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• Linköping University, Department of Biomedical Engineering.
Real-time ECG for objective stress level measurement2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
• Linköping University, Department of Biomedical Engineering.
DEVELOPING COMPUTATIONAL METHODS TOPREDICT THE FATE OF INHALED PARTICLES IN THELUNG2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
• Linköping University, Department of Biomedical Engineering, Division of Biomedical Engineering.
Identifying patterns in physiological parameters of expert and novice marksmen in simulation environment related to performance outcomes2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

The goal of this thesis is to investigate if it is possible to use measurements of physiological parameters to accelerate learning of target shooting for novice marksmen in Saab’s Ground combat indoor trainer (GC-IDT). This was done through a literature study that identified brain activity, eye movements, heart activity, muscle activity and breathing as related to shooting technique. The sensors types Electroencephalography (EEG), Electroocculography (EOG), Electrocardiogram (ECG), Electromyography (EMG) and impedance pneumography (IP) were found to be suitable for measuring the respective parameters in the GC-IDT.

The literature study also showed that previous studies had found differences in the physiological parameters in the seconds leading up to the shot when comparing experts and novices. The studies further showed that it was possible to accelerate learning by giving feedback to the novices about their physiological parameters allowing them to mimic the behavior of the experts.

An experiment was performed in the GC-IDT by measuring EOG, ECG, EMG and IP on expert and novice marksmen to investigate if similar results as seen in previous studies were to be found. The experiment showed correlation between eye movements and shooting score, which was in line with what previous studies had shown. The respiration measurement did not show any correlation to the shooting scores in this experiment, it was however possible to see a slight difference between expert and novices. The other measurements did not show any correlation to the shooting score in this experiment. In the future, further experiments needs to be made as not all parameters could be explored in depth in this experiment. Possible improvements to such experiments are i.e. increasing the number of participants and/or the number of shots as well as marking shots automatically in the data and increasing the time between shots.

• Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
A Noncommutative Catenoid2017Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis

Noncommutative geometry generalizes many geometric results from such ﬁelds as diﬀerential geometry and algebraic geometry to a context where commutativity cannot be assumed. Unfortunately there are few concrete non-trivial examples of noncommutative objects. The aim of this thesis is to construct a noncommutative surface $\mathcal{C}_\hbar$ which will be a generalization of the well known surface called the catenoid. This surface will be constructed using the Diamond lemma, derivations will be constructed over $\mathcal{C}_\hbar$ and a general localization will be provided using the Ore condition.

Projektstyrning: En jämförande fallstudie om nutida och historiska faktorers påverkan2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Background: The fact that companies carry out projects have become more common inrecent decades. Projects are often described based on the time limit that surrounds theproject where the project is unique while it is part of the company's history and the futureability to conduct project work. It has proved difficult to control projects based on the modelscreated for traditional organizations and there is a need for increased knowledge on howcontrol can be understood in relation to projects.

Aim: The aim of this study is to contribute to increased understanding of the similarities anddifferences in what leads to change in different projects and how the management of projectscan be understood from the company's control system.

Methodology: This study is based on two projects and the companies the projects are partof. The study has a qualitative approach in which semistructured interviews were used fordata collection.

Conclusions: Management's change in projects can not only be explained by studyingcurrent and situational variables. Current and situational variables are important tounderstand why management changes, but by studying the history of companies andprojects, the change of management can be better explained. The impact of the projectmanager and project members on the change of control is important in explaining whymanagement changes based on different starting points in different projects.

Den osynliga styrningen: En studie i självorganiseringens styrningsmekanismer2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Background: Our study investigates the phenomenon of self-organization since many companies choose to work in smaller teams and project groups to respond proactively to change. Problems that may arise with a greater delegation of responsibility in organizations is insufficient goal congruence throughout the different organizational levels. Management control is the solution to problems with goal congruence but its meaning is often translated into the monitoring and supervision of employees. This creates negative associations to the influence that management control has over work performances in self-organizing teams. Organizations are therefore forced to balance their exercise of control between a tougher and more free form of governance to reach goal congruence in all organizational levels. Self- organization thus places high demands on management when control is to be transparent to employees and at the same time congruent with the self-organization that is conducted throughout the organization.

Purpose: To create an in-depth understanding of the prerequisites and control mechanisms of self-organization. Completion: The study adopts a qualitative method in which data was collected from SMHI's IT department. During four weeks, material was collected from four interviews with representatives from three different organizational levels.

Conclusion: The study results in the coexistence of though and free control through transparent control mechanisms to ensure goal congruence in self-organized work. The results proves how the client's involvement in teamwork and the group's priorities are driven by cultural and self-managing mechanisms. Furthermore, the cybernetic process with interactive features is described as a tough control that generates increased autonomy in self-organizing teams. To achieve well-functioning self-organizing teams the prerequisites instigate knowledge sharing, communication and flexibility in the work process. The control mechanisms and the prerequisites of the team contribute to the perceived autonomy amongst the team members to influence their work, which is the most important factor for the control to appear invisible. The parallel work of prerequisites and control mechanisms creates effective and well-functioning teams working towards congruence with the organization's goals. In organizations that require flexibility and efficiency through team-based work, these dimensions are tools used by management to control teams with transparency

Samhälleligt ansvarstagande: En komparativ fallstudie av det samhälleliga ansvarstagandets mening och betydelse för medarbetaren2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Background In our society, the question of social responsibility is of importance for most companies and it has long been a subject for scholars. Studies of employees in social responsible companies indicate a positive correlation between CSR activities and motivation. However, only a few have focused on the employee and none of the previous studies have used sensemaking as a theoretical perspective to deepen our knowledge and understanding of employees’ behavior within a socially responsible company.

Aim The aim of this study is to illustrate, with a comparative approach, what meaning employees have given to their employer’s social responsibility to provide an understanding of the significance of employers’ various approaches to social responsibility for the social identity, organizational engagement and motivation of employees.

Methodology The research design is a comparative case study. A qualitative methodology was used with an iterative approach, although the initial approach was deductive. The empirical data was gathered through three semi-structured interviews with employees on each company.

Conclusions Employees consider that the purpose of their employer’s social responsibility is to fulfill their need to belong to a company that does good for other stakeholders. Employees’ motivation and organizational commitment may be derived from their employer’s social responsibility if the employees themselves consider these activities important. This is explained by congruence between the individual’s social identity, the employer’s organizational identity and the underlying values of these identities.

Nyintroduktioner och finansiella nyckeltal i låg och högkonjunktur: En studie i huruvida nyintroducerade bolag har åtskiljande nyckeltal i olika konjunkturlägen2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Previous studies shows that a larger number of IPO:s take place during periods of economic expansion compared to periods of economic recession. This paper focuses on studying this phenomena on the two largest marketplaces for stock trading in Sweden: First North and Nasdaq Stockholm. During the economic expansion 2014-2016 the two marketplaces had a record number of IPO:s even though the Swedish economy historically has been better. This paper investigates this market abnormality but also compares IPO:s throughout both economic recessions as well as expansions throughout the years 2007-2016. With the help of prospectuses, interim and annual reports the IPO companies financial key figures have been calculated and then investigated for potential connections to the state of the economy. The study is mostly directed at investors, who through the results of this paper can gain information about the valuation of IPO:s. This is something that currently is of large interest because of the stock markets increasingly popularity. By evaluating the IPO companies and their quality, an indirect valuation of the risk associated with the introduction market is also presented. This can also be useful for investors and can ease the valuation of the current risk as well as the current investment possibilities that are associated with the market for IPO companies.

The result in this study shows that the key figures EV/EBITDA and RE have the greatest connection to the state of the economy. The other key figures P/S, RT, operating margin and equity ratio did not have a clear connection to the state of the economy. The only key figure with major differences exclusively associated with the IPO companies of 2016 was shown to be P/S, which had a substantially higher value compared to the rest of the years. It is therefore concluded that the last years high quantity of IPO:s cannot exclusively be explained by significant differences in the financial key figures of IPO companies. The result indicates that other factors such as the low market interest rates and the IPO companies limited opportunities of borrowing affects the number of IPO:s.

Jämförelsegruppens påverkan på relativvärderingens prediktionsförmåga2017Independent thesis Advanced level (degree of Master (One Year)), 240 HE creditsStudent thesis

Background: The choice of peer group is essential to be able to achieve an accurate relative valuation. Despite this, there are few studies on the subject. This study aims to analyze how the peer group effect the estimation accuracy and if fundamental warranted multiples estimated through regression analysis results in a more accurate estimation than other strategies for estimating the warranted multiple.

Purpose: The purpose of this study is to analyze and examine the peer group’s effect on relative valuation’s estimation accuracy when valuating listed companies.

Methodology: This study takes stamp from existing research in the relative valuation area and has a quantitative strategy with a deductive approach. The dataset has been analyzed through bivariate, OLS regression and panel data analysis to examine the peer group’s effect on the relative valuation estimation accuracy. The study has been conducted from the first quarter 2012 to the last quarter 2016.

Conclusion: The results show that the peer group has a significant impact on the estimation accuracy. Relative valuation based on warranted multiples estimated through regression analysis offers the highest estimation accuracy for all types of multiples included in the study. The results also show that the choice of peer group has a higher impact on the estimation accuracy when estimating a multiple with greater dispersion and that the estimation accuracy does not change significantly over a shorter time period after the time of the valuation.

• Linköping University, Department of Computer and Information Science, The Division of Statistics and Machine Learning.
Linköping University, Department of Computer and Information Science, The Division of Statistics and Machine Learning.
Klassificering av vinkvalitet2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

The data used in this paper is an open source data, that was collected in Portugal over a three year period between 2004 and 2007. It consists of the physiochemical parameters, and the quality grade of the wines.

This study focuses on assessing which variables that primarily affect the quality of a wine and how the effects of the variables interact with each other, and also compare which of the different classification methods work the best and have the highest degree of accuracy.

The data is divided into red and white wine where the response variable is ordered and consists of the grades of quality for the different wines. Due to the distribution in the response variable having too few observations in some of the quality grades, a new response variable was created where several grades were pooled together so that each different grade category would have a good amount of observations.

The statistical methods used are Bayesian ordered logistic regression as well as two data mining techniques which are neural networks and decision trees.

The result obtained showed that for the two types of wine it is primarily the alcohol content and the amount of volatile acid that are recurring parameters which have a great influence on predicting the quality of the wines.

The results also showed that among the three different methods, decision trees were the best at classifying the white wines and the neural network were the best for the red wines.

• Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
Optimization model to improve the planning of a mobile abattoir2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

Today the planning of the transports at Hälsingestintan is done without any tools. Every year the problem regarding the planning is getting more complex and complicates the logistics of the transports. The purpose with the study is to investigate the logistics related to the mobile abattoir and the refrigerated truck in Hälsingestinans process flow. This is relevant due to identify if an optimization model has potential to reduce the transport costs when using this concept. Furthermore, the difference between the used planning strategies of the model and Hälsingestintan will be compared to identify if there are any clear differences between the methods.

• Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
An Analysis of Passenger Demand Forecast Evaluation Methods2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

In the field of aviation forecasting is used, among other things, to determine the number of passengers to expect for each flight. This is beneficial in the practice of revenue management, as the forecast is used as a base when setting the price for each flight. In this study, a forecast evaluation has been done on seven different routes with a total of 61 different flights, using four different methods. These are: Mean Absolute Scaled Error (MASE), Mean Absolute Percentage Error (MAPE), Tracking Signal, and a goodness of fit test to determine if the forecast errors are normally distributed. The MASE has been used to determine if the passenger forecasts are better or worse than a naïve forecast, while the MAPE provides an error value for internal comparisons between the flights. The Tracking Signal and the normal distribution test have been used in order to determine whether a flight has bias or not towards under- or overforecasting. The results point towards a general underforecast across all studied flights. A total of 89 % of the forecasts perform better than the naïve forecast, with an average MASE value of 0,78. As such, the forecast accuracy is better than that of the naïve forecast. There are however large error values among the observed flights, affecting the MAPE average. The MAPE average is 38,53 % while the median is 30,60 %. The measure can be used for internal comparisons, and one such way is to use the average value as a benchmark in order to focus on improving those forecasts with a higher than average MAPE. The authors have found that the MASE and MAPE are useful in measuring forecast accuracy and as such the recommendation of the authors is that these two error measures can be used together to evaluate forecast accuracy at frequent intervals. In addition to this there is value in examining the error distribution in conjunction with the Mean Error when searching for bias, as this will indicate if there is systematic error present.

• Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
Innovative communication strategies and modelling of robust sensor functions2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

The aim of this thesis was to create a resilient network, capable of handling link failures without affecting the data flow. This was done by using graph theory and three mathematical models. A generic system was created, on which the models were applied on. The mathematical models were path diversity, edge protection and path restoration. These models were tested to evaluate if they could create a robust system. The models were also compared with each other to obtain the best performing one. It was concluded that it was possible to construct a resilient network using these types of mathematical modelling. It was also concluded that the models provided different results in terms of cost and robustness. The report ends with suggestions on future work of how studies can be conducted to create realistic systems.

• Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
A memorable reading experience with motion graphics2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

Studien omfattar ämnet motion graphics (rörlig grafik) och hur det kan förmedla en skriven text. En textbaserad rörlig grafik togs fram för att undersöka om rörelserna gjorde textinnehållet lättare att minnas och förstå jämfört med att läsa texten statiskt. Skillnader men också likheter gällande korttidsminne och läsupplevelse undersöktes genom två testgrupper. Studien visar på att läsarna mindes bättre med motion graphics, att motion graphics i vissa fall kan förmedla en mer positiv och specifik känsloupplevelse. Det framkom också att genom motion graphics så kan läsares fokus flyttas till det visuella uttrycket istället för textens innehåll. Resultatet visade även på risken att motion graphics i vissa fall kan göra det svårare för läsaren att minnas textordningen. Det gick inte att helt säkert fastställa om skillnaderna i studien berodde på att rörelserna i sig förstärkte budskapet eller en annan orsak såsom läshastighet alternativt en kombination av flera bidragande faktorer.

• Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
Planning of joint resources - a case study at Seldingerenheten at Linköping University Hospital2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

I och med ett ökat vårdbehov i samhället ställs det utöver medicinska krav också krav på att svensk sjukvård ska öka effektiviteten i sina vårdprocesser. Denna studie utfördes på Seldingerenheten som tillhör den Kardiologiska kliniken vid Universitetssjukhuset i Linköping. På Seldingerenheten utförs behandling av hjärt- och kärlsjukdomar med avancerad kateterteknik i specialutrustade labb. Utöver labben finns det en övervakningsavdelning där patienter som ska behandlas i labben kan få för- och eftervård. Arbetet på Seldingerenheten är uppdelat efter olika sektioner beroende på vilken typ av hjärt- och kärlsjukdom som behandlas. Det finns övergripande planeringsgrupper som planerar på en mer strategisk (långsiktig) nivå medan den mer specifika planeringen på övervakningsavdelningen sker uppdelat efter de olika sektionerna. Tanken med studien var att presentera vilken planering som borde göras på de olika nivåerna samt hur dessa kan integreras med varandra. Varje sektion planerar idag sitt eget patientflöde och bokar in patienter för behandling i labben. När en patient ska behandlas i labben krävs för- och eftervård som antingen kan ske på någon vårdavdelning om patienten är inneliggande eller på övervakningsavdelningen för dagsjukvård. Hur patienter bokas in påverkar därmed patientflödet på dessa vårdavdelningar. Att det inte finns någon gemensam planering eller ett verktyg där de olika sektionerna kan se när patienter är inbokade på Seldingerenheten leder till ett ojämnt patientflöde på övervakningsavdelningen. Studiens resultat visade på ett flertal olika åtgärder som kan tas för att skapa ett jämnare patientflöde och en mer hållbar arbetsmiljö på övervakningsavdelningen. De teorier som åtgärdsförslagen baserats på visar att den negativa effekten av ett ojämnt patientflöde kan minskas genom att antingen påverka patientflödet och dess variation eller genom att vidta åtgärder på övervakningsavdelningen för att hantera situationen som den är.

• Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
Real-time rendering of subsurface scattering and skin2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

Rendering of skin and translucent materials as a real-time solution for a game engine.

• Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
Real-time visualization of a digital learning platform2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

This master thesis report presents the development and results of a dashboard developed for Sanoma Utbildning. The learning platform, called SUD - Sanoma Utbildnig Digital, is a combination of exercises and reading material used by both students and teachers. The purpose of the application is to provide Sanoma Utbildning with valuable insights of the activity in SUD and was developed using agile methods. The dashboard should be easy to understand for both employees at Sanoma Utbildning and possible customers. The user interface has been developed with help from theory and by conducting three user evaluations. The data is collected from logs produced by SUD and sent with webhooks to the dashboard. The result is a web based MEAN-stack application visualizing real time data and statistical data of the events in the learning platform.

• Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
Telepresence and remote communication through virtual reality2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

This Master Thesis concerns a telepresence implementation which utilizes state-of-the-art virtual reality combined with live 360 degree video. Navigation interfaces for telepresence with virtual reality headsets were developed and evaluated through a user study. An evaluation of telepresence as a communication media was performed, comparing it to video communication. The result showed that telepresence was a better communication media than video communication.

• Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
Evaluation of cloud-based infrastructures for scalable applications2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

The usage of cloud computing in order to move away from local servers and infrastructure have grown enormously the last decade. The ability to quickly scale capacity of servers and their resources at once when needed is something that can both be a price saver for companies and help them deliver high end products that will function correctly at all times even under heavy load to their customers. To meet todays challenges, one of the strategic directions of Attentec, a software company located in Linköping, is to examine the world of cloud computing in order to deliver robust and scalable applications to their customers. This thesis investigates the usage of cloud services in order to deploy scalable applications which can adapt to usage peaks within minutes.

• Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
Visualizing Realtime Depth Camera Configuration using Augmented Reality2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

A Time-of-Flight camera from SICK IVP AB is used to monitor a region of interest which implies that the camera has to be configured, it has to be mounted correctly and be aware of the region of interest. Performing the configuration process currently induce the user to manage the captured 3-Dimensional data in a 2-Dimensional environment which obstructs the process and possibly causes configuration errors due to misinterpretations of the captured data. The aim of the thesis is to investigate the concept of using Augmented Reality as a tool for facilitating the configuration process of a Time-of-Flight camera and evaluate if Augmented Reality enhances the understanding for the process. In order to evaluate the concept, a prototype application is developed. The thesis report discusses the motivation and background of the work, the implementation as well as the results.

• Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, The Institute of Technology.
The possibilities and risks of values-based marketing2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

Studien undersöker möjligheterna med syftesdriven marknadsföring för att stärka ett varumärke och bidra till ett ekonomiskt, socialt och miljömässigt hållbart samhälle samt riskerna för att möta opposition eller skada varumärket. Syftesdriven marknadsföring är en term som har vuxit fram inom den svenska kommunikationsbranschen under de senaste åren och har grundidén att företag ska bidra till ett mer hållbart samhälle genom att kommunicera sina värderingar utifrån deras värdegrund. Syftesdriven marknadsföring har hyllats för att den lyfter upp viktiga samhällsfrågor samtidigt som den har kritiserats för att utnyttja viktiga samhällsfrågor i ett försäljningssyfte. Studien baseras på sex stycken kvalitativa intervjuer med personer inom Sveriges PR-­‐‑ och marknadsföringsbransch, samt tidigare marknadsföringsteorier. Resultatet visar att det går att använda syftesdriven marknadsföring för att skapa ett mer hållbart samhälle och stärka ett varumärke om kommunikationen är grundad i företagets kunskap, värderingar och handlingar och därmed arbetas med långsiktig. Just nu finns det ett intresse hos konsumenter för värderingar och hållbarhet vilket gör att just den här typen av marknadsföring kan vara lönsam. Om ett företag däremot inte grundar marknadsföringen i sin egen organisation utan bara har syftet att öka sin egen vinst kommer den inte vara effektiv för varken företag eller samhällets hållbarhet.

• Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
Lektionsplanering i matematik och hypotetiska utvecklingsbanor: En intervjustudie med gymnasielärare2017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis

Studien analyserar tre gymnasielärares planering inför en matematiklektion om polynomekvationer av högre grad för gymnasiekursen matematik 4. Lärarna intervjuas vid ett tillfälle inför lektionen och vid ett tillfälle efter lektionen. Utifrån den första intervjun uttolkas lektionens mål och vilka förkunskaper eleverna förväntas ha. Med målen och elevernas förkunskaper som ramar formuleras en hypotetisk utvecklingsbana för polynomekvationer av högre grad utifrån lärarnas redogörelser under första intervjun. En hypotetisk utvecklingsbana är en möjlig bana för elevers kunskapsutveckling från vissa förkunskaper till ett uppsatt mål. Under den andra intervjun tillfrågas lärarna om utfallet av lektionen överensstämde med deras förväntningar och utifrån intervjun modifieras den hypotetiska utvecklingsbanan. Med en hypotetisk utvecklingsbana som analysverktyg framkommer att lektionens mål är att eleverna minst ska kunna lösa en polynomekvation av fjärde graden och förstå att polynomdivision är en metod för att förenkla en polynomekvation av högre grad till flera ekvationer av lägre grad med hjälp av faktorsatsen. Den hypotetiska utvecklingsbanan innehåller följande aspekter: polynomdivision med liggande stolen då delaren är ett andragradspolynom, omskrivning av vänsterledet i en polynomekvation till en produkt av polynom av lägre grad, lösning av polynomekvationer av grad 3 och 4, lösning av polynomekvationer av alla grader, ansats till lösning genom att gissa en rot, förståelse av den grafiska betydelsen av polynomekvationens rötter, förståelse för och användning av att vissa polynomekvationer har konjugerande rötter och grundläggande förståelse för algebrans fundamentalsats.

• Linköping University, Department of Electrical Engineering, Vehicular Systems.
Linköping University, Department of Electrical Engineering, Vehicular Systems.
Wheel Clearance Testing in a Test Rig Simulation with Operational Chassis Displacement2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis

Volvo Cars proving ground in Hällered is a place for cars to be tested around the clock, in the most rough environments. Testing the wheel clearance today is done by putting modelling clay in the wheelhouse, and then drive through several different obstacles. By doing this, the wheel clearance can be measured where the wheel has left a mark on the modelling clay. The thesis is based on a question if wheel clearance testing can be performed on a test rig, and therefore the issue we decided to work with was what differences in the modelling clay marks could be observed between running the test on the proving ground and simulating the same movement on the test rig. We have made several limitations, the most obvious limit we have chosen is to only focus on the movement in vertical direction.

We used a camera measuring system that was mounted onto our test vehicle. It measures the position from a set origin to the wheel centre in three dimensions over time. We ran tests out on the proving ground, focusing on one obstacle. The test was run for two reasons, to get the imprints from the tire on the clay and to obtain the measurement data from the measuring system. We then identified the maximum reached positive wheel position in vertical direction by using a MATLAB script. We then used the test rig to position the front wheels in the same three-dimensional positions as when the wheel centre reached its maximum vertical value according to the measuring data mentioned above. We measured the imprints of the wheel in the modelling clay after the positioning procedure in the test rig and began to compare the different clay imprints and evaluating the results.

The measurements indicated a significant difference between the two, even though the positioning used in the three dimensions were identical. We discuss the possible reasons for any source of error that we could think of. We also come up with suggestions how to reduce the impact of some of the sources of error.

Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
Completion of Ontologies and Ontology Networks2017Doctoral thesis, comprehensive summary (Other academic)

The World Wide Web contains large amounts of data, and in most cases this data has no explicit structure. The lack of structure makes it difficult for automated agents to understand and use such data. A step towards a more structured World Wide Web is the Semantic Web, which aims at introducing semantics to data on the World Wide Web. One of the key technologies in this endeavour are ontologies, which provide a means for modeling a domain of interest and are used for search and integration of data.

In recent years many ontologies have been developed. To be able to use multiple ontologies it is necessary to align them, i.e., find inter-ontology relationships. However, developing and aligning ontologies is not an easy task and it is often the case that ontologies and their alignments are incorrect and incomplete. This can be a problem for semantically-enabled applications. Incorrect and incomplete ontologies and alignments directly influence the quality of the results of such applications, as wrong results can be returned and correct results can be missed. This thesis focuses on the problem of completing ontologies and ontology networks.

The contributions of the thesis are threefold. First, we address the issue of completing the is-a structure and alignment in ontologies and ontology networks. We have formalized the problem of completing the is-a structure in ontologies as an abductive reasoning problem and developed algorithms as well as systems for dealing with the problem. With respect to the completion of alignments, we have studied system performance in the Ontology Alignment Evaluation Initiative, a yearly evaluation campaign for ontology alignment systems. We have also addressed the scalability of ontology matching, which is one of the current challenges, by developing an approach for reducing the search space when generating the alignment.Second, high quality completion requires user involvement. As users' time and effort are a limited resource we address the issue of limiting and facilitating user interaction in the completion process. We have conducted a broad study of state-of-the-art ontology alignment systems and identified different issues related to the process. We have also conducted experiments to assess the impact of user errors in the completion process.

While the completion of ontologies and ontology networks can be done at any point in the life-cycle of ontologies and ontology networks, some of the issues can be addressed already in the development phase. The third contribution of the thesis addresses this by introducing ontology completion and ontology alignment into an existing ontology development methodology.

1. Completing the is-a structure in light-weight ontologies
Open this publication in new window or tab >>Completing the is-a structure in light-weight ontologies
2015 (English)In: Journal of Biomedical Semantics, ISSN 2041-1480, Vol. 6, 12Article in journal (Refereed) Published
##### Abstract [en]

Background: With the increasing presence of biomedical data sources on the Internet more and more research effort is put into finding possible ways for integrating and searching such often heterogeneous sources. Ontologies are a key technology in this effort. However, developing ontologies is not an easy task and often the resulting ontologies are not complete. In addition to being problematic for the correct modelling of a domain, such incomplete ontologies, when used in semantically-enabled applications, can lead to valid conclusions being missed.

Results: We consider the problem of repairing missing is-a relations in ontologies. We formalize the problem as a generalized TBox abduction problem. Based on this abduction framework, we present complexity results for the existence, relevance and necessity decision problems for the generalized TBox abduction problem with and without some specific preference relations for ontologies that can be represented using a member of the EL family of description logics. Further, we present algorithms for finding solutions, a system as well as experiments.

Conclusions: Semantically-enabled applications need high quality ontologies and one key aspect is their completeness. We have introduced a framework and system that provides an environment for supporting domain experts to complete the is-a structure of ontologies. We have shown the usefulness of the approach in different experiments. For the two Anatomy ontologies from the Ontology Alignment Evaluation Initiative, we repaired 94 and 58 initial given missing is-a relations, respectively, and detected and repaired additionally, 47 and 10 missing is-a relations. In an experiment with BioTop without given missing is-a relations, we detected and repaired 40 new missing is-a relations.

##### National Category
Computer Science Bioinformatics (Computational Biology)
##### Identifiers
urn:nbn:se:liu:diva-116628 (URN)10.1186/s13326-015-0002-8 (DOI)000353197200001 ()25883780 (PubMedID)
##### Funder
Swedish e‐Science Research CenterCUGS (National Graduate School in Computer Science) Available from: 2015-03-29 Created: 2015-03-29 Last updated: 2017-08-21
2. Get my pizza right: Repairing missing is-a relations in ALC ontologies
Open this publication in new window or tab >>Get my pizza right: Repairing missing is-a relations in ALC ontologies
2012 (English)In: Second Joint International Semantic Technology Conference, Springer Berlin/Heidelberg, 2012, 17-32 p.Chapter in book (Refereed)
##### Abstract [en]

With the increased use of ontologies in semantically-enabled applications, the issue of debugging defects in ontologies has become increasingly important. These defects can lead to wrong or incomplete results for the applications. Debugging consists of the phases of detection and repairing. In this paper we focus on the repairing phase of a particular kind of defects, i.e. the missing relations in the is-a hierarchy. Previous work has dealt with the case of taxonomies. In this work we extend the scope to deal with ALC ontologies that can be represented using acyclic terminologies. We present algorithms and discuss a system.

##### Place, publisher, year, edition, pages
Springer Berlin/Heidelberg, 2012
##### Series
Lecture Notes in Computer Science, ISSN 0302-9743 (print), 1611-3349 (online) ; 7774
##### Keyword
ontologies, ontology engineering, ontology debugging, knowledge representation
##### National Category
Computer Science
##### Identifiers
urn:nbn:se:liu:diva-91435 (URN)10.1007/978-3-642-37996-3_2 (DOI)978-3-642-37995-6 (ISBN)978-3-642-37996-3 (ISBN)
##### Funder
Swedish e‐Science Research CenterSwedish Research Council, 2010-4759CUGS (National Graduate School in Computer Science) Available from: 2013-04-24 Created: 2013-04-24 Last updated: 2017-08-21
3. Reducing the search space in ontology alignment using clustering techniques and topic identification
Open this publication in new window or tab >>Reducing the search space in ontology alignment using clustering techniques and topic identification
2015 (English)In: Proceedings of the 8th International Conference on Knowledge Capture, New York: ACM Digital Library, 2015, 21- p.Conference paper, (Refereed)
##### Abstract [en]

One of the current challenges in ontology alignment is scalability and one technique to deal with this issue is to reduce the search space for the generation of mapping suggestions. In this paper we develop a method to prune that search space by using clustering techniques and topic identification. Further, we provide experiments showing that we are able to generate partitions that allow for high quality alignments with a highly reduced effort for computation and validation of mapping suggestions for the parts of the ontologies in the partition. Other techniques will still be needed for finding mappings that are not in the partition.

##### Place, publisher, year, edition, pages
New York: ACM Digital Library, 2015
##### Keyword
Knowledge representation, data mining, ontology alignment
##### National Category
Computer Science
##### Identifiers
urn:nbn:se:liu:diva-121838 (URN)10.1145/2815833.2816959 (DOI)978-1-4503-3849-3 (ISBN)
##### Conference
8th International Conference on Knowledge Capture
##### Funder
CUGS (National Graduate School in Computer Science)Swedish e‐Science Research CenterEU, FP7, Seventh Framework Programme, FP7-IP-608142 Available from: 2015-10-09 Created: 2015-10-09 Last updated: 2017-08-21
4. Experiences from the Anatomy track in the Ontology Alignment Evaluation Initiative
Open this publication in new window or tab >>Experiences from the Anatomy track in the Ontology Alignment Evaluation Initiative
##### Abstract [en]

Background: One of the longest running tracks in the Ontology Alignment Evaluation Initiative is the Anatomy track which focuses on aligning two anatomy ontologies. The Anatomy track was started in 2005. In 2005 and 2006 the task in this track was to align the Foundational Model of Anatomy and the OpenGalen Anatomy Model. Since 2007 the ontologies used in the track are the Adult Mouse Anatomy and a part of the NCI Thesaurus. Since 2015 the data in the Anatomy track is also used in the Interactive track of the Ontology Alignment Evaluation Initiative.

Results: In this paper we focus on the Anatomy track in the years 2007-2016 and the Anatomy part of the Interactive track in 2015-2016. We describe the data set and the changes it went through during the years. Further, we give an overview of all systems that participated in the track and the techniques they have used. We discuss the performance results of the systems and summarize the general trends.

Conclusions: About 50 systems have participated in the Anatomy track. Many different techniques were used. The most popular matching techniques are string-based strategies and structure-based techniques. Many systems also use auxiliary information. The quality of the alignment has increased for the best performing systems since the beginning of the track and more and more systems check the coherence of the proposed alignment and implement a repair strategy.Further, interacting with an oracle is beneficial.

##### Keyword
ontologies, ontology matching, OAEI, anatomy
##### National Category
Computer Science
##### Identifiers
urn:nbn:se:liu:diva-139775 (URN)
##### Funder
Swedish e‐Science Research CenterCUGS (National Graduate School in Computer Science)EU, FP7, Seventh Framework Programme, FP7-IP-608142 Available from: 2017-08-21 Created: 2017-08-21 Last updated: 2017-08-21
5. User validation in ontology alignment
Open this publication in new window or tab >>User validation in ontology alignment
2016 (English)In: The Semantic Web – ISWC 2016: 15th International Semantic Web Conference, Kobe, Japan, October 17–21, 2016, Proceedings, Part I / [ed] Paul Groth, Elena Simperl, Alasdair Gray, Marta Sabou, Markus Krötzsch, Freddy Lecue, Fabian Flöck and Yolanda Gil, Cham, Switzerland: Springer Publishing Company, 2016, 200-217 p.Chapter in book (Refereed)
##### Abstract [en]

User validation is one of the challenges facing the ontology alignment community, as there are limits to the quality of automated alignment algorithms. In this paper we present a broad study on user validation of ontology alignments that encompasses three distinct but interrelated aspects: the profile of the user, the services of the alignment system, and its user interface. We discuss key issues pertaining to the alignment validation process under each of these aspects, and provide an overview of how current systems address them. Finally, we use experiments from the Interactive Matching track of the Ontology Alignment Evaluation Initiative (OAEI) 2015 to assess the impact of errors in alignment validation, and how systems cope with them as function of their services.

##### Place, publisher, year, edition, pages
Cham, Switzerland: Springer Publishing Company, 2016
##### Series
Lecture Notes in Computer Science, ISSN 0302-9743 (print), 1611-3349 (online) ; 9981
##### Keyword
knowledge representation, user interfaces, ontology engineering, ontology alignment
##### National Category
Computer Science
##### Identifiers
urn:nbn:se:liu:diva-131806 (URN)10.1007/978-3-319-46523-4_13 (DOI)000389086500013 ()9783319465227 (ISBN)9783319465234 (ISBN)
##### Funder
Swedish e‐Science Research CenterCUGS (National Graduate School in Computer Science)EU, FP7, Seventh Framework Programme, FP7-IP-608142 Available from: 2016-10-07 Created: 2016-10-07 Last updated: 2017-08-21Bibliographically approved
6. Integrating Ontology Debugging and Matching into the eXtreme Design Methodology
Open this publication in new window or tab >>Integrating Ontology Debugging and Matching into the eXtreme Design Methodology
2015 (English)In: Proceedings of the 6th Workshop on Ontology and Semantic Web Patterns (WOP 2015) / [ed] Eva Blomqvist; Pascal Hitzler; Adila Krisnadhi; Tom Narock; Monika Solanki, Rheinisch-Westfaelische Technische Hochschule Aachen University , 2015Conference paper, (Refereed)
##### Abstract [en]

Ontology design patterns (ODPs) and related ontology development methodologies were designed as ways of sharing and reusing best practices in ontology engineering. However, while the use of these reduces the number of issues in the resulting ontologies defects can still be introduced into the ontology due to improper use or misinterpretation of the patterns. Thus, the quality of the developed ontologies is still a major concern. In this paper we address this issue by describing how ontology debugging and matching can be integrated in a state-of-the-art ontology development methodology based on ontology design patterns- the eXtreme Design methodology, and show the advantages in a case study based on a real world ontology.

##### Place, publisher, year, edition, pages
Rheinisch-Westfaelische Technische Hochschule Aachen University, 2015
##### Series
CEUR Workshop Proceedings, ISSN 1613-0073 ; 1461
##### National Category
Media and Communication Technology
##### Identifiers
urn:nbn:se:liu:diva-121794 (URN)
##### Conference
6th Workshop on Ontology and Semantic Web Patterns (WOP 2015), Bethlehem, Pensylvania, USA, October 11, 2015
##### Funder
EU, FP7, Seventh Framework Programme, FP7-IP-608142CUGS (National Graduate School in Computer Science)Swedish e‐Science Research Center Available from: 2015-10-06 Created: 2015-10-06 Last updated: 2017-08-21Bibliographically approved
• Linköping University, Department of Computer and Information Science, The Division of Statistics and Machine Learning.
Linköping University, Department of Computer and Information Science, The Division of Statistics and Machine Learning.
En utvärdering av reliabilitet och mätinvarians hos ett självtest för spelberoende2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

GamTest är ett självtest för tidiga indikationer på spelberoende som är utvecklat av Sustainable Interaction. Testet består av 15 frågor över 5 olika problemdimensioner, denna uppsats fokuserar på att förkorta detta test samt undersöka skillnader mellan exempelvis kön och ålder.

Statistiska metoder som används är Cronbachs alfa, konfirmativ faktoranalys samt olika typer av multigroup-analyser.

Resultatet av analyserna visar att antalet frågor i testet kan förkortas till 13 stycken utan att tillförlitligheten förändrades negativt. En modell med 13 frågor visade även på en bättre modellanpassning i den konfirmativa faktoranalysen jämfört med den ursprungliga modellen. Anpassningen förbättras ytterligare med 11 frågor men denna modell har en något lägre reliabilitet. Detta betyder att respondentens tid för testet kan förkortas utan att pålitligheten försämras. Multigroup-analyser visar att spelproblem definieras olika för kön och för ålder.

Flera frågor stämmer överens med de som finns i ett annat välkänt mätinstrument för spelproblem, Problem Gambling Severity Index, men i GamTest finns frågor som handlar om problem med konsumtion i tid vilket saknas i det förstnämnda. Överlag så är testen annars väldigt lika.

• Linköping University, Department of Computer and Information Science, The Division of Statistics and Machine Learning.
Linköping University, Department of Computer and Information Science, The Division of Statistics and Machine Learning.
Mönster som leder till sjukfrånvaro: Sekvensanalys på longitudinella data2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis

Absence due to sickness results in a cost to both employers and employees. For an unnamed wholesaler this is a problem at one of their warehouses, where the rate of sick leave is high. The aim of this thesis is to identify interesting patterns over time that lead to sick leave by analyzing data from the company's payroll system and their attendance system.

The data is longitudinal and to detect the patterns that lead to sick leave, sequence analysis is used. To generate the sequential patterns the algorithm cSPADE is used since it allows time constraints to be specified for the sequences. The relevance of the generated sequences is evaluated with three interest measures: support, confidence and lift.

Three separate analyses are performed where different variables are used, depending on whether they change over time or have a constant value, and for these analyses the data is aggregated weekly. The most common events that lead to sick leave for the employees are different duration of employment, gender and birth year. A few days sick leave during a week, namely between 8 and 40 hours, is more common among the employees compared to shorter and longer sick leave. It can be noted that the pattern of previous sick leave usually leads to continued sick leave.

The thesis also highlights the problems that arise in sequence analysis, for example that the constant variables overshadow the non-constant variables in the resulting sequences. This happens when variables that change over time are used in combination with variables that have a constant value, which may occur in longitudinal data.

• Linköping University, Department of Religion and Culture. Linköping University, Faculty of Arts and Sciences.
Linköping University, Department of Thematic Studies, Health and Society. Linköping University, Faculty of Arts and Sciences. Lärarhögskolan, Stockholm. Lärarutbildningen, Karlstad och Södertörn.
Livstolkning och värdegrund: Att undervisa om religion, livsfrågor och etik2000Book (Other academic)

Skolans värdegrund har på senare år lyfts fram i många olika sammanhang. Uppgiften att undervisa om religion, etik, och livsfrågor har också debatterats. Detta undervisningsområde hör till skolans svåraste uppgifter - men kanske också till de viktigaste. Denna antologi ger ett bidrag till utvecklingen av ett professionellt lärarkunnande i frågor som gäller skolans värdegrund och undervisning på livsåskådningsområdet.

Författarna ger utifrån sina respektive kompetensområden en belysning av några av ämnesområdets centrala aspekter.

De texter som ingår har skrivits särskilt för lärarutbildningen men kan också användas i andra sammanhang. Avsikten har varit att via texterna föra de studerande i kontakt med såväl aktuell forskning som professionell lärarkunskap av annat slag.

• Linköping University, Department of Behavioural Sciences and Learning.
"It's not like someone hands you a brochure": A qualitative study of migrant mothers' perceptions of their learning at Swedish open preschools2017Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis

Times of transition can provoke informal learning that is both potentially transformative and often unacknowledged. New mothers living in a new country are in effect undergoing a double transition, and thus are in a position to possibly undertake a great deal of informal learning. This research focuses on migrant mothers living in Sweden and aims to understand their perceptions of their own learning at open preschools (öppna förskolor), or drop-in centers for young children and their caretakers. Through a small-scale qualitative study using semi-structured interviews, eight migrant mothers living in Solna municipality shared their memories and opinions about open preschools. The data was analyzed using thematic analysis and examined in light of Wenger’s (1998) social theory of learning and community of practice framework. The mothers overwhelmingly identified open preschools as places of support, with some also perceiving them as places of learning. Nonetheless, the findings show a great deal of informal learning related to mothering and mothering in a new country. There was a complicated relationship between supports and barriers to learning, reflecting the nuanced nature of communities of practice. In short, open preschools gave the participants a place to engage on their own terms with the intellectual work involved with forming their identities as migrant mothers. They also, however, encouraged the development of mothering identities that are in line with dominant Swedish discourses about gender and childrearing. This study proposes nevertheless that open preschools play a vital role in supporting parental learning and easing the transition to life in Sweden for migrant mothers.

• Linköping University, Department of Electrical Engineering, Communication Systems.
Cell Acquisition and Synchronization for Unlicensed NB-IoT2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

Narrowband Internet-of-Things (NB-IoT) is a new wireless technology designed to support cellular networks with wide coverage for a massive number of very cheap low power user devices. Studies have been initiated for deployment of NB-IoT in unlicensed frequency bands, some of which demand the use of a frequency-hopping scheme with a short channel dwell time. In order for a device to connect to a cell, it must synchronize well within the dwell time in order to decode the frequency-hopping pattern. Due to the significant path loss, the narrow bandwidth and the device characteristics, decreasing the synchronization time is a challenge. This thesis studies different methods to decrease the synchronization time for NB-IoT without increasing the demands on the user device. The study shows how artificial fast fading can be combined with denser reference signalling in order to achieve improvements to the cell acquisition and synchronization procedure sufficient for enabling unlicensed operation of NB-IoT.

• Linköping University, Department of Computer and Information Science.
Linköping University, Department of Computer and Information Science.
Counting the clicks on Twitter: A study in understanding click behavior on Twitter2017Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis

Social media has a large impact on our society. News articles are often accessed and shared through different social media sites . In fact, today the most common way to enter a website is from social medias. However, due to technical restrictions in what information these sites make public, it is often not possible to access click information from social medias. This complicates the analysis of popularity dynamics of news articles, for example. In this thesis, we work around that problem. By using an URL shortener service API, we can extract information about the clicks from the API. We will only look at content that is shared on Twitter because they have the friendliest view on sharing data for research purposes. To test this methodology we are doing a small prestudy in which we look at how biased news articles are shared on Twitter compared to more objective content. There are three parts in investigating the biased content. The first part is to extract Bitly links from Twitter. The second part is to examine the links and decide if it is a news article. Finally, we determine if the news article is biased. For this third step, we use two different approaches. First, we build a computational linguistics tool called a Naive Bayes classifier from already classified training data. Second, we classify different articles as articles with biased content or not, where an article is considered biased if the domain it resides on has a high content of biased articles. Our analysis of a sample data set that we have collected over a week showed that biased content is clicked for a longer period of time compared to non-biased content.

• Public defence: 2017-09-15 10:15 Planck, Fysikhuset, Linköping
Linköping University, Department of Physics, Chemistry and Biology, Surface Physics and Chemistry. Linköping University, Faculty of Science & Engineering.
Electrokinetic devices from polymeric materials2017Doctoral thesis, comprehensive summary (Other academic)

There are multiple applications for polymers: our bodies are built of them, plastic bags and boxes used for storage are composed of them, as are the shells for electronics, TVs, computers, clothes etc. Many polymers are cheap, and easy to manufacture and process which make them suitable for disposable systems. The choice of polymer to construct an object will therefore highly influence the properties of the object itself. The focus of this thesis is the application of commonly used polymers to solve some challenges regarding integration of electrodes in electrokinetic devices and 3D printing.

The first part of this thesis regards electrokinetic systems and the electrodes’ impact on the system. Electrokinetic systems require Faradaic (electrochemical) reactions at the electrodes to maintain an electric field in an electrolyte. The electrochemical reactions at the electrodes allow electron-to-ion transduction at the electrode-electrolyte interface, necessary to drive a current at the applied potential through the system, which thereby either cause flow (electroosmosis) or separation (electrophoresis). These electrochemical reactions at the electrodes, such as water electrolysis, are usually problematic in analytical systems and systems applied in biology. One solution to reduce the impact of water electrolysis is by replacing metal electrodes with electrochemically active polymers, e.g. poly(3,4-ethylenedioxythiophene) (PEDOT). Paper 1 demonstrates that PEDOT electrodes can replace platinum electrodes in a gel electrophoretic setup. Paper 2 reports an all-plastic, planar, flexible electroosmotic pump which continuously transports water from one side to the other using potentials as low as 0.3 V. This electroosmotic pump was further developed in paper 3, where it was made into a compact and modular setup, compatible with commercial microfluidic devices. We demonstrated that the pump could maintain an alternating flow for at least 96 h, with a sufficient flow of cell medium to keep cells alive for the same period of time.

The second part of the thesis describes the use of 3D printers for manufacturing prototypes and the material requirements for 3D printing. Protruding and over-hanging structures are more challenging to print using a 3D printer and usually require supporting material during the printing process. In paper 4, we showed that polyethylene glycol (PEG), in combination with a carbonate-based plasticizer, functions well as a 3D printable sacrificial template material. PEG2000 with between 20 and 30 wt% dimethyl carbonate or propylene carbonate have good shear-thinning rheology, mechanical and chemical stability, and water solubility, which are advantageous for a supporting material used in 3D printing.

The advances presented in this thesis have solved some of the challenges regarding electrokinetic systems and prototype manufacturing. Hopefully this will contribute to the development of robust, disposable, low-cost, and autonomous electrokinetic devices.

1. Conducting Polymer Electrodes for Gel Electrophoresis
Open this publication in new window or tab >>Conducting Polymer Electrodes for Gel Electrophoresis
2014 (English)In: PLoS ONE, ISSN 1932-6203, Vol. 9, no 2, 0089416- p.Article in journal (Refereed) Published
##### Abstract [en]

In nearly all cases, electrophoresis in gels is driven via the electrolysis of water at the electrodes, where the process consumes water and produces electrochemical by-products. We have previously demonstrated that p-conjugated polymers such as poly(3,4-ethylenedioxythiophene) (PEDOT) can be placed between traditional metal electrodes and an electrolyte to mitigate electrolysis in liquid (capillary electroosmosis/electrophoresis) systems. In this report, we extend our previous result to gel electrophoresis, and show that electrodes containing PEDOT can be used with a commercial polyacrylamide gel electrophoresis system with minimal impact to the resulting gel image or the ionic transport measured during a separation.

##### Place, publisher, year, edition, pages
Public Library of Science, 2014
##### National Category
Engineering and Technology
##### Identifiers
urn:nbn:se:liu:diva-105901 (URN)10.1371/journal.pone.0089416 (DOI)000331711900141 ()
Available from: 2014-04-14 Created: 2014-04-12 Last updated: 2017-08-18Bibliographically approved
• Linköping University, Department of Computer and Information Science, Human-Centered systems.
Utveckling av tvådimensionellt online-spel i kategorin action-strategi för smartphones med fokus på spelupplevelse och prestanda2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

Vid utveckling av spel till smartphones så krävs ofta flera olika implementationer för olika plattformar. Men det finns olika spelmotorer och ramverk till olika programspråk som kan kompilera samma kod till flera olika mobila plattformar. Kivy är ett sådant ramverk för programspråket Python.

I detta arbete användes prototypdriven utveckling i Kivy för att försöka höja spelupplevelsen av ett tvådimensionellt online-spel i kategorin action-strategi som tidigare fanns implementerat i GameMaker. Olika tekniker för att öka prestandan för spelet testades också. Det visade sig att med den bästa kombinationen av de tekniker som testades så blev prestandan med hög last cirka 29 bilder/s. Användarbarheten, spelbarheten och ljud-estetiken av spelet ökades medan nöjet och den personliga tillfredställelsen från spelet minskade. Totalt sett blev spelupplevelsen i stort sätt oförändrad.

• Linköping University, Department of Management and Engineering, Political Science. Linköping University, Faculty of Arts and Sciences.
New ways and actors when diplomacy goes digital: The e-Diplomacy Campaign “Midwives4All2017In: Proceedings of the 50th Hawaii International Conference on System Sciences, 2017, Waikoloa: University of Hawaii , 2017, 2438-2447 p.Conference paper (Refereed)

This article focuses on Midwives4All, an e-diplomacy campaign launched by the Swedish MFA in 2015. The campaign aims to spread knowledge about the benefits of midwives and evidence-based midwifery. Within the campaign, the Swedish MFA, and in particular its Communications Department (UD-KOM), combines e-diplomacy and networking and the campaign has become one key activity within the Swedish feminist foreign policy. It is organizing diplomacy in new ways that regards both choices of channels and the networking with inter- and nongovernmental organizations. The limited impacts of the campaign are seen as consequences of the peripheral status of the issue and the lack of systematic structures for e-diplomacy so far. In spite of this the case indicates that e-diplomacy has the potential to raise and empower both new actor groups and new issues on the diplomatic agenda.

• Linköping University, Department of Physics, Chemistry and Biology.
Night, light and flight: Light attraction in Trichoptera2017Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis

Artificial light is an important and necessary part of our urban environment, but has become a threat to biodiversity. It can have substantial direct and indirect effects on populations of all kinds of organisms. While light attraction in bats and moths has been well studied other organisms such as Trichoptera have been largely neglected, despite Trichoptera being one of the most abundant insect orders in freshwater systems. The light attraction of Trichoptera was studied through seasonal data from three different locations in Sweden. The data was examined through meta- and regression analyses to compare catches in light traps and passive traps. The use of relative abundances excluded bias from the species with large populations, and the difference in individuals caught between passive traps and light traps. The results indicated that artificial light could affect Trichoptera populations. Unlike moths, female Trichoptera were more attracted to light than males and attraction to light varied between species. In both cases, size dimorphism could explain the variation. Day-, evening- and night-active species were all attracted to light, but the latter more so. Research has shown that a false flight activity can occur in day-active Trichoptera when a lamp is lit during night, which could explain the capture of day- and evening-active species in a light trap. In all, artificial light could alter Trichoptera populations, changing sex ratios and species composition. This impact should be considered when erecting light sources near waterways.

• Public defence: 2017-09-15 13:15 VAL, Vallfarten, Linköping
Linköping University, Department of Thematic Studies, Technology and Social Change. Linköping University, Faculty of Arts and Sciences.
Gränsdragningar i Vårdens Vardag: Hanteringen av arbetsrelaterad psykisk ohälsa i det svenska välfärdssystemet2017Doctoral thesis, monograph (Other academic)

Mental ill health in working life is a major and growing problem in the welfare society. The problem is multifaceted and raises many questions about who is responsible, what kind of phenomenon it is and how it should be managed. This study examines how care professionals manage work-related mental ill health. Focusing on occupational healthcare and primary care, interest is directed towards how care professionals argue about workrelated mental illness, what dilemmas they face and the strategies they rely on in managing them. It also seeks to answer the question of responsibility regarding this complex problem, not least in the light of the privatization of occupational healthcare.

The study uses a multidisciplinary perspective, combining concepts from technology and science studies (STS), sociology of professions and organizational theory in order to analyze various aspects of care management of work-related mental ill health. The empirical material is mainly based on interviews with physicians, psychotherapists, counsellors, occupational therapists, psychologists, rehabilitation coordinators and behavioral scientists, but also includes observations in primary care and occupational health care. The management of work-related mental ill health in everyday healthcare practice is characterized by the fact that the cause of the problem is complex, the division of responsibility unclear and that psychosocial causes of disease are controversial. The study discusses the challenges and possibilities of managing this complex problem in a broad sense. The analysis pays attention to the drawing of boundaries by the care professionals regarding both responsibility and the phenomenon of work-related mental illness. The concept of knowledge infrastructure is used to explain and understand the knowledge and material structures that the care professionals work within. The analysis shows that the care professionals have a pragmatic approach and use different strategies to create scope for dealing with work-related mental health.

• Linköping University, Department of Computer and Information Science.
Investigating the Social Influence of Different Humanoid Robots2017Independent thesis Basic level (degree of Bachelor), 12 credits / 18 HE creditsStudent thesis

The aim with this thesis were to investigate social influence of the two humanoid robots, NAO and Pepper. The research questions were if there were a difference in human social acceptance, in social influence and in influence on human decision making between NAO and Pepper.

To answer these questions, an experiment using the Wizard of Oz-method were used with 36 participant, 18 in each group, interacted with NAO or Pepper. Afterwards two questionnaires, NARS and GODSPEED, were answered and an additional interview were held with the participants.

The result showed a significant difference on GODSPEED, where NAO indicates to have a higher amount of social influence on the participants then Pepper. The result for NARS were not significant. The result from the decisions made during the experiment indicated that humans follow NAO more than Pepper, a result that got more explained and understandable during the interviews.

For future studies there would be interesting to test the scenario with a larger selection and also with a more natural Wizard of Oz-design.

Resan mot den virtuella verkligheten: En multipel fallstudie av den virtuella verklighetens påverkan på varumärkesimagen inom bilindustrin2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Purpose The purpose of this study is to investigate how companies can use VR-commercials and commercials to influence brand image. Furthermore, the purpose is to identify which factors in these medias that affect brand image as well as account for the differences between these two medias.

Research questions How can companies use VR-commercials and commercials to influence brand image? Which factors affect brand image through VR-commercials and commercials and what is the differences between these two medias?

Result VR-commercials and commercials make it possible to influence the brand image. The essay also mentions the identified factors that affect the brand image which are environment, telepresence, memories and associations, noise and disturbances, barriers and music.

Contribution The study describes how companies can use VR-commercials and commercials to influence an individual's brand image. The study clarifies the differences between the two medias and the factors that influence the brand image of the interviewees. An analysis model is presented since a gap in the existing knowledge in communications theory was discovered

Kan jämställdhet vara en möjlighet?: Hur användning av Femvertising påverkar varumärkesimage2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Background: The spreading of feminist messages and the celebration of women's diversity has led to the emergence of a new category of marketing called Femvertising. There is an uncertainty about how advertising that employs this category is perceived by consumers, making it interesting to investigate whether consumers' attitudes and associations connected with a brand are affected using Femvertising.

Purpose: In this master thesis the relation between Femvertising and Brand Image is examined. The purpose of the study is to investigate how the perception of a Brand Image in terms of Brand Personality, brand attitude and attitude towards the ad is affected by exposure to Femvertising according to young consumers. Furthermore, an identification will be made of the differences between young male and female consumers regarding the mentioned subject.

Method: The study is based on a quantitative method with a deductive approach, where the data collection took place in the form of an experiment with a subsequent survey. In order to answer the research questions, the collected data was processed in Excel and SPSS.

Conclusion: The study has identified that the use of Femvertising leads to a Brand Image characterized by sincerity by young consumers. Young consumers have positive attitudes both to the advertisement and the brand, but the perception of a Brand Image cannot be expected to differ between young women and men when using Femvertising. Young women present more positive attitudes both towards the advertisement and the brand in comparison with young men, but it should be emphasized that Femvertising also has positive effects on brand image according to young men.

Hur kan Sustainability Management Control Systems användas för att integrera hållbar utveckling inom banksektorn?2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Sustainable development is a topical subject in today's society and there is an increasing demand for companies to take responsibility by contributing to sustainable development. The banks control how capital is invested, thus giving them great power to and a lot to gain from promoting sustainable development in society. The business opportunities from the market for sustainable development is estimated to provide a value of three trillion dollars annually by 2050. Banking on shared value ​​(BSV), which is a further development of creating shared value, means that banks can generate economic value and at the same time create social and environmental value. A review conducted by Fair Finance Guide shows that the seven largest banks in Sweden are performing relatively low results in terms of sustainability.

Many researchers argue that sustainability management control systems (SMCS), which is a developed model of Malmi and Brown's theory about MCS, can be the key to successfully integrating sustainable development into the business. However, more practical cases are required in the area. This study aims at contributing to an increased understanding of how corporate governance in the banking sector can use SMCS to integrate sustainable development into the business.

A case study has been carried out on Ekobanken, which is the only Swedish bank that is a member of Global Alliance for Banking on Values and has been awarded the highest rating in the Fair Finance Guide´s review. The empirical material has been collected by means of semi-structured interviews with two persons within Ekobanken´s management team as well as documentary studies. The study has an abductive approach.

We have identified Ekobanken's most prominent management tools as cultural governance with a strong focus on sustainable development, administrative governance and cybernetic management tools. In our opinion Ekobanken has a successful SMCS that manage to integrating sustainable development into the business. However, Ekobanken's work with sustainable development can, in our opinion, not be fully defined as BSV, but we believe that they are the bank in Sweden that is currently closest to meeting the requirements for BSV. Therefore we mean that the results of this study can be of inspiration for other banks. It is primarily Ekobanken's transparency, open climate, management's commitment, and their sustainability report and lending policy that other banks working towards sustainable development should strive to apply.

P/B i kombination med marknadsvärde: En studie på Stockholmsbörsen 2006 - 20162017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Background: This study is a test of an investment strategy based on relative valuation of multiples. The multiple to be studied is Price-to-Book (P/B). P/B is chosen because although previously researched, the implications of book values paired with market values are still not well understood.

Aim: The aim of this study is to examine and analyze the multiple P/B as an investment strategy for stocks. Moreover, this study intends to examine stocks with low and high P/B: s from the Small, Mid and Large Cap on the Stockholm Stock Exchange.

Completion: Six portfolios are created based on low and high P/B: s respectively from the market value-based stock exchange lists Small, Mid and Large Cap on the Stockholm Stock Exchange. The portfolios are rebalanced annually and are followed between 2006 and 2016.

Results: Four out of six portfolios exhibit higher levels of cumulative returns than the chosen stock index before and after adjusting for risk. However, weak statistical evidence prevent conclusive showings of excess returns over time. Similarly, we find weak support for differences in returns between low and high P/B: s. Neither does there seem to exist significant differences in return and risk between the Small, Mid and Large Cap.

Teknik i klädesbutik: Upplagt för kritik eller snillerikt?2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Background The apparel industry faces new possibilities in the form of selfservice technology (SST). Several stores have already started using different types of technological solutions. There seem to be a disagreement regarding whether or not this is a good idea to implement SST in all types of apparel stores.

Purpose The purpose of this study is to create a deeper understanding regarding Swedish consumers decision making styles and their technology readiness and how this enables the use of SST in apparel stores.

Completion After an extensive literature review a survey was created. The survey was based on well established tools for measuring consumer decision making styles and technology readiness. The survey was distributed in Linköping, Sweden and then analyzed in SPSS.

Conclusion Swedish consumers have different consumer decision making styles and different levels of technology readiness. The study showed that it was possible to divide the consumers into four different groups regarding consumer decision making style. The consumers classified as habitual and brand loyal and shopping avoiders showed high levels of technology readiness, the enabling of SST for this type of consumer seems promising. The shopping lover and the confused shopper enabling of SST seems less promising since they show low levels of technology readiness.

Total Kvalitetsstyrning inom Non-Big X Revisionsbyråer: Praktiskt arbete med ISQC 12017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Background and problem: The Enron scandal is one of many audit scandals during the 21st century, which in combination with the global harmonization has led to increased demands on the audit sector and its quality. Due to this the ISQC 1 was designed, which purpose is to control and guide an internal quality control that will achieve and maintain a high level of quality. Research on audit quality has risen with the designing of ISQC 1, where focus mostly have been on how audit firms have managed the implementation of and the work with the standard. However, the research focuses on big international audit firms, which results in audit firms with a lower number of employees being left in the dark. The established field of Total Quality Management can be used to study how audit firms with a lower number of employees work with ISQC 1.

Purpose: The purpose of this study is to create an understanding of how non-Big X audit firms use ISQC 1 to assure the quality of their services.

Method: This study uses a qualitative method and an inductive approach, with elements of a deductive approach. Empirical primary data has been gathered by longer semi-structured interviews with eight auditors who all works on different non-Big X audit firms. A content analysis has also been executed, which compares ISQC 1 with the cornerstones of TQM.

Conclusion: This study indicates that non-Big X audit firms mostly uses meetings, teachings and audit manuals to create a quality culture and work as a basis for the audit process. Furthermore, the study implies that ISQC 1 is experienced as resource-demanding, copious and more adjusted to big international audit firms. To face these issues, this study indicates that a cooperation with audit networks can help. When it comes to audit firms assuring the quality of their services, this study points out that preventing errors is critical for the non-Big X audit firms. Ultimately this study supports that there is an expectation gap, and that customers demand different things than what ISQC 1 advocate.

Konsensus - en fundamental osanning?: En studie om aktiemarknadspsykologins påverkan på aktieanalytiker som bidrar till konsensus samt problematiken som medföljer2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Background: To explain certain events that transpires on the stock market a lot of scientists use behavioral finance. They use this due to the fact that the market participants are human after all. Consensus estimates is the compiled estimates of sell side analyst which is supposed to be equivalent to the markets fundamental expectations. The fact that sell side analysts are human infers that they also get influenced by psychology, which in turn affect consensus, investors and lastly the market. Purpose: The purpose of this paper is to analyze and shed light on the elements that affect consensus estimates to clarify how stock market participants can relate to them. The focus will be on elements that, unlike fundamental and technical analysis, originates from behavioral finance. Method: Ten different stock analysts have been interviewed with a qualitative research approach. The interviews then acted as a basis for the analysis where the theory, originating from behavioral finance, is used to come to a conclusion. Conclusion: In conclusion, the result exhibits proof that consensus estimates doesn’t, to a full extent, truly reflect the sell side analysts’ true beliefs. Investors and other stock analysts should therefore relate to consensus as a reference point rather than a guideline for investment decisions.

Asset Liability Management: Ur privatpersonens perspektiv: Ta kontroll över din ekonomiska framtid2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

BACKGROUND: Companies and financial institutions have developed advanced tools based on the theories of Asset Liability Management with purpose to proactively manage risks and plan future cash flows. At the same time, private financial advising of today is still based on traditional asset allocation methodologies and rules of thumbs. Previous research concludes that similar ALM-tools could add value for private investors in the financial advising, but the private investors’ perspective in the matter is still unexplored. The fact remains that only if the private investors are convinced that ALM can add value, can a tool with theoretical advantages be successfully implemented in practice.

AIM: The aim of this thesis is to test and analyze the individual investors’ attitude and capacity to understand private financial advising based on ALM as methodology, and analyze whether an ALM tool adds value in private financial advising.

COMPLETION: The thesis has been conducted by ten individual interviews in a qualitative manner. The authors have created a fictitious ALM-analysis that has been presented for all of the respondents. By asking questions connected to scenarios, the study have been able to analyze the individuals’ attitude to share and receive personal information, as well as their attitude to proactively plan their financial future.

CONCLUSION: The study concludes that the biggest value-creating aspect of ALM is that individuals show a great interest in visualizing their own financial future. However, a financial illiteracy in combination with a lack of clear-cut financial ambitions, weakens the ALM-tools area of use for the individual. Furthermore, ALM need to overcome barriers in individuals limited rational behavior and simultaneously create a strong trust to maximize the value-creation for the individual.

Från policy till praktik: Det systematiska kvalitetsarbetet inom det svenska skolväsendet2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Introduction When implementing a management philosophy into an organization, it needs to be translated into practice in the organizational context. In this interaction between management philosophy and organizational context, problems can arise that may cause the implementation to fail or the meaning of the management philosophy to change during the translation process. The systematic quality work was introduced in the Swedish school system to increase the quality of education, but current surveys show a negative trend in students educational outcomes. This indicates that there may be shortcomings in the current quality management in the school system, hence a study of the translation of the management philosophy from policy to practice is of importance.

Purpose The aim of the study is to contribute to an increased understanding of translation of a management philosophy into practice in public service and to increase understanding of the problems that may occur during the translation process.

Method The study is based on a phenomenological perspective with an iterative approach and consists of a qualitative small-N study. The empirical material has been collected through interviews with seven principals for municipal elementary schools in Uppsala municipality as well as support material for the systematic quality work published by the Swedish National Agency for Education.

Conclusion The study has shown that the principal´s role as translator of the systematic quality work is critical for the organizational practice while the role is characterized by complexity, which leads to problems in the translation process. The complexity can be derived primarily from the organizational context in the form of public service, but also from ambiguity in the management philosophy. Furthermore, the study has identified that openness and flexibility for change is an important translator's competence when translating a management philosophy into organizational practice in public service.

Kooperationens förvaltare: Ett kooperativt perspektiv av agentproblematiken2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Background: Despite its significant presence in today’s society, co-operative businesses still lack well-defined guidelines on how to manage their organizations. Challenges arise because co-operatives, i.e. member-owned organizations, differ in a number of ways compared to other forms of businesses. Still, however, they have to rely on frameworks and theories adapted to other types of organizations. Challenges may develop since it appears as though established management frameworks in many cases are insufficient and difficult to adjust to the objectives that characterize co-operative businesses, which argues for the need of a co-operatively adapted governance framework.

There has been an absence of studies in previous research explaining how agency issues arise, and how the entailing challenges are managed in a co-operative context. At the same time, with the aforementioned lack of governance frameworks, it is nevertheless a challenge for co-operatives to achieve goal congruence between the organization’s various parties, where the size and structure of the organization also play decisive roles.

Purpose: The main purpose of this study is to provide an empirical, as well as a theoretical, contribution to raise the awareness in regards to the Principal-agent problem and its entailing challenges in the context of consumer co-operatives. Furthermore, the purpose is also to investigate how high goal congruence can be achieved in member-owned businesses, without overlooking the interests of the members.

Method: The study was carried out as a qualitative case study of the organization Kooperativa Förbundet, using an iterative approach. The collection of data has been attained through semi-structured interviews, in which the interviews were designed in accordance with the theoretical reference framework.

Conclusions: The Principal-agent problems that arise within co-operatives are primarily of a Stewardship nature. However, our empirical research has highlighted challenges that Stewardship theory previously has not paid any attention to, including those that arise whenhigh levels of trust between the Board of Directors and the Management team lessens the need for follow-ups and evaluations. These challenging issues have resulted in an implementation of control systems, which usually are associated with the contrasting Agency theory, rather than with Stewardship theory. Nevertheless, the introduction of control systems must be done vigilantly, according to Stewardship theory, considering the consequences that may develop, which harmfully may affect the favorable stewardship behavior.

The results from our analysis reveal a high level of goal congruence within the co-operation, owing to a mutual stewardship perspective between the Board of Directors and the Management team. Our research identified a consensus among the respondents in terms of values, and a collective willingness to comply with the co-operative principles. Furthermore, goal congruence is achieved through openness, transparency, justifiable decision-making processes, as well as a continuous dialogue between all parties within the organization. In addition, it was made clear that a high level of goal congruence, other things being equal, does not lead to a successful business. A strong implementing power is also required in order to reach the common goals. The case study conducted demonstrated an insufficient implementation power which is influenced, amongst other things, by the size of the co-operative which represents an aggravating effect on the business as a whole. Additionally, the co-operative would more easily benefit from its high levels of goal congruence if there had been a greater homogeneity between the member associations, both in terms of size and business activity.

Research contribution: The study has contributed to an increased understanding of the Principal-agent issues that unfold in co-operative organizations, and how goal congruence is achieved in member-owned businesses. In addition, the study presents two theoretical contributions. The first one is linked to Stewardship theory, and identifies weaknesses that the theory has not been able to explain, and that these weaknesses are combated with measures more commonly found within Agency theory. The second theoretical contribution disputes previous research made on co-operatives, since we consider that internally acquired expertise should be an alternative to the externally recruited expertise.

• Public defence: 2017-09-08 10:15 Desi, A-huset, Linköping
Linköping University, Department of Management and Engineering, Fluid and Mechatronic Systems. Linköping University, Faculty of Science & Engineering.
Control Aspects of ComplexHydromechanical Transmissions: with a Focus on Displacement Control2017Licentiate thesis, comprehensive summary (Other academic)

This thesis deals with control aspects of complex hydromechanical transmissions. The overall purpose is to increase the knowledge of important aspects to consider during the development of hydromechanical transmissions to ensure transmission functionality. These include ways of evaluating control strategies in early design stages as well as dynamic properties and control aspects of displacement controllers, which are key components in these systems.

Fuel prices and environmental concerns are factors that drive research on propulsion in heavy construction machinery. Hydromechanical transmissions are strong competitors to conventional torque-converter transmissions used in this application today. They offer high efficiency and wide speed/torque conversion ranges, and may easily be converted to hybrids that allow further fuel savings through energy recuperation. One challenge with hydromechanical transmissions is that they offer many different configurations, which in turn makes it important to enable evaluation of control aspects in early design stages. In this thesis, hardware-in-the-loop simulations, which blend hardware tests and standard software-based simulations, are considered to be a suitable method. A multiple-mode transmission applied to a mid-sized construction machine is modelled and evaluated in offline simulations as well as in hardware-in-the-loopsimulations.

Hydromechanical transmissions rely on efficient variable pumps/motors with fast, accurate displacement controllers. This thesis studies the dynamic behaviour of the displacement controller in swash-plate axial-piston pumps/motors. A novel control approach in which the displacement is measured with an external sensor is proposed. Performance and limitations of the approach are tested in simulations and in experiments. The experiments showed a significantly improved performance with a controller that is slightly more advanced than a standard proportional controller. The implementation of the controller allows simple tuning and good predictability of the displacement response.

1. Simulation Aided Design and Testing of Hydromechanical Transmissions
Open this publication in new window or tab >>Simulation Aided Design and Testing of Hydromechanical Transmissions
2014 (English)In: The 9th JFPS International Symposium on Fluid Power, Matsue, 2014, 2014Conference paper, (Refereed)
##### Abstract [en]

This paper demonstrates the use of high-speed simulation in transmission conceptual design and presents a transmission test bed for hardware-in-the-loop simulations of hydromechanical transmission concepts. Complex transmissions, such as multiple-mode hydromechanical transmissions and hydraulic hybrid transmissions, present new difficulties and costs in the development process. There is today a greater demand for more efficient product development and more work has shifted towards simulation. The Hopsan simulation package allows robust, high-speed simulations suitable for both offline and hardware-in-the-loop simulation. New simulation models for hydromechanical transmissions are developed and used to simulate a known two-mode transmission concept. The same concept is also tested in hardware-in-the-loop simulations in the proposed transmission test bed. Results show good agreement with the hardware tests and highlight the proficiency of the simulation tools.

##### Keyword
Hydromechanical Transmission, Hardware-in-the-loop, Hopsan
##### National Category
Aerospace Engineering
##### Identifiers
urn:nbn:se:liu:diva-126561 (URN)4-931070-10-8 (ISBN)
##### Conference
the 9th JFPS International Symposium on Fluid Power in Matsue, Shimane Japan, on October 28-31, 2014
Available from: 2016-03-30 Created: 2016-03-30 Last updated: 2017-08-17
2. Mode Shifting in Hybrid Hydromechanical Transmissions
Open this publication in new window or tab >>Mode Shifting in Hybrid Hydromechanical Transmissions
2015 (English)In: ASME/BATH 2015 Symposium on Fluid Power and Motion Control, ASME Press, 2015, 13- p.Conference paper, (Refereed)
##### Abstract [en]

Demands for low cost sustainable solutions have increased the use of and interest in complex hydromechanical transmissions for heavy off-road vehicles. In transmissions with multiplemodes, an important condition is to maintain the tractive force during the mode shifting event. For hybrid hydromechanical transmissions, with a direct connection to a hydraulic accumulator, the impressed system pressure caused by the hydraulic accumulator has not yet been observed to interfere with this condition. In this paper, a black box model approach is used to modify the hydraulic system after obtaining knowledge regarding how it is affected by a mode shift. A comparative study is carried out where a full vehicle model of a mobile working machine is simulated with two different hydraulic systems. The results show that different system solutions imply different demands on the included components, and that the mode shifting event is not a negligible factor in heavy hydraulic hybrid vehicles.

##### Place, publisher, year, edition, pages
ASME Press, 2015
##### Keyword
Mode shifting, hydromechanical transmissions, fluid power, heavy construction machinery
##### National Category
Aerospace Engineering
##### Identifiers
urn:nbn:se:liu:diva-126556 (URN)10.1115/FPMC2015-9583 (DOI)000373970500045 ()978-0-7918-5723-6 (ISBN)
##### Conference
ASME/BATH 2015 Symposium on Fluid Power and Motion Control, Chicago, Illinois, USA, October 12–14, 2015
##### Projects
Research on Hydromechanical Transmissions and Hybrid Motion systems, RHYTHM
##### Funder
Swedish Energy Agency, P39367-1 Available from: 2016-03-30 Created: 2016-03-30 Last updated: 2017-08-17
3. Modelling of the Swash Plate Control Actuator in an Axial Piston Pump for a Hardware-In-the-Loop Simulation Test Rig
Open this publication in new window or tab >>Modelling of the Swash Plate Control Actuator in an Axial Piston Pump for a Hardware-In-the-Loop Simulation Test Rig
2017 (English)In: Proceedings of the 9th FPNI Ph.D. Symposium on Fluid Power, FPNI2016, ASME Press, 2017, UNSP V001T01A044Conference paper, (Refereed)
##### Abstract [en]

Hydraulic hybrid system solutions are promising in the quest for energy efficiency in heavy construction machines. Hardware-in-the-loop simulations, where hardware is included in software simulations in real time, may be used to facilitate the development process of these systems without the need to build expensive prototypes. In this paper, the displacement actuator of a prototype pump used in a hardware-in-the-loop simulation test rig is modelled and validated against hardware, in order to draw conclusions regarding its dynamic behaviour in a future control design. The results show that the dynamic response of the modelled displacement actuator is mainly determined by the system pressure as well as the response and geometry of the control valve.

##### Place, publisher, year, edition, pages
ASME Press, 2017
##### National Category
Mechanical Engineering
##### Identifiers
urn:nbn:se:liu:diva-133328 (URN)10.1115/FPNI2016-1570 (DOI)000398986900044 ()978-0-7918-5047-3 (ISBN)
##### Conference
The 9th FPNI Ph.D. Symposium on Fluid Power
##### Projects
Research on Hydromechanical Transmissions and Hybrid Motion systems, RHYTHM
##### Funder
Swedish Energy Agency, P39367-1
##### Note

The authors would like to thank the Swedish Energy Agency for contributing funds for the research project. Thanks also go to Bosch Rexroth for providing the prototype machines.

Available from: 2016-12-20 Created: 2016-12-20 Last updated: 2017-08-17
4. Displacement Control Strategies of an In-Line Axial-Piston Unit
Open this publication in new window or tab >>Displacement Control Strategies of an In-Line Axial-Piston Unit
2017 (English)In: The 15th Scandinavian International Conference on Fluid Power, SICFP’17 / [ed] Krus, Petter, Linköping, 2017Conference paper, (Refereed)
##### Abstract [en]

The need for efficient propulsion in heavy vehicles has led to an increased interest in hybrid solutions. Hydraulic hybrids rely on variable hydraulic pumps/motors to continuously convert between hydraulic and mechanical power. This process is carried out via the implementation of secondary control which, in turn, is dependent on a fast displacement controller response. This paper reports on a study of a prototype axial piston pump of the in-line type, in which the displacement is measured with a sensor and controlled using a software-based controller. A pole placement control approach is used, in which a simple model of the pump is used to parametrise the controller using desired resonance and damping of the closed loop controller as input. The controller’s performance is tested in simulations and hardware tests on the prototype unit. The results show that the pole placement approach combined with a lead-compensator controller architecture is flexible, easy to implement and is able to deliver a fast response with high damping. The results will in the future be used in further research on full-vehicle control of heavy hydraulic hybrids.

##### Keyword
Hydraulic hybrids, displacement control, pole placement
##### National Category
Control Engineering Other Electrical Engineering, Electronic Engineering, Information Engineering Vehicle Engineering Computer Vision and Robotics (Autonomous Systems) Embedded Systems
##### Identifiers
urn:nbn:se:liu:diva-139854 (URN)
##### Conference
The 15th Scandinavian International Conference on Fluid Power, SICFP’17, June 7-9, 2017, Linköping, Sweden
Available from: 2017-08-17 Created: 2017-08-17 Last updated: 2017-08-17Bibliographically approved
• Linköping University, Department of Computer and Information Science.
Upper body ergonomics in virtual reality: An ergonomic assessment of the arms and neck in virtual environments2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

In Virtual Reality (VR), the body is often used as input in VR, having a healthy working posture is important for long session in VR. To assess how severe different interaction methods are for the body, user tests was done in VR. 14 people participated and tested six manipulation controls which operate in different ways. Their hands' and neck's position and orientation was measured throughout the test, and from this data characteristic body postures for each control setup was chosen. These were evaluated with RULA. How great the wrist angle is can have an effect on the severity of the posture. Also whether or not the arm is to the side or across the midpoint of the body should be taken into consideration.When accounting for both the hands and neck, one of these have to come outside their comfortable zone if the hands are supposed to be seen by the user in VR.

Enskilda företagsledares påverkan på de frivilliga upplysningarna: En kvantitativ studie av svenska börsbolag2017Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis

Background

Listed companies choose to voluntary disclose a lot of information even though it could entail costs and competitive disadvantages. A likely explanatory factor for this in earlier studies has been the managements wish to signal their competence. The thought is that gifted managers wish to improve their own personal trademark and to promote their own competence via the voluntary disclosures. With these assumptions in mind, it would be fair to assume that changes in the amount of voluntary disclosures will occur when a new CEO or CFO steps in and wishes to signal competence and add theirown personal touch on the company’s external communication.

Purpose

The purpose of this study is to explain how a change of CEO or CFO will affect the corporation’s voluntary disclosures in the following fiscal year.

Method

This quantitative study was performed with a deductive approach and a cross-sectional design.

Conclusion

The study showed that a change of CFO resulted in an increased amount of voluntary disclosures by the companies. The study also found that an externally recruited CFO will disclose more than an internally recruited CFO. In addition the study also showed indications of a positive relation regarding a CEO’s share of the company and an increase of the voluntary disclosures int he next fiscal year. The same relation could not be observed to also apply for CFO’s.