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• Linköping University, Faculty of Medicine and Health Sciences.
Busk Winquist, Emma (Photographer)
Bäckman, Karin (Photographer)
Linköping University, Faculty of Medicine and Health Sciences.
Året som gått 2019: Prioriteringscentrums verksamhetsberättelse2019Report (Other academic)
• Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Plastic Surgery Unit, Suez Canal University, Egypt.
Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Plastic Surgery Unit, Suez Canal University, Egypt. Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Linköping University, Department of Health, Medicine and Caring Sciences, Division of Prevention, Rehabilitation and Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Linköping University, Department of Biomedical and Clinical Sciences, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery. Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Hand and Plastic Surgery.
Needle Fasciotomy or Collagenase Injection in the Treatment of Dupuytren’s Contracture: A Retrospective Study2020In: Plastic and Reconstructive Surgery – Global Open, E-ISSN 2169-7574, Vol. 8, no 1Article, review/survey (Refereed)

Background: Dupuytren’s contracture is common among older people in Sweden. Previous studies comparing the treatment with an injection of collagenase with percutaneous needle fasciotomy found no differences. Methods: We retrospectively compared the degree of improvement in the deficit in extension of the joints in 2 groups of patients who had been treated with collagenase (71 fingers) or needle fasciotomy (109 fingers) before and 1 year after treatment. We compared the improvement of the extension deficit among the metacarpophalangeal (MCP) and proximal interphalangeal joints before and after the intervention; additionally, the level of improvement was classified into 3 levels (mild = 0° to 29°; moderate = 30° to 60°; considerable = 61° and more). Results: The degree of improvement of extension in the MCP joints was 11° greater in the collagenase group (P = 0.001). The number of patients who had an improvement of >60° (considerable) in extension was greater in the collagenase group (P = 0.02). Conclusion: Collagenase was more effective than needle fasciotomy in treating extension deficits of the MCP joints in Dupuytren’s contracture in this retrospective analysis. Further prospective studies are required to confirm the finding.

• Public defence: 2020-03-05 10:15 ACAS, A-building, Linköping
Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
Borehole Thermal Energy Storage Systems for Storage of Industrial Excess Heat: Performance Evaluation and Modelling2020Licentiate thesis, comprehensive summary (Other academic)

Improving industrial energy efficiency is considered an important factor in reducing carbon dioxide emissions and counteract climate change. For many industrial companies in cold climates, heat generated at the site in summer will not be needed to fulfil the site heat demand during this time, and is thus removed to the outdoor air. Although a mismatch between heat generation and heat demand primarily being seasonal, a mismatch may also exist at times in the winter, e.g. during milder winter days or high production hours. If this excess heat instead of being sent to the outdoors was stored for later use when it is needed, purchased energy for the site could be decreased. One way to do this is by the use of a borehole thermal energy storage (BTES) system.

A BTES system stores energy directly in the ground by using an array of closely drilled boreholes through which a heat carrier, often water, is circulated. So far, BTES systems used for heating purposes have mainly been used for storage of solar thermal energy. The BTES system has then been part of smaller district solar heating systems to reduce the seasonal mismatch between incoming solar radiation and heat demand, thus increasing system solar fraction. For this application of BTES systems, energy for storage can be controlled by the sizing of the solar collector area. At an industrial site, however, the energy that can be stored will be limited to the excess heat at the site, and the possible presence of several time-varying processes generating heat at different temperatures gives options as to which processes to include in the heat recovery process and how to design the BTES system. Moreover, to determine the available heat for storage at an industrial site, individual measurements of the heat streams to be included are required. Thus, this must be made more site-specific as compared to that of the traditional usage of BTES systems where solar thermal energy is stored, in which case long-time historic solar radiation data to do this is readily accessible for most locations. Furthermore, for performance predictions of industrial BTES systems to be used for both seasonal and short-term storage of energy, models that can treat the short-term effects are needed, as traditional models for predicting BTES performance do not consider this.

Although large-scale BTES systems have been around since the 1970’s, little data is to be found in the literature on how design parameters such as borehole spacing and borehole depth affect storage performance, especially for industrial BTES applications. Most studies that can be found with regard to the designing of ground heat exchanger systems are for traditional ground source heat pumps, working at the natural temperature of the ground and being limited to only one or a few boreholes.

In this work, the performance of the first and largest industrial BTES system in Sweden was first presented and evaluated with regard to the storage’s first seven years in operation. The BTES system, which has been used for both long- and short-term storage of energy, was then modelled in the IDA ICE 4.8 environment with the aim to model actual storage performance. Finally, the model was used to conduct a parametric study on the BTES system, where e.g. the impact on storage performance from borehole spacing and characteristics of the storage supply flow at heat injection were investigated. From the performance evaluation it could be concluded that lower than estimated quantities and/or quality of the excess heat at the site, resulting in lower storage supply flow temperatures at heat injection, has hindered the storage from reaching temperatures necessary for significant amounts of energy to be extracted. Based on the repeating annual storage behavior seen for the last years of the evaluation period, a long-term annual heat extraction and ratio of energy extracted to energy injected of approximately 400 MWh/year and 20% respectively are likely.

For the comparison of predicted and measured storage performance, which considered a period of three years, predicted values for total injected and extracted energy deviated from measured values by less than 1 and 3% respectively, and predicted and measured values for injected and extracted energy followed the same pattern throughout the period. Furthermore, the mean relative difference for the storage temperatures was 4%. A time-step analysis confirmed that the intermittent heat injection and extraction, occurring at intervals down to half a day, had been captured in the three-year validation. This as predictions would become erroneous when the time step exceeded the time at which these changes in storage operation occur.

Main findings from the parametric study include that 1) for investigated supply flows at heat injection, a high temperature was more important than a high flow rate in order to achieve high annual heat extractions and that 2) annual heat extraction would rapidly reduce as the borehole spacing was decreased from the one yielding the highest annual heat extraction, whereas the reduction in annual heat extraction was quite slow when the spacing was increased from this point. Another conclusion that came from the performance evaluation and the parametric study, as a consequence of the Emmaboda storage being designed as a high-temperature BTES system, intended working temperatures being 40–55 °C, was that the possibility of designing the BTES system for low working temperatures should be considered in the designing of a BTES system. Lower storage operation temperatures allow for more energy to be injected and in turn for more energy to be extracted and reduces storage heat losses to the surroundings.

1. Performance evaluation of an industrial borehole thermal energy storage (BTES) project - Experiences from the first seven years of operation
Open this publication in new window or tab >>Performance evaluation of an industrial borehole thermal energy storage (BTES) project - Experiences from the first seven years of operation
2019 (English)In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 143, p. 1022-1034Article in journal (Refereed) Published
##### Abstract [en]

Borehole thermal energy storage (BTES) is a technology which allows for both seasonal and short-to-medium-term storage of thermal energy and which can be used for both heating and cooling. This makes BTES of special interest to many industries. However, post-implementation evaluations of largescale industrial BTES are scarce. The BTES at Xylems production plant in Emmaboda, Sweden is one of the worlds largest BTES systems for storage of industrial excess heat. In this paper, the BTES at Emmaboda was evaluated with respect to how it was integrated and how it has performed during its first seven years of operation. The BTES consists of 140 boreholes, 150 m deep, and heat for storage is mainly recovered from two high-temperature ovens and the foundry ventilation air. So far, the highest heat extraction and BTES efficiency (19%) took place in the storage systems sixth full year of operation, when roughly 2200 MWh and 400 MWh were injected into and extracted from the storage respectively. One main reason extraction is not higher is that the quantities and/or the quality of the excess heat for storage are lower than estimated, thus hindering the storage from reaching the necessary temperatures for heat extraction. (C) 2019 Elsevier Ltd. All rights reserved.

##### Place, publisher, year, edition, pages
PERGAMON-ELSEVIER SCIENCE LTD, 2019
##### Keywords
Borehole thermal energy storage; Industrial excess heat; BTES performance; Temperature distribution; Geothermal technology; Thermal conductivity
##### National Category
Energy Engineering
##### Identifiers
urn:nbn:se:liu:diva-160376 (URN)10.1016/j.renene.2019.05.020 (DOI)000482686100004 ()
##### Note

Funding Agencies|Swedish Energy Agency

Available from: 2019-09-23 Created: 2019-09-23 Last updated: 2020-02-20
2. Empirical Validation and Numerical Predictions of an Industrial Borehole Thermal Energy Storage System
Open this publication in new window or tab >>Empirical Validation and Numerical Predictions of an Industrial Borehole Thermal Energy Storage System
2019 (English)In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, no 12, article id 2263Article in journal (Refereed) Published
##### Abstract [en]

To generate performance predictions of borehole thermal energy storage (BTES) systems for both seasonal and short-term storage of industrial excess heat, e.g., from high to low production hours, models are needed that can handle the short-term effects. In this study, the first and largest industrial BTES in Sweden, applying intermittent heat injection and extraction down to half-day intervals, was modelled in the IDA ICE 4.8 environment and compared to three years of measured storage performance. The model was then used in a parametric study to investigate the change in performance of the storage from e.g., borehole spacing and storage supply flow characteristics at heat injection. For the three-year comparison, predicted and measured values for total injected and extracted energy differed by less than 1% and 3%, respectively and the mean relative difference for the storage temperatures was 4%, showing that the performance of large-scale BTES with intermittent heat injection and extraction can be predicted with high accuracy. At the actual temperature of the supply flow during heat injection, 40 degrees C, heat extraction would not exceed approximately 100 MWh/year for any investigated borehole spacing, 1-8 m. However, when the temperature of the supply flow was increased to 60-80 degrees C, 1400-3100 MWh/year, also dependent on the flow rate, could be extracted at the spacing yielding the highest heat extraction, which in all cases was 3-4 m.

MDPI, 2019
##### Keywords
borehole thermal energy storage; industrial excess heat; model validation; performance predictions; IDA ICE
##### National Category
Energy Engineering
##### Identifiers
urn:nbn:se:liu:diva-159071 (URN)10.3390/en12122263 (DOI)000473821400036 ()
##### Note

Funding Agencies|Swedish Energy Agency [40531-1]; Linkoping University

Available from: 2019-07-22 Created: 2019-07-22 Last updated: 2020-02-20
• Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Digitala verktyg – lust till lärande: En kvalitativ intervjustudie om lärares, speciallärares och specialpedagogers uppfattningar om användandet av digitala verktyg i matematikundervisningen2019Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

Samhället i stort liksom skolan påverkas av den snabba digitaliseringen. Den digitala tekniken skapar nya pedagogiska möjligheter och utmaningar. Digitaliseringen förändrar lärandet i skolan både för elever och personal, både hur vi samtalar och söker lärdom. Vi ser en lärarroll i förändring.

Syftet med studien är att undersöka vilka uppfattningar lärare, speciallärare och specialpedagoger på lågstadiet har kring digitala verktyg i matematik.

Vi har genomfört tio intervjuer med lärare, speciallärare och specialpedagoger. Resultatet visar att det finns både positiva aspekter som att de digitala verktygen underlättar för inkludering, att elevernas motivation ökar eller att det är lättare att åskådliggöra undervisningsstoff liksom negativa aspekter som att det gör eleverna mer isolerade, det blir mindre tid till gemensamma diskussioner och mer tid som får läggas på att lösa tekniska problem. Slutsatsen blir ändå att de digitala verktygen, beroende på hur de används, kan gynna interaktion med artefakten eller andra människor via olika nätverk eller diskussioner vilket är viktigt för lärandet enligt den sociokulturella teorin. Det handlar dock mycket om att läraren får en förändrad roll och att lärarna behöver få fortbildning kring hur de kan använda sig av verktygen på bästa sätt.

• Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
”Det är skönt när det är tyst”: En studie om några elevers upplevelser av att undervisas i en särskild undervisningsgrupp2018Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

Vi vill med denna studie bidra till det specialpedagogiska forskningsfältet för att öka förståelsen kring elevers upplevelser av att undervisas i en särskild undervisningsgrupp. Syftet med studien är att undersöka hur några elever upplever sin skolgång och sitt lärande i en särskild undervisningsgrupp.

Detta är en kvalitativ studie som utgår från ett barnperspektiv och en fenomenologisk forskningsansats. Vi har använt semistrukturerade frågor och intervjuat tio elever i två kommuners särskilda undervisningsgrupper.

Denna studie redogör för sociokulturellt och specialpedagogiska perspektiv. Genom dessa perspektiv tolkades det insamlade intervjumaterialet som först analyserades med den interpretativa fenomenologiska analysmetoden.

De elever vi har intervjuat berättar om sina upplevelser av att undervisas i en särskild undervisningsgrupp. Deras svar visar i stort att de är positiva till sin kunskapsutveckling. De uttrycker även att de känner en större arbetsro eftersom det är lugnare och tystare än i deras tidigare klasser. Den största framgångsfaktorn enligt eleverna är att den särskilda undervisningsgruppen är mycket mindre än en vanlig skolklass. De intervjuade eleverna återkommer i sina svar till betydelsen av den lilla gruppen och den lugnare arbetsmiljön.

• Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
En interventionsstudie om subtraktion inom talområdet 0-20 med fokus på CRA: Effekter av en strukturerad intensivundervisning på Tier 2 nivå för elever i årskurs 4 och 82020Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

Hur eleverna presterar inom matematik under de tidigare åren i skolan är en stark indikator på hur samma elever presterar i matematik under grundskolans senare del. Ett matematiskt flyt, att eleven kan göra effektiva beräkningar av grundläggande matematik genom att använda lämpliga metoder, är viktigt för att eleverna ska kunna tillgodogöra sig den åldersadekvatamatematiken. Syftet med vår studie är att se hur elever i årskurs 4 och 8 påverkas av explicitintensivundervisning under fem veckor med fokus på subtraktion inom talområdet 0-20, samt att undersöka effektskillnaden mellan de olika årskurserna. För att kunna besvara syftet har vi genomfört en kvasiexperimentell studie och metodansatsen är teoriprövande deduktiv. Innan interventionen startade gjorde alla elever i de båda årskurserna ett förtest som visade att många elever inom de båda årskurserna hade brister när det kom till den automatiserade kunskapen inom det aktuella området. Utifrån detta gjorde vi ett urval och eleverna med lägst resultat utifrån förtestet delades in i en interventionsgrupp och en kontrollgrupp. Eleverna i interventionsgruppen fick träna talkombinationer och effektiva strategier för subtraktion efter ett strukturerat schema, med ett strukturerat lektionsinnehåll som byggde på CRA. Resultatet i studien utgår från resultaten på förtest och eftertest vilka mätte antal korrekt utförda beräkningar på 3 minuter. Genom en faktoriell ANOVA har resultatet analyserats och det visar en statistisk signifikant effekt för interventionsgrupp kontra kontrollgrupp. Gällande effektskillnaden mellan årskursernas interventionsgrupper går det inte att skilja dem åt och säga att den ena har utvecklats mer än den andra. I diskussionen har vi huvudfokus på interventionsgruppen som helhet när vi diskuterar både vår metod och vårt resultat i relation till den tidigare forskningen.

• KTH Royal Institute of Technology, Sweden.
Linköping University, University Services. Nanyang Technological University, Singapore. Chalmers University of Technology, Sweden. Nanyang Technological University, Singapore. Umeå University, Sweden. Chalmers University of Technology, Sweden. National Institute of Education, Singapore. Linnaeus University, Sweden. Örebro University, Sweden. Karolinska Institutet, Sweden. KTH Royal Institute of Technology, Sweden. Umeå University, Sweden. Linköping University, Department of Mathematics, Optimization . Linköping University, Faculty of Science & Engineering. University of Borås, Sweden. Nanyang Technological University, Singapore. Nanyang Technological University, Singapore. Swedish Higher Education Authority, Sweden. Umeå University, Sweden. Royal Swedish Academy of Engineering Sciences, Sweden. Nanyang Technological University, Singapore. Nanyang Technological University, Singapore. Nanyang Technological University, Singapore. The Swedish Foundation for International Cooperation in Research and Higher Education (STINT), Sweden. Lund University, Sweden.
Linking Education and Research: A Roadmap for Higher Education Institutions at the Dawn of the Knowledge Society2019Other (Other academic)

In an era characterized by a move towards a “knowledge society”, universities are central in fostering “knowledgeability”, that is the reflexive understanding of knowledge in knowledge societies. The objective of “knowledgeability” can be met through creating a stronger link between education and research. Furthermore, overall student performance, for example in critical thinking and problem solving, can be improved if research-related activities are incorporated into the curriculum. The aim of this paper is to use international examples to discuss the research- education nexus from four different perspectives, namely context, policy, implementation and quality, with case studies from higher education institutions in Singapore and Sweden. We suggest that different integrative technologies can be used to enhance the links, but it will be essential to consider the inputs of training, service and support in using new technology. Interestingly, the act of evaluating the link between education and research will increase awareness of this linkage by stakeholders involved in both education and research. In turn the link can be strengthened, contributing to increased quality in both education and research.

• Linköping University, Department of Management and Engineering, Project Innovations and Entrepreneurship. Linköping University, Faculty of Science & Engineering.
FOG Innovation. Företagsekonomiska institutionen, Göteborgs universitet. Företagsekonomiska institutionen, Göteborgs universitet.
Samverkan i urbana innovationssystem: En studie av Göteborg med fokus på transport och mobilitet för en hållbar stad2020Report (Other academic)

Syftet med denna rapport är att skapa en ökad förståelse för samspelet mellan olika aktörer i ett urbant innovationssystem. Fokus ligger på att utforska 1) vilka förutsättningar, drivkrafter, utmaningar och möjligheter som upplevs med att samverka från olika aktörers perspektiv, och 2) på vilket sätt lokala, nationella eller transnationella policyer, strategier, investeringar och forsknings- och innovationsfinansiering till olika aktörer spelar roll.

Studien som presenteras fokuserar specifikt på innovationssystemet kopplat till transport och mobilitet, rådande teknikutveckling och stadens hållbara utveckling i Göteborg. Göteborg kan beskrivas som ett nav i en expansiv region med fokus på innovation där flera olika aktörer, bl.a. med stöd av Vinnova, har bedrivit projekt och initiativ för att öka innovationsförmågan genom samverkan mellan t.ex. näringsliv, akademi och offentlig sektor.

Rapporten syftar till att ge en sammanhållen kunskapsbild om vad som är viktigt för samverkan, konkurrenskraft och hållbarhet i ett urbant innovationssystem och beskriver hur nyckelaktörer upplever nuläget. Nedan sammanfattas studiens huvudsakliga innehåll och rekommendationer.

• Institut de Mathématiques de Toulouse, Université Toulouse III Paul Sabatier, Toulouse, France.
Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
Stable and Accurate Filtering Procedures2020In: Journal of Scientific Computing, ISSN 0885-7474, E-ISSN 1573-7691, Vol. 82, no 1, p. 1-21, article id 16Article in journal (Refereed)

High frequency errors are always present in numerical simulations since no difference stencil is accurate in the vicinity of the $$\pi$$π-mode. To remove the defective high wave number information from the solution, artificial dissipation operators or filter operators may be applied. Since stability is our main concern, we are interested in schemes on summation-by-parts (SBP) form with weak imposition of boundary conditions. Artificial dissipation operators preserving the accuracy and energy stability of SBP schemes are available. However, for filtering procedures it was recently shown that stability problems may occur, even for originally energy stable (in the absence of filtering) SBP based schemes. More precisely, it was shown that even the sharpest possible energy bound becomes very weak as the number of filtrations grow. This suggest that successful filtering include a delicate balance between the need to remove high frequency oscillations (filter often) and the need to avoid possible growth (filter seldom). We will discuss this problem and propose a remedy.

• Linköping University, Department of Management and Engineering, Energy Systems.
A Standardized Approach for Water Reduction Measures in Industrial Companies: Organizational Constraints and Effects on Economy and Environment2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

The access of water globally is becoming more strained, why the focus on industrial water use is increasing. The present study examined how industries should approach water efficiency projects, what organizational constraints that should be addressed, and what effects water saving measures have on economic costs, environmental impact and influence from water related risks.

The study has been conducted at Saab Group. Primary data for water supply amount and cost has been obtained from twelve sites for the year of 2018. Data from these sites has been used to estimate the water use for the other 43 sites included in this study. Interviews with employees across Saab´s organization and with external stakeholders have functioned as important sources of information, combined with investigations of internal company documents.

To facilitate for companies to structurally address water efficiency projects, the concept of the Deming Cycle is developed in this study. The steps included are necessary to address major identified organizational constraints which are lack of communication, lack of incentives for employees, and lack of economic incentives. Furthermore, with water often having energy embedded into it, a new Water Management Hierarchy is developed to include the interrelated aspects of energy supply and energy recovery. The potential for pipe leakages and the challenge to detect these are also identified. If the time from leak occurrence to repair in 2018 was eliminated, the total water supply in Arboga could have been reduced with 10100 m3 which corresponds to 35% of total supply to the site, respectively 35900 m3 and 42% in Björkborn.

In Tannefors, water saving measures are identified for a surface treatment process, a facility with testing equipment, and by utilization of groundwater. Not all water saving measures result in reduced annual operating costs, due to an increased energy demand. Furthermore, if neglecting the possibility of energy recovery when aiming for water use reduction, the results show that replacing a once-through cooling system using potable municipal water as a medium with a dry-cooling unit, can increase greenhouse gas emissions. In 2018, the simultaneously implementable water saving measures in Tannefors would have reduced the water supply with 40600 m3, which corresponds to 22% of the total supply to the site. The greenhouse gas emissions would simultaneously have been reduced with 0.4 tonnes CO2eq. If also addressing energy supply reduction and energy recovery, some measures achieves a reduction of over 35 tonnes CO2eq, which results in enhanced economic viability from reduced operating costs.

This study suggest that organizational constraints have to be addressed to successfully implement identified water saving measures. To allow economic motivation for all water saving measures in Tannefors, a payback period of over 7 years has to be applied, which can be lowered if the measure also reduces energy demand or increases energy recovery. In order to avoid sub-optimization of water saving measures, the current Water Management Hierarchy has to include the aspects of energy supply and energy recovery. If the aim is to reduce a corporation’s water use, the largest sites with heavy industrial processes should be addressed first. However, the potential impact from water related risks at smaller sites should not be neglected, in order to ensure safe operations and avoid increased costs in the company´s supply chain.

• Public defence: 2020-03-24 13:15 Alan Turing, E-building, Linköping
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
Latency-aware Resource Management at the Edge2020Licentiate thesis, monograph (Other academic)

The increasing diversity of connected devices leads to new application domains being envisioned. Some of these need ultra low latency or have privacy requirements that cannot be satisfied by the current cloud. By bringing resources closer to the end user, the recent edge computing paradigm aims to enable such applications.

One critical aspect to ensure the successful deployment of the edge computing paradigm is efficient resource management. Indeed, obtaining the needed resources is crucial for the applications using the edge, but the resource picture of this paradigm is complex. First, as opposed to the nearly infinite resources provided by the cloud, the edge devices have finite resources. Moreover, different resource types are required depending on the applications and the devices supplying those resources are very heterogeneous. This thesis studies several challenges towards enabling efficient resource management for edge computing.

The thesis begins by a review of the state-of-the-art research focusing on resource management in the edge computing context. A taxonomy is proposed for providing an overview of the current research and identify areas in need of further work.

One of the identified challenges is studying the resource supply organization in the case where a mix of mobile and stationary devices is used to provide the edge resources. The ORCH framework is proposed as a means to orchestrate this edge device mix. The evaluation performed in a simulator shows that this combination of devices enables higher quality of service for latency-critical tasks.

Another area is understanding the resource demand side. The thesis presents a study of the workload of a killer application for edge computing: mixed reality. The MR-Leo prototype is designed and used as a vehicle to understand the end-to-end latency, the throughput, and the characteristics of the workload for this type of application. A method for modeling the workload of an application is devised and applied to MR-Leo in order to obtain a synthetic workload exhibiting the same characteristics, which can be used in further studies.

• Linköping University, Department of Culture and Society, Centre for Local Government Studies. Linköping University, Faculty of Arts and Sciences.
Linköping University, Department of Culture and Society, Centre for Local Government Studies. Linköping University, Faculty of Arts and Sciences.
Kommunala markanvisningars betydelse för hållbar stadsplanering: En studie om kommuners klimatarbete i markanvisnings-tävlingar och effekterna av lagändringen om kommunala särkrav2019Report (Other academic)

I och med det kommunala planmonopolet har kommuner en central roll vid planering av ny bebyggelse. Med klimatfrågans ökade betydelse har kommuner därför använt sig av sitt planmonopol för att skapa hållbara stadsdelar, exempelvis genom att ställa skarpare krav i markanvisningstävlingar än rådande byggföreskrifter. För att minska byggkostnader och förenkla planprocessen infördes emellertid en lagändring år 2015 som ogiltigförklarar sådana särkrav vid markanvisningar. Boverkets byggregler (BBR) begränsar därmed den kommunala ambitionsnivån i nybyggnation. Syftet med detta examensarbete var därför att undersöka hur kommuner kan arbeta med hållbarhet i markanvisningar för att bidra till att uppnå kommunala klimatmål, samt hur potentialen för markanvisning som instrument har ändrats i och med lagändringen om kommunala särkrav. För att undersöka detta utfördes först en litteraturstudie vilken sedan låg till grund för en intervjustudie som omfattade fyra kommuner: Linköping, Norrköping, Växjö och Västerås. Resultatet från intervjustudien visade att lagändringen medfört att de studerade kommunernas användning av urvalskriterier i markanvisningsprospekt övergått från skarpa, detaljerade krav, till att be byggherren att beskriva sina hållbarhetsambitioner för projektet. Lagändringen verkar dessutom ha försvårat möjligheterna för kommunerna att kunna driva ett mer ambitiöst hållbarhetsarbete vid nybyggnation än kravnivåerna i BBR och det ansvaret har istället övergått mer till staten och byggherrarna. Resultatet visade dock att det fortfarande finns sätt för kommuner att uppmuntra till en högre ambitionsnivå än BBR. Kommuner kan använda byggherrars önskan att upprätthålla en god relation till kommunen genom att prioritera byggherrar som tidigare har byggt i enlighet med sitt bygglov. Denna möjlighet är som starkast i regioner med hög efterfrågan på bostäder och där det råder god konkurrens mellan byggherrar. Kommuner har också möjlighet att prioritera byggherrar som använder miljöcertifieringssystem. Kommuner kan i praktiken använda sig av särkrav i markanvisningsprocesser som rör marköverlåtelser även i fortsättningen, men med risken att byggherrar kan komma att ogiltigförklara särkraven. Denna risk finns däremot inte om kommuner ställer särkrav vid uppförande av byggnader för kommuners egen räkning.

• Linköping University, Department of Behavioural Sciences and Learning, Education, Teaching and Learning. Linköping University, Faculty of Educational Sciences.
Kombinationen av helhet och delar i subtraktion: En intervention i skriftlig subtraktion på nivå 3 i årskuserna 4 och 5 med Numicon och bildstöd2019Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

An experimental case study in the field of mathematics has been conducted in single case design where the individual is their own control group. Previous research indicates that individual intensive level 3 teaching according to the RTI model seems to lead to an increase in students' understanding of mathematics. The study's issue is that through CRA-based teaching, where the teacher guides the student from the concrete learning to the abstract, see if the students' understanding of solving subtraction tasks through set-up increases. In the teaching, the laboratory material Numicon was used together with image support for mathematical concepts. The result follows previous research by intervention that increased the students' ability to solve subtraction numbers through set-up.

• Public defence: 2020-03-02 10:15 Transformen, B-house, entrance 27, Linköping
Linköping University, Department of Electrical Engineering, Communication Systems. Linköping University, Faculty of Science & Engineering.
Analysis of Cellular and Cell-Free Massive MIMO with Rician Fading2020Licentiate thesis, comprehensive summary (Other academic)

The data traffic in cellular networks has grown at an exponential pace for decades. This trend will most probably continue in the future, driven by new innovative applications. One of the key enablers of future cellular networks is the massive MIMO technology. A massive MIMO base station is equipped with a massive number (e.g., a hundred) of individually steerable antennas, which can be effectively used to serve tens of user equipments simultaneously on the same time-frequency resource. It can provide a notable enhancement of both spectral efficiency and energy efficiency in comparison with conventional MIMO.

In the literature, the achievable spectral efficiencies of massive MIMO systems with a practical number of antennas have been rigorously characterized and optimized when the channels are subject to either spatially uncorrelated or correlated Rayleigh fading. Typically, in massive MIMO research, i.i.d. Rayleigh fading or less frequently free-space line-of-sight (LoS) channel models are assumed since they simplify the analysis. Massive MIMO technology is able to support both rich scattering and LoS scenarios. However, practical channels can consist of a combination of an LoS path and a correlated small-scale fading component caused by a finite number of scattering clusters that can be modeled by spatially correlated Rician fading. In the first part of this thesis, we consider a multi-cell scenario with spatially correlated Rician fading channels and derive closed-form achievable spectral efficiency expressions for different signal processing techniques.

Alternatively, a massive number of antennas can be spread over a large geographical area and this concept is called cell-free massive MIMO. In the canonical form of cell-free massive MIMO, the access points cooperate via a fronthaul network to spatially multiplex the users on the same time-frequency resource using network MIMO methods that only require locally obtained channel state information. Cellfree massive MIMO is a densely deployed system. Hence, the probability of having an LoS path between some access points and the users is quite high. In the second part of this thesis, we consider a practical scenario where the channels between the access points and the users are modeled with Rician fading.

1. Massive MIMO With Spatially Correlated Rician Fading Channels
Open this publication in new window or tab >>Massive MIMO With Spatially Correlated Rician Fading Channels
2019 (English)In: IEEE Transactions on Communications, ISSN 0090-6778, E-ISSN 1558-0857, Vol. 67, no 5, p. 3234-3250Article in journal (Refereed) Published
##### Abstract [en]

This paper considers multi-cell massive multiple-input multiple-output systems, where the channels are spatially correlated Rician fading. The channel model is composed of a deterministic line-of-sight path and a stochastic non-line-of-sight component describing a practical spatially correlated multipath environment. We derive the statistical properties of the minimum mean squared error (MMSE), element-wise MMSE, and least-square channel estimates for this model. Using these estimates for maximum ratio combining and precoding, rigorous closed-form uplink (UL) and downlink (DL) achievable spectral efficiency (SE) expressions are derived and analyzed. The asymptotic SE behavior, when using the different channel estimators, are also analyzed. The numerical results show that the SE is higher when using the MMSE estimator than that of the other estimators, and the performance gap increases with the number of antennas.

##### Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2019
##### Keywords
Massive MIMO; spatially correlated Rician fading; channel estimation; spectral efficiency
##### National Category
Signal Processing
##### Identifiers
urn:nbn:se:liu:diva-158364 (URN)10.1109/TCOMM.2019.2893221 (DOI)000468228900011 ()2-s2.0-85059952523 (Scopus ID)
##### Conference
19th IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
##### Note

Funding Agencies|ELLIIT; Swedish Research Council

Available from: 2019-07-02 Created: 2019-07-02 Last updated: 2020-02-18Bibliographically approved
2. Performance of Cell-Free Massive MIMO With Rician Fading and Phase Shifts
Open this publication in new window or tab >>Performance of Cell-Free Massive MIMO With Rician Fading and Phase Shifts
2019 (English)In: IEEE Transactions on Wireless Communications, ISSN 1536-1276, E-ISSN 1558-2248, Vol. 18, no 11, p. 5299-5315Article in journal (Refereed) Published
##### Abstract [en]

In this paper, we study the uplink (UL) and downlink (DL) spectral efficiency (SE) of a cell-free massive multiple-input-multiple-output (MIMO) system over Rician fading channels. The phase of the line-of-sight (LoS) path is modeled as a uniformly distributed random variable to take the phase-shifts due to mobility and phase noise into account. Considering the availability of prior information at the access points (APs), the phase-aware minimum mean square error (MMSE), non-aware linear MMSE (LMMSE), and least-square (LS) estimators are derived. The MMSE estimator requires perfectly estimated phase knowledge whereas the LMMSE and LS are derived without it. In the UL, a two-layer decoding method is investigated in order to mitigate both coherent and non-coherent interference. Closed-form UL SE expressions with phase-aware MMSE, LMMSE, and LS estimators are derived for maximum-ratio (MR) combining in the first layer and optimal large-scale fading decoding (LSFD) in the second layer. In the DL, two different transmission modes are studied: coherent and non-coherent. Closed-form DL SE expressions for both transmission modes with MR precoding are derived for the three estimators. Numerical results show that the LSFD improves the UL SE performance and coherent transmission mode performs much better than non-coherent transmission in the DL. Besides, the performance loss due to the lack of phase information depends on the pilot length and it is small when the pilot contamination is low.

##### Place, publisher, year, edition, pages
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2019
##### Keywords
Channel estimation; Fading channels; Rician channels; Coherence; Random variables; Decoding; Cell-free massive MIMO; Rician fading; phase shift; performance analysis
##### National Category
Telecommunications
##### Identifiers
urn:nbn:se:liu:diva-162767 (URN)10.1109/TWC.2019.2935434 (DOI)000496947800020 ()
##### Note

Funding Agencies|ELLIIT; Swedish Research CouncilSwedish Research Council; National Natural Science Foundation of ChinaNational Natural Science Foundation of China [61601020, U1834210]; Beijing Natural Science FoundationBeijing Natural Science Foundation [4182049, L171005]

Available from: 2019-12-17 Created: 2019-12-17 Last updated: 2020-02-18
• Linköping University, Department of Behavioural Sciences and Learning, Education and Sociology.
Linköping University, Department of Behavioural Sciences and Learning, Education and Sociology.
Inte dödstråkigt, inte askul utan mellanmjölk: en kvalitativ studie om normer och värderingar i Åtvidaberg2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

Syftet med denna studie är att söka utröna vilka normer och värderingar som finns i Åtvidaberg samt vilka påverkanskrafter detta har på den enskilda individen. Studien har en kvalitativ ansats och präglas företrädesvis av induktion men har även subtila inslag av deduktion. Det epistemologiska förfarandet är hermeneutik då det fokuserar på tolkning och förförståelse gällande upplevelsen av fenomenet. Datainsamlingen har skett genom elva semistrukturerade kvalitativa intervjuer. Av studien har det framkommit att Åtvidaberg präglas av normer och värderingar som kontinuitet, social kontroll, homogenitet och xenofobi. Frångår du dessa normer och värderingar riskerar du att bli sanktionerad, därmed är påverkanskraften relativt stark för att hållas inom det rätta ledet.

• Linköping University, Department of Behavioural Sciences and Learning.
Linköping University, Department of Behavioural Sciences and Learning.
Berättande inom historieämnet: möjligheter till utvecklande av elevers historiemedvetande i grundskolan2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis

Syftet med uppsatsen är att genom en strukturerad litteraturstudie undersöka hur berättande kan användas inom historieämnet. Vi har undersökt vilken roll berättande kan ha för att ge elever förståelse för historien och utveckla deras historiemedvetande. I vår analys kring berättande inom historieundervisningen finner vi att berättande kan vara ett användbart verktyg på flera sätt. Bland annat för att ge eleverna möjlighet att leva sig in i historien och identifiera sig med historiska karaktärer, vilket kan leda till utveckling av historiemedvetande.

• Public defence: 2020-02-27 13:15 Planck, Fysikhuset, entrance 57, Linköping
Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
Kähler-Poisson Algebras2020Doctoral thesis, comprehensive summary (Other academic)

In this thesis, we introduce Kähler-Poisson algebras and study their basic properties. The motivation comes from differential geometry, where one can show that the Riemannian geometry of an almost Kähler manifold can be formulated in terms of the Poisson algebra of smooth functions on the manifold. It turns out that one can identify an algebraic condition in the Poisson algebra (together with a metric) implying that most geometric objects can be given a purely algebraic formulation. This leads to the definition of a Kähler-Poisson algebra, which consists of a Poisson algebra and a metric fulfilling an algebraic condition. We show that every Kähler- Poisson algebra admits a unique Levi-Civita connection on its module of inner derivations and, furthermore, that the corresponding curvature operator has all the classical symmetries. Moreover, we present a construction procedure which allows one to associate a Kähler-Poisson algebra to a large class of Poisson algebras. From a more algebraic perspective, we introduce basic notions, such as morphisms and subalgebras, as well as direct sums and tensor products. Finally, we initiate a study of the moduli space of Kähler-Poisson algebras; i.e for a given Poisson algebra, one considers classes of metrics giving rise to non-isomorphic Kähler-Poisson algebras. As it turns out, even the simple case of a Poisson algebra generated by two variables gives rise to a nontrivial classification problem.

1. Kahler-Poisson algebras
Open this publication in new window or tab >>Kahler-Poisson algebras
2019 (English)In: Journal of Geometry and Physics, ISSN 0393-0440, E-ISSN 1879-1662, Vol. 136, p. 156-172Article in journal (Refereed) Published
##### Abstract [en]

We introduce Kahler-Poisson algebras as analogues of algebras of smooth functions on Kahler manifolds, and prove that they share several properties with their classical counterparts on an algebraic level. For instance, the module of inner derivations of a Kahler-Poisson algebra is a finitely generated projective module, and allows for a unique metric and torsion-free connection whose curvature enjoys all the classical symmetries. Moreover, starting from a large class of Poisson algebras, we show that every algebra has an associated Kahler-Poisson algebra constructed as a localization. At the end, detailed examples are provided in order to illustrate the novel concepts. (C) 2018 Elsevier B.V. All rights reserved.

##### Place, publisher, year, edition, pages
ELSEVIER SCIENCE BV, 2019
##### Keywords
Lie-Rinehart algebra; Kahler manifold; Levi-Civita connection; Curvature
##### National Category
Other Physics Topics
##### Identifiers
urn:nbn:se:liu:diva-154675 (URN)10.1016/j.geomphys.2018.11.001 (DOI)000456763300013 ()
##### Note

Funding Agencies|Swedish Research Council [621-2013-4538]

Available from: 2019-03-01 Created: 2019-03-01 Last updated: 2020-01-20
• Linköping University, Department of Computer and Information Science.
Supporting Resilient Behaviour in Simulation Studies: A study of how resilient behaviour can be enhanced in a crisis management exercise based on participants experiences2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

A major disruption in the payment system would be a considerable societal crisis and is studied by a project called Creating Collaborative Resilience Awareness, Analysis and Action for Finance, Food and Fuel Systems in INteractive Games (CCRAAAFFFTING), using serious gaming and simulation. This study examines the experiences of the participants in the crisis management exercises. The research questions of this study are as follows: “How do the participants of the simulation studies of CCRAAAFFFTING understand the games?” and “How can the simulation environment be developed in order to encourage the participants to improve monitoring strategies during the games?”.

The study uses thematic analysis of qualitative interviews of the participants supported by questionnaires. The questionnaires were conducted directly after the games, and telephone interviews were conducted after the exercise.

This study found the following main themes in the participants’ experiences of the games: the crisis, the society that is handling the crisis, the game’s relation to reality, the importance of the group, and the exercise’s ability to support the interpretation of what is simulated. Some consideration for the project to work further with are that the simulation needs to be centred, simplified and made more available to the participants. The division of roles could divide the monitoring of different actions affecting different parts of the society between the participants. Furthermore, a representation of the overall payment system, its actors and the groups, might support the participants in sharing and understanding the actors of the payment system, and the effects their actions have on them, as well as the participants’ ability to monitor the changes.

• Linköping University, Department of Computer and Information Science, Human-Centered systems.
Predicting Swedish News Article Popularity2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

In this work, 132,229 articles from a Swedish news publisher are used to explore news article popularity prediction. Linear-, k-Nearest Neighbor- and Support Vector Regression are evaluated using the two different metrics root mean squared error and R2. The problem is then relaxed into only attempting to rank the articles relative to each other. The prediction problem is also explored as a classification problem using the classes Low, Mid and High popularity. The classifiers evaluated are Naive Bayes and SVM using pre-defined features and using a Bag-of-words feature set. The results were analyzed to understand what information they can bring to the editors at the publisher and news agencies in general. The results clearly showed that the manually set metadata newsvalue had a large impact on article performance. A survey was done with editors to compare human prediction performance with the classifier performance. Although the SVM classifier performs with higher accuracy than the editors (59% vs 55%) the models are considered weak in their current state.

• Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems.
Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems.
Hydraulic pump efficiency test evaluation and improvement: Calculation, presentation and automation2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis

During this project the method and calculation for a hydraulic axial piston pump efficiency test has been evaluated. There are difficulties in how the maximum displacement of an axial piston pump is defined and this also affects the efficiency calculation of the test. After research about this, a document with improved structure, calculation and presentation of the test data has been developed.

Suggestions for further improving the test environment and automation of the efficiency test have been presented. To understand and experiment with the test environment, a simulation model has been developed. The first step towards automation would be to measure the drainage flow from the pump in an automated way. Therefore a flow meter that fits for this application has been recommended.

• Linköping University, Department of Physics, Chemistry and Biology, Nanoscale engineering. Linköping University, Faculty of Science & Engineering.
Linköping University, Department of Physics, Chemistry and Biology, Nanoscale engineering. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Nanoscale engineering. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Nanoscale engineering. Linköping University, Faculty of Science & Engineering.
Coalescence dynamics of 3D islands on weakly-interacting substrates2020In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 10, no 1, article id 2031Article in journal (Refereed)

We use kinetic Monte Carlo simulations and analytical modelling to study coalescence of three-dimensional (3D) nanoscale faceted silver island pairs on weakly-interacting fcc(111) substrates, with and without concurrent supply of mobile adatoms from the vapor phase. Our simulations show that for vapor flux arrival rates F < 1 monolayer/second (ML/s) coalescence manifests itself by one of the islands absorbing the other via sidewall facet migration. This process is mediated by nucleation and growth of two-dimensional (2D) layers on the island facets, while the supply of mobile atoms increases the nucleation probability and shortens the time required for coalescence completion. When F is increased above 1 ML/s, coalescence is predominantly governed by deposition from the vapor phase and the island pair reaches a compact shape via agglomeration. The crucial role of facets for the coalescence dynamics is further supported by a mean-field thermodynamic description of the nucleation energetics and kinetics. Our findings explain experimental results which show that two-dimensional film growth morphology on weakly-interacting substrates is promoted when the rate of island coalescence is suppressed. The present study also highlights that deviations of experimentally reported film morphological evolutions in weakly-interacting film/substrate systems from predictions based on the sintering and particle growth theories may be understood in light of the effect of deposition flux atoms on the energetics and kinetics of facet-layer nucleation during coalescence.

Tionde nationella prioriteringskonferensen 2019: En summering2019Report (Other academic)

Prioriteringskonferensen som arrangerades tillsammans med Region Stockholm på City Conference Centre Stockholm den 19–21 november bjöd på många presentationer, diskussioner och erfarenhetsutbyten. Första dagen var det förmöte med grundkurs i prioriteringskunskap och de två följande dagarna bjöds det på ett fullspäckat program med intressanta sessioner. Drygt 330 personer från hela landet kom för att uppdatera sig inom området.

Den nationella prioriteringskonferensen är en mötesplats för personer som arbetar med prioritering inom vård och omsorg på olika sätt och fokuserar bland annat på metoder och arbetssätt, etiska frågeställningar, organisering av prioriteringsprocesser, rollfördelning mellan aktörer och lämpliga beslutsunderlag. Konferensen äger rum vartannat år och nu var det den tionde gången som konferensen arrangerades. Temat för årets konferens var:”Vård efter behov – hur svårt ska det vara?”. Moderator på konferen­sen var Christina Kennedy, chefredaktör på Dagens Medicin.

• Public defence: 2020-02-28 13:00 K2, Kåkenhus, Norrköping
Linköping University, Department of Culture and Society, Division of Culture, Society, Design and Media. Linköping University, Faculty of Arts and Sciences.
"Chorus of the Saved": Constructing the Holocaust Survivor in Swedish Public Discourse, 1943-19662020Doctoral thesis, monograph (Other academic)

In this dissertation I examine how the Holocaust survivor has been constructed in Swedish public discourse during the 1940s, 1950s and 1960s. This is done using a Foucauldian-inspired genealogical method through which an eclectic collection of sources—newsreels, films, radio programs, television programs and newspaper articles—is analyzed. The theoretical underpinnings of this analysis are based on Ian Hacking’s concept of discourse where the classification of survivor ‘types’ has a direct bearing on the expressions possible for those who are classified, i.e. individuals with Holocaust experience. The overarching research question of the dissertation therefore asks: how did a Holocaust survivor ‘type’ develop in Sweden during the 1940s, 50s and 60s?  The main thrust of the argument presented in the dissertation is that the concepts of ‘silence’ and ‘excess’ have always disciplined the ways in which Holocaust survivors have been conceived of as both victims and witnesses in Swedish public discourse. The communication of Jewish suffering by survivor-witnesses has both been framed as a dangerous, destructive force which could instigate unnecessary conflict while it, at the same time, has been positioned as a remedy to collective forgetfulness as well as a solution to rising levels of xenophobia and antisemitism. How survivors have been constructed historically also demonstrates the flawed logic of a historical progressivism within which Holocaust memory is seen to steadily go from silence to interest/increased knowledge. What the research presented in this dissertation shows is that this process is not determined by historical progression but by the underlying problematization of Holocaust survivors’ utility.

• Linköping University, Department of Culture and Communication, Culture and Aesthetics. Linköping University, Faculty of Arts and Sciences.
A Disability Bioethics Reading of the FDA and EMA Evaluations on the Marketing Authorisation of Growth Hormone for Idiopathic Short Stature Children2020In: Health Care Analysis, ISSN 1065-3058, E-ISSN 1573-3394, p. 1-17Article in journal (Refereed)

The diagnosis of idiopathic short stature (ISS) refers to children who are considerably shorter than average without any identified medical reason. The US Food and Drug Administration (FDA) authorised marketing of recombinant human growth hormone (hGH) for ISS in 2003, while the European Medicines Agency (EMA) refused it in 2007. This paper examines the arguments for these decisions as detailed in selected FDA and EMA documents. It combines argumentative analysis with an approach to policy analysis called ‘What’s the problem represented to be’. It argues that the FDA presents its approval as an argument for equity of access to the treatment (given that hGH was already authorised for other indications), describing short stature as a potential disadvantage, and assuming that height normalisation is a clinically meaningful result. The EMA, instead, refuses marketing authorisation with an argument that there is an imbalance of risks and benefits, describing ISS as a healthy condition, and arguing that hGH should provide some psychosocial and/or quality of life benefits to children with ISS other than height gain. This paper then discusses how these arguments could be read through different models of disability, particularly through the medical model of disability and the relational, experiential, and cultural understandings of disability.

• Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Bråk, en betydelsefull utmaning i matematik: En kvantitativ studie i form av intervention inom bråk på gruppnivå, Tier 2 i matematik på introduktionsprogrammet2019Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

Studien har utgått från en modell, Respons to Intervention (RTI) och syftet har varit att bidra med kunskap om interventioner och att undersöka om en intervention, RTI på Tier 2nivå, i matematik inom området bråk genom explicit undervisning, laborativt material och digitalt läromedel (Nomp) har effekt på elever i svårigheter i matematik (årskurs 9) på introduktionsprogrammet. Urvalet av elever byggde på ett övergripande matematiktest som alla elever (n=40) i fyra olika matematikklasser genomfört vid samma tillfälle på introduktionsprogrammet på en gymnasieskola. För denna kvantitativa studie har både en experimentgrupp och en kontrollgrupp använts. 9 elever genomförde ett interventionsprogram gällande bråk, med fokus på begreppslig förmåga och procedurförmåga under tre veckor. Kontrollgruppen erhöll ingen interventionsinsats inom bråk utan deltog i den ordinarie matematikundervisningen om bråk.   Studiens resultat bygger på vår insamlade data i form av medelvärden på gruppnivå från interventionsgruppen och kontrollgruppen, från elevernas resultat på förtest och eftertest och analyser av dessa som vi genomfört med hjälp av SPSS (ANOVA). I resultatet framkom att båda grupperna utvecklats men interventionsgruppen hade som helhet utvecklats och blivit signifikant bättre än kontrollgruppen. När det gällde begreppslig förmåga visade mätningarna på att interventionsgruppen hade blivit statiskt signifikant bättre än kontrollgruppen. Gällande procedurförmåga utvecklades båda grupperna och blev bättre, men mätningarna visade inte på någon signifikant skillnad mellan grupperna. Resultatet visade även på betydelsen av att fokusera på begreppslig förmåga och att använda sig av både konkret och abstrakt material, för att elever ska få djupare förståelse för området bråk, där användning av tallinjen underlättade för eleverna i interventionsgruppen att förstå att bråktals värde. Det är önskvärt med fler studier där äldre elever ingår då behovet är stort (många äldre elever befinner sig i matematiksvårigheter) och det finns få studier att ta del av.

• Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Ordinlärning: En undersökning av några mekanismers inverkan på ordinlärning för elever i årskurs 62020Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

Word learning is an important prerequisite for all knowledge acquisition. As special education teachers, we meet students who need support in developing their vocabulary and in order to provide the best possible support, we need to understand the mechanisms behind word learning. This study, which is part of a larger research project on word learning at Linköping University, aims to identify success factors and barriers when it comes to word learning. It is a quantitative study where, by replicating an experiment based on a computer program, we examine 18 pupils in year 6 to see how their word learning is affected by the structure of words based on the phenomena of phonotactic probability and neighbourhood density, as well as amount of exposure. We also investigate the prevalence and strength of correlations between the abilities of word learning, vocabulary, phonological ability and working memory.

The results show a significant main effect of the episode, the more times a word is repeated the better the test person reproduces the word correctly. Words appear to be learnt most readily when both phonotactic probability and neighbourhood density are high followed by low phonotactic probability and low neighbourhood density, which is in line with previous studies in other linguistic contexts.

The results also show a strong significant correlation between phonological ability and word learning as well as between vocabulary and word learning. Further there was a moderately strong significant correlation between phonological ability and working memory.

Our study showed that word learning benefited from repetition, across all word categories. According to our study, allowing students to meet new words several times is a confirmed success factor. We also saw that phonological ability seems to be of importance for the effectiveness of the student’s word learning. From a special education perspective, it seems vital already in early grades to identify pupils with weaker phonological ability.

• Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
"Det som funkar ena dagen kanske inte funkar om en vecka": En kvalitativ intervjustudie i grundsärskolan om lärares arbete med bedömningsstödet Gilla matematik samt den obligatoriska delen som rör talupfattning och tals användning2020Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis

Elevernas kunskapsutveckling ska utvärderas i relation till kunskapskraven i grundsärskolans läroplan där specialpedagogisk kompetens är en viktig del i lärarens arbete i att bedöma och skapa förutsättningar för varje enskild elevs lärande. Vid vårt arbete i grundsärskolan har vi uppfattat att lärares arbete med Skolverkets obligatoriska bedömningsstöd Gilla matematik skiljer sig åt mellan skolor. Många lärare uttrycker att arbetet är komplext i relation till en intellektuell funktionsnedsättning. Riksrevisionen gjorde 2019 en granskning av grundsärskolans kunskapsuppdrag som berör stöd och uppföljning från Skolverket och Sveriges regering, där slutsatsen visar att grundsärskolan inte har samma förutsättningar som grundskolan.

Utifrån de brister som granskningen lyfter fram samt lärarnas skilda uppfattningar om bedömningsstödet har studiens syfte och frågeställningar vuxit fram. Studiens syfte handlar om att bidra med kunskaper om lärares uppfattning om arbetet med grundsärskolans bedömningsstöd Gilla matematik och belyser lärarens perspektiv på arbetet med bedömningsstöd i relation till en intellektuell funktionsnedsättning. För att ta reda på detta genomfördes en kvalitativ forskningsstudie med inspiration av etnografi där 6 lärare intervjuades. Samtliga lärare arbetar med matematik i årskurs 1 och är verksamma i fem olika kommunala grundsärskolor i Mellansverige.

Resultatet visar att informanterna upplever att den gemensamma samsynen är viktig, för att stärka bedömningens kvalitet. En samsyn i hur bedömningsstödet kan användas i relation till materialets kunskapsnivåer och vad en intellektuell funktionsnedsättning kan innebära för den enskilde elevens förutsättningar vid olika bedömningstillfällen. Informanterna uttrycker att mer tid för pedagogiska samtal, specialpedagogiskt stöd och en ökad insyn från skolornas ledning skulle främja en samlad kunskapssyn och kompetensutveckling i arbetet med bedömningsstödet.

• Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
Department of Mathematics, Southern Methodist University, Dallas, TX 75275 USA.
The Number of Boundary Conditions for Initial Boundary Value Problems2020Report (Other academic)

Both the energy method and the Laplace transform method are frequently used for determining the number of boundary conditions required for a well posed initial boundary value problem.We show that these two distinctly dierent methods yield the same results.

• Public defence: 2020-03-06 10:15 K3, Kåkenhus, Norrköping
Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
Overcoming Limitations of Iontronic Delivery Devices2020Doctoral thesis, comprehensive summary (Other academic)

Organic electronic devices are considered as one of the best candidates to replace conventional inorganic electronic devices due to their electronic conductive functionality, low-cost production techniques, the ability to tune their optical and electronic properties using organic chemistry, and their mechanical flexibility. Moreover, these systems are ideal for bioelectronic applications due to their softness, biocompatibility, and most importantly, their electronic and ionic transport. Indeed, these materials are compatible with biological tissues and cells improving the signal transduction between electronic devices and electrically excitable cells. As ions serve as one of the primary signal carriers of cells, they can selectively tune a cell’s activity; therefore, an improved interface between electronics and biological systems can offer several advantages in healthcare, e.g. the development of efficient drug delivery devices.

The main focus of this thesis is the development of electronic delivery devices. Electrophoretic delivery devices called organic electronic ion pumps (OEIPs) are used to electronically control the delivery of small ions, neurotransmitters, and drugs with high spatiotemporal resolution. This work elucidates the ion transport processes and phenomena that happen in the ion exchange membranes during ion delivery and clarifies which parameters are crucial for the ion transport efficiency of the OEIPs. This thesis shows a systematic investigation of these parameters and indicates new methods and OEIP designs to overcome these challenges. Two novel OEIP designs are developed and introduced in this thesis to improve the local ion transport while limiting side effects. OEIPs based on palladium proton trap contacts can improve the membrane permselectivity and optimize the delivery of γ-aminobutyric acid (GABA) neurotransmitters at low pH while preventing any undesired pH changes from proton transport in the biological systems. And OEIPs based on glass capillary fibers are developed to overcome the limitations of devices on planar substrates, related to more complex and larger biologically relevant ion delivery with low mobility for implantable applications. This design can optimize the transport of ions and drugs such as salicylic acid (SA) at low concentrations and at relatively much higher rates, thereby addressing a wider range of biomedically relevant applications and needs.

1. pH Dependence of γ-Aminobutyric Acid Iontronic Transport
Open this publication in new window or tab >>pH Dependence of γ-Aminobutyric Acid Iontronic Transport
2017 (English)In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 121, no 30, p. 7284-7289Article in journal (Refereed) Published
##### Abstract [en]

The organic electronic ion pump (OEIP) has been developed as an “iontronic” tool for delivery of biological signaling compounds. OEIPs rely on electrophoretically “pumping” charged compounds, either at neutral or shifted pH, through an ion-selective channel. Significant shifts in pH lead to an abundance of H+ or OH–, which are delivered along with the intended substance. While this method has been used to transport various neurotransmitters, the role of pH has not been explored. Here we present an investigation of the role of pH on OEIP transport efficiency using the neurotransmitter γ-aminobutyric acid (GABA) as the model cationic delivery substance. GABA transport is evaluated at various pHs using electrical and chemical characterization and compared to molecular dynamics simulations, all of which agree that pH 3 is ideal for GABA transport. These results demonstrate a useful method for optimizing transport of other substances and thus broadening OEIP applications.

##### Place, publisher, year, edition, pages
American Chemical Society (ACS), 2017
##### National Category
Electrical Engineering, Electronic Engineering, Information Engineering Chemical Sciences
##### Identifiers
urn:nbn:se:liu:diva-139731 (URN)10.1021/acs.jpcb.7b05218 (DOI)000407189200007 ()28741949 (PubMedID)2-s2.0-85026913272 (Scopus ID)
##### Note

Funding agencies: EU Seventh Framework Programme [607896]; Knut and Alice Wallenberg Foundation [2012.0302]; Onnesjo Foundation

Available from: 2017-08-14 Created: 2017-08-14 Last updated: 2020-02-17Bibliographically approved
2. Overcoming transport limitations in miniaturized electrophoretic delivery devices
Open this publication in new window or tab >>Overcoming transport limitations in miniaturized electrophoretic delivery devices
2019 (English)In: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 19, no 8, p. 1427-1435Article in journal (Refereed) Published
##### Abstract [en]

Organic electronic ion pumps (OEIPs) have been used for delivery of biological signaling compounds, at high spatiotemporal resolution, to a variety of biological targets. The miniaturization of this technology provides several advantages, ranging from better spatiotemporal control of delivery to reduced invasiveness for implanted OEIPs. One route to miniaturization is to develop OEIPs based on glass capillary fibers that are filled with a polyelectrolyte (cation exchange membrane, CEM). These devices can be easily inserted and brought into close proximity to targeted cells and tissues and could be considered as a starting point for other fiber-based OEIP and iontronic technologies enabling favorable implantable device geometries. While characterizing capillary OEIPs we observed deviations from the typical linear current-voltage behavior. Here we report a systematic investigation of these irregularities by performing experimental characterizations in combination with computational modelling. The cause of the observed irregularities is due to concentration polarization established at the OEIP inlet, which in turn causes electric field-enhanced water dissociation at the inlet. Water dissociation generates protons and is typically problematic for many applications. By adding an ion-selective cap that separates the inlet from the source reservoir this effect is then, to a large extent, suppressed. By increasing the surface area of the inlet with the addition of the cap, the concentration polarization is reduced which thereby allows for significantly higher delivery rates. These results demonstrate a useful approach to optimize transport and delivery of therapeutic substances at low concentrations via miniaturized electrophoretic delivery devices, thus considerably broadening the opportunities for implantable OEIP applications.

##### Place, publisher, year, edition, pages
Royal Society of Chemistry, 2019
##### National Category
Analytical Chemistry
##### Identifiers
urn:nbn:se:liu:diva-157204 (URN)10.1039/c9lc00038k (DOI)000465283700008 ()30875418 (PubMedID)2-s2.0-85064156567 (Scopus ID)
##### Note

Funding Agencies|Swedish Foundation for Strategic Research; Advanced Functional Materials SFO-center at Linkoping University; Onnesjo Foundation; Knut and Alice Wallenberg Foundation

Available from: 2019-06-14 Created: 2019-06-14 Last updated: 2020-02-17Bibliographically approved
3. Modulating Inflammation in Monocytes Using Capillary Fiber Organic Electronic Ion Pumps
Open this publication in new window or tab >>Modulating Inflammation in Monocytes Using Capillary Fiber Organic Electronic Ion Pumps
2019 (English)In: Advanced Healthcare Materials, ISSN 2192-2640, E-ISSN 2192-2659, Vol. 8, no 19, article id 1900813Article in journal (Refereed) Published
##### Abstract [en]

An organic electronic ion pump (OEIP) delivers ions and drugs from a source, through a charge selective membrane, to a target upon an electric bias. Miniaturization of this technology is crucial and will provide several advantages, ranging from better spatiotemporal control of delivery to reduced invasiveness for implanted OEIPs. To miniaturize OEIPs, new configurations have been developed based on glass capillary fibers filled with an anion exchange membrane (AEM). Fiber capillary OEIPs can be easily implanted in proximity to targeted cells and tissues. Herein, the efficacy of such a fiber capillary OEIP for modulation of inflammation in human monocytes is demonstrated. The devices are located on inflammatory monocytes and local delivery of salicylic acid (SA) is initiated. Highly localized SA delivery results in a significant decrease in cytokine (tumor necrosis factor alpha and interleukin 6) levels after lipopolysaccharide stimulation. The findings-the first use of such capillary OEIPs in mammalian cells or systems-demonstrate the utility of the technology for optimizing transport and delivery of different therapeutic substances at low concentrations, with the benefit of local and controlled administration that limits the adverse effect of oral/systemic drug delivery.

WILEY, 2019
##### Keywords
bioelectronics; capillary fibers; cytokines; drug delivery; electrophoresis; inflammation; ion exchange membranes; iontronics; organic electronics
Biophysics
##### Note

Funding Agencies|Swedish Foundation for Strategic ResearchSwedish Foundation for Strategic Research [RIT15-0119]; Advanced Functional Materials SFO-Center at Linkoping University; International Interdisciplinary Laboratory for Advanced Functional Materials, Linkopings Universitet; Onnesjo Foundation; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation

Available from: 2019-10-25 Created: 2019-10-25 Last updated: 2020-02-17
• Public defence: 2020-03-06 09:00 Granitsalen, Building 448, Entrance 7, Linköping
Linköping University, Department of Biomedical and Clinical Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
Pharmacogenetic studies of thiopurine methyltransferase genotype-phenotype concordance and effect of methotrexate on thiopurine metabolism2020Doctoral thesis, comprehensive summary (Other academic)

The thiopurines (6-mercaptopurine [6-MP], 6-thioguanine and azathioprine) are cytotoxic drugs used in the treatment of acute lymphoblastic leukemia (ALL), inflammatory bowel diseases, certain autoimmune diseases and after transplantation. The metabolism of thiopurines is complex with several enzymes involved in the conversion into active drug metabolites. One of the enzymes, thiopurine methyltransferase (TPMT), is one of the best examples of implemented pharmacogenetics so far. Due to lowered TPMT enzyme activity caused by genetic polymorphism, carriers of heterozygous or homozygous defective TPMT alleles need dose reduction to avoid cytotoxic adverse reactions like myelosuppression or hepatotoxicity if treated with thiopurines.

To determine TPMT status before the start of treatment, genotyping (for the three most occurring TPMT alleles) and/or phenotyping (TPMT enzyme activity measurements) are used in the clinical setting. In the focus of this thesis, concordance of these methods was investigated in a large cohort of unique samples (n=12,663) collected in the routine analysis service of TPMT status determinations in Linköping. By sequencing all exons in samples where the results of the two methods differed, rare or novel TPMT alleles were discovered. Four TPMT alleles (TPMT*41, *42, *43, *44), not previously described, were characterized in terms of clinical in vivo data as well as protein structure and stability data obtained from recombinant human TPMT (rTPMT) produced by E. Coli and biophysical methods.

The clinical cohort was also used in the search for other factors (except genetic factors) that influence TPMT enzyme activity, and both age and gender turned out to affect TPMT enzyme activity level. In addition, TPMT enzyme activity in the early treatment of ALL was investigated and shown to be significantly lower at time of ALL diagnosis.

In the treatment protocol of ALL, the combined treatment using 6-MP and methotrexate (MTX) has increased the positive outcomes since the start in the 1950s. Despite this, the synergistic effect of these drugs is not yet fully understood. To evaluate the effect of MTX on thiopurine metabolism specifically, TPMT enzyme activity, TPMT gene expression, and thiopurine metabolite levels were determined before and after MTX infusions in vivo and after cotreatment in lymphoblasts in vitro. In the presence of MTX, TPMT enzyme activity and metabolite levels decreased, both in vivo and in vitro, although dose- and time-dependent. In addition, MTX bound to rTPMT and caused inhibition of rTPMT enzyme activity.

The results found in the scope of this thesis may be used for further individualization of thiopurine treatment.

1. Comprehensive study of thiopurine methyltransferase genotype, phenotype, and genotype-phenotype discrepancies in Sweden
Open this publication in new window or tab >>Comprehensive study of thiopurine methyltransferase genotype, phenotype, and genotype-phenotype discrepancies in Sweden
2019 (English)In: Biochemical Pharmacology, ISSN 0006-2952, E-ISSN 1356-1839, Vol. 164, p. 263-272Article in journal (Refereed) Published
##### Abstract [en]

Thiopurines are widely used in the treatment of leukemia and inflammatory bowel diseases. Thiopurine metabolism varies among individuals because of differences in the polymorphic enzyme thiopurine methyltransferase (TPMT, EC 2.1.1.67), and to avoid severe adverse reactions caused by incorrect dosing it is recommended that the patients TPMT status be determined before the start of thiopurine treatment. This study describes the concordance between genotyping for common TPMT alleles and phenotyping in a Swedish cohort of 12,663 patients sampled before or during thiopurine treatment. The concordance between TPMT genotype and enzyme activity was 94.5%. Compared to the genotype, the first measurement of TPMT enzyme activity was lower than expected for 4.6% of the patients. Sequencing of all coding regions of the TPMT gene in genotype/phenotype discrepant individuals led to the identification of rare and novel TPMT alleles. Fifteen individuals (0.1%) with rare or novel genotypes were identified, and three TPMT alleles (TPMT*42, *43, and *44) are characterized here for the first time. These 15 patients would not have been detected as carrying a deviating TPMT genotype if only genotyping of the most common TPMT variants had been performed. This study highlights the benefit of combining TPMT genotype and phenotype determination in routine testing. More accurate dose recommendations can be made, which might decrease the number of adverse reactions and treatment failures during thiopurine treatment.

##### Place, publisher, year, edition, pages
PERGAMON-ELSEVIER SCIENCE LTD, 2019
##### Keywords
Thiopurine; TPMT; Pharmacogenetics; Genotyping; Individualization
Hematology
##### Identifiers
urn:nbn:se:liu:diva-158047 (URN)10.1016/j.bcp.2019.04.020 (DOI)000469163900023 ()31005613 (PubMedID)
##### Note

Funding Agencies|Swedish Childrens Cancer Foundation; Medical Research Council of Southeast Sweden; Swedish Society of Medicine Linkoping; ostgOtaregionens cancerfond

Available from: 2019-06-25 Created: 2019-06-25 Last updated: 2020-02-17
2. One amino acid makes a difference-Characterization of a new TPMT allele and the influence of SAM on TPMT stability
Open this publication in new window or tab >>One amino acid makes a difference-Characterization of a new TPMT allele and the influence of SAM on TPMT stability
2017 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, article id 46428Article in journal (Refereed) Published
##### Abstract [en]

Thiopurine induced toxicity is associated with defects in the thiopurine methyltransferase (TPMT) gene. TPMT is a polymorphic enzyme, with most of the single nucleotide polymorphisms (SNPs) causing an amino acid change, altering the enzymatic activity of the TPMT protein. In this study, we characterize a novel patient allele c.719A amp;gt; C, named TPMT*41, together with the more common variant *3C c.719A amp;gt; G, resulting in an amino acid shift at tyrosine 240 to serine, p.Y240S and cysteine, p.Y240C respectively. We show that the patient heterozygote for c.719A amp;gt; C has intermediate enzymatic activity in red blood cells. Furthermore, in vitro studies, using recombinant protein, show that TPMT p.Y240S is less stable than both TPMTwt and TPMT p.Y240C. The addition of SAM increases the stability and, in agreement with Isothermal Titration Calorimetry (ITC) data, higher molar excess of SAM is needed in order to stabilize TPMT p.Y240C and TPMT p.Y240S compared to TPMTwt. Molecular dynamics simulations show that the loss of interactions is most severe for Y240S, which agrees with the thermal stability of the mutations. In conclusion, our study shows that SAM increases the stability of TPMT and that changing only one amino acid can have a dramatic effect on TPMT stability and activity.

##### Place, publisher, year, edition, pages
NATURE PUBLISHING GROUP, 2017
##### National Category
Biochemistry and Molecular Biology
##### Identifiers
urn:nbn:se:liu:diva-137842 (URN)10.1038/srep46428 (DOI)000400451400001 ()28462921 (PubMedID)
##### Note

Funding Agencies|LiU Cancer Network; Medical Research Council of Southeast Sweden; Lars Hiertas Memory Foundation; Samariten Foundation; Swedish Society of Medicine Linkoping; Ostgotaregionens Cancerfond; Swedish e-Science Research Center

Available from: 2017-06-02 Created: 2017-06-02 Last updated: 2020-02-17
3. Methotrexate binds to recombinant thiopurine S-methyltransferase and inhibits enzyme activity after high-dose infusions in childhood leukaemia
Open this publication in new window or tab >>Methotrexate binds to recombinant thiopurine S-methyltransferase and inhibits enzyme activity after high-dose infusions in childhood leukaemia
2013 (English)In: European Journal of Clinical Pharmacology, ISSN 0031-6970, E-ISSN 1432-1041, Vol. 69, no 9, p. 1641-1649Article in journal (Refereed) Published
##### Abstract [en]

Purpose

Important drugs in the treatment of childhood acute lymphoblastic leukaemia (ALL) are 6-mercaptopurine (6-MP) and methotrexate (MTX). Thiopurine methyltransferase (TPMT) is a polymorphic enzyme causing variability in 6-MP response and toxicity. The aim of this study was to investigate the fluctuation in TPMT enzyme activity over time and the effect of high-dose MTX infusions on TPMT enzyme activity and 6-MP metabolites in paediatric ALL patients.

Methods

Fifty-three children with ALL treated according to the NOPHO-ALL 2000 protocol were included in the study. TPMT enzyme activity was measured at six different times starting from diagnosis until after the end of maintenance treatment. TPMT and 6-MP metabolites were measured before the initiation of high-dose MTX (HD-MTX) infusions and at 66 h post-infusion. The interaction between MTX and TPMT was investigated in vitro using recombinant TPMT protein and a leukaemic cell line.

Results

Forty percent of TPMT wild-type individuals had deceptively low TPMT enzyme activity according to genotype at the time of diagnosis. TPMT activity had decreased significantly 66 h after the start of HD-MTX infusions (−9.2 %; p = 0.013). MTX bound to recombinant TPMT protein severely inhibiting TPMT enzyme activity (remaining activity 16 %).

Conclusions

Our results show that TPMT genotyping should be performed in children with ALL, since 40 % of the children in our study who carried the wild-type TPMT gene were at risk of initial underdosing of 6-MP in cases where only TPMT enzyme activity was determined. MTX inhibits the TPMT enzyme activity after HD-MTX infusions due to protein binding.

##### Place, publisher, year, edition, pages
Springer Berlin/Heidelberg, 2013
##### Keywords
Leukaemia, 6-mercaptopurine, methotrexate, pharmacogenetics, thiopurine s-methyltransferase
##### National Category
Natural Sciences
##### Identifiers
urn:nbn:se:liu:diva-80190 (URN)10.1007/s00228-013-1521-9 (DOI)000323429900003 ()
Available from: 2012-08-22 Created: 2012-08-22 Last updated: 2020-02-17Bibliographically approved
• Försvarshögskolan, Militärtekniska avdelningen (MTA), Stockholm, Sweden.
Försvarshögskolan, Militärtekniska avdelningen (MTA), Stockholm, Sweden. SAAB Aerosystems. Försvarshögskolan, Militärtekniska avdelningen (MTA), Stockholm, Sweden. Försvarshögskolan, Militärtekniska avdelningen (MTA), Stockholm, Sweden. Försvarshögskolan, Militärtekniska avdelningen (MTA), Stockholm, Sweden. Försvarshögskolan, Militärtekniska avdelningen (MTA), Stockholm, Sweden.
Military utility: A proposed concept to support decision-making2015In: Technology in society, ISSN 0160-791X, E-ISSN 1879-3274, Vol. 43, p. 23-32Article in journal (Refereed)

A concept called Military Utility is proposed for the study of the use of technology in military operations. The proposed concept includes a three-level structure representing key features and their detailed components. On basic level the Military Utility of a technical system, to a military actor, in a specific context, is a compound measure of the military effectiveness, of the assessed technical system's suitability to the military capability system and of the affordability. The concept is derived through conceptual analysis and is based on related concepts used in social sciences, the military domain and Systems Engineering. It is argued that the concept has qualitative explanatory powers and can support military decision-making regarding technology in forecasts, defense planning, development, utilization and the lessons learned process. The suggested concept is expected to contribute to the development of the science of Military-Technology and to be found useful to actors related to defense.

• Public defence: 2020-03-13 09:00 Hasselquistsalen, Building 511, Linköping
Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Health, Medicine and Caring Sciences, Division of Nursing Sciences and Reproductive Health.
Health-related quality of life after cardiac arrest2020Doctoral thesis, comprehensive summary (Other academic)

Background: Cardiac arrest is a major health problem worldwide. For many of the afflicted, cardiac arrest is the natural end of life. For others, it is an unexpected event suddenly striking in the middle of life. During the last decades, major efforts in treatment have contributed to more people surviving their cardiac arrest. However, previous research has mainly focused on survival, while the knowledge about health-related quality of life in survivors is sparse. Hence, there is a need for more research in order to extend the knowledge about the living situations among survivors and their spouses. For example, factors associated with health-related quality of life are not sufficiently investigated. Knowledge about such factors is important in order to develop interventions and to be able to improve post cardiac arrest care. In addition, existing research shows incongruent results concerning differences in characteristics and survival between men and women. In order to provide equitable care between sexes, further studies are warranted.

Aim: The overall aim of this thesis was to increase the knowledge of survival and health-related quality of life among people suffering cardiac arrest with focus on sex and other related factors. The specific aims were: to describe in-hospital cardiac arrest events with regard to sex and investigate if sex is associated with survival after controlling for known predictors and interaction effects (study I), to describe health status and psychological distress among in-hospital cardiac arrest survivors in relation to sex (study II), to investigate factors associated with health-related quality of life among cardiac arrest survivors treated with an implantable cardioverter defibrillator in relation to sex, and to compare their health-related quality of life with a general population, (study III) and to investigate if type D personality and perceived control among cardiac arrest survivors and their spouses were associated with their own and their partners’ health-related quality of life (study IV).

Methods: The general design in all studies (I-IV) was quantitative, cross-sectional and correlational. This thesis is based on four different data collections. Data was systematically collected using national quality registries (I and II) or by sending questionnaires to survivors (III and IV) and their spouses (IV), treated at several different hospitals in Sweden. The sample size varied between 126 and 990 across the studies. The outcomes and explanatory study variables were chosen with respect to Wilson and Cleary’s conceptual model of health-related quality of life. The main outcome variables were survival after resuscitation, survival at hospital discharge, survival at 30 days post cardiac arrest (I), and health-related quality of life measured by the Hospital Anxiety and Depression Scale (II and III) and the EuroQol-5 dimensions (II-IV). In this thesis descriptive and inferential statistics were applied. The main statistics consisted of logistic and linear regression analyses, and structural equation modelling.

Results: Male sex was associated with a better chance of survival to hospital discharge, but no associations between sex and survival after resuscitation or at 30 days were identified. More men than women received resuscitation attempts when suffering an in-hospital cardiac arrest (study I). Health-related quality of life among most cardiac arrest survivors was good (II-IV), even when compared to a general population (III). However, a significant proportion reported low health status and symptoms of anxiety and depression (II and III). Women reported worse health-related quality of life compared to men, and female sex was associated with poorer health-related quality of life in the multiple regression models (II and III). Several additional factors were identified to be associated with poorer health-related quality of life: being unemployed, having a type D personality, perceiving less control, suffering from more comorbidities and suffering from more ICD-related concerns (III). In addition, older age was associated with poorer (EQ VAS) or better (HADS Anxiety) health-related quality of life, depending of outcome measure (II). Moreover, perceived control and type D personality among the survivors were associated with health-related quality of life among their spouses, but not vice versa.

Conclusions: Although, sex does not appear to be an important predictor for survival, the difference between men and women regarding the proportion of resuscitation attempts should be further investigated. The majority of survivors and their spouses report good health-related quality of life similar to general populations. However, a substantial proportion suffer from health problems. Since women in general report worse health-related quality of life compared to men a higher proportion of women may be in need of support. Several factors associated with worse health-related quality of life were identified and might be used during follow-up and rehabilitation. For example, identifying type D personality might be important when screening patients at risk for health problems. Perceiving more control could be targeted by health-supportive interventions, for example person-centered care. Healthcare professionals should make efforts to identify survivors at risk of poor health-related quality of life and offer individualized support when needed. Characteristics among survivors were associated with health-related quality of life in their spouses. Including spouses in follow-up care is therefore important. Wilson and Cleary’s conceptual model for health-related quality of life appears to be applicable for choosing outcomes in cardiac arrest research and might be helpful when designing interventions to improve post cardiac arrest care.

1. Is there a difference in survival between men and women suffering in-hospital cardiac arrest?
Open this publication in new window or tab >>Is there a difference in survival between men and women suffering in-hospital cardiac arrest?
2014 (English)In: Heart & Lung, ISSN 0147-9563, E-ISSN 1527-3288, Vol. 43, no 6, p. 510-515Article in journal (Refereed) Published
##### Abstract [en]

Objectives: To describe in-hospital cardiac arrest (CA) events with regard to sex and to investigate if sex is associated with survival. Background: Previous studies exploring differences between sexes are incongruent with regard to clinical outcomes. In order to provide equality and improve care, further investigations into these aspects are warranted. Methods: This registry study included 286 CAs. To investigate if sex was associated with survival, logistic regression analyses were performed. Results: The proportion of CA with a resuscitation attempt compared to CA without resuscitation was higher among men. There were no associations between sex and survival when controlling for previously known predictors and interaction effects. Conclusions: Sex does not appear to be a predictor for survival among patients suffering CA where resuscitation is attempted. The difference regarding proportion of resuscitation attempts requires more attention. It is important to consider possible interaction effects when studying the sex perspective.

##### Place, publisher, year, edition, pages
Elsevier, 2014
##### Keywords
Heart arrest; Hospital; Sex; Survival; Predictor
##### National Category
Clinical Medicine
##### Identifiers
urn:nbn:se:liu:diva-112817 (URN)10.1016/j.hrtlng.2014.05.012 (DOI)000344837600007 ()25005828 (PubMedID)
##### Note

Funding Agencies|county council of Kalmar

Available from: 2015-01-08 Created: 2014-12-17 Last updated: 2020-02-17Bibliographically approved
2. Health status and psychological distress among in-hospital cardiac arrest survivors in relation to gender
Open this publication in new window or tab >>Health status and psychological distress among in-hospital cardiac arrest survivors in relation to gender
2017 (English)In: Resuscitation, ISSN 0300-9572, E-ISSN 1873-1570, Vol. 114, p. 27-33Article in journal (Refereed) Published
##### Abstract [en]

Aim: To describe health status and psychological distress among in -hospital cardiac arrest (IHCA) survivors in relation to gender. Methods: This national register study consists of data from follow-up registration of IHCA survivors 3-6 months post cardiac arrest (CA) in Sweden. A questionnaire was sent to the survivors, including measurements of health status (EQ-5D-5L) and psychological distress (HADS). Results: Between 2013 and 2015, 594 IHCA survivors were included in the study. The median values for EQ-5D-5L index and EQVAS among survivors were 0.78 (ql-q3 = 0.67-0.86) and 70 (ql -q3 = 50-80) respectively. The values were significantly lower (p amp;lt; 0.001) in women compared to men. In addition, women reported more problems than men in all dimensions of EQ-5D-5L, except self -care. A majority of the respondents reported no problems with anxiety (85.4%) and/or symptoms of depression (87.0%). Women reported significantly more problems with anxiety (p amp;lt; 0.001) and symptoms of depression (p amp;lt; 0.001) compared to men. Gender was significantly associated with poorer health status and more psychological distress. No interaction effects for gender and age were found. Conclusions: Although the majority of survivors reported acceptable health status and no psychological distress, a substantial proportion reported severe problems. Women reported worse health status and more psychological distress compared to men. Therefore, a higher proportion of women may be in need of support. Health care professionals should make efforts to identify health problems among survivors and offer individualised support when needed. (C) 2017 Elsevier B.V. All rights reserved.

##### Place, publisher, year, edition, pages
ELSEVIER IRELAND LTD, 2017
##### Keywords
Anxiety; Depression; Health status; Heart arrest; Hospitals; Gender
##### National Category
Public Health, Global Health, Social Medicine and Epidemiology
##### Identifiers
urn:nbn:se:liu:diva-138921 (URN)10.1016/j.resuscitation.2017.02.006 (DOI)000402487800021 ()28216089 (PubMedID)
##### Note

Funding Agencies|Swedish Heart and Lung Association; Medical Research Council of Southeast Sweden

Available from: 2017-06-27 Created: 2017-06-27 Last updated: 2020-02-17
3. Factors associated with health-related quality of life among cardiac arrest survivors treated with an implantable cardioverter-defibrillator
Open this publication in new window or tab >>Factors associated with health-related quality of life among cardiac arrest survivors treated with an implantable cardioverter-defibrillator
2018 (English)In: Resuscitation, ISSN 0300-9572, E-ISSN 1873-1570, Vol. 132, p. 78-84Article in journal (Refereed) Published
##### Abstract [en]

Aim: To explore factors associated with health-related quality of life (HRQoL) among cardiac arrest (CA) survivors treated with an implantable cardioverter-defibrillator (ICD) in relation to gender, and to compare their HRQoL with a general population. Methods: This cross-sectional study included 990 adults treated with an ICD after suffering CA. All participants received a questionnaire including demographics, comorbidities and instruments to measure HRQoL (EQ-5D-3L and HADS), ICD-related concerns (ICDC), perceived control (CAS), and type D personally (DS-14). HRQoL (EQ-5D-3L) was compared to a general Swedish population, matched for age and gender. Linear regression analyses were used to explore factors associated with HRQoL. Results: The CA survivors reported better HRQoL in EQ index and less pain/discomfort compared to the general population (p amp;lt; 0.001). In contrast, they reported more problems in mobility and usual activities (p amp;lt; 0.01). Problems with anxiety and depression were reported by 15.5% and 7.4% respectively. The following factors were independently associated with all aspects of worse HRQoL: being unemployed, suffering more comorbidity, perceiving less control, and having a type D personally. Further, being female and suffering ICD-related concerns were independently associated with worse HRQoL in three of the four final regression models. Conclusions: This extensive population-based study showed that most CA survivors living with an ICD rate their HRQoL as acceptable. In addition, their HRQoL is similar to a general population. Women reported worse HRQoL compared to men. Several factors associated with HRQoL were identified, and might be used when screening patients for health problems and when developing health promoting interventions.

##### Place, publisher, year, edition, pages
ELSEVIER IRELAND LTD, 2018
##### Keywords
Health-related quality of life; Health status; Psychological distress; Cardiac arrest; Implantable cardioverter-defibrillator; Gender
##### National Category
Public Health, Global Health, Social Medicine and Epidemiology
##### Identifiers
urn:nbn:se:liu:diva-152373 (URN)10.1016/j.resuscitation.2018.09.002 (DOI)000446854900019 ()30201535 (PubMedID)
##### Note

Funding Agencies|Medical Research Council of Southeast Sweden; Swedish Heart and Lung Association

Available from: 2018-11-05 Created: 2018-11-05 Last updated: 2020-02-17
4. Dyadic effects of type D personality and perceived control on health-related quality of life in cardiac arrest survivors and their spouses using the actor-partner interdependence model
Open this publication in new window or tab >>Dyadic effects of type D personality and perceived control on health-related quality of life in cardiac arrest survivors and their spouses using the actor-partner interdependence model
2019 (English)In: European Journal of Cardiovascular Nursing, ISSN 1474-5151, E-ISSN 1873-1953, article id UNSP 1474515119890466Article in journal (Refereed) Epub ahead of print
##### Abstract [en]

Background: There is a lack of knowledge about factors associated with health-related quality of life in cardiac arrest survivors and their spouses. In addition, survivors and spouses are likely to affect each others health-related quality of life. Aims: The aim was to investigate if a distressed personality and perceived control among cardiac arrest survivors and their spouses were associated with their own and their partners health-related quality of life. Methods: This dyadic cross-sectional study used the actor-partner interdependence model to analyse associations between a distressed personality (type D personality), perceived control (control attitudes scale), and health-related quality of life (EQ index and EQ visual analogue scale). Results: In total, 126 dyads were included in the study. Type D personality and perceived control in cardiac arrest survivors were associated with their own health-related quality of life. In their spouses, a significant association was found for type D personality but not for perceived control. In addition, type D personality and perceived control in survivors were associated with health-related quality of life in their spouses. Conclusions: Type D personality and perceived control are factors that might be considered during post cardiac arrest, because of the associations with health-related quality of life in survivors and spouses. More research is needed to test psychosocial interventions in the cardiac arrest population in order to improve health-related quality of life.

##### Place, publisher, year, edition, pages
SAGE PUBLICATIONS LTD, 2019
##### Keywords
Heart arrest; survivor; partner; health; quality of life; dyads
##### National Category
Public Health, Global Health, Social Medicine and Epidemiology
##### Identifiers
urn:nbn:se:liu:diva-162500 (URN)10.1177/1474515119890466 (DOI)000498130000001 ()31752502 (PubMedID)
##### Note

Funding Agencies|Swedish Heart and Lung AssociationSwedish Heart-Lung Foundation; Medical Research Council of Southeast Sweden

Available from: 2019-12-16 Created: 2019-12-16 Last updated: 2020-02-17
• Linköping University, Department of Thematic Studies. Linköping University, Faculty of Arts and Sciences.
Gay male parenting in Greece: Examining families of choice2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis

This thesis aims to look at the topic of gay male parenting in Greece by focusing on how heteronormativity is forming the norms and the stereotypes that may affect gay men’s decisions and lives. By invoking a queer theory framework and through semistructured interviews with male gay couples, this study is engaging on their experiences and their opinions and attempts to produce new knowledge let their voices be heard. By using the lived experience of the participants, this study provides an inside perspective and combines theoretical knowledge with real-life issues and situations. Drawing on the concept of queer kinship and Kate Weston’s families of choice”, I am questioning the feasibility of this new family formation in Greece.

• Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Mekanismer som påverkar vid ordinlärning - en komplex process: En experimentell studie i årskurs 1 kring påverkansfaktorerna fonotaktisk sannolikhet och grannordstäthet2020Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

Ordförrådet är en central del i språkförståelsen. Forskning visar att svårigheter inom detta område kan leda till sämre förutsättningar att utvecklas kunskapsmässigt i skolan. Därför är det betydelsefullt att speciallärarens arbete är evidensbaserat för att främja och utveckla ordförrådet hos eleverna. Ordinlärning är ett komplext område med många ingående delar. Två variabler som har undersökts i internationell forskning för att få kunskap om ordinlärningsprocessen är fonotaktisk sannolikhet och grannordstäthet. Att brister i fonologisk medvetenhet försvårar ordinlärning har också uppmärksammats. I vårt arbete utfördes ett ordinlärningsexperiment och tre språkliga/kognitiva tester med 16 elever i årskurs 1 med typisk utveckling. I experimentet varierades ords fonotaktiska sannolikhet och grannordstäthet i syfte att undersöka vilken roll dessa variabler hade vid ordinlärning. Eleverna fick lyssna på två olika berättelser där 16 non-ord presenterades. Målet var att försöka lära sig dessa ord. Vi undersökte också, genom ett test i fonologisk medvetenhet, hur sambandet såg ut mellan ordinlärning och fonologisk medvetenhet. I studien uppnås inte ett signifikant resultat för variablernas påverkan vid ordinlärning. Däremot kan en ordinlärningsprogression säkerställas allteftersom exponeringarna för non-orden ökar. Korrelation mellan ordinlärning och fonologisk medvetenhet påvisas inte. Studiens resultat beror på att golveffekter uppnås i samband med experimentet. Eleverna lär sig få ord, vilket beror på att testet är för svårt. Framtida forskning bör vid liknande experiment med aktuell åldersgrupp beakta och överväga ett större urval, öka antalet exponeringar av målorden i testsituationen samt ändra rättningsförfarandet

• Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Faculty of Educational Sciences.
Vad är språkstörning: och vad vet lärare om diagnosen?2018Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

För att få större inblick i begreppet språkstörning samt för att utröna vad pedagoger verksamma i förskoleklass och årskurs 1 - 3 upplever sig ha för kompetens gällande språkstörning har jag utifrån följande frågeställningar:

- Vilka uppfattningar har lärare i förskoleklass och årskurs 1 - 3 om språkstörning? - Hur uppfattar de sin egen kompetens i fråga om språkstörning?

i sex kvalitativa semistrukturerade intervjuer tagit del av lärares uppfattningar om språkstörning och deras uppfattningar om sin kompetens i fråga om diagnosen språkstörning.

Analysen av empirin tyder på att lärarna har en relativt vag uppfattning om begreppets mångfacetterade innebörd. Trots den osäkerhet som lärarna säger sig uppleva kring vad språkstörning innebär, beskriver de ändå olika yttringar hos barn och elever som skulle kunna tyda på språkstörning. Ingen av de intervjuade ger en samlad bild av vad språkstörning innebär. Det förefaller som att lärarna inte till fullo är medvetna om att det är så pass många delar av språket som faktiskt kan vara inblandade då det gäller språkstörning. Några av lärarna innehar kunskaper kring vissa delar av diagnosen, ofta beroende på egna erfarenheter av elever med språkstörning. Flera nämner sig ha en känsla av att någonting inte stämmer men de kan inte definiera vad, mer än att det skulle kunna röra sig om språksvårigheter.

Ingen av lärarna har fått kompetensutveckling inom området. Den kompetens de besitter säger de sig ha fått via återgivning av logopedutredningar eller i samtal med talpedagog. De uppfattar sin egen kompetens som begränsad och känner sig i stort behov av kompetensutveckling.

Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
Time of Flight Estimation for Radio Network Positioning2020Doctoral thesis, comprehensive summary (Other academic)

Trilateration is the mathematical theory of computing the intersection of circles. These circles may be obtained by time of flight (ToF) measurements in radio systems, as well as laser, radar and sonar systems. A first purpose of this thesis is to survey recent efforts in the area and their potential for localization. The rest of the thesis then concerns selected problems in new cellular radio standards as well as fundamental challenges caused by propagation delays in the ToF measurements, which cannot travel faster than the speed of light. We denote the measurement uncertainty stemming from propagation delays for positive noise, and develop a general theory with optimal estimators for selected distributions, which can be applied to trilateration but also a much wider class of estimation problems.

The first contribution concerns a narrow-band mode in the long-term evolution (LTE) standard intended for internet of things (IoT) devices. This LTE standard includes a special position reference signal sent synchronized by all base stations (BS) to all IoT devices. Each device can then compute several pair-wise time differences that correspond to hyperbolic functions. The simulation-based performance evaluation indicates that decent position accuracy can be achieved despite the narrow bandwidth of the channel.

The second contribution is a study of how timing measurements in LTE can be combined. Round trip time (RTT) to the serving BS and time difference of arrival (TDOA) to the neighboring BS are used as measurements. We propose a filtering framework to deal with the existing uncertainty in the solution and evaluate with both simulated and experimental test data. The results indicate that the position accuracy is better than 40 meters 95% of the time.

The third contribution is a comprehensive theory of how to estimate the signal observed in positive noise, that is, random variables with positive support. It is well known from the literature that order statistics give one order of magnitude lower estimation variance compared to the best linear unbiased estimator (BLUE). We provide a systematic survey of some common distributions with positive support, and provide derivations and summaries of estimators based on order statistics, including the BLUE one for comparison. An iterative global navigation satellite system (GNSS) localization algorithm, based on the derived estimators, is introduced to jointly estimate the receiver’s position and clock bias.

The fourth contribution is an extension of the third contribution to a particular approach to utilize positive noise in nonlinear models. That is, order statistics have been employed to derive estimators for a generic nonlinear model with positive noise. The proposed method further enables the estimation of the hyperparameters of the underlying noise distribution. The performance of the proposed estimator is then compared with the maximum likelihood estimator when the underlying noise follows either a uniform or exponential distribution.

1. Performance of OTDOA Positioning in Narrowband IoT Systems
Open this publication in new window or tab >>Performance of OTDOA Positioning in Narrowband IoT Systems
2017 (English)In: 28th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC): Proceedings, IEEE, 2017Conference paper, Published paper (Refereed)
##### Abstract [en]

Narrowband Internet of Things (NB-IoT) is an emerging cellular technology designed to target low-cost devices, high coverage, long device battery life (more than ten years), and massive capacity. We investigate opportunities for device tracking in NB-IoT systems using Observed Time Difference of Arrival (OTDOA) measurements. Reference Signal Time Difference (RSTD) reports are simulated to be sent to the mobile location center periodically or on an ondemand basis. We investigate the possibility of optimizing the number of reports per minute budget on horizontal positioning accuracy using an on-demand reporting method based on the Signal to Noise Ratio (SNR) of the measured cells received by the User Equipment (UE). Wireless channels are modeled considering multipath fading propagation conditions. Extended Pedestrian A (EPA) and Extended Typical Urban (ETU) delay profiles corresponding to low and high delay spread environments, respectively, are simulated for this purpose. To increase the robustness of the filtering method, measurement noise outliers are detected using confidence bounds estimated from filter innovations.

IEEE, 2017
##### National Category
Communication Systems Control Engineering Signal Processing
##### Identifiers
urn:nbn:se:liu:diva-142819 (URN)10.1109/PIMRC.2017.8292365 (DOI)000426970901053 ()978-1-5386-3531-5 (ISBN)978-1-5386-3529-2 (ISBN)
##### Conference
28th Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC), Montreal, QC, Canada, 08-13 October, 2017
##### Projects
Tracking in complex sensor systems, TRAX Available from: 2017-11-06 Created: 2017-11-06 Last updated: 2020-02-16
2. Fusion of TOF and TDOA for 3GPP Positioning
Open this publication in new window or tab >>Fusion of TOF and TDOA for 3GPP Positioning
2016 (English)In: Fusion 2016, 19th International Conference on Information Fusion: Proceedings, Institute of Electrical and Electronics Engineers (IEEE), 2016, p. 1454-1460Conference paper, Published paper (Refereed)
##### Abstract [en]

Positioning in cellular networks is often based on mobile-assisted measurements of serving and neighboring base stations. Traditionally, positioning is considered to be enabled when the mobile provides measurements of three different base stations. In this paper, we additionally investigate positioning based on time series of Time Of Flight (TOF) and Time Difference of Arrival (TDOA) measurements gathered from two base stations with known positions, where the specific base stations involved depend on the trajectory of the mobile station.. The set of two base stations is different along the trajectory. Each report contains TOF for the serving base station, and one TDOA measurement for the most favorable neighboring base station relative the serving base station. We derive explicit analytical solution related to the intersection of the absolute distance circle (from TOF) and relative distance hyperbola (from TDOA). We consider both geometric noise-free problem and the more realistic problem with additive noise as delivered in the 3rd Generation Partnership Project (3GPP) Long-Term Evolution (LTE). Positioning performance is evaluated using the Cramer-Rao lower bound.

##### Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2016
##### National Category
Control Engineering
##### Identifiers
urn:nbn:se:liu:diva-130209 (URN)000391273400193 ()978-0-9964527-4-8 (ISBN)
##### Conference
19th International Conference on Information Fusion, Heidelberg, Germany, July 5-8, 2016
TRAX
##### Funder
EU, FP7, Seventh Framework Programme, 607400 Available from: 2016-07-15 Created: 2016-07-15 Last updated: 2020-02-16Bibliographically approved
• Linköping University, Department of Behavioural Sciences and Learning.
Undervisningsmetod som kan bidra till ökad kunskap: - lärares upplevelser av entreprenöriell undervisning som inslag i deras repertoarer2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis

I denna studie ligger fokus på hur lärare i årskurserna 1-3 uppfattar begreppet ”entreprenöriell undervisning”. Lärares uppfattningar angående förståelse av begreppet, och tillämpning av begreppet kommer ställas mot mer fastställda undervisningsmetoder; som i studien representeras av traditionell- och problemlösningsbaserad undervisning. För att få ta del av lärares upplevelse är insamlad data hämtad med metoden semistrukturerade intervjuer, som är en kvalitativ forskningsmetod och passar i en fenomenografiskt inspirerad studie där man intresserar sig för hur ett fenomen upplevs. I studiens bakgrundsavsnitt beskrivs komplexiteten i läraryrket och i teoriavsnittet förankras de tre undervisningsmetoderna i pedagogiska teorier.

I resultatet finns ett urval av direkta citat från de sex informanterna som deltagit i studien. De beskriver sin syn av de olika undervisningsmetodernas begrepp och hur de använder sig av metoderna i praktiken genom att ge skildringar av hur en lektion kan se ut med specifik undervisningsmetod. De berättar vidare vad lärare tar för roll i klassrummet och hur interaktionerna med elever upplevs då aktuell metod används. Informanternas svar visar att det finns likheter, skillnader och variationer i lärares erfarenheter av studiens undervisningsmetoder, och de risker som nämns visar komplexiteten i läraryrket. För lärandet är en resa för både elev och lärare. Varje elev som en lärare möter befinner sig i olika inlärningsfaser. För att kunna möta, utmana och återkoppla utifrån varje elevs behov måste lärare behärska olika undervisningsmetoder. Ska det även ske en progressiv utveckling måste de undervisningsmetoderna vara medvetna och noga planerade (Hattie 2009).

Det finns dock en gemensam och tydlig ståndpunkt, lärare vill att elever ska lyckas!

• Linköping University, Department of Computer and Information Science.
Linköping University, Department of Computer and Information Science.
Engaging novice programmers through gamification: Puzzles to teach and motivate programming learning2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

With an increasing number of primary schools having programming as a mandatory subject, students and teachers face new challenges by having to teach and learn a subject that is often difficult to engage students in. Many tools exist that introduce the problem solving aspect of programming, using a programming language not used in actual software. The programming languages used in these tools are often easier to understand and therefore engage the students more. In this study, an application teaching programming in Python is proposed while still engaging the students by including gamification elements. By having two groups of users, one group with gamification elements available in the software, and the other with them unavailable, the engagement could be compared between the two groups. With the data collected from Google Analytics, completion rate and surveys, it was shown that users with gamification elements available are slightly more engaged. Through the results gathered from this study, the use of gamification elements in this type of software can have an impact on user engagement and should therefore be considered when building similar types of systems.

• Linköping University, Department of Electrical Engineering, Computer Vision.
Classification of Clothing Attributes Across Domains2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

Classifying clothing attributes in surveillance images can be useful in the forensic field, making it easier to, for example, find suspects based on eyewitness accounts. Deep Neural Networks are often used successfully in image classification, but require a large amount of annotated data. Since labeling data can be time consuming or difficult, and it is easier to get hold of labeled fashion images, this thesis investigates how the domain shift from a fashion domain to a surveillance domain, with little or no annotated data, affects a classifier.

In the experiments, two deep networks of different depth are used as a base and trained on only fashion images as well as both labeled and unlabeled surveillance images, with and without domain adaptation regularizers. The surveillance dataset is new and consists of images that were collected from different surveillance cameras and annotated during this thesis work.

The results show that there is a degradation in performance for a classifier trained on the fashion domain when tested on the surveillance domain, compared to when tested on the fashion domain. The results also show that if no labeled data in the surveillance domain is used for these experiments, it is more effective to use the deeper network and train it on only fashion data, rather than to use the more complicated unsupervised domain adaptation method.

• Linköping University, Department of Thematic Studies.
Water and Wastewater Management in the Mega City Istanbul: A General Analysis from a Supply-Demand-Reuse Perspective2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

With a population of over 13 million, Istanbul is one of the biggest city in Europe. The possible increase of population in the future may bring serious problems of water supply after a few decades. Therefore, it is crucial to look for good solutions to problems and potential challenges in water supply and water demand. This paper intended to investigate the currently existing problems in water and wastewater management practices in Istanbul from a supply-demand-reuse perspective; and to look for possible opportunities for a future improvement in order to achieve a sustainable urban water management system in Istanbul by promoting its wastewater management system. In this paper, two interviews of professionals, and a survey in Istanbul city area were conducted for obtaining gather primary data. Analysis of relative literatures is applied for grasping an accurate picture of water and wastewater management in Istanbul. According to the study, authorities are making great efforts to meet the ever increasing demand for water. From a supply-demand-reuse management perspective, Istanbul is still at the stage of supply management with sufficient wastewater treatment. However, there is not much sign of a demand management model, as inadequate effort has been devoted to controlling the increase of water demand. Although reuse management may still be a distant goal for Istanbul to achieve, a good preparation can be started by promoting and further improving the current wastewater management system, as wastewater reuse, if properly managed, will be the best solution that will lead to achieving long-term benefits.

• Linköping University, Department of Computer and Information Science, Human-Centered systems.
Colour Image Search for Graphical Design Inspiration2020Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis

This thesis project aims to develop a search algorithm which uses the colour information in uncompleted graphical work to find inspirational images that utilizes similar colour schemes. The dominant colours are separated from the image, and those are used to find other images with similar palettes in a database. The system is intended as part of an inspirational mood board, and the user case this project is based on handles the design of a book cover, and the selection of images used to be searched through consists entirely of book covers. The development is done in OpenCV and C++, using the k-means cluster method. The results are inconsistent, and while the fault in the system is known, it has yet to be mended.

• Linköping University, Department of Medical and Health Sciences.
Linköping University, Department of Medical and Health Sciences.
Patienters och fysioterapeuters upplevelser av fysioterapeutisk behandling vid endometrios: En kvalitativ intervjustudie2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

Background: In Sweden approximately 200.000 women have been diagnosed with endometriosis. Endometrial-like tissue is growing outside the uterus. The development of endometriosis could be multifactorial, caused by retrograde menstruation combined with hormonal factors, heredity and a weakened local immune system. Common symptoms are different variations of pain, infertility and decreased quality of life. The purpose of the treatment is to ensure a good level of functioning with manageable symptoms. Physical therapy is highly recommended when treating endometriosis.

Purpose: To investigate the experiences of physical therapy treatment in endometriosis according to patients and physiotherapists.

Method: Six semi-structured interviews were conducted, of which three were including patients with endometriosis and three were including physiotherapists. The data was analyzed through qualitative content analysis.

Results: The analysis resulted in four main categories: “Adaptation based on the individual patient”, “Purpose and effect of the treatment”, “Emotional experiences and factors that contribute to power and hope” and “The role of the physiotherapist”. The physical therapy was perceived as focusing on the patient´s needs. It was unanimously agreed that the treatment reduced symptoms and could engender delight mingled with terror, but also hope. The physical therapy treatment was found to provide safety and assistance.

Conclusion: Physical therapy in endometriosis can be experienced as valuable for reducing pain and muscle tension and for providing coping strategies in everyday life. The physiotherapist was found to be able to make the patients feel heard, seen and helped.

• Linköping University, Department of Health, Medicine and Caring Sciences.
Linköping University, Department of Health, Medicine and Caring Sciences.
Fysioterapeuters upplevelser av Basal Kroppskännedom som behandling vid posttraumatiskt stressyndrom: En kvalitativ intervjustudie2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

Introduction: Posttraumatic Stress Disorder (PTSD) is a psychiatric diagnosis as a result of an exposure to an earlier traumatic experience. Basic Body Awareness Therapy (BBAT) is a physiotherapeutic treatment where the purpose is to make the patient more aware of their own body. Earlier studies have investigated the effects and experiences of the BBAT as treatment for PTSD but the physiotherapist’s perspective in the field have not yet been investigated.

Purpose: To investigate physiotherapist’s experiences of Basic Body Awareness Therapy as treatment for Posttraumatic Stress Disorder.

Method: Qualitative interview study. Seven physiotherapist’s with therapeutic competence in BBAT were interviewed using semi-structured interview. Qualitative content analysis where used to analyse data.

Results: Three categories and ten subcategories where identified. Approaches and roles between patient and physiotherapist described experiences of the interaction between the physiotherapist and patient. The physiotherapist’s strategy and treatment described reasoning about evaluation and treatment of patients. BBAT:s function as a treatment described experiences of the patient group, BBAT:s role as treatment together with other therapies and experiences of the situation in the health-care system for PTSD today.

Conclusion: BBAT is described by physiotherapist’s as a respectful and adaptable method to implement in treating post-traumatic issues. There is an experienced need in using the body as a starting point in order to process and manage trauma. BBAT can be used as a complement or first-line treatment in treating patients with PTSD.

• Linköping University, Department of Medical and Health Sciences.
Linköping University, Department of Medical and Health Sciences.
Aktiv återhämtning hos tävlingssimmare: En jämförelse mellan aktiv återhämtning med och utan simfenor2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

Introduction: It is common among swimmers to use fins during active recovery. There is limited research about how fins decrease blood lactate, pulse, rating of perceived exertion and evaluation of leg and arm exertion.

Objective: The study compared active recovery in relation to blood lactate, pulse, rating of perceived exertion and evaluation of leg and arm exertion while swimming with and without short fins.

Method: A cross-over pilot study was designed in which 11 swimmers took part. Blood lactate, pulse, rating of perceived exertion and evaluation of leg and arm exertion were examined on two test days during which the swimmers swam 100 meters freestyle max followed by a 10-minute active recovery with or without fins, depending on test day.

Results: Ten swimmers completed the study. No significant difference was found between test days 1 and 2 for pulse, blood lactate, Borg RPE and Borg CR10. Eight out of ten participants had lower blood lactate when they used fins during active recovery than when they did not. A minor correlation between blood lactate and Borg RPE and Borg CR10 was indicated by the data, but not strong enough to ensure a correlation.

Conclusion: No significant difference between active recovery with and without fins was found. Additional studies with a larger study population are necessary for more reliable results.

• Linköping University, Department of Behavioural Sciences and Learning.
Lärares upplevelse av vad som kännetecknar ett gott ledarskap2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis

Anledningen till att denna studie utforma sig var mina funderingar om att ledarskapet i klassrummet är beroende av hur man bemöter eleverna. Genom en semistrukturerad intervjustudie ska fyra verksamma lärare få uttrycka sina föreställningar och upplevelser kring vad som kännetecknar ett gott ledarskap och dess olika beståndsdelar. Hela studien och studiens resultat bygger på att samla data om lärares upplevelser kring frågeställningarna. Studien ses ur ett fenomenologiskt perspektiv och analyseras med inspiration från the grounded theory. Dessa två metoder passar bra ihop då de vill fånga undersökningsdeltagarnas upplevelser av ett fenomen och dess olika aspekter.

Utifrån informanternas upplevelser beskrivs olika aspekter på fenomenet relationellt ledarskap och strategier för relationsarbetet. I denna studie kommer du att få ta del av informanternas beskrivningar av olika aspekter på relationellt ledarskap och vilka relationella strategier de säger att de använder. Aspekterna som berör och kopplas till det relationella ledarskapet är: Föredömlig, social, personlig, anpassningsbar, auktoritativ och ämneskunnig.

I studiens resultat presenteras deras upplevelser och kopplas till olika teorier kring ledarskap och relationsskapande i klassrummet. I stora drag visar denna studie att informanterna upplever att lärare som främjar relationer både mellan eleverna och mellan dem själva och eleverna utövar ett gott ledarskap eller ”lärarskap”.

• Linköping University, Department of Mathematics. Linköping University, Faculty of Science & Engineering.
Läroböckers påverkan på elevers begreppsbilder av likhetstecknet: En kvantitativ innehållsanalys om algebraiska standard- och icke-standardekvationers förekomst i läroböcker2020Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

Studien består av en kvantitativ innehållsanalys som åskådliggör förekomsten samt skillnaderna i förekomsten av algebraiska standard- och icke-standardekvationer i en läromedelserie anpassad för årskurs 7-9. Resultaten diskuteras i förhållande till Sfards teoretiska ramverk som beskriver hur begreppsbilder utvecklas hos individer samt forskning som fastställt att algebraiska icke-standardekvationer, framförallt icke-standardekvationer med operationer i både V.L. (vänster led) och H.L. (höger led), lämpar sig bra för att utveckla elevers förståelse för likhetstecknets relationella betydelse och således elevers strukturella begreppsbild av likhetstecknet.

Resultatet i föreliggande studie pekar på att läroboken för årskurs 7 till största del innehåller algebraiska standardekvationer vilket kan hindra elevernas utveckling till en strukturell och istället bidra till en operationell begreppsbild av likhetstecknet. Läroboken för årskurs 8 innehåller stor del icke-standardekvationer vilken kan främja elevers utveckling till en strukturell begreppsbild av likhetstecknet. Läroboken för årskurs 9 innehåller få standard- och icke-standardekvationer vilket kan hindra elever, som inte besitter förståelse för likhets- tecknets relationella betydelse, att utveckla en strukturell begreppsbild av likhetstecknet.

• Linköping University, Department of Computer and Information Science.
Taint analysis for automotive safety using the LLVM compiler infrastructure2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

Software safety is getting more and more important in the automotive industry as mechanical functions are replaced by complex embedded computer systems. Errors  during development can lead to accidents and threaten users’ lives. The safety level of the software must therefore be monitored through Automotive Safety Integrity Levels (ASILs), according to the standard ISO 26262. This thesis presents the development of a static taint analysis tool using the LLVM compiler infrastructure in order to identify safety-critical components and analyze their dependencies in automotive software. The aim was to provide a useful visualization tool to help safety engineers in their work and save time during development. It was concluded that this static taint analysis tool can facilitate and improve the precision of the ASIL decomposition of automotive software.

• Linköping University, Department of Computer and Information Science, Software and Systems.
Linköping University, Department of Computer and Information Science, Software and Systems.
Systematically uncovering mutants in testing safety critical software: Using symbolic execution on surviving mutants from mutation testing2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

This thesis investigates how symbolic execution and constraint solving can be used for detecting equivalent and non-equivalent mutants in mutation testing. The presented method proposes a driver implementation, realized as a plugin for Dextool, to differentiate original and mutated code from each other by executing both versions symbolically using KLEE. The method was tried on a number of code examples, uncovering equivalent and non-equivalent mutants successfully. It was concluded that detection of equivalent and non-equivalent mutants was possible and relevant for mutation testing, but with limitations in terms of scalability and applicability due to increasing amount of side effects, path explosion and certain functions not being suitable for symbolic execution.

• Department of Technology Management and Economics, Chalmers University of Technology, Göteborg, Sweden.
Linköping University, Department of Management and Engineering, Project Innovations and Entrepreneurship. Linköping University, Faculty of Science & Engineering. Linköping University, HELIX Competence Centre. Linköping University, Department of Management and Engineering, Project Innovations and Entrepreneurship. Linköping University, Faculty of Arts and Sciences.
Science Parks and talent attraction management: university students as a strategic resource for innovation and entrepreneurship2020In: European Planning Studies, ISSN 0965-4313, E-ISSN 1469-5944, p. 1-24Article in journal (Refereed)

This paper aims to expand our understanding of talent attraction management in Science Parks with a specific interest in university students/alumni as a human and strategic resource. The underlying rationale is how the links with universities can be supported and how the Science Park management can contribute to successful relationships with universities and university students/alumni, in order to develop tenant firms and the park itself. A questionnaire was sent out in 2018–120 parks. This study includes 25 variables, and four significant regression models are presented. The main finding is that Science Park talent attraction activities act as a mediating variable, which affects the informal and formal partnerships between students and firms/universities as well as how the park management can contribute to successful relationships. By attracting students, tenant firms can have a positive impact on their performance as well as Science Park development.

• Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
Railway Traffic and sale, Trafikverket, Borlänge. Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. Transportplanering, Royal Institute of Technology (KTH), Stockholm, Sweden. Transportplanering, Royal Institute of Technology (KTH), Stockholm, Sweden. Transportplanering, Royal Institute of Technology (KTH), Stockholm, Sweden. Systems Engineering, RISE Research Institutes of Sweden, Göteborg, Sweden. Systems Engineering, RISE Research Institutes of Sweden, Göteborg, Sweden. Department of Computer Science, Blekinge tekniska högskola, Karlskrona, Sweden. Department of Computer Science, Blekinge tekniska högskola, Karlskrona, Sweden. Transport Systems and Logistics, Lund University, Sweden. Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
Deliverable D 3.1: Analysis of the gap between daily timetable and operational traffic2019Report (Other academic)

Fr8Rail II/Work-Package 3 Real-time network management and improved methods for timetable planning addresses the problem to improve capacity and punctuality in the railway system by developing concepts and methods for tactical planning and operational traffic. In this report the state-of-the-art has been summarised.

The aim of the project is to:

• Propose concepts and methods that improve the annual and short-term timetable planning.
• Demonstrate how the proposed timetable planning concepts improve the prerequisites for real-time network management.
• Develop methods and tools that can reduce inefficiencies in real time network management.

An important aspect is to improve the coordination between yards/terminals and the line network, and between Infrastructure Manager, Yard Managers, and freight Rail Undertakings.

We motivate our research by the current situation in Sweden, which is characterised by low on-time performance for freight trains, dense and heterogenous traffic on the major railway lines, and a rigid annual timetabling process, which is non-suitable for short-term changes. We believe that better tools for network planning and management on tactical and operational level can help to connect planning and operational processes.

Aiming for improvements of the operational traffic, there is a need for systematic development of methods applied at several planning horizons, based on both simulation and optimization techniques. Close to operation fast methods are needed, for example, based on meta-heuristics.

The maintenance planning process and improvement potential have been described. This is a new piece of the puzzle and it is important to close the gap between timetable planning and operational traffic. The different planning processes at the Infrastructure Manager, the Rail Undertakings and the Maintenance Contractors should be aligned.

When developing new approaches for computational decision-support tools for real-time network management, it is important — but very challenging — to evaluate and benchmark with existing software tools. We also observe that the research stream on computational decision-support and algorithm development for railway traffic management has not yet been sufficiently merged with the corresponding research stream focusing on aspects of human computer interaction.