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946 Uppsatser om Grid technique - Sida 11 av 64

Utveckling och tillämpning av en GIS-baserad hydrologisk modell

A distributed hydrological rainfall-runoff model has been developed using a GIS integrated with a dynamic programming module (PCRaster). The model has been developed within the framework of the EU-project TWINBAS at IVL Swedish Environmental Research Institute, and is intended for use in WATSHMAN ? a tool for watershed management developed at IVL. The model simulates runoff from a catchment based on daily mean values of temperature and precipitation. The GIS input data consist of maps with soil type, land-use, lakes, rivers and a digital elevation model.

Ammoniakförluster vid flytgödselhantering : myllning och surgörning som metoder för att minska avgång vid spridning

The ammonia emissions are an environmental issue since they contribute to eutrophication. By far the largest source of ammonia emissions is manure from agriculture and should therefore be reduced. Loss of ammonia is not only negative for the environment but also to the farmer who loses nitrogen that could have been used by the crop. The focus of this study has been emissions from spreading slurry where the loss can vary widely depending on slurry-, soil-, and weather conditions. There are mainly two different ways to reduce the emissions. One is to inject or mix the slurry into the ground to avoid air contact. The other way is to use acid to reduce the pH in the slurry to a level between 5 and 6 where the equilibrium is so strongly pushed to NH4+ that hardly any NH3 can be lost.

Trafiken till Göteborgs södra skärgård - En annorlunda kollektivtrafik

Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.

Ambulanssjuksköterskors upplevelser under ett bestämt ambulansuppdrag då LUCAS? användes

Aim: The aim was to investigate the ambulance nurses experiences during a specific ambulance missions that led to usage of LUCAS ?.Method: Participating ambulance nurses were randomly assigned from a total sample group of 12 women and 39 men. Five women and five men participated. Qualitative interviews were conducted, where the Critical Incident Technique approach was used. Collected interviews were valued using qualitative content analysis.Result: Interview texts were divided into three domains, 10 subcategories could be identified which were sorted into three categories.

Rostfritt stål som ett alternativt material till koppar i tappvattenledningar för bostäder

Today?s wind power plants are only compensated for their reactive power consumption at no-load. As the wind power plants grow bigger the amount of reactive power they need also increases. This is no longer a problem that can be ignored, especially as the net owners are beginning to charge the reactive power they transport.In this thesis a couple of different methods of compensation and their prices will be discussed and evaluated. Problems, such as self-excitation, that can occur if one fully compensates the wind power plant will also be brought to surface.

Analys av det nordiska kraftnätets påverkan på det svenska elspotpriset.

During the last few years, there has been a lot of debate regarding the price ofelectricity on the Swedish market. According to a recent survey from Sifo, anon-bias governmental institute for consumer research and testing, the priceof electricity is what worries Swedish households the most. An investigationof the eciency of the Nordic power grids inuence on the Swedish spotprice is therefore both relevant and valuable. Three quarters of all electricityproduced in the Nordic region is traded at the Nord Pool Spot power market.This survey examines how much of the variation of the swedish spot pricecan be descried by the variation of the nordic system price and how much iscaused because of ineciencies in the power grid. Primarily, linear regressionwith adjustments for endogeneity and heteroskedasticity has been used in orderto analyze data obtained mainly from Nord Pool Spot and Vattenfall AB.The results show that the variation of the system price can account for all butabout 40% of the variation in the Swedish spot price.

Mätramar för vederlagsmätning och timmersortering på sågverk

The measuring of logs is important in the sawmills process to the sawn products. The technology of automatic wood measurement is continuance developing. This study has the purpose to see how the different techniques and the routines works of measure frames for determining of wood value and sorting in sawmills. The study is performed as a literature study and a survey. The survey includes some of the Swedish sawmills that produce more than 10 000 cubic meters sawed products per year.

E.ON:s transformatorflöde - en studie av återanvändningen av transformatorer i projekt krafttag

Problem StatementAfter the hurricane Gudrun in January 2005 EON Elnät Sverige AB started the project KRAFTTAG, were 17,000 km of the airborne power grid shall be replaced with cables underground. The transformers in the airborne power grid shall be dismounted, renovated if necessary and then conveyed to stations, of type kiosk.Additional new transformers, more than planned, have been bought. This is due to the dysfunctional transformer flow from the demolished power supply to projects, were the new power supply is built, the general picture is complicated, since the reconstruction involves other companies and many employees at E.ON.PurposeThe purpose of this master thesis is to map and understand the existing transformer flow. The objective is to make a recommendation on how to increase the level of E.ON? s transformer recycling.Methodthe authors have worked with a system approach, including both qualitative and quantitative data.

Urban Building vid Hornsbruksgatan

knyta samman gata och park.två huskroppar formade av stående vinklade skivor så att den visuella och fysiska kontakten mellan det urbana gaturumet och parken blir självklar.Parametrarna som styrt projektet är siktlinjer, flödesanalys och ett grid på 800x800mm..

Kartläggning av nätförlusternas storlek inom Mälarenergis elnät

Energy losses are an essential part of a power grid company?s costs. From anenvironmental and economic perspective, it is important to reduce these costs. Toknow where efforts should be deployed, it is important to have good knowledge ofwhere in the network losses are situated. When creating network tariffs, there is alsonecessary to have a correct distribution such that the network customers that use acertain part of the network, only pays for the network losses in this area.

Utformning av kulvertgaller i lösdriftsstall med hela golv för mjölkkor :

Summary The size of the Swedish dairy farms increases and also the demands for rational manage-ment of the herd without affecting the animal welfare enhance. One way to handle the manure in the cow shed alleys is to have automatic scrapers. In this system the scraper has to get rid of the manure somewhere. The most common way of doing that today is to let the scraper deliver the manure under some kind of gate or covering over the manure culvert. When the scraper goes under the gate or the covering there is a risk of squeezing animals and farmer.

SPICA - ARISTO JÄMFÖRELSE studie av analysprogram med avseende på spånningskollaps i elektriska kraftsystem

Safe operation of a large synchronous power system as Nordel is not an easy task.There are several aspects to take into consideration. This thesis focuses on the problems due to voltage collapses in a transmission system.The ability to foresee an upcoming collapse is vital to maintain stable operation of the grid. The grid operator at Svenska Kraftnät (SvK) uses the computer program SPICA to predict the maximum transfer limit at specified transfer sections. SPICA uses actual states from the grid to predict the transfer limitation, and a quarter later a renewed estimate is produced and so on. This means that the operator can se his transfer limits vary every fifteen minutes.Our task in this project is to validate the accuracy of the limitations obtained by SPICA.

Accordeonets och dragspelets standardbas - Kombinerade ackord/grundbasar

The Stradella system on an accordeon is a complicated construction. It has readymade con-nected chords, these are major, minor, seventh and diminished seventh. To reach other vari-ants of chords you have to combine chord/bass buttons. Which advantages and disadvantages do the use of combined chords/bass buttons mean? How is the pedagogic work affected by using the combined chords/bass buttons? I have interviewed four musicians/teachers to learn about this technique.

Utvärdering av Di35M-PrLO-projektion av armbågsleden för utlinjering av mediala processus coronoideus hos hund :

The aim of this study is to evaluate an alternative projection of the Medial Coronoid Process (MCP) of the canine elbow joint. The projection (Di35M-PrLO) was, to my knowledge, first mentioned in an article by Haudiquet et al in 2002. In that article the projection was tested in vitro, and a good sensitivity was showed for the Medial Coronoid Process. The projection might be helpful in cases of suspected Fragmented Coronoid Process (FCP) . This study is divided into three parts. The first part is an in-vivo test of the projection, including technique and subjective evaluation of the outlining of the MCP.

Dygnsvariation av metanemission från en anlagd våtmark

The aim of the study was to investigate if methane emission in a constructed wetland changed in a diurnal pattern correlating to temperature, humidity or light conditions. The gas measurements were carried out with a static chamber technique. The wetland (in Nykvarn outside of Linköping, Sweden) takes care of wastewater to reduce the nitrogen loads. Measurements were carried out at three different occasions in the summer of 1998 on two sites in the wetland. One site was close to the inflow, inhabited by Lemnaceae, and another site was located further downstream inhabited by the emergent macrophyte Typha latifolia.

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