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557 Uppsatser om Alien plants - Sida 9 av 38
Småskalig vattenkraft vid Olofsfors bruksmuseum : Med faunapassage
In Sweden there are 1894 small-scale hydropower plants in operation, which together generate 4.3 TWh of electricity per year according to Swedish hydropower compound (SVKF, 2011). This corresponds to the annual consumption of about 860,000 Swedish households (based on an annual consumption of 5000 kWh). In the mid-1950s there were around 4000 small-scale hydropower plants in operation in Sweden before cheap fossil fuels and uranium competed with them, in the current situation only 1,894 of these are in use. If slumbering small hydropower plants once again would be taken into use and some new ones are built, we would be able to extract about 7 TWh of renewable electricity from these annually in Sweden, representing about 1.4 million households.The thesis intends to calculate and construct a hydroelectric power plant at the existing dam in Olofsfors and give suggestions on how the power station should run during the time that fish migration is greatest in Leduån.The turbine and generator to the station in Leduån at Olofsfors is designed by the height of the fall and the water flow through the dam. The turbine selected for the station is a CK-1000RM turbine with a 4-pole 250 kW generator from Cargo & power turbine Sweden AB, which is expected to deliver 1.2 GWh per year.
Miljöoptimera avfallsindustrin i Sverige : - återvinn restprodukten gips
One of the most common ways to produce heat and electricity in Europe today is by the incineration of waste or combustion of coal. These materials can be very sulfurous and during combustion sulfur dioxide is produced. This is an environmental and health related toxic substance which is why power plants have strict regulations on removing it from the flue gas. Sulfur dioxide is removed from the flue gas by adding a limestone reagent. The sulfur dioxide reacts with the limestone and the synthetic product obtained is ?Flue Gas Desulfurization gypsum?.
Beskrivning av systemfunktioner i kärnkraftverk med hjälp av objektorienterat modelleringsverktyg
In order to facilitate design and maintenance of such a large and complex site as a nuclear power plant, all system functions must be described in a stringent way. In the past, these descriptions consisted of text documents and logical diagrams, but today there are an increasing number of object-oriented programs available on the market which might be used for this purpose. This Master Thesis has made a closer study of one of these programs named Rational Rose. The principal of the program is to facilitate software design and development, not to create models of plants. However, using the program the same way as developing software, specifying actors then gradually extend the model with use cases, use cases diagrams etc, the same methods can be used when modelling plants.
Lönsamheten i vindkraft : en studie om den förväntade lönsamheten i landsbaserad vindkraft
This thesis analyzes the expected profitability in land based wind power plants. The expected profitability is calculated on the basis of a wind power project in Vartofta, Falköping. The information required to calculate the expected outcome is then concentrated to this project, which is in this thesis called project Näs. In project Näs they plan to build three wind power plants, with each an effect of 2 MWh. These wind power plants are very capital intensive investments with a long and uncertain payback time.
Kisel som växtstärkande medel : en litteraturstudie
Sammanfattning
Kisel (Si) är det näst vanligaste ämnet (drygt 25 %) i berggrunden. Bara en del av detta är tillgängligt som monokiselsyra, den form i vilken kisel är upptagbart för växter. Jordens kiselinnehåll är beroende av bergets vittring. Mycket höga halter av kisel återfinns i naturen i vulkaniska substrat (pimpsten innehåller drygt 66 % Si och scoria närmare 47 % Si), i diatomit (ett mineral bestående av resterna från encelliga kiselhaltiga alger, s.k. diatoméer) innehållande 66 % Si, scoria approximatly 47% Si), in diatomite (a mineral consisting of the remainings of single celled algae, diatoms containing < 40 % Si) and in some clays (30-60% Si).
Begomovirus susceptibility in wild Nicaraguan tomato populations
Tomato production is a common and important agricultural activity in Nicaragua. During the last decades tomato producers have suffered great yield losses due to begomoviruses (family Geminiviridae). The genome of begomoviruses generally consists of two circular ssDNA components, DNA-A and DNA-B. Tomato yellow leaf curl virus (TYLCV) is an example of a begomovirus with only one component. An approach to manage the virus epidemics has been to breed a cultivar with begomovirus resistance genes, which have been transferred from wild tomato.
Undervattensvågbrytare - En modellstudie
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.
Tillförlitlighet hos trafikolycksklassificering
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.
New Business Model for District Heating Firms Stabilizing the National Energy System with a Future Variable Electricity Production
The aim of this thesis is to develop a new business model for district heating and cooling firms which can contribute to a stabilization of the Swedish national energy system. The business model is developed for a district heating and cooling firm and is exemplified with Fortum Heat. The theoretical investigation around the topic creates a rigid base for following qualitative empirical studies. Osterwalder?s canvas for business model generation is used together with a Casual Loop Diagram to identify a number of business opportunities which stabilizes the national energy system.
Produktkvalitet på svenskt nötkött : en kartläggning av kvalitetsfaktorer inom IP Sigill
Sigill Quality Systems has been certifying beef since the autumn of 2006 using the brand
name label Swedish Sigill. IP Sigill (the certifying system for integrated production)
encompasses the values: animal ethics, food safety, free range and environmental concerns. Product quality is not yet one of these values, and there is a variation in the quality of Swedish beef. Swedish Sigill wanted to investigate the factors that influence product quality, review which of the present regulations that have an influence on product quality and formulate new regulations with the purpose of enhancing the product quality (sensorial, technological and nutritional quality).
A survey of quality parameters and factors that influence product quality was done in order to establish a scientific foundation to work from.
Min pappa är negerkung : En kvalitativ studie av etniska stereotyper i filmatiseringarna om Pippi Långstrump
The purpose of this paper has been to examine various ethnic stereotypes in two Swedish film adaptations of Astrid Lindgren?s character Pippi Longstocking. I have used a semiotic content analysis and postcolonial theory to investigate: 1) how the ethnic groups are represented in the different materials, 2) if there is a hegemonic relationship between the foreign group and one?s own group, 3) whether there has been a "decolonization" during the twenty years that separate the two films. This study has shown that, in the 1949 adaptation, primarily Africans were produced in a negative light and as biologically inferior in relation to the whites.
Begomovirus prevalence and diversity in the TYLCV resistant tomato cultivar Shanty in Nicaragua
Every year begomovirus infections cause severe constraints to the tomato production in Nicaragua. Extensive yield losses are followed by large economical losses, both for the country and the single farmer. During recent years the use of begomovirus resistant or tolerant tomato cultivars has increased in Nicaragua as an effort to improve yields. Still, begomovirus infection is a large threat to the tomato production. Therefore, ongoing work in Nicaragua is focusing on finding new, better, begomovirus tolerant or resistant tomato cultivars.
Kompensering av reaktiv effekt vid vindkraftverk
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.
Effect of liming and free Ca2+ on Cd uptake of carrots, Daucus carota
The level of cadmium (Cd) in Swedish arable land has increased during the last century and the average concentration of Cd in the plough layer is today 0.23 mg/kg. The increase is mainly due to anthropogenic activities such as phosphorus fertilizing, liming, import of feed, and atmospheric deposition from industrial emissions. Cadmium in the soil will be taken up by crops and is thereby transferred to humans via food. Carrot is one of the crops of concern, both because it may contain quite high Cd concentrations and due to the large consumption in Sweden. In the body, Cd is stored mainly in the liver and the kidneys and may cause several diseases already at low concentrations.
Testplattform för nätverks-RTK i syfte att ge en rikstäckande GPS-tjänst med centimeternoggrannhet
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.