With an expanding access of decision supporting technologies and a growing demand for lowered carbon dioxide emissions, sustainable development with the help of modern interfaces has become a subject for discussion. There are different opinions on how to motivate users to live more pro-environmentally and to lower their carbon dioxide emissions with modern technology. This paper analyses the use of chatbots as a mean to motivate people to live more sustainable lives.  To evaluate the field, a literature study was conducted covering eco-feedback technology, recommender systems, conversational user interfaces, and motivation for pro-environmental behavior. The effect of motivational factors from behavioral psychology were tested, and their impact on peoples food consumption habits. The findings of this paper were based on three chatbot prototypes; one that is built on the motivational factor of information, a second one that is implemented on the motivational factor of goal-setting, and a third one that follows the motivational factor of comparison. Twenty-seven persons participated in the study, seven people at the early stages of the project, and twenty people that used the chatbots. The user experience of the chatbots was evaluated, resulting in guidelines on how to design for chatbot interfaces and behavior change. The result from the user interviews indicates that chatbots can affect and motivate people to consume food in a more sustainable way.

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We study the genealogical structure of samples from a population for which any givengeneration is made up of direct descendants from one randomly chosen previousgeneration. These occur in nature when there are seed banks or egg banks allowingan individual to leave offspring several generations in the future. Kaj et al. studied in2001 the case where any given generation is made up of descendants from severalprevious generations and showed how this temporal structure in the reproductionmechanism causes a decrease in the coalescence rate. In this project we will showthat having all samples pick their parents in one randomly chosen generation will leadto a coalescent process which is equivalent to a time shifted version of Kingman’scoalescent, time shifted with the age distribution of the seed bank.

As the largest global renewable source, hydropower shoulders a large portion of the regulation duty in many power systems. New challenges are emerging from variable renewable energy (VRE) sources, the increasing scale and complexity of hydropower plants (HPPs) and power grid. Stable and efficient operation of HPPs and their interaction with power systems is of great importance. Theoretical analysis, numerical simulation and on-site measurement are adopted as main study methods in this thesis. Various numerical models of HPPs are established, with different degrees of complexity for different purposes. The majority of the analysis and results are based on eight HPPs in Sweden and China. Stable operation (frequency stability and rotor angle stability) and efficient operation are two important goals. Regarding the stable operation, various operating conditions are analysed; the response time of primary frequency control (PFC) and the system stability of isolated operation are investigated. A fundamental study on hydraulic-mechanical-electrical coupling mechanisms for small signal stability of HPPs is conducted. A methodology is proposed to quantify the contribution to the damping of low frequency oscillations from hydraulic turbines. The oscillations, with periods ranging from less than one up to hundreds of seconds, are analysed. Regarding the efficient operation, a description and an initial analysis of wear and tear of turbines are presented; a controller filter is proposed as a solution for wear reduction of turbines and maintaining the frequency quality of power systems; then the study is further extended by proposing a framework that combines technical plant operation with economic indicators, to obtain relative values of regulation burden and performance of PFC. The results show that the coupling between the hydraulic-mechanical subsystem and the electrical subsystem can be considerable and should be considered with higher attention. Effectiveness and applicability of different numerical models are shown, supplying suggestions for further model optimization. For the influence from power systems on HPPs, the dynamic processes and corresponding control strategies of HPPs under diverse disturbances and requirements from power systems are addressed. For the influence from HPPs on power systems, quantifications of frequency quality and the hydraulic damping are conducted utilising proposed methodologies.

This thesis project is a theoretical and practical study on recommender systems (RSs). It aims to help the planning of course selection for students from the Master Programme in Computer Science in Uppsala University. To achieve the goal, the project implements a recommender service, which generates course selection recommendations based on these three factors:     (i) student users’ preferences     (ii)  course requirements from the university     (iii) best practices from senior students The implementation of the recommender service takes these three approaches:      applying frequent-pattern mining techniques on senior students’ course selection data ,  performing semantic queries on a simple knowledge organization system (SKOS) taxonomy file that classifies computing disciplines, applying constraint programming (CP) techniques for problem modelling and resolving when generating final course selection recommendations     The recommender service is implemented as a representational state transfer (REST) compliant web service, i.e., a RESTful web service. The result shows that aforementioned factors have positive impact on the output of the service. Preliminary user feedback gives encouraging rating on the quality of the recommendations.     This report will talk about recommender systems, the semantic web, constraint programming and the implementation details of the recommender service. It focuses on in-depth discussion of recommender systems and the recommender service’s implementation.

Med en problemformulering, "Vad fångar elevernas intresse på tekniklektionerna och går det att använda till planering av undervisningen?", gör detta examensarbete ett försök att skapa en grund för att kartlägga elevernas intresse i teknikämnet på högstadiet. Detta gjordes genom en enkätundersökning, där elever tillfrågades om deras intresse i ämnet teknik. Informationen är tänkt att bidra till att, som tekniklärare, kunna ha lektioner som följer läroplanen och samtidigt försöka uppfylla elevernas generella intressen. Enkätfrågorna tar upp intressen för såväl arbetssätt som ämnesinnehåll för att kunna ringa in vad eleverna tycker skapar intressant undervisning i ämnet. Resultaten pekar på att eleverna intresserar sig för innehåll som är relevant för dem, t.ex. mobiltelefoner, samt att de gärna vill arbeta praktiskt. Då läroplanen för ämnet teknik är ganska öppen för tolkning, finns det stora möjligheter att lägga upp undervisningen att till stor del ta till vara på dessa intressen.

Elever kommer idag till gymnasieskolan med varierande bakgrundskunskaper, dessa kunskaper inom ett område borde vara något som eleverna kan dra nytta av inom olika kurser. Mitt syfte med den här uppsatsen var att dels försöka se om förkunskaperna gav någon fördel på ett slutprov inom ett moment, men också att se hur stor den faktiska kunskapsökningen kunde bli för en grupp elever. Detta åstadkoms genom att skapa ett prov som eleverna i årskurs 1 på Teknikprogrammet fick göra innan ett givet moment i kursen Teknik 1 påbörjades. De gjorde sedan om samma prov igen i slutet av momentet som ett slutprov. Därefter analyserades resultaten från de båda proven och jämfördes med varandra. Undersökningen visade på en procentuell kunskapsökning, det vill säga en differens mellan slutprov och förkunskapsprov, på ca:43 % efter ca: 3 veckors studier. Däremot gick det inte att utläsa huruvida en elev med goda förkunskaper hade ett bättre eller sämre slutresultat jämfört med elever med sämre förkunskaper.

Denna rapport kommer att visa på hur utvecklingen av en prototyp för lagring av fysiska rörelser har gått till. Vilka komponenter som har valts och varför. Arbetet är utfört på uppdrag av Medicinsk Teknik – Forskning och Utveckling (MT-FoU) vid Umeå Universitet i Sverige. MT-FoU har även bistått med mjukvara och möjligheten till 3D-utskrift av behållare för prototypen. Prototypen kan lagra information om rörelser med hjälp av accelerometer, gyroskop och magnetometer. Informationen lagras på ett SD-kort och överförs sedan trådlöst via en nätverksrouter till klientsidan medhjälp av WiFi. Fysisk aktivitet har visat sig vara en viktigare del av människans hälsa än tidigare trott. Därför är det alltid viktigt att röra på sig mycket men och på rätt sätt. Med hjälp av denna produkt kan information om hur du exempelvis rör dig under ett träningspass registreras och analyseras. I denna rapport tas tillförlitligheten upp hos produkten med hjälp av två andra kommersiella produkter som data jämförs mot. / This report will show how the development of a prototype for the storage of physical movements has been developed. Which components that have been chosen and why. The work is performed on behalf of the Biomedical Engineering - Research and Development (MT-FoU) at Umeå University, Sweden. MT-FoU has also assisted with the software and the possibility of 3D printing of containers for the prototype. The prototype can store information about movement using the accelerometer, gyroscope and magnetometer. The information is stored on an SD card and then transmitted wirelessly via a network router to the clientside using WiFi. Physical activity has been shown to be a more important part of human health than previously thought. It´s always important to move much but it´s also important that we move in a right way as well. With the help of this product information on moves during a training session is recorded and analyzed. In this report, the reliability of the product is measured with the help of two other commercial products which data is compared against.

The genesis of atherosclerosis has previously been shown to be affected by the frictional load from the blood on the vessel wall, called the wall shear stress (WSS). Assessment of WSS can therefore provide important information for diagnoses, intervention planning, and follow‐up. Calculation of WSS requires high‐resolved velocity data from the vessel, which in turn can be obtained using computational fluid dynamics (CFD). In this work large eddy simulation LES was successfully used to simulate transitional flow in idealized as well as subject specific vessel models. It was shown that a scale resolving technique is to prefer for this application, since much valuable information otherwise is lost. Besides, Reynolds‐Averaged Navier‐Stokes (RANS) models have generally failed to predict this type of flow. Non‐pulsating flows of Reynolds numbers up to 2 000 in a circular constricted pipe showed that turbulence is likely to occur in the post‐stenotic region, which resulted in a complex WSS pattern characterized by large spatial as well temporal fluctuations in all directions along the wall. Time averaged streamwise WSS was relatively high, while time averaged circumferential WSS was low, meaning that endothelial cells in that region would be exposed to oscillations in a stretched state in the streamwise direction and in a relaxed state in the circumferential direction. Since every vessel is unique, so is also its WSS pattern. Hence the CFD simulations must be done in subject specific vessel models. Such can be created from anatomical information acquired with magnetic resonance imaging (MRI). MRI can also be used to obtain velocity boundary conditions for the simulation. This technique was used to investigate pulsating flow in a subject specific normal human aorta. It was shown that even the flow in healthy vessels can be very disturbed and turbulence like, and even for this case large WSS variations were seen. It was also shown that regions around branches from the aorta, known to be susceptible for atherosclerosis, were characterized by high time averaged WSS and high oscillatory shear index. Finally, the predictive capability of CFD was investigated. An idealized model of a human aorta with a coarctation and post‐stenotic dilatation was studied before and after a possible repair of the constriction. The results suggested that small remaining abnormalities in the geometry may deteriorate the chances for a successful treatment. Also, high values of shear rate and Reynolds stresses were found in the dilatation after the constriction, which previous works have shown means increased risk for thrombus formation and hemolysis.

Under en lång tid har det satsats på att energieffektivisera byggnader under dess driftfas, då tidigare studier visar att driftfasen står för 85 procent av en byggnads totala energianvändning på 50 till 100 år, medan produktionsfasen står för 15 procent. Att bara ta hänsyn till klimatbelastning som uppstår under byggnadens bruk, har som konsekvens att energiförbrukningen förskjutits i fas, vilket resulterar i att energifördelningen har förflyttats till en ökad andel i produktionsfasen. Detta examensarbete syftar till att lyfta frågan om byggproduktionens energianvändning, genom att kartlägga hur mycket energi som förbrukas på plats i produktionskedet för att bygga ett flerbostadshus beläget i Umeå.  I detta examensarbete har tre olika stommaterial, platsgjuten betong, stål med prefabricerade betong och trä, undersökts och analyserats. För att projektet ska kunna genomföras har det utgåtts från ett referensobjekt, Kvarteret Sjörået på Tomtebo i Umeå som innefattar tre byggnader om fyra plan vardera, där endast ett fack av ett av husen undersöktes. Studien utgår från att fastställa det energikrävande momentet för de olika stommaterialen, för att sedan beräkna energiförbrukningen för dessa stommaterial baserat på det energikrävande momentet. Under projektets gång har olika aktörer inom byggbranschen kontaktats, simuleringar utförts i programmet TorkaS och en mängd olika antagande gjorts. Gällande mängder material har överförts från rapporten Livscykelanalys med fokus på energianvändning under tillverkningsfasen – en jämförelse mellan olika stommaterial av Mi Von Ahn. Resultatet som fås för det studerade referensobjektet visar att skillnaden i energianvändning för de olika stommaterialen är stor under produktionsfasen för referensobjektet. Resultatet visar att det går mest energi åt för att torka platsgjutna betongelement, då det krävs fläktar som i stort sätt drar mycket energi. När det är frågan om prefabricerade stomelement spelar stomelementens vikt stor roll, då det behövs lyftkranar som är anpassade efter byggelementens tyngd. Dessutom drar lyftkranarna olika mycket el, beroende på elementens vikt och lyfthastighet. Trästommen var mest fördelaktig i denna studie, på grund av stommens lätta vikt. Viktigt att poängtera är att resultatet för denna studie utgår från ett specifikt referensobjekt, vilket innebär att resultatet kan se annorlunda ut beroende på bland annat val av systemgränser. / For a long time the focus of energy efficiency in building constructions has mainly been focused on its operational phase, as previous studies show that the operational phase accounts for 85 percent of a building’s total energy consumption during its lifetime, estimated at 50 to 100 years, the production phase is estimated to account for 15 percent. By only accounting for the climate impact from buildings during the operational phase, has led to energy consumption shifting in phase, resulting in an increased share of the total energy distribution in the production phase. This thesis aims to highlight the issue of the energy consumption during the construction phase, by mapping how much energy is consumed on the spot in the production stage to build an apartment building located in Umeå. In this thesis three different framing materials has been examined and analyzed; in situ concrete, steel combined with precast concrete and wood. In order to implement the project, the main focus has been on a reference object, Kvarteret Sjörået in Tomtebo in Umeå, which includes three buildings of four floors each, where only one compartment of one of the buildings has been examined. The study of this thesis begins with determining the energy-consuming steps for each framing materials, followed by calculating the energy consumption of these frame materials. During the project contacts have been taken with various stakeholders from the construction industry in addition to simulations performed in the program TorkaS and a variety of adoption has been made. Regarding the amounts of material assumed consumption in this study a basis has been taken in the previous thesis Life cycle analysis with a focus on energy use during the manufacturing phase – a comparison of frame materials by Mi Von Ahn.  The result obtained for the reference object shows that the difference in energy consumption between the studied frame materials is high during the production phase of the reference object. The result further shows that in situ concrete frame is the most energy consuming alternative during the construction phase due to need of large fans that is consuming a lot of energy. When it comes to prefabricated frame materials the energy consumption is largely due to the need for cranes where one important aspect is the weight of the elements. In addition cranes use electricity depending on the elements weight and depending on the lifting speed. Wood was most advantageous in this study, because of its light weight body. Important to note is that the results of this study are based on a specific reference object, which means that the results may be different depending on many factors, for example the choice of system limits.