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858 Uppsatser om Coefficient of heat transmission - Sida 22 av 58
Myt och vetenskap om kastration av tik
This is a literature study in which I investigate if there are scientific studies that form the basis of the Swedish dog world views concerning the spaying of bitches. The positive impacts are said to be reduced problems with pseudopregnancy, reduced risk of pyometra, reduced risk of mammary and uterine tumors, an earlier cease of bone growth, a more active and happier dog and a bitch who is more tolerant of other dogs. The negative consequences are said to be urinary incontinence, increased aggressiveness, lower metabolism and the increased risk of obesity, a more lethargic individual and altered coat.There are studies indicating that spaying reduces behavioral problems associated with heat and pseudopregnancy. Assuming no ovary tissue persists after the procedure, and there is no progesterone production, the risk of pyometra decreases. Early spaying, before the first heat, reduces the risk of mammary tumors.
Verktyg för värdering av miljöpåverkan vid investeringar i det svenska elstamnätet
During the period 2009-2013, investments in the Swedish national grid increase by a factor of ten compared to previous years. In order to fulfil their mission to manage the national grid in a safe, efficient and environmentally sound way, Svenska Kraftnät (Swedish National Grid) needs to take all these perspectives into account while planning new investments. To compare and relate perspectives of technology, economy and environment the same yard stick must be used. That yard stick is commonly money. A problem arises however as environmental issues are difficult to price.The purpose of this master?s degree project was to develop a tool for evaluation of environmental impact related to investments in the Swedish national grid.
"Man kan inte vara ledare om man inte har några följare" : En kvalitativ studie om hur chefer upplever sin position
According to science internal communication is a complicated, yet very important, issue of organizations today. An organization with a successful internal communication shows better results both economically and in terms of coworker satisfaction. The two main theories on communication are sensemaking and transmission. After a century with a transmissionary point of view, researchers stress the importance of sensemaking internal communication.Main question of this thesis is ?Which of the two main theories is the most useful when anchoring important messages in large organizations??According to the results of this study, conducted by interviews, neither one is more useful than the other.
Lyftkraftsberäkning för vingprofiler: Virvelpanelmetoden
The problem presented in this report is that of finding a method to calculate the lift force from a single-element airfoil of arbitrary shape. A number of restrictions are used in order to simplify calculations while retaining reasonable accuracy. The problem is solved for the two-dimensional case only and no finite-wing effects are taken into account. Furthermore, inviscid and incompressible flow is assumed. The method used to solve the problem is the vortex panel method, with vortex singularities distributed over simplified airfoil geometry.
Ekonomi i Passivhus : En studie av två verkliga byggnader
The aim of this report was to investigate the economy of passive houses. The work was focused on economy in total and on the economy of different components such as windows, insulation, heat exchanger and the air tightness of the climate shell. No attention was paid on the comfort factor or to the impacts on the environment.Two houses, aspiring to be passive were chosen; A big one and a small one. Hence, comparisons considering the size of the building have been possible to do as well.The comparisons were made by calculating ?break even? between two concepts; passive and BBR- concept.
Utredning av värmesystem i Boliden AB:s anläggning vid Tara-gruvan
Sommaren 2009 besökte WSP en anläggning i anslutning till Taragruvan i Navan, Irland. Syftet av deras besök var att se över ventilationssystemet som var föråldrat. I och med besöket insåg besiktaren att även deras värmesystem var i behov av en uppdatering och den uppgiften resulterade till detta examensarbete. Det övergripande syftet med arbetet är att undersöka hur ett nutida värmesystem kan byggas upp och förbättra inomhusklimatet jämfört med ett äldre system. Uppgiften i arbetet består av att ta fram ett förslag på utformningen av ett nytt system som tar hänsyn till effektbehov och dagens klimatkrav. Utredningen hänvisar en anläggning som används till omklädningsrum för gruvarbetarna samt kontorslokaler. Där är inomhusmiljön bristande, speciellt i omklädningsrummet där temperaturen och den relativa fukthalten är över rekommenderande värden.
Statusbedömning och förbättringsförslag för startkedjemaskineri, startkedja och linspel för stränggjutningsmaskin
The main goal with the master thesis has been to do a status evaluation of the chain machinery with its start chain and wire to secure the production on a short basis due to that a reconstruction is not planned at this time. An evaluation of the condition of the start chain and the rollers in the chain depository has been done. An offer has been requested for a new start chain and the evaluation of the start chains may be a basis for the decision taking. The production has been able to go on, although it has arisen some problems which have been difficult to find the causes for. There is no gathered ?picture? of the machinery status and a mapping of each machinery has been compiled of comprehensive logs.
Lönsam energieffektivisering : Ett samarbete mellan ÅF och kund
This thesis project has focused on studying ÅF?s business concept Energy Collaboration, which is their way of selling energy efficiency services. Thereforeongoing projects have been analyzed. The purpose was to determine achieved energy efficiency, costs and profitability for the studied projects. It was concluded that the Energy Collaboration is a good way of selling energy efficiency services, since the customer takes no risk and energy savings of about 15-25 % can be achieved with simple measures.
Val av energisystem för en hållbar stadsdel : En fallstudie av Östra Sala backe
Uppsala County has ambitious environmental aims for the planned residential area inÖstra Sala backe. In this thesis different energy sources have been evaluated todetermine which system that would be most favorable given currently availableinformation about the project. Planned energy usage has been divided into tap waterheating, space heating and power. Three base case scenarios were made with districtheating, small scale bio fuel and heat pump. Solar power and solar heating were thensimulated and the production from the two could individually be deducted from theenergy need in the base cases, constituting 9 different scenarios.
Prefabricerade Passivhus
European Union has made a new decision that all new built houses by 2020 shallbe near-zero energy houses. Boverket?s definition of near-zero energy housesintends buildings with good energy performance in which a proportion of theamount of energy that must be added to the building is made of renewable energy.Passive House is a set of requirements from FEBY designed to build energyefficient buildings. This is achieved by reducing loss of heat through the buildingenvelope and to take advantage of the passive heat from solar radiation,installation and heat sources like people living in the house.This project has been made with help of Anebyhus and one of their model houseshave been examined from the report?s issues, including Anebyhus?s energyperformance, requirements for the manufacturing and assembly, how theenvelope must be improved to fulfill the requirements for the Passive House andwhat energy calculation programs are available on the market.The report aims to provide solutions for energy efficient houses that are adaptedfor production of house building.Two visits to Anebyhus has been done to study their manufacture and assemblyof building elements.
IT-relaterade problem på arbetsplatser : En studie om äldre arbetstagares krav, kontroll och sociala stöd i IT-relaterade arbetsuppgifter
According to science internal communication is a complicated, yet very important, issue of organizations today. An organization with a successful internal communication shows better results both economically and in terms of coworker satisfaction. The two main theories on communication are sensemaking and transmission. After a century with a transmissionary point of view, researchers stress the importance of sensemaking internal communication.Main question of this thesis is ?Which of the two main theories is the most useful when anchoring important messages in large organizations??According to the results of this study, conducted by interviews, neither one is more useful than the other.
Restspänningar i arc-förångade (Ti(1-x)Al(x))N ytskikt
This report is the written documentation of a project work carried out at the Division of Engineering Materials at Luleå University of Technology in cooperation with Seco Tools AB. The project deals with the analysis of residual stresses in Ti-Al-N thin film grown on WC/Co cutting inserts. The composition of Al varied from 0% up to 75%. Increasing the Al content in the Ti(1-x)Alx N compound improves the compressive residual stresses even after annealing of the material. The experiments have been performed in a high temperature x-ray diffractometer (HTXRD) where the interplanar atomic spacing was determined in-situ and subsequent converted into stresses.
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..
Befuktning av inandningsgas i en ventilator
Långtidsbehandling med ventilator utan tillräcklig befuktning kan torka ut en patients luftvägarmed olika komplikationer som följd. Målet för detta examensarbete var att utveckla en ny teknikför att befukta och värma inandningsgasen. Ett fungerande koncept och en prototyp som styrkerkonceptet skulle tas fram.Marknaden för befuktare studerades och de vanligast använda befuktningsmetoderna granskadesför att hitta svagheter som behövde åtgärdas. De två vanligaste befuktartyperna är HeatedHumidifier och Heat and Moisture Exchanger. Den främsta nackdelen med Heated Humidifiervar dess tendens att övermätta luften med kondensutfällning som följd, och med Heat andMoisture Exhanger att inte tillräckliga fukt- och temperaturnivåer nåddes.Därför togs en ny design fram med målet att kunna styra fukt och temperatur oberoende avvarandra.
Köldbryggor och energiförluster. En studie om energiförluster genom balkonginfästningar och deras betydelse för byggnadens totala energibehov
In this report the balconies? abutments for a property in Bo01-area in Malmö has been studied. The property which is called Vitruvius contains four build-ings where two of them have corbelling balconies with intermittent abutments. With intermittent abutment means that the 50 mm thermal bridge insulation that the balconies is equipped with, is broken regularly by a 300 mm concrete heel. The reinforcement bar that holds the balcony runs through this heel.