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667 Uppsatser om Temperature dependence - Sida 4 av 45
CFD simulering av kallras : Undersökning av temperatur- och luftbeteende intill höga glasfasader och i vistelsezon med golvvärme som en värmekälla
Glass has sophisticated front properties and are used as facades in high buildings. During cold periods, these glass facades could cause thermal discomfort, due to cold downdraught. Cold downdraught can be countered by placing heaters under glass surfaces. Nowadays technology offers highly insulating windows, which is why there is an interest to investigate the indoor climate with only underfloor heating. The research in this area is limited, and few empirical methods are available.
Mystiken kring styrelsearbete - skillnader i styrelsearbetet i ett litet börsnoterat bolag och ett litet onoterat bolag
New laws and recommendations within corporate governance during the last years have affected the way board of directors work. The board is said to have and fulfill three roles: a control role, a service role and a strategy role. These roles could be understood by three theoretical theories: the agency theory, the resource dependence theory and the stewardship theory. The purpose of this study is to investigate whether, and if so how, the board work differs between two small firms based on these roles, given that one of the firms is a publicly listed firm and the other is a privately owned firm. Using a qualitative case study as research method we find that the board work differs between the two companies when it comes to these roles.
Utveckling av en ytmonterad fördelningsmätare som underlag för individuell debitering av vattenförbrukning i fastigheter
The master thesis, conducted at Metrima AB, concerns the development of a non-intrusivedistribution meter as a basis for individual tap water billing in apartments.The project is conducted in response to the market interest in individual tap water billing inapartments as an answer to environmental concerns regarding water consumption. Due to thehigh installation cost of traditional water meters, a new method of determining waterconsumption, without having to cut water pipes, is proposed.The proposed method distributes the total water consumption for an apartment complex toindividual apartments according to distribution meters, measuring water run-time, in eachapartment. The water run-time is estimated by measuring the water pipe?s outward vibrationsand temperature changes.A test environment was established and a prototype built, using a tilt- and vibration sensor forvibration sensing and a precision temperature sensor to measure temperature changes. As bothsensors work well in the test environment, further testing was done in 3 apartments for aduration of 5 days.
Sekundärnät för lågtempererad fjärrvärme
Lower energy use in buildings is a result of increasingly stringent energy requirements across Europe. When conventional district heating technology is used in areas with low energy consumption heatlosses do not fall even though the amount of energy delivered is reduced. This reduces income for thedistrict heating company. To maintain their economic viability the district heating companies? majorchallenge is to implement new solutions that minimize heat loss.
Klimatet på tre platser i Sverige 2071-2100 i jämförelse med Europas klimat 1961-1990 med fokus på temperatur, nederbörd och avdunstning : En analytisk studie från en simulering av Rossby Centres regionala klimatmodell, rca3.
Due to human influences on the climate an increase in Earth's mean temperature is today an accepted conception. With a rising temperature discussions have started how the climate in an area will change in the future. Equally interesting and important is it also to study the precipitation in an area. Precipitation is the factor, next to temperature, that affects most how a climate in an area looks like and feels. Since precipitation is connected to evaporation the latter parameter is also of interest to study.
Undersökning av bindningsmekanismer vid pressning av metallaminat : Investigation of bondning mechanisms at the pressing of metal laminates
Increased understanding of the mechanisms that operate in conjunction with the welding of metal surfaces may help to improve existing manufacturing processes, and to enable new products and combinations of materials. The purpose of the project has therefore been to acquire a deeper understanding of what is happening in the bond for steel and for the factors that form the basis for a bond to develop between metals in the production of laminates by pressing. The merge has been done by pressing and the surfaces after the experiments have been studied in detail in the scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX) and with interferenceprofilometry in Wyko, to provide a greater understanding of the mechanisms that influence the bonding in the interface between metals. The project was limited to contain the materials Docol 1000, HyTens 1200, Aluminum AA3003 and a commercial steel. The parameters varied in the experiments to study their influence closer are temperature, pressure, heat treatment and pretreatment. This has been implemented by pressing with varying temperature and pressure.
KOMMUNALSKATTER OCH KONJUNKTUR
Fiscal policy and its consequences have attracted much attention on both academic and societal level, in Sweden and elsewhere. However, the dependence between fiscal policy on municipality level and business cycles has only recently sparked a debate among Swedish economists. Studies point out that a law which came to force in 2000, balanskravet, may have caused municipalities to lower expenditures, alternatively raising taxes, during recessions. This thesis examines how the level of municipality taxes depends on business cycle fluctuations and the impact that balanskravet has had on this correlation. We employ econometric regressions, with annual data covering the period 1980-2014, to enable an analysis of the dependence between taxes and business cycles, both before and after the introduction of balanskravet.
Sjöars känslighet för klimatförändringar ? vilka faktorer påverkar?
The Earths climate is changing at a higher rate, i.e between 1861 and 1994 the annual mean temperature in Scandinavia increased with 0,68º C and according to recent climate models the annual mean temperature is likely to rise with another 3º C during this century.A warmer climate in many ways is associated with changing conditions for lake ecosystems. An expected higher water temperature and a stronger summer stratification of the water column increases the risk of anoxic conditions at the lake bottom. Thus anoxic conditions are likely to cause a phosphate leakage from the sediment, i.e. a higher internal loading of phosphate.In this project, the extremely warm summer of 2002 has been used as an example for a possible scenario for a future climate. By comparing levels of phosphorus in the summer of 2002 with a ten-year median value, a phosphorus related sensitivity to climate change has been analyzed for 55 Swedish lakes.
Kirunametoden-Jämförelse emot en konventionell injusteringsmetod
AbstractWith increasing population and increasing demands for comfort and thus an increase in energy demand, it is necessary to examine various energy-efficiency measures. This work deals with the ability to control the flow through the heating system to achieve the desired comfort with as little energy as possibleA heating system contains of different parts, roughly speaking, you can divide it to three main components: Heat source, Distribution and Heat emitters. All components are working together to bring heat to the building. What is examined in this report are different ways of adjusting the flow and supply temperature and how it affects comfort and energy use in a building.At today ?s date the conventional method is to use a high flow through the heating system, which affects pressure drop and cooling of the fluid.
Utvärdering av befintliga passivhus : En byggnadsfysikalisk bedömning och mätningar om temperatur, och fukt analys på ytterväggarna
Energy price are on the way up to a high level that will not diminish in the future make us to focus more on the sustainable development for a better solution of residential houses. Passive house or low energy housing are one of the solution to make residential more environment friendly, in same time it´s a financial security using less energy, and saving money. The last 10 years in Germany and all around Europe the concept of passive house been developed, and people aim to know more about these concept that leading the market more attractive for passive houses. A passive house is a well designed building highly insulated and air tight with mechanical ventilated system for the whole building envelope that minimizes the use of energy for heating [1].The housing company Mimer has chosen to invest in low energy consumption in every new housing project. These future plan projects are decided to use less than 75 kwh per square meter annually in purchased energy [2].This thesis is about new constructed passive houses, and focuses on the evaluations of the temperature, and moisture condition for attic, external walls and joist.
DYNAMIKEN OCH EFFEKTEN AV MARINA V?RMEB?LJOR P? TROPISKA KORALLER (SCLERACTINIA)
Marine heatwaves (MHW) have become increasingly common in recent decades due to greenhouse gas emissions that have caused climate change. A marine heatwave is when the sea surface temperature rises, which damage many different ecosystems in the sea. One ecosystem that is sensitive to temperature changes is tropical coral reefs, which are at risk of bleaching during marine heatwaves. Coral bleaching is when its symbionts leave the coral and they lose their color, while also starving to death as they lose their food source. The purpose of this report was therefore to investigate what the connection between marine heatwaves and coral bleaching looks like, and to see if there are any geographical differences.
Förklaringsmodeller till missbruk och beroende inom missbruksvården. : En kvalitativ studie av socialarbetares förklaringsmodeller vid bedömning av insats för personer med missbruksproblem
The purpose of this study was to study social work models to explain addiction in the assessment of response to people with addictions. This study investigated how social workers' explanations are shaped by their experiences, theoretical points influenced by research in a discretion is affected by organizational conditions, manuals, evidence-based practice and national guidelines in an investigative process. The material in this study has emerged through interviews with four social workers in the social services department for addiction and dependence. The essay is a qualitative study with personal interviews as the basis for the result. The study begins with a description of addiction and dependence, current laws on the matter, and officer's work.
Stafettläkare - Räddaren i Nöden?
During a long period of time, rental doctors have created a vast debate in Sweden. Currently, there is a shortage of doctors working in Sweden and to guarantee the lawful right to healthcare of high quality the counties must hire doctors through employment agencies. There are different opinions about rental doctors, some thinks the temporary employment results in a negative work environment and furthermore puts the patients at risk. Other people consider the Swedish healthcare to not function without rental doctors. The purpose of this essay is to investigate rental doctors through a legal perspective and how temporary employment actually affects the patients? security and the work environment in Sweden?s healthcare.
Skuggvävens effekt på fryslagrade täckrotsplantor av tall (Pinus sylvestris) i upptiningsstadiet :
This project was an assignment by Sveaskog and Svenska Skogsplantor. The purpose was to study the effect of protective fabric on the thawing stage of frozen pine seedlings. The function of the protective fabric is that it should protect the seedlings against strong sunlight and create an even temperature inside the boxes containing the seedlings. The result has shown that there was no statistically significant difference when the protective fabric was used or when it was not used, although this was probably due to the weather conditions. The study was carried out under cold and cloudy weather conditions and probably would have given other results if there had been more sunny days with a higher ambient temperature.
Högtempererat borrhålslager för fjärrvärme
The district heating load is seasonally dependent, with a low load during periods of high ambient temperature. Thermal energy storage (TES) has the potential to shift heating loads from winter to summer, thus reducing cost and environmental impact of District Heat production. In this study, a concept of high temperature borehole thermal energy storage (HT-BTES) together with a pellet heating plant for temperature boost, is presented and evaluated by its technical limitations, its ability to supply heat, its function within the district heating system, as well as its environmental impact and economic viability in Gothenburg, Sweden, a city with access to high quantities of waste heat.The concept has proven potentially environmentally friendly and potentially profitable if its design is balanced to achieve a good enough supply temperature from the HT-BTES. The size of the heat storage, the distance between boreholes and low borehole thermal resistance are key parameters to achieve high temperature. Profitability increases if a location with lower temperature demand, as well as risk of future shortage of supply, can be met.