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  • Landström, Tomas
    Linköping University, Department of Social and Welfare Studies.
    Landström, Tomas
    Linköping University, Department of Social and Welfare Studies.
    Förutsättningarnas föreställningar: En studie om den politiska diskursen inom stadsplanering2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna studie behandlar den politiska diskursen inom stadsplanering och utveckling. Studien är baserad på kvalitativa intervjuer med politiker från kommunstyrelsen, socialnämnden och stadsplaneringsnämnden i Norrköping. Syftet är att belysa hur föreställningar inom diskursen kan utgöra förutsättningar inom stadsplaneringen. I studien kommer, bland annat, begreppen förtätning, attraktionskraft och framkomlighet lyftas fram för att belysa hur dessa kan utgöra en idémässig grund inom planeringsarbetet och belysa vilka effekter föreställningarna kan ha för stadsplanergin som politisk praktik.

  • Duhera, Indira
    et al.
    Linköping University, Department of Social and Welfare Studies.
    Duhera, Indira
    Linköping University, Department of Social and Welfare Studies.
    Makas, Arma
    Linköping University, Department of Social and Welfare Studies.
    Strukturerade sysselsättningar och fria aktiviteter vid HVB-hem: En intervjustudie om ensamkommande flyktingbarns sysselsättningar vid HVB-hem ur personalens perspektiv2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    De ensamkommande flyktingbarnen som kommer till mottagarlandet hamnar oftast på HVB-hem, inspektionen för vård och omsorg, där de får bo tills de är självständiga nog att flytta därifrån till ett eget boende. Studiens syfte är att studera hur personal på HVB-hem för ensamkommande flyktingbarn arbetar med barnens fritid. Främst för att se hur personalen arbetar  i relation till frågor som rör barns delaktighet i samband med strukturerade aktiviteter jämfört med barnens egna val av sysselsättningar. Vi har genomfört tio semistrukturerade intervjuer med personal som arbetar på HVB-hem. Utifrån personalens utsagor  så kan vi konstatera att grunden till barnens delaktighet är att personalen ska utgå ifrån varje barns enskilda behov. 

  • Björk, Teres
    et al.
    Linköping University, Department of Medical and Health Sciences.
    Björk, Teres
    Linköping University, Department of Medical and Health Sciences.
    Wahlström, Emelie
    Linköping University, Department of Medical and Health Sciences.
    "Som alla andra": Sjuksköterskors erfarenheter av att vårda personer med psykossjukdom inom somatiskvård2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Induktiv intervjustudie med syfte att beskriva vilka erfarenheter sjuksköterskor verksamma inom somatisk vård har av att vårda personer med psykossjukdom. Resultatet visar att sjuksköterskor inom den somatiska vården har relativt mycket erfarenhet av att vårda personer med psykossjukdom. Den specifika psykiatriska kompetensen uppfattades otilräcklig och vårdandet innebar ofta känslosamma möten.

  • Kozlov, Vladimir
    et al.
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Kozlov, Vladimir
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Radosavljevic, Sonja
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Turesson, Bengt Ove
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Wennergren, Uno
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering.
    Estimating effective boundaries of population growth in a variable environment2016In: Boundary Value Problems, ISSN 1687-2762, E-ISSN 1687-2770, 1-28 p., 2016:172Article in journal (Refereed)
    Abstract [en]

    We study the impact of age-structure and temporal environmental variability on the persistence of populations. We use a linear age-structured model with time-dependent vital rates. It is the same as the one presented by Chipot in (Arch. Ration. Mech. Anal. 82(1):13-25, 1983), but the assumptions on the vital rates are slightly different. Our main interest is in describing the large-time behavior of a population provided that we know its initial distribution and transient vital rates. Using upper and lower solutions for the characteristic equation, we define time-dependent upper and lower boundaries for a solution in a constant environment. Moreover, we estimate solutions for the general time-dependent case and also for a special case when the environment is changing periodically.

  • Johansson, Chrisotoffer
    et al.
    Linköping University, Department of Computer and Information Science.
    Johansson, Chrisotoffer
    Linköping University, Department of Computer and Information Science.
    Sjödin Jonsson, Martin
    Linköping University, Department of Computer and Information Science.
    Simulation of Scalable Streaming Protocols using Wireless Multicast/Broadcast2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In a society where the popularity of mobile video streaming increases, the need to understandthe affect on the power consumption on mobile devices increases. This thesislooks into which broadcasting protocol to use when trying to optimize the energy consumptionand startup delay while receiving a video from a transmitting source using scalablestreaming protocols. This thesis evaluates four different scalable streaming protocolsand how much power mobile clients consume when receiving a video over different numberof channels and how different interfaces such as 3G and WiFi affect the power consumption.The protocols are simulated using our own written simulator and a tool calledEnergyBox, which simulates both 3G and WiFi connections. The thesis also compares theprotocols with each other in two ways, the amount of energy consumed and how longthe startup delay is for each protocol. Based on these simulations and comparisons weconclude which protocol of these four provides the best energy-delay tradeoff. The resultshows that the energy consumption while usingWiFi is much less than when using 3G. FastBroadcasting is also far superior the other protocols when it comes to energy consumption.When it comes to startup delay the protocols are very even.

  • Härd, Victoria
    Linköping University, Department of Electrical Engineering, Computer Vision.
    Härd, Victoria
    Linköping University, Department of Electrical Engineering, Computer Vision.
    Automatic Alignment of 2D Cine Morphological Images Using 4D Flow MRI Data2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Cardiovascular diseases are among the most common causes of death worldwide. One of the recently developed flow analysis technique called 4D flow magnetic resonance imaging (MRI) allows an early detection of such diseases. Due to the limited resolution and contrast between blood pool and myocardium of 4D flow images, cine MR images are often used for cardiac segmentation. The delineated structures are then transferred to the 4D Flow images for cardiovascular flow analysis. Cine MR images are however acquired with multiple breath-holds, which can be challenging for some people, especially, when a cardiovascular disease is present. Consequently, unexpected breathing motion by a patient may lead to misalignments between the acquired cine MR images.

    The goal of the thesis is to test the feasibility of an automatic image registration method to correct the misalignment caused by respiratory motion in morphological 2D cine MR images by using the 4D Flow MR as the reference image. As a registration method relies on a set of optimal parameters to provide desired results, a comprehensive investigation was performed to find such parameters. Different combinations of registration parameters settings were applied on 20 datasets from both healthy volunteers and patients. The best combinations, selected on the basis of normalized cross-correlation, were evaluated using the clinical gold-standard by employing widely used geometric measures of spatial correspondence. The accuracy of the best parameters from geometric evaluation was finally validated by using simulated misalignments.

    Using a registration method consisting of only translation improved the results for both datasets from healthy volunteers and patients and the simulated misalignment data. For the datasets from healthy volunteers and patients, the registration improved the results from 0.7074 ± 0.1644 to 0.7551 ± 0.0737 in Dice index and from 1.8818 ± 0.9269 to 1.5953 ± 0.5192 for point-to-curve error. These values are a mean value for all the 20 datasets.

    The results from geometric evaluation on the data from both healthy volunteers and patients show that the developed correction method is able to improve the alignment of the cine MR images. This allows a reliable segmentation of 4D flow MR images for cardiac flow assessment.

  • Klasén, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Klasén, Erik
    Linköping University, Department of Electrical Engineering, Vehicular Systems.
    Modeling and Estimation of Long Route EGR Mass Flow in a Turbocharged Gasoline Engine2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Due to the continuous work in the automobile industry to reduce the environmental impact, reduce fuel consumption and increase efficiency, new technologies need to be developed and implemented in vehicles. For spark ignited engines, one technology that has received more attention in recent years is long route Exhaust Gas Recirculation (EGR), which means that exhaust gases after the turbine are transported back to the volume before the compressor in the air intake system of the engine. In this work, the components of the long route EGR system is modeled with mean value engine models in Simulink, and implemented in a existing Simulink engine model. Then different methods for estimating the mass flow over the long route EGR system are compared, and the transport delays for the recirculated exhaust gases in the engines air intake system are modeled. This work is based on measurements done on an engine rig, on which a long route EGR system was installed. Finally, some ideas on how a long route EGR system on a gasoline engine can be controlled are presented based on the results in this thesis work.

  • Kinner Hylén, Eva
    Linköping University, Department of Behavioural Sciences and Learning.
    Kinner Hylén, Eva
    Linköping University, Department of Behavioural Sciences and Learning.
    Från Kaos till kunskap: Unga kvinnors upplevelse av högstadietiden och gymnasiet2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta är en narrativ studie där syftet är att fånga flickors upplevelse av skolan från högstadietiden och fram i gymnasieåldern. Jag utgår från livsberättelse som metod. Mina informanter är fyra unga kvinnor som hade problematisk högstadietid men ändå lyckades att gå ett yrkesprogram på gymnasiet. Mina frågeställningar är: Hur kan de unga kvinnornas problematiska högstadietid upplevas? Hur kan kommunikationen och relationen mellan de unga kvinnorna och skolans personal upplevas? Vilka vändpunkter kan vara avgörande för att de unga kvinnorna ska uppleva att de kan fullfölja sina studier?Genom mina informanters berättelser fångade jag de avgörande vändpunkterna som gjorde att de kunde fullfölja en gymnasieutbildning. Resultatet visar att informanterna upplevde en högstadietid i kaos med stökiga lektioner, mobbning och skolk. Kommunikationen upplevdes som vertikal under högstadietiden, enligt informanterna Läraren talade till eleven, inte med eleven. Vändpunkter för informanterna var att komma till en gymnasieskola där kommunikationen upplevdes som horisontell. Informanterna ansåg att lärarna var skickliga på att se och förstå deras verklighet. Ytterligare vändpunkter var att tre av informanterna fick en diagnos. Då upplevde de unga kvinnorna en annan uppmärksamhet som ledde till bättre kommunikation. De kände sig sedda och bekräftade. Jag fann i min undersökning framför allt tre faktorer som haft stor betydelse för att lyckas med studierna och bli godkända på kurserna; inkludering, mellanmänskliga relationer och samarbete mellan skola och andra aktörer såsom sjukvård och vårdnadshavare.

  • Carlswärd, Madlene
    Linköping University, Department of Behavioural Sciences and Learning.
    Carlswärd, Madlene
    Linköping University, Department of Behavioural Sciences and Learning.
    Första läsundervisningen i årskurs 1: Hur klasslärare uppfattar och beskriver den första läsundervisningen i årskurs 1 utifrån elevers behov2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Att som klasslärare ansvara för läsundervisningen i årskurs 1 kan uppfattas som ett komplext uppdrag. Man bör ha god kunskap om läsprocessen och dess olika utvecklingsnivåer för att kunna möta eleverna där de befinner sig i läsutvecklingen, samtidigt som yttre faktorer kan påverka möjligheterna till individanpassad undervisning. Syftet med studien var att belysa hur klasslärare uppfattar elevers läsutvecklingsnivåer i årskurs 1 samt hur klasslärare beskriver sin planering och organisation av läsundervisningen utifrån elevers olika behov i årskurs 1.Lärarna i studien anser att det är lustfyllt, men också utmanande, att bedriva individanpassad läsundervisning i årskurs 1. Höga krav ställs på lärarnas kompetens när det gäller planering, genomförande och uppföljning av undervisningen. Det anses som en fördel när man uppnått en viss erfarenhet av läsinlärning och läsundervisning. Lärarna menar att kunskap om elevernas utvecklingsnivå redan vid skolstarten i årskurs 1 är mycket viktig. Förskollärarnas elevinformation till de blivande klasslärarna i årskurs 1 grundlägger planeringen av den första läsundervisningen i årskurs 1.Trygghet i skolmiljön bidrar till framgångsrik läsundervisning. Genom att eftersträva ett lärandeklimat som byggs av lek, glädje och respekt kan en trygghet i den pedagogiska miljön skapas. Det är viktigt att som klasslärare kunna inspirera och motivera eleverna till läsning. Informanterna beskriver olika arbetssätt som kan främja detta, till exempel högläsning, gruppläsning och kamratläsning.Specialläraren har en viktig roll i sammanhanget då denne bland annat ska visa fördjupad kunskap inom elevers läsutveckling, medverka i förebyggande arbete samt bidra till att avlägsna hinder och problem i undervisningsmiljön.

    Nyckelord: undervisning, läsning, tidig läsundervisning, speciallärarroll

  • Andersson, Elinor
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Andersson, Elinor
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Vad är speciellt med handledare vid klinisk undervisningsavdelning (KUA)?-En kvalitativ studie2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Supervising students in a clinical training ward (CTW) has been used for some 20 years. Studies show that interprofessional learning gives students an opportunity to get a comprehensive view of a particular patient’s health-care needs, as well as an increased and mutual understanding of their colleague’s position and knowledge. Only a few studies have focused on the supervisor’s view of his or her own role within the activity of the CTW. The purpose of the study was to describe the CTW supervisor and his or her own perception of her role as an interprofessional supervisor as well as to describe interprofessional learning on its own at the CTW. A qualitative method was used, and 19 interprofessional supervisors from and within occupational therapy, along with physicians, physiotherapists, and nurses, were interviewed.

    The texts were content-analysed. Three categories were identified: ‘the supervisor’, ‘the supervision’, and ‘the concept of CTW’. It turned out that the interprofessional supervisor has a genuine interest and commitment to supervise, to work pedagogically, to collaborate, and to work with students. The supervisors all used different strategies, and they worked with the team in focus, partly for the benefit of the students but also to show the team’s importance in relation to the patient’s health care situation. The CTW concept requires lots of time and dedication from the supervisor, but it is perceived as a good concept where students can develop interprofessional collaboration. The supervisor’s understanding and approach to student learning makes a huge difference in the process of supervision. Being an interprofessional supervisor requires a pedagogical knowledge and understanding of a group and of the group process. The student’s team knowledge influences the CTW, which affects the supervision. The concept of the CTW has a positive impact on the supervisors, and the interprofessional supervision is perceived to be stimulating and challenging.

  • Nielsen, Anders Henckel
    Linköping University, Department of Management and Engineering, Carl Malmsten - furniture studies.
    Nielsen, Anders Henckel
    Linköping University, Department of Management and Engineering, Carl Malmsten - furniture studies.
    The Man Machine: An idea about where I belong as a designer2016Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    In this project I have chosen to use my own story asa starting point. My own experiences from the projectsI have done during my time at Carl Malmsten FurnitureStudies. The purpose of this project is to get an ideaof where I belong design-wise. Analysing my ownexperiences which end up with three main elements ofthe project; Biomimicry, Stand on the shoulders ofgiants and Material and process, They have been turnedinto a tool which reflects my views on design. Themethod is based on the interaction between theanalysed and the practically executed. In order forme as a designer to understand what I do, I have toactually do it, or experience it.

  • Mohsen, Thaer
    Linköping University, Department of Behavioural Sciences and Learning.
    Mohsen, Thaer
    Linköping University, Department of Behavioural Sciences and Learning.
    De bryter upp och börjar om: – Invandrade kvinnors deltagande i svenska som andra språk2016Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med studien är att utifrån invandrade kvinnors utsagor utröna förståelse för hur de upplever sina studier i Svenska som andraspråk samt finna förståelse för deras identitetsformering. Studien har genomförts med en kvalitativ metod i form av intervjuer. Forskningsfrågorna behandlar kvinnornas drivkrafter, motivation, sociala och kulturella bakgrund samt balans mellan studier och vardagsliv. Studien som har ett genusperspektiv visar att kvinnorna inte är omedvetna om sin underordnade roll, som kvinnor och som invandrare samt den stereotypa synen på dem som bärare av problemegenskaper. De uttrycker att deltagandet i studierna och den form av socialisation som sker i skolmiljön öppnar nya vyer för dem och är den nyckel som öppnar dörrar till de yrken de önskar arbeta inom. Kvinnorna är tydliga med att studierna är ett avstamp mot en friare och rörligare social roll, både hemma och i samhället t.ex. kontakter med offentliga institutioner. Kvinnornas verkliga drivkrafter, det som motiverar dem, är en framtidsvision.  

    De yngre identifierar sig tydligt med det nya samhällets normer om jämlikhet och jämställdhet samt bevarar de delar som de identifierar sig med i sina egna kulturer. Den något äldre generationen av kvinnor som har bildat familj håller tillbaka sin sociala roll och förhandlar fram nya möjligheter för brytning med det gamla mot en början på en ny identitetformering.

    För bägge generationerna är studierna ett stort steg mot större medvetenhet om sin aktiva roll i samhället.

    Resultatet av studien öppnar för nya områden att söka kunskap om.

    Vilka förutsättningar till integration ger skolan för invandrade kvinnor med låg eller ingen tidigare skolgång?

    Hur ser skolan på kvinnornas studier och identitetsutveckling utifrån ett sociokulturellt perspektiv på lärandet?

  • Public defence: 2016-10-21 10:15 Plank, Fysikhuset, Linköping
    Fashandi, Hossein
    Linköping University, Department of Physics, Chemistry and Biology, Applied Sensor Science. Linköping University, Faculty of Science & Engineering.
    Fashandi, Hossein
    Linköping University, Department of Physics, Chemistry and Biology, Applied Sensor Science. Linköping University, Faculty of Science & Engineering.
    Novel Layered and 2D Materials for Functionality Enhancement of Contacts and Gas Sensors2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Chemical gas sensors are widely-used electronic devices for detecting or measuring the density levels of desired gas species. In this study, materials with established or potential applications for gas sensors are treated. For the case of high-temperature applications (≈ 600 °C), semiconductor-based gas sensors suffer from rapid oxidation of the metallic ohmic contacts, the same cause-of-failure as for the general case of high-temperature semiconductor electronics. 4H-SiC is an ideal semiconductor for high-temperature applications. Ti3SiC2 is a known ohmic contact to 4H-SiC with the known two-step synthesis process of post-annealing of pre-deposited Ti/Al multilayers or sputter-deposition of Ti3SiC2 films at > 900 °C. Here, sputter-deposition of Ti on 4H-SiC at > 900 °C is presented as a novel single-step method for the synthesis of Ti3SiC2 ohmic contacts, based on a concurrent reaction between sputter-deposited Ti and 4HSiC. Ti3SiC2, similar to any other known ohmic contact, degrade rapidly in high-temperature oxidizing ambient. To try to overcome this obstacle, noble metal diffusion into Ti3SiC2 has been s studied with the goal to retain ohmic properties of Ti3SiC2 and harnessing oxidation resistivity of noble metals. A novel exchange intercalation between Ti3SiC2 and Au is discovered which results in the almost complete exchange of Si with Au giving rise to novel Ti3AuC2 and Ti3Au2C2. Ti3IrC2 is also synthesized through exchange intercalation of Ir into Ti3Au2C2. All the aforementioned phases showed ohmic properties to 4H-SiC. This technique is also studied based on Ti2AlC and Ti3AlC2 resulting in the synthesis of novel Ti2Au2C and Ti3Au2C2, respectively. Using Ti3AuC2 and an Au/IrOx capping layer, an ohmic contact was manufactured, which maintained ohmic properties and showed no structural defects after 1000 h of aging at 600 °C air.

    Ti3SiC2 is a member of a large family of materials known as Mn+1AXn phases. While exchange reactions of Si (or Al) planes in Ti3SiC2 (Ti2AlC and Ti3AlC2) is presented here, a world-wide research already exists on chemical removal of the same atomic planes from different Mn+1AXn phases and the synthesis of Mn+1Xn sheets known as MXenes. I performed a theoretical study regarding simulation of electronic and structural properties of more than120 different possible MXene phases. The results show that some MXene phases, when terminated by particular gas species, turn into Dirac materials. That is, they possess massless Dirac fermions with different properties compared to graphene such as higher number of Dirac points at the Fermi level, giant spin orbit splitting, and preserved 2D-type electronic properties by extending the dimensionality. The general substantial change of the electronic properties of MXenes under different gas adsorption configurations stands out and can thus be harnessed for sensing applications.

    Growth of monolayer iron oxide on porous Pt sensing layers is another novel approach used in this study for applying the unique properties of 2D materials for gas sensors. A low temperature shift in CO oxidation characteristics is presented. The approach is similar to that previously reported using bulk single crystal Pt substrate, the latter being an unrealistic model for sensors and catalysts. Monolayer-coated Pt sensing layers were fabricated as the metal component of a metal oxide semiconductor (MOS) capacitor device, whereby the electrical response of the MOS device could be used to map out the catalytic properties of the sensing layer. The monolayer-coated Pt surface showed to be stable with retained improved catalytic properties for > 200 h. The MOS device measurements are here utilized as a handy method for in-situ monitoring of the surface chemical properties of the monolayer-coated Pt and the approach is highly functional for use and characterization of monolayer coatings of widely used sensingor catalytic layers.

    List of papers
    1. Single-step synthesis process of Ti3SiC2 ohmic contacts on 4H-SiC by sputter-deposition of Ti
    Open this publication in new window or tab >>Single-step synthesis process of Ti3SiC2 ohmic contacts on 4H-SiC by sputter-deposition of Ti
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    2015 (English)In: Scripta Materialia, ISSN 1359-6462, E-ISSN 1872-8456, Vol. 99, 53-56 p.Article in journal (Refereed) Published
    Abstract [en]

    We report a single-step procedure for growth of ohmic Ti3SiC2 on 4H-SiC by sputter-deposition of Ti at 960 °C, based on the Ti–SiC solid-state reaction during deposition. X-ray diffraction and electron microscopy show the growth of interfacial Ti3SiC2. The as-deposited contacts are ohmic, in contrast to multistep processes with deposition followed by rapid thermal annealing. This procedure also offers the possibility of direct synthesis of oxygen-barrier capping layers before exposure to air, potentially improving contact stability in high-temperature and high-power devices.

    Place, publisher, year, edition, pages
    Elsevier, 2015
    Keyword
    Silicon carbide, MAX phase, Physical vapor deposition, High temperature
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-113760 (URN)10.1016/j.scriptamat.2014.11.025 (DOI)000348881100014 ()
    Note

    We acknowledge the support from the VINN Excellence Center in research and innovation on Functional Nanoscale Materials (FunMat) by the Swedish Governmental Agency for Innovation Systems. P.E and J.L. also acknowledge support from the Swedish Foundation for Strategic Research through the Future Research Leaders 5 program and the Synergy Grant FUNCASE, Functional Carbides and Advanced Surface Engineering. In addition, we thank Dr. Hans Hogberg, Dr. Arni Sigurdur Ingason and Dr. Fredrik Eriksson for discussions and help with experiments.

    Available from: 2015-01-30 Created: 2015-01-30 Last updated: 2016-09-22Bibliographically approved
    2. Dirac points with giant spin-orbit splitting in the electronic structure of two-dimensional transition-metal carbides
    Open this publication in new window or tab >>Dirac points with giant spin-orbit splitting in the electronic structure of two-dimensional transition-metal carbides
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    2015 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 92, no 15Article in journal (Refereed) Published
    Abstract [en]

    We investigated the structural and electrical properties of 2D MXene sheets by means of firstprinciples density functional theory (DFT) calculations. To describe the Kohn-Sham states, plane wave basis set and projector augmented wave method (PAW) were used as implemented in the Vienna ab initio Simulation Package (VASP). We applied PBE parameterization of the generalized gradient approximation of the exchange and correlation energy functional to account for many-body effects of the interacting electron system. Convergent sampling of the Brillouin-zone was achieved by a Γ-centered 15×15×1 grid. In order to model a single sheet of MXene we ensured at least 30 Å vacuum between the periodically repeated sheets. For the structural optimization 1×10−3 eV/Å force criteria was used. The relativistic spin-orbit coupling effects were also included in our simulations regarding band structure and density of states.

    Keyword
    Cone-point, MAX phase, MXene, Dirac fermion, Spin-orbit coupling
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:liu:diva-113761 (URN)10.1103/PhysRevB.92.155142 (DOI)000363512700002 ()
    Available from: 2015-05-01 Created: 2015-01-30 Last updated: 2016-09-22Bibliographically approved
  • Hamsis, Omar
    Linköping University, Department of Computer and Information Science.
    Hamsis, Omar
    Linköping University, Department of Computer and Information Science.
    Flattened hierarchal interface in a Geographical Information System: Designing a system for creating and preparing maps for aviation2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    GIS have been plagued by complicated interfaces for some time but is improving. This thesis researches whether an interface with a flattened hierarchy is better suited for a geographical information system rather than a ribbon interface. Two interfaces were built for a system used to supply geographical data to aircraft and Mission support systems. A pre-study was conducted with the existing users and developers to synthesize initial requirements and conclude what is troublesome in the existing system and the workflow process. It was found that there was a lack of consistency in the current system and that the workflow felt ad-hoc. Two prototypes were developed as add-in in Esri’s newly launched ArcGIS Pro and usability tested, one using the ribbon interface and one with the flattened hierarchal interface. Using the subjective workload NASA TLX questionnaire, time on task and a questionnaire regarding the participants’ attitude towards the interface, it was able to see how the workload, efficiency and attitude for the different interfaces were. The usability testing of these interfaces showed no significant difference in time. There was only one significantly difference for the workload, it was in the physical scale. Users that first tested the ribbon interface and later the flattened hierarchal interface found the second interface to be significantly more demanding physically. An attitude questionnaire showed also that participants felt that the flattened hierarchal interface was significantly more overwhelming and would be more discouraged to use it compared to a ribbon interface.

  • Benjamin, Andersson
    Linköping University, Department of Computer and Information Science, Software and Systems.
    Benjamin, Andersson
    Linköping University, Department of Computer and Information Science, Software and Systems.
    En teoretisk och praktisk jämförelse av alternativ till OpenLayers2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Med att de mobila enheterna blir allt mer kraftigare och webbtekniken går allt fortare framåt, så har webbapplikationer börjat blivit ett fullgott alternativ till vanliga nativeapplikationer. Presentera webbkartor med hjälp av ramverket OpenLayers har aldrig varit en större användarupplevelse på  mobil enhet då det är både stort och tungkört för en segare enhet. Samt att de aldrig var tänkte från början att fungera för  touchbaserade enheter, utan de är stöd som  senare har lagts på.

    Därför har jag hittat ett annat fullgott  alternativ till OpenLayers som heter Leaflet, som är anpassat att ha alla funktioner som  man kan kräva av en webbaserad karta och samtidigt fungera i mobila touch enheteter. Leaflet använder alla nya webbtekniker som HTML5 och CSS3 i största möjliga mån för att få sådan bra upplevelse som möjligt.

    Jag gjorde om hela klientdelen av en realtidskarta för blixtar i Leaflet istället, så att den skulle fungera bättre på en mobil enhet än vad den tidigare gjorde. Med denna implementation så visade sig att Leaflet kunde nå upp till alla krav som man kan ställa på en webbaserad karta. Resultatet blev en mycket lättare och snabbare klient med samma funktionalitet som den förra hade.

  • Ericson, Niklas
    Linköping University, Department of Electrical Engineering, Automatic Control.
    Ericson, Niklas
    Linköping University, Department of Electrical Engineering, Automatic Control.
    Investigation of Control Approaches for a High Precision, Piezo-Actuated Rotational Stage2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Equipment Controls and Electronics section (EN-STI-ECE) at CERN is developing a high precision piezo-actuated rotational stage for the UA9 crystal collimation project. This collaboration is investigating how tiny bent crystals can help to steer particle beams used in modern hadron colliders such as the Large Hadron Collider (LHC). Particles are deflected by following the crystal planar channels, "channeling" through the crystal. For high energy particles the angular acceptance for channeling is very low, demanding for a high angular precision mechanism, i.e. the rotational stage. Several control-related issues arising from the complexity and operational environment of the system make it difficult to design a controller that achieves the desired performance. This thesis investigates different control approaches that could be used to improve the tracking capability of the rotational stage. It shows that the IRC method could be used to efficiently control the rotational stage. Moreover it shows that a harmonic cancellation method could be used to increase the tracking accuracy by canceling known harmonic disturbances. The harmonic cancellation method (the RFDC) was implemented in this thesis and proposed as an add-on to the present control algorithm.

  • Grankvist, Ola
    Linköping University, Department of Electrical Engineering, Computer Vision.
    Grankvist, Ola
    Linköping University, Department of Electrical Engineering, Computer Vision.
    Recognition and Registration of 3D Models in Depth Sensor Data2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Object Recognition is the art of localizing predefined objects in image sensor data. In this thesis a depth sensor was used which has the benefit that the 3D pose of the object can be estimated. This has applications in e.g. automatic manufacturing, where a robot picks up parts or tools with a robot arm.

    This master thesis presents an implementation and an evaluation of a system for object recognition of 3D models in depth sensor data. The system uses several depth images rendered from a 3D model and describes their characteristics using so-called feature descriptors. These are then matched with the descriptors of a scene depth image to find the 3D pose of the model in the scene. The pose estimate is then refined iteratively using a registration method. Different descriptors and registration methods are investigated.

    One of the main contributions of this thesis is that it compares two different types of descriptors, local and global, which has seen little attention in research. This is done for two different scene scenarios, and for different types of objects and depth sensors. The evaluation shows that global descriptors are fast and robust for objects with a smooth visible surface whereas the local descriptors perform better for larger objects in clutter and occlusion. This thesis also presents a novel global descriptor, the CESF, which is observed to be more robust than other global descriptors. As for the registration methods, the ICP is shown to perform most accurately and ICP point-to-plane more robust.

  • Strand, Benjamin
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    Strand, Benjamin
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    En skildring av vad som bör gälla vid köp av lösöre; den ålderstigna traditionsprincipen eller den gryende avtalsprincipen2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    I denna uppsats har jag fördjupat mig i det sakrättsliga rättsområdet , närmare bestämt de två rättsprinciper som är avgörande vid uppkomsten av sakrättsligt skydd; traditionsprincipen och avtalsprincipen. Det har under längre tid pågått en diskussion angående vilken rättsprincip som bör vara gällande rätt vid köp av lösöre i svensk rätt. Idag är traditionsprincipen gällande rätt och har varit det under lång tid. I denna uppsats har en genomgång av det sakrättsliga området gjorts och jag har kommit till slutsatsen att avtalsprincipen bör ersätta traditionsprincipen vid köp av lösöre.

    Uppsatsen riktar sig till såväl personer med juridiska kunskaper som personer utan. Uppsatsen är skriven för belysa den problematik som föreligger inom rättsläget vid köp av lösöre i Sverige. Utöver belysa problemet i den svenska rätten har jag även föreslagit en förändraring av det svenska rättsläget.

    En historisk redogörelse av rättsområdet har gjorts i den inledande delen av uppsatsen. Efter den rättshistoriska delen har en redogörelse för traditionsprincipen, innehållande en grundlig rättsfallsanalys, gjorts. Efter traditionsprincipen har en liknande skildring för avtalsprincipen gjorts.

    En genomgång av de argument som diskuterats i artiklar, doktrin, och rättsfall, för och emot såväl traditionsprincipen som avtalsprincipen har tagits upp och behandlats i uppsatsen.

    Avslutningsvis har en analys av all framlagd fakta gjorts där min slutsats, att det föreligger övervägande skäl för en övergång till avtalsprincipen vid köp av lösöre, har presenterats.

  • Jorikson, Lovisa
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    Jorikson, Lovisa
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    Tidsgränser för ramavtal och avropsavtal: Reglerna inom klassiska sektorn2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Upphandlingsinstrumentet ramavtal används i stor utsträckning i såväl Sverige som i övriga EU-länder. Vid upphandling av ramavtal måste inblandade parter beakta de bestämmelser som syftar till att upprätthålla sund konkurrens på marknaden. Svensk upphandlingsrätt har sin grund i EU-rätten och de upphandlingsprinciper som framkommit genom EU-praxis på området. De svenska lagarna LUF och LOU bygger på två EU-direktiv.Upphandlingsrätten har en nära koppling till konkurrensrätten. Eftersom det rör sig om stora och många gånger gränsöverskridande affärer, som påverkar den inre marknaden, är det en förutsättning att en effektiv konkurrens upprätthålls. De grundläggande EU-rättsliga principerna ska iakttas genom hela upphandlingsförfarandet, oavsett vilken upphandling det rör sig om. Genom all upphandling måste hänsyn tas till vilka effekter affären kan ha på konkurrensen.Ramavtal inom klassiska sektorn får som huvudregel ingås för en period om fyra år. I undantagsfall får tiden vara längre men då krävs att upphandlande myndighet visar att omständigheterna i det enskilda fallet är av sådan beskaffenhet att en längre tid är nödvändig och inte påverkar konkurrensen på ett otillbörligt sätt. Det måste enligt LOU föreligga särskilda skäl för en längre avtalstid. Situationen kan ibland även vara den motsatta på så sätt att en längre tid än fyra år är nödvändig ur konkurrenshänseende.Avropsavtal som tilldelas utifrån ramavtal lyder inte under någon egen tidsbestämmelse, varken i EU-direktiven från år 2004 eller i de svenska upphandlingslagarna. Det framgår av kommissionens tolkningsmeddelande för ramavtal, likt framträdande doktrin, att avropsavtalen per automatik följer av ramavtals tidsbestämmelser. I praxis och framförallt skältexten till nya direktivet framkommer att avropsavtalen inte nödvändigtvis måste överensstämma med ramavtalstiden.De oklarheter som avsaknaden av bestämmelser medför torde kunna avhjälpas genom vägledande domstolsavgöranden eller klarare regler gällande ramavtal, och specifikt avropsavtal. Det är uppenbart att avropsavtal inte får löpa på obegränsad tid för att syftet med ramavtal ska upprätthållas. Det är däremot svårt att se vilka bestämmelser som är lämpliga då omständigheterna skiljer sig åt väsentligt i varje enskilt fall. Av utredningen framgår att rättsläget är oklart och skapar frågetecken och svårigheter i ramavtalsupphandlingar, särskilt vad gäller de som kräver en längre avtalstid än normalt.

  • Näslund, Johan
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Näslund, JohanLinköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Psykolognyttadel 2. Chefer och handledare om nyttan medpsykologutbildningen vid Linköpings universitet: En utvärdering av psykologprogrammet vid Linköping universitet. Genomfört av psykologstudenter termin 8 vid Linköpings universitet under vårterminen 2009.2010Collection (editor) (Other academic)
    Abstract [sv]

    Sammanfattningsvis kan man beskriva denna litteraturstudie som en kort genomgång av ett sätt att resonera vid utvärdering av högskolor i synnerhet men som förhoppningsvis även är användbar på ett generellt plan. Frågan ”vad måste vi tänka på i en utvärdering av ett högskoleprogram” kan anses delvis besvarad då ett fullständigt svar på denna komplexa fråga bland annat skulle behöva ett större utrymme för teorigenomgång av fler modeller och tankesätt. Dock är det en grund som väl tar läsaren genom ett systematiskt tillvägagångssätt för kritisk utvärderingsbedömning. Vi har förstått att det finns så väl kvalitativa som kvantitativa metoder att tillgå och att det är viktigt att valet av metod är relaterat till syfte och målgrupp, inte minst för att utvärderingen ska bli valid och användbar.

    Man kan även skönja att den etiska problematiken vid utvärderingar är en viktig och svår faktor att ta i beräkning. Etikfrågan är en viktig aspekt i alla delmoment av en utvärdering från ”varför” till ”resultat” och vi vet nu att det ofta finns en diskrepans i beställarens deklarerade avsikt och utvärderingens användning varför detta måste tas i beaktande så tidigt som vid förankringen hos de medverkande och så sent som vid rapportskrivningen.

    Förhoppningsvis har denna litteraturstudie inspirerat läsaren och öppnat upp ett forum för diskussion och eftertanke gällande vad utvärderingar av högskolor och andra instanser kan föra med sig i form av positiva och negativa åtgärder. Kanske kan litteraturstudien av utvärderingsverktyget underlätta för läsaren vid hennes nästa analys av en utvärdering.

  • Näslund, Johan
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Näslund, JohanLinköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Psykolognytta. Psykologer om nyttan med sin psykologutbildning vid Linköpings universitet: En utvärdering av psykologprogrammet vid Linköping universitet. Genomfört av psykologstudenter termin 8 vid Linköpings universitet under höstterminen 20082009Collection (editor) (Other academic)
    Abstract [sv]

    Denna studie hade när undersökningarna startade ett dubbelt syfte; att i studiesyfte lära sig hur man gör en utvärdering och utifrån uppdragsgivarens syfte, dvs psykologutbildningen vid Linköpings universitet, få indikationer på vilken nytta utbildningen har fyllt för de psykologer som utbildats vid Linköpings universitet. Utvärderingen är uppdelad i tre delar med en inledande litteraturstudie och därefter en enkätstudie och en intervjustudie av leg psykologer som gått sin utbildning vid Linköpings universitet. Studenternas texter har behållits i rapporten förutom några kommentarer som är inlagda för att förklara sammanhang.

    Vi kan sammanfattningsvis i enkätdelen konstatera att de svarande i huvudsak rapporterar att de är nöjda med sin psykologutbildning vid Linköpings universitet; 88,5% svarar som tidigare nämnts att de är "Ganska nöjda" eller "Mycket nöjda". Detta är ett resultat som återspeglas i såväl utvärderingen från Högskoleverket (2004) som från Synovates Nöjd- Student-Index (2008), vilka har vänt sig till studenter under pågående utbildning. Detta skulle kunna vara ett tecken på att utbildningen helt enkelt håller god kvalitet, och att mycket i programplanen med trygghet kan bevaras. Det vore intressant att jämföra siffrorna för hur många som skulle rekommendera psykologprogrammet vid Linköpings universitet till en vän med motsvarande siffror för andra orter. Att endast 1,8 % av respondenterna inte skulle göra det tycker vi är ett mycket bra betyg som är värt att marknadsföra.

    Det finnas skilda bilder de intervjuade har av sin utbildning i efterhand, vilket skulle kunna spegla individernas olikheter, men kanske också att de har läst ett föränderligt psykologprogram vid olika tidpunkter och att detta skulle kunna ha lett till att de har mycket olika upplevelser av programmet. Olika berättelser speglar olika delar av utbildningen vid olika tidpunkter. De som deltagit i intervjuerna beskriver en utbildning där det stundom blåst mycket hårt och stundom hägrat ett relativt lugn.

  • Nielsen, Jan
    et al.
    Nielsen, Jan
    Näslund, Johan
    Linköping University, Department of Behavioural Sciences. Linköping University, Faculty of Arts and Sciences.
    Introduktion til temanummer om supervision2005In: Matrix, ISSN 0109-646X, E-ISSN 2387-600X, Vol. 22, no 4, 305-308 p.Article in journal (Other academic)
    Abstract [no]

    I dette temanummer af Matrix om supervision vil læseren blive præsenteret for 8 artikler, der dækker et bredt og varieret felt, som fx lære- og udviklingsforløb, supervisionsprocesser, metoder og formater, samt konteksternes betydning. Vi har forsøgt at præsentere artiklerne, så de kommer til at tegne et stadigt bredere perspektiv.

  • Jakobsson, Samantha
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    Jakobsson, Samantha
    Linköping University, Department of Management and Engineering, Commercial and Business Law.
    Skäl för avbrytandebeslut inom offentlig upphandling: Tillämpning och legala risker2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Att en upphandlande myndighet väljer att avbryta en upphandling är inte ovanligt. Skälen varför en myndighet väljer att göra det är mycket varierande. Möjligheten för en upphandlande myndighet att avbryta en pågående upphandling finns dock inte stadgat i OU eller i bakomliggande direktiv. Enligt rättspraxis på området krävs att det föreligger sakligt godtagbara skäl för att en upphandling ska kunna avbrytas. Ett av syftena med framställningen är att försöka s kapa en klarhet i när sakligt godtagbara skäl anses föreligga och inte. Genom att studera både EU-praxis och svensk rättspraxis kan det konstateras att domstolarna i vissa fall, som vid bristande konkurrens, är enhälliga om att sakligt godtagbara skäl föreligger. I andra fall, t.ex. vid tidsbrist, kommer domstolar fram till olika domslut vilket tyder på att omständigheter i enskilda fall är av avgörande betydelse. Det är också svårt att dra några klara slutsatser från de rättsfall där sakligt godtagbara skäl inte ansetts föreligga. Vad som står i förfrågningsunderlaget angående avbrytande av upphandlingen synes inte spela någon roll vid bedömningen om sakligt godtagbara skäl föreligger eller inte. Det är inte heller lättare för en myndighet att avbryta en upphandling om skälen härför angetts i förfrågningsunderlaget eftersom domstolarna inte synes lägga någon vikt på om det står något om avbrytande i förfrågningsunderlaget.

    Ett avbrytande av en upphandling medför en del risker som både leverantörer och myndigheter måste tänka på. De största rättsliga riskerna som föreligger är att en upphandlande myndighet, under en pågående överprövning, startar ett nytt upphandlingsförfarande som avser samma upphandlingsföremål eller ingår ett avtal med en leverantör. Vad som händer i situationer som dessa är inte helt klart och nya frågor uppstår istället.

    Det finns skäl för ändringar vad gäller möjligheten att avbryta en upphandling och de rättsliga möjligheterna för leverantörer att tillvarata sin rätt när så sker. Självklart ska upphandlande  myndigheter kunna avbryta upphandlingar om det finns en risk att de inte kommer att kunna slutföra upphandlingen på ett tillfredställande sätt. Jag är dock av åsikten att vissa grunder för när ett sakligt godtagbart skäl föreligger tillämpas alltför strikt. Tillräcklig hänsyn tas inte till leverantörers intresse av att upphandlingen fortskrider.

  • Näslund, Johan
    Linköping University, Department of Behavioural Sciences. Linköping University, Faculty of Arts and Sciences.
    Näslund, Johan
    Linköping University, Department of Behavioural Sciences. Linköping University, Faculty of Arts and Sciences.
    Kartläggning av vuxna missbrukare i Nässjö kommun, hösten 1999: Socialtjänsten i Eksjö kommun Mars 20002000Report (Other academic)
    Abstract [sv]

    Undersökning är gjord på uppdrag av socialförvaltningen i Nässjö kommun. Syftet med undersökningen är att skapa ett realistiskt underlag för förebyggande och behandlande insatser inom missbrukarvården. Sättet att göra undersökningen på, den s.k. fallsökningsmetoden, är prövad av Centralförbundet för Alkohol och Narkotikaupplysning (CAN) och Folkhälsoinstitutet i de s.k. UNOundersökningarna 1979 och 1992 samt i undersökningar gjorda i Stockholm 1995, Linköping 1996, Uppsala 1997 och Jönköping 1998.

    Som vetenskaplig konsult och handledare har Johan Näslund, Institutionen för beteendevetenskap och socialt arbete Hälsohögskolan i Jönköping, fungerat. Från socialförvaltningens sida har Thorbjörn Ahlgren arbetat med undersökningen. Rapporten är skriven efter preliminär redovisning för sociala nämndens ledamöter och socialförvaltningens chefer i Nässjö kommun. Under arbetets gång har material från andra liknande undersökningar tagits fram.

    Etisk granskning av projektet har skett av Bo Pettersson, Linköpings universitet och medlem av Humanistiskt Samhällsvetenskapliga Forsknings Rådet (HSFR) etiska kommitté. I samband med dessa diskussioner har kontakt tagits med jurister på Nässjö kommuns centrala förvaltning om den tystnadsplikt som gäller för Johan Näslund och Thorbjörn Ahlgren, även gentemot kommunens egna förvaltningar. Vid diskussioner med Bo Pettersson framkom att det finns två etiskt känsliga grupper i undersökningen; missbrukarna (studieobjekten) och informanterna (informationsgivarna). Undersökningen har därför genomförts anonymt, utan att veta vilka informanterna är, och studieobjektens anonymitet har garanterats på sedvanligt vetenskapligt sätt.

    Enkäten tillsammans med följebrev (se bilaga) har distribuerats till statliga, landstingskommunala, kommunala, privata enheter och institutioner samt frivilliga organisationer, som har med missbrukare i Nässjö kommun att göra. I samband med distributionen har inbjudits till informationsmöten. Ifyllda enkäter har skickats till Johan Näslund på Hälsohögskolan som fört över åldersgrupp och kön till enkätens andra sida som sedan använts vid databearbetning. Första sidan har därefter förstörts. Andra sidan på enkäterna betraktas som vetenskapligt material och finns arkiverat i därför avsett låst utrymme.

    Vad som menas med missbruk i denna undersökningen har definierats enligt följande: Med missbruk avses bruk av alkohol och/eller droger som klart påverkar den dagliga situationen.

  • Näslund, Johan
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Näslund, Johan
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Projekt Arbetskraft: utvärdering av ett arbetsmarknadsprojekt i Gnosjö kommun2008Report (Other academic)
    Abstract [sv]

    Projekt arbetskraft ska ”slussa in personer som i dag står utanför arbetsmarknaden till stimulerande och reella arbetstillfällen på den ordinarie arbetsmarknaden i Gnosjö kommun med omnejd” (från ansökan till EFS-råd). Målet har varit att 90 procent av deltagarna ska ha en konkret individuell handlingsplan och 70 procent av deltagarna ska finnas i arbete eller studier efter deltagande i projektet. Deltagarna söktes i första hand bland dem som stått utanför arbetsmarknaden under en lång tid och flera antogs vara icke nordiska invandrare. Personerna antogs ha svårigheter att etablera/återetablera sig pga. ”nedsatt arbetsförmåga, ensidig eller ingen adekvat yrkeserfarenhet, språkliga arbetshinder eller långtidssjukskrivning”.

    Projekt arbetskraft i Gnosjö åren 2006-2007 kan på flera sätt sägas uppfylla sina målsättningar. Deltagarna och samordnarna är överlag positiva och anser att projektet har haft en viktig funktion att fylla när det gäller deltagarnas återgång i arbete eller utbildning.

    Samarbetet inom projektet har fungerat väl och man har i stort sett de förväntade problem som man utifrån erfarenheter av andra projekt kan se. Sidoeffekter som ökat självförtroende och en större social förmåga stämmer väl med andras åsikter om att när människor kommer tillsammans med likartade problem ökar den sociala förmågan och självförtroendet.

    Det största frågetecknet i utvärderingssammanhang som denna rör dock en fråga som vi inte kan svara på; vilken inverkan har projektet på sikt för att deltagarna ska återgå till arbete eller utbildning? Denna utvärdering kan liksom andra liknande utvärderingar endast se till det korta perspektivet.

  • Näslund, Johan
    Linköping University, Department of Education and Psychology. Linköping University, Faculty of Arts and Sciences.
    Näslund, Johan
    Linköping University, Department of Education and Psychology. Linköping University, Faculty of Arts and Sciences.
    Jönköpings Psykiatriska Institutioner i ett medicinhistoriskt perspektiv1988Report (Other academic)
  • Näslund, Johan
    et al.
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Näslund, Johan
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Lundgren, Susanne
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Resursskolan Greppet i Värnamo: En utvärdering2015Report (Other academic)
    Abstract [sv]

    Sammanfattningsvis kan sägas att pojkarnas samlade intryck av tiden på Greppet är positivt där personalen uppfattas som både föräldrar och kompisar. När man fick tillit till personalen kom självrespekten och respekten för flera vuxna. När självkänslan och självrespekten stärktes kom tankar på framtiden och på sitt eget bästa.

    Att man fått arbeta i en liten grupp har bidragit till en ökad förmåga att behålla koncentrationen och därmed kunna slutföra och tillgodogöra sig sina skolämnen. Innehållsmässigt är lektioner, arbetet, aktiviteter och utflykter med personalen viktiga för välbefinnandet och för att behålla motivationen för att få ihop poäng för att kunna söka till gymnasiet. Upplägget på skolan med en kombination av arbete och undervisning upplevs som mycket positivt och stärkande för självkänslan och självförtroendet. Pojkarna uttrycker att de ökat sin förmåga att kommunicera tydligare där man kan tala om vad man tycker och vill. Genom de grupprocesserna som verkar och som speciellt blir påtagliga i en liten grupp så berättar i stort sett samtliga pojkar att de blivit bättre på att fungera i grupp. Man visar större hänsyn men man värnar också mera om sin integritet och klarar idag av att sätta gränser i större utsträckning. Därmed klarar man oftare av att säga nej till droger och skolk.

    Utvärderingen visar att verksamheten på Resursskolan Greppet stämmer överens med den målsättning och det arbetssätt som finns beskriven för enheten under tiden som pojkarna befinner sig i verksamheten. Problematiken ligger i vad som händer efter Greppet. Som forskningen visar är det viktigt att även i fortsättningen, efter Greppet, sätta in stödåtgärder som bygger vidare på Greppets arbete. Här kan vi se att under den korta tid som pojkarna tillbringar på Greppet inte finns förutsättningar att mer varaktigt få framgångarna på Greppet att fungera i andra sammanhang. De nära relationerna mellan pojkarna och personalen är en förutsättning för arbetet på Greppet. Detta kan dock skapa problem för pojkarna i det att de inte vill lämna Greppets ”trygga famn”. En ambivalens som är vanlig i denna typ av verksamhet.

  • Ahlgren, Thorbjörn
    et al.
    Luppen kunskapscentrum.
    Ahlgren, Thorbjörn
    Luppen kunskapscentrum.
    Näslund, Johan
    Linköping University, Department of Behavioural Sciences. Linköping University, Faculty of Arts and Sciences.
    Kartläggning av barn i behov av stöd år 2002: Eksjö kommun2003Report (Other academic)
    Abstract [sv]

    Följande rapport bygger på enkätsvar från olika myndigheter i Eksjö kommun som har rapporterat de barn/ungdomar i åldern 0-18 år som man i sin verksamhet kommer i kontakt med och som man känner oro för, p.g.a. en ogynnsam utveckling. Tjugo förutbestämda kriterier användes för att beskriva orsaken till myndighetens oro. Myndigheterna har också rapporterat om de insatser som görs redan idag samt om man bedömer att det kan bli aktuellt med ytterligare insatser nu eller i framtiden.

    Totalt inrapporterades 842 barn och ungdomar. Socialförvaltningen rapporterade 78 barn och ungdomar, Barnavårdscentralen 30 barn och skolan 689 barn och ungdomar. Av 45 enkätsvar framgår det inte vem som är rapportör. Vid bearbetningen av insamlat material har 10 enkätsvar uteslutits eftersom de inte var tillräckligt ifyllda. 103 enkätsvar uteslöt för att de flerrapporterade barn och/eller ungdomar och 17 enkätsvar uteslöts eftersom de rapporterade ungdomar som inte är skrivna i Eksjö kommun. Slutligen kom 712 barn och ungdomar att ingå i kartläggningen. Detta är drygt 18,8 % av alla aktuella barn och ungdomar. Av dessa är en klar majoritet pojkar (446 dvs. 62,6 %). För hela målgruppen främst tre huvudorsaker som ger anledning till oro hos berörda myndigheter. Det är;

    1. Föräldrarna brister i omsorgen, i stödet till den unge eller möjligheten att ge stimulans pågrund av sociala, mentala, fysiska eller psykiska handikapp och/eller missbruksproblem. För130 (av 712) barn och ungdomar anser man att det är huvudorsaken till oro.
    2. Barn/ungdomar som är introverta (tysta, blyga, nedstämda, mutister). För 69 av (712) barnoch ungdomar är det huvudorsaken till att man känner oro.
    3. Föräldrars separation eller ständiga konflikter påverkar den unge negativt. För 66 av (712)barn och ungdomar är det huvudorsaken till att man känner oro.

    Resultatredovisningen visar att skolan är den myndighet vars insatser dominerande är det också så att olika insatser inom skolan dominerar. Vanligast är undervisning i liten grupp och olika typer av specialundervisning. Olika typer av anpassad studiegång är också en vanlig insats att möta barn och ungdomar med olika svårigheter. Även olika psykosociala åtgärder förekommer också t.ex. stödsamtal med skolsköterska eller kurator. Vanligast av socialförvaltningens insatser är kontaktperson/familj.

    Berörda myndigheter uppmanas också att föreslå olika typer av nya insatser för de rapporterade barnen och ungdomarna. Även här dominerar olika typer av skolinriktade insatser. Vanliga förslag är undervisning i liten grupp och/eller olika typer av specialundervisning. När socialförvaltningen anses vara ansvarig myndigheter för önskade insatser föreslår rapporterande myndigheter allt från olika typer av familjestöd till direkta förslag till omhändertagande och placering på behandlingshem.

  • Ahlgren, Thorbjörn
    et al.
    Avdelningen för beteendevetenskap och socialt arbete, Hälsohögskolan, Jönköping University.
    Ahlgren, Thorbjörn
    Avdelningen för beteendevetenskap och socialt arbete, Hälsohögskolan, Jönköping University.
    Näslund, Johan
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Rosander, Michael
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Ungdomars attityder och beteende när det gäller att köpa och sälja sex: en studie i Jönköpings län våren 20082009Report (Other academic)
    Abstract [sv]

    Kunskapen om i vilken omfattning ungdomar har sålt eller köpt sex är begränsad. Delvis kan det bero på svårigheten med att bestämma vad som omfattas i begreppen sälja och köpa sex. Studier visar också att det i ungdomsrelationer förekommer att gåvor ges efter sexuella aktiviteter.

    I denna studie har totalt 16 personer (1,9 %) uppgett att de i olika omfattning utfört sexuella tjänster mot ersättning och att 79 personer (9,1 %) blivit erbjudna pengar eller annan ersättning för sexuella tjänster. Det är fler killar än tjejer som säljer sex. När det gäller att ha blivit erbjuden sex mot ersättning är det flest tjejer som svarat ja. Resultatet visar också att 131 personer (15,1 %) kan tänka sig att utföra sexuella tjänster mot ersättning. I svaren kan vi också utläsa att 348 personer (40,1%), mestadels killar, accepterar att andra utför sexuella tjänster mot ersättning.

    När det gäller i vilka kretsar de som säljer sex umgås är det tydligt att ungdomarna tittar mer på porr, att det är vanligare att de visar sig i sexuella situationer och att de har mindre tolerans mot homosexuella. Samlagsdebuten var ett år tidigare än hela undersökningsgruppen. Det är vanligare att man blivit utsatt för olika sexuella handlingar mot sin vilja, men man har också utsatt andra för sexuella handlingar mot deras vilja. Sammantaget kan vi se att ungdomarna i denna studie som sålt sex lever ett påtagligt mer sexualiserat liv än vad andra ungdomar i motsvarande ålder gör.

  • Adam, Lindberg
    Linköping University, Department of Culture and Communication.
    Adam, Lindberg
    Linköping University, Department of Culture and Communication.
    Den nya slöjden: Hur kan den svenska skolslöjden utvecklas mot att bli mer tekniskt inriktad?2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med studien är att belysa debatten/forskningen/rapporteringen kring den nordiska slöjdens utveckling mot ett ämne med en mer teknisk inriktning. Resultatet visar att det finns anledning att diskutera slöjdämnets utvecklingspotential. Det finns anledning att fortsätta undersöka om hur slöjden skulle kunna utvecklas mot teknisk inriktning. Det finns, som studien visar, fördelar för både slöjd- och teknikämnet att dra av en utveckling av slöjdämnet. Att samverka mellan ämnena kan ge positiva effekter inte bara för eleverna utan också för lärarna. Även om det inte blir en läroplansförändring i den snara framtiden, pekar detta arbete på att det finns anledning att slöjdlärare ute i skolorna börjar diskutera och arbeta närmare teknikämneslärarna. Det handlar också om att om slöjdämnet ska kunna fortsätta hävda sin plats i skolan bör slöjdämnet utvecklas. Med utveckling skulle slöjdämnet kunna gå från att vara en ifrågasatt del av skolan till att bli en självklarhet.

  • Näslund, Johan
    et al.
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Näslund, Johan
    Linköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Hau, Stephan
    Linköping University, Department of Behavioural Sciences and Learning, Clinical and Social Psychology. Linköping University, Faculty of Arts and Sciences.
    Inter-group relations between a group of football supporters, subgroups, and context in the initial phase of riots2011In: The individual and the group - Future challenges: Proceedings from the 7th GRASP conference, University of Gothenburg, May 2010 / [ed] Christian Jacobsson & Max Rapp Ricciardi, Göteborg: University of Gothenburg , 2011, 91-102 p.Conference paper (Other academic)
    Abstract [en]

    Within the frame of a project describing, analysing, and interpreting  inter-group actions in large groups, we analysed a ten-minute video-sequence during a so-called high-risk footballmatch when supporters acted violently.

    The local derby in Stockholm, Sweden, took place in august 2008. When these two teams meet usually high tension between the supporter groups develops and a large number of police officers are present, trying to prevent riots. The particular incident investigated took place right after a controversial penalty kick. The judgement of the referee was questioned and some fireworks were launched.

    Findings of a thorough video-analysis show extensive inter-group activities both between supporter subgroups and between supporter groups, as well as with the group of police officers and security personnel. At the same time evidence for self-policing could be found.

  • Näslund, Johan
    et al.
    Linköping University, Department of Behavioural Sciences. Linköping University, Faculty of Arts and Sciences.
    Näslund, JohanLinköping University, Department of Behavioural Sciences. Linköping University, Faculty of Arts and Sciences.Jern, StefanLund University.
    Interaction on the Edge: Proceedings from the 5th GRASP conference, Linköping University, May 20062007Conference proceedings (editor) (Other academic)
    Abstract [en]

    Since May 1998 Scandinavian group researchers and social psychologists have met bi-annually for what has to be called the GRASP conference. GRASP originally stood for ”Group as Paradox”. The first four conferences were held in Linköping, Lund, Stockholm and Skövde respectively.

    The fifth conference was organized at Linköping University May 11-12, 2006 under the auspices of the FOG FORUM group. Generous assistance was given by the Department of Behavioural Sciences and the Swedish Research Council (Vetenskapsrådet). This year’s theme was ”Interaction on the Edge” and a special emphasis was put on inter group processes. Sixty researchers from Sweden and Denmark took part and listened to thirty presentations. Twelve of these have been accepted for this proceeding volume.

  • Jern, Stefan
    et al.
    Lund Universtiy.
    Jern, StefanLund Universtiy.Näslund, JohanLinköping University, Department of Behavioural Sciences and Learning, Psychology. Linköping University, Faculty of Arts and Sciences.
    Dynamics Within and Outside the Lab: Proceedings from the 6th GRASP conference, Lund University, May 20082009Conference proceedings (editor) (Other academic)
    Abstract [en]

    Since May 1998 Scandinavian group researchers and social psychologists have met bi-annually for what has to be called the GRASP conference. GRASP originally stood for ”Group as Paradox”. The first five conferences were held in Linköping, Lund, Stockholm and Skövde and, again, Linköping.

    The sixth conference was organized at Lund University May 15-16, 2008 under the auspices of the network Organisational and Social Applications of  Psychology (POST) at the Department of Psychology, Lund University, in cooperation with the School of Social Work, Lund University, and Forum for field research in organisations and groups (FOG), Linköping University.

    Generous assistance was given by the the School of Social Work and the Swedish Council for Working Life and Social Research (FAS). This year’s theme was ”Dynamics within and outside the Lab” and a special emphasis was put on inter group processes. 60 researchers and students from Sweden and Norway took part and listened to twenty-seven presentations and two key-notes by Susan Wheelan, Ph.D. Eleven contributions have been chosen to represent the conference in this volume.

  • Toivainen, Sanne
    Linköping University, Department of Physics, Chemistry and Biology.
    Toivainen, Sanne
    Linköping University, Department of Physics, Chemistry and Biology.
    A study of haemoglobin: Egg laying, hatching, growth and summit metabolism.2016Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Haemoglobin and its functions in various organisms is well known; it increases the ability to obtain precious oxygen and it is crucial in aerobic performance. However, if high values of haemoglobin are always beneficial, why is there a large natural variation? This study investigated the effects of varying concentrations of haemoglobin on several stages in the lifespan of Red Junglefowl: egg production and hatching, chicken growth, haemoglobin and summit metabolism. Red Junglefowl were tested for fertility in both eggs laid and eggs hatched. The offspring were individually measured for whole blood haemoglobin concentration and tested for growth and summit metabolism. The results show that there is a difference in haemoglobin after two weeks of age and that growth differs at the same time. High Hb animals do not lay smaller nor fewer eggs than low line birds but their offspring are smaller at the same time as there is a difference in haemoglobin levels. There was also a difference in the summit metabolism between the lines, where the high line animals performed better. Importantly the increase in haemoglobin did effect the growth of the animals negatively, and this would imply that higher levels of haemoglobin is not detrimental to growth.

  • Public defence: 2016-10-27 09:00 Berzeliussalen, Linköping
    Rohini Rajan, Meenu
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Rohini Rajan, Meenu
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Unraveling Mechanisms of Insulin Resistance in Type 2 Diabetes in Human Aidpocytes: Role of extracelluar signal kinase 1/2 (ERK1/2) and farkhead box protein 01 (FOX01)2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Type 2 Diabetes is characterized by hyperglycemia primarily caused due to insulin resistance in insulin responsive tissues and insufficient production of insulin by the β-cells. Insulin resistance appears to develop first in the expanding adipose tissue during caloric surplus and affects other tissues like liver and muscle by ectopic fat accumulation. In spite of significant research in field of insulin signaling, very little has been known about the mechanisms that lead to insulin resistance and T2D.

    We aim for network-wide knowledge of insulin signaling in human adipocytes and to identify mechanisms that can induce insulin resistance in diabetic individuals. We have herein focused on the transcriptional control of insulin via ERK and FOXO1, and have used mathematical modelling to gain a systems-level understanding of insulin signaling network.

    Through the work in this thesis, we present for the first time a dynamic comprehensive model for insulin signaling for the adipocytes, for both metabolic and transcriptional control, and that can simulate data from both normal and diabetic individuals. We described insulin regulation of ERK phosphorylation and showed that both its insulin sensitivity and maxima  response to insulin was curtailed in adipocytes from diabetic individuals (Paper I). Our findings indicate that insulin regulated ERK pathway exerts control on transcription not only through phosphorylation of Elk-1 but also through phosphorylation of FOXO1 and exerts translational control via phosphorylation of ribosomal protein S6 (Paper I, II). Furthermore, we showed that insulin-induced FOXO1 phosphorylation or its insulin sensitivity was not impaired in diabetic individuals, although FOXO1 protein level was reduced by 45% in adipocytes from patients with type 2 diabetes. Comprehensive analysis of the detailed insulin signaling model showed that attenuation of the feedback from mTORC1 to IRS1-Ser307 explained dominant part of the insulin resistance seen in adipocytes from diabetic individuals (Paper II). More interestingly, inhibition of FOXO1 with a dominant negative construct of FOXO1, mimicked the diabetic state in the adipocytes, with the similarity extending to both insulin signaling as well as the reduced protein levels, as seen in the diabetic adipocytes. We also show that mTORC1 and FOXO1 maintain each other’s expression/activity in the human adipocytes (Paper II, III). Our findings thus demonstrate that the interplay between mTORC1 and FOXO1 maintains normal insulin signaling in the human adipocytes.

    List of papers
    1. A Single Mechanism Can Explain Network-wide Insulin Resistance in Adipocytes from Obese Patients with Type 2 Diabetes
    Open this publication in new window or tab >>A Single Mechanism Can Explain Network-wide Insulin Resistance in Adipocytes from Obese Patients with Type 2 Diabetes
    Show others...
    2014 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 289, no 48, 33215-33230 p.Article in journal (Refereed) Published
    Abstract [en]

    The response to insulin is impaired in type 2 diabetes. Much information is available about insulin signaling, but understanding of the cellular mechanisms causing impaired signaling and insulin resistance is hampered by fragmented data, mainly obtained from different cell lines and animals. We have collected quantitative and systems-wide dynamic data on insulin signaling in primary adipocytes and compared cells isolated from healthy and diabetic individuals. Mathematical modeling and experimental verification identified mechanisms of insulin control of the MAPKs ERK1/2. We found that in human adipocytes, insulin stimulates phosphorylation of the ribosomal protein S6 and hence protein synthesis about equally via ERK1/2 and mTORC1. Using mathematical modeling, we examined the signaling network as a whole and show that a single mechanism can explain the insulin resistance of type 2 diabetes throughout the network, involving signaling both through IRS1, PKB, and mTOR and via ERK1/2 to the nuclear transcription factor Elk1. The most important part of the insulin resistance mechanism is an attenuated feedback from the protein kinase mTORC1 to IRS1, which spreads signal attenuation to all parts of the insulin signaling network. Experimental inhibition of mTORC1 using rapamycin in adipocytes from non-diabetic individuals induced and thus confirmed the predicted network-wide insulin resistance.

    Place, publisher, year, edition, pages
    American Society for Biochemistry and Molecular Biology, 2014
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-113198 (URN)10.1074/jbc.M114.608927 (DOI)000345636600015 ()25320095 (PubMedID)
    Note

    Funding Agencies|Swedish Diabetes Fund; University of Linkoping; Swedish Research Council

    Available from: 2015-01-13 Created: 2015-01-12 Last updated: 2016-09-19
    2. Systems-wide Experimental and Modeling Analysis of Insulin Signaling through Forkhead Box Protein O1 (FOXO1) in Human Adipocytes, Normally and in Type 2 Diabetes
    Open this publication in new window or tab >>Systems-wide Experimental and Modeling Analysis of Insulin Signaling through Forkhead Box Protein O1 (FOXO1) in Human Adipocytes, Normally and in Type 2 Diabetes
    Show others...
    2016 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 291, no 30, 15806-15819 p.Article in journal (Refereed) Published
    Abstract [en]

    Insulin resistance is a major aspect of type 2 diabetes (T2D), which results from impaired insulin signaling in target cells. Signaling to regulate forkhead box protein O1 (FOXO1) may be the most important mechanism for insulin to control transcription. Despite this, little is known about how insulin regulates FOXO1 and how FOXO1 may contribute to insulin resistance in adipocytes, which are the most critical cell type in the development of insulin resistance. We report a detailed mechanistic analysis of insulin control of FOXO1 in human adipocytes obtained from non-diabetic subjects and from patients with T2D. We show that FOXO1 is mainly phosphorylated through mTORC2-mediated phosphorylation of protein kinase B at Ser(473) and that this mechanism is unperturbed in T2D. We also demonstrate a cross-talk from the MAPK branch of insulin signaling to stimulate phosphorylation of FOXO1. The cellular abundance and consequently activity of FOXO1 are halved in T2D. Interestingly, inhibition of mTORC1 with rapamycin reduces the abundance of FOXO1 to the levels in T2D. This suggests that the reduction of the concentration of FOXO1 is a consequence of attenuation of mTORC1, which defines much of the diabetic state in human adipocytes. We integrate insulin control of FOXO1 in a network-wide mathematical model of insulin signaling dynamics based on compatible data from human adipocytes. The diabetic state is network-wide explained by attenuation of an mTORC1-to-insulin receptor substrate-1 (IRS1) feedback and reduced abundances of insulin receptor, GLUT4, AS160, ribosomal protein S6, and FOXO1. The model demonstrates that attenuation of the mTORC1-to-IRS1 feedback is a major mechanism of insulin resistance in the diabetic state.

    Place, publisher, year, edition, pages
    Rockville, Maryland: American Society for Biochemistry and Molecular Biology, 2016
    National Category
    Endocrinology and Diabetes
    Identifiers
    urn:nbn:se:liu:diva-130998 (URN)10.1074/jbc.M116.715763 (DOI)000380584200033 ()27226562 (PubMedID)
    Note

    Funding agencies|Swedish Diabetes Fund, University of Linköping; Swedish Research Council; AstraZeneca

    Available from: 2016-09-02 Created: 2016-09-02 Last updated: 2016-09-19Bibliographically approved
  • Public defence: 2016-10-21 13:15 Visionen, Hus B, Linköping
    Forsblad (Kristiansson), Mattias
    Linköping University, Department of Computer and Information Science, Human-Centered systems. Linköping University, Faculty of Arts and Sciences.
    Forsblad (Kristiansson), Mattias
    Linköping University, Department of Computer and Information Science, Human-Centered systems. Linköping University, Faculty of Arts and Sciences.
    Distributed cognition in home environments: The prospective memory and cognitive practices of older adults2016Doctoral thesis, monograph (Other academic)
    Abstract [en]

    In this thesis I explore how older people make use of, and interact with, their physical environment in home and near-by settings to manage cognitive situations, specifically prospective memory situations. Older adults have in past research been shown to perform better on prospective memory in real-life settings than what findings in laboratory-like settings predict. An explanation for this paradox is that older adults has a more developed skill of using the environment for prospective memory than younger adults. However, research investigating this explanation has primarily been based on self-reports.

    I contribute to the understanding of this skill by doing two related things. First I introduce distributed cognition, a theoretical perspective that primarily has been used within professional and socio-technical environments, to the research field of prospective memory in everyday life. Second I present a cognitive ethnography conducted during two years across eight home, and near-by, environments and old-age retired persons, for which I have used theoretical concepts from distributed cognition to analyze observations.

    The analysis shows rich variations in how participants use common cultural cognitive tools, invent their own cognitive tools, deliberately and incidentally shape more or less functional spaces, make use of other physical features, orient themselves toward and make sense of cognitive resources. I complement both prospective memory and distributed cognition research by describing both the intelligent shaping and use of space. Furthermore, by taking a distributed cognitive perspective I show that prospective memory processes in home environments involve properties, and the management, of a multipurpose environment.

    Altogether this supports the understanding of distributed cognition as a perspective on all cognition. Distributed cognition is not a reflection of particular work practices, instead it is a formulation of the general features of human cognition. Prospective memory in everyday life can be understood as an ability persons have. However, in this thesis I show that prospective memory can also be understood as a process that takes place between persons, arrangements of space, and tools.

  • Dahl, Kristoffer
    Linköping University, Department of Physics, Chemistry and Biology.
    Dahl, Kristoffer
    Linköping University, Department of Physics, Chemistry and Biology.
    Management effects on butterfly and bumblebee abundance in Swedish semi-natural grasslands2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The amount of semi-natural grasslands has decreased in the agricultural landscape and because of this many grassland species are declining. Semi-natural grasslands are dependent on management, but different studies suggest that different management methods are most favorable to species richness and abundance. The aim of this study was to compare the effects of mowing and grazing on butterfly and bumblebee abundance in Swedish semi-natural grasslands. We used data collected through the Swedish environmental monitoring program NILS. We identified 31 comparable meadows and chose 1-10 pastures in the area surrounding each meadow. For six different species groups we calculated the number of individuals found per 100 m. By standardizing the values of the difference between the means for meadows and pastures we were able to compare the effects of the two methods on abundance in each species group. No species group showed a preference for pastures. A significant preference for meadows was found for two butterfly species groups. The four other groups showed a trend to prefer meadows before pastures. According to our study the recommended management method should be mowing, considering protection of butterflies and bumblebees.

  • Maria Marreiros, Filipe Miguel
    Universidade do Algarve, Vision Laboratory, Portugal.
    Maria Marreiros, Filipe Miguel
    Universidade do Algarve, Vision Laboratory, Portugal.
    Real-Time Direct Volume Rendering2002Independent thesis Basic level (university diploma), 20 credits / 30 HE creditsStudent thesis
    Abstract [pt]

    The goal of this project is to create a software application that permits the visualizationof 3D sampled scalar data, also known as Volume Data, using a technique calledDirect Volume Rendering (DVR). This technique allows the creation of an image thatrepresents the entire data set, including the visualization of the interior of the volume,i.e., not just the surface. The drawback of this technique is the tremendous storageand processing requirement, since it needs the entire volume information in order togenerate the image. In order to generate this image one of the DVR algorithms waschosen: the Ray-Casting algorithm.

    The software allows the user to interact with the volume, changing the colour andthe opacity, the illumination and rotation, among other things. Volume rotations canbe done in real-time, the other changes are incorporated in a pre-processing step.To be able to achieve real-time volume rotations, the Ray-Casting algorithm wasoptimized and parallelized. To speed up even more the frame rate, a different versionof the parallel algorithm was developed, called the interactive mode, which sacrificessome image quality.

    he Message Passing Interface (MPI) was used as a tool for the parallelization.The software was developed and tested on the Beowulf cluster “Calhau”. This clusterallows a real-time rotation of large volumes, up to 256^3 voxels.

  • Maria Marreiros, Filipe Miguel
    Universidade do Minho, Escola de Engenharia, Departamento de Informática.
    Maria Marreiros, Filipe Miguel
    Universidade do Minho, Escola de Engenharia, Departamento de Informática.
    Análise e interpretação de imagem médica com o apoio de agentes de software2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The artefacts evolution used in the medical imaging practice, going from 3-tesla Magnetic Resonance (MR) units and 64-slice Computer Tomography (CT) systems to the latest generation of hybrid Positron Emission Tomography (PET)/CT technologies is producing a huge volume of images that threatens to overload the capacity of the interpreting radiologists. The current workflow reading practices are becoming inadequate for reviewing the 300 to 500 images of a routine CT of the chest, abdomen, or pelvis, and are less so far the 1500 to 2000 images of a CT angiography or functional MR study. However the image visualization computer programs continue to present the same schema to analyse the images. Basically, imitating themanual process of film visualization as can be found in most commercial medical viewers. Onthe other hand agent based computing has been hailed as significant break-through in software development and analysis. Multiagents systems are revelling success in a wide variety ofresearch and application fields.

    This work concerns the development of a multiagent system that enables a multidisplay medical image diagnostic system. The multiagent system architecture is a scalable one, either in termsof display area or in terms of knowledge agents for computer aided diagnostic and intelligent hanging protocol tasks. In this work it is presented an approach to overcome the medical imaging reading problem, by implementing alternative navigation strategies that leads to an“intelligent” hanging of images, which, in turn, determines an exponential increase of thediagnostic area. The developed multiagent architecture and its agents are described in detail, and implementation issues of a prototype created for assessment purposes are also object of attention.

  • Odhiambo, Moses
    et al.
    Linköping University, Department of Thematic Studies, Tema Environmental Change.
    Odhiambo, Moses
    Linköping University, Department of Thematic Studies, Tema Environmental Change.
    Routh, Joyanto
    Linköping University, Department of Thematic Studies, Tema Environmental Change.
    Distribution of black carbon and its impact on Eutrophication in Lake Victoria2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Lake Victoria (LV), is the largest tropical fresh water lake. It is however facing a myriad of challenges like eutrophication, introducing species, mass extinction and climate change. Eutrophication has mostly been seen as a result of non-point pollution from upstream agricultural areas. However, studies have found that atmospheric deposition could perhaps be the greatest cause of nutrient loading in the lake. Our study looked at black carbon as one of the factors favoring eutrophication in LV. Black carbon is a product of incomplete combustion of biomass or fossil fuel. Biomass burning is prevalent in many areas of Africa and our results have shown a great spatial and temporal variability in its concentration in sediments. The sedimentation rates calculated after analyzing 210Pb activity were 0.87, 0.53 and 0.35 g cm-2 yr-1 while the average black carbon concentrations were 4.6, 2.1 and 6.9 mg g-1 for Siaya, Kisumu and Busia, respectively. These results provided valuable information when compared to past historical events in the Lake region especially eutrophication. The study also found that soot BC has been increasing in the past 100 years suggesting the input from fossil fuels. This study elucidates the complexity of drivers of eutrophication in Lake Victoria. Nitrogen and Phosphorous from the upstream agricultural sites has long been seen as the main cause of eutrophication. Through this study we find that soot deposition in the lake coincides with the period of increased primary productivity. The Total Organic Carbon and Total Nitrogen were also analyzed and have shown increased remarkable increase with time. All these geochemical variables are a testament to the increased role of human activities on the lake’s productivity. While other studies on soot in marine environments have associated bacterial growth to nutrients attached to soot black carbon. We correlate the concentration of soot in Lake Victoria basin to blooming of cyanobacteria.

  • Diverde, Hannah
    Linköping University, Department of Thematic Studies, Tema Environmental Change.
    Diverde, Hannah
    Linköping University, Department of Thematic Studies, Tema Environmental Change.
    The European Green Capital Award as a tool for the environmental work in Umeå2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Urban areas are facing huge environmental challenges due to an increase in the population from 50% to 70% until 2050. The European Commission promotes the European Green Capital Award to give European cities motivation to facilitate a change towards urban sustainable development in medium-sized cities, where the city Umeå in north Sweden is applying for the third time. The aim of this study is to see whether the award is a useful tool for the environmental work in Umeå and if there are controversies among the stakeholders of the city. Interviews have been conducted where interviewees from several areas, both pro and against the award, have been interviewed. It is shown that the award has several impacts where most of them are beneficial for the environmental work in the city, such as structuring the environmental work. The main challenge with the award is a communication failure between the project group and other stakeholders of the city. The conclusion is that the award in itself seem to be good for the environmental work in Umeå but that the communication between the project group and the citizens needs to be improved.

  • Lemón, Linn
    Linköping University, Department of Biomedical Engineering.
    Lemón, Linn
    Linköping University, Department of Biomedical Engineering.
    Topology optimization process for new designs of reconstruction plates used for bridging large mandibular defects2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Loss of bone in the mandible as a result from for example resection of bone tumors or trauma, can in more complex cases be reconstructed using a reconstruction plate to provide stability between the remaining mandible stumps. Different studies on reconstruction plates present a fracture rate of 2.8-9.8 %. The rate of plate fracture and plate loosening increases the need to improve the design of the reconstruction plate. A useful tool to find new designs for structures is topology optimization. Topology optimization is a mathematical based method where it is possible to define an optimization problem for a specific load case. Based on the defined problem, the solver calculates the most appropriate design to reach the final goal. The aim of this work is to investigate, describe, and discuss how new designs for reconstruction plates used for bridging large mandibular defects can be achieved by using topology optimization as a tool.

     

    Two software programs handling topology optimization from Altair Engineering were used: SimLab 14.0 and HyperMesh 14.0. Both of them uses the solver OptiStruct to solve the defined topology optimization problem. The topology optimization problem was defined to minimize the compliance of the structure with an upper limit of the allowed volume fraction used for the new design. Three different clenching tasks were examined: right unilateral clench, clenching in the intercuspal position, and incisal clench. All three load cases resulted in different designs, the designs were also affected by the initial amount of screws used, and by the defined value on the allowed thickness of the created parts in the new design. The results gave an initial understanding of topology optimization, and indicated the possibilities a design process with topology optimization has to achieve new designs for reconstruction plates used for large mandibular fractures. 

  • Svahnström, Kristina
    Linköping University, Department of Computer and Information Science.
    Svahnström, Kristina
    Linköping University, Department of Computer and Information Science.
    Sensorer och annan teknik i hemmet som stöd för att multisjuka äldre ska kunna bo kvar hemma: Vem är den typiska potentiella användaren?2016Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis
    Abstract [sv]

    I takt med att befolkningen blir allt äldre ökar vårdbehovet, andelen äldre som behöver stöd för att kunna bo kvar hemma och således också kostnaderna för vård och omsorg. En lösning på problemet skulle kunna vara att använda olika typer av sensorer och att patienten själv kan mäta vissa fysiologiska värden, rapportera in dem och kommunicera med sjukvården hemifrån. Semistrukturerade intervjuer har utförts på patienter som fortfarande bor kvar hemma och har kronisk obstruktiv lungsjukdom (KOL) eller annan lungsjukdom för att kartlägga vilka de potentiella användarna av systemet är och vilka förutsättningar, önskemål och förväntningar de har på ett sådant system. Studien har visat att den typiska potentiella användaren, baserat på intervjudeltagarnas svar, är positivt inställd till att ha sensorer och annan teknik i sitt hem som stöd för att kunna bo kvar hemma och att det finns ett flertal begränsningar och önskemål som utvecklarna av ett sådant system måste ta hänsyn till, vilka presenteras i en persona och scenarier.

  • Johnsson, Teodor
    Linköping University, Department of Electrical Engineering, Automatic Control.
    Johnsson, Teodor
    Linköping University, Department of Electrical Engineering, Automatic Control.
    Autonomous Following and Filming of a Test Vehicle2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Quadcopters have been used as filming platforms for years and are mainly man-ually controlled, with its inherited difficulties. The objective of this thesis projectwas to eliminate the human factor by developing and constructing a prototypefor an autonomous filming platform at BorgWarner AB. Different methods forfollowing and filming the test vehicles were investigated with the use of differentsensors, such as Global Navigation Satellite Systems (GNSS) and Inertial Navi-gation System (INS). These were evaluated by simulations in Simulink where itwas shown that an improved reference following could be achieved by the use ofa complementary filter. Further development was focused on writing a controlsystem for the prototype in which the following-algorithms and prototype couldbe evaluated. Final testing resulted in the conclusion that the desired objectivewas feasible with the current platform. There were however some limitations inthe desired change in direction of the quadcopter, first discovered during simu-lations and proven during experimental testing.

  • Krantz, Kristin (Editor)
    Linköping University, University Library.
    Krantz, Kristin (Editor)
    Linköping University, University Library.
    Verksamhetsberättelse LiUB 20152015Report (Other academic)
  • Skoglund, Ingegerd (Editor, Photographer)
    Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
    Skoglund, Ingegerd (Editor, Photographer)
    Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
    Verksamhetsberättelse 2015: Matematiska institutionen2015Report (Other academic)
  • Lindberg, Pontus
    Linköping University, Department of Electrical Engineering, Computer Vision.
    Lindberg, Pontus
    Linköping University, Department of Electrical Engineering, Computer Vision.
    Automatisk volymmätning av virkestravar på lastbil2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Automatic measurment of volume for on-truck timber stacks is a measurment system that measures the woodvolume. The whole system consist of six sensorsystems. Each sensor is at first individually calibrated and then calibrated together to give a merged worldcoordinate system. Each sensor produces a depth image and are flectance image where the values in the depth image represents the distance from the sensor. The consistuent has developed a algoritm which from the measured data estimates the woodvolume to a certain accuracy that fullfills the requirements stated from the forest industry for automatic measurent of timber stacks on trucks. I this thesis we will analyze if better measurement results can be achieved with other methods or combinations of them. At disposal we have about 125 datasets of timber stacks where the key exists. The key consists of random samples that have been manually measured log by log. A active choice to not take part of the consistuent´s algoritm was made to not be coloured of how they acheived their results. Mainly the front- and backside images of at imberstack is used to find the logs. Subsequentlythefound logs are interpolated into the middle of the timber stack or are paired together. Sometimes there exists some problems with the images. Frequently at least on the sides are occluded by the cabin, crane or another timber stack. Then estimation is required from the visible data to make a qualified guess of the occluded areas. In the beginning of this thesis two methods where analysed, the MSER features method and the pointplane method. The main purpose of those two methods was to analyse if a good results could be acheived by just measuring the data and using it as a initial volume estimate. Though it was discovered that valuable details was missed to be able to more accuratly determine the woodvolume. Examples of such details is the distribution of diameter on the found logs. Also these methods tended to heavily over- or underestimate when the timber stack had a certain amount of brushwood and or badly limbed logs. After that a geometric method was constructed, and it was this method that most time and analysis was spent on. In the figures below a table and a graph where the under bark results of all three methods and the interval limits of forest industry requirements.

  • Toverland, Johan
    Linköping University, Department of Electrical Engineering, Automatic Control.
    Toverland, Johan
    Linköping University, Department of Electrical Engineering, Automatic Control.
    Thermal Modelling of Voicecoils in Microspeakers2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Microspeakers can overheat and break if not monitored and regulated. This monitoringis usually done by adding a pilot tone that introduces energy to the signal.A problem with this approach is the slow update rate of the temperature estimate.This in combination with a fast temperature rise could result in an audible regulationof the input. By simulating the voice coil temperature these problems couldbe mitigated. In this thesis, two existing grey box models and one novel black boxmodel are estimated for different speakers and evaluated using different signals.The results are promising and indicate that all models can estimate the voice coiltemperature with a mean error below one degree. The tests show that a correctinitialization of the model is crucial. Therefore the suggestion to Cirrus Logic,who hosted this thesis project, is to combine a feedforward model with eithertemperature sensor data from the mobile device or a pilot tone.

  • Public defence: 2016-10-18 10:15 TP2, Täppan, Norrköping
    He, Qing
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    He, Qing
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    A Comprehensive Analysis of Optimal Link Scheduling for Emptying a Wireless Network2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Wireless communications have become an important part of modern life. The ubiquitous wireless networks and connectivities generate exponentially increasing data traffic. In view of this, wireless network optimization, which aims at utilizing the limited resource, especially spectrum and energy, as efficiently as possible from a network perspective, is essential for performance improvement and sustainable development of wireless communications.

    In the dissertation, we focus on a fundamental problem of wireless network optimization, link scheduling, as well as its subproblem, link activation. The problem type arises because of the nature of wireless media and hence it is of relevance to a wide range of networks with multiple access. We freshen these classic problems up by novel extensions incorporating new technologies of interference management or with new performance metrics. We also revisit the problems in their classic setup to gain new theoretical results and insights for problem-solving. Throughout the study, we consider the problems with a general setup, such that the insights presented in this dissertation are not constrained to a specific technology or network type. Since link activation and scheduling are key elements of access coordination in wireless communications, the study opens up new approaches that significantly improve network performance, and eventually benefit practical applications.

    The dissertation consists of five research papers. The first paper addresses maximum link activation with cooperative transmission and interference cancellation. Papers II and III investigate the minimum-time link scheduling problem in general and a particular class of networks, respectively. In Paper IV, we consider the scheduling problem of emptying a network in its broad form and provide a general optimality condition. In Paper V, we study the scheduling problem with respect to age of information.

    List of papers
    1. Maximum Link Activation with Cooperative Transmission and Interference Cancellation in Wireless Networks
    Open this publication in new window or tab >>Maximum Link Activation with Cooperative Transmission and Interference Cancellation in Wireless Networks
    2016 (English)In: IEEE Transactions on Mobile Computing, ISSN 1536-1233, E-ISSN 1558-0660, 1-1 p.Article in journal (Other academic) Published
    Abstract [en]

    We address the maximum link activation problem in wireless networks with new features, namely when the transmitters can perform cooperative transmission, and the receivers are able to perform successive interference cancellation. In this new problem setting, which transmitters should transmit and to whom, as well as the optimal cancellation patterns at the receivers, are strongly intertwined. We present contributions along three lines. First, we provide a thorough tractability analysis, proving the NP-hardness as well as identifying tractable cases. Second, for benchmarking purposes, we deploy integer linear programming for achieving global optimum using off-theshelf optimization methods. Third, to overcome the scalability issue of integer programming, we design a sub-optimal but efficient optimization algorithm for the problem in its general form, by embedding maximum-weighted bipartite matching into local search. Numerical results are presented for performance evaluation, to validate the benefit of cooperative transmission and interference cancellation for maximum link activation and to demonstrate the effectiveness of the proposed algorithm.

    Place, publisher, year, edition, pages
    IEEE, 2016
    National Category
    Communication Systems Telecommunications
    Identifiers
    urn:nbn:se:liu:diva-112447 (URN)10.1109/TMC.2016.2546906 (DOI)
    Conference
    2014 IEEE 25th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), September 2-5, Washington DC, DC, USA
    Available from: 2014-11-27 Created: 2014-11-27 Last updated: 2016-09-19Bibliographically approved
    2. Minimum-Time Link Scheduling for Emptying Wireless Systems: Solution Characterization and Algorithmic Framework
    Open this publication in new window or tab >>Minimum-Time Link Scheduling for Emptying Wireless Systems: Solution Characterization and Algorithmic Framework
    2014 (English)In: IEEE Transactions on Information Theory, ISSN 0018-9448, Vol. 60, no 2, 1083-1100 p.Article in journal (Refereed) Published
    Abstract [en]

    We consider a set of transmitter-receiver pairs, or links, that share a wireless medium and address the problem of emptying backlogged queues with given initial size at the transmitters in minimum time. The problem amounts to determining activation subsets of links, and their time durations, to form a minimum-time schedule. Scheduling in wireless networks has been studied under various formulations before. In this paper, we present fundamental insights and solution characterizations that include: 1) showing that the complexity of the problem remains high for any continuous and increasing rate function; 2) formulating and proving sufficient and necessary optimality conditions of two baseline scheduling strategies that correspond to emptying the queues using one-at-a-time or all-at-once strategies; and 3) presenting and proving the tractability of the special case in which the transmission rates are functions only of the cardinality of the link activation sets. These results are independent of physical-layer system specifications and are valid for any form of rate function. We then develop an algorithmic framework for the solution to this problem. The framework encompasses exact as well as sub-optimal, but fast, scheduling algorithms, all under a unified principle design. Through computational experiments, we finally investigate the performance of several specific algorithms from this framework.

    Place, publisher, year, edition, pages
    Institute of Electrical and Electronics Engineers (IEEE), 2014
    Keyword
    Algorithm; optimality; scheduling; wireless networks
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-104836 (URN)10.1109/TIT.2013.2292065 (DOI)000330286100022 ()
    Available from: 2014-02-28 Created: 2014-02-28 Last updated: 2016-09-15
    3. Polynomial Complexity Minimum-Time Scheduling in a Class of Wireless Networks
    Open this publication in new window or tab >>Polynomial Complexity Minimum-Time Scheduling in a Class of Wireless Networks
    2015 (English)In: IEEE Transactions on Control of Network Systems, ISSN 2325-5870 (Print), 2325-5870 (online), Vol. 3, no 3, 322-331 p.Article in journal (Other academic) Epub ahead of print
    Abstract [en]

    We consider a wireless network with a set of transmitter-receiver pairs, or links, that share a common channel, and address the problem of emptying finite traffic volume from the transmitters in minimum time. This, so called, minimum-time scheduling problem has been proved to be NP-hard in general. In this paper, we study a class of minimum-time scheduling problems in which the link rates have a particular structure. We show that global optimality can be reached in polynomial time and derive optimality conditions. Then we consider a more general case in which we apply the same approach and obtain an approximation as well as lower and upper bounds to the optimal solution. Simulation results confirm and validate our approach.

    Place, publisher, year, edition, pages
    Institute of Electrical and Electronics Engineers (IEEE), 2015
    Keyword
    algorithm, interference, optimality, scheduling, wireless networks
    National Category
    Communication Systems Telecommunications
    Identifiers
    urn:nbn:se:liu:diva-112446 (URN)10.1109/TCNS.2015.2512678 (DOI)
    Note

    At the time for thesis presentation publication was in status: Manuscript

    Available from: 2014-11-27 Created: 2014-11-27 Last updated: 2016-09-16Bibliographically approved
    4. A general optimality condition of link scheduling for emptying a wireless network
    Open this publication in new window or tab >>A general optimality condition of link scheduling for emptying a wireless network
    2016 (English)Conference paper (Refereed)
    Abstract [en]

    We consider link scheduling in wireless networks for emptying the queues of the source nodes, and provide a unified mathematical formulation that accommodates all meaningful settings of link transmission rates and network configurations. We prove that, any scheduling problem is equivalent to solving a convex problem defined over the convex hull of the rate region. Based on the fundamental insight, a general optimality condition is derived, that yields a unified treatment of optimal scheduling. Furthermore, we demonstrate the implications and usefulness of the result. Specifically, by applying the theoretical insight to optimality characterization and complexity analysis of scheduling problems, we can both unify and extend previously obtained results.

    Place, publisher, year, edition, pages
    IEEE, 2016
    Series
    , IEEE International Symposium on Information Theory. Proceedings, ISSN 2157-8095 (Print), 2157-8117 (online) ; 2016
    Keyword
    convex programming;radio links;radio networks;telecommunication scheduling;convex hull;convex problem;general optimality condition;link scheduling;link transmission rates;network configurations;optimal scheduling;source nodes;wireless network;Complexity theory;Information theory;Interference;Optimal scheduling;Processor scheduling;Scheduling;Wireless networks;complexity;optimality;scheduling;wireless networks
    National Category
    Computer Engineering Information Systems Software Engineering
    Identifiers
    urn:nbn:se:liu:diva-131357 (URN)10.1109/ISIT.2016.7541538 (DOI)
    Conference
    IEEE International Symposium on Information Theory (ISIT), 2016, Universitat Pompeu Fabra, Barcelona, Spain, July l0-l5, 2016
    Available from: 2016-09-15 Created: 2016-09-15 Last updated: 2016-09-15Bibliographically approved
  • Assis Lana e Cruz, Igor
    Linköping University, Department of Management and Engineering, Energy Systems.
    Assis Lana e Cruz, Igor
    Linköping University, Department of Management and Engineering, Energy Systems.
    Energy and material balances of wastewater treatment, including biogas production, at a recycled board mill2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Challenges surrounding energy have gained increased attention, which is not least reflected in the 2030 Agenda for Sustainable Development and the Sustainable Development Goals (SDGs). Energy issues have also become a pressing matter for most countries in the last decades. The reasons for this are not only related to the effects of the emission of greenhouse gases (GHG) from fossil fuels and their impact in climate change, but also span through other issues such as security of energy supply with geopolitical considerations and competitiveness of industry. To address these issues, a collection of public policies ranging from the international to local levels have been implemented.

    Sweden has historically had lower energy prices than its European counterparts, which has resulted in its industry having a relatively higher share of electricity in the total energy use by industry. The share of electricity accounts for 35% of total energy use in Swedish industry. This has led to efficiency measures being overlooked by industry, and the pulp and paper industry is by far the biggest energy user, with a share of 51% of the total energy use by industry. The variation of energy prices, and particularly electricity prices have obvious implications on the competitiveness of this sector.

    Production of biogas in pulp and paper mills has been gaining attention, and is now the target of an increasing number of scientific studies. The interest for this industry is not only related to security of energy supply and the environmental performance of the biogas itself, but there are also considerations regarding the biogas plant as an alternative to treat the large flows of wastewaters and other waste stream in this sector. There is an estimated biogas production potential of 1 TWh within this industry in Sweden, which accounts for 60% of the current biogas production in the country.

    Pulp and paper mills commonly rely on aerated biological treatment to deal with waste streams with high organic content This biological process has a high energy demand, and the integration of an anaerobic treatment, along with the use of the biogas for heat and electricity can yield a net positive energy recovery for the combined plant.

    This project analyses the current energy and material performance of an anaerobic biological treatment combined with an aerobic biological treatment in a recycled board mill. The anaerobic treatment is performed upstream of the aerobic one and removes most of the chemical oxygen demand of the wastewater.

    Energy and material balances for the plant are presented, and a comparison of the wastewater treatment plant running before and after the start-up of the biogas plant is made. The plant operation with the anaerobic digestion has shown an increased energy use of 9.4% coupled to an increased flow of wastewater of 7.7%. The average biogas production is 72 Nm³/h, which accounts for 440 kWh and is currently being flared. The introduction of AD has largely decrease the organic load in the aerobic treatment, by nearly 50%. This project ends with an optimisation model implemented with the optimisation tool reMIND to investigate potential optimisation strategies for the operation of the combined plant. The model has shown to be adequate to describe electricity use with mean error below 10%. For the biogas production, the mean error was of 16%.