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2546 Uppsatser om Water levels - Sida 19 av 170
Smart Control : En reaktion på EU:s ekodesignkrav
The purpose of this thesis is to assist the Swedish energy company NIBE Energy Systems in their studies of adaptive regulation applicable to electrical water heaters. Due to coming energy classifications of these appliances in the European Union, NIBE Energy Systems needs to use adaptive regulation, called Smart Control, to keep their products in the best possible energy class and remain competitive to the market. By using this Smart Control regulation a 2-3 % improve-ment of efficiency can be credited the system. This is a small number, but heavily needed, since the energy classes are based on the idea that the European Union is provided with electricity from coal condensate power resulting in a 40 % maximum efficiency. Furthermore, doing noth-ing will result in some water heaters not being approved to use on the market from 2015 due to low efficiency.
Rening av avloppsvatten med anaerob membranbioreaktor och omvänd osmos
This master's theses was carried out on assignment from Stockholm Vatten AB as a part of a project developing new waste water treatment techniques. The goal of the theisis has been to evaluate an anaerobic membrane bioreactor for treatment of waste water from Hammarby Sjöstad. The bioreactor has not been heated and the main interest has been to study the gas production, power consumption and the reduction of organic matter and nutrients.The system has been completed with a reverse osmosis unit and a total of four batch runs have been made with good results. The use of reverse osmosis allows nutrient in the waste water to be reintroduced into circulation as the reverse osmosis concentrate can be used as crop nutrient.The membrane unit is of VSEP ("Vibratory Shear Enhanced Processing") type and an extensive membrane test has been conducted. This so called L-test helped determine the most suitable type of membrane for the system to allow a higher ±ux and thus lower power consumption.
Spillvärmeåtervinning ur kylvattensystemet ismältverket på Sapa Profiler AB i Sjunnen
The smelting process at Sapa Profiler AB in Sjunnen generates large quantities of waste heat which is absorbed by the cooling water when the aluminum is cooled down. This paper is the result of a Master?s Degree Project aiming to present the conditions for recycling the waste heat. The cooling water absorbs the heat from the aluminum at an average rate of 600 kW and the paper shows that it can be used to replace electrical power consumption for heating the production plant?s facilities.
Klimatsäkrare städer : klimatförändringar, stadsplanering och översvämningar
The numbers of natural disasters caused by extreme weather are increasing through out the world. A large majority of the research concerning the climate shows that this is a trend that can be expected to continue. At the same time the urbanisation is increasing more than ever and for the first time in history more than fifty percent of the population lives in a city. How we build these cities will have a crucial importance for our adaption to the new climate. In Sweden, our capacity for an adaption are high because of our economic situation as well as our rather well built society.
Stem injection of different nitrogen forms into young Norway spruce
This master thesis has been a pilot study preceding a forthcoming project of a larger scale with the long term objective to separate the direct effect of added nitrogen on soil processes from indirect effects via trees. The aim of this study has been to investigate the allocation of nitrogen following direct injection of liquid solutions into the xylem of 40 year old Norway spruce. The field site is located at Flakaliden (64°07?N, 19°27?E), approximately 60 km northwest of Umeå, Sweden. A total of 18 trees were selected for treatment, equally divided between three treatments, potassium nitrate, glutamine and water (control).
Proppen har gått : En analys av diskursen kring Kultursamverkansmodellen
This essay aims to map the ideas behind the Swedish cultural reform called Kultursamverkansmodellen, and how the ideas are forming a discourse. Furthermore it examines the social praxis on the three levels that constitutes the model. The three levels are the state, the region and culture creators/civil society. This is a qualitative study based on primary and secondary sources collected on the three levels. The theoretical frame of reference is based on institutional theory, on Michel Foucault?s lecture on The Discourse of Language, and on New Public Management.
Nursing technique and growth environment of Rabbit fish (Siganus guttatus) in the area of Tam Giang lagoon, Thua Thien Hue
SummaryIn the area to the east of Hue city, in Vietnam, lays Tam Giang lagoon, one of Asia's largest lagoons, with an area of 22,000 hectares. This lagoon is suitable for aquaculture. One reason for this is because the salinity differs from sweet to salty in different parts of the lagoon. The Vietnamese Government advocates an increase in environmentally-friendly aquaculture and the fish Siganus guttatus (Rabbit fish) is a candidate for this. This fish eats mainly algae and can be cultivated in a polyculture.
Koldioxidavgång vid ekologisk odling på organogen jord
The background of this work is the media discussion about the effect of cultivation on peatsoils on greenhouse gas emissions. It has been argued that row sown and intensivelycultivated crops such as carrots are more likely to emit carbon dioxide than for example grassleys. The association KRAV (an association promoting organic farming) shall, from this yearadapt their environmental policy to be more climate smart and have asked the question if thecultivation of some crops is more climate smart than others? Carbon dioxide emissions fromsoil are due to degradation of organic material and the rate is controlled by microbial activity.The microbial activity is determined by a variety of factors such as temperature, soil organicmatter quality and water content. I have measured the carbon dioxide emission from fourdifferent crops at two different farms.
Antons och Saras årsböcker : En kvantitativ undersökning av två läseböcker i Svenska för årskurs två
In school today pupils come in contact with all kinds of reading books. Education of Swedish reading development sometimes contain reading books organized at different levels of difficulty, with different amount of text. The purpose of the different difficulty levels is to give the less skilled readers an easier book and stronger readers a more difficult book. The purpose with this study is to find out if the book which is classified as more difficult, in reality is the most difficult and if the book which is considered to be easier really is. To find answers to these questions I will examine previous researcher?s theories on difficulty levels in reading books.
Varför sviktar elevers intresse för matematiki de högre åldrarna? : Vilka faktorer ger elever motivationoch lust att lära matematik?
Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.
Naturlig förekomst av arsenik och avskiljning av arsenik från grundvatten : test av olika filtertekniker avsedda för enskilda brunnar
During the last few years the presence of high arsenic (As) concentrations in ground water has been of major concern both internationally and in Sweden. Much evidence has been reported about toxic effects caused by arsenic. The carcinogenic effects and the possibility to measure the toxic impacts at low concentrations made the World Health Organisation (WHO) to reduce the guideline value from 50 to 10 ?g l-1 in 1993. In Sweden the corresponding reduction was implemented in 2003.
Several surveys in Sweden have shown that high arsenic concentrations may occur in ground water.
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.
Nivåbaserat läromedel för läsinlärning : En läsbarhetsanalys av Den magiska kulan
The aim of the study is to examine a book used as level-based teaching material, Denmagiska kulan (Wänblad, 2011), to analyse the progression within and between thedifferent levels, A, B and C, intended for use in grade 1. The material is designed so thatpupils at different levels in their reading development can share the same literature.Another aim is to study the connection between illustrations and text. This literaturestudy is based on both a qualitative and a quantitative method of analysis. Thequalitative method applies a readability analysis with the focus on the graphic form andthe language of the text. The quantitative method measures the LIX (readability index)of the texts.
Självmord - acceptabelt eller förkastligt? : En studie av attityder till självmord i Moskva.
Suicide research has a long tradition within sociology. Parallel to the Durkheimian tradition, seeking the causes of suicide in societal factors, a more cultural understanding of suicide has been emphasized. Attitudes to suicide have been stressed as important for the understanding of suicide mortality levels in different societies. For Russia, where suicide mortality levels are among the highest in the world, an understanding of this kind might be of particular importance.Based on a survey study from Moscow 2004, attitudes to suicide were studied in relation to social, economic and demographic factors as well as to attitudes to other morally disputable behaviors. Suicide attitudes in different age and sex groups in the sample were further compared to suicide mortality levels in the corresponding groups in the population.
Utveckling av hygienfunktioner i diskmaskiner : Desinfektion med ånga
This report is the result of a thesis work in Integrated Product Development, regarding hygienic features in dishwashers and especially disinfection by the use of steam.The thesis is performed at Electrolux Primary Development Dishcare in Stockholm and in collaboration with the Department of Machine Design at the Royal Institute of Technology.The targets of the thesis are to prove the advantages of a technology suitable to implement as a hygienic feature inside a dishwasher and to realize a functional prototype of a differentiated hygienic feature that does not exist on the market today.The process followed to perform the thesis is the process defined for Electrolux Primary Development.The technology chosen for development is disinfection by heating the water on the surface of the dishware, by the use of steam.A number of tests on how steam behaves when injected into the dishwasher tub have been performed, providing the results that have been taken in consideration when designing the prototype.The prototype consists of a pipe system provided with nozzles to eject the steam into the upper parts of the dishwasher. Tests of the final prototype show that thermal disinfection of water in a dedicated area of the tub can be reached within 9 minutes. The operation requires 0,17 liters of water and consumes 0.2kWh..