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This master thesis project has been performed in cooperation with TAC, a building automation company in Malmö and the Department of Automatic Control at LTH. TAC has experienced problems for some time with their PID controllers. This master thesis has therefore investigated the use of PID control at TAC, the problems with the existing controllers. The thesis also describes a new PID controller tha

Clarifying the mechanisms maintaining atrial activity during atrial fibrillation (AF), still remains as a relevant topic. The purpose of this master thesis is to apply correlation analysis and system identification methods to study spatial and temporal propagation of atrial activation along coronary sinus (situated in the posterior left part of the heart, in the groove between left atrium and left

This rapport investigates the transmitter of the Ericsson Bluetooth radio. The open loop modulation scheme of the existing design is theoretically very simple but difficult to implement with available components. Frequency drift of the carrier is a common result of open loop modulation. This work therefore investigates an idea of frequency regulation where the regulation is active during modulatio

The report describes the development of a global model of a simple gas turbine in order to simulate the dynamic behaviour. The Modelica language is used for the creation of the model. The model is based on the evaporative gas turbine located in the Department of Heat and Power Engineering in Lund. This turbine was run as a conventional turbine before including the heat exchange and the evaporative

This project considers a special class of aero-dynamics of two different underactuated systems. The two systems under consideration are the Pendubot (actuator at the hip) and the Acrobot (actuator at the knee). The main objectives are to show stability and periodicity of the two systems. The next step is to change the zero-dynamics such that resulting periodic orbits produce walking gait patterns.

This thesis in Anthropology researches the identity of Macedonians in the wake of a controversial name change to solve a long standing dispute with Greece. The dispute is based on rivalring historical narratives and the legacy of antique king and conqueror Alexander the Great of ancient Macedon, a region currently shared by Greece and the newly renamed republic of North Macedonia, who both claim d

Problemområde: Hållbar turism har ett tydligt fokus på den miljömässiga hållbarheten, vilket har bidragit till att den sociala hållbarheten har blivit bortprioriterad. Det finns olika tolkningar av social hållbarhet vilket medför svårigheter för aktörers engagemang inom besöksnäringen. Detta tyder på att en större förståelse för social hållbarhet behövs. Syfte: Vårt syfte handlar om att bidra til

To find approximate solutions to initial value problems (IVPs) one can use a wide range of numerical methods. A special group of IVPs referred to as stiff, can be numerically solved by a chain of methods, beginning with an implicit method then Newton's method and last, General minimal residual (GMRES). For GMRES to be more time-efficient, we need to apply a preconditioner to the system of equa

The need for sustainable solutions to the negative state of the Earth is urgent. Ethical choices need to be made and humanity’s endowed imagination needs to be employed to find creative ways ahead. Literature has a potential to open minds and challenge perceptions, which is necessary to activate the creative imagination needed to find visionary solutions. This analytical research paper explores ho

This is a study of uncertainty in the corporate setting from the perspective of individual employees. While some interviewees talk about accepting uncertainty as an unavoidable state, others tell stories of dread and anguish, associated with instability in the work environment. This research shows how uncertainty as a stress inducing factor can affect both productivity and employee wellbeing, by r

Ett uråldrigt hus med murkna tegelstenar som är täckta med mossa träder fram ur mörkret. Murgrönan sträcker sig över fasaden och döljer de tomma fönstren. Ett litet torn med spetsiga spiror höjer sig över taket och bryter byggnadens redan bristande proportioner. Ett stenvalv inramar en massiv träport med excentriska inristningar och förskräckliga maskaroner. Dörrens groteska portklappar är orörda.The aim of this thesis is to analyse the motif of the haunted house in Aurora Ljungstedt’s Hin Ondes hus (1853) and Mats Strandberg’s Hemmet (2017). In order to compare the motif in these two Swedish novels, Edgar Allan Poe’s short horror story “The Fall of the House of Usher” (1839), which works as a frame for my comparative study. In this thesis, I try to analyse and interpret and Hin Ondes hus

Behövs kemiska bekämpningsmedel inom jordbruket? I Sverige finns ekologiska jordbruk, detta betyder bland annat att kemiska bekämpningsmedel inte används för att bespruta grödorna inom dessa jordbruk. Ekologiska lantbrukare använder sig istället av biologisk kontroll, vilket betyder att naturliga rovdjur till skadeinsekter introduceras i jordbrukslandskapet för att äta skadeinsekterna. För att unChemical pesticides have long been used to keep crops free from pests, but in modern agriculture biological control is viewed as a viable alternative to pesticides. The concept of biological control is to implement predators that feed upon the pests. It can however be difficult to follow the effects of the biological control in the field, which is why a theoretical mathematical model has been desi

The dogged black nose in dogs The different sensory systems of animals is a well-studied subject. Today it is virtually common knowledge that birds of prey have good sight, that bats use echolocation and that dogs have a good sense of smell. However, recent studies show that there is more to the noses of our precious dogs, then we for a long time knew. Apart from participating in the olfactory sy

This paper examines the impact of foreign direct investment (FDI) in the industrial upgrading process of Vietnam based on the concept of the new structural economics. The most recent development of industries in Vietnam is analysed using the annual data published by the statistical office of Vietnam and the studies done by various academics on spillovers effects of FDI. The paper finds the an impo

Utvärdering av en sändarspole med 8 oberoende kanaler på ett MR-system med hög fältstyrka Magnetresonanstomografi med höga magnetfältsstyrkor har potential att skapa bilder med otrolig kontrast. För att kunna uppnå detta över hela hjärnan måste det ojämna utsända RF-fältet jämnas ut. Oberoende sändarelement tillhandahåller lösningen!Ultra high magnetic field (UHF) MR-systemsis an interesting research area, the systems offer images with higher spatial resolution than its lower field counterpart. One of the disadvantages with UHF MR is that they lead to a worsened B1-field homogenity, a homogentity essential for the creation of MR-images. In the project an 8 independent channel transmit system is charachterised. The transmit sy

Många groddjur har minskande populationstrender både lokalt och globalt. Inventeringar av groddjur är en viktig del av arbetet för att få mer information om deras utbredning för att kunna skydda groddjuren och deras miljöer. Detta kan ha positiva effekter även på andra djur och växter eftersom groddjur är bra indikatorer på rika miljöer. Genom sitt vattenupptag via huden är groddjuren extremt käns

Idag är var tionde art i Sveriges skogar hotad. På Sveriges skogsägare vilar således ett stort ansvar för att bevara landets biologiska mångfald. Svenska Kyrkan har som Sveriges femte största skogsägare och på grund av sina värderingar möjlighet att göra stora insatser i arbetet för att bevara Sveriges skogsarter. I min studie har jag sett att Svenska Kyrkans arbete för att bevara biologisk mångfa

Den okända Arnöbäcken – Vad finns i den? Eutrofiering, vilket är övergödning, är ett stort problem både i färskvatten och utmed hav i regionala områden såsom i Östersjön. I Östersjön är den största bidragsgivaren till eutrofiering det massiva utflödet av mineraler och näringsämnen från floder och bäckar. Strax intill Nyköping ligger Strandstuviken som är en bukt i Östersjön. Länsstyrelsen i SöderEutrophication is a serious problem that is affecting the Baltic Sea and its streams connecting to it. It brings a negative impact on the biodiversity, the streams recreational value, sport fishing and also the overall ground water quality. Recently, there have been many restoration attempts on streams across Sweden, to try to repair the streams and prevent them from leaking nutrients and minerals

The migration politics in Sweden have changed drastically within the past years as it has introduced stricter asylum policies and higher securitisation of borders. As a result, an increased number of people are forced to live as undocumented migrants, meaning without a legal permit to stay in the country. This thesis aims to contribute to the analysis of this development by investigating the role