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957 Uppsatser om Thermal heat losses - Sida 58 av 64
Gröna lösningar - en fallstudie av aktuell teknik för energieffektivitet för Skanska Sverige ab
ur society is today in a phase of development in environmental and sustainable thinking. Alarming reports show changes in climate caused by our load and exhaust of resources. The energy usage contributes to a big part of it, by its emission of carbon dioxide. The built environment uses around 40 % of the total energy consumption in Sweden and requests to strongly reduce it are presented from both EU and national level.This thesis brings up the subject of green building with a focus on how we can create more energy efficient buildings in projects of new construction. Since the construction industry today often fails to pass on the knowledge between different projects, as a return of experiences, the construction company Skanska suggested the topic for this thesis.
Är en schimpans bättre på att skapa avkastning än en professionell fondförvaltare? : En jämförande studie om historisk avkastning av förvaltade fonder och slumpmässigt genererade portföljer
Background: Investors have several options to choose from when the goal is to achieve the highest yield at the lowest cost and risk. Stocks are a common investment options, but is also associated with risks. Portfolios are usually constructed with several different assets to reduce the unsystematic risk of investment. Funds are similar to composite stock portfolios, the big difference is that they dealt with in their entirety and investors may not affect the fund's content. The problem remains that whether you choose stocks or mutual funds there is still uncertainty as to how the future will unfold.
Biodiversitet av evertebrater på vegetativa tak
In a city sometimes conflicts arise between either to save the species-rich vacant lots where many species thrive, or to build new buildings. Green roofs can then serve as a refuge for plants and animals that have had their natural habitat destroyed or diminished. Today we know too little about green roofs contribution to the biodiversity in the cities. We also know very little about how various types of vegetation on roof can increase biodiversity and its ability to attract different species.The aim with this study was to examine how different types of vegetation on the roofs affect the biodiversity of the invertebrate and how species-composition and number of individuals differ between the roof- and groundlevel.This study has been carried out on Augustenborg Botanical Roof Gardens in Malmo, and in an area about 1.5 kilometers away from Augustenborg. Three different types of vegetation on the roof and ground floor were selected: sedum- ruderal and grass.
Utvärdering av energibesparingspotential vid tillämpning av värmepump i diskmaskin : OBS! Sekretessbelagd tills vidare
För ett genomsnittligt småhus i Sverige idag går ca 5000 kWh till hushållsel. Av dessa 5000 kWh går 7% till att driva diskmaskiner. Effektiviseringen av diskmaskiner har framförallt strävat efter en låg vatten- och energianvändning, en kort processtid samt en effektiv rening av disken.Det finns dock gränser för hur effektiva diskmaskinerna kan göras med traditionell teknik. Därför har producenter under de senaste åren börjat se sig om efter mindre traditionella metoder som till exempel bruket av en värmepump för att få ned energiförbrukningen.Syftet med det här examensarbetet har varit att ta fram systemlösningar för värmepump i diskmaskin samt att utvärdera energibesparingspotentialen i denna tillämpning.Målet har varit att ta fram och beskriva de möjliga systemlösningar som uppstår vid en idégenerering. Att välja ut två lösningar för närmare undersökning, att bestämma en lämplig kompressoreffekt samt att beräkna energibesparingen dessa lösningar ger.En litteraturstudie har gjorts av teknik och tillämpningar inom området, som till exempel värmeväxlaranvändning i diskmaskiner samt användandet av värmepumpar i andra vitvaror.
Rött, vitt, svart - Vedisk kosmologi och klassificering i Ch?ndogya-Upani?ad 3:1-11 och 6
Chapter 6 of the Ch?ndogya Upani?ad has often been treated in works on early Indian philosophy, as well as in some comparative studies on color symbolism. Attempts to place it in a larger framework against the background of late Vedic religion are, however, few, the rationalistic and ?tradition-challenging? appearance of the text having repeatedly been emphasized. But the doctrine contained in the text ? a cosmologic teaching on the three elements constituting the universe, each being characterized by a color (red, white, black) ? and their microcosmic counterparts in the human body, does have some clear affinities to the worldview of the Br?hma?as and ?ra?yakas, which posits a series of similar correlations (bandhu-) between macro- and microcosmos.
Karaktärisering av Gremmeniella-skadade bestånd inom Holmen Skog AB :
Since the end of the eighteenth century forest damage caused by the pathogen Gremmeniella abietina has been observed and documented. During the latest epidemic in Sweden more than 480 000 hectares forest land have been injured and this has lead to considerable economic losses. For the pathogen to succeed with infection, spore dispersal and colonization the right environmental conditions is required. The aim of this paper is to describe the diseased stands using site and stand characteristics and to evaluate the effect of these variables on the disease incidence. Further, the thinning performed during the time for spore dispersal and its relationship to injured stands is examined.
Klimat i miljökonsekvensbeskrivningar : hantering av klimatförändringar och extrema väderhändelser i MKB
There has always been global warming on earth and it is because of it that the earth is inhabitable. Without global warming the temperature on earth would be around -18 ° C instead of today's + 15 ° C. Global warming is generated by greenhouse gases like carbon dioxide and methane which trap long wave radiation in the earth's atmosphere. The problem today is that the global concentration of green house gases has significantly increased since the 1750's as a result of human activity. Today's values widely exceed the preindustrial values.
A screening for Schmallenberg virus among sheep, goats and cattle in Zambezia province, Moçambique : and preparations for a metagenomic survey of virus in mosquitoes
As the world´s population increases and people's living conditions are improving, larger areas are needed for houses as well as food production. This means that
new areas are exploited and that people, livestock, blood sucking insects and wild animals are forced to live close together. In combination with the global warming,
leading to extreme weather such as floods and storms, this allows both new and old pathogens to emerge. The number of "emerging infectious diseases", EIDs, has increased in recent years and many of them have their origin in poor, tropical countries. Moçambique is therefore considered to be a high risk area for EIDs.
Schmallenberg virus, SBV, was discovered in 2011 as an "emerging infectious disease" in dairy cows in Germany.
Leanuppgift för industriprogrammet
The government regulations for energy use in buildings will be tightened in the future. At the same time the interest in environmental classifications and certifications of buildings is increasing. This has meant a new situation for solar energy. The designs of solar heating systems are often based on experience and/or rules of thumb, rather than calculations and simulations. This thesis examines whether simulation tools, in this case Polysun, are useful in this work.
Ersättning för lidande enligt frihetsberövandelagen : En analys av hur grunden för frihetsberövandet påverkar ersättningens bestämmande
The purpose of this study is to investigate a group of female converters and their subsequent experiences when transitioning to islam by bearing hijab. The study analyzes how this religious conversion has shaped and influenced the identity of mentioned women, as well as their attitude and relationship to the social environment prior to and after converting. This means that in accordance with the purpose of this study, an attempt to reveal the everyday life of these women will be performed. In order to make this study possible, three different methods will be put to use. A narrative method that touches upon the time leading up to and after the final converting and the impact of the conversion.
Monitoring and pest control of Fruit flies in Thailand : new knowledge for integrated pest management
Fruit flies (Tephritidae) are serious pests that cause enormous losses for farmers in many countries. The frequent use of insecticides in controlling fruit flies in fruits and vegetable has not resulted in sustainable management of the pest. Problems associated with this complete reliance on chemical control are many residues of insecticides in crops, health problems for farmers, contamination of water and soil, insecticide resistance development and decrease in natural enemy populations. The implementation of control measures that do not imply an added burden to the environment and/or the farmers is urgent. More knowledge about the ecology of fruit flies is the basis for finding new and better ways to control this pest.
Småskalig elproduktion i Arvika
Arvika Fjärrvärme AB, a district heating company from Arvika, today cover 74 % of their total energy production with biofuel wich runs a 16 MW bioler giving process water at saturated liquid state.In recent years Vaporel AB has introduced a new tecnique that gives an external generation of steam after boilers. The concept is built on an adiabatic pressure drop of the saturated liquid in a so called Flashbox which makes a small part of the liquid to evaporate. The generated steam is lead into a turbine where electricity is in a conventional manner.The purpose with this rapport was to do a basic study for the specific system at Arvika where it?s possible to see the potential production of electricity that follows an installation of a flasbox.The final goal was to introduce an economic analysis of a flashox installation at given conditions.To reach our goals we have created a model in Excel where we used the given conditions at Arvika Fjärrvärme to do our calculations. The model has been tested at three different states, of process water returning to potboiler, to be able to decide the optimal operation for the system at present.The studies have resulted in a pressure of the processwater at 14,5 bar (at) and a pressuredrop to 9,5 bar (at) in the flashbox.
Simuleringsprogram som verktyg vid projektering av solvärme
The government regulations for energy use in buildings will be tightened in the future. At the same time the interest in environmental classifications and certifications of buildings is increasing. This has meant a new situation for solar energy. The designs of solar heating systems are often based on experience and/or rules of thumb, rather than calculations and simulations. This thesis examines whether simulation tools, in this case Polysun, are useful in this work.
Interdependence between seed age and aerated steam treatment intensities
Aerated steam treatment is a modern and environmental friendly method for seed borne fungus sanitation, mainly used on cereals. The method involves exposure to heat and high humidity, factors which are known to induce a fast ageing of seeds, thus resulting in reduced storability. This thesis clarifies the interdependence between seed age and the aerated steam treatment intensities.
Two studies were carried out in this thesis. In the first study the storage longevity of seeds treated with aerated steam was examined. The second study investigated the shelf-life of the pre-tests used to determine the aerated steam treatment tolerance of a seed lot, by testing the treatment tolerance of seeds aged prior to the treatment.
Prefabricerade passivhusväggar
Background: The most energy efficient houses today are so called passive houses. These houses achieve high energy-efficiency partly by having well insulated walls. U-value describes the amount of heat transfered through a building element, the more insulation, the smaller U-value. A typical passive house wall have a U-value of 0.10 W/m2,°C. The passive houses are primarily made as small family houses and not as a block of apartments.