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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Praktisk framställning av biogas : konstruktion av en fungerande demonstrationsapparat

Callstam, Christian, Hedlund, Henrik January 2004 (has links)
No description available.
12

Vindkraft- En klass för sig / Windpower- A class of its own

Nordqvist, Sandra, Öhman, Susanne January 2009 (has links)
No description available.
13

Är det lönt att yttra sig över bygglov? : Studie av effekterna från Sundsvalls miljökontors remissvar i bygglovsärenden.

Hamrin, Åsa January 2008 (has links)
Detta examensarbete skrivs på uppdrag av miljökontoret i Sundsvalls kommun. Miljökontoret vill veta om och hur deras yttranden i bygglovsärenden ger avtryck i bygglovs- och byggprocessen, vart i processen de har störst chans att påverka, och hur de kan förbättra sina remissvar i bygglovsärenden. Tolv ärendens bygglovsremisser har granskats. Elva av de tolv remisserna är ärenden gällande fritids- och enbostadshus, det tolfte ärendet gäller en byggnad i skyddsvärd natur. Bakgrundsfaktan till denna rapport har inhämtats från SFS 1986:223 Förvaltningslag och SFS 1987:10 Plan och bygglag samt från två rapporter från Boverket. En intervju med en byggnadsinspektör har genomförts. I denna rapport redovisas vad en remiss är och några begrepp angående bygglovsprocessen och byggprocessen förklaras. Remissgången mellan stadsbyggnadskontoret och miljökontoret i Sundsvalls kommun redovisas och även hur miljökontorets remissvar senare hanteras av stadsbyggnadskontoret. Resultatet har visat att miljökontorets remissvar kan förbättras genom att de förkortas dem och att miljökontorets avtryck i processen finns i form av att byggherrarna läser och tar fasta på det mesta i miljökontorets yttranden. Resultatet har också visat att miljökontoret har störst chans att påverka bygglovs- och byggprocessen genom att begära att något lyfts fram vid byggsamrådet.
14

Svenska miljöteknikföretag i Kina : En studie om företags internationalisering på avlägsna marknader

Carlbrant, Thérése, Ellfors, Stephanie January 2012 (has links)
Sammanfattning Examensarbete i företagsekonomi, Ekonomihögskolan vid Linnéuniversitetet, Marknadsföring, 2012. Författare: Therése Carlbrant, Stephanie Ellfors Handledare: Anders Pehrsson Titel: Svenska miljöteknikföretag i Kina Bakgrund: Det satsas just nu mycket resurser på svensk miljöteknik eftersom dagens klimatomställningar är en stor utmaning och är en utav Regeringens prioriterade områden. På senare år har exporten av miljöteknik ökat men i förhållande till den totala andelen varuexport är den fortfarande låg. En av Sveriges största mottagarland är Kina. Kinas miljöproblem förväntas bli värre för varje år och landets ledare har utvecklat en viss insikt på senare år i den växande miljöproblematiken men det finns mycket kvar att arbeta med. Regeringen har tagit fram åtgärder och strategier för att främja svensk miljöteknik bland annat är Kina ett prioriterat land. Med hänsyn till detta finns det ett behov av att studera vilka faktorer som bidrar till export och etablering på utländska marknader och vilka faktorer som påverkar företagen i deras utlandsetableringar. Syfte: Syftet med denna studie är att öka förståelsen för företags internationalisering på avlägsna marknader. Problemformulering: Denna studie består av en problemformulering och är följande; Hur påverkar externa faktorer företags etableringsformer på kulturellt och geografiskt avlägsna marknader? Metod: Det empiriska underlaget består av kvalitativa studier baserade på fyra semistrukturerade intervjuer med personal från Absolent AB, Envac AB, ITT Water & Wastewater AB samt Exportrådet. Slutsatser: Våra studieresultat baserade på tre fallstudier visar på samband mellan host-country factors i form av kulturella skillnader och marknadsattraktivitet och val av etableringsform. Resultaten visar också på samband mellan host-country factors och inträdesbarriärer. De senare påverkar dock inte valet av etableringsform. Vi har även studerat påverkan av home-country factors på val av etableringsform men resultaten visar inte på ett tydligt samband. De studerade företagen har med anledning av dessa faktorer valt att etablera helägda dotterbolag.
15

Provtagning och analys av totalkväve, fosfor och BOD7 på inkommande avloppsvatten till Guldfågeln AB:s reningsverk

Hagberg, Anna January 2009 (has links)
Det huvudsakliga syftet med detta arbete var att undersöka innehållet av totalkväve, fosfor och BOD7 på inkommande avloppsvatten till Guldfågeln AB:s reningsverk. Guldfågeln AB har ett tillstånd enligt miljöskyddslagen för verksamhet vid fjäderfäslakteri från 1999. De har ett eget reningsverk där processvattnet renas genom fällning och flockning. Därefter går avloppsvattnet vidare till Mörbylånga kommunala avloppsreningsverk (KARV) där det renas ytterligare innan det når recipienten Kalmarsund. Guldfågeln har haft problem med förhöjda värden av kväve och BOD7 i sitt avloppsvatten som når KARV. Genom att ta prover på avloppsvattnet under ett dygn undersöktes förändringarna under processdygnet. Provtagningen utfördes med en programmerbar provtagare och delades upp på två olika processdygn. Analyserna av provtagningen visade att halterna av de undersökta parametrarna varierade under dygnet. Troligen beror detta på vilka processer som är igång och hur mycket material som når det interna reningsverket. Guldfågeln AB har justerat och genomfört åtgärder på sitt interna avloppsreningsverk. Detta arbetes slutsats är att Guldfågelns viktigaste åtgärd utöver de redan genomförda är att försöka minimera ingående partiklar så att så lite som möjligt hamnar i avloppsvattnet.
16

Suspended solids and metals in highway runoff : implications for treatment systems

Hallberg, Magnus January 2006 (has links)
<p>It is known that traffic is a source of pollutants and that pollutant loads increase with elevated traffic densities. Studies executed in Stockholm, Sweden advocate that highway runoff from roads with an annual average daily traffic (AADT) exceeding 30,000 vehicles need treatment before discharge to the receiving water. It is common knowledge that sedimentation is the most expedient method for stormwater treatment. However, sedimentation units are area demanding and in highly urbanised watersheds the land use is often restricted. Studies have implied the occurrence of first flush, i.e. an initially higher pollutant load in the beginning of the runoff event, in highway watersheds. With an emphasized first flush it would be possible to treat only a part of the total runoff volume reducing the area needed for a sedimentation basin. In general two methods are used to design stormwater treatment ponds. One method is based on the reduced catchment area and pond surface and the other is based on an average runoff volume and a permanent pond volume. The methods are relaying on data from routine monitoring of various treatment systems and suggest removal efficiencies for pollutants. Applying general removal efficiencies for design it can be intricate to estimate an outlet concentration when the specific removal efficiency may be dependent on the initial concentration of the pollutant. Consequently, knowledge of the removal efficiencies dependence on initial concentration would be helpful to optimise stormwater treatment systems. This research has studied runoff from highly trafficated watersheds. The aim has been to evaluate the mass transport, stormwater quality and sedimentation behaviour and their implications for stormwater treatment. The study sites, Eugenia and Fredhäll, are located along the six-lane highway E4 through Stockholm that has an AADT load of 120,000 vehicles and a speed limit of 70 km/h. In lack of a unified definition of first flush the mass transport was studied using the EU directive 1991/271/EEC discharge demand for TSS of 60 mg/l. It was found that for the majority of the runoff events during winter the event mean concentration exceeded 60 mg/l suggesting that the complete runoff volume should be captured during winter. The dissolved concentration of metals showed significant variations between winter and summer, as did the concentration in the particulate matter (mg/kg). It was possible to correlate total metal concentration to total suspended solids with good correlation (r2 >0.90) for the majority of studied metals in winter and summer. The findings would imply that a successful treatment of the studied metal pollutants could be carried out by sedimentation. However, depending on discharge criteria, the elevated levels of dissolved matter, especially during winter, have to be considered with regards to the selection of the appropriate water treatment process. The sedimentation process could be described by a logarithmical function and initial turbidity. Good correlation (r2 >0.90) was indicated between turbidity and TSS. The sedimentation process of the studied highway runoff varied significantly (p<0.05) when elevated levels of NaCl could be found in the runoff. A significant difference (p<0.05) was shown for turbidity and TSS between summer and winter, which was assumed to be related to the use of studded tires. This study implies that the entire runoff volume must be treated and that the use of first flush as a design criterion is less applicable for the winter period. The study implies good correlation between total metal concentration and TSS. In addition the indicated correlation between turbidity and TSS would point to the possibility to use turbidity as a surrogate measurement for TSS and the studied metals. Moreover, the possibility to describe the sedimentation process by the initial concentration of turbidity would infer the utilisation of turbidity as a tool for process control for stormwater treatment systems. In addition, the novel results for the dependence on the sedimentation process could be incorporated in existing models for design of stormwater treatment systems in similar watersheds.</p>
17

Öppna spisar : metod som förhindrar öppna spisar att ryka in

Södergren, David January 2007 (has links)
<p>The primary purpose of this thesis is to account for a new method of limiting the risk of smoke leaking out from the open fireplace into the room. The improved functionality is obtained by adding a turnplate to the open fireplace mounted horizontally inside the lower edge at the hood of the open fire. The streams of smoke and air, which are cold of the contact with the cool surfaces in the stove, have a tendency to fall down along the inside of the hood and continue out into the room. The stream is stopped and redirected back up into the chimney by the turnplate. The development of the method is based on measuring of temperatures and air flows in a monitored fireplace. Tests have been carried out partially in a test fireplace in full scale and partially in a model of the test fireplace at the scale 1:2. The model fireplace is made in glass which makes it possible to study and photograph the streams of smoke inside of the fireplace and oil fog has been used for the demonstration. Temperatures on surfaces and gases in the fireplace have been measured during different periods of time. These measurements have shown that the greatest risk for backwards floating air currents occurs directly after having lit the fire and during some hour after that. It is during this time the temperatures in the fireplace will rise. Measurements and also film-recordings have therefore been concentrated to these periods of time. The heat gain from the fire has been measured in connection to the tests. The distribution of the heat through radiation and convection based on the temperature measurements is shown.</p>
18

Artificial neural networks : applications in morphometric and landscape features analysis

Ehsani, Amir Houshang January 2007 (has links)
<p>IIn this thesis a semi-automatic method is developed to analyze morphometric features and landscape elements based on Self Organizing Map (SOM) as a unsupervised Artificial Neural Network algorithm. Analysis and parameterization of topography into simple and homogenous land elements (landform) can play an important role as basic information in planning processes and environmental modeling. Landforms and land cover are the main components of landscapes. Landscapes are dynamic systems that involve interrelation between physical characteristics (such as landform, soil) and anthropogenic processes (such as land use).</p><p>In morphometry (as general term of geomorphometry) - the qualitative and quantitative measurement of topography - morphometric parameters are calculated such as profile curvature and longitudinal curvature. They are then used in morphometric analysis to identify morphometric features like plane, channel, ridge, peak or pit.</p><p>In February 2000 the Shuttle Radar Topography Mission (SRTM), collected data over 80% of the Earth's land surface, to derive a consistent digital elevation model (DEM) for allland areas between 60 degrees N and 56 degrees S latitude. This DEM with about 90 m grid spacing was used to generate morphometric parameters of first order (slope) and second order (minimum curvature, maximum curvatures and cross-sectional curvature) by fitting a bivariate quadratic surface. These surface curvatures are strongly related to landform features and geomorphological processes.</p><p>The thesis starts with an overall introduction and literature review. Then two methods for morphometric analysis are compared: morphometric parameterization and feature extraction proposed by Wood (1996a), calculated with Geographic Information Systems (GIS) software and our method implemented with Self Organizing Map (SOM) as an nsupervised artificial neural networks paradigm.</p><p>Finally in our method for landscape element analysis morphometric parameters and remotely sensed spectral data are combined. The emphasis is on morphologically homogeneous landscape elements characterized by similar slope and curvature conditions. SOM is used to reduce large multidimensional data sets to one output layer consisting of 20 map units. These map units are interpreted in terms of morphometric features, slope and land cover to identify and characterize landscape elements or geoecological units</p><p>Both studies have demonstrated valuable methods for extraction of land information that can be used in geomorphologic applications and geoecosystem modeling. These methods allow important savings in field work and can be used as alternative to labor intensive manual methods. But results may depend on scale and quality of the DEM and the topographic situation; caution should be used in interpretation. Evaluation of these methods in other areas with different morphometric conditions and with multi-scale DEM remains to be done.</p>
19

Diffusion of innovative domestic heating systems and multi-storey wood-framed buildings in Sweden

Mahapatra, Krushna January 2007 (has links)
The diffusion of innovations that promote sustainable use of forest resources and energy efficiency is important for reducing greenhouse gas emission and dependency on oil. In this thesis the ‘systems of innovation’ (SI) The SI analyses showed that several sources of path dependency, resulting from the establishment and growth of the concrete-based construction system over the past 100 years, hinder the expansion of a wood-based multi-storey The adopter-centric approach included household questionnaire surveys: one covering the whole of Sweden in 2004 involving 1500 randomly selected homeowners with any type of heating system, and another in the city of Östersund in The expansion of district heating networks in the detached home sector, particularly those homes with resistance heaters, is often considered difficult. However, results showed that, in Östersund, the government investment
20

Water hyacinth - Effects on sustainable Devolopment : A minor field study about water hyacinth in Lake Victoria in Kisumu, Kenya

Rahman, Sunni January 2008 (has links)
Abstract The aim of the study was to do a minor field study in Kisumu, Kenya. My thesis in Ecological Economics C, 10p and the purpose was to explain the association between water hyacinth and sustainable development. What are the main effects on environments, ecological and social effects in Kisumu in Kenya? This paper will address environmental, economical and social effects related to the water hyacinth. I have chosen the qualitative method because I want to asses general impression and understand different processes and social connections. Interviews are made which aims to give a deeper focus by letting the interviewed person describe and openly answer the questions. The study is conducted as a combination of literature reviews, qualitative interviews with parties or people who are involved and other organisations in Kenya and from observations. The theoretical approach was Sustainable devolopment, control of social, economical and ecological perspective on regional development. Sustainable development include social, ecological and economics, all three are depended of each other to make progress. From a social point of view the plants give people a society and provide work and knowledge on how to recycle the weed. Economically, it is a disaster but the good opportunities come from recycling even if it contains a lot of water. Eutrofication and blocking of sunlight are the most ecological effects caused by water hyacinth. If people are prepared to vote for honest representative no bribes will take place, these kind of statement are important and its time that people takes responsibility for their act, mainly environmental responsibility which are important for our common future. It should be expensive to destroy the nature, on the other side you do not know the value according to Dryzek. A suggested idea is to turn this into a tourist attraction which hopefully will become popular. To remove the weed by the biological method is the best controlled, cheapest and it is the most sustainable method of weevil’s which eats the leaves of the plants. Contact: Sunni Rahman Telephone: +4670-768 52 54 E-mail: srn01001@student.mdh.se

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