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983 Uppsatser om Heat transfer - Sida 28 av 66
Det självförsörjande passivhuset
The housing sector uses 40 % of the energy in Sweden and half of the electricity usage. Theuse of energy is the main reason to the increasing rate of carbon dioxide in the atmosphere.This is the main motive but also a wish of higher safety, that is a higher rate of selfsufficientenergy production in Sweden, we want to decrease the need of using fossil fuel. Now whenthe energy price rise, the interest in energy issues increase and more people discuss thepossibility of reducing the usage of fossil fuel. A change to renewable energy such as sun,wind and water is the only solution where we can get a sustainable development.One way to contribute to a better use of energy is to build in the principle of passive house.The house is being built with a thick and tight insulation. If you use a heat-exchanger withhigh degree of efficiency and a final heating battery on the ventilation system, the heat fromlamps, devices and the ones living in the house should be enough to fulfil the criteria ofliving.
Kunden i centrum : att nyttja potentialen i den interna förmedlingen av kunder
LRF Konsult is a big consulting-firm with offices located all over Sweden. The corporation offers a wide range of services and a lot of the customers are small businesses active within the green sector. An analysis of the corporation made in 2006 showed that one of LRF Konsults weaknesses is that many customers are unaware of the wide range of services that LRF Konsult offers. The internal communication is believed to play a big role in marketing these services. Therefor, the objective of this thesis has been to investigate why the transfer of customers between accounting consultants and business advisors is not greater and how this can be improved.
Studie av verkningsgrad potentialen för ett vatten baserat Waste Heat Recovery system med kolvexpander
SammanfattningEn ånganna monterades i EGR (Exhaust Gas Recirculation) slingan på en 12,7 liters Scania Euro V motor (DC1306). En modell som beskriver Rankine cykel togs fram med vatten som köldmedium i simuleringsverktyget GT-Power. Ångpannan i GT-power modellen kalibrerades m.h.a experimentell data.Simuleringarna visade att det optimala ångtrycket, det trycket där högst effekt kan erhållas från expandern, är beroende av EGR temperaturen. Det innebär att ju högre EGR inloppstemperatur desto högre optimalt ångtryck. EGR temperaturen i punkt 2 i ESC cykeln är 514? C för denna motor, vilket resulterar i ett optimalt tryck på 120 bar enligt simuleringen.
Framtidens energieffektiva flerbostadshus
The housing sector of today represents for almost 40% of the energy consumption, an energy consumption of which the major part consists of non-renewable energy sources. This is not sustainable and utilization of new energy-efficient technologies in buildings can be a step in the right direction, towards a sustainable energy society.This report has been made on behalf of and in cooperation with Älvstranden Utveckling AB in Gothenburg to examine how future energy-efficient technologies can affect the energy demand in energy-efficient multi-dwelling buildings.The report is based on Älvstrandens passive house, Hamnhuset, a house whose energy consumption is far below the BBR's requirements. The report looks at the opportunities for improvement within windows, insulation, solar energy technologies, as well as white goods. Computer simulations are then made to apply the selected technologies into a reference building. Technologies are selected from an energy efficient perspective and no account has been taken of other aspects such as the economy.
Kommunikation mellan två medium
The aim of this project is to find a concept solution for a wireless transmitting system, installed to transmit data from a hydrophone of the ocean floor down by a wave power generator to the office on shore. The project is a literature review in which previous observations and tests are analyzed and put together to find a solution. The result was a comprehensive solution that includes an acoustic modem to transfer captured information from the bottom to the surface, wirelessly through the water. The information is then sent fron the surface on radio waves through the GSM network to the office on land. Between under and over water there are components to convert information between acoustic waves and radio waves, but also various types of modulation, such as amplitude and frequency modulation is required..
Methane emission from nitrate-treated tannin rich feed for cattle in Vietnam
In developing countries such as Vietnam the population consumes more animal products for example milk and meat than before which requires greater livestock production. Ruminants contributes to more methane emission which creates a dilemma between food production and its environmental impact. By feeding ruminants with nutritive crops which humans can not assimilate the animal performance will increase in terms of better growth and milk production without inpinging on food that can be consumed directly by humans. Increasing animal performance reduces methane emission in terms of amount of methane in kg-1 milk and meat which today is much greater in developing countries than developed countries. The aim of the study was to investigate tropical tannin-rich legumes for their potential as a feed supplement for ruminants made in vitro.
Problemlösning på väg mot lean production: en studie på
Sandvik Band
Detta examensarbete kom till eftersom Sandvik Band ville ha en utredning till stånd gällande sin problemlösning. Detta då Band hade skäl att anta att problemlösningen i många fall skedde i form av ?brandsläckning? med alltför begränsad uppföljning. Syftet med examensarbetet blev att kartlägga hur problem i produktionen upptäcks, löses, följs upp och dokumenteras. Förslag på hur eventuella fel och brister i denna process skulle kunna elimineras skulle också tas fram.
Regressionsmodellering av dynamiska råemissioner från statiska mätningar
By using steady-state measurements for predicting emissions under a dynamic drive cycle wouldsave a lot of time and money for the exhaust aftertreatment specialists at Volvo cars. The idea forthis thesis has been to investigate if statistical regression models can be used with good accuracy.Questions included are for example if common operating variables such as engine speed, air-fuelratio etc. is sufficient to predict engine-out emissions over the engine operating range with goodaccuracy. Focus was set on the modelling of warm engine, but also the more complex engineheat-up phase was investigated since it is a great contributor to total emissions. While NOxcouldnot be measured because of malfunctioning measurement equipment, only HC, CO andtemperature at inlet of first catalytic converter has been modelled.
Optimering av glödgningsparametrar för kromstål
At Sandvik Materials Technology, Argon gas is used as furnace atmosphere when heattreating hot rolled wire. Upon heating chromium steel wire, a rich oxidelayer forms on the wire surface. The abstract of this masters thesis is to enhance the understanding of the constitution of the oxidelayers and the influence of the furnace atmosphere. This will be achieved by performing a number of annealing experiments on laboratory level. Also, the aim is to understand the chemical reactions and physical mecanisms controlling the pickling process.
Social hållberhet genom medborgardialoger : exemplet Husby
Understensho?jden is Stockholm's largest eco-village which was built in the early 1990s with the vision of enabling ecological living for people. However the ecovillage is no longer considered as environmentally friendly because of its relatively high energy consumption, and non-updated energy system. The purpose of this study is therefore to investigate how Understensho?jden should reduce their energy consumption and upgrade its energy system by using Blower-Door, IR-camera and Design Builder.
Renovering av flerfamiljsbostäder inom miljonprogrammet ur ett energi- och lönsamhetsperspektiv
Miljonprogram is a Swedish building program from 1964 to 1975. During that time about a million homes were constructed. Now, almost 50 years later, they are in desperate need of renovation. In order to fulfil the Swedish environmental objective to decrease energy consumption 50 per cent until 2050, considerable housing stock built under the Miljonprogram has to be renovated.Focus in this thesis is on the building services and theirs profitability that can decrease energy consumption in households build during the Miljonprogram. Building construction is not considered in this report.
Filter och kapsling för IR-givare
This paper describes the work done trying to diminish the noise present in the signal from an IR-detector. The project was aiming towards two different kinds of applications; heat protection and presence detection. The hypothesis was that the signal-noise ratio would decrease if a filter and a proper installation were used for the detector. Some experiments were executed to determine what kind of filter were the most suitable for each application and how these could be installed. After executing the experiments and evaluate the results we recommend to use a specific filter for each application.
Beskrivning och analys av superovuleringsresultat och andra fertilitetsregistreringar vid Nötcenter Viken :
Recording and analyses of superovulation results and fertility records at the nucleus herd Viken
The development of different reproductive technologies aim at increasing the number of progeny per individual parent, and in that improving the possibility of genetic progress. One technique, embryo transfer, have facilitated genetic dissemination and shortened the generation interval also in females.
Nötcenter Viken is a company that run embryo collection and embryo transfer in the breeds Swedish Red and Swedish Holstein. It is located outside Falköping. Information is continuously gathered about cows tested at the nucleus herd.
Elevers föreställningar om liv : undersökning av elevers lärande ur ett socialkonstruktivistiskt perspektiv
The purpose with this study was to analyse students' conception of living things, and to establish how a social constructivist learning situation affect their conceptions. The method consisted of questionnaires, followed by group discussions and a final survey. The main result was that students have everyday conceptions about scientific phenomena that are reinforced by the social interaction. Some students were positively influenced by the interaction with their peers, where non-scientific conceptions were replaced by conceptions of a scientific nature. Furthermore, the cultural artifacts are of very good means, but the study showed a strong need for a knowledgeable person, e.g.a teacher, to guide students in the right direction during the discussions.
Internprissättningsdokumentation : Bör de svenska internprissättningsdokumentationsreglerna med hänsyn till BEPS åtgärdspunkt 13 revideras, och i så fall, vilka generella aspekter bör lagstiftaren ta hänsyn till vid utformandet av svenska framtida dokumen
2007 infördes regler om dokumentationsskyldighet i Sverige. Reglerna baserades på OECDs riktlinjer för internprissättningsdokumentationskrav. I slutet av september 2014 publicerade OECD BEPS-rapporten ?Guidance on Transfer Pricing Documentation and Country-by-Country Reporting? vilken innehåller omfattande förslag på hur OECDs nuvarande internprissättningsdokumentationsregler bör revideras. Frågan blir därmed om, och i så fall hur, kommande svenska internprissättningsdokumentationsregler bör utformas?Det finns idag betydande skillnader mellan nuvarande svenska bestämmelser och OECDs kommande ändringar.