disorder’ criterion and organ damage (Paper I). We also demonstrated that a considerable proportion of the patients lost ANA-positivity over time, whereas consistent staining patterns were most frequent (Paper V).

    Survival of patients with SLE has improved. Yet, in comparison to the general population, irreversible organ damage and increased mortality remains a critical concern. In Paper II, our cross-sectional analysis showed that more than a quarter of the patients had any aPL isotype (IgG, IgM or IgA class), and 14% were classified with antiphospholipid antibody syndrome (APS). A positive lupus anticoagulant (LA) test and/or IgG aPL tests were associated with most APS-related events and organ damage. Lupus nephritis, tobacco smoking, LA-positivity and the use of statins and/or corticosteroids were strongly associated with damage accrual, while hydroxychloroquine seemed to be protective. IgA aPL was not uncommon (16%) in Swedish cases of SLE, and analysis of IgA aPL may add information among clinically suspected APS-patients testing negative for LA and other aPL isotypes.

    Despite modern management and tax-funded health care with universal access, almost two thirds of the patients accrued organ damage over time, and the main causes of death were identified as malignancy, infection, and cardiovascular disease. We could confirm well established risk factors for organ damage such as APS, hypertension, and/or the use of corticosteroids, but we also observed that other factors such as pericarditis, haemolytic anaemia, lymphopenia and myositis seems to be of importance in this view (Paper IV).

    We also demonstrated that levels of the extracellular matrix protein osteopontin (OPN) was correlated with disease activity in patients with recent-onset SLE. In addition, OPN levels reflected global organ damage and were associated with APS and could have potential as a valuable biomarker in SLE (Paper III).

    Additional studies are warranted to further establish the clinical and mechanistic relevance of ANA seroconversion, OPN, as well as the importance of IgA aPL. Vigilance for malignancies, a restricted use of corticosteroids and prevention of cardiovascular disease and APS events are among modifiable factors to prevent organ damage and premature mortality.

    This thesis emphasizes the importance of autoantibodies in the pathogenesis, and diagnosis, of SLE. The autoantibody profile can be of great importance for tailored therapy in order to minimize the risk of organ damage accrual, morbidity as well as mortality.

    Delarbeten
    1. Associations between antinuclear antibody staining patterns and clinical features of systemic lupus erythematosus: analysis of a regional Swedish register
    Öppna denna publikation i ny flik eller fönster >>Associations between antinuclear antibody staining patterns and clinical features of systemic lupus erythematosus: analysis of a regional Swedish register
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    2013 (Engelska)Ingår i: BMJ Open, ISSN 2044-6055, E-ISSN 2044-6055, Vol. 3, s. 1-8Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Objective Antinuclear antibody (ANA) analysis by immunofluorescence (IF) microscopy remains a diagnostic hallmark of systemic lupus erythematosus (SLE). The clinical relevance of ANA fine-specificities in SLE has been addressed repeatedly, whereas studies on IF-ANA staining patterns in relation to disease manifestations are very scarce. This study was performed to elucidate whether different staining patterns associate with distinct SLE phenotypes.

    Design Observational cohort study.

    Setting One university hospital rheumatology unit in Sweden.

    Participants The study population consisted of 222 cases (89% women; 93% Caucasians), where of 178 met ≥4/11 of the 1982 American College of Rheumatology (ACR-82) criteria. The remaining 20% had an SLE diagnosis based on positive IF-ANA (HEp-2 cells) and ≥2 typical organ manifestations at the time of diagnosis (Fries’ criteria).

    Outcome measures The IF-ANA staining patterns homogenous (H-ANA), speckled (S-ANA), combined homogenous and speckled (HS-ANA), centromeric (C-ANA), nucleolar (N-ANA)±other patterns and other nuclear patterns (oANA) were related to disease manifestations and laboratory measures. Antigen-specificities were also considered regarding double-stranded DNA (Crithidia luciliae) and the following extractable nuclear antigens: Ro/SSA, La/SSB, Smith antigen (Sm), small nuclear RNP (snRNP), Scl-70 and Jo-1 (immunodiffusion and/or line-blot technique).

    Results 54% of the patients with SLE displayed H-ANA, 22% S-ANA, 11% HS-ANA, 9% N-ANA, 1% C-ANA, 2% oANA and 1% were never IF-ANA positive. Staining patterns among patients meeting Fries’ criteria alone did not differ from those fulfilling ACR-82. H-ANA was significantly associated with the 10th criterion according to ACR-82 (‘immunological disorder’). S-ANA was inversely associated with arthritis, ‘immunological disorder’ and signs of organ damage.

    Conclusions H-ANA is the dominant IF-ANA pattern among Swedish patients with SLE, and was found to associate with ‘immunological disorder’ according to ACR-82. The second most common pattern, S-ANA, associated negatively with arthritis and organ damage.

    Nationell ämneskategori
    Reumatologi och inflammation
    Identifikatorer
    urn:nbn:se:liu:diva-91381 (URN)10.1136/bmjopen-2013-003608 (DOI)000326882800019 ()
    Konferens
    10th International Congress on SLE- Lupus 2013, 18-21 April 2013, Buenos Aires, Argentina
    Tillgänglig från: 2013-04-23 Skapad: 2013-04-23 Senast uppdaterad: 2020-04-07
    2. Immunoglobulin A anti-phospholipid antibodies in Swedish cases of systemic lupus erythematosus: associations with disease phenotypes, vascular events and damage accrual
    Öppna denna publikation i ny flik eller fönster >>Immunoglobulin A anti-phospholipid antibodies in Swedish cases of systemic lupus erythematosus: associations with disease phenotypes, vascular events and damage accrual
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    2018 (Engelska)Ingår i: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 194, nr 1, s. 27-38Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Immunoglobulin (Ig) G- and IgM-class anti-cardiolipin antibodies (aCL) and lupus anti-coagulant (LA) are included in the 1997 update of the American College of Rheumatology (ACR-97) systemic lupus erythematosus (SLE) criteria. Despite limited evidence, IgA-aCL and IgA anti-(2)-glycoprotein-I (anti-(2)GPI) were included in the 2012 Systemic Lupus International Collaborating Clinics criteria. The present study aimed to evaluate IgG-/IgA-/IgM-aCL and anti-(2)GPI occurrence in relation to disease phenotype, smoking habits, pharmacotherapy, anti-phospholipid syndrome (APS) and organ damage among 526 Swedish SLE patients meeting ACR-97. Patients with rheumatoid arthritis (n=100), primary Sjogrens syndrome (n=50) and blood donors (n=507) served as controls. Anti-phospholipid antibodies (aPL) were analysed by fluoroenzyme-immunoassays detecting aCL/anti-(2)GPI. Seventy-six (14%) SLE cases fulfilled the Sydney APS-criteria, and 1 aCL/anti-(2)GPI isotype (IgG/IgA/IgM) occurred in 138 SLE patients (26%). Forty-five (9%) of the SLE cases had IgA-aCL, 20 of whom (4%) lacked IgG-/IgM-aCL. Seventy-four (14%) tested positive for IgA anti-(2)GPI, 34 (6%) being seronegative regarding IgG/IgM anti-(2)GPI. Six (1%) had APS manifestations but were seropositive regarding IgA-aCL and/or IgA anti-(2)GPI in the absence of IgG/IgM-aPL and LA. Positive LA and IgG-aPL tests were associated with most APS-related events and organ damage. Exclusive IgA anti-(2)GPI occurrence associated inversely with Caucasian ethnicity [odds ratio (OR)=021, 95% confidence interval (CI)=006-072) and photosensitivity (OR=019, 95% CI=005-072). Nephritis, smoking, LA-positivity and statin/corticosteroid-medication associated strongly with organ damage, whereas hydroxychloroquine-medication was protective. In conclusion, IgA-aPL is not rare in SLE (16%) and IgA-aPL analysis may have additional value among SLE cases with suspected APS testing negative for other isotypes of aPL and LA.

    Ort, förlag, år, upplaga, sidor
    WILEY, 2018
    Nyckelord
    anti-phospholipid antibodies; anti-phospholipid syndrome; autoantibodies; immunoglobulin A; systemic lupus erythematosus
    Nationell ämneskategori
    Gastroenterologi
    Identifikatorer
    urn:nbn:se:liu:diva-151933 (URN)10.1111/cei.13180 (DOI)000445601500004 ()30208508 (PubMedID)
    Anmärkning

    Funding Agencies|Swedish Society for Medical Research; Swedish Rheumatism Association; Swedish Society of Medicine; King Gustaf Vs 80-year foundation; King Gustaf V and Queen Victorias Freemasons foundation; Swedish Heart-Lung Foundation; Swedish Research Council; County Council of Stockholm; County Council of Uppsala; County Council of Ostergotland

    Tillgänglig från: 2018-10-16 Skapad: 2018-10-16 Senast uppdaterad: 2020-04-07
    3. Osteopontin is associated with disease severity and antiphospholipid syndrome in well characterised Swedish cases of SLE
    Öppna denna publikation i ny flik eller fönster >>Osteopontin is associated with disease severity and antiphospholipid syndrome in well characterised Swedish cases of SLE
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    2017 (Engelska)Ingår i: Lupus Science and Medicine, ISSN 2053-8790, E-ISSN 1625-9823, Vol. 4, nr 1, s. 7artikel-id 000225Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Objective The variety of disease phenotypes among patients with SLE challenges the identification of new biomarkers reflecting disease activity and/or organ damage. Osteopontin (OPN) is an extracellular matrix protein with immunomodulating properties. Although raised levels have been reported, the pathogenic implications and clinical utility of OPN as a biomarker in SLE are far from clear. Thus, the aim of this study was to characterise OPN in SLE.

    Methods Sera from 240 well-characterised adult SLE cases classified according to the American College of Rheumatology (ACR) and/or the Systemic Lupus International Collaborating Clinics (SLICC) criteria, and 240 population-based controls were immunoassayed for OPN. The SLE Disease Activity Index 2000 (SLEDAI-2K) was used to evaluate disease activity and the SLICC/ACR Damage Index (SDI) to detect damage accrual.

    Results Serum OPN levels were in average raised fourfold in SLE cases compared with the controls (p<0.0001). OPN correlated with SLEDAI-2K, especially in patients with a disease duration of <12 months (r=0.666, p=0.028). OPN was highly associated with SDI (p<0.0001), especially in the renal (p<0.0001), cardiovascular (p<0.0001) and malignancy (p=0.012) domains. Finally, OPN associated with coherent antiphospholipid syndrome (APS; p=0.009), and both clinical and laboratory criteria of APS had significant positive impact on OPN levels.

    Conclusions In this cross-sectional study, circulating OPN correlates with disease activity in recent-onset SLE, reflects global organ damage and associates with APS. Longitudinal studies to dissect whether serum OPN also precedes and predicts future organ damage are most warranted.

    Ort, förlag, år, upplaga, sidor
    BMJ Publishing Group Ltd, 2017. s. 7
    Nationell ämneskategori
    Reumatologi och inflammation Neurologi Klinisk laboratoriemedicin Kardiologi Gastroenterologi
    Identifikatorer
    urn:nbn:se:liu:diva-140711 (URN)10.1136/lupus-2017-000225 (DOI)
    Tillgänglig från: 2017-09-08 Skapad: 2017-09-08 Senast uppdaterad: 2020-04-07Bibliografiskt granskad
    4. The majority of Swedish systemic lupus erythematosus patients are still affected by irreversible organ impairment: factors related to damage accrual in two regional cohorts
    Öppna denna publikation i ny flik eller fönster >>The majority of Swedish systemic lupus erythematosus patients are still affected by irreversible organ impairment: factors related to damage accrual in two regional cohorts
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    2019 (Engelska)Ingår i: Lupus, ISSN 0961-2033, E-ISSN 1477-0962, artikel-id UNSP 0961203319860198Artikel i tidskrift (Refereegranskat) Epub ahead of print
    Abstract [en]

    Background Although the survival of patients with systemic lupus erythematosus (SLE) has improved, irreversible organ damage remains a critical concern. We aimed to characterize damage accrual and its clinical associations and causes of death in Swedish patients. Methods Accumulation of damage was evaluated in 543 consecutively recruited and well-characterized cases during 1998-2017. The Systemic Lupus International Collaborating Clinics (SLICC)/American College of Rheumatology damage index (SDI) was used to estimate damage. Results Organ damage (SDI amp;gt;= 1) was observed in 59%, and extensive damage (SDI amp;gt;= 3) in 25% of cases. SDI amp;gt;= 1 was significantly associated with higher age at onset, SLE duration, the number of fulfilled SLICC criteria, neurologic disorder, antiphospholipid antibody syndrome (APS), hypertension, hyperlipidemia, depression and secondary Sjogrens syndrome (SS). In addition, SDI amp;gt;= 3 was associated with serositis, renal and haematological disorders and interstitial lung disease. A multiple regression model identified not only well-known risk factors like APS, antihypertensives and corticosteroids, but pericarditis, haemolytic anaemia, lymphopenia and myositis as being linked to SDI. Malignancy, infection and cardiovascular disease were the leading causes of death. Conclusions After a mean SLE duration of 17 years, the majority of todays Swedish SLE patients have accrued damage. We confirm previous observations and report some novel findings regarding disease phenotypes and damage accrual.

    Ort, förlag, år, upplaga, sidor
    SAGE PUBLICATIONS LTD, 2019
    Nyckelord
    Damage accrual; immunosuppressants; mortality; SLE phenotypes; Sweden; systemic lupus erythematosus
    Nationell ämneskategori
    Reumatologi och inflammation
    Identifikatorer
    urn:nbn:se:liu:diva-159259 (URN)10.1177/0961203319860198 (DOI)000477186800001 ()31296137 (PubMedID)
    Anmärkning

    Funding Agencies|Swedish Rheumatism Association; County Council of Ostergotland; Swedish Society of Medicine; King Gustaf Vs 80-year Anniversary foundation; King Gustaf V and Queen Victorias Freemasons foundation; Ingegerd Johansson donation; Selander foundation; County Council of Uppsala

    Tillgänglig från: 2019-08-06 Skapad: 2019-08-06 Senast uppdaterad: 2020-04-07
    5. Longitudinal anti-nuclear antibody (ANA) seroconversion in systemic lupus erythematosus: a prospective study of Swedish cases with recent-onset disease
    Öppna denna publikation i ny flik eller fönster >>Longitudinal anti-nuclear antibody (ANA) seroconversion in systemic lupus erythematosus: a prospective study of Swedish cases with recent-onset disease
    Visa övriga...
    2020 (Engelska)Ingår i: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 199, nr 3, s. 245-254Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Serum immunoglobulin (Ig)G anti-nuclear antibodies (ANA) detected by indirect immunofluorescence (IF) microscopy remains a hallmark of systemic lupus erythematosus (SLE). Whether or not IF-ANA status varies over time is controversial. We therefore designed a prospective study with longitudinal follow-up of patients with recent-onset SLE. The study population consisted of 54 recently diagnosed SLE cases, all meeting the 1982 American College of Rheumatology (ACR) and/or the 2012 Systemic Lupus International Collaborating Clinics (SLICC) criteria. Clinical follow-up data, including disease activity, organ damage and sera, were collected from clinical onset of SLE and onwards, in most cases yearly (0-96 months). IF-ANA was analysed on human epithelial cells-2 (HEp-2) cells and categorized regarding staining patterns. Using an addressable laser bead assay (FIDIS (TM) Connective profile), we measured IgG-ANA fine specificities against Ro52/SSA, Ro60/SSA, Sjogrens syndrome type B antigen (La/SSB), Smith antigen (Sm), Smith antigen/ribonucleoprotein (Sm/RNP), U1 RNP (U1RNP), dsDNA, ribosomal-P protein and histone. At baseline, all patients were judged ANA-positive at an abnormal titre corresponding to the 95th percentile of healthy blood donors, but seven of 54 patients (13%) lost ANA-positivity over time. Homogeneous (AC-1; 46%) and speckled (AC-4 or 5; 31%) were the most frequently observed patterns at inclusion, whereas 7% switched pattern at least once during follow-up. Established associations between ANA fine specificities and clinical data were confirmed. Levels of anti-Sm/RNP, but not of anti-dsDNA, correlated with clinical disease activity [modified SLE disease activity 2000 (mSLEDAI-2K)]. Our data indicate that a considerable proportion of Swedish patients with SLE lose ANA-positivity over time, whereas consistent staining patterns were frequent. The clinical and mechanistic relevance of ANA seroconversion remains uncertain. Further prospective evaluations in larger SLE populations with more diverse ethnicities are warranted.

    Ort, förlag, år, upplaga, sidor
    Wiley-Blackwell Publishing Inc., 2020
    Nyckelord
    autoantibodies; autoimmunity; complement; human; systemic lupus erythematosus
    Nationell ämneskategori
    Gastroenterologi
    Identifikatorer
    urn:nbn:se:liu:diva-164196 (URN)10.1111/cei.13402 (DOI)000513952100007 ()31778219 (PubMedID)2-s2.0-85076720021 (Scopus ID)
    Anmärkning

    Funding Agencies|the Swedish Society of Medicine; Swedish Society of Medicine; the County Council of Ostergotland; Swedish Rheumatism Association; the Swedish Rheumatism Association; the King Gustaf V and Queen Victorias Freemasons foundation; the King Gustaf Vs 80-year Anniversary foundation

    Tillgänglig från: 2020-03-11 Skapad: 2020-03-11 Senast uppdaterad: 2020-04-07Bibliografiskt granskad
  • Areström, Elin
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Affärsrätt. Linköpings universitet, Filosofiska fakulteten.
    Mervärdesskatt och balanserade termiska nät2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I takt med att nya samhällsföreteelser utvecklas uppkommer samtidigt frågor om hur dessa relaterar till gällande rätt. Fokus i denna uppsats är att utreda i vilka fall så kallade affärer inom den nya tekniska samhällsföreteelsen balanserade termiska nät (BTN) är skattepliktiga för mervärdesskatt,vilka undantag som finns samt övriga mervärdesskatterättsliga svårigheter som BTN kan tänkas aktualisera.

    Tekniken i BTN bygger på att termisk energi balanseras mellan byggnader, genom vatten, utefter deras momentana behov. Dessa affärer, som energiutbytena utgör, kan ske mellan såväl företag som privatpersoner. Vilken part som agerar köpare respektive säljare kan således skifta över tidbaserat på byggnadernas värmeprofiler. Denna uppsats har emellertid avgränsats till att behandla frågan om etablerade BTN med ett begränsat antal parter vilka själva äger näten.

    Utifrån analyskapitlet dras slutsatsen att svaret om mervärdesskatteplikt råder eller ej inte är givet för alla affärer inom ett etablerat BTN. Emellertid kan det sägas att det generellt sett råder skatteplikt för mervärdesskatt för affärerna, förutsatt att ersättning utges, antingen i form av pengar eller genom byten av energi. Likväl återfinns undantag för bland annat de fall där omsättning understiger 30 000 kronor under beskattningsåret och två år innan enligt 9d kap. 1 § ML. Undantag råder även för situationer där ersättning inte utges på grund av att energin ges bort. Emellertid leder detta faktum till att avdragsrätt även råder i alla scenarion i vilka skatteplikt för mervärdesskatt råder, utom i fall där det är privatpersoner som köpt energi för att nyttja i en stadigvarande bostad enligt 8 kap. 9 § 1 st. 1 p. ML. Syftet med mervärdesskatten är att träffa all konsumtion och att affärer i ett BTN då, generellt sett, inte skulle vara skattepliktiga strider mot det syftet, vilket ger att slutsatsen är rimlig. Det hade även stridit mot neutralitetsprincipen samt syftet att motverka påverkan på konkurrensen, ifall mervärdesskatt inte hade utgått på affärer inom ett BTN, eftersom det gör det på andra former av energiförsörjning.

    Flertalet andra mervärdesskatterättsliga frågor uppstår även relaterat till etablerade BTN. En stor del av dessa och dess problematik, vilket lyfts i uppsatsen, ligger emellertid i det faktum att samtliga parter kan agera både köpare och säljare och därmed intar positioner de inte tidigare haft. Lagstiftningen idag är nämligen inte optimalt utformad för att slutkonsumenter själva även ska sälja det som konsumeras på ett sådant sätt som sker inom ett BTN. Således är det önskvärt meden viss översyn av mervärdesskattelagstiftningen så att förutsebarheten för situationer likt BTN ökar.

  • Bertilsson, Mattias
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Affärsrätt. Linköpings universitet, Filosofiska fakulteten.
    Återtagandeförbehåll: Och möjligheten till ett eventuellt införande av ett sakrättsligt moment2020Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Återtagandeförbehåll är en säkerhetsrätt som ger en säljare rätt att återta såld vara från en köpare om förutsättningarna för förbehållet är uppfyllda. Upplägget förhandlas fram mellan köpare och säljare och gäller således dem emellan. Det kan dock i vissa fall även bli gällande mot tredje man. För att en säljare ska kunna skydda sin rättighet att återta såld vara mot tredje man behöver säljaren ett sakrättsligt skydd, vilket ger säljaren en bättre rätt till den sålda varan än tredje man. Som exempel är det sakrättsliga skyddet aktuellt ifall köparen försätts i konkurs innan köpeskillingen har betalats till fullo, eller om köparen säljer vidare varan utan att tillfråga säljaren. Konflikter mellan avtalspart och tredje man är sakrättens kännetecken och enligt huvudregeln erhålls ett sakrättsligt skydd i samband med ett sakrättsligt moment. Ett sådant moment saknas dock när det gäller återtagandeförbehåll. Säljarens bättre rätt har blivit prövad flera gånger i domstol och rättspraxis har vuxit fram där det går att utläsa vilka förutsättningar som krävs för att ett återtagandeförbehåll ska medföra ett sakrättsligt skydd för säljaren.

    Fokus i uppsatsen ligger på att diskutera möjligheten att införa ett register över återtagandeförbehåll såsom sakrättsligt moment, samt de för- och nackdelar ett sådant införande skulle medbringa. För att kunna föra en diskussion om ett eventuellt återtagandeförbehållsregister är det nödvändigt att gå igenom grundläggande sakrättsliga principer samt förklara gällande rätt vad gäller återtagandeförbehåll.

    Ett eventuellt register för återtagandeförbehåll skulle medföra vissa fördelaktiga samhällsekonomiska effekter. Bland annat skulle utrymmet för osäkerhet och orättvisor mellan de säkerhetsrätter med sakrättsligt moment och de utan, bli mindre. Kreditrisken för säljaren skulle minska ifall återtagandeförbehåll gav ett starkare skydd än idag, vilket skulle främja kredithandeln i och med att risken är en av de bidragande faktorerna vid prissättning. Om ansvaret för registret tillfaller den privata sektorn skulle registrering av ett återtagandeförbehåll kunna vara kopplat till kreditundersökningar och andra tjänster som tillsammans skulle skapa synergieffekter. Kostnaderna kopplade till utvecklingen och underhållet av ett eventuellt register kan hållas nere med hjälp av nyttjandet av blockkedjeteknik och redan existerande registersystem. Det finns dock alternativ till återtagandeförbehåll som framstår som bättre, vilket skulle tala mot ett införande av ett återtagandeförbehållsregister.

  • Clark, Andrew
    et al.
    School of Health and Society, University of Salford, Salford, Greater Manchester, UK.
    Campbell, Sarah
    School of Nursing, Midwifery and Social Work, University of Manchester, Manchester, UK.
    Keady, John
    School of Nursing, Midwifery and Social Work, University of Manchester, Manchester, UK.
    Kullberg, Agneta
    Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för samhälle och hälsa.
    Manji, Kainde
    Rummery, Kirstein
    Faculty of Social Science, University of Stirling, Colin Bell Building, Stirling, UK.
    Ward, Richard
    Faculty of Social Science, University of Stirling, Colin Bell Building, Stirling, UK.
    Neighbourhoods as relational places for people living with dementia2020Ingår i: Social Science and Medicine, ISSN 0277-9536, E-ISSN 1873-5347, Vol. 252Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An increase in the number of people living independently with dementia across the developed world has focused attention on the relevance of neighbourhood spaces for enabling or facilitating good social health and wellbeing. Taking the lived experiences and daily realities of people living with dementia as a starting point, this paper contributes new understanding about the relevance of local places for supporting those living with the condition. The paper outlines findings from a study of the neighbourhood experiences, drawing on new data collected from a creative blend of qualitatively-driven mixed methods with people living in a diverse array of settings across three international settings. The paper details some of the implications of neighbourhoods as sites of social connection based on material from 67 people living with dementia and 62 nominated care-partners. It demonstrates how neighbourhoods are experienced as relational places and considers how people living with dementia contribute to the production of such places through engagement and interaction, and in ways that may be beneficial to social health. We contend that research has rarely focused on the subjective, experiential and ‘everyday’ social practices that contextualise neighbourhood life for people living with dementia. In doing so, the paper extends empirical and conceptual understanding of the relevance of neighbourhoods as relational sites of connection, interaction, and social engagement for people living with dementia.

  • Disputation: 2020-04-29 13:15 Ada Lovelace, hus B, LinköpingBeställ onlineKöp publikationen >>
    Andersson, Olov
    Linköpings universitet, Institutionen för datavetenskap, Artificiell intelligens och integrerade datorsystem. Linköpings universitet, Tekniska fakulteten.
    Learning to Make Safe Real-Time Decisions Under Uncertainty for Autonomous Robots2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Robots are increasingly expected to go beyond controlled environments in laboratories and factories, to act autonomously in real-world workplaces and public spaces. Autonomous robots navigating the real world have to contend with a great deal of uncertainty, which poses additional challenges. Uncertainty in the real world accrues from several sources. Some of it may originate from imperfect internal models of reality. Other uncertainty is inherent, a direct side effect of partial observability induced by sensor limitations and occlusions. Regardless of the source, the resulting decision problem is unfortunately computationally intractable under uncertainty. This poses a great challenge as the real world is also dynamic. It  will not pause while the robot computes a solution. Autonomous robots navigating among people, for example in traffic, need to be able to make split-second decisions. Uncertainty is therefore often neglected in practice, with potentially catastrophic consequences when something unexpected happens. The aim of this thesis is to leverage recent advances in machine learning to compute safe real-time approximations to decision-making under uncertainty for real-world robots. We explore a range of methods, from probabilistic to deep learning, as well as different combinations with optimization-based methods from robotics, planning and control. Driven by applications in robot navigation, and grounded in experiments with real autonomous quadcopters, we address several parts of this problem. From reducing uncertainty by learning better models, to directly approximating the decision problem itself, all the while attempting to satisfy both the safety and real-time requirements of real-world autonomy.

    Delarbeten
    1. Model-Predictive Control with Stochastic Collision Avoidance using Bayesian Policy Optimization
    Öppna denna publikation i ny flik eller fönster >>Model-Predictive Control with Stochastic Collision Avoidance using Bayesian Policy Optimization
    2016 (Engelska)Ingår i: IEEE International Conference on Robotics and Automation (ICRA), 2016, Institute of Electrical and Electronics Engineers (IEEE), 2016, s. 4597-4604Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    Robots are increasingly expected to move out of the controlled environment of research labs and into populated streets and workplaces. Collision avoidance in such cluttered and dynamic environments is of increasing importance as robots gain more autonomy. However, efficient avoidance is fundamentally difficult since computing safe trajectories may require considering both dynamics and uncertainty. While heuristics are often used in practice, we take a holistic stochastic trajectory optimization perspective that merges both collision avoidance and control. We examine dynamic obstacles moving without prior coordination, like pedestrians or vehicles. We find that common stochastic simplifications lead to poor approximations when obstacle behavior is difficult to predict. We instead compute efficient approximations by drawing upon techniques from machine learning. We propose to combine policy search with model-predictive control. This allows us to use recent fast constrained model-predictive control solvers, while gaining the stochastic properties of policy-based methods. We exploit recent advances in Bayesian optimization to efficiently solve the resulting probabilistically-constrained policy optimization problems. Finally, we present a real-time implementation of an obstacle avoiding controller for a quadcopter. We demonstrate the results in simulation as well as with real flight experiments.

    Ort, förlag, år, upplaga, sidor
    Institute of Electrical and Electronics Engineers (IEEE), 2016
    Serie
    Proceedings of IEEE International Conference on Robotics and Automation, ISSN 1050-4729
    Nyckelord
    Robot Learning, Collision Avoidance, Robotics, Bayesian Optimization, Model Predictive Control
    Nationell ämneskategori
    Robotteknik och automation Datavetenskap (datalogi)
    Identifikatorer
    urn:nbn:se:liu:diva-126769 (URN)10.1109/ICRA.2016.7487661 (DOI)000389516203138 ()
    Konferens
    IEEE International Conference on Robotics and Automation (ICRA), 2016, Stockholm, May 16-21
    Projekt
    CADICSELLIITNFFP6CUASSHERPA
    Forskningsfinansiär
    Linnaeus research environment CADICSELLIIT - The Linköping‐Lund Initiative on IT and Mobile CommunicationsEU, FP7, Sjunde ramprogrammetStiftelsen för strategisk forskning (SSF)
    Tillgänglig från: 2016-04-04 Skapad: 2016-04-04 Senast uppdaterad: 2020-03-26Bibliografiskt granskad
    2. Receding-Horizon Lattice-based Motion Planning with Dynamic Obstacle Avoidance
    Öppna denna publikation i ny flik eller fönster >>Receding-Horizon Lattice-based Motion Planning with Dynamic Obstacle Avoidance
    Visa övriga...
    2018 (Engelska)Ingår i: 2018 IEEE Conference on Decision and Control (CDC), Institute of Electrical and Electronics Engineers (IEEE), 2018, s. 4467-4474Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    A key requirement of autonomous vehicles is the capability to safely navigate in their environment. However, outside of controlled environments, safe navigation is a very difficult problem. In particular, the real-world often contains both complex 3D structure, and dynamic obstacles such as people or other vehicles. Dynamic obstacles are particularly challenging, as a principled solution requires planning trajectories with regard to both vehicle dynamics, and the motion of the obstacles. Additionally, the real-time requirements imposed by obstacle motion, coupled with real-world computational limitations, make classical optimality and completeness guarantees difficult to satisfy. We present a unified optimization-based motion planning and control solution, that can navigate in the presence of both static and dynamic obstacles. By combining optimal and receding-horizon control, with temporal multi-resolution lattices, we can precompute optimal motion primitives, and allow real-time planning of physically-feasible trajectories in complex environments with dynamic obstacles. We demonstrate the framework by solving difficult indoor 3D quadcopter navigation scenarios, where it is necessary to plan in time. Including waiting on, and taking detours around, the motions of other people and quadcopters.

    Ort, förlag, år, upplaga, sidor
    Institute of Electrical and Electronics Engineers (IEEE), 2018
    Serie
    Conference on Decision and Control (CDC), ISSN 2576-2370 ; 2018
    Nyckelord
    Motion Planning, Optimal Control, Autonomous System, UAV, Dynamic Obstacle Avoidance, Robotics
    Nationell ämneskategori
    Reglerteknik
    Identifikatorer
    urn:nbn:se:liu:diva-152131 (URN)10.1109/CDC.2018.8618964 (DOI)9781538613955 (ISBN)9781538613948 (ISBN)9781538613962 (ISBN)
    Konferens
    2018 IEEE 57th Annual Conference on Decision and Control (CDC),17-19 December, Miami, Florida, USA
    Forskningsfinansiär
    VINNOVAKnut och Alice Wallenbergs StiftelseStiftelsen för strategisk forskning (SSF)ELLIIT - The Linköping‐Lund Initiative on IT and Mobile CommunicationsVetenskapsrådetLinnaeus research environment CADICSCUGS (National Graduate School in Computer Science)
    Anmärkning

    This work was partially supported by FFI/VINNOVA, the Wallenberg Artificial Intelligence, Autonomous Systems and Software Program (WASP) funded by Knut and Alice Wallenberg Foundation, the Swedish Foundation for Strategic Research (SSF) project Symbicloud, the ELLIIT Excellence Center at Linköping-Lund for Information Technology, Swedish Research Council (VR) Linnaeus Center CADICS, and the National Graduate School in Computer Science, Sweden (CUGS).

    Tillgänglig från: 2018-10-18 Skapad: 2018-10-18 Senast uppdaterad: 2020-03-26Bibliografiskt granskad
    3. Deep Learning Quadcopter Control via Risk-Aware Active Learning
    Öppna denna publikation i ny flik eller fönster >>Deep Learning Quadcopter Control via Risk-Aware Active Learning
    2017 (Engelska)Ingår i: Proceedings of The Thirty-first AAAI Conference on Artificial Intelligence (AAAI) / [ed] Satinder Singh and Shaul Markovitch, AAAI Press, 2017, Vol. 5, s. 3812-3818Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    Modern optimization-based approaches to control increasingly allow automatic generation of complex behavior from only a model and an objective. Recent years has seen growing interest in fast solvers to also allow real-time operation on robots, but the computational cost of such trajectory optimization remains prohibitive for many applications. In this paper we examine a novel deep neural network approximation and validate it on a safe navigation problem with a real nano-quadcopter. As the risk of costly failures is a major concern with real robots, we propose a risk-aware resampling technique. Contrary to prior work this active learning approach is easy to use with existing solvers for trajectory optimization, as well as deep learning. We demonstrate the efficacy of the approach on a difficult collision avoidance problem with non-cooperative moving obstacles. Our findings indicate that the resulting neural network approximations are least 50 times faster than the trajectory optimizer while still satisfying the safety requirements. We demonstrate the potential of the approach by implementing a synthesized deep neural network policy on the nano-quadcopter microcontroller.

    Ort, förlag, år, upplaga, sidor
    AAAI Press, 2017
    Serie
    Proceedings of the AAAI Conference on Artificial Intelligence, ISSN 2159-5399, E-ISSN 2374-3468 ; 5
    Nationell ämneskategori
    Datorseende och robotik (autonoma system) Datavetenskap (datalogi)
    Identifikatorer
    urn:nbn:se:liu:diva-132800 (URN)978-1-57735-784-1 (ISBN)
    Konferens
    Thirty-First AAAI Conference on Artificial Intelligence (AAAI), 2017, San Francisco, February 4–9.
    Projekt
    ELLIITCADICSNFFP6SYMBICLOUDCUGS
    Forskningsfinansiär
    Linnaeus research environment CADICSELLIIT - The Linköping‐Lund Initiative on IT and Mobile CommunicationsEU, FP7, Sjunde ramprogrammetCUGS (National Graduate School in Computer Science)Stiftelsen för strategisk forskning (SSF)
    Tillgänglig från: 2016-11-25 Skapad: 2016-11-25 Senast uppdaterad: 2020-03-26Bibliografiskt granskad
    4. Deep RL for Autonomous Robots: Limitations and Safety Challenges
    Öppna denna publikation i ny flik eller fönster >>Deep RL for Autonomous Robots: Limitations and Safety Challenges
    2019 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    With the rise of deep reinforcement learning, there has also been a string of successes on continuous control problems using physics simulators. This has lead to some optimism regarding use in autonomous robots and vehicles. However, to successful apply such techniques to the real world requires a firm grasp of their limitations. As recent work has raised questions of how diverse these simulation benchmarks really are, we here instead analyze a popular deep RL approach on toy examples from robot obstacle avoidance. We find that these converge very slowly, if at all, to safe policies. We identify convergence issues on stochastic environments and local minima as problems that warrant more attention for safety-critical control applications.

    Nationell ämneskategori
    Datavetenskap (datalogi)
    Identifikatorer
    urn:nbn:se:liu:diva-164581 (URN)
    Konferens
    European Symposium on Artificial Neural Networks, Computational Intelligence and Machine Learning
    Forskningsfinansiär
    Wallenberg AI, Autonomous Systems and Software Program (WASP)Stiftelsen för strategisk forskning (SSF)ELLIIT - The Linköping‐Lund Initiative on IT and Mobile Communications
    Tillgänglig från: 2020-03-26 Skapad: 2020-03-26 Senast uppdaterad: 2020-04-06
    5. Model-Based Reinforcement Learning in Continuous Environments Using Real-Time Constrained Optimization
    Öppna denna publikation i ny flik eller fönster >>Model-Based Reinforcement Learning in Continuous Environments Using Real-Time Constrained Optimization
    2015 (Engelska)Ingår i: Proceedings of the Twenty-Ninth AAAI Conference on Artificial Intelligence (AAAI) / [ed] Blai Bonet and Sven Koenig, AAAI Press, 2015, s. 2497-2503Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    Reinforcement learning for robot control tasks in continuous environments is a challenging problem due to the dimensionality of the state and action spaces, time and resource costs for learning with a real robot as well as constraints imposed for its safe operation. In this paper we propose a model-based reinforcement learning approach for continuous environments with constraints. The approach combines model-based reinforcement learning with recent advances in approximate optimal control. This results in a bounded-rationality agent that makes decisions in real-time by efficiently solving a sequence of constrained optimization problems on learned sparse Gaussian process models. Such a combination has several advantages. No high-dimensional policy needs to be computed or stored while the learning problem often reduces to a set of lower-dimensional models of the dynamics. In addition, hard constraints can easily be included and objectives can also be changed in real-time to allow for multiple or dynamic tasks. The efficacy of the approach is demonstrated on both an extended cart pole domain and a challenging quadcopter navigation task using real data.

    Ort, förlag, år, upplaga, sidor
    AAAI Press, 2015
    Nyckelord
    Reinforcement Learning, Gaussian Processes, Optimization, Robotics
    Nationell ämneskategori
    Datavetenskap (datalogi) Datorseende och robotik (autonoma system)
    Identifikatorer
    urn:nbn:se:liu:diva-113385 (URN)978-1-57735-698-1 (ISBN)
    Konferens
    Twenty-Ninth AAAI Conference on Artificial Intelligence (AAAI), January 25-30, 2015, Austin, Texas, USA.
    Forskningsfinansiär
    Linnaeus research environment CADICSeLLIIT - The Linköping‐Lund Initiative on IT and Mobile CommunicationsStiftelsen för strategisk forskning (SSF)VINNOVAEU, FP7, Sjunde ramprogrammet
    Tillgänglig från: 2015-01-16 Skapad: 2015-01-16 Senast uppdaterad: 2020-03-26Bibliografiskt granskad
    6. Real-Time Robotic Search using Structural Spatial Point Processes
    Öppna denna publikation i ny flik eller fönster >>Real-Time Robotic Search using Structural Spatial Point Processes
    Visa övriga...
    2019 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Nationell ämneskategori
    Data- och informationsvetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-159698 (URN)
    Konferens
    Proceedings of the 35th Conference on Uncertainty in Artificial Intelligence (UAI 2019), Tel Aviv, Israel, July 22-25, 2019
    Tillgänglig från: 2019-08-19 Skapad: 2019-08-19 Senast uppdaterad: 2020-03-26Bibliografiskt granskad
  • Thorling, Åsa
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Pedagogik och didaktik. Linköpings universitet, Utbildningsvetenskap.
    Inkludering i Singapore: Svenska föräldrar till barn i behov av särskilt stöd beskriver sina skolerfarenheter2020Självständigt arbete på avancerad nivå (masterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Syftet med studien är att bidra med kunskap och erfarenheter från sex utlandssvenska föräldrar om skolgång för svenska barn, som har behov av specialpedagogiska insatser för att finna social samvaro och utvecklas akademiskt, i en utländsk kontext. Studien har en kvalitativ praxisnära förståelsegrund och ger perspektiv på det omtvistade begreppet inkludering och vad det kan innebära för individer i en vinstdriven skolmarknad i Singapore. Denna berättelseinspirerade intervjustudie har sin utgångspunkt i sociokulturell systemteori med ett utvecklingsekologiskt perspektiv som betonar människors utveckling i samspel med sin miljö. Med Bronfenbrenners ekologiska utvecklingsmodell som referensram synliggörs en kulturellt grundad obalans i specialpedagogiska perspektivmöten samt kontrasterande eller kompletterande perspektiv på specialpedagogiska behov med olika följder som föräldrarna måste förhålla sig till.

     

    Resultatet visar att föräldrarna i studien önskar ökad transparens, minskad ovisshet och större tydlighet om förutsättningarna för funktionell och upplevd inkluderingskvalitet i en aktiv skolvalsprocess för deras barns skull. Inkluderingsbegreppet i Singapore är i dagsläget långt ifrån likställt med ett likvärdighetsperspektiv eller idén om att skolor skulle ha ett kompensatoriskt uppdrag. Studien påvisar att genom stora kunskaper om det egna barnets specialpedagogiska behov, noggranna förberedelser inför en flytt, aktiv delaktighet i skolgången samt ekonomiska resurser ökas graden av inkluderingsupplevelse för en långsiktigt positiv identitetsutveckling. Vidare visas att finna skolor med inkluderande förhållningssätt och gedigna kunskaper om specialpedagogiska behov underlättas av ett stödjande nätverk, driftiga förmågor och mycket tid för att förstå underliggande specialpedagogiska värderingar och förutsättningar på flera nivåer inom den utvecklingsekologiska modellen. Med tid och erfarenhet ökar kvaliteten på samverkan och en holistisk samsyn runt barnet. Detta sker framför allt på skolor med lång historia, väl inarbetade mångfaldsperspektiv och en inkluderande skolgemenskap för både barn och föräldrar. 

    Sökord: inkludering, utlandssvenska barn, föräldraperspektiv, specialpedagogiska behov

  • Disputation: 2020-04-28 09:15 Seminariet är öppet för allmänheten via Zoom or Team (Kontakta tomohiko.sakao@liu.se för att få länken.), LinköpingBeställ onlineKöp publikationen >>
    Neramballi, Abhijna
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell miljöteknik. Linköpings universitet, Tekniska fakulteten.
    Understanding and Supporting Product-Service System Designing: Preliminary Insights and Support for Designing Resource-Efficient and Effective Solutions2020Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    This licentiate thesis aims to establish the basis for scientifically understanding and supporting the cognitive processes involved in the conceptual design of resource- efficient and effective product-service systems (PSSs). The research carried out is transdisciplinary in nature and includes both prescriptive and descriptive studies.

    First, the cognitive nature of conceptual PSS designing is investigated. Multiple pre-experimental protocol studies in a laboratory setting are carried out to do so. The cohort of these explorative studies includes experienced industrial practitioners conceptually designing a resource-efficient PSS. These descriptive studies provide quantitative insights into the cognitive effort expended by designers on various design issues and processes during conceptual PSS designing and its potential differences to conceptual product designing. These insights form the basis for future research that can eventually shine light on this complex process with statistically significant empirical results.

    Second, the essence of extant prescriptive PSS design principles, methods and tools is distilled through a literature analysis and synthesis of the state of the art. Subsequently, important aspects that need to be considered during conceptual PSS designing are consolidated in the form of a PSS design schema.

    Third, a design navigator named lifecycle-oriented function deployment (LFD) is developed. LFD is essentially a contextual decision-making support tool, developed to guide the conceptual designing of environmentally benign PSSs. This tool informs the designers regarding the potential environmental impacts of specific design parameters of an existing offering. It subsequently guides the designers in the redesign of this existing offering into a PSS with relatively benign environmental impacts.

    Fourth, the effects of the two proposed prescriptions are tested empirically. True experimental protocol studies are carried out in a laboratory setting to test the effects of the prescriptive PSS design schema on the cognition of PSS designers. LFD is applied in an industrial case study using the action design research method, to support the conceptual redesign of an existing product-centric offering into an environmentally benign PSS. Environmental impacts of the PSS concepts generated using LFD are then evaluated in comparison to that of the existing offering, using simulated lifecycle assessment. A semi-structured interview is carried out to evaluate the utility and usability of LFD, with the company personnel involved in the conceptual redesign process.

    This licentiate thesis is an effort to effectively design the future research work of the author. This future work will aim to support and establish generalizable scientific knowledge regarding the conceptual designing of resource-efficient and effective PSSs.

    Delarbeten
    1. What Do Experienced Practitioners Discuss When Designing Product/Service Systems?
    Öppna denna publikation i ny flik eller fönster >>What Do Experienced Practitioners Discuss When Designing Product/Service Systems?
    2019 (Engelska)Ingår i: DCC 2018: Design Computing and Cognition '18 / [ed] John S. Gero, Springer, 2019, s. 361-380Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    This paper presents empirical results aimed at increasing the understanding of conceptual activities of Product/Service Systems (PSS) design by experienced designers from industry. Results are derived from a protocol analysis of five PSS design sessions, using the Function–Behavior–Structure coding scheme. Sessions included five pairs of professional designers and the task was to redesign a concept for an existing PSS to improve its resource efficiency. The results show (i) the distribution of design issues during PSS design sessions, (ii) on average 47% of the overall cognitive design effort spent by the designers is related to behavior, and (iii) all the design issues except requirements are constantly focused on during the entirety of the design sessions. Major differences compared to product design are the average occurrence of function for PSS design (23%) for product design (4%) and of structure for PSS design (22%) compared to the product design (35%).

    Ort, förlag, år, upplaga, sidor
    Springer, 2019
    Nyckelord
    Product-Service Systems Design, Design Cognition, Design Science, Function-Behavior-Structure Ontology, Protocol Analysis, Resource efficiency
    Nationell ämneskategori
    Interaktionsteknik
    Identifikatorer
    urn:nbn:se:liu:diva-153834 (URN)10.1007/978-3-030-05363-5_20 (DOI)978-3-030-05363-5 (ISBN)978-3-030-05362-8 (ISBN)
    Konferens
    International Conference on Design Computing and Cognition, DCC 2018, Politecnico di Milano, Lecco Campus on Lake Como (near Milan), Italy, 2–4 July 2018
    Projekt
    Mistra REES (Resource Efficient and Effective Solutions) (grant number DIA 2014/16)a grant from the US National Science Foundation Grant No. CMMI‐1400466
    Tillgänglig från: 2019-01-12 Skapad: 2019-01-12 Senast uppdaterad: 2020-04-06Bibliografiskt granskad
    2. Effects of a design support on practitioners designing a Product/Service System - a case study
    Öppna denna publikation i ny flik eller fönster >>Effects of a design support on practitioners designing a Product/Service System - a case study
    2019 (Engelska)Ingår i: Human Behaviour in Design: Proceedings of the 2nd SIG conference, April 2019 / [ed] Yvonne Eriksson and Kristin Paetzold, Neubiberg: Institut für Technische Produktentwicklung, Universität der Bundeswehr München , 2019, s. 11-22Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    This paper presents empirical evidence on which to ground the understanding of effects of a design support on Product/Service Systems (PSS) designing. The effects are measured by the extent of application of a systems perspective and level of integration of product and service elements during PSS designing. Protocol analyses of a control team and an experiment team, involving experienced practitioners performing an identical PSS design task are conducted. Only the experiment team is provided with the design support. The Function–Behavior–Structure ontology and a scheme for the systems perspective are utilized to code the data. Results show preliminary insight into the influence of a design support. The focus on systems level abstraction shows a three-fold increase, the cognitive effort spent on behavior of structure is halved and the effort on design description is more than doubled, in the experiment team.

    Ort, förlag, år, upplaga, sidor
    Neubiberg: Institut für Technische Produktentwicklung, Universität der Bundeswehr München, 2019
    Nyckelord
    Product/Service Systems design, Function-Behavior-Structure Ontology, Protocol analysis, Design support
    Nationell ämneskategori
    Människa-datorinteraktion (interaktionsdesign)
    Identifikatorer
    urn:nbn:se:liu:diva-156663 (URN)10.18726/2019_2 (DOI)9783943207378 (ISBN)
    Konferens
    The 2nd SIG conference in Human Behaviour in Design, April 23-24, 2019, Tutzing, Germany
    Tillgänglig från: 2019-05-06 Skapad: 2019-05-06 Senast uppdaterad: 2020-04-06Bibliografiskt granskad
  • Kock, Henrik
    et al.
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Pedagogik och sociologi. Linköpings universitet, Filosofiska fakulteten.
    Reineholm, Cathrine
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Pedagogik och sociologi. Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, HELIX Competence Centre.
    Organisatorisk förändringskompetens på arbetsplatser: Kunskapssammanställning 2020:42020Rapport (Refereegranskat)
    Abstract [sv]

    I denna rapport presenteras en kunskapssammanställning som inriktats mot forskning som undersöker vilka faktorer som anses som viktiga för att skapa en hög förändringskompetens på arbetsplatser. Denna kunskapssammanställning har genomförts på uppdrag av Myndigheten för arbetsmiljökunskap, inom ramen för ett regeringsuppdrag med syfte att sammanställa kunskap om framtidens arbetsliv. Syftet med kunskapssammanställningen är att undersöka vilka faktorer i empirisk forskning som beskrivs som viktiga för att använda, bibehålla och öka organisatorisk förändringskompetens. En viktig del i bestämningen av vad som innefattats i organisatorisk förändringskompetens är organisationens förmåga att ta tillvara befintlig kompetens och att genom lärande (individ, grupp och organisations lärande) utveckla organisatorisk förändringskompetens.

    Kunskapssammanställningen har utgått från en modell som framtagits vid Myndigheten för arbetsmiljökunskap. I ett första steg bestämdes syfte och frågeställningar, och därefter formulerades kriterier för vilka studier som skulle inkluderas respektive exkluderas i litteratursökningen. Kriterier för inkludering innefattade bland annat empiriska studier av planerad förändring i organisa­tioner/arbetsplatser, studier av befintlig kompetens och förmåga att utveckla eller använda kompetens, studier av lärande på individ-, grupp- och organisationsnivå, studier av individens välmående på arbetsplatsen samt studier av organisationers produktivitet/effektivitet. Ytterligare avgränsningar var att studierna skulle utgöras av vetenskapliga artiklar i internationella forskningstidskrifter med granskningsförfarande (eng. peer-reviewed), publicerade efter 1990 samt skrivna på engelska, svenska, norska eller danska. Exklusionskriterierna innefattade bland annat studier av framväxande och gradvisa förändringar, studier av kompetens med fokus på enskilda individer, studier av förändringsmotstånd och studier som enbart fokuserar på ohälsa. 

    Sökningarna genomfördes i två databaser: Scopus och Web of Science. Antalet träffar i Scopus var 1 650 och i Web of Science 944. Efter att dubbletter tagits bort återstod 1 953 unika artiklar, vilka screenades på titel och abstract. Totalt var det 142 studier som ansågs kräva fulltext för att avgöra om studien uppfyllde inklusionskriterierna. Därefter hämtades fulltexterna in och relevansgranskades. Totalt uppfyllde 42 studier samtliga relevansbedömningspunkter, vilka genomgick en kvalitetsbedömning utifrån vedertagna protokoll för kvantitativa och kvalitativa studier. Av de 42 kvalitetsgranskade studierna bedömdes 27 studier ha hög eller medelhög kvalitet, varav 13 var kvantitativa studier, två var studier med flera meteoder och 12 var kvalitativa studier. Totalt har således 27 studier ingått i granskningen. De inkluderade kvantitativa studierna har analyserats utifrån en narrativ analys, och de kvalitativa studierna har analyserats utifrån en konventionell innehållsanalys.

    Sammanfattningsvis visar studierna som ingår i kunskapssammanställningen att följande faktorer och förhållanden beskrivs som viktiga för att använda, bibehålla och utveckla organisatorisk förändringskompetens: ledning, chefer och förändringsagenter; medarbetarnas inställning till och tidigare erfarenheter av förändring; information, kommunikation och delaktighet före, under och efter förändringsprocesser; kompetens och möjligheter till lärande i förändringsprocesser. Forskning om organisatorisk förändringskompetens utgör i dag inget samlat forskningsområde, utan är spridd över ett antal områden och discipliner, särskilt forskning om ledarskap och forskning om organisatorisk förändring. Begreppet organisatorisk förändringskompetens saknar en mer bestämd och allmänt accepterad betydelse inom forskningen.

    Det största antalet studier i kunskapssammanställningen kan hänföras till det första området, det vill säga till ledning, chefer och förändringsagenter. Organisatorisk förändringskompetens i organisationer förefaller med andra ord att i hög grad knytas till chefers och förändringsagenters kompetens och agerande, snarare än att ses som organisationens samlade förmåga att driva planerad förändring. I linje med detta konstaterande förefaller det finnas ett motsvarande underskott på studier där medarbetares kapacitet att bidra analyseras. I de fall detta görs riktas fokus mot medarbetares förändringsmotstånd (”change resistance”) och hur detta kan förstås, snarare än på medarbetares förändringsmotivation och hur denna kan utvecklas. Studier av information, kommunikation och delaktighet före/under/efter organisatoriska förändringsprocesser och som en del av organisatorisk förändringskompetens belyses i flera studier. Informationen är viktig i alla nivåer av organisationen, och hur denna fråga hanteras är ett fortsatt viktigt forskningsområde, inte minst utifrån det som benämns som organisatoriskt meningsskapande. En viktig del i vår bestämning av vad som innefattas i organisatorisk förändringskompetens är organisationens förmåga att ta tillvara befintlig kompetens och att genom lärande (individ-, grupp- och organisationslärande) utveckla organisatorisk förändringskompetens. Här visar kunskapssammanställningen att det finns ett begränsat antal studier.

    Utifrån arbetet med sammanställningen har ett antal kunskapsluckor identifierats. Vissa av dessa kunskapsluckor som identifierats kan knytas till de forskningsmetoder som använts. Vad gäller kvantitativa studier ser vi en brist på longitudinella studier, att man följer en förändring över tid. En annan brist vi kan se är en låg svarsfrekvens, framför allt vid longitudinella studier. Vidare finns ett litet antal studier som studerat organisatorisk förändringsförmåga på flera nivåer. Beträffande de studier som genomförts inom både offentliga organisationer och privata företag kan analysen av kontextens betydelse drivas längre. Den kvalitativa forskning som här granskats har metodologiska begränsningar i flera avseenden. I flera fall handlar det om en begränsad empiri, både räknat som antal individer och antalet organisationer som studerats, och fallbeskrivningarna uppvisar svagheter som exempelvis otillräckliga beskrivningar av den organisatoriska kontexten. Fallstudier med kontrollgrupper (”case control”) och replikationer av tidigare studier finns inte representerade i de 27 studier som granskats. Studier med flera metoder förekommer endast i två av studierna. Studier av organisatorisk förändringskompetens utifrån den innebörd som beskrivits ovan är likaledes ovanliga. 

    Utifrån kunskapssammanställningen presenteras några allmänna råd. Alla organisationer har en mer eller mindre omfattande historia av planerade förändringar, både lyckade och mindre lyckade. Att lära av historien kan ses som en viktig del i att öka den organisatoriska förändringskompetensen. Ledare och förändringsagenter är naturligtvis viktiga men inte enbart för att leda förändring, utan också för att synliggöra och stödja användning av kompetens som finns i andra delar av organisationen – inte minst hos medarbetare. Förändringsmotstånd kan ses som en legitim reaktion eller nödvändig friktion i en illa genomförd eller feltänkt förändringsprocess, ett tillfälle att skapa öppenhet, möjlighet att påverka, utnyttja kunskap och erfarenhet som finns spridd i organisationen och därmed bygga förändringskompetens. Delaktighet i planering och genomförande kan öka motivationen och bidra till ett mer gemensamt meningsskapande, likaväl som delaktighet kan sättas under tryck på grund av tidsbrist eller andra faktorer som medför begränsningar. En viktig fråga att ställa är hur, och i vilka avseenden, ett aktivt deltagande i förändringsprocesser kan förväntas bidra till gynnsamma resultat, och inte minst stödja delaktighet i förändringsprocesser genom exempelvis ett ledarskap som stöder och möjliggör delaktighet hos anställda. Strategier och policyer är inte allt. Det krävs mer kraft på att utveckla metoder och stödja genomförande av planerade förändringar, snarare än att producera planer och strategier. Sett från det här perspektivet kan en viktig del av organisatorisk förändringskompetens ses som förmågan att bedöma och värdera organisatoriska förändringar, inklusive förmågan att anpassa och modifiera planer och strategier, och de metoder och tillvägagångssätt som används då förändringar implementeras.

  • Martinsson, Bengt-Göran
    et al.
    Linköpings universitet, Utbildningsvetenskap.
    Eriksson Barajas, Katarina
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Pedagogik och didaktik. Linköpings universitet, Utbildningsvetenskap.
    Svenskämnets och de moderna språkens didaktik2020Ingår i: Ämnesdidaktik vid Linköpings universitet / [ed] Karolina Muhrman, Linköping: Linköping University Electronic Press, 2020, s. 26-32Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • Westerholm, Gustaf
    Linköpings universitet, Institutionen för datavetenskap.
    Automatic Configuration of Aircraft and Simulators2020Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    For development, sales, verification and validation purposes, flight simulations of the Saab JAS 39 Gripen E/F are often performed. For these type of simulations, one needs to be able to choose both a specific aircraft variant and a specific simulation setup and then generate the appropriate build files to build the simulator. This configuration process is currently mainly done manually and has numerous points of variation, some of these are in:

    ·       ACSim Kernel which simulates the components and systems of the aircraft. Around 150 models can be chosen out of almost 1000 total.

    ·       ACCS, the aircraft computers containing the aircraft software applications. Here, dozens of configuration-specific applications can be included in a configuration.

    Restricting the configuration possibilities are relations and constraints between components, systems, models and applications, but also credentials of the user, limiting available options.

    In this thesis it is examined to what degree this configuration process can be automated with a variant management tool, such as pure::variants, and possible ways of implementation are presented. A conclusion is that that the configuration of ACSim Kernel build files can be automated to a high degree, and for the ACCS system architecture studied in this thesis, build files can be automated to a lower degree. It is also shown how pure::variants can be used to filter its models for secrecy purposes, and how helpful system properties can be represented in pure::variants models. A suggestive example of how pure::variants can be used with short implementation time is provided and more labour intensive implementation suggestions are discussed.

  • Lundin, Jennifer
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Affärsrätt. Linköpings universitet, Filosofiska fakulteten.
    Rydh, Dennis
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Affärsrätt. Linköpings universitet, Filosofiska fakulteten.
    Framtida beskattning av robotar: En studie i förhållande till kraven på god skattelagstiftning och befintliga beskattningsmetoder.2019Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Under de senaste åren har en internationell diskussion angående robotskatt blossat upp. Den tekniska utvecklingen sker snabbare än aldrig förr. Redan i dagsläget finns det teknik som möjliggör att hälften av dagens arbetsuppgifter skulle kunna automatiseras. Cirka 60 procent av Sveriges skatteintäkter kommer i dag från skatt på förvärvsarbete. Skulle hälften av dagens arbetsuppgifter automatiseras riskerar således staten och kommunerna att förlora en stor del skatteintäkter. Debatten är för närvarande i ett stadium då det diskuteras huruvida robotar bör eller inte bör beskattas. I detta studium anlägger vi ett skatterättsligt perspektiv på den debatterade frågan med syftet att tillföra debatten ytterligare en dimension. Svårigheterna med att utforma en robotskattelag är dels att definiera begreppet robot skatterättsligt dels att utreda om en robotskattelag skulle vara förenlig med de krav som ställs på en god skattelagstiftning. Kraven som ställs på en god skattelagstiftning verkar likt krafterna i ett spänningsfält. Vissa av kraven är till och med motstridiga och en god skattelagstiftning uppvisar en balans mellan dessa krav. I uppsatsen utreder vi huruvida en robotskatt, då den utformas i enlighet med någon av de tre befintliga beskattningsmetoderna punktskatt, objektskatt samt inkomstskatt på schablonintäkt, uppvisar en acceptabel balans mellan de krav som ställs på en god skattelagstiftning. Genom den analys vi företagit i uppsatsen har vi kommit fram till att en robotpunktskatt skulle vara relativt ineffektiv med hänsyn robotskattens fiskala primärmål. Däremot har vi kommit fram till att en robotobjektskatt samt inkomstskatt på robotschablonintäkt skulle kunna uppvisa en acceptabel balans mellan de krav som ställs på en god skattelagstiftning.

  • Disputation: 2020-04-30 13:15 I:101, I-Building, LinköpingBeställ onlineKöp publikationen >>
    Palmqvist, Lisa
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Handikappvetenskap. Linköpings universitet, Filosofiska fakulteten.
    Time to Plan: How to support everyday planning in adolescents with intellectual disability2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Barn och ungdomar med intellektuell funktionsnedsättning (IF) har svårt med sina exekutiva funktioner och dagliga planeringsuppgifter. Litteraturen kan dock inte förklara om individer med IF presterar enligt deras utvecklingsnivå eller inte. Studierna i denna avhandling undersökte om livserfarenhet kan vara en bidragande faktor till varför denna skillnad ses i litteraturen. Planeringsförmågan kan förbättras genom att använda externt eller internt stöd. Hjälpteknik för kognition (HM-K) är ett exempel på externt stöd. Denna avhandling undersökte hur HM-K används i en vardaglig planeringssituation vilket inte har undersökts tidigare. Vidare undersökte denna avhandling om de interna stöden för kognitiva förmågor och livserfarenhet korrelerar med planeringsförmåga hos ungdomar med IF, och om planeringsförmåga kan förbättras med hjälp av ett kognitivt träningsprogram för vardagsplanering. Resultaten visade att HM-K stödde kognitiva funktioner, men att barnen inte formulerade planerna själva. Vidare stöder resultaten skillnadsmodellen för IF eftersom planering korrelerade med olika kognitiva mått och livserfarenhet hos ungdomar med IF jämfört med barn med en typisk utveckling. Ungdomar med IF blev bättre på planeringsuppgifterna i träningsprogrammet, men inga överföringseffekter till otränade planeringsuppgifter hittades. Avslutningsvis så stöds planeringen av externa och interna stöd. HM-K måste dock utformas och förskrivas på ett sätt som ökar självständighet. Praktiker bör aktivt stödja träning av planering och bör vara försiktiga när de inför kognitiva insatser om överföringsgapet är för stort.

    Delarbeten
    1. Parents act as intermediary users for their children when using assistive technology for cognition in everyday planning: Results from a parental survey
    Öppna denna publikation i ny flik eller fönster >>Parents act as intermediary users for their children when using assistive technology for cognition in everyday planning: Results from a parental survey
    2019 (Engelska)Ingår i: Assistive technology, ISSN 1040-0435, E-ISSN 1949-3614, s. 1-9Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Assistive Technology for Cognition (ATC) is employed by children with and without disabilities. However, how the ATC is used in everyday life has not been studied. The current study investigated ATC-usage in everyday planning in three groups: 1) children qualifying for Swedish habilitation centers (ID/ASD), 2) children with disability not qualifying for habilitation service (ADHD), and 3) children with typical development (TD). A parental survey was conducted (n = 192) and answers were analyzed with statistical tests and inductive thematic text analysis. Results showed that all groups used ATC, most in the Habilitation group and least in the TD group. According to parents, ATC supported cognitive functions in all groups, but it became evident that the parents were responsible for planning by setting up the ATC, whilst the children merely executed the plans. This was linked to several limitations, for example the design was not appropriately adapted for these groups. The implications for the practitioners are 1) evaluate the users? cognitive abilities and choose an ATC suitable for that individual rather focusing on the diagnosis, and 2) follow up usage to see if it is the parent or the child that are using the ATC.

    Ort, förlag, år, upplaga, sidor
    Taylor & Francis, 2019
    Nyckelord
    Activities of daily living, assessment, cognitive impairment, developmental disability, electronic aids to daily living, usability
    Nationell ämneskategori
    Pediatrik
    Identifikatorer
    urn:nbn:se:liu:diva-164915 (URN)10.1080/10400435.2018.1522523 (DOI)
    Tillgänglig från: 2020-04-01 Skapad: 2020-04-01 Senast uppdaterad: 2020-04-01Bibliografiskt granskad
    2. Cognitive abilities and life experience in everyday planning in adolescents with intellectual disabilities: Support for the difference model
    Öppna denna publikation i ny flik eller fönster >>Cognitive abilities and life experience in everyday planning in adolescents with intellectual disabilities: Support for the difference model
    2020 (Engelska)Ingår i: Journal of Intellectual Disability Research, ISSN 0964-2633, E-ISSN 1365-2788Artikel i tidskrift (Refereegranskat) Epub ahead of print
    Abstract [en]

    Background The literature on planning ability in individuals with intellectual disability (ID) provides no clarity on whether their ability matches their mental age (MA) or not. Perhaps can planning experience explain the mixed results. The current study investigated to what extent cognitive abilities and life experience can explain everyday planning ability in individuals with ID and to what extent results from everyday planning tasks support the developmental or the difference model of ID. Method Planning tests, cognitive ability tasks and a self-rated life experience form were administered to 71 adolescents with ID and 62 children with a typical development matched on MA. Results Adolescents with ID exhibited planning ability according to their MA. Regression analyses showed that the predictors of planning differed between the groups. The cognitive measures could predict planning in both groups, but life experience only contributed positively to planning in the MA group, whereas chronological age was negatively correlated with successful planning in the ID group. Conclusions and discussion The results support the difference model of ID. When matched on MA, the individuals with ID will solve the planning task in a qualitatively different manner. Additionally, the participants with ID could not utilise their life experience when solving the planning task, contrary to the MA group. Practitioners should be aware that individuals with ID might need more everyday planning training throughout adolescence. To support adolescents with ID, practitioners may focus on supporting the individuals cognitive abilities rather than relying on their prior knowledge.

    Ort, förlag, år, upplaga, sidor
    WILEY, 2020
    Nyckelord
    cognitive abilities; difference model; errand task; everyday planning; intellectual disability
    Nationell ämneskategori
    Arbetsterapi
    Identifikatorer
    urn:nbn:se:liu:diva-163409 (URN)10.1111/jir.12710 (DOI)000505491500001 ()31898385 (PubMedID)
    Anmärkning

    Funding Agencies|Stiftelsen Savstaholm [ST 2016-030]

    Tillgänglig från: 2020-02-04 Skapad: 2020-02-04 Senast uppdaterad: 2020-04-01
  • Eriksson, John
    Linköpings universitet, Institutionen för datavetenskap.
    Machine Learning for Predictive Maintenance on Wind Turbines: Using SCADA Data and the Apache Hadoop Ecosystem2020Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis explores how to implement a predictive maintenance system for wind turbines in Apache Spark using SCADA data. How to balance and scale the data set is evaluated, together with the effects of applying the algorithms available in Spark mllib to the given problem. These algorithms include Multilayer Perceptron (MLP), Linear Regression (LR), Random Forest (RF), Decision Tree (DT), Support Vector Machine (SVM) and Gradient Boosted Tree (GBT). This thesis also evaluates the effects of applying stacking and bagging algorithms in an attempt to decrease the variance and improve the metrics of the model. It is found that the MLP produces the most promising model for predicting failures on the given data set and that stacking multiple MLP models is a good way of producing a model with a lower variance than the individual base models. In addition to this, a function that creates a savings estimation is developed. Using this function, a time window function that explores the decisiveness of a model is created. The conclusion is made that a model is more decisive if the failure it predicts occurs in a turbine where it has been trained on failure data from that same component, indicating that there are unknown variables that affect the sensor data.

  • Disputation: 2020-05-05 09:00 Berzeliussalen, Building 463, LinköpingBeställ onlineKöp publikationen >>
    Toll, Rani
    Linköpings universitet, Institutionen för biomedicinska och kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Närsjukvården i centrala Östergötland, Akutkliniken i Linköping.
    To See or Not to See: A Study on Capillary Refill2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Background: Assessment of the critically ill is traditionally based on vital signs (blood pressure, pulse, respiratory rate, temperature and level of consciousness). Altered vital signs are, however, late indicators of deranged hemodynamics pointing to a need for additional, more sensitive markers of circulatory compromise. In the beginning of the 20th century, the capillary refill (CR) time evolved as a possible, non-invasive adjunct to early prediction of the outcome in the critically ill. The manoeuvre entails application of blanching pressure on the skin of the finger pulp or sternum for 5 seconds. After release of the pressure, the observer estimates time in seconds for the skin to return to original colour. This time is hypothesized to reflect the dynamics of the microcirculation and its possible connection with hemodynamics. In the 1980s the “normal capillary refill time” was set to < 2 seconds and later extended to 3 seconds, without a clear scientific foundation. Naked-eye estimations of CR time met increasing scepticism in the 1990s due to subjectivity and poor prognostic value for shock or death. Several basic traits, such as age and sex, as well as ambient temperature, were also shown to independently influence the CR time. Various methods have evolved with the capability to measure CR time quantitatively, one of which is Polarisation Spectroscopy Imaging (PSI). PSI measures the Red Blood Cell (RBC) concentration in tissue (e.g. the skin) and can be used to measure CR time.

    Objectives: The purpose of this study was to establish basic characteristics for quantified CR (qCR), identify possible influencing factors in healthy subjects and to investigate how this relates to current practice. We also sought to identify technical demands for transfer of the technique into clinical studies. In paper I we analysed the (qCR) time characteristics at 5 different skin sites (forehead, sternum, volar forearm, finger pulp and dorsum finger). The objective of paper II was to investigate the inter- and intra-observer variability of naked eye CR assessments of different professions, nurses, doctors and secretaries (representing laymen). In paper III we observed the effect of low ambient temperature on the qCR time in different skin sites. In paper IV, we transferred the equipment from a laboratory to a clinical setting in the Emergency Department (ED) for application on potentially critically ill patients. In this study we evaluated the most important factors determining a reliable data collection and influencing the amount of data possible to analyse.

    Methods: qCR time was measured in a total of 38 volunteers and 10 patients in different skin sites (2-5 skin sites) at different ambient temperatures. PSI (TiVi 600 and 700, WheelsBridge AB, Linköping, Sweden) was used to determine the rapid temporal changes in RBC concentration in skin during the CR manoeuvre. Films using a range of the first measurements from paper I were shown for assessment to 48 observers working in the ED.

    Results: In paper I we could delineate qCR curves and suggest 2 possible equivalents to the naked-eye observed CR time which we named Time to Return to Baseline 1 (tRtB1) and Time to Peak (tpk). We demonstrated differences in qCR-curves depending on skin site and possibly due to skin temperature. In paper II we showed a poor inter- and intra-observer reproducibility in visually estimating the CR time regardless of profession (clinicians or laymen). Paper III demonstrated a rapid effect of ambient temperature on qCR time in peripheral skin sites such as finger pulp. The forehead, regarded as a more central skin site was the most temperature stable site and showed least variability in qCR time as determined using tRtB1. Paper IV, a study on patients in an ED setting, yielded assayable data in 80% of the measurements. We identified critical performance parameters to address in the further development of a more robust, easy-to-use device for future validation of the possible relevance of qCR in patient triage and monitoring.

    Conclusions: CR time can be quantified using PSI. Quantified CR time demonstrated a large variability between different skin sites, specifically, skin temperature was shown to be an important factor influencing qCR time, particularly at the fingertip. Naked-eye estimates of CR time were highly variable, both within and between observers. Agreement between quantified CR time and naked-eye estimates was poor. The prototypic PSI technique was feasible in a clinical setting and, with further improvements, clinical evaluation of qCR in relation to relevant patient outcomes will be possible.

    Delarbeten
    1. Reflectance spectroscopy: to shed new light on the capillary refill test
    Öppna denna publikation i ny flik eller fönster >>Reflectance spectroscopy: to shed new light on the capillary refill test
    Visa övriga...
    2018 (Engelska)Ingår i: Journal of Biophotonics, ISSN 1864-063X, E-ISSN 1864-0648, Vol. 11, nr 1, artikel-id e201700043Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    To use Bioengineering methodology is used to achieve, at five anatomical sites, a detailed, quantitative assessment of the return of blood content to the blanched area, during the Capillary Refill (CR) test. An observational, non-randomized, experimental study on 23 healthy subjects (14 females) was performed in our climate controlled skin physiology laboratory. Our main outcome measures were based on the chronological assessment and quantification of red blood cell concentration (RBC) after the release of blanching pressure in the CR test, using Tissue Viability Imaging (TiVi), a digital photographic technique based on polarisation spectroscopy. TiVi enabled collection of detailed data on skin RBC concentration during the CR test. The results were shown as curves with skin blood concentration (TiVi-value) on the y-axis and the time on the x-axis. Quantitative CR responses showed site and temperature variability. We also suggest possible objective endpoint values from the capillary refill curve. Detailed data on skin RBC concentration during the CR test is easily obtained and allows objective determination of end points not possible to achieve by naked eye assessment. These findings have the potential to place the utility of the CR test in a clinical setting in a new light. Picture: Regular photograph and TiVi Image showing CR test and corresponding graph for the CR response. [GRAPHICS] .

    Ort, förlag, år, upplaga, sidor
    Wiley-VCH Verlagsgesellschaft, 2018
    Nyckelord
    Capillary refill; microvasculature; circulation; skin imaging; gender variability; blood concentration
    Nationell ämneskategori
    Dermatologi och venereologi
    Identifikatorer
    urn:nbn:se:liu:diva-145478 (URN)10.1002/jbio.201700043 (DOI)000425294600022 ()28544641 (PubMedID)2-s2.0-85019540776 (Scopus ID)
    Tillgänglig från: 2018-03-05 Skapad: 2018-03-05 Senast uppdaterad: 2020-04-01Bibliografiskt granskad
    2. Man versus machine: comparison of naked-eye estimation and quantified capillary refill
    Öppna denna publikation i ny flik eller fönster >>Man versus machine: comparison of naked-eye estimation and quantified capillary refill
    2019 (Engelska)Ingår i: Emergency Medicine Journal, ISSN 1472-0205, E-ISSN 1472-0213, Vol. 36, nr 8, s. 465-471Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Background Capillary refill (CR) time is traditionally assessed by naked-eye inspection of the return to original colour of a tissue after blanching pressure. Few studies have addressed intra-observer reliability or used objective quantification techniques to assess time to original colour. This study compares naked-eye assessment with quantified CR (qCR) time using polarisation spectroscopy and examines intra-observer and interobserver agreements in using the naked eye. Method A film of 18 CR tests (shown in a random fixed order) performed in healthy adults was assessed by a convenience sample of 14 doctors, 15 nurses and 19 secretaries (Department of Emergency Medicine, Linkoping University, September to November 2017), who were asked to estimate the time to return to colour and characterise it as fast, normal or slow. The qCR times and corresponding naked-eye time assessments were compared using the Kruskal-Wallis test. Three videos were shown twice without observers knowledge to measure intra-observer repeatability. Intra-observer categorical assessments were compared using Cohens Kappa analysis. Interobserver repeatability was measured and depicted with multiple-observer Bland-Altman plotting. Differences in naked-eye estimation between professions were analysed using ANOVA. Results Naked-eye assessed CR time and qCR time differ substantially, and agreement for the categorical assessments (naked-eye assessment vs qCR classification) was poor (Cohens kappa 0.27). Bland-Altman intra-observer repeatability ranged from 6% to 60%. Interobserver agreement was low as shown by the Bland-Altman plotting with a 95% limit of agreement with the mean of +/- 1.98 s for doctors, +/- 1.6 s for nurses and +/- 1.75 s for secretaries. The difference in CR time estimation (in seconds) between professions was not significant. Conclusions Our study suggests that naked-eye-assessed CR time shows poor reproducibility, even by the same observers, and differs from an objective measure of CR time.

    Ort, förlag, år, upplaga, sidor
    BMJ PUBLISHING GROUP, 2019
    Nationell ämneskategori
    Anestesi och intensivvård
    Identifikatorer
    urn:nbn:se:liu:diva-159714 (URN)10.1136/emermed-2018-207948 (DOI)000478913300006 ()31308133 (PubMedID)
    Anmärkning

    Funding Agencies|Region Ostergotland [LIO-532001, LIO-700271]

    Tillgänglig från: 2019-08-19 Skapad: 2019-08-19 Senast uppdaterad: 2020-04-01
    3. A cool response: the influence of ambient temperature on capillary refill time
    Öppna denna publikation i ny flik eller fönster >>A cool response: the influence of ambient temperature on capillary refill time
    Visa övriga...
    2018 (Engelska)Ingår i: Journal of Biophotonics, ISSN 1864-063X, E-ISSN 1864-0648, Vol. 11, nr 6Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Objective

    To describe the effect of low ambient temperature on skin temperature and capillary refill (CR) time in forehead, sternum and finger pulp.

    Methods

    An observational, nonrandomized experimental study on 15 healthy subjects (6 females) in a cold room (8°C). Outcome measures were skin temperature and quantified CR test after application of a standardized blanching pressure (9 N/cm2) using digital photographic polarization spectroscopy to generate CR times.

    Results

    The finger pulp showed marked temperature fall and prolonged CR times (>10 seconds). The CR registrations of the forehead and sternum were more comparable to curves observed in a control material at room temperature, and skin temperature falls were less marked. CR times were not prolonged in forehead measurements. At the sternum, some individuals showed CR times beyond guideline recommendations despite only a marginal reduction in skin temperature.

    Conclusions

    Low ambient temperature is a strong independent factor for CR time at peripheral sites. Reservation about sternum as a site of measurement is warranted since cold provocation produced prolonged CR times in some individuals. We found that the forehead is the most thermostable of the 3 sites and thus the preferred site to avoid ambient temperature artifact in measuring CR time.

    Ort, förlag, år, upplaga, sidor
    Wiley-VCH Verlagsgesellschaft, 2018
    Nationell ämneskategori
    Atom- och molekylfysik och optik
    Forskningsämne
    Katastrofmedicin
    Identifikatorer
    urn:nbn:se:liu:diva-145527 (URN)10.1002/jbio.201700371 (DOI)000434641700017 ()29384267 (PubMedID)
    Anmärkning

    Funding agencies: Socialstyrelsen; Region Ostergotland

    Tillgänglig från: 2018-03-05 Skapad: 2018-03-05 Senast uppdaterad: 2020-04-01Bibliografiskt granskad
  • Karabag, Solmaz Filiz
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Projekt, innovationer och entreprenörskap. Linköpings universitet, Tekniska fakulteten.
    An Unprecedented Global Crisis! The Global, Regional, National, Political, Economic and Commercial Impact of the Coronavirus Pandemic2020Ingår i: Journal of Applied Economics and Business Research, E-ISSN 1927-033X, Journal of Applied Economics and Business Research, E-ISSN 1927-033X, Vol. 10, nr 1, s. 1-6Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The proliferation of the coronavirus has created a global, regional, national, political, societal, economic and commercial crisis. The coronavirus crisis not only can be characterized as a disruptive period of instability, uncertainty, and danger but also can be perceived as a period of accelerated diffusion of digital technologies, micro-level initiatives, and a consideration of established resource-intensive forms. This paper discusses the possible impact of coronavirus pandemic crisis in the short and long term and call for research in many social and technical science fields such as political science, economics, business, management and technology management. By this paper, I intend to foster an exchange of theoretical ideas and empirical research across these topics at JAEBR and other leading journals.  

  • Atkins, Hannah
    Linköpings universitet, Institutionen för samhälls- och välfärdsstudier.
    Healthy Enough to Enter?: Exploring the nexus of the body and the border through South African visa medical requirements2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Visitors to South Africa wishing to stay in the country for longer than three months are required to submit a medical report which makes room for a host of physical and mental “defects”, including leprosy, venereal disease, trachoma, disabilities and mental health disorders ranging from addictions to epilepsy. The form appears to be an object that points to a multiplicity of interpretations as well as inconsistencies. It is a piece of paper encountered by several actors key to the immigration process – policy makers, visa applicants, doctors and lawyers – and through its use, showcases the tensions that exist between these sites. Furthermore, as a mandatory visa document, the medical form directs us to examine the relationship between the individual body and the exercise of state power.

  • Lee Lindgren, Ylva
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Pedagogik och sociologi.
    Att interagera med en robot: En förstudie om förhållandet mellan den moderna människan och högteknologi2019Självständigt arbete på avancerad nivå (magisterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Högteknologin i samhället idag är ständigt närvarande. Teknologiska system som lagrar information som nyttjas till individanpassad reklam och automatiserar flygplan som idag kan drivas utan medverkan av en pilot. En artificiell intelligens som hovrar i automatiska samtals- och chattrobotar och effektiviserar en mängd yrkesfält med automatiserade lösningar. Syftet med denna studie ligger i människans föreställning om mötet och interaktionen med högteknologi. Etiskt-, emotionellt-, praktiskt- och relationsmässigt har undersökningen sökt sig till en förståelse för individers förhållningssätt till fenomenet. Det har genomförts en kvalitativ innehållsanalys på åtta respondenter och det erhållna datamaterialet har tolkats med utvalda sociologiska teorier hos Marx, Weber, Bauman, Foucault, Ottomeyer och Ritzer.  Resultatet från studien visar på att det finns en skeptism och motvilja till den teknologiska utvecklingen och upplevelser av exponering och övervakning. Utifrån empirin har egna vidareutvecklingar i anslutning till den sociologiska teorin kläckts: Det allseende ögat, den ensidiga relationen samt interaktion mellan bortvända ryggar.  

  • Nuñez, Alberto
    Linköpings universitet, Institutionen för datavetenskap, Interaktiva och kognitiva system.
    Human–computer interaction in second language word acquisition: A qualitative study on Peruvians’ use of computers to learn new words in Swedish2018Självständigt arbete på grundnivå (kandidatexamen), 12 poäng / 18 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The program for language learning Svenska för invandrare (Swedish for newcomers) has only a small amount of students who complete the program successfully. The use of computers could help students and educators increase the amount of success. A review of the research on second language word acquisition in human–computer interaction suggests that there is lack of studies, especially qualitative ones, in the area. For this reason, the following pilot study explores the possibilities of using audio-visual recordings of open interviews during tasks in order to analyze human–computer interaction and discuss how it enhances or limits Swedish as a second language word acquisition. With this ambition, qualitative information about how four participants looked up the meaning of a few, selected, words on a computer was gathered through recording their interactions and comments. The results of the study are discussed from a cognitive perspective to determine which interactions enhanced, or limited, second language word acquisition. The results preliminary suggest that the use of images and dictionaries of synonyms could enhance word acquisition. However, the use of strategies to avoid writing or holding unknown words in memory, the use of online translating services, changing prefixes and suffixes to generate new queries, and the use of a search engine’s results as an information source, could limit L2 word acquisition for this particular group.

  • Härnström, Felix
    Linköpings universitet, Institutionen för datavetenskap.
    Product Line Engineering for large-scale simulators: An exploratory case study2020Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This thesis takes a process-centric approach to Product Line Engineering (PLE) with the purpose of evaluating the suitability of PLE practices and processes in the context of large-scale industrial simulator products. This human-centered approach sets itself apart from previous research on the subject which has been mostly focused on architectural and technical aspects of PLE. The study took place at Saab, a Swedish aerospace and defense company whose primary product is the Saab 39 Gripen fighter aircraft. The study was conducted as a series of interviews with participants across three product lines, each responsible for a different line of simulators. By investigating their current working processes using the Family Evaluation Framework, a maturity rating was derived for each product line. This maturity rating was then considered alongside commonly reported issues and experiences in order to evaluate the usefulness of PLE practices for each product line. It was found that the studied organization could likely benefit from implementing PLE. PLE and the Family Evaluation Framework promotes practices that would alleviate some of the major issues found in the studied organization such as unclear requirements, issues with product integration and external dependencies, and a lack of quantitative data. Due to the relative immaturity of PLE processes in the studied organization, these conclusions are based on a review of existing literature and the stated goals and practices of PLE applied to the context of the studied organization.

  • Fritz, Karin
    Linköpings universitet, Institutionen för systemteknik, Datorseende.
    Instance Segmentation of Buildings in Satellite Images2020Självständigt arbete på avancerad nivå (masterexamen), 300 hpStudentuppsats (Examensarbete)
    Abstract [en]

    When creating a photo realistic 3D model of the world using satellite imagery, image classification is an important part of the process. In this thesis the specificpart of automated building extraction is investigated. This is done by investi-gating the difference in performance between the methods instance segmentation and semantic segmentation for extraction of building footprints in orthorectified imagery. Semantic segmentation of the images is solved by using U-net, a Fully Convolutional Network that outputs a pixel-wise segmentation of the image. Instance segmentation of the images is done by a network called Mask R-CNN.The performance of the models are measured using precision, recall and the F1 score, which is the harmonic mean between precision and recall. The resulting F1 score of the two methods are similar, with U-net achieving a the F1 score of 0.684 without any post processing. Mask R-CNN achieves the F1 score of 0.676 without post processing.

  • Lidh, Josefin
    Linköpings universitet, Institutionen för datavetenskap.
    En fallstudie om vårdpersonals acceptans av en videomötestjänst2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    År 2025 ska Sverige vara bäst i världen på att utnyttja och ta tillvara på de möjligheter som finns med e-hälsa och digitalisering, enligt överenskommelsen Vision e-hälsa (SKL & Socialdepartementet, 2017). Region Östergötland är en av de regioner som strävar efter att hänga med i den digitala utvecklingen och en av satsningarna är att kunna erbjuda regionens invånare digitala vårdbesök. Pilotprojektet Digitala Vårdcentralen som pågått sedan januari 2018 gör det möjligt för patienter att via video genomföra vårdbesök med läkare och fysioterapeuter. Studien syftar till att utforska hur en framtida videomötestjänst skulle kunna utformas vad gäller dess egenskaper och behov i relation till vårdpersonal inom Region Östergötland, samt undersöka vilka faktorer som påverkar vårdpersonalens acceptans av och intention till att använda en sådan tjänst. Studien genomförs i form av en kvalitativ fallstudie och fungerar som ett första steg i utformningen av en videomötestjänst med utgångspunkt i tjänstedesign och Technology Acceptance Model (TAM). Denna studie bidrog med att föreslå ett antal egenskaper och väsentliga områden som en framtida videomötestjänst bör ta hänsyn till och sträva efter för att möta funna behov. Studiens utgångspunkt i det teoretiska ramverket TAM bidrog till ett antal påverkande faktorer för vårdpersonals acceptans av och intention till att använda vårdbesök via video. Att analysera studiens intervjudata med stöd från två förhållningssätt bidrog till en djupare förståelse för vårdpersonalen gentemot en videomötestjänst samt den komplexa kontext som de befinner sig i. Slutligen kunde studien bidra till ett antal rekommendationer för att en framtida videomötestjänst ska accepteras, vilja användas och möta vårdpersonalens behov.

  • Sandstedt, Mårten
    et al.
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för diagnostik och specialistmedicin. Region Östergötland, Diagnostikcentrum, Röntgenkliniken i Linköping. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Linköpings universitet, Medicinska fakulteten.
    Henriksson, Lilian
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för diagnostik och specialistmedicin. Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Region Östergötland, Diagnostikcentrum, Röntgenkliniken i Linköping.
    Janzon, Magnus
    Linköpings universitet, Institutionen för medicin och hälsa, Avdelningen för hälso- och sjukvårdsanalys. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Hjärt- och Medicincentrum, Kardiologiska kliniken US.
    Nyberg, Gusten
    Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Engvall, Jan
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för diagnostik och specialistmedicin. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Hjärt- och Medicincentrum, Fysiologiska kliniken US. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    de Geer, Jakob
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för diagnostik och specialistmedicin. Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV. Region Östergötland, Diagnostikcentrum, Röntgenkliniken i Linköping.
    Alfredsson, Joakim
    Linköpings universitet, Institutionen för medicin och hälsa, Avdelningen för kardiovaskulär medicin. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Hjärt- och Medicincentrum, Kardiologiska kliniken US.
    Persson, Anders
    Linköpings universitet, Institutionen för hälsa, medicin och vård, Avdelningen för diagnostik och specialistmedicin. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Röntgenkliniken i Linköping. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Evaluation of an AI-based, automatic coronary artery calcium scoring software2020Ingår i: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 30, nr 3, s. 1671-1678Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objectives

    To evaluate an artificial intelligence (AI)–based, automatic coronary artery calcium (CAC) scoring software, using a semi-automatic software as a reference.

    Methods

    This observational study included 315 consecutive, non-contrast-enhanced calcium scoring computed tomography (CSCT) scans. A semi-automatic and an automatic software obtained the Agatston score (AS), the volume score (VS), the mass score (MS), and the number of calcified coronary lesions. Semi-automatic and automatic analysis time were registered, including a manual double-check of the automatic results. Statistical analyses were Spearman’s rank correlation coefficient (⍴), intra-class correlation (ICC), Bland Altman plots, weighted kappa analysis (κ), and Wilcoxon signed-rank test.

    Results

    The correlation and agreement for the AS, VS, and MS were  = 0.935, 0.932, 0.934 (p < 0.001), and ICC = 0.996, 0.996, 0.991, respectively (p < 0.001). The correlation and agreement for the number of calcified lesions were  = 0.903 and ICC = 0.977 (p < 0.001), respectively. The Bland Altman mean difference and 1.96 SD upper and lower limits of agreements for the AS, VS, and MS were − 8.2 (− 115.1 to 98.2), − 7.4 (− 93.9 to 79.1), and − 3.8 (− 33.6 to 25.9), respectively. Agreement in risk category assignment was 89.5% and κ = 0.919 (p < 0.001). The median time for the semi-automatic and automatic method was 59 s (IQR 35–100) and 36 s (IQR 29–49), respectively (p < 0.001).

    Conclusions

    There was an excellent correlation and agreement between the automatic software and the semi-automatic software for three CAC scores and the number of calcified lesions. Risk category classification was accurate but showing an overestimation bias tendency. Also, the automatic method was less time-demanding.

    Key Points

    • Coronary artery calcium (CAC) scoring is an excellent candidate for artificial intelligence (AI) development in a clinical setting.

    • An AI-based, automatic software obtained CAC scores with excellent correlation and agreement compared with a conventional method but was less time-consuming.

  • Fuchs, Alexander
    et al.
    Region Östergötland, Diagnostikcentrum, Röntgenkliniken i Linköping. KTH, Sweden.
    Berg, Niclas
    KTH, Sweden.
    Wittberg, Lisa Prahl
    KTH, Sweden.
    Stenosis Indicators Applied to Patient-Specific Renal Arteries without and with Stenosis2019Ingår i: FLUIDS, ISSN 2311-5521, Vol. 4, nr 1, artikel-id 26Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pulsatile flow in the abdominal aorta and the renal arteries of three patients was studied numerically. Two of the patients had renal artery stenosis. The aim of the study was to assess the use of four types of indicators for determining the risk of new stenosis after revascularization of the affected arteries. The four indicators considered include the time averaged wall shear stress (TAWSS), the oscillatory shear index (OSI), the relative reference time (RRT) and a power law model based in platelet activation modeling but applied to the endothelium, named endothelium activation indicator (EAI). The results show that the indicators can detect the existing stenosis but are less successful in the revascularized cases. The TAWSS and, more clearly, the EAI approach seem to be better in predicting the risk for stenosis relapse at the original location and close to the post-stenotic dilatation. The shortcomings of the respective indicators are discussed along with potential improvements to endothelial activation modeling and its use as an indicator for risks of restenosis.

  • Vaidyalingam Arumugam, Karthik
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Konstruktionsmaterial.
    Effect of Process Parameters on Contour Properties in Inconel 718 Structures Fabricated by Electron Beam Melting2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Additive Manufacturing (AM), commonly known as 3D printing is a production method that utilises repeated addition of layers in order to produce a final shape. AM utilises less raw material and does not have drawbacks such as tool wear and material wastage as seen in conventional machining. However, they do have drawbacks such as poor surface and internal defects.  A common practice in AM is the fabrication of contour and bulk region using separate parameters.

     The aim of this project was to study the effects of various process parameters on the contour properties. The process parameters considered were scanning speed, beam current and focus offset. The Nickel alloy Inconel 718 was utilised in Electron Beam Melting (EBM) to fabricate the test specimen. The samples used in this project were in an as-built condition which was priorly subjected to tensile testing for a different project. The tests performed in this project are hardness testing and microstructural investigation about grains, precipitates and the various defects.

     The test results helped to understand the effect of various process parameters on the hardness and microstructure of the samples. The samples with lower scanning speed had higher hardness and lesser lack of fusion than samples with higher speed. In the case of varying beam current, the samples with higher beam current had higher hardness values and fewer lack of fusions. Similarly, the effects of varying two or more process parameters were also studied and their findings recorded. The microstructure consisted of a large number of shrinkage porosities in the bulk and contour regions. The presence of Niobium rich precipitates at grain boundaries and the grain structure for various process parameters were identified and recorded.

  • Azeez, Ahmed
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanik och hållfasthetslära. Linköpings universitet, Tekniska fakulteten.
    Eriksson, Robert
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanik och hållfasthetslära. Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Tekniska fakulteten.
    Leidermark, Daniel
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanik och hållfasthetslära. Linköpings universitet, Tekniska fakulteten.
    Calmunger, Mattias
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Konstruktionsmaterial. Linköpings universitet, Tekniska fakulteten.
    Low cycle fatigue life modelling using finite element strain range partitioning for a steam turbine rotor steel2020Ingår i: Theoretical and applied fracture mechanics (Print), ISSN 0167-8442, E-ISSN 1872-7638, Vol. 107Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Materials made for modern steam power plants are required to withstand high temperatures and flexible operational schedule. Mainly to achieve high efficiency and longer components life. Nevertheless, materials under such conditions experience crack initiations and propagations. Thus, life prediction must be made using accurate fatigue models to allow flexible operation. In this study, fully reversed isothermal low cycle fatigue tests were performed on a turbine rotor steel called FB2. The tests were done under strain control with different total strain ranges and temperatures (20 °C to 625 °C). Some tests included dwell time to calibrate the short-time creep behaviour of the material. Different fatigue life models were evaluated based on total life approach. The stress-based fatigue life model was found unusable at 600 °C, while the strain-based models in terms of total strain or inelastic strain amplitudes displayed inconsistent behaviour at 500 °C. To construct better life prediction, the inelastic strain amplitudes were separated into plastic and creep components by modelling the deformation behaviour of the material, including creep. Based on strain range partitioning approach, the fatigue life depends on different damage mechanisms at different strain ranges at 500 °C. This allows for the formulation of life curves based on either plasticity-dominated damage or creep-dominated damage. At 600 °C, creep dominated while at 500 °C creep only dominates for higher strain ranges. The deformation mechanisms at different temperatures and total strain ranges were characterised by scanning electron microscopy and by quantifying the amount of low angle grain boundaries. The quantification of low angle grain boundaries was done by electron backscatter diffraction. Microscopy revealed that specimens subjected to 600 °C showed signs of creep damage in the form of voids close to the fracture surface. In addition, the amount of low angle grain boundaries seems to decrease with the increase in temperature even though the inelastic strain amplitude was increased. The study indicates that a significant amount of the inelastic strain comes from creep strain as opposed of being all plastic strain, which need to be taken into consideration when constructing a life prediction model.

  • Karlsson, Ola
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion.
    It’s unbelievable, feels like you’re diving: Potential benefits of Virtual Reality for  documentation and analysis in underwater archaeology2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    This study examined questions around the scientific validity of using digital 3D models in underwater archaeology and the potential benefits of using virtual reality (VR) as a way of working with said models for documentation and analysis. A workshop with underwater archaeologists at the Swedish National Maritime and Transport Museums was conducted and the results indicate that depending on the research question being examined, there can indeed be validity in using digital 3D models, even if they are at a somewhat lower resolution. The results furthermore indicate that VR might give a better spatial understanding and overview of a site and provide a more familiar and intuitive interface for the archaeologists when working with the digital models. Several design openings were also identified and design suggestions for features in a potential VR tool were created.

  • Erlandsson, Daniel
    Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Matematiska institutionen.
    Ett undersökande arbetssätt med GeoGebra som verktyg för gymnasieelevers lärande av andragradsfunktioner: En designstudie2019Självständigt arbete på avancerad nivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Undersökningar har visat att ett problem elever har med andragradsfunktioner är att de har svårt att använda begreppet för att beskriva samband mellan variabler (Grønmo & Rosén, 1997). Detta i samband med andra problem kring arbetsmomentet leder till designstudiens syfte, vilket är att utveckla undervisningsmomentet som behandlar andragradsfunktioner och relaterade begrepp kopplade till kursplanen för Matematik 2c.

    Arbetsmetoden är ett undersökande arbetssätt. Verktyget som kommer att användas är GeoGebra. Syftet uppnås genom att data samlas in från elevsvar av arbetsuppgifter och enkätfrågor och den ordinarie lärarens observationer för att få information om vad som behöver re-designas för att undervisningsmomentet ska utvecklas.

    Designstudiens förslag av re-design för undervisningsmomentet är ge elever mer tid till att genomföra lektionens utvalda uppgifter och att undervisande lärare ska ha genomgång på de moment kring arbetsområdet som eleverna hade problem med. På så vis ges möjligheten för eleverna att få feedbackpå sitt arbete. De områden kring andragradsfunktioner som eleverna hade problem med var att: tyda en konstants värde om värdet är 0 eller 1, förstå konstanten 𝑎:s påverkan på parabeln, förstå begreppet nollställen samt att de blandar ihop funktionsvärden med punkter.

    En implikation för lärarrollen är att GeoGebra med dess synkroniserade vyer är ett lämpligt verktyg att använda då elever arbetar på ett undersökande sätt. Arbetssättet är särskilt lämpat för arbetsmomentet om räta linjens ekvation.

  • Jackson, Marcus
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system.
    Design of a mechatronic locking system in a rotating gear shifter: How a knowledge-intensive approach can be utilized in a product development project2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Gear shifters are currently undergoing a shift of technology forcing companies within the industry to develop new concepts and new designs. An example of this is Kongsberg Automotive that is developing one new innovative design; a rotating gear shifter. An important part of the rotating gear shifter is the locking system that control whenever rotation (shifting of gear) should be possible.

    The purpose and objective of this thesis is to show how the design of a mechatronic locking system can be implemented in the rotating gear shifter being developed by Kongsberg Automotive to fulfill the desired function (locking the rotating gear shifter), as well as optimizing it with regards to size, cost and energy consumption. The thesis is investigating how a knowledge-intensive approach can be adopted in order to deliberately and systematically build understanding of the basic principles involved in the operation of the new technology.

    The thesis presents six different design concepts that has been studied and, based on different design aspects, they have been compared to each other. The design concept that is deemed the most suitable to the application is a locking system based on a magnetic circuit.

    The physics of the magnetic circuit has been studied and a mathematical model of the system has been derived that identifies the design parameters that affect the size, cost and energy consumption. Simulations and experiments has been performed to compare how well the theory correlate to reality.

    A mathematical model is presented which has been derived from conventional physics. The thesis also presents simulations which has been performed using state-of-the-art software. Finally, results from experiments are presented which have been conducted on prototypes of the system. All results show the same behaviour which is taken as a verification and validation of the mathematical model, motivating its continued use in further design efforts. A knowledge-intensive approach can thus be used in the development of new designs.

  • Nordström, Jan
    et al.
    Linköpings universitet, Matematiska institutionen, Beräkningsmatematik. Linköpings universitet, Tekniska fakulteten.
    Ruggiu, Andrea Alessandro
    Linköpings universitet, Matematiska institutionen, Matematisk statistik. Linköpings universitet, Tekniska fakulteten.
    Eigenvalue analysis for summation-by-parts finite difference time discretizations2020Ingår i: SIAM Journal on Numerical Analysis, ISSN 0036-1429, E-ISSN 1095-7170, Vol. 58, nr 2, s. 907-928Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Diagonal norm finite difference based time integration methods in summation-by-parts form are investigated. The second, fourth, and sixth order accurate discretizations are proven to have eigenvalues with strictly positive real parts. This leads to provably invertible fully discrete approximations of initial boundary value problems. Our findings also allow us to conclude that the Runge--Kutta methods based on second, fourth, and sixth order summation-by-parts finite difference time discretizations automatically satisfy previously unreported stability properties. The procedure outlined in this article can be extended to even higher order summation-by-parts approximations with repeating stencil.

  • Hooijsma, Marianne
    et al.
    University of Groningen, Groningen, the Netherlands.
    Huitsing, Gijs
    University of Groningen, Groningen, the Netherlands.
    Kisfalusi, Dorottya
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Institutet för analytisk sociologi, IAS. Linköpings universitet, Filosofiska fakulteten.
    Dijkstra, Jan Kornelis
    University of Groningen, Groningen, the Netherlands.
    Flache, Adreas
    University of Groningen, Groningen, the Netherlands.
    Veenstra, René
    University of Groningen, Groningen, the Netherlands.
    Multidimensional similarity in multiplex networks: friendships between same- and cross-gender bullies and same- and cross-gender victims2020Ingår i: Network Science, ISSN 2050-1242, Vol. 8, nr 1, s. 79-96Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Similar peers are more likely to become friends, but it remains unclear how the combination of multiple characteristics, known as multidimensional similarity, influences friendships. This study aimed to investigate whether similarity in gender (attribute) and bullying or victimization (network position) contributes to friendships. The school-level networks of friendships and victim-bully relationships in 17 Dutch elementary schools (2,130 students) were examined using multiplex longitudinal social network models (RSiena). The results showed that friendships were more likely to occur between same-gender peers and between bullies sharing their targets of victimization. Multidimensional similarity (similarities in gender as well as bullying) increased the likelihood of friendships for same-gender bullies targeting the same victims, but not for same-gender victims sharing bullies. The findings underline the importance of unraveling the interplay between different dimensions of similarity for children’s relationships and surpass unidimensional similarity based on single attributes.

  • Disputation: 2020-04-23 13:15 Ada Lovelace, B-Building, LinköpingBeställ onlineKöp publikationen >>
    Roy, Biman
    Linköpings universitet, Institutionen för datavetenskap, Programvara och system. Linköpings universitet, Tekniska fakulteten.
    Applications of Partial Polymorphisms in (Fine-Grained) Complexity of Constraint Satisfaction Problems2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In this thesis we study the worst-case complexity ofconstraint satisfaction problems and some of its variants. We use methods from universal algebra: in particular, algebras of total functions and partial functions that are respectively known as clones and strong partial clones. The constraint satisfactionproblem parameterized by a set of relations Γ (CSP(Γ)) is the following problem: given a set of variables restricted by a set of constraints based on the relations Γ, is there an assignment to thevariables that satisfies all constraints? We refer to the set Γ as aconstraint language. The inverse CSPproblem over Γ (Inv-CSP(Γ)) asks the opposite: given a relation R, does there exist a CSP(Γ) instance with R as its set of models? When Γ is a Boolean language, then we use the term SAT(Γ) instead of CSP(Γ) and Inv-SAT(Γ) instead of Inv-CSP(Γ).

    Fine-grained complexity is an approach in which we zoom inside a complexity class and classify theproblems in it based on their worst-case time complexities. We start by investigating the fine-grained complexity of NP-complete CSP(Γ) problems. An NP-complete CSP(Γ) problem is said to be easier than an NP-complete CSP(∆) problem if the worst-case time complexity of CSP(Γ) is not higher thanthe worst-case time complexity of CSP(∆). We first analyze the NP-complete SAT problems that are easier than monotone 1-in-3-SAT (which can be represented by SAT(R) for a certain relation R), and find out that there exists a continuum of such problems. For this, we use the connection between constraint languages and strong partial clones and exploit the fact that CSP(Γ) is easier than CSP(∆) when the strong partial clone corresponding to  Γ contains the strong partial clone of ∆. An NP-complete CSP(Γ) problem is said to be the easiest with respect to a variable domain D if it is easier than any other NP-complete CSP(∆) problem of that domain. We show that for every finite domain there exists an easiest NP-complete problem for the ultraconservative CSP(Γ) problems. An ultraconservative CSP(Γ) is a special class of CSP problems where the constraint language containsall unary relations. We additionally show that no NP-complete CSP(Γ) problem can be solved insub-exponential time (i.e. in2^o(n) time where n is the number of variables) given that theexponentialtime hypothesisis true.

    Moving to classical complexity, we show that for any Boolean constraint language Γ, Inv-SAT(Γ) is either in P or it is coNP-complete. This is a generalization of an earlier dichotomy result, which was only known to be true for ultraconservative constraint languages. We show that Inv-SAT(Γ) is coNP-complete if and only if the clone corresponding to Γ contains essentially unary functions only. For arbitrary finite domains our results are not conclusive, but we manage to prove that theinversek-coloring problem is coNP-complete for each k>2. We exploit weak bases to prove many of theseresults. A weak base of a clone C is a constraint language that corresponds to the largest strong partia clone that contains C. It is known that for many decision problems X(Γ) that are parameterized bya constraint language Γ(such as Inv-SAT), there are strong connections between the complexity of X(Γ) and weak bases. This fact can be exploited to achieve general complexity results. The Boolean domain is well-suited for this approach since we have a fairly good understanding of Boolean weak bases. In the final result of this thesis, we investigate the relationships between the weak bases in the Boolean domain based on their strong partial clones and completely classify them according to the setinclusion. To avoid a tedious case analysis, we introduce a technique that allows us to discard a largenumber of cases from further investigation.

    Delarbeten
    1. A Preliminary Investigation of Satisfiability Problems NotHarder than 1-in-3-SAT
    Öppna denna publikation i ny flik eller fönster >>A Preliminary Investigation of Satisfiability Problems NotHarder than 1-in-3-SAT
    2016 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Nationell ämneskategori
    Datavetenskap (datalogi)
    Identifikatorer
    urn:nbn:se:liu:diva-164152 (URN)
    Konferens
    Proceedings of the 41st International Symposium on Mathematical Foundations of Computer Science (MFCS-2016)
    Tillgänglig från: 2020-03-07 Skapad: 2020-03-07 Senast uppdaterad: 2020-03-07
    2. On the Interval of Boolean Strong Partial ClonesContaining Only Projections as Total Operations
    Öppna denna publikation i ny flik eller fönster >>On the Interval of Boolean Strong Partial ClonesContaining Only Projections as Total Operations
    2017 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Nationell ämneskategori
    Datavetenskap (datalogi)
    Identifikatorer
    urn:nbn:se:liu:diva-164153 (URN)
    Konferens
    47th International Symposium on Multiple-Valued Logic (ISMVL-2017)
    Tillgänglig från: 2020-03-07 Skapad: 2020-03-07 Senast uppdaterad: 2020-03-07
    3. Time Complexity of Constraint Satisfaction via Universal Algebra
    Öppna denna publikation i ny flik eller fönster >>Time Complexity of Constraint Satisfaction via Universal Algebra
    2017 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Nationell ämneskategori
    Datavetenskap (datalogi)
    Identifikatorer
    urn:nbn:se:liu:diva-164154 (URN)
    Konferens
    42nd International Symposium on Mathematical Foundations of Computer Science (MFCS-2017)
    Tillgänglig från: 2020-03-07 Skapad: 2020-03-07 Senast uppdaterad: 2020-03-07
    4. A Dichotomy Theorem for the Inverse Satisfiability Problem
    Öppna denna publikation i ny flik eller fönster >>A Dichotomy Theorem for the Inverse Satisfiability Problem
    2018 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Nationell ämneskategori
    Datavetenskap (datalogi)
    Identifikatorer
    urn:nbn:se:liu:diva-164155 (URN)
    Konferens
    37th IARCS Annual Conference on Foundations of Software Technology and Theoretical Computer Science (FSTTCS-2017)
    Tillgänglig från: 2020-03-07 Skapad: 2020-03-07 Senast uppdaterad: 2020-03-07
    5. The Inclusion Structure of Boolean Weak Bases
    Öppna denna publikation i ny flik eller fönster >>The Inclusion Structure of Boolean Weak Bases
    2019 (Engelska)Ingår i: 2019 IEEE 49TH INTERNATIONAL SYMPOSIUM ON MULTIPLE-VALUED LOGIC (ISMVL), IEEE , 2019, s. 31-36Konferensbidrag, Publicerat paper (Refereegranskat)
    Abstract [en]

    Strong partial clones are composition closed sets of partial operations containing all partial projections, characterizable as partial polymorphisms of sets of relations Gamma (pPol(Gamma)). If C is a clone it is known that the set of all strong partial clones whose total component equals C, has a greatest element pPol(Gamma(w)), where Gamma(w) is called a weak base. Weak bases have seen applications in computer science due to their usefulness for proving complexity classifications for constraint satisfaction related problems. In this paper we completely describe the inclusion structure between pPol(Gamma(w)), pPol(Delta(w)) for all Boolean weak bases Gamma(w), and Delta(w.)

    Ort, förlag, år, upplaga, sidor
    IEEE, 2019
    Serie
    International Symposium on Multiple-Valued Logic, ISSN 0195-623X
    Nationell ämneskategori
    Datavetenskap (datalogi)
    Identifikatorer
    urn:nbn:se:liu:diva-160634 (URN)10.1109/ISMVL.2019.00014 (DOI)000484992100006 ()978-1-7281-0092-0 (ISBN)
    Konferens
    49th IEEE International Symposium on Multiple-Valued Logic (ISMVL)
    Tillgänglig från: 2019-10-11 Skapad: 2019-10-11 Senast uppdaterad: 2020-03-07
  • Muhrman, Karolina (Redaktör)
    Linköpings universitet, Institutionen för beteendevetenskap och lärande, Pedagogik och vuxnas lärande. Linköpings universitet, Utbildningsvetenskap.
    Ämnesdidaktik vid Linköpings universitet2020Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Denna skrift ger en översikt av de ämnesdidaktiska miljöerna vid Linköpings universitet. Var och en av de ämnesdidaktiska miljöerna presenteras i ett kapitel där ämnets historia och utveckling beskrivs, hur den nuvarande forskningsfronten ser ut och var Linköpings universitet befinner sig i denna. Författarna ger exempel på pågående och genomförda forskningsprojekt samt andra aktiviteter som sker i de ämnesdidaktiska miljöerna, till exempel seminarier. De beskriver också vad det sker för samverkan och samarbeten med andra universitet, skolor, företag eller myndigheter. I varje kapitel finns kontaktuppgifter till företrädare för respektive ämnesdidaktisk miljö.

    Syftet med skriften är att ge en översiktsbild av vad ämnesdidaktik kan innebära samt den forskning och de aktiviteter som sker inom ämnesdidaktik på LiU. Skriften vänder sig både internt till medarbetare på LiU och externt till skolhuvudmän, skolledare, lärare, myndigheter osv. Genom att presentera LiU:s ämnesdidaktiska verksamheter kan vi öppna upp för samarbeten såväl internt som externt, för att utveckla den ämnesdidaktiska forskningen vidare, eller för att ge ämnesdidaktiskt stöd i olika sammanhang.

  • Axelsson, Bodil
    Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Institutionen för kultur och samhälle, Avdelningen för kultur, samhälle, form och medier.
    ACSIS annual report 20182018Rapport (Övrigt vetenskapligt)
  • Axelsson, Bodil
    Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Institutionen för kultur och samhälle, Avdelningen för kultur, samhälle, form och medier.
    ACSIS Annual Report 20172017Rapport (Övrigt vetenskapligt)
  • Axelsson, Bodil
    Linköpings universitet, Filosofiska fakulteten. Linköpings universitet, Institutionen för kultur och samhälle, Avdelningen för kultur, samhälle, form och medier.
    ACSIS annual report 20162016Rapport (Övrigt vetenskapligt)
  • Salomonsson Olls, Anna
    Linköpings universitet, Institutionen för beteendevetenskap och lärande. Linköpings universitet, Utbildningsvetenskap.
    Specialpedagogisk verksamhet: Möjlighet eller hinder för lärande?2008Självständigt arbete på avancerad nivå (masterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Detta arbete är en deskriptiv studie av specialpedagogers och speciallärares uppfattningar om specialpedagogisk verksamhet och deras egen roll och uppdrag med koppling till detta. Med utgångspunkt från arbetets syfte och frågeställningar formulerades enkätfrågor som besvarades av nitton specialpedagoger och speciallärare på olika skolor i en kommun. Frågorna handlade om på vilka/vilket sätt specialpedagoger och speciallärare beskriver och tolkar olika specialpedagogiska begrepp samt vilka möjligheter och hinder de anger att denna form av verksamhet kan ha för barns lärande. Resultatet visar att specialpedagogerna och speciallärarna främst ser stora möjligheter med specialpedagogisk verksamhet men också en del hinder. Möjligheterna handlar om att kunna erbjuda elever i behov av särskilt stöd samma möjlighet till lärande och utveckling som alla elever genom alternativa metoder, anpassad miljö, läromedel och hjälpmedel. Hindren som presenteras är brist på resurser, tid och möjligheter till samarbete, samverkan och samsyn. Att eleverna genom arbetssättet särskiljs, mister sin klasstillhörighet och det sociala samspelet samt betraktas och upplever sig själv som avvikande är andra viktiga faktorer.

  • Olls, Anna
    Linköpings universitet, Institutionen för tematisk utbildning och forskning. Linköpings universitet, Filosofiska fakulteten.
    Att undervisa och bedöma elever i mångkulturella klasser - problem eller möjligheter?: En studie om lärares sätt att anpassa sin verksamhet i mångkulturella klasser.2000Självständigt arbete på grundnivå (kandidatexamen)Studentuppsats (Examensarbete)
    Abstract [sv]

    Detta arbete är ett resultat av en deskriptiv undersökning om lärares arbete i mångkulturell skola. Med utgångspunkt från arbetets syften och problemformulering formulerades enkätfrågor som besvarades av 29 lärare på tre skolor. Frågorna handlar främst om på vilka/vilket sätt lärare använder ett interkulturellt arbetssätt i undervisning och bedömning samt vilka problem och möjligheter verksamheten kan innebära. Resultatet visar att lärarna är väl medvetna om vad ett interkulturellt arbetssätt innebär. Samtliga lärare uppger att de i sin undervisning och bedömning av elever med annan bakgrund i något avseende anpassar verksamheten efter behoven även om metoderna varierar från person till person. Lärarna är överens om att arbetssättet innebär såväl problem som möjligheter.

  • Disputation: 2020-04-24 10:15 ACAS, A-Building, LinköpingBeställ onlineKöp publikationen >>
    Johansson, Henrik
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Logistik- och kvalitetsutveckling. Linköpings universitet, Tekniska fakulteten.
    Customer Benefits in City Logistics: Towards Viable Urban Consolidation Centres2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Urban Consolidation Centre (UCC) is a city logistics initiative that has the potential to increase the efficiency of urban freight delivery systems while reducing negative environmental and social effects caused by freight vehicles. One important issue that have hindered longevity of this initiative is its viability, both the financial viability and acceptance from affected stakeholders (also called UCC customers). The UCC customers in focus in this thesis are receivers of goods and municipalities. To satisfy both types of stakeholders, their requests and, in particular, the benefits they can gain from using UCCs need to be studied. The types of benefits to be given priority differ between the stakeholders, where municipalities strive towards more societal benefits, and the main goals of receivers are an increase in efficiency and financial sustainability. In response, the purpose of this thesis is to deepen the understanding of benefits for customers of UCCs, with a particular focus on customer needs and benefits that UCCs can provide.

    This thesis consists of five appended papers, each of which uses a different methodology. The methodologies applied in the papers include a multiple interview study of five UCCs, a surveybased interview study of retail stores, and a case study of an operating UCC. Regarding customer needs, this thesis takes the customer perspective, in order to identify needs that UCCs can meet. The results presented in this thesis also highlight the importance for UCCs to give priority to meeting customer needs that stem from some type of problem. Regarding benefits that UCCs can provide, the thesis suggests how different types of benefits can be distinguished. This can give guidance to UCC operators regarding which benefits should be given priority in communication with UCC customers. However, the results highlight that it is also important to understand the situation of the customer to be able to communicate the most relevant benefits that UCCs can provide. Furthermore, the results illustrate different improvement areas that can affect the benefits for UCC customers. These identified areas are: improved understanding by both UCCs and its customers of each other’s operation, communication, developing a more holistic view for UCC customers, and developing new UCC services to match customer needs.

    The results provide a foundation for customer needs that UCCs can meet, and the benefits that UCCs can provide. This foundation can be important for UCC customers to gain a better understanding of what a UCC is and how it can affect their operation, something that this thesis contributes towards. It can also assist initiators of UCCs to determine which customer needs they should focus on. Lastly, the results and contribution also address the potential role of municipalities, and it is argued that their role should change from a more supportive role to that of a paying UCC customer. All of these aspects can increase the probability that a UCC, when established becomes viable.

    Delarbeten
    1. Urban consolidation centre - a literature review, categorisation, and a future research agenda
    Öppna denna publikation i ny flik eller fönster >>Urban consolidation centre - a literature review, categorisation, and a future research agenda
    2018 (Engelska)Ingår i: International Journal of Physical Distribution & Logistics Management, ISSN 0960-0035, E-ISSN 1758-664X, Vol. 48, nr 8, s. 745-764Artikel, forskningsöversikt (Refereegranskat) Published
    Abstract [en]

    Purpose Urban consolidation centre (UCC) is a popular initiative targeting the challenge of negative environmental and social impacts from freight transports in cities. Despite this, UCC often fails in practice, which indicates a knowledge gap. Furthermore, research within the field can be described as fragmented, transdisciplinary and fast growing. The purpose of this paper is to provide an overview of the field by describing dominant categories and themes within the area, identify gaps in order to propose a future research agenda, and provide insights into the needs of practitioners. Design/methodology/approach A systematic literature review (SLR) targeting journal articles based on UCCs has been constructed with a supplementary snowball approach. A content analysis was performed to categorise themes in the research on UCCs and to identify research gaps, both within and outside the categories identified. Findings Despite substantial research on UCC, very little research ends up in academic journals. In all, 56 articles address UCC. The most common topics were the role of stakeholders, design of distribution structures and transport resources, environmental and social consideration, and economic considerations. Much focus is directed towards finding optimal solutions and designs for potential initiatives with very little, if any, consideration to financial viability or the management of the UCC initiative. Research limitations/implications This research points out existing gaps in the literature and proposes a future research agenda with UCCs as the focus. For example, although environmental and social arguments are often applied to justify the implementation of UCCs, few studies measure or evaluate their impact. Another important research gap is the economical consideration, both how to generate revenue and how to consider economies of scale. Practical implications The practical contribution of most studies is directed towards municipalities. Few findings are presented in a way to support companies. Additionally, by bridging the gaps related to how stakeholders can collaborate and describe what is happening in a UCC, practitioners can use such information as guidelines. Originality/value The results provide a research agenda for the fragmented research targeting UCCs, supporting the viability of future initiatives.

    Ort, förlag, år, upplaga, sidor
    EMERALD GROUP PUBLISHING LTD, 2018
    Nyckelord
    Content analysis; City logistics; Urban freight; Urban consolidation centre; Structural literature review
    Nationell ämneskategori
    Företagsekonomi
    Identifikatorer
    urn:nbn:se:liu:diva-151808 (URN)10.1108/IJPDLM-01-2017-0050 (DOI)000444391000002 ()
    Anmärkning

    Funding Agencies|Swedish Energy Agency

    Tillgänglig från: 2018-10-04 Skapad: 2018-10-04 Senast uppdaterad: 2020-03-20
    2. Critical factors for viable business models for urban consolidation centres
    Öppna denna publikation i ny flik eller fönster >>Critical factors for viable business models for urban consolidation centres
    2017 (Engelska)Ingår i: Research in Transportation Economics, ISSN 0739-8859, E-ISSN 1875-7979, Vol. 64, s. 36-47Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Abstract Although urban consolidation centres (UCC) worldwide have improved urban freight distribution and reduced externalities, other UCC initiatives have not materialised due to problems such as for example, business model limitations. All the same, researchers have rarely described business model components relevant to city logistics. In response, the purpose of this article is to analyse critical factors for viable business models of city logistics initiatives involving UCCs. Following an extensive literature review and multiple-case study of five initiatives with UCCs, we identified seven critical factors of viable city logistics business models: the ability to scale up and down the UCC solution; an ability to continuously develop and adapt to a dynamic environment; the important entrepreneurial role of the initiator as well; the acknowledgment of society; ability to innovate new services; logistics and supply chain management competence; and the ability to take full advantage of advanced IT. All seven factors describe continuously redeveloped business models seeking to seize new and unexpected opportunities, yet also indicate that city logistics systems require local authorities and municipalities to act as initiators, enablers, and customers. The models also underscore differences between purely commercial and purely municipal city logistics initiatives.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2017
    Nyckelord
    Urban logistics, Business models, Critical factors, Urban consolidation centres
    Nationell ämneskategori
    Transportteknik och logistik
    Identifikatorer
    urn:nbn:se:liu:diva-144226 (URN)10.1016/j.retrec.2017.09.009 (DOI)
    Forskningsfinansiär
    VINNOVA
    Tillgänglig från: 2018-01-11 Skapad: 2018-01-11 Senast uppdaterad: 2020-03-20
    3. Urban consolidation centres: retail stores demands for UCC services
    Öppna denna publikation i ny flik eller fönster >>Urban consolidation centres: retail stores demands for UCC services
    2017 (Engelska)Ingår i: International Journal of Physical Distribution & Logistics Management, ISSN 0960-0035, E-ISSN 1758-664X, Vol. 47, nr 7, s. 646-662Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Purpose - Urban consolidation centres (UCCs) are often conceived to improve services in retail stores and potentially reduce costs. However, few studies have examined how retail stores perceive the services a UCC could provide. The purpose of this paper is to explore retail stores potential demands for different services that a UCC could provide in order to foster the development and implementation of UCC solutions aimed towards more economically feasible business models. Design/methodology/approach - Structured interviews were conducted with employees at 72 retail stores. Qualitative, as well as quantitative analyses, were conducted to identify the potential demands of the retail stores. Findings - The authors have provided arguments why retail stores might be interested in UCC services, and thereby potentially pay for them. Improved customer service to stores customers might not be a valid argument. The authors point to the cost aspect: stores expend resources that a UCC could provide in a more cost-efficient manner. Research limitations/implications - The findings contradict previous studies to some extent, as it indicates that a UCC may actually not enhance customer service in retail stores. Instead, the findings point to the importance of considering the potential advantages according to economies of scale that are facilitated by UCC services. Practical implications - Taking the perspective of the stores is important in order to identify arguments for why they should pay for the services provided by a UCC. Social implications - Financially viable UCC solutions are needed in order for the initiatives to be maintained and thereby provide a long-term decrease in the environmental and social footprints caused by urban freight. Originality/value - This study answers the call for research addressing retailers perspective in urban logistics, as it takes a demand-driven perspective of the development of UCC services. Furthermore, by highlighting services requested by retail stores, it can guide the financing of UCC initiatives, an aspect that has been lacking.

    Ort, förlag, år, upplaga, sidor
    EMERALD GROUP PUBLISHING LTD, 2017
    Nyckelord
    Customer service; Business model; Urban freight; City logistics; Receivers; Urban consolidation centre; Urban distribution
    Nationell ämneskategori
    Företagsekonomi
    Identifikatorer
    urn:nbn:se:liu:diva-140529 (URN)10.1108/IJPDLM-02-2017-0114 (DOI)000407286000005 ()
    Konferens
    Annual Nordic Logistics and SCM Researchers Conference (NOFOMA)
    Anmärkning

    Funding Agencies|VINNOVA; Swedens Innovation Agency

    Tillgänglig från: 2017-09-11 Skapad: 2017-09-11 Senast uppdaterad: 2020-03-20
    4. Designing a business model for redistribution of surplus food
    Öppna denna publikation i ny flik eller fönster >>Designing a business model for redistribution of surplus food
    2018 (Engelska)Konferensbidrag, Publicerat paper (Refereegranskat)
    Nationell ämneskategori
    Transportteknik och logistik
    Identifikatorer
    urn:nbn:se:liu:diva-148837 (URN)
    Konferens
    NoFoMa 2018, Kolding, Denmark, 13-15 June, 2018
    Forskningsfinansiär
    VINNOVA, 2017-03156
    Tillgänglig från: 2018-06-20 Skapad: 2018-06-20 Senast uppdaterad: 2020-03-20Bibliografiskt granskad
  • Brattström, Ann
    Linköpings universitet, Institutionen för beteendevetenskap och lärande.
    Nyanlända mellanstadieelever i behov av särskilt stöd i matematik: En intervjustudie om hur svenska skolor arbetar med särskilda åtgärder och vilka dilemman som stöts på2020Självständigt arbete på avancerad nivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    När nyanlända elever, som kommer till Sverige i åldern 9 till 12 år, har stora kunskapsluckor i matematikkunnandet blir det ett utmanande arbete för den svenska skolan att tillgodose dessa elevers behov av stöd. Syftet med denna studie är fördjupa kunskap om hur svensk skola arbetar med nyanlända mellanstadieelever som på grund av bristande grundläggande matematikkunskaper är i behov av särskilt stöd. Studiens teoretiska utgångspunkt är ett dilemmaperspektiv. Metoden i studien är av empirisk kvalitativ karaktär där det genomfördes intervjuer med specialpedagoger och lärare. Empirin analyserades genom en tematisk analys. Studien slutsatser är att specialpedagoger och lärare på de svenska skolorna anser att det är en funktionell organisatorisk insats att nyanlända mellanstadieelever elever börjar i en förberedelseklass. Det genomförs många olika särskilda organisatoriska åtgärder på svenska skolor för att tillgodose behoven som dessa elever med bristande grundläggande matematiska grundkunskaper har. De flesta pedagogerna menar dock att insatserna inte räcker till på deras skolor. Vad gäller arbetsformer är pedagogerna ense om att det är viktigt att bygga upp de matematiska kunskaperna, steg för steg, att använda ett språkutvecklande arbetssätt, att börja med laborativt material och att släppa matematikboken. Det som upplevs som de största dilemman är att eleverna ofta ska inhämta mycket matematikkunskap på kort tid samt att de nyanlända eleverna inte behärskar undervisningsspråket och är obekanta med den svenska kulturen. Framgångsfaktorer som pedagogerna upplever är: undervisning i en mindre grupp, en erfaren lågstadielärare som har undervisningen med eleverna och att eleverna är motiverade i arbetet med matematikämnet.

  • Magnuson, Martin
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Olovsson, Weine
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten.
    Ghafoor, Naureen
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Odén, Magnus
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten.
    Hultman, Lars
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Interface bonding of Zr1−xAlxN nanocomposites investigated by x-ray spectroscopies and first principles calculations2020Ingår i: Physical Review Research, E-ISSN 2643-1564, Vol. 2, nr 1Artikel, recension (Refereegranskat)
    Abstract [en]

    The electronic structure, chemical bonding, and interface component in ZrN-AlN nanocomposites formed byphase separation during thin film deposition of metastable Zr1−xAlxN (x = 0.0, 0.12, 0.26, 0.40) are investigatedby resonant inelastic x-ray scattering, x-ray emission, and x-ray absorption spectroscopy and compared to firstprinciples calculations including transitions between orbital angular momentum final states. The experimentalspectra are compared with different interface-slab model systems using first principles all-electron full-potentialcalculations where the core states are treated fully relativistically. As shown in this work, the bulk sensitivity andelement selectivity of x-ray spectroscopy enables one to probe the symmetry and orbital directions at interfacesbetween cubic and hexagonal crystals. We show how the electronic structure develops from local octahedralbond symmetry of cubic ZrN that distorts for increasing Al content into more complex bonding. This results inthree different kinds of bonding originating from semicoherent interfaces with segregated ZrN and lamellar AlNnanocrystalline precipitates. An increasing chemical shift and charge transfer between the elements takes placewith increasing Al content and affects the bond strength and increases resistivity.

  • David, Johansson
    Linköpings universitet, Institutionen för datavetenskap, Programvara och system.
    Building maintainable web applications using React: An evaluation of architectural patterns conducted on Canvas LMS2020Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Maintainability for web applications is increasingly important due to increasing demands for advanced functionality as well as a short time-to-market. Fixing errors, reusing functionality and adding new features efficiently are crucial for making the application profitable for the software organization as well as valuable for the end-user. Modern frameworks and libraries such as React assist web engineers in building sophisticated applications using high-quality solutions called architectural patterns. In this thesis architectural patterns have been evaluated by performing static code analysis using well-established metrics. The evaluation was conducted using a Design Science Research approach on the Learning Management System Canvas. The results showed large variations in maintainability depending on the architectural pattern used.

  • Disputation: 2020-04-17 10:15 K3 Önnesjösalen, Kåkenhus, NorrköpingBeställ onlineKöp publikationen >>
    Adam, Rania Elhadi
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik, elektroteknik och matematik. Linköpings universitet, Tekniska fakulteten.
    Synthesis and Characterization of Some Nanostructured Materials for Visible Light-driven Photo Processes2020Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Nanostructured materials for visible light driven photo-processes such as photodegradation of organic pollutants and photoelectrochemical (PEC) water oxidation for hydrogen production are very attractive because of the positive impact on the environment. Metal oxides-based nanostructures are widely used in these photoprocesses due to their unique properties. But single nanostructured metal oxide material might suffer from low efficiency and instability in aqueous solutions under visible light. These facts make it important to have an efficient and reliable nanocomposite for the photo-processes. The combination of different nanomaterials to form a composite configuration can produce a material with new properties. The new properties which are due to the synergetic effect, are a combination of the properties of all the counterparts of the nanocomposite. Zinc oxides (ZnO) have unique optical and electrical properties which grant it to be used in optoelectronics, sensors, solar cells, nanogenerators, and photocatalysis activities. Although ZnO absorbs visible light from the sun due to the deep level band, it mainly absorbs ultraviolet wavelengths which constitute a small portion of the whole solar spectrum range. Also, ZnO has a problem with the high recombination rate of the photogenerated electrons. These problems might reduce its applicability to the photo-process. Therefore, our aim is to develop and investigate different nanocomposites materials based on the ZnO nanostructures for the enhancement of photocatalysis processes using the visible solar light as a green source of energy. Two photo-processes were applied to examine the developed nanocomposites through photocatalysis: (1) the photodegradation of organic dyes, (2) PEC water splitting. In the first photo-process, we used the ZnO nanoparticles (NPs), Magnesium (Mg)-doped ZnO NPs, and plasmonic ZnO/graphene-based nanocomposite for the decomposition of some organic dyes that have been used in industries. For the second photo-process, ZnO photoelectrode composite with different silver-based semiconductors to enhance the performance of the ZnO photoelectrode was used for PEC reaction analysis to perform water splitting. The characterization and photocatalysis experiment results showed remarkable enhancement in the photocatalysis efficiency of the synthesized nanocomposites. The observed improved properties of the ZnO are due to the synergetic effects are caused by the addition of the other nanomaterials. Hence, the present thesis attends to the synthesis and characterization of some nanostructured materials composite with ZnO that are promising candidates for visible light-driven photo-processes.  

    Delarbeten
    1. Synthesis of ZnO nanoparticles by co-precipitation method for solar driven photodegradation of Congo red dye at different pH
    Öppna denna publikation i ny flik eller fönster >>Synthesis of ZnO nanoparticles by co-precipitation method for solar driven photodegradation of Congo red dye at different pH
    2018 (Engelska)Ingår i: PHOTONICS AND NANOSTRUCTURES-FUNDAMENTALS AND APPLICATIONS, ISSN 1569-4410, Vol. 32, s. 11-18Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Solar driven photocatalytic processes to remove organic pollutants from wastewater and other aqueous solutions is very important and useful due to its environmental benefits regarding sustainability aspect. In this article, we report a study on the use of bare zinc oxide (ZnO) nanoparticles (NPs) prepared by the chemical low temperature co-precipitation method and used as a catalyst to degrade the Congo red dye from aqueous solution using solar radiation. We performed the photocatalytic experiments for degradation of Congo red dye under solar radiation at different pH values. The results showed that the ZnO NPs are effective under solar radiation for degradation of Congo red dye. Even when the pH was varied down to 4 or raised to 10, the degradation was observed to be slightly improved. This result is due to the excess of radicals species, which enhance the photocatalytic process. In general, the observed degradation efficiency of the ZnO NPs is due to the deep level defects within the band gap that were introduced during the growth process of the ZnO NPs, which enhance the absorption wavelength band towards the visible light region. Recycling of the ZnO NPs for 3 successive runs have indicated the feasibility of reusing the NPs for several times. This implies that by using bare ZnO NPs an efficient approach for degradation of toxic waste can be achieved. Radical scavengers were used to evaluate the role of the radicals in the reaction mechanism.

    Ort, förlag, år, upplaga, sidor
    ELSEVIER SCIENCE BV, 2018
    Nyckelord
    ZnO nanoparticles; Point defects; Photocatalytic
    Nationell ämneskategori
    Atom- och molekylfysik och optik
    Identifikatorer
    urn:nbn:se:liu:diva-153525 (URN)10.1016/j.photonics.2018.08.005 (DOI)000451653700003 ()
    Anmärkning

    Funding Agencies|department of Science and Technology, Linkoping University, Sweden

    Tillgänglig från: 2018-12-20 Skapad: 2018-12-20 Senast uppdaterad: 2020-03-18
    2. Synthesis of Mg-doped ZnO NPs via a chemical low-temperature method and investigation of the efficient photocatalytic activity for the degradation of dyes under solar light
    Öppna denna publikation i ny flik eller fönster >>Synthesis of Mg-doped ZnO NPs via a chemical low-temperature method and investigation of the efficient photocatalytic activity for the degradation of dyes under solar light
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    2020 (Engelska)Ingår i: Solid State Sciences, ISSN 1293-2558, E-ISSN 1873-3085, Vol. 99, artikel-id 106053Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Doped semiconductors nanostructures (NSs) have shown great interest as a potential for green and efficient photocatalysis activities. Magnesium (Mg)-doped zinc oxide (ZnO) nanoparticles (NPs) has been synthesized by a one-step chemical low temperature (60 °C) co-precipitation method without further calcination and their photocatalytic performance for photodegradation of Methylene blue (MB) dye under the illumination of solar light is investigated. The crystal structure of the synthesized NPs is examined by X-ray diffraction (XRD). XRD data indicates a slight shift towards higher 2θ angle in Mg-doped samples as compared to the pure ZnO NPs which suggest the incorporation of Mg2+ into ZnO crystal lattice. X-ray photoelectron spectroscopy (XPS), UV–Vis spectrophotometer and cathodoluminescence (CL) spectroscopy, were used to study electronics, and optical properties, respectively. The XPS analysis confirms the substitution of the Zn2+ by the Mg2+ into the ZnO crystal lattice in agreement with the XRD data. The photocatalytic activities showed a significant enhancement of the Mg-doped ZnO NPs in comparison with pure ZnO NPs. Hole/radical scavengers were used to reveal the mechanism of the photodegradation. It was found that the addition of the Mg to the ZnO lattices increases the absorption of the hydroxyl ions at the surface of the NPs and hence acts as a trap site leading to decrease the electron-hole pair and consequently enhancing the photodegradation.

    Ort, förlag, år, upplaga, sidor
    Elsevier, 2020
    Nyckelord
    ZnO nanoparticles, Mg-doped ZnO NPs, Photocatalytic, Photodegradation, Methylene blue, Congo red
    Nationell ämneskategori
    Materialkemi
    Identifikatorer
    urn:nbn:se:liu:diva-164333 (URN)10.1016/j.solidstatesciences.2019.106053 (DOI)000516720100024 ()2-s2.0-85074706430 (Scopus ID)
    Tillgänglig från: 2020-03-18 Skapad: 2020-03-18 Senast uppdaterad: 2020-03-24Bibliografiskt granskad
    3. Graphene-based plasmonic nanocomposites for highly enhanced solar-driven photocatalytic activities
    Öppna denna publikation i ny flik eller fönster >>Graphene-based plasmonic nanocomposites for highly enhanced solar-driven photocatalytic activities
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    2019 (Engelska)Ingår i: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 9, nr 52, s. 30585-30598Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    High-efficiency photocatalysts are crucial for the removal of organic pollutants and environmental sustainability. In the present work, we report on a new low-temperature hydrothermal chemical method, assisted by ultrasonication, to synthesize disruptive plasmonic ZnO/graphene/Ag/AgI nanocomposites for solar-driven photocatalysis. The plasmonic nanocomposites were investigated by a wide range of characterization techniques, confirming successful formation of photocatalysts with excellent degradation efficiency. Using Congo red as a model dye molecule, our experimental results demonstrated a photocatalytic reactivity exceeding 90% efficiency after one hour simulated solar irradiation. The significantly enhanced degradation efficiency is attributed to improved electronic properties of the nanocomposites by hybridization of the graphene and to the addition of Ag/AgI which generates a strong surface plasmon resonance effect in the metallic silver further improving the photocatalytic activity and stability under solar irradiation. Scavenger experiments suggest that superoxide and hydroxyl radicals are responsible for the photodegradation of Congo red. Our findings are important for the fundamental understanding of the photocatalytic mechanism of ZnO/graphene/Ag/AgI nanocomposites and can lead to further development of novel efficient photocatalyst materials.

    Ort, förlag, år, upplaga, sidor
    Royal Meteorological Society, 2019
    Nationell ämneskategori
    Den kondenserade materiens fysik
    Identifikatorer
    urn:nbn:se:liu:diva-160568 (URN)10.1039/C9RA06273D (DOI)000487989300064 ()
    Anmärkning

    Funding agencies: Department of Science and Technology (ITN) at Campus Norrkoping, Linkoping University, Sweden; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation

    Tillgänglig från: 2019-09-30 Skapad: 2019-09-30 Senast uppdaterad: 2020-03-18Bibliografiskt granskad
    4. n–n ZnO–Ag2CrO4 heterojunction photoelectrodes with enhanced visible-light photoelectrochemical properties
    Öppna denna publikation i ny flik eller fönster >>n–n ZnO–Ag2CrO4 heterojunction photoelectrodes with enhanced visible-light photoelectrochemical properties
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    2019 (Engelska)Ingår i: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 9, nr 14, s. 7992-8001Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    In this study, ZnO nanorods (NRs) were hydrothermally grown on an Au-coated glass substrate at a relatively low temperature (90 °C), followed by the deposition of Ag2CrO4 particles via a successive ionic layer adsorption and reaction (SILAR) route. The content of the Ag2CrO4 particles on ZnO NRs was controlled by changing the number of SILAR cycles. The fabricated ZnO–Ag2CrO4 heterojunction photoelectrodes were subjected to morphological, structural, compositional, and optical property analyses; their photoelectrochemical (PEC) properties were investigated under simulated solar light illumination. The photocurrent responses confirmed that the ability of the ZnO–Ag2CrO4 heterojunction photoelectrodes to separate the photo-generated electron–hole pairs is stronger than that of bare ZnO NRs. Impressively, the maximum photocurrent density of about 2.51 mA cm−2 at 1.23 V (vs. Ag/AgCl) was measured for the prepared ZnO–Ag2CrO4 photoelectrode with 8 SILAR cycles (denoted as ZnO–Ag2CrO4-8), which exhibited about 3-fold photo-enhancement in the current density as compared to bare ZnO NRs (0.87 mA cm−2) under similar conditions. The improvement in photoactivity was attributed to the ideal band gap and high absorption coefficient of the Ag2CrO4 particles, which resulted in improved solar light absorption properties. Furthermore, an appropriate annealing treatment was proven to be an efficient process to increase the crystallinity of Ag2CrO4 particles deposited on ZnO NRs, which improved the charge transport characteristics of the ZnO–Ag2CrO4-8 photoelectrode annealed at 200 °C and increased the performance of the photoelectrode. The results achieved in the present work present new insights for designing n–n heterojunction photoelectrodes for efficient and cost-effective PEC applications and solar-to-fuel energ

    Ort, förlag, år, upplaga, sidor
    Royal Society of Chemistry, 2019
    Nationell ämneskategori
    Fysik
    Identifikatorer
    urn:nbn:se:liu:diva-155657 (URN)10.1039/C9RA00639G (DOI)000462646000051 ()2-s2.0-85062919263 (Scopus ID)
    Anmärkning

    Funding agencies: University of Mohaghegh Ardabili-Iran and Linkoping University-Sweden; AForsk [17-457

    Tillgänglig från: 2019-03-22 Skapad: 2019-03-22 Senast uppdaterad: 2020-03-18Bibliografiskt granskad
    5. ZnO/Ag/Ag2WO4 photo-electrodes with plasmonic behavior for enhanced photoelectrochemical water oxidation
    Öppna denna publikation i ny flik eller fönster >>ZnO/Ag/Ag2WO4 photo-electrodes with plasmonic behavior for enhanced photoelectrochemical water oxidation
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    2019 (Engelska)Ingår i: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 9, nr 15, s. 8271-8279Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Ag-based compounds are excellent co-catalyst that can enhance harvesting visible light and increase photo-generated charge carrier separation owing to its surface plasmon resonance (SPR) effect in photoelectrochemical (PEC) applications. However, the PEC performance of a ZnO/Ag/Ag2WO4 heterostructure with SPR behavior has not been fully studied so far. Here we report the preparation of a ZnO/Ag/Ag2WO4 photo-electrode with SPR behavior by a low temperature hydrothermal chemical growth method followed by a successive ionic layer adsorption and reaction (SILAR) method. The properties of the prepared samples were investigated by different characterization techniques, which confirm that Ag/Ag2WO4 was deposited on the ZnO NRs. The Ag2WO4/Ag/ZnO photo-electrode showed an enhancement in PEC performance compared to bare ZnO NRs. The observed enhancement is attributed to the red shift of the optical absorption spectrum of the Ag2WO4/Ag/ZnO to the visible region (>400 nm) and to the SPR effect of surface metallic silver (Ag0) particles from the Ag/Ag2WO4 that could generate electron–hole pairs under illumination of low energy visible sun light. Finally, we proposed the PEC mechanism of the Ag2WO4/Ag/ZnO photo-electrode with an energy band structure and possible electron–hole separation and transportation in the ZnO/Ag/Ag2WO4 heterostructure with SPR effect for water oxidation. ER

    Ort, förlag, år, upplaga, sidor
    Royal Society of Chemistry, 2019
    Nationell ämneskategori
    Fysik
    Identifikatorer
    urn:nbn:se:liu:diva-155655 (URN)10.1039/C8RA10141H (DOI)000461445300016 ()
    Tillgänglig från: 2019-03-22 Skapad: 2019-03-22 Senast uppdaterad: 2020-03-18Bibliografiskt granskad