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983 Uppsatser om Heat transfer - Sida 27 av 66
Effektiv lagerstyrning genom tillförlitlig prognostisering : Effective inventory control through reliable forecasting
This study was done regarding whether sealing or ventilation is the best solution to prevent moisture on cold attics. The authors of this report addressed the problem with moisture in attics when they started their cooperation with Peab.The methods included interviews with people, database research, and calculations of a project in Akersberga north of Stockholm. The conclusion is based on interviews and other information as they are analyzed in relation to the house of reference. The focus of this report is on problems with moisture in the attics known as cold attics.The background of the problem with moisture is that today?s slabs are usually insulated to save energy and that the attics nearly gives the climate as the outdoor climate.
Framtida användningsområden för materialadderande tillverkning : En studie i hur materialadderande tillverkning kan användas i rymden
In this paper we have studied possible future uses for Additive Manufacturing (commonly referred to as 3D-printing) in Space. More specifically we have sought to establish how Additive Manufacturing can be used to construct structures on the Moon. Our studies have shown that Additive Manufacturing has great potential for establishing colonies on not only the Moon, but perhaps even further away from our home planet. With Contour Crafting-technology in combination with ISRU (In Situ Resource Utilization) we could, with material already present in the sediment layers of the Moon, construct advanced structures without having to transfer any extra material from Earth. This would lower the costs of establishing a colony on the Moon to such extents that it could actually be fiscally possible..
Nollenergihus i Borlänge : Är det möjligt med biomassa, solenergi och vindkraft?
This report is of technical character and treats how to plan a small building in Borlänge, Sweden.The technical components that have been treated in the report are the construction, foundation,installations and thermic abilities of the house. In addition to planning this house the report alsocontains a part that deepens in net zero energy buildings. The purpose of the report is toinvestigate if the house in Borlänge can be constructed to meet net zero energy buildingdemands.Energy efficient houses such as passive- and net zero energy houses are showing more frequenton the market in Sweden. Ongoing climate changes and growing consciousness about theenvironment in society have contributed to that the environment is a well discussed topic. Toconsume small amounts of energy and at the same time produce local energy is thereforesomething that lies in the future and future houses.
Energibalansen för ett nytt flerbostadshus i Mellansverige : Beräkningar intervjuer och analys av energikraven i Boverkets Byggregler
Abstract This degree project comprises 30 credits, i.e. 20 weeks of work. The work mainly deals with the energy balance for a multi-family house in Västerås and the requirements for energy conservation in the Swedish building code, BBR. Calculations of the energy balance are supplemented by a number of interviews. Energy conservation in general has become more important in recent years and the subject is in line with increased public awareness. This importance and attention is explained by environmental problems in general and global warming in particular, but also by rising energy prices.
Tätning eller ventilering mot fukt på kalla vindsutrymmen
This study was done regarding whether sealing or ventilation is the best solution to prevent moisture on cold attics. The authors of this report addressed the problem with moisture in attics when they started their cooperation with Peab.The methods included interviews with people, database research, and calculations of a project in Akersberga north of Stockholm. The conclusion is based on interviews and other information as they are analyzed in relation to the house of reference. The focus of this report is on problems with moisture in the attics known as cold attics.The background of the problem with moisture is that today?s slabs are usually insulated to save energy and that the attics nearly gives the climate as the outdoor climate.
ELCERTIFIKAT - En diskussion kring de svenska elcertifikatens rättsliga natur, ekonomiska värde samt möjlighet att ta i anspråk vid en utmätning -
1st of may 2003, a new energy system based on electricity certificates, was initiated in Sweden. The purpose with this system, is to stimulate an enlargement of energy production from renewable sources. The electricity system, ist built on that the producers of energy from renewable sources confer a electricity certificate from the government for every produced MW energy from renewable sources. The electricity certificate is supposed to be turned over and with that generate reciepts to the producers. Furthermore there is an obligation for the energyusers und energysuppliers, that means that the users and the suppliers every year the 1st of april got to have electricity certificates in proportion to their energy consumption during previous year.
Systemlösningar för plus- eller passivhus : En studie med syftet att lösa energibehovet för ett specifikt hus.
The purpose of the house which is the basis of this report is to be able present itself on the market as a relatively cheap and at the same time a climate friendly choice. The house is supposed to be able to be built anywhere in Sweden and the rest of Scandinavia in a short period of time. This puts demand on what kind of heating system the house can have, since not all places have the geographic advantage of being able to use geothermal or district heating. Therefore the heating system choices will only include those that are not limited by their geographic location. The house will be built in modules which only require the groundwork to be done before the house can be erected. In this report "System solutions for plus or passive-housing" a comprehensive literature search has been conducted as well as a number of calculations.
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).
Vems islam och kristendom? : En undersökning av tre gymnasieläroböckers beskrivningar och rekontextualiseringar
The purpose of this paper has been to highlight how three different highschool textbooks portrays Christianity and Islam. The aim of the paper has been to higlight and pinpoint how the three different textbooks uses different angles and perspectives on recontextualization; which ergo in turn creates a different field of transferred knowledge from each individual textbook.The paper uses an applied model of Bernstein?s theory of recontexualization, and from it derives two analytical tools to process and make an analysis of the textbooks transferred knowledge. The first analytical methodical tool of Bernstein?s theory is positioning, which is used in the paper to highlight what the different textbooks value and evaluate different kinds of knowledge of Christianity and Islam.
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.
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.
Trådlös energiöverföring via elektromagnetisk induktion
This paper describes a method for wireless energy transfer via near-field electromagnetic inductionthat is inexpensive, simple and can be applied to almost any type of system, regardless of size andenergy demands.The method uses a primary unit consisting of an oscillator, amplifier and inductive coil thattransfers energy to a secondary unit consisting of a coil, rectifier and voltage regulator. Two typesof oscillators and several amplifier designs were realized and evaluated together with a multitudeof flat coils of both monofilar and bifilar type.The results show that it is important to use an oscillator whose frequency is dependent on theinductance of the connected transmission coil, such as the Colpitts oscillator. This is preferable toan oscillator with a preset frequency, such as a Schmitt-trigger oscillator..
E-handel i småföretag
E-commerce is a conception who many are taking about nowadays. E-commerce is associate with computer based business and it?s a new way to do business on. Users and system connect up to each other for effective mediate and transfer information. Within e-commerce there?s a lot of ways to do business on and it can for example be between a business and a another business (B2B) or between business and consumer (B2C).In this degree report have I reached if small business will invest on e-commerce and if they will, how.
Dekorering av dispenser för allmänna hygienutrymmen
SCA, Svenska Cellulosa Aktiebolaget, är verksamt inom produktion av personliga hygienprodukter, mjukpapper, förpackningar, tryckpapper och sågade trävaror. Inom segmentet mjukpapper för storförbrukare levererar SCA hygienlösningar under varumärket Tork i form av bland annat papper, tvål och tillhörande behållare, så kallade dispensrar. Företaget vill nu undersöka möjligheterna att dekorera dispensrar, det vill säga trycka ett motiv i form av en bild, en färg eller ett mönster på produkterna, på ett sätt som differentierar dem från konkurrenternas produkter och samtidigt stärker varumärket. Syftet med detta examensarbete har därför varit att med en systematisk designmetodik genomföra ett designprojekt för att utvärdera möjligheterna att dekorera dispensrar. Målet har varit att rekommendera dekortekniker som är lämpliga att använda och ta fram designförslag på hur en dekor skulle kunna se ut för att överensstämma med uppdragsgivarens budskap.Projektarbetet har systematiskt gått igenom produktutvecklingens olika faser.