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10977 Uppsatser om Power system simulation - Sida 50 av 732
Beslutstödssystem for investeringar och underhåll i eldistributionssystem
I detta examensarbete har en tillförlitlighetsmetod tagits fram som väger samman kostnadspåverkande faktorer för investeringar och underhåll i eldistributionssystem med kostnader förknippade med avbrott. Syftet med metoden är att möjliggöra för nätplanerare och projektörer att jämföra olika investeringsalternativ för att kunna kostnadseffektivisera investeringarna i eldistributionssystem. Med tillförlitlighetsanalys kan den förväntade avbrottstiden i systemets uttagspunkter beräknas. Kopplas en kostnad till den förväntade avbrottstiden i uttagspunkterna kan den förväntade avbrottskostnaden för distributionssystemet beräknas. Syftet med simuleringarna har varit att undersöka om det går att minimera den totala kostnaden, investeringskostnader samt förväntade avbrottskostnad, genom slumpvisa investeringar i systemets ledningssektioner. Simuleringarna har genomförts på ett fiktivt mindre system.
Framtagning av förbättringsförslag för SNCR-system
The gas turbines in the Swedish secondary reserve are reaching the end of their technical lifetime, hence alternative solutions need to be considered. One of the solutions thought to have the greatest potential is the use of so called consumptionreduction. By entering contracts with large consumers, agreements are made to reduce consumption in the event of major disturbances in the power system and thus being used as a secondary reserve. This thesis investigates the feasibility of consumption reduction as part of the secondary reserve. This has been achieved by developing a requirement specification for the disturbance reserve and by studying the technical and economic potential for consumption reduction among a range of consumers.The technical potential for consumption reduction that fulfils the requirements for participating in the secondary reserve are on average 750 MW in SE 3 and 98 MW in SE 4.
Är användbarheten i säkerhetskritiska system eftersatt?
I denna rapport har vi undersökt hur utvecklarna tagit hänsyn till användbarheten för slutanvändarna vid utvecklingen av ett säkerhetskritiskt system. Resultatet erhölls genom en empirisk fallstudie på två företag som utvecklar säkerhetskritiska system. Datainsamlingen bestod av intervjuer med personer som varit delaktiga i och har kunskap om utvecklingen av systemen som ingick i vår fallstudie. Sedan analyserades insamlad data mot teori inom Människa ? Dator ? Interaktion (MDI) samt teori om säkerhetskritiska system.
Metoder för trust : Hur praktiker arbetar för att bygga förtroende till knowledge management-system
This thesis examines how knowledge management professionals use trust as a component in the creation of knowledge management systems, and what methods they use for building trust.Adopting a grounded theory approach, interviews with 8 knowledge management professionals active in different industries served as the base for an analysis that identified trust to be the single most important common factor in the data. The concept of trust used by the informants was identified as relating to the knowledge management system itself, rather than other users, employees or groups in an organisation.Building trust, the KM-professionals mainly focused on three methods: simple solutions, system superiority, and implementation security. Using these methods, the KM-professionals seek to ensure system trust by creating opportunities for users to obtain positive experiences of using the system, and thereby generate a foundation for a trust-based relationship between the user and the system..
Värdering och jämförelse av kvalitetsfaktorer för lokal kollektivtrafik i Helsingfors och Göteborg
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.
Vindkraft och rennäring
The Swedish Parliament has decided to increase the share of electricity produced by wind power. The same parliament has decided that the Sami have the right to herd reindeer over 50% of the country's land area. In this literature review the potential impact wind power development and associated infrastructure may have on reindeer husbandry conditions are examined.
The unique physiology of the reindeer enables it to live out of grazing in the arctic climate in the north of Sweden. For reindeer husbandry to be long-term productive and sustainable, it is important that there is enough land for grazing. The research available on how reindeer are disturbed by human activities such as roads, mines, hikers, etc., clearly indicates that the reindeer avoids areas close to such disturbance.
Har dagens ungdom koll på folkmusiken? : en jämförande studie mellan två åttondeklasser
AbstractThe future of ethanol is depending on good solutions for the production. ENA energy power plant produces electrical power and district heating by heating biofuel. By building an integrated bioenergy plant surplus steam could be used to produce ethanol as fuel to vehicle.This would mean that ethanol is produced renewable energy and the energy for the process derives from the surplus of power. ENA energy, MDH (the University of Mälardalen) and the energy authority has initiated a research project were different bioenergy combinations integrate with existing power plant. As a part of the project which size an integrated factory should be to gain the best efficiency for the plant was investigated. Consideration will be taken to the cost of the production in order to be competitive to the price of imported ethanol. Etanolens framtid vilar på bra lösningar för framställning. I ENA energi kraftverk i Enköping produceras el och fjärrvärme genom eldning av biobränsle. Genom att bygga ett integrerat bioenergikraftverk där skulle man kunna använda överskottsånga till att framställa etanol som fordonsbränsle.
Fiolmetodiken hos Leopold Mozart och Paul Rolland
AbstractThe future of ethanol is depending on good solutions for the production. ENA energy power plant produces electrical power and district heating by heating biofuel. By building an integrated bioenergy plant surplus steam could be used to produce ethanol as fuel to vehicle.This would mean that ethanol is produced renewable energy and the energy for the process derives from the surplus of power. ENA energy, MDH (the University of Mälardalen) and the energy authority has initiated a research project were different bioenergy combinations integrate with existing power plant. As a part of the project which size an integrated factory should be to gain the best efficiency for the plant was investigated. Consideration will be taken to the cost of the production in order to be competitive to the price of imported ethanol. Etanolens framtid vilar på bra lösningar för framställning. I ENA energi kraftverk i Enköping produceras el och fjärrvärme genom eldning av biobränsle. Genom att bygga ett integrerat bioenergikraftverk där skulle man kunna använda överskottsånga till att framställa etanol som fordonsbränsle.
Value at Risk : En jämförelse mellan VaR-metoder
Bakgrund: I och med att Basel II har instiftats i Sverige så måste finansiella institutioner beräkna sin marknadsrisk på sina portföljer. Detta kan göras genom olika VaR metoder. Dessa ger dock olika uppskattningar på marknadsrisken. De finansiella instituten får använda sig av den metod som de anser reflektera marknadsrisken bäst. Det finns dock ingen metod som utsetts till standard.Syfte: Syftet med detta arbete är att jämföra olika VaR-metoders skattning av marknadsrisken utifrån verkligt utfall, för att urskilja vilken metod som är funktionsdugligast.Avgränsningar: Denna undersökning inkluderar fyra olika VaR metoder.
Hemautomation : Spara energi genom att automatisera hemmet
In today's society there is a significant focus on energy efficiency. Despite this, people leave lamps, televisions and computer screens etc. powered on unnecessarily. The goal of this project is to build a simple prototype for home automation where a user, via an application on a mobile phone, can switch on and off the power of an electrical products in the home and as well as being able to check whether such products are switched on or off. The prototype will also collect data on power consumption for these electrical products.
Att leda som man lär : Införandet av en ledarfilosofi i en professionell organisation
Since a lot of the power in a professional bureaucracy lays within the operative profession with its strong corporate culture and strong co-workers the executive occupy a weak position. Their power comes from the complexity of the operative professionals work and the difficulties to supervise that work. To avoid conflicts it?s important to make all expectations on the executive equivalent. This can be done by defining the roles of the executives in a philosophy.
Och kvinna : en kritisk analys av den mediala diskursen kring kvinnliga politiker
The aim of this paper is to describe, visualise- and analyse media’s discursive representations of female politicians in Swedish printed media. The focus of the analysis is to show if, and how these images can be understood and interpreted in terms of a socially constructed gender stereotyped suborder. The paper takes it's theoretical and methodological departure in the discourse analysis, which is combined with feminist political theory. Feminist political theory is concretised in the use of what Yvonne Hirdman calls the "gender system" which arranges the sexes into their respective genders and is based upon two rules/principles/logics: 1) the rule of distinctive separation, and 2) the male norm. Closely related to the aim of the paper lies also the critical theoretic assumption that people has to be aware of their own part in the production and reproduction of the discourse in order to change make a change.
Realtidsbaserat kollaborativt editeringssystem med stubbaserad versionshantering : Implementation av versionshantering inom ett realtidsbaserat kollaborativt system
Denna rapport tar upp problem med revisionskontroll i realtidsbaserade kollaborativa system. Enligt Fan & Sun (2012a); Fan & Sun (2012b) behöver man bryta kraven som definerar realtidsbaserade system för att uppnå detta.Den stubbaserade lösningen som beskrivs i rapporten lyckas minska antalet fel i testfallen som utförts i fallstudierna. Genom att implementera personliga editeringsflikar och stubbar är det möjligt att ha revisisionskontroll i ett realtidsbaserat system. Dock för att detta ska vara effektivt och användbart bör detta endast användas i specifika fall och med noggrann granskning.Fallstudien som genomförts visar inte på några imponerande siffror men en förbättring är fortfarande möjlig vid specifika fall..
Instrumentvården i grundskolan. Intervjuer med fyra behöriga musiklärare
AbstractThe future of ethanol is depending on good solutions for the production. ENA energy power plant produces electrical power and district heating by heating biofuel. By building an integrated bioenergy plant surplus steam could be used to produce ethanol as fuel to vehicle.This would mean that ethanol is produced renewable energy and the energy for the process derives from the surplus of power. ENA energy, MDH (the University of Mälardalen) and the energy authority has initiated a research project were different bioenergy combinations integrate with existing power plant. As a part of the project which size an integrated factory should be to gain the best efficiency for the plant was investigated. Consideration will be taken to the cost of the production in order to be competitive to the price of imported ethanol. Etanolens framtid vilar på bra lösningar för framställning. I ENA energi kraftverk i Enköping produceras el och fjärrvärme genom eldning av biobränsle. Genom att bygga ett integrerat bioenergikraftverk där skulle man kunna använda överskottsånga till att framställa etanol som fordonsbränsle.
Solenergi på Nya Karolinska Solna
In today?s society climate change has grown to one of the largest global issues. To reduce emissions of greenhouse gases, large changes of the energy system are required. An increasingly popular solution is investments in local production of renewable energy resources like wind, solar or geothermal power. The following report examines the possibility for implementing a solar power plant on the new hospital Nya Karolinska Solna. Two different technologies for extraction of solar energy has been studied, solar thermal collectors to meet the need of heating and solar cells to satisfy the need for electricity linked to operating the hospital building.