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957 Uppsatser om Thermal heat losses - Sida 54 av 64

Att sänka temperaturer i stadsmiljö : en studie av trädens effekt på en bostadsgård i Malmö

Under de senaste årtiondena har det pågått en förtätning och en alltmer ökad utbyggnad av världens städer. Som en följd av detta har stadens naturliga vatten- och värmebalans rubbats. På bekostnad av vegetativa ytor har artificiella byggmaterial introducerats som absorberar värme från solens strålar och höjer stadens temperaturer. Dessa material leder även snabbt bort regnvatten samt hindrar vatten att infiltreras ner i marken. Temperaturskillnader på 12oC jämfört med den omkringliggande landsbygden har kunnat uppmätas i stora amerikanska städer. Detta fenomen har kommit att kallas Stadens Värmeö eller Urban Heat Island som är den engelska termen. I Sverige förväntas det bli allt högre sommartemperaturer och fler rekordvarma dagar framöver.

Hållbara energilösningar för Sala silvergruva : En studie av energisystemet och effektiviseringsmöjligheter

Sala Silvergruva AB är ett av många företag som just nu kämpar med höga energi-kostnader. Denna rapport undersöker vilka möjligheter det finns att skapa ett hållbart energisystem i Sala Silvergruva med avseende på ekonomi, miljö samt sociala aspekter. Rapporten undersöker nio tekniker; vindkraft, vattenkraft, solfångare, solceller, pelletspannor, värmepumpar, effektivisering samt lagring av värme från växthus respektive fjärrvärme. Dessa analyseras var för sig med utgångspunkt i tio krav som speglar hållbarhetsaspekterna. I samband med analysen ges rekommendationer angående investering i respektive energilösning. Rapporten mynnar ut i en resultatskarta där det tydligt framgår vilka krav de olika teknikerna uppfyller. Den följande diskussionen leder fram till en slutsats som presenterar vilka åtgärder som bör vidtas i syfte att skapa ett uthålligt energisystem för Sala Silvergruva AB. Pelletspannor och värmepumpar visar sig i nuläget vara de mest uthålliga tekniklösningarna.

Granskning av hur ett miljöledningssystem uppfyller kraven i SS-EN ISO 14001:2004

The purpose with this report is to make a contribution to Bodycote heat treatments workshop in Värnamo, how to introduce, establish and constantly improve its environmental system. The rapport will help Bodycote with there certifying in ISO 14001: s demand standard. Organizations who continuously work with environmental issues have a lot to gain. Two things an active environmental development process will convey are, building of thrust within the circle of customers, and great financial savings. An increasingly numbers of organizations realize the importance to introduce a functioning environmental system into their activity.

Trä som fasadmaterial ? behandling och beständighet

Since prehistoric time man has used wood to build their environment. The material?s availabilitycombined with its good mechanical properties has often made it the material of choice. Like allmaterials exposed to natures degradative processes the properties of wood decreases over time.Rot, UV radiation and attacks by insects and pests damage wood if not protected. Since we wantwhat we build to consist, optimizing our building materials durability is of great interest.Techniques and methods for increasing the endurance of wood have been developed in severaldifferent places and for a long time.

Salmonella prevalence in the poultry feed industry in Pakistan

Abstract One of the leading causes of food borne infections in the world is due to Salmonella by con-suming poultry products including eggs and meat. According to US Food and Drug Admin-istration (2009), 2 to 4 million cases of Salmonellosis in humans occur every year only in US. Salmonella causes wide range of diseases with enteric and typhoid fever, food poisoning, di-arrhea and gastro-enteritis. Many serotypes of Salmonella do not have host specificity and cause disease in all kinds of animals and humans. Salmonella has capability to modify accord-ing to the changing environment and it can develop resistance against routine elimination practices of sanitation, chemical treatments and antibacterial drugs. Newly established poultry industries in Pakistan are confronting various infectious diseases including Salmonellosis while in Sweden Salmonella prevalence in animal products con-sumed for humans is extremely low.

Sustainable phosphorus management of horse paddocks at Julmyra

Horse keeping is gaining an increasing interest in Sweden. During 2004 to 2010 the number of horses increased with 10 - 20 %, and was estimated to be 362 700 in 2010. Julmyra Horse Center (JHC), situated in Heby municipality, is a gated community for people sharing a large interest for horses and a vision of a sustainable horse management has been formulated. This study evaluates how the horse keeping of today at JHC, and how an expansion of the horse keeping may affect the risk of enhanced phosphorus load to the nearby lake system Vansjön ? Nordsjön.

Pedagogiska miljöer : Barns och pedagogers uppfattningar om den pedagogiska miljöns erbjudande utifrån ett genusperspektiv

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.

Greklandskrisens påverkan på bankernas interna risker : En studie om svenska storbankers kreditrisk

Background: 2009 it has occurred a crisis in some of the member states of the European Union: Spain, Portugal, Italy, Ireland and Greece. Despite, some major banks in the world had begun to recover from the financial crisis that occurred from 2007 until 2009, there were still banks who found it difficult to survive. Greece is one of the countries that suffered from the financial crisis. The high budget deficit and the unsustainable debt are underlying the crisis.Banks as financial intermediaries have important function in a nation?s economy.

Solenergi : en lönsam investering för ett lantbruk?

A possible way to reduce pollution and slow down the process of global warming is to increase the usage of renewable energy sources. One of these renewable energy sources is solar power. With the aid of solar panels and solar cells the energy from the sun can be transformed into both heating and electricity. The requirement to use the sun in this fashion is a suitable surface, for example a big roof, an angle between 40-60 degrees and that the surface should be exposed to the south. Almost every farm meets these requirements.

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.

Effekt av olika kvävegödselmedel på utvecklingen av klumprotsjuka i salladskål (Brassica rapa ssp. pekinensis)

The price trend on rapeseed the latest years has led to an increasing interest to grow the crop among many farmers in Sweden. The price trend has resulted in more than a doubling of the oilseed area since the early 2000s. For many farmers it is an advantage to increase cultivation of rapeseed because of the high proportion of cereals in the crop rotation on many farms, but it is not just benefits. The risk of the fields being infected by clubroot increases within frequent rapeseed cultivation and it often leads to subtantial economic losses. Clubroot is caused by Plasmodiophora brassicae that is a soilborne pathogen in genus Protozoa and its resting spores can be found in the soil for up to 18 years.

EN TOTALKOSTNADSJÄMFÖRELSE MELLAN CELL-, SKUM- OCH LECA-BETONG

This report provides a comparison between the products cellular concrete, foam concrete and LECA concrete. The questions to be answered during the work is how the cellular concrete stands up in cost terms to the existing competitors on the market, how the concrete products differ in design work, and in which situations the concrete varieties are preferred to use.Cellular concrete is a variant of ordinary concrete, with the difference that the ballast is exchanged from stone materials to expanded polystyrene beads (EPS). This substitution gives a product with higher insulation values but lower weight than ordinary concrete.The work was carried out by designing a survey which was sent to two hundred randomly chosen companies across Sweden, to see the building industry?s opinion of the product cellular concrete. The survey showed that cellular concrete was equals its competitors in terms of price, while the product was said to be more flexible, quicker and easier to cast.Then some of the companies, who participated in the survey, were interviewed to see more carefully, how the price, the workmanship and the time for casting and dehydration differed between the products.

Forage production and summer use by ungulates on game fields and surrounding areas

Ungulates are causing conflicts between stakeholders due to browsing damage on forests and agricultural crops. At the same time there is a big demand of keeping high ungulate densities for sports hunting and recreational purposes. Movement patterns of ungulates are strongly correlated with forage availability. Therefore, measures affecting forage quantity and distribution might be a tool to reduce the economical losses in forestry without decreasing the ungulate densities and thereby decrease the conflict between different interest groups.This study investigated the potential biomass production and utilisation of marrow-stem kale (Brassica oleracea var. medullosa), at game fields in Misterhult, Sweden, as well as browsing effects on adjacent forests.

Teknisk undersökning : Rötgaskammare för småskalig biogasproduktion

Biogas mainly consists of methane and carbon dioxide, where methane is theenergy-rich gas, and is naturally created when organic matter breaks down in absenceof oxygen, also known as anaerobic digestion. A biogas plant re-creates the anaerobicconditions inside a digester where the organic substrate is fed into and digests toproduce biogas. The gas is then used to produce energy by combustion and can beseen as a completely renewable fuel.Today, energy from biogas is used primarily by major stakeholders such asmunicipalities and thus the plants become very large with high investment- andconstruction costs. There are currently few small plants in Sweden, even though thepotential for agriculture and medium-sized to smaller farms to become self-sufficientin terms of electricity and heat is great. Farms have a natural stock of digestibleorganic material in form of manure or crops for example, which are constantlyavailable.

Den globala uppvärmningen : vad kommer att hända med morgondagens värld?

Mankind faces a serious threat. Its activities, for example the burning of fossil fuels, have led to an enhancement of the greenhouse effect - something that has given rise to a global warming. The climate is becoming warmer, a change that has important effects on the nature as well as for humans and their society. Sea level rising, extreme temperatures are becoming more common, glaciers and other ice caps melt and storms becomes more intense when they appear. The main cause is the emission of greenhouse gases into the atmosphere - carbon dioxide in particular.

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