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10939 Uppsatser om Tekniska system - Sida 61 av 730
Axle Link - en kortslutningsskyddad säker DC-överföring
Denna examensrapport redogör för hur man kan få en kortslutningsskyddadoch säker inkoppling av en DC-länk mellan två skiljda elektriska system.Rapporten bygger på hur en lastbil ska kunna få en större säkerhet för attbibehålla sina elektriska bromsar om tex ett av bromssystemen tappar sinordinarie matning.Lastbilens bromssystem består idag av två skiljda elektriska system med ett 24volts strömförsörjande batteri vardera. Det ingår två stycken elektriskabromsar i varje system. Om det tex blir fel på en av bromsarna och dennapåverkar ett av systemen vill man kunna koppla bort denna enskilda bromsmed sitt system. Man vill även kunna försörja den fungerande bromsen somsitter i samma system via en så kallad Axle Link. Denna strömmatningslänksitter mellan två hjulpar på samma axel.I denna studie undersöktes möjligheten att realisera en kortslutningsskyddadoch säker DC-överföring via en Axle Link, i första hand med diskretakomponenter.
Hälso- och sjukvården i Region Skåne är patientprocessorienterad
Syftet med examensarbetet är att utreda vilken potential det finns för en samverkan mellan Tekniska Verken och växthus. Målet är att genom industriell symbios skapa en resurseffektiv systemlösning där Tekniska Verkens produktionsanläggningars miljöprestanda förbättras samtidigt som växthusets klimatpåverkan minskas.Tekniska Verken har överskottsvärme i sina produktionsanläggningar. Under 2007 hade Gärstad- och Kraftvärmeverket 54 GWh överskottsvärme. Största delen av överskottsvärmen fanns på sommaren, då värmebehovet i fjärrvärmesystemet var som lägst. Effekten som kyldes bort under sommaren uppgick till 25 MW.Om ett par år kommer Svensk Biogas anläggning i Linköping ha överskottsvärme på 26 GWh per år.
Digitalisera loggboken : En analys av utmaningarna med att utveckla IT-stöd för kunskapsintensiva verksamheter
Failed system development projects are a common sight within the IT-industry. During the last ten years we have seen several more or less disastrous high profile projects being reported in the news. One aspect that might hold some of the responsibility for these failures is the fact that more organisations are knowledge intensive which makes their work processes difficult to capture in computer systems. How requirements engineering is handled becomes even more important in these cases, where processes are unpredictable and rely on individual judgement and knowledge. In this study we have examined the challenges of developing systems for knowledge intensive businesses through a method of qualitative case study of a university laboratory.
Skyltkoncept på Stenby Återvinningscentral : med färg, bild och form
Texten jämför det analoga- och digitalafotografiet. Disskutioner kring arbetssättet, uttrycket i fotografiet, uppfattningen av det, de olika tekniska asspekterna och känslan i fotografiet är områden som berörs i texten. Även kamerans och fotografiets historia i allmänhet tas upp..
Bremsningens effekter hos häst : utvärderat med hjälp av termografi, hormonanalyser och hematologi
Twitching is frequently used in horse management because of its sedating and pain-relieving effects. In this study, the effects on the horse?s nervous system by twitching were investigated by thermography of the skin temperature. The temperature is regulated by the sympathetic nervous system through postganglionic sfincters at the capillaries of the skin. The effects on the endocrine activity have also been studied by the measuring of ACTH and cortisol in blood plasma.
Prefabricerade passivhusväggar
Background: The most energy efficient houses today are so called passive houses. These houses achieve high energy-efficiency partly by having well insulated walls. U-value describes the amount of heat transfered through a building element, the more insulation, the smaller U-value. A typical passive house wall have a U-value of 0.10 W/m2,°C. The passive houses are primarily made as small family houses and not as a block of apartments.
Dimensionering och konstruktion av Villa X
AbstractIn the fall of 2003 a project was started in the Swedish building sector that is called BASTA (the building sectors’ termination of especially harmful substances). The project is operated by the building companies NCC, Skanska, PEAB and JM, the Swedish Building Industry and the Swedish Environmental Institute IVL. The purpose of the project is to create a common environmental assessment system for the entire building industry and with the help of this system phase out the use of especially harmful properties from building products.In a large sense BASTA works like this; On the BASTA web site there is a database, to which a supplier can register the company and the company’s products. Only those products with a substance content that fulfil the demands of the BASTA system, is to be registered. As it is the supplier himself that carries out the registration of the company and the company’s products to the system, the BASTA-organisation annually controls that the companies that are registered in the database, fulfils BASTA’s demands.Since NCC is one of the companies that operates BASTA, BASTA is probably going to be the environmental assessment system that is recommended for the company in the future.
CSCW-system ? Framtidens patientinteraktion
Tester på människor, så kallade kliniska studier, är en viktig del i utvecklingen av nyaläkemedel och samtidigt en stor kostnad för läkemedelsföretag. Framförallt när patienternafinns på många olika platser blir processen både dyr och tidskrävande. Real time InteractionPatient Evaluation (RIPE) är ett koncept och en prototyp till ett Computer SupportedCooperative Work (CSCW) system, utvecklat av Elof Dimenäs och Mats Sundgren(AstraZeneca) i samarbete med IT-universitetet. Systemet ska stödja interaktion med patienteri effektstudier och att övervaka medicineringen och dess effekter. Tanken med RIPE är attman ska kunna göra effektstudier med symtomskattning med hjälp av mobiltelefoner ellerInternet.
Sammankoppling av fjärrvärmenäten i Nyköping och Oxelösund : miljö- och systemkonsekvenser
District heating covers most of the residential areas and industries in the twoneighbouring Swedish municipalities Nyköping and Oxelösund. In Nyköping,Vattenfall AB Värme produces heat in a bio-fuelled CHP plant. In Oxelösund,waste heat and use of waste gases from the steel production at SSABOxelösund is the basis in the district heating system.This report examines the environmental consequences of a connection betweenthe two district heating systems. A broad system approach is used and the focusis on environmental effects in the system.A system analysis has been performed on the result of simulations of differentheat and electricity production alternatives. The alternatives simulated wereone where Vattenfall Nyköping covers the base load in the joint district heatingsystem and two where the power plant at SSAB Oxelösund supplies the heatbase load.The conclusion in this report is that the consequences of connecting the twodistrict heating systems can be both positive and negative, depending onsystem boundaries and on the environmental focus.
"Skyll inte på friheten" : en analys av den liberala miljödiskursen i Sverige
The paper is a discourse analysis of the liberal environmental discourse in Sweden today. It is based on articles in two of the main liberal Swedish newspapers, Dagens Nyheter and Sydsvenska Dagbladet, and a liberal periodical, Neo.The purpose of this study is to analyze how the environmental problems that have been produced by the industrialised society, especially global warming, are seen upon in the liberal discourse in Sweden today. The theoretical point of departure is a discourse analysis that as a method seeks to analyze the material to reveal what assumptions the discussion departs from, and what assumptions the discussions reject.The thesis concludes that the main trends in the discussions are to position the environment against the financial system and state that the capitalist system is the only system that can solve the environmental issues. The existing environmental problems are not denied, but constantly belittled and only considered to be a problem if it poses a direct threat to humans. The solution for these environmental problems is believed to be the strengthening of the financial system and the development of new technologies..
Hur forskningsledare styr framgångsrikt: en studie om inom- och mångvetenskaplig styrning vid Luleå tekniska universitet
Inom universitetsvärlden har det på senare tid skett ett ökat intresse för mångvetenskaplig forskning vilket innebär att forskare från olika vetenskapliga discipliner förenas i ett gemensamt samarbete. Vid inomvetenskaplig forskning sker forskning inom den egna disciplinen, men med hjälp av gemensam forskning mellan disciplinerna kan forskningen nå nya höjder då fler infallsvinklar beaktas. Viss kritik har dock riktats mot mångvetenskaplig forskning då det inte är enkelt att sammanföra kunskap från olika områden. Syftet med vår uppsats var att identifiera och jämföra hur inom- och mångvetenskaplig forskning styrs för att nå ett lyckat resultat samt att identifiera vilka problem och möjligheter forskningsledarna anser att ett mångvetenskapligt samarbete mellan disciplinerna innebär. Studien genomfördes med hjälp av en fallstudie av kvalitativ karaktär vid Luleå tekniska universitet där fyra professorer från olika discipliner intervjuades.
Lägenhetsskiljande massivträbjälklag Projektering av bjälklag med förbättrade ljudisolerande egenskaper
AbstractIn the fall of 2003 a project was started in the Swedish building sector that is called BASTA (the building sectors’ termination of especially harmful substances). The project is operated by the building companies NCC, Skanska, PEAB and JM, the Swedish Building Industry and the Swedish Environmental Institute IVL. The purpose of the project is to create a common environmental assessment system for the entire building industry and with the help of this system phase out the use of especially harmful properties from building products.In a large sense BASTA works like this; On the BASTA web site there is a database, to which a supplier can register the company and the company’s products. Only those products with a substance content that fulfil the demands of the BASTA system, is to be registered. As it is the supplier himself that carries out the registration of the company and the company’s products to the system, the BASTA-organisation annually controls that the companies that are registered in the database, fulfils BASTA’s demands.Since NCC is one of the companies that operates BASTA, BASTA is probably going to be the environmental assessment system that is recommended for the company in the future.
A-måttet - En slitageanalys på spårvägsrälsen i Göteborg
AbstractIn the fall of 2003 a project was started in the Swedish building sector that is called BASTA (the building sectors’ termination of especially harmful substances). The project is operated by the building companies NCC, Skanska, PEAB and JM, the Swedish Building Industry and the Swedish Environmental Institute IVL. The purpose of the project is to create a common environmental assessment system for the entire building industry and with the help of this system phase out the use of especially harmful properties from building products.In a large sense BASTA works like this; On the BASTA web site there is a database, to which a supplier can register the company and the company’s products. Only those products with a substance content that fulfil the demands of the BASTA system, is to be registered. As it is the supplier himself that carries out the registration of the company and the company’s products to the system, the BASTA-organisation annually controls that the companies that are registered in the database, fulfils BASTA’s demands.Since NCC is one of the companies that operates BASTA, BASTA is probably going to be the environmental assessment system that is recommended for the company in the future.
Förbättrad Kravhantering med hjälp av Lösningsinriktad Pedagogik
Abstract The purpose of writing this thesis was to improve methods during requirements engineering phase. Usercentred system engineering has some problem areas, which are examined and verified to create a new guideline for developers. This guideline tends to make requirements engineering more effective and help developers create more concrete requirements. It is not uncommon that system development projects ends up with unsatisfied users or delay in deliveries. The reasons are different kinds of communication problems between users and developers during verification of requirements.
Aktiv bullerdämpning i ventilationssystem
Active headsets have been on the market for years and now it is time for something else to enter the stage. The technology of active noise reduction can for exmple also be used in ventilation systems for reducing ventilation noise. An active control system principally consists of four important components, namely the downstream error microphone, the upstream detection or reference microphone, the digital signal processor (DSP) and a loudspeaker. The upstream reference microphone listen to the primary ventilation noise and sends it to the DSP which makes a phase shift to the signal and sends it to the loudspeaker. The loudspeaker sends out the opposite waveform of the incoming one and reduce the primary ventilation noise.