Sökresultat:
676 Uppsatser om Wind load - Sida 33 av 46
Analys av lageregenskaper utifrån mätningar i testrigg
Vertical hydropower units has a rotating mass of up to 1000 tons. For the generator and turbine to work well the rotating system is required to be centered in relation to the surrounding structure. This is achieved by means of radial bearings. The dynamic characteristics of these bearings have a strong impact on the overall rotational dynamics of the total system and thus influence the vibrations in the unit. At Vattenfall Research & Development in Älvkarleby ongoing research is taking place on how the bearing parameters should be represented in the rotor dynamic calculations.
Dammet, vår minsta gemensamma nämnare : En känsla av tillhörighet
Dust, our smallest common denominator Charlotta Lindvall ABSTRACT I find it fascinating to know that we are all made of the same material as the stars and that everything is connected to each other and in a constant movement and transformation, a recycle of material. We are all made of stardust. In fact all life is sprung out of dust.In my essay I investigate the dust and ask the question if there are any traces in the dust. I look at the history of the dust and how it has affected us and our world through the decades. What does this small and airy but oh so unappreciated dust tell us? Why do we want to get rid of it? Is it possible to find a sense of belonging in the big context by investigating the dust and its origin and could I transform such a low material as dust into something magic that makes people reflect on our origin and belonging and how everything is connected? In my work I use dust as a material and in the essay I compare my work with other artists who have worked with dust as a material.Dust is everywhere because its source is from everything.
Resultat av tjugofem års mätningar av Cs-137-halter i älg i Uppsala län
At the end of April 1986 reactor number 4 of the nuclear power plant at Chernobyl explod-ed and large amounts of radioactive particles were then released into the atmosphere due to both the explosion as well as the consecutive fire of the graphite core. A cloud of radioac-tivity was spread over the northern hemisphere, including Sweden, due to the prevailing wind directions. The radioactive particles were washed out from the cloud by rain and snowfall in some areas of Sweden and deposited on the ground. The deposited radionu-clides, primarily cesium and iodine isotopes, were later absorbed into the soil and taken up by the roots of the plants. Some of these radionuclides, like 137Cs, still persist in some of the terrestrial ecosystems at relatively high concentrations which lead to contamination of the meat of moose, roe deer and wild boar even today.The two municipalities Heby and Uppsala, in the eastern part of central Sweden, experi-enced a relatively large deposition of 137Cs which resulted in high levels of 137Cs in moose and other game.
Utvärdering av statistiska analysmetoder för detektion av partiell nedisning av anemometrar
Detaljerad information om vindförhållandena på en site är en nödvändighet för att göra beräkningar av lönsamhet i ett vindkraftsprojekt. Mätningarna behöver vara kontinuerliga och så korrekta som möjligt. Därtill bör de göras under minst ett års tid eftersom vindförhållandena på en plats är säsongsberoende. Under vintertid och framför allt på högre latituder eller altituder, kan mätutrustning påverkas av nedisning. En nedisad anemometer kan ge databortfall eller felaktiga mätningar.Identifiering av felaktiga data är en viktig del av analyseringsarbetet eftersom risken annars är att vindförhållandena på platsen underskattas.
Pilotmodeller till flygmekanisk simulator för JAS 39 Gripen
AbstractSAAB has for a long time used user controlled pilot models in ARES. ARES is a simulation tool used in the desktop environment for simulations and calculations of the JAS 39 Gripen fighter and other aircraft. ARES stands for ?Aircraft Rigid body Engineering Simulation?. To work with these pilot models has been both time-consuming and inefficient.
Work-life balance och verkstadschefer
En hel del tidigare forskning tyder på att ha en balans mellan arbetsliv och privatliv är viktigt för att uppleva ett psykiskt välmående samt för att kunna prestera bra på arbetsplatsen. Då verkstadschefer på ett industriföretag genomgår ett stort förändringsarbete undersöktes hur fem manliga chefer upplevde sin balans mellan privatliv och arbetsliv. Delsyften med studien var att undersöka hur chefens roll i privatlivet påverkade balansen, i vilken grad stöd hemifrån påverkade balansen samt vilka konsekvenser en balans eller konflikt skulle kunna få. Studien genomfördes kvalitativt, med en semistrukturerad intervjuguide, där samtliga respondenter var påverkade av förändringsarbetet. Resultatet visade att det fanns verkstadschefer som upplevde en konflikt mellan arbetsliv och privatliv men även de som upplevde en balans.
Vindkraft i motvind : En studie om kommunikation kring ett vindkraftprojekt
Etableringen av en vindkraftspark är sällan okontroversiell och involverar en stor mängd intressenter i form av företag, myndigheter, föreningar och privatpersoner. I den här Cuppsatsen studeras ett planerat vindkraftsprojekt på Mästermyr utanför Hemse på Gotland. Mästermyrprojektet är ett tydligt exempel på en lång och utdragen planeringsprocess som i slutändan ledde fram till att byggtillståndet överklagades och att projektet lades ner. Kommunikation i vindkraftsprojekt har i rapporten Wind energy and local acceptance: Howto get beyond the Nimby effect identifierats som ett effektivt vapen mot NIMBY-effekten. NIMBY står för ?not in my backyard? och med detta menas att människor och organisationer ogärna vill ha vindkraftverk i sin närhet även om de över lag är för vindkraft.Uppsatsens syfte är således att studera kommunikationen i Mästermyrsprojektet för att svara på vad i processen som leder fram till att byggtillståndet överklagas samt vilka möjligheter att påverka utbyggnadsplanen som intressenter har haft.
Upplevt hälsotillstånd och arbetssituation relaterat till ländryggsbesvär bland poliser
SAMMANFATTNINGLändryggsbesvär är generellt vanligt förekommande i befolkningen och samhällsekonomiskt kostsamt. Riskfaktorer för ländryggsbesvär beskrivs vara flerdimensionella, där nämns främst arbetsrelaterade och psykosociala faktorer. Poliser är en yrkesgrupp där arbetssjukdomar rapporteras vanligt förekommande oavsett kön. Trots det är polisers arbetssituation dåligt utforskad. Syftet med studien är att kartlägga upplevt hälsotillstånd och arbetssituation bland utryckningspoliser med fokus på ländryggsbesvär, som underlag för preventiva åtgärder.
Bestämning av dagvattenflöden i Knivstaåns avrinningsområde
The purpose of the thesis was to map the hydraulic load on the Knivsta river from stormwater runoff, and build a platform for further studies of pollution loads on the rivers ecosystems. New residential areas are planned to be built in Knivsta municipality and it will have an impact on stormwater flows to Knivsta river. To examine the impact this will have, simulations were made in the area as it stands today and after expansion work. The work includes calculation of flows from the populated areas but also from the catchment area around it consisting of woodlands and fields. Because of expected climatic changes which may affect rainfall, the simulations have been performed with different return periods for rainfall data.
Eftermarknadens möjligheter : En studie av Swecon AB:s tjänsteutbud
ProblemThe manufacturing industry is a mature industry where the profit margins are small and the competition is hard. This makes it hard for both manufacturers and resellers to gain market shares and reach reasonable profit margins only by selling products. Therefore Swecon who is reseller for Volvo Construction Equipment tries to find alternative methods and ways to increase their profit. An alternative source of income could be to develop the range of services that are connected to the ground products.PurposeThe purpose of the thesis is to examine how Swecon in southern Sweden can improve their offers of existing services connected to the ground product and investigate the demand of new such services.MethodThis study is based on a qualitative study of five of Swecons local offices and five of Swecons customers. The empirical framework is mostly based on personal interviews but in some cases information was retrieved by using phone interviews.
Personlig träning på egen hand
AbstractThe purpose of this essay was to determent if the authors? idea to replace a personal trainer with a training program, which is provided by software, is viable and if there is a market for such a product. The method that was used, included eight people who enrolled in a training program which were designed by the authors in Microsoft excel. The programs were based on principals of periodization, and included the phases: anatomic adaptation, hypertrophy, maximum strength and muscle definition. The training program was personal and based on individual goal setting.
Timeliness cost for agricultural sprayers : weed control in cereal crops
Evaluation of machinery costs is necessary for selecting appropriate farm machinery. Timeliness cost due to untimely operations is an important component of machinery costs. Timeliness costs can be high for crop sprayers, since pesticide application must be carried out within a short time interval. This Master thesis investigated the timeliness cost and the probability of a suitable workday for spraying. Timeliness factors were estimated for four different crops (oats, spring wheat, winter wheat and barley) using historical weed trial data.
Optimal välfärd och hälsa för kalvar :
In order to optimize calf welfare and health it is important to know the behavior of cattle in free ranging conditions. When the cow is about to give birth to a calf she will leave the heard about 12 hours before. It is then rather obvious that isolating the cow about calving time in a single pen is imitating the cows? natural behavior. To save space and minimize building cost it?s common that the farmers build calving pens for four of five cows especially at larger farms.
Analys av off-design prestanda för ett absorptionskylsystem
This master thesis project at KTH is performed in the Mechanical and Aerospace Engineeringdepartment at University of Florida (UF). The thesis is a small part of a gas turbine researchproject where a vapour absorption refrigeration system (VARS) and a high pressure regenerativeturbine engine (HPRTE) are integrated together. The main objective is to build a computermodel of the VARS. The computer model is supposed to be used to analyse the off-designperformance of the VARS and should also be easy to integrate as a subroutine in a more complexsystem model. To model the VARS some knowledge of the absorbent/refrigerant mixture had tobe well known, in this case a mixture of ammonia and water.
Eco Screening : Framtagning av ett verktyg för kartläggning och utvärdering av produkters miljöbelastning vid ÅF EcoDesign Center
The report describes an ecodesign thesis performed by the author at the ÅF EcoDesign Center. The basic idea of ecodesign is to develop products with a minimized environmental load, without neglecting other significant product aspects such as function and price. During the last couple of years the public interest in environmental friendly products has increased, which has made it possible for companies to make a profit from their investments in ecodesign. To meet the increasing market for ecodesign services ÅF started the ÅF EcoDesign Center, where the company has gathered all of their competence in ecodesign in order to help companies to become greener. The task was to develop a tool for an Eco Screening.