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858 Uppsatser om Coefficient of heat transmission - Sida 26 av 58
Varför uppförs så få bostadsrätter med passivhusstandard i Sverige? : En fallstudie mellan ett passivhus- och en konventionell fastighet
Abstract Background: In 1997 the Kyoto Protocol was signed, it?s an international agreement which is aimed to reduce greenhouse gas emissions. Sweden's goal is to reduce energy using in buildings with 20 percent by 2020 and 50 percent by 2050. This is a comparison with levels from 1995 (Glad, 2006). For Sweden to be able to reach its goals, they need to construct more low-energy buildings (Åhman, Wahlström & Lundblad, 2010).
Kaffesump som substrat i biogasanläggningar eller som bränsle i fjärrvärmeverk : en studie av effekter på växthusgasutsläpp och kostnader
Each year, the coffee machines at Ericsson in Kista produce around 100 tons of ground coffee waste.The companies Coor Service Management, Löfbergs Lila and Selecta are all responsible for differentstages in the logistical chain in delivering coffee and, together with Ericsson, they want to increasetheir environmental benefit. The plan is to produce biogas through anaerobic digestion instead ofincinerating the coffee waste in a heating plant. The results are to be presented as different businesscases in which different biogas plants are compared with the reference case (heating plant),comparing costs and environmental impacts.There are two major environmental benefits from producing biogas; reduced carbon dioxideemissions from when fossile fule is replaced by carbon neutral biogas, and reduced emissions fromreturning digestate from the bio reactor to farmland instead of using industrial fertelizer.In order to determine the biogas potential in coffee waste, a couple of properties had to bedetermined in a laboratory. Properties such as the dry substance content, heating value, moisturecontent and ash content. The results show that 100 tons coffee waste could produce around 16 500Nm3 biogas which would contain 163 MWh.The biogas reactor and upgrade plant both need energy gas to function and uses around 14 MWh ofthe produced gas.
Laborationsmätning av vindtäthetens betydelse för en väggs U-värde
To fulfill the climate target that EU and the Swedish government have decided to apply, it becomes increasingly important that the energy efficiency of existing buildings and making new buildings energy efficient as possible. Of Sweden?s total energy consumption in 2011 was 40% used by residential and service. Of the 40% of the energy consumption was 60% used for heating and domestic hot water. A report from year 2012 shows that one reason why the heating volume is so great could be due to underestimating on the energy consumption for the heating in the planning of the building.
åååååÅÅÅÅÅ TEMPO!! : En studie kring studenter och dryckesvisor
The aim with this essay has been to see how students use drinking-songs and what function they have. I have also wanted to see how the traditions are carried on between the students. In order to do this, I have been observing three parties organised by three different student associations at Växjö University: Västkustens nation, Föreningarnas Festeri and Isterbandet. I have interviewed five people that have been attending the dinners. I have used Alan Merriam?s theory of use/function and made interpretations of his theory.
Optimering av sotningsfrekvens i biobränsleeldad CFB-panna : panna 5, Mälarenergi AB, Västerås
During the past 30 years the fuels for energy production in heating and power plants
have changed. Fossil fuels have decreased in usage whereas bio fuels in Sweden
have increased with 60% since the 1970's. Different fuels affects combustion and the
release of various substances and particles into the flue gas. This is caused by the
diverse components and chemical structures of fossil fuels and bio fuels. When the
flue gas leave the combustion chamber and enters the path to the chimney particles
in the gas are being transported out of the combustion chamber.
Konstruktion av patientsimulator för anestesimaskiner
A patient simulator for testing anaesthesia machines has been developed at Maquet Critical Care AB, to reduce costly and time-consuming experiments on animals. The device simulates human lungs regarding lung dynamics and volume, uptake of anaesthetic agents and the production of carbon dioxide, heat and moisture. Further demands on the simulator are durability and size; the device shall be compact enough to be moveable.The resulting simulator fulfils the requirements and enables better repeatability and ability to test extreme cases than experiments on animals do.Uptake of the anaesthetic agent is achieved in a active carbon filter and controlled by regulating the flow. The flow is created by a regenerative blower and controlled using a proportional valve. The uptake can be set by the user or by a simple uptake model modified to recursively handle changes in the concentration of anaesthetic agent.Carbon dioxide is fed into the system from a tank by a mass flow regulator.
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.
Hejoppa hejopp! : En musiketnologisk studie av musikrepertoar och dess tradering inom lajvkulturen
The aim of this essay is to study and show the contents of the music repertoire that is used in live action role plays in Sweden and study how this repertoire is spread between participants in the culture of live action role playing.Four informants have been chosen and interviewed, three men and one woman of different ages from different places in Sweden. They have all been practicing live action role playing for some years.Some of the conclusions that can be drawn from this study is that the participants of this hobby culture value music that feels old and contribute to the illusion of another world and time. The music repertoire of the live action role playing culture is filled with this music that gives the participants associations in line with the illusion. That is more important than the real age of the music. Another interesting conclusion is that the participants learn and spread the melodies verbally to each other and only the texts spread on the internet..
Varför svänger stenen? : En studie i curlingens komplexa tribosystem
The tribo system ice-curling stone was investigated in order to understand the mechanisms behind the stones' behavior on the ice sheet. The problem with non-identical stones should also be addressed.The stone curls, that is, its sliding path deviates from a straight line to the right for a clock-wise rotation and to the left for a anti-clock-wise rotation. Several mechanisms to explain this behavior have been proposed over the years but none has been successful.By carrying out experiments at the local curling rink and studying silicon castings of ice- and stone-surfaces with scanning electron microscopy and vertical scanning interferometry, it has been decided that the curl is not due to dry friction, ice-debris or the difference in friction on the left and right side of the stone. The side force comes from the fact that the friction is higher at the back of the stone than at the front.The contact between stone and ice is never completely dry, nor in the hydrodynamic lubrication regime. It is probably a combination of hydrodynamic lubrication and a contribution from mechanical scratching of the ice.
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.
Storage stability in a milk based UHT-beverage : effect of pH, carrageenan and storage time
The different characteristics of many food products, such as aroma and texture, changes during storage time and become undesirable. The reason is instabilities within the product which become prominent as the product ages. These changes in characteristics are quality losses caused by changes in the product?s intrinsic and extrinsic environment. The stability in UHT-milk and beverages similar to it have been studied in the past decades and a certain focus have been on age gelation which is a common
defect in these type of products.
TCP/IP i taktiska ad hoc-nät
TCP (Transmission Control Protocol) is a transport protocol designed for the wired Internet. In wireless networks packet losses occur more frequently due to the unreliability of the physical link. The main problem is that TCP treats all losses as congestion, which leads to a lower throughput. Ad hoc networks are multihop wireless networks of mobile nodes, where each node can allow other packets to pass through it. Topology changes often occur and may lead to packet losses and delays, which TCP misinterprets as congestion.
Effektivisering av urvalsprocesser vid analysering av björnspillning : Ett förslag till den svenska förvaltningen av brunbjörn Ursus arctos
The aim with this report is to formulate a strategic method to optimize selection processes of DNA-samples from a faeces inventory to identify as many individuals in as few analyzes as possible, and by that keep down the costs of brown bear management. Brown bear management in Sweden founds today on results from faeces inventory and is substantially led by the county administration boards. Data from the years of 2004 and 2009´s inventories in Västerbotten was used to test and evaluate different methods in selection processes of which faeces that should be sampled. Comparison were made between making selection by chance, by spatial distribution and by calculating variations in logistic regressions coefficient b, in other words bear density and probability in finding same individual in several faeces. We can show making selection by chance is the most uncertain method.
Elektromekanisk växel för tunga lyft : Konceptutveckling
The basis of the study lies with a newly patented gearbox by cardiologist and inventor Stig Lundbäck. Stig founded CorPower Ocean AB to further develop the gearbox to be used in a wave energy device. The purpose of this project is to develop a concept of a lifting system with CorPower Oceans gearbox that is more energy efficient than a hydraulic lifting system. The goal is to use technology from CorPower Oceans gearbox inversely to perform heavy lifting as an alternative to hydraulics. The project is limited to applying the gearbox and gear rack on a forklift with a lifting capacity of ten tons.The main tool in this project will be the product development process Systems Engineering where only the most relevant parts will be used to develop a concept.
Ökad flexibilitet i Anybus X-gateway med hjälp av Lua
HMS Networks AB develops, produces and sells communication technology for industrial automation. The product handles communication between a variety of protocols. The product treated in this project is an Anybus X-gateway Modbus-TCP Master/Client and this module is currently configured from a web-based interface. In doing so, the flexibility for handling protocols is limited to what the company chooses to add to the interface. Therefore the company had a request that the flexibility should be extended using a script language.