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5338 Uppsatser om Electrical Power Systems - Sida 52 av 356

Optimering av OTEC-system

Ocean Thermal Energy Conversion, OTEC, is a sustainable energy conversion technology that is not yet commercialized. OTEC is a technology that utilizes the temperature difference in oceans between the warm surface water and the cold water at 1 000 m depth to run a Rankine Cycle. This technology can produce electricity and provide synergies like fresh water, air conditioning and aquaculture. A simulation program for three alternative OTEC systems has been created in order to decide which OTEC system is most profitable; closed, open or hybrid system. In this simulation a production cost analysis is performed in order to investigate and decide which one of the three systems that has the lowest production cost. The production cost analysis also analyzes if the profitability is affected by the size of the facility. After these analyzes, the most profitable of the three different OTEC-systems is expanded by an installation of solar collectors in order to see if the thermal efficiency is improved. The result shows that the most profitable system varies with the size of the facility.

Stiliga herrar : Stilanalyser av Hjalmar Söderbergs "Doktor Glas" och Bengt Ohlssons "Gregorius"

The aim of this study is to analyse the sexual power relations in contemporary urban novels of Swedish female writers.I have identified a discourse in these novels as a heteronormative matrix which power is ruled by norms and assumptions about normality in both the heterosexual and lesbian stories. For this purpose I have related to Ivar B. Neumanns theory that individuals always find a way to confront the discourse by three different strategies. These strategies are used in my study as tools to organise these novels, because it is possible to see that the protagonists find at least one of these strategy?s to her protest.The first strategy I studied was the docile.

"Det var inte mitt val" - en narrativ studie om upplevelser av elektrokonvulsiv terapi (ECT)

This study aims to highlight patients´ experiences about and thoughts of side effects fromelectroconvulsive therapy (ECT), a therapeutic method commonly used when having severedepressions. The framing of questions were how the respondents of this study describe theirlife before, during and after ECT-treatment, how the treatment has affected their daily life andhow these experiences may contribute to the awareness of power in professional relations.The study is based on three semi-structured narrative interviews and the main result showedthat, according to my interpretation, ECT as a treatment obliterated memories, quality of lifeand daily structure for all participants. Unfortunately they have all become subjects ofpsychiatric power and have faced considerable difficulty in getting professional recognitionaccording to their severe memory issues. The respondents have lost the ability to relate totheir past which clearly makes them struggle in their present context. A point in commonamong them is that neither of them wanted ECT but, because of the lack of communicationbetween them as patients and the health care in general, they all ended up getting it..

Användarorienterad design av anestesisystem

In inhalation anesthesia life-support systems are used to provide gases to the patient and to monitor important parameters. These systems are used in dynamic and stressful situations where the information-load on the operators often is significant. This thesis presents a design concept of an anesthetic system. The design goal has been to keep the information-load on the operator low with the objective to minimize confusion and error.A number of contextual inquiries were made in the operating room during surgery at four hospitals in Sweden. The goal was to understand the actual use-situations when anesthetic systems are employed.

Bolivia kvinnorörelser och multietnisk stat

This thesis examines the possibility of Bolivian indigenous women?s social movements? getting their demands of a gender equal society fulfilled in the new state which was initiated in 2005 when Evo Morales became the first president representing the indigenous people of the country. By using a qualitative method I have showed that although the Bolivian indigenous women?s social movements? historically has been significant political actors for social change in the country, with representation at both regional and national level, Bolivian women are still subordinated in the social and political sphere. By applying a feminist intersectional perspective which takes its point of departure in a understanding of power as multidimensional, where gender, ethnicity and class are constitutive principals, multiculturalism theories and a social movements theory framework, I have found that even if institutional changes, that opened the system increased the indigenous women?s social movements political participation in Bolivia, power structures based on gender limited their possibilities to influence both socially and politically.

Utredning av frekvensregleringens påverkan på mekanisk utrustning i en kaplanturbin

As a consequence of increasing wind power installations in the Nordic grid the last years, the need for regulating power has become larger. In the Nordic grid, regulating power is mainly provided by hydro power. One part of the regulating power is called frequency control, which ensures that the grid frequency is stable and close to 50 Hz.However, setting the turbine into frequency controlled operation may cause stress and wear of the components in the mechanical control system. Frequency controlling implies large and frequent servo forces and longer travelling distance of the sliding bearings in the Kaplan turbine.Based on one selected Kaplan turbine, Selsfors G1, measurements and MATLAB calculations have been performed in order to determine forces and movements of the linkage system. With these forces and movements as input, stresses and fatigue have been determined as well as sliding distances, bearing pressures and wear of bearings during a typical lifetime of 40 years.The results indicate that no severe wear exists on the bearings during 40 years of service.

Förstudie till införandet av centralt loggsystem hos Försvarsmakten

Modern IT systems tend to become more and more complex, while the number of active systems in companies increases. Furthermore, the number of security-related incidents is at an all-time high. These new conditions impose new demands on organizations. For example, it is no longer possible to manually collect and examine the systems log messages.The purpose of this thesis has been to make a comprehensive study of solutions for automated collecting and managing of log messages, analyze the Swedish Armed Forces specification for solutions for central log collection and management, and evaluating exis- ting solutions. The work consisted primarily of literature studies and evaluations of two of the Swedish Armed Forces of selected products: NetIQ Security Manager and Splunk.

Natursyn och kärnkraft / View of nature and nuclear power

Kärnkraften har så länge den funnits varit en omdebatterad energikälla. Syftet med denna uppsats är att utreda och få en bild av hur och på vilket sätt natursynen hänger ihop med åsikter om kärnkraft. Jag har redogjort för vad energi är, kärnkraftens historia i Sverige och som energikälla samt beskrivit för- och nackdelarna med kärnkraften. För att kunna ge en bild av kärnkraft och natursyn har jag genomfört kvalitativa intervjuer med personer som på olika sätt är insatta i problematiken kring kärnkraften. Min undersökning visar bland annat att natursyn är ett komplext och stort begrepp som vi bör vara medvetna om hur det fungerar i arbetet för att förbättra miljön..

Kalvens beteende i olika uppfödningssystem :

The purpose of this literature review was to investigate how the rearing systems influence the behaviour of dairy calves. Calves are social animals that form groups within the herd where play and social licking between calves are important social activities. Suckling is a complex behaviour and essential for the calf's survival. In the modern rearing systems the calf is usually separated from its mother soon after birth. Calves are then kept in individual pens, group pens or, more rarely, with a foster cow.

Investeringar i småskalig vattenkraft vid befintliga dammar : - En studie av teknik-, ekonomi- och miljöfrågor

In this thesis a method for evaluating investments in small scale hydro power is presented. An analysis of the future position that small scale hydro production will have on the Nordic electricity market is also carried out. This is done by an inventory of technology and economic and environmental aspects. The inventory is also a guide as to how the project should be implemented.Hydrolyzer is the name of the Excel tool developed to evaluate investments. The tool requests input data from the user and then evaluates the investment and generates a sensitivity analysis.

Folkbiblioteket och marknaden - En diskursanalys av ideologiska konflikter i diskussionen om marknadsanpassning av folkbibliotek

The recent decades have been characterised by a trend where the public sector's been inspired by several methods and strategies from the private sector. The public library is in this case no exception. In this context there are different perspectives on whether or not this will lead to a dramatic change of the role and values of the traditional public library. The aim of this master's thesis is to make a contribution to a deeper understanding of the ideological conflicts within the Swedish public library and its relation to the market. In the literature of library and information science I have identified two separate discourses representing two contradictory systems of meaning concerning this relation.

Bastu-frigidarium,energieffektivt system för återhämtning

Sweden is considered to have one of the world's highest animal welfare standards in agriculture. Despite this, there are shortcomings in animal husbandry. One example is overcrowding, which is a way to increase stock size without making costly investments in the buildings. It can be carried out systematically to increase profitability or due to, for example uneven calving during the year. The European Commission criticizes the fact that stocking density is not controlled under Swedish welfare inspections.

Nätverksbaserade informationssystem : Standardprotokoll ANSI Z39.50/OSI SR

This master thesis examines the development of the two earlier independent IR protocols Z39.50 and SR (Search and Retrieve, ISO 10162/10163), now Z39.50/SR, from the beginning of the 80s to 1996 and their functionality in the client/server environment.Z39.50 applications in library systems will allow easy access to information regardless of platform or location. The use of Z39.50 will create a new user environment. Almost all the library systems of the market support the Z39.50 and surprisingly the use of it in Sweden lied on a very low leve! in 1996. This thesis was followed-up by an interview and a questioner among the Swedish Z39.50 users. They could see a huge potential of development concerning the future IR process.

Värmning av avloppsvatten med spillvärme för att förbättra kvävereningen -Temperaturens inverkan på kvävereningen

The goal for this master thesis project has been to investigate the power quality in adistribution grid, which has a high fraction of dispersed power production due towindmills. The study has been done on a grid in Laholm South of Halmstad, whereapproximately 45 windmills are connected to the distribution grid owned by SHKEnergi. The investigation has been focused on to two radialy fed 20 kV lines, wheretwelve windmills are connected.Voltage variations have been studied by creating a model of the grid in the simulationprogram SIMPOW. The largest deviation that has been found in any point of the gridis ±1.9 % of the nominal voltage. This deviation is a result of varying powergeneration from the windmills and the voltage regulation at the connection point ofthe line.

Från föreställningar till relevanta system - Linköpings universitetsbibliotek analyseras med hjälp av Soft Systems Methodology

The background to this thesis is the impact of information technology on libraries and librarywork. If information technology causes changes in the tasks and work of libraries, thenlibrary organisations should also change. It is important to engage and inform the staff if suchchanges are to succeed. This thesis investigates the notions about library tasks and librarywork among eight "middle-managers" at Linkopings universitetsbibliotek.The investigation is based on interviews and then analysed with Soft Systems Methodology(SSM). By identifying the "Weltanschauung" of the staff, the thesis tries to create logicallydesirable and culturally feasible models of systems relevant to the situation at Linkopingsuniversitetsbibliotek.

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