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2357 Uppsatser om Water-living organisms - Sida 12 av 158
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.
Turbiditet i dricksvatten: mätningar i Luleå kommuns
distributionssystem
Turbiditet är ett mått på partikelinnehåll i dricksvatten samt ett sätt att beskriva vattenkvaliteten. Vattentäkten i Gäddvik, Luleå kommun, har periodvis hög turbiditet. Syftet med examensarbetet är att utreda orsaker till turbiditet i dricksvatten, från Gäddviks vattentäkt till konsumenter i Luleå kommun. Målet är att ge svar på vilken typ av partiklar som orsakar turbiditen. Analyser utfördes före och efter filtrering av dricksvatten.
Idiopatisk cystit hos katt : en retrospektiv studie
Lower urinary tract diseases are a common problem in cats all over the world. The symptoms are for example dysuria, pollakuria, stranguria, periuria and hematuria. In approximately two thirds of these cats the underlying cause is not known and the disease is therefore called feline idiopathic cystitis (FIC). We need to know more about the disease to get a consistently effective treatment and prevention.
A retrospective study was performed in 50 cats with symptoms of FIC and where other causes of inflammation were ruled out. Data like breed, age, sex, body weight, feeding, therapy and therapeutic results were collected, also if it was an indoor or outdoor cat, duration of the symptoms, if there was any stress and if the cat was living with another cat.
Simulering av översvämningar i Nedre Dalälven
Mosquitoes are found in extremely large numbers in the lower parts of the River Dalälven. In the year 2000 the mosquito nuisance was especially high, resulting in foundation of the Biological mosquito control project. Since 2001 mosquito larvae are controlled by using a biological pesticide BTI (Bacillus thuringiensis ssp israelensis). The mosquito fauna in the area is dominated by flood water mosquitoes, a group of mosquitoes that are very aggressive and form new generations of mosquitoes during every single flooding event during the summer. To be able to efficiently control the mosquitoes it is essential to know the extension and locality of the flooding.
Finngruvan - Uppföljning av vattenkvalitet, analys avavrinning och recipienter i området efter gruvdrift
This thesis raises the problem with acid mine drainage around the closed mine Finngruvan.The purpose of the investigation was to compare metal content in surface water in the areaand its catchments between year 2010 and 2003, also to make calculation of specific runoffand metal load, furthermore determine the recipients in the area. Surface water samplingwhere preformed at the same place as 2003 and also at a few other places of interest. Adigital elevation file were used in GIS to calculate the area of the watersheds in the region,observations in the field where also made. The collected data were used to make comparisons,calculations and conclusions. The result showed that the surface water 2010 had somewhatlower metal concentrations.
Hur mår dagens skolbarn? : En studie av skolbarns hälsa inom Umeå kommun.
The purpose of this survey was to map out the health pf some of the 11 and 12 years old children in the city of Umeå, as well as to find out what factors intend to influense the children´s health. A questionnaire was distributed in four 6th grade classes whitin the municipality of Umeå. Two of the schools were located in the city while two were located in near villages. This selection was decided in order to map out diffrences in health related to the children´s home environment. 80 pupils took part of this study.
Development of Liquid Cooling for PCs
In recent years, existing solutions for cooling personal computer CPUs have been supplemented by a new product category, factory sealed water cooling loops. These systems, consisting of a water block with an integrated pump, a fan and a radiator, perform well compared to the air cooling solutions but are less effective than larger, custom-built water cooling systems.This project aims to explore the most important aspects of a factory sealed system and to identify possible cost-effective enhancements of the performance.The most significant differences between the different groups of water cooling loops are the block design and the pumping power. The performance of both categories is also largely dependent on the fan power, but increasing fan power has a large negative impact on the noise level.Both radiator size and fan model choice appear, in tests, to be relatively unimportant, presuming that the noise level is kept constant. The position and direction of the fan, however, has significant impact on both the temperature and the sound level.Water blocks can be designed in several different ways, both regarding the heatsink design and the flow direction. In simulation, flow with the inlet centered above the heatsink result in considerably lower pressure drop and slightly higher temperatures than flow through the block, for heatsinks with fin arrays.Creating a competitive product in this product segment certainly seems possible, as there are performance-increasing changes to be made that seemingly has little impact on the production cost.
Det kan vara farligt att ligga lågt - om stadsplanering inför stigande vattennivåer : Exempel från Göteborg, Kristianstad och Arvika
In this study is being examined how cities can be planned in the face of rising water levels and extreme weather, due to the changing climate. The starting point has been to investigate how the problems can be tackled and how the positive sides of water in the city can be strengthened, and synergy effects and greater sustainability be achieved thereby. The method has been literature studies and case studies containing interviews and visits. Göteborg, Kristianstad and Arvika have been studied for discussions and ideas about adaptation. Today, building near water is very popular which brings both advantages and disadvantages.
Entreprenörers levnadsstandard: en fråga om personlighet : Kvantitativ undersökning av den materiella levnadsstandarden hos egenföretagare i Sverige
Earlier quantitative entrepreneurial studies with a focus on poverty rate has centred their arguments and analyses entirely on income differences which has resulted in a high poverty rate among self-employed. Their results shows that variables such as age, gender, hours of labour and structure of the household significantly affect the poverty rate among self-employed. In this study we aim the focus on material living standards instead of income differences, thus using a more representative approach while studying entrepreneurial poverty. The purpose of the study was to examine how personality traits (big five) affect the material living standards among the self-employed in Sweden, using a group of employed as a control group. Variables earlier known to affect the poverty risk among self-employed where used as control variables together with education and household income.
Hur påverkas bentiska funktionella födogrupper av kalavverkning? : Effekt på abundans, samt återhämning, av funktionella födogrupper efter kalavverkning kring små vattendrag.
Forestry affects most of the forest-covered land in Sweden. In the landscape, the most common stream type is headwaters, which are important sites for many processes and organisms in both the terrestrial and the aquatic ecosystems. The aim of this study was to investigate how the abundance of benthic invertebrate functional feeding groups in headwater streams develops after clear-cutting and if it also is possible to detect a change in the composition of feeding groups. The study also attempts to determine what factors have an effect on temporal changes in abundance of these groups. For the study, 11 sites in northern Sweden were sampled for benthic invertebrates using a Surber-sampler, and for each site canopy-cover and pH was obtained.
Jag styrs av pengarna -som jag inte har : En litteraturstudie om hur personer med psykiskt funktionshinder upplever att ekonomin inverkar på deras vardag.
Background:Persons living with a mental illness often have to put up with a financial disadvantage. Their ability to work is often limited and because of that they have to rely on the welfare reform to get an income. This income is often low compared to other citizens which by itself is something strongly associated with mental illness. Purpose: The purpose in this study was to describe how people living with a mental illness experience that their economic situation has an impact on their daily life. Method: This study is a literature review containing nine scientific articles from previous research.
Hur kan blöt vetedrank lagras, hanteras och utfodras till mjölkkor? :
Distillers? grain is a by-product of ethanol production. Corn, wheat and barley are the grains
that are generally used in the distillery process. Distillers? grain is rich in protein and
phosphorus.
Simulering av översvämningar i Byälven
Severe floods caused by heavy autumn rains in year 2000 raised the question whether measures to reduce the damage from high water levels, in the area surrounding lake Glafsfjorden and along the river Byälven down to lake Vänern, are possible. One option is to reduce flow resistance along the river and thereby lower the maximum water level a given inflow would cause. Good knowledge of hydraulic and hydrological conditions is necessary in order to estimate the effect of such flow-reducing measures. In order to quantify such effect a 1-dimensional hydraulic flow model has been set up for the river Byälven using the software package MIKE 11. The model is more detailed, especially concerning topography and bathymetry, than earlier models used for studies of the river.
Konduktivitet i vattendrag som indikator på sura sulfatjordar
Increasing attention is being given to acid sulphate soils wherever they occur. The problems that leaching sulphate soils gives with significant lowerings of pH and mobilization of heavy metals influence large spectra of our society from fisheries to agriculture to construction. Mapping these soils is consequently of great importance and the methods of doing this is very much lacking in function and precision. This study was therefore carried out to investigate whether conductivity in running water can be used as a simple instrument to identify acid sulphate soils in the catchment. 31 coastal streams in the county of Västerbotten were analyzed for different catchment properties such as occurence of marine sediments and basic water chemistry including conductivity and sulphate.
Värmeåtervinning ur spillvatten i befintliga flerbostadshus
Drain water heat recovery is an uncommon measure in multi-unit residential buildings. There istechnology available for the purpose but the knowing and experience of the heat recovery systems islittle. The purpose of this thesis is to evaluate the future potential of drain water heat recovery inmulti-unit residential buildings.A major part of the multi-unit residential buildings in Sweden were built during modernismen andrekordåren (1940?1975). Many of the buildings have worn out drain and water supply systems andmany are in need of a general refurbishment.