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436 Uppsatser om Biomass losses - Sida 12 av 30

Mätning av axiella magnetiska läckflöden i vattenkraftsgeneratorer

This thesis describes a method of measuring axial magnetic leakage flux in an operational hydropower generator. Axial magnetic leakage flux is the magnetic flux at the ends of a rotating generator, which goes through the stator parallel to the rotor axis. This flux can cause circulating currents in the stator iron, giving rise to losses, and can in the worst case overheat a generator, causing it to melt down. To measure the axial flux, and how it affects the generator temperature, a measurement system was constructed on behalf of Vattenfall. The system consists of search coil sensors and a signal-processing unit with amplifiers and active filtering.  To confirm the behaviour of the axial leakage flux and the functionality of the measurement system, a test installation was made.

Integrering av pelletsfabrik med Rya kraftvärmeverk i Göteborg : en teknisk och ekonomisk utredning

Göteborg Energi has a surplus of district heating during spring, summer and fall. The heat surplus is due to a constant production of waste heat from oil refineries and heat from waste incineration over the year. It would be desirable to increase the demand for heat and the uptime for the newly built combined heat and power generation plant, Rya Kraftvärmeverk. One alternative could be to integrate Rya Kraftvärmeverk with a pellet production facility. By producing heat, electricity and pellet in a joint process the energy use can be decreased.

En modell för att kostnadseffektivt öka produktionen inom aluminium-bearbetning

The purpose of this study is from a case study develop a model that aims to cost effectively improve productivity in a manufacturing production process. The study highlights the importance of having knowledge about customer needs and using a holistic process perspective when improving productivity to identify the relations between the process stations and by this find problems that cause waste and losses in productivity. Tools and methods used to make production more efficient such as single minute exchange of die, spaghetti diagram, 5s and master production schedule is presented an applied in the model to see how these effect costs, productivity etc.Maintenance effects on quality and productivity in a manufacturing company will as well be covered in this thesis. The results and conclusions finally reveals how the process improvement tools, maintenance and production planning for example effects each other and why it is important to establish an attitude in the company where continuous process improvement should be emphasized..

Kvävemineralisering från stallgödsel beroende på olika grad av inblandning i mark

The impact of the distribution in the soil volume of two farm manures on the net mineralization and immobilization processes of nitrogen were studied in an incubation experiment. Cattle slurry and broiler litter were placed in the soil with three procedures for incorporation including placement on top of the soil (TOP), in the middle of the soil (MID) and mixed homogenously with the soil (MIX). During the two weeks of incubation, few significant differences in net mineralization were seen between TOP, MID and MIX. However, there was a tendency that MIX led to a larger net immobilization of N than placement at one point (TOP and MID). This is also the result in the literature.

Från alger till biodiesel - Den italienska drömmen?

This project aims to investigate whether algae can be used for biodiesel production in Italy. Algaes are a good option since they are fast growing and do not occupy arable land. The aspects that have been considered are growing, harvesting, which algae strain that is most suitable, extraction of oil, the production of biodiesel and where in Italy this could be possible due to climate. Cost? and energy calculations have been made to investigate if biodiesel produced from algae would be profitable. During the production of biodiesel there are several residues obtained. When the oil has been extracted from the algae, biogas is produced from the residual biomass by anaerobic digestion and then the electricity that can be produced is supplied to the production of biodiesel.

Resultatmanipulering: En studie av förekomsten av resultatmanipulering i svenska företag

The aim of this thesis is to examine the existence and prevalence of earnings management in Swedish companies. Theoretical frameworks often suggest that there are strong incentives to practice earnings management. The research area of earnings management has, to date, mainly focused on detecting earnings management. However, to our knowledge, no such studies have been conducted on Swedish companies. This thesis provides evidence of the existence and prevalence of earnings management in Swedish companies.

Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs

Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation. Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.

Sha Jun

The agriculture in Sweden today uses chemical substances to control vermin, weed and diseases. This usage shows through polluted subsoil water and trace elements in the food we eat. There?s a risk that additional symptoms will arise in the future. Our product Sha Jun, developed in 2006-2007, is an attempt to try and minimize the need of chemicals in the agriculture. The idea started with the attempt to minimize the usage of pesticides on the cropland.

En jämförelse mellan får- och nötkreatursbetade hagmarker med avseende på populationsstorlek samt artsammansättning hos dagfjärilar och örter

Many of Europe?s day-living butterflies have shown decreasing populations during the last decades and many species are threatened. Many butterflies are dependent on managed semi-natural grasslands because of their richness in nectar sources and host plants for the butterfly larva. Swedish pastures are mostly managed through grazing. The number of cattle in Sweden have been decreasing while the number of sheep in the country increased by 30%.

Integration ? allas vårt ansvar? : Tjänstemän och politikers reflektioner kring integrationen i Nyköpings kommun

This thesis is based on thirteen qualitative interviews with civil servants and politicians. The purpose of the study is to research these informants? attitudes towards integration and their reflections about immigrants? lower chances in an ethnically segregated housing and labour market. The theoretical frame of references is based on social constructionism and focuses on including and excluding power structures. The empirical material provides both structural and cultural explanations to immigrants? problems as regards inclusion in Swedish society.

Riskfaktorer för Staphylococcus aureus i mjölk och på has hos mjölkkor :

Mastitis is the most common disease of dairy cows. Mastitis can be painful for the dairy cow and causes economical losses for the farmer. These losses are due to decreased milk production, more working hours for the farmer, treatment costs and possible costs due to culling of the cow. The udder inflammation, mastitis, is often caused by bacteria infection. One of the most common bacteria found to cause mastitis in Sweden is Staphylococcus aureus (S.

Småskalig säsongslagring av solenergi för uppvärmning av bostäder : Simulering av lagerutformning och konsekvensen av adderade uppvärmningsbehov motsvarande en pool och ett atrium

The sun is a huge energy source with great potential of providing energy to the heating of homes and other buildings in an environmentally sustainable manner. In order to provide buildings with energy from the sun it is necessary to transfer the energy supply over time to when the demand arises. By storing the heat in a seasonal storage, solar energy from the summer can be used in the winter when the demand for heating is greatest.Today's existing plants are mainly in Europe and particularly in Germany. These facilities are designed to supply heat demands greater than 400 MWh and covers about 40-50 % of this need which consists of energy for space heating and domestic hot water. How much of the heat demand that is covered, the solar fraction, is partly due to losses from the storage which in turn is connected to the surface area of the storage.

Om krigsupplevelser och krisbearbetning : en studie om hur några svenskar från Libanon upplevde kriget mot Libanon sommaren 2006

This study is a qualitative investigation where surveys where performed on five Swedes from Lebanon. The purpose with the survey was to learn how these persons were affected by the war against Lebanon in the summer 2006, how they reacted to it and what measures they took to overcome their crisis. The result shows that the state of crisis of the interviewed persons was caused by several factors, such as the war being both unexpected and intensive. Other causes was the worry that their children would be hurt by the effects of the war as well as the material and human losses that the war brought.The interviewed persons responded with both negative and positive reactions, which may have affect their recovery process. Some of them where offered physiological support in Sweden by their municipalities.

Vådabekämpning : Kan det förhindras?

Vådabekämpningar är inget nytt fenomen när det kommer till militära operationer. För att kunna lösa detta problem så måste man ta reda på vilka de största orsakerna till vådabekämpning är samt vilka lösningar det finns för att minska risken. I denna uppsats har det genomförts kvalitativa litteraturstudier om fenomenet vådabekämpning, från Operation Desert Storm och framåt. Syftet med uppsatsen är att studera hur arbetet med att förhindra vådabekämpningar skulle kunna se ut, samt ta reda på vilka de största anledningarna är till att vådabekämpningar uppstår. Analysen visar att det finns en rad olika orsaker till att vådabekämpningar uppstår. Vidare så visas ett antal åtgärder som kan vidtas för att minska risken för vådabekämpningar. Resultatet visar på att det går att reducerar riskerna, men att fenomenet aldrig helt kan försvinna..

Försäkringsbolags kostnader för reparation av fuktskadade badrum

The purpose of this report is to compile and examine the cost of renovation of moisture-damaged bathrooms, to derive a target price. The target price can then be used by insurance companies to estimate the ultimate cost of future bathroom renovations.       The method is based on the compilation and comparison of the cost of repairs of previous water damage in bathrooms. The calculations compiled based on repair estimates for different insurance losses from one of the leading insurance companies in Sweden.       The result shows the average price per square meter of floor area for different sizes of bathrooms. The average price is the basis for the estimate of future renovation costs of bathrooms. The results further show that the bathroom finishes, area and the distance between the entrepreneur and the location of the renovation have great impact on the final repairing cost.

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