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401 Uppsatser om Straw fuel - Sida 12 av 27
Tail posture and motion as a possible indicator of emotional state in pigs
In the current study, the aim was to investigate whether tail posture and motion can be an indicator of the emotional state of pigs and if the tail posture of the pig is affected by social breeding value (SBV), coping style and/or housing. Emotional state can be defined in two dimensions: valence and arousal. Two batches of 96 finishing pigs were studied in a one generation selection experiment with a 2x2 set up and were housed in a barren or straw bedded pen. In each pen, 6 pigs (3 male, 3 female) were housed. A back-test was done to determine the coping style of the pigs with two categories; high resister and low resister pigs.
Outnyttjade resurser inom park- och naturvård
As a small and land scarce country, effective waste management is ofoutmost importance in Singapore. In this study the production of biogasthrough anaerobic digestion from the organic fraction of municipal solidwaste (OFMSW) was compared to incineration of the waste. At the momentalmost all of the OFMSW in Singapore is incinerated. Three differentscenarios were compared to the reference scenario (incineration): one with alarge scale biogas plant that can treat half of all OFMSW in Singapore, onewith a medium scale biogas plant about 15 times smaller than the large oneand one with a small scale biogas plant that can treat waste from e.g. ashopping center or a food center.By using life cycle assessment (LCA) the different scenarios were comparedin terms of global warming potential (GWP), acidification, eutrophication,energy use and land use.
Design av försöksanläggning för trycksatt rökgasrening vid oxy-fuelförbränning
Reducing the CO2-pollution, resulting from the combustion of fossil coal for energyproduction, is important to affect environmental changes. One way to achieve a reductionis to use the oxy-fuel technology. The technology uses O2 and re-circulated flue gasduring the combustion which results in a flue gas mainly consisting of CO2. The flue gascould then be compressed and stored without environmental effects. A problem thatfollows from the compression is the risk of acidification in sensitive parts of the process.Acidification can occur because of reactions following from the contact of condensedwater and sulphur- and nitrogen-oxides which are also present in the flue gas.This report compiles and evaluates the basis of a scientific unit with the purpose ofexploring the possibilities of extracting impurities of SOx and NOx from the flue gases.The dimensions of the unit are based on basic conditions, defined for an existing oxy-fuelprocess at Chalmers, and on the results of computer modelling.
Vindkraft eller kärnkraft - En jämförelse
The scope of this project is to make a comparison of costs associated with wind and nuclear power in order to decide which one of these is the most suitable in the case of an increased demand for electricity. It is also investigated if there are other factors that can influence the choice of energy source.An average cost is calculated in terms of kronor per kilowatt-hour (SEK/kWh) using cost of investment, operation & maintenance and taxes & subsidies. Total investment cost is recalculated to production cost using the annuity method at three different interest rates (6%, 9% and 12%).The comparison is made between three cases of wind power and two cases of nuclear power. For wind power there are two ocean-based (300MW and 100MW installed capacity, respectively) and one land-based (60MW) wind farm. For nuclear power there is one EPR-reactor (1600MW) and one AP1000-reactor (1100MW).
Beteenderesponser hos farmuppfödda minkar (Mustela vison) hållna i stora och berikade burar :
The standard housing of farmed mink provides little opportunities for them to behave naturally and abnormal behaviours such as stereotypic behaviour and tail biting may occur. To prevent abnormal behaviours animals in captivity are often provided with different kinds of enrichments. The aim of this study was to investigate what kind of enrichment farmed mink use when they have several kinds to choose from and to observe if abnormal behaviours can be decreased with a larger cage and a more multifaceted environment.
Totally 20 silver blue, 10 months old female mink were kept in traditional cages (80x30x40 cm) for 7 days and in larger cages (195x80x40 cm) with several types of enrichments for 7 days. The enrichments were wire net- and wooden shelves, wire net- and plastic cylinders, water bath, plastic ropes, branches, straw and tennis balls. One-zero scan sampling on behaviour and choice of place were performed during 3 hours and 20 minutes prior to feeding during 7 days per treatment in April 2004.
Beräkning och loggning av bränsleförbrukning samt implementering av MOST
Huvudmålet med examensarbetet var att konstruera en utrustning för mätning samt loggning av dieselförbrukning på en buss. Det fanns dessutom en önskan att ett MOST-nätverk skulle konstrueras. Detta skulle användas på 2005 år Formula SAE-bil vid Luleå tekniska Universitet. Olika metoder diskuterades och arbetet resulterade i en prototyp som mäter och loggar både bränsleförbrukning och körsträcka på Luleå Lokaltrafiks bussar. Även ett mindre MOST-nätverk upprättades men med ett icke tillfredställande resultat..
Beräkning och loggning av bränsleförbrukning samt implementering av MOST
Huvudmålet med examensarbetet var att konstruera en utrustning för mätning
samt loggning av dieselförbrukning på en buss. Det fanns dessutom en önskan
att ett MOST-nätverk skulle konstrueras. Detta skulle användas på 2005 år
Formula SAE-bil vid Luleå tekniska Universitet.
Olika metoder diskuterades och arbetet resulterade i en prototyp som mäter
och loggar både bränsleförbrukning och körsträcka på Luleå Lokaltrafiks
bussar. Även ett mindre MOST-nätverk upprättades men med ett icke
tillfredställande resultat.
Att återställa en naturlig ordning : skogshistoria och restaureringsbränning i Långsidbergets naturreservat
During the late 1800s fire suppression became increasingly effective in northern Sweden which led to decreased areas of fire-disturbed woodland and successive changes in the structure of forests. In the long run this can pose a serious threat to fire-dependent and fire-favored species. Today some fire-prone forest reserves are burned as a nature conservation act. Often partial cuttings are made before burning, with somewhat different motives. The purpose of the study in Långsidberget nature reserve was to give a general picture of forest history and its affect on today?s forest condition, and to show how partial cuttings affect burning conditions and results.
Långsidberget is located close to areas that were colonized during the Middle Ages.
Environmental impact assessment of energy recovery from food waste in Singapore : comparing biogas production to incineration
As a small and land scarce country, effective waste management is ofoutmost importance in Singapore. In this study the production of biogasthrough anaerobic digestion from the organic fraction of municipal solidwaste (OFMSW) was compared to incineration of the waste. At the momentalmost all of the OFMSW in Singapore is incinerated. Three differentscenarios were compared to the reference scenario (incineration): one with alarge scale biogas plant that can treat half of all OFMSW in Singapore, onewith a medium scale biogas plant about 15 times smaller than the large oneand one with a small scale biogas plant that can treat waste from e.g. ashopping center or a food center.By using life cycle assessment (LCA) the different scenarios were comparedin terms of global warming potential (GWP), acidification, eutrophication,energy use and land use.
Livscykelanalys: Pelletspanna från kvänum energi
This study will identify the environmental impact in terms of carbon dioxide for a boiler house on behalf of Kvänum energi. The boiler central consists of a main building, which in turn contains multiple components such as boilers, pipes, etc, the boiler central uses pellets fuel. It also includes a silo and an ash container. The total weight of the boiler is about 63 tons. Each boiler has an output of 600 kW; the central includes three boilers with room for a fourth if necessary.
Det växer så det knakar! Vad påverkar konsumentens val av återhämtningstillskott
Syfte Vi har för avsikt att öka förståelsen för hur valet av återhämtningstillskott styrs av konsumentens beteende och analysera i vilken grad olika faktorer påverkar detta val. Vår förhoppning är att denna insikt skall kunna bidra till att minska det informationsbehov som företag i denna bransch ställs inför där de idag kan ha bristfällig information. Metod För att besvara de frågeställningar som uppkommit under problemdiskussionen har vi använt oss av både primär och sekundär data. Vi har utgått från den sekundärdata vi insamlat för att få en teoretisk bas att stå på. Den primärdata vi insamlat baserar på kvalitativa djupintervjuer och samtal med sakkunniga.
Hållbara uppvärmningsalternativ för Grinda Wärdshus : En studie om uppvärmning med pellets och flis
This report is a bachelor's thesis of two students from the Energy and Environment degree at KTH Stockholm. Grinda is an island situated Stockholm archipelago. Skärgårdsstiftelsen is landowners and manages the area. Grinda Wärdshus, a guest house located in the island, currently uses an oil-fired boiler as a heating system. The aim of this thesis is to investigate whether wood chips or pellets is, from a sustainability standpoint, a suitable heating method for the guest house.
Fukthalt i GROT - påverkande faktorer :
This study was carried out at the request of the bio energy company Naturbränsle. The company handles annually 750 000 m3 of chips from logging residues from a large area, from Östergötland in the south to Härjedalen in the north. In that area, about 50 bio fuel plants are customers. When Naturbränsle deliver chips from logging residues to their customers, the moisture content varies from 30 % to 60 %. The aim of the study was to sort out the affecting factors on the moisture content in the chips during handling and storage processes.
Utnyttjandet av ligghallar hos dikor och kvigor av köttras under vintern :
Cattle used for meat production can be held outside all year round and due to the legislation they should have access to shelters or other buildings for protection against the elements giving them a dry and clean bedding. There are different opinions concerning their need of protection and the question about necessity of shelters for cattle is of current interest due to a less profitable economy in meat production and the investment costs for shelters. The aim of this study was to acquire more knowledge about the natural behaviour of cattle concerning their use of shelters. The basis of the study was a series of questions regarding when animals choose to stay in shelters, if shelters were used less when they had access to protecting vegetation, how temperature and weather conditions affected the use of shelters and the influence of distance between shelter and feed. Behavioural studies was conducted at five different farms where six groups of suckler cows and heifers of following breeds and crossbreeds were observed; Aberdeen Angus, Charolais, Hereford, Scottish Highland Cattle, Simmental and the Swedish breeds SKB and SRB.
Modellering av en panna med rörlig rost :
The aim of this master thesis was to create a dynamic model for the processes in a solid fuel boiler of the moving grate type. Another aim with the model was to keep it as simple as possible but still able to catch the dynamics of the processes in the bedplate of the boiler. The creation of the model had its origin from drying and combustion equations used in earlier modeling work of boilers. The represented model has been used to simulate different kinds of disturbances in a boiler and different ways to control the boiler. These tests show that controlling a number of parameters in the bed of the boiler is an effective way to keep the grate stable during disturbances.