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2547 Uppsatser om Renewable energy sources - Sida 53 av 170
Att lära med webquest. En fallstudie om studenters erfarenheter av Webquest för barnmorskor vid Karolinska Institutets Universitetsbibliotek.
The main purpose of this Master Thesis is to describe students experiences of learning with Webquest för barnmorskor (Webquest for midwifes) at the University Library of Karolinska Institutet (KI), Stockholm. To investigate the possibilities of acquiring information literacy in higher education with the webquest model a qualitative case study is carried out, based on five interviews with students. The students? perceptions of the webquest course and their ideas on information seeking and information literacy are being analyzed in relation to a framework of learning theory and information literacy expressed by documents and librarians of KI. A descriptive presentation is structured from the main themes that emerged in analysis within the frames of my research questions.
Småskalig elproduktion i Arvika
Arvika Fjärrvärme AB, a district heating company from Arvika, today cover 74 % of their total energy production with biofuel wich runs a 16 MW bioler giving process water at saturated liquid state.In recent years Vaporel AB has introduced a new tecnique that gives an external generation of steam after boilers. The concept is built on an adiabatic pressure drop of the saturated liquid in a so called Flashbox which makes a small part of the liquid to evaporate. The generated steam is lead into a turbine where electricity is in a conventional manner.The purpose with this rapport was to do a basic study for the specific system at Arvika where it?s possible to see the potential production of electricity that follows an installation of a flasbox.The final goal was to introduce an economic analysis of a flashox installation at given conditions.To reach our goals we have created a model in Excel where we used the given conditions at Arvika Fjärrvärme to do our calculations. The model has been tested at three different states, of process water returning to potboiler, to be able to decide the optimal operation for the system at present.The studies have resulted in a pressure of the processwater at 14,5 bar (at) and a pressuredrop to 9,5 bar (at) in the flashbox.
Energieffektivisering på Vista
Sweden has distinct seasons with cold winter and temperatures down to minus 25 ?C andpleasant summers with temperatures above 20 ?C. During spring and autumn there could becomechallenges with precipitation. The diverse climate in Sweden affects many homeowners. For thepeople living in leisure boats and permanent housing boats the seasonal changes are clearlyimpacting their economy and the indoor climate.
Utvärdering av en väggkonstruktion utan PE-folie : Med en undersökning av hårdvaxolja som diffusions-/konvektionsspärr
District heating covers around 80 % of the heating demand in apartment buildings and 10 % in single-family homes in Sweden. In the year 2010 the total input of energy to the Swedish district heating grids was about 70 TWh, which corresponds to 11 % of the total energy input to the whole energy system in the country. Through the combined production of heat and power the CHP-plants often reaches an efficiency of 90 % from energy in the fuel to produced heat and power. In order to keep the efficiency high it is important for the owners of the plant to have good knowledge about the plants performance at different operation points. Strängnäs Energi AB initiated this diploma work together with FVB Sverige ab in order to come up with a program for short term planning of the production of heat and power at the company´s CHP-plant.The work consists of three main parts.
Ersättning av fossilt bränsle i värmeproduktion: Pulverbrännare till befintliga oljepannor
Vi står inför en förändring, att minska vårt beroende av fossil energi till förmån för en ökad användning av förnybar energi. Incitament i form av ökade punktskatter på fossilt bränsle påskyndar omställningen för företag till förnybar energi och- eller energieffektivisering av sin produktion. Konsekvensen blir en successivt fördyrad kostnad för produktion av fjärrvärme med eldningsolja till tillverkningsindustrin. Punktskatt på eldningsolja stiger med 41 procent, från 2010 till 2015 för företagen. Att konvertera befintliga oljepannor med träpulverbrännare är en lösning för att hålla produktionskostnaden nere och behålla sin konkurrenskraft.
Svenskars färd mot Mörkrets hjärta : Om svenska militärer som sökte tjänst i Kongostatens kolonialarmé 1895-1906
The aim of this paper is to map and analyze what role Swede's played in King Leopold II's colony in the former Congo Free State. Letters and messages that arrived at the Congo Consulate in Sweden between 1895 and 1906 have been used as the paper's primary sources. Application letters from 32 different Swedes, seeking to join the Congo Free State Army, to the General Consul of the Congo Consulate, Hans Hugold von Schwerin, have been used as primary sources, and constitute the basis of the paper's analysis. The letters arrived at the Congo Consulate in Sweden between 1895 and 1906. The applicants were all men of different social classes, and were between the ages of 20 and 30 years old. Their chief reasons for applying were primarily for own financial gain or because they did not get a chance to serve in the Swedish army.
Representativa testnät försvenska eldistributionsnät
This project was started within the Market-Design programme of Elforsk, with the aim of developing representative test systems of Swedish distribution networks. Using such test systems as a basis for reliability and customer interruption cost calculations makes it feasible to analyse the network tariff regulation of Swedish power istribution companies. In particular, it enables studies of the incentives for companies to invest in system reliability. Until now, the available test systems are either not representative of Swedish conditions, or too small in scale and limited in function.Within this project we have created two test systems. In order to represent the diversity of actual Swedish distribution networks, we have created one test system for urban environments and another for rural environments.
Rätt gåva för rätt tillfälle
This master thesis is a study of the Swedish hydropower capacity to balance wind power. The Swedish government has decided that it should be possible to produce 30 TWh from wind power in the year 2020. The Swedish municipalities have to have plans for wind power plants with total yearly generation of 30 TWh. Wind power is an variable energy source that needs to be balanced by other energy sources. In Sweden the Swedish hydropower can be used for balancing a large scale introduction of wind power.
Elevers tillämpning av källkritik på Internet
This paper, called Pupils' practice of source criticism on the Internet, is investigating pupils? use of source criticism. The main research question was: how much knowledge pupils from an upper secondary class have about the use of source criticism, regarding examining data from the Internet intended for assignments. Furthermore, developing a suitable method to investigate this was included. The main research question led to further sub questions that aimed to answer to what extent pupils consider source critique criteria as sender, aim, up-to-dateness, credibility and dependence.The study has been conducted by using mixed methods, both qualitative and quantitative methods.
Solvärme för en skola i Lerum. Studier av olika systemalternativ.
Two elementary schools are now being built in Gråbo (in the municipality of Lerum),Röselidsskolan and Ljungviksskolan, which are both designed with solar thermalcollectors for the schools domestic water heating. During the summer while thelargest amount of solar heat can be generated, the activity hence the domestic wateruse in the schools are heavily reduced. Both schools are connected to the local districtheating system which makes it possible to use the solar collectors to deliver heat tothe district heating.The purpose of this thesis is to evaluate the two systems mentioned above and todetermine which system is more suitable to apply on a school. The building whichconditions were used for this evaluation is Röselidsskolan.A solar heating plant of each system type was dimensioned from the expected andknown conditions of the building. The purpose with the dimensioning was to makethe solar plants replace the ordinary energy source as much as possible.
...de bultades till bättring : till frågan om Sveriges kristnande
The written sources concerning the process of christianization in Sweden has for a long time been limited to two main texts, Rimberts vita of St. Ansgarius and Adam of Bremen´s History of the bishops of Hamburg. This is due to a rigid source criticism in the beginning of the 20th century, which put other material ? in particular the norse sagas ? out of consideration. The last twenty years however, new questions have been raised concerning the christianization, partly because of new archaeological findings, new interpretations of the significance of runic stones and the recent debate about the formation of the Swedish medieval kingdom.
Illiterata invandrares informationspraktiker
The subject of this two year Master's thesis in Library and Information Science is the information practices of illiterate immigrants in everyday life. The purpose is to examine how immigrants seek, identify, understand and value information sources and information, and how the practices have changed with their arrival in Sweden. It furthermore focuses on the barriers that illiterate immigrants meet in accessing and understanding information. It moreover investigates the strategies they use to overcome them.For this purpose twelve qualitative research interviews were carried out, with illiterate immigrants as well as with service providers. The theoretical concepts of the essay is information practices, which means that the information process is within a context, and information poverty, that people in different context do not have adequate and equal access to information and information sources.Using McKenzie's model of information practices, the essay concludes that illiterate immigrants are active in their information process, especially when they interact with information.
Metoder att förhindra nedisning av vindkraftverksblad
ABSTRACTMany wind turbines have problems with icing and there is still no effective method to de-ice without stoppage of production and power loss. Here I therefore consider other methods than those available today, and particularly, I consider how these methods could be applied to wind turbines of the company Oxel. A surface where the water droplets do not attach might be the basis for a useful method. If no water attaches, no ice could form. To accomplish this a hydrophobic surface is nessesary, for example wax.
Termisk Vattenpump
This degree project aims at developing a concept for how to use solar energy to pump up water. The target audience is people living in areas where the functioning of the electricity and water network is absent. In these areas, the hand-powered water pump is the most common technology. The degree project's goal is to find an economically viable alternative to the time consuming hand-powered water pumps. The power comes from solar energy.
Kan perfluorerade ämnen i kläder bidra till förhöjda halter i reningsverk?
Perfluorinated substances (PF) are environmental pollutants that are used to coat fibres of so called ?all weather clothes? to make them water resistant. PF are effectively spread through water. Waste water treatment plants (WWTPs) are a pollutant source of these substances. PF are poisonous to different kinds of organisms, and supposedly also to human beings, if concentrations are sufficiently high.Perfluorinated substances have been investigated at three waste water treatment plants in Stockholm during the 2000?s.