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2900 Uppsatser om Conventional pig production - Sida 63 av 194

Samband mellan laserdata och fältdata

To make it easier for forestry planning the forest owners needs data which describe characteristics of the forest. Such data you usually get from some type of inventory. A relatively new technology which probably is getting more important in the future, is laser scanning because of lower costs. But because the laser technology is relatively new you need to compare it with conventional inventory technologies to get better understanding of the possibilities the laser technology gives. This work intends to estimate field measured characteristics of the forest from laser data with help of regression analysis and then see which of the field measured properties that best could be estimated and which laser variables that gave the best results. This study shows that heights has the best estimates, but biomass, diameter and volume also gives good estimates.

Stadens gröna pauser : rekreationsmöjligheter i Pocket parks

SammanfattningSyftet med den här litteraturstudien var att ta reda på vad det finns för möjligheter och svårigheter att producera ål i fångenskap. Med nya hållbara metoder att föda upp konsumtionsål skulle utfiskningen av glasålar minska i världen och man skulle kunna fortsätta äta den goda rökta ålen med gott samvete.Det finns välutvecklade metoder för att inducera könsmognad hos han- och honålar. Detta utförs genom att injicera hormoner och man kan därför fråga sig om det är hållbart i en produktion för framtiden. Efter kläckning av larverna finns flera viktiga faktorer att ta ställning till, så som utfodring och optimal hållning av ålarna. Även ägg- och mjölkekvaliteten spelar en stor roll när det gäller att hålla ålarna vid liv.Abstract The aim with this study was to find out how far we have come to develop reproduction strategies in eel culturing.

Könsselektering av spermier från lantbrukets husdjur

Millions of preselected progeny have been born since the development of The Beltsville Sperm Sexing Technology 1986. The method is based on flow cytometry and sorting is done on the basis of DNA difference of the X- and Y-chromosomes. Preselection of progeny provides an opportunity to obtain genetic gain and increased production as well as increased animal welfare and decreased environmental impact. However, the method is associated with low fertility, high costs and uncertainty whether the sorting process contributes to DNA damage and thereby results in genetically impaired progeny. Today, sex sorted sperm is only commercially available in the bovine industry, due to the fact that bull sperm is more suitable for selection than sperm from other species.

Biogasproduktion genom tvåstegsrötning av drankvatten

During the 19-century a global warming has been observed, which includes increases in global air and ocean temperatures, widespread melting of ice and snow, and rising global sea level. There is a clear connection between emissions of greenhouse gases caused by the human and the increase in temperature. Climatic changes caused by global warming can be stopped trough decreased emission of fossil fuels, for example by an increased use of biogas. Biogas is a renewable energy source which is produced through anaerobic (oxygen free) digestion of organic material. The gas is a mixture of methane (CH4) and carbon dioxide (CO2) and can be among others used as fuel in vehicles.

Skadliga nollflödespunkter i Fortum Värmes fjärrvärmenät i Stockholm : En analys av dess förekomst och effekter

When several production units provide a district heating network, water is pumped from different directions. When the flows from the plants finally meet in the network, the water can be completely still. These places are called zero flow zones. In district heating networks with several plants, which also have different supply temperatures, large and frequent temperature fluctuations can occur when the zero flow zones move. This may cause wear on the pipes, a phenomenon called low cycle fatigue.For this reason it is important to examine where and when zero flow zones that cause temperature changes occur.

Fiberföstärkning av Limträbalkar

Glulam is a product that was engineered to make use of timber in a more efficient way. Bychoosing timber of similar quality and discarding natural defects during production, thedevelopment of a stronger cross-section is achieved.Carbon fiber is a relatively new material with a high tension capacity. This feature is used toexamine how the bending capacity of the beams improve by adhering carbon fiber laminateson the lower edge of the beamsThe strength of the material is tested with three experiments: carbon fiber on the bottom of thebeam (a), carbon fiber attached to the lower sides of the beam (b) and carbon fiber in thebeam, covered with a layer of wood (c)The results show that the first case, where the carbon fiber is attached to the bottom of thebeam, gave the best result with an increase in capacity of 59 % compared to the nonreinforcedcontrol. The other two cases also show an improvement in capacity, beam-type 3had a capacity increase of 47% and beam-type 4 increased with 25 %Tests were also made with glulam beams reinforced with fiberglass, but these tests were notanalyzed in depth because the purpose was to compare the capacity to carbon fiber. Thisbeam improved its capacity by 40.3%.The tests show that carbon fiber as a reinforcement material for glulam is a good choice whenthere is a requirement for stronger cross-sections in both new production and renovation ofold buildings.

Klövviltets nyttjande av foderraps på viltåker och betespåverkan på angränsande skog

Today we have more game species than ever before in our landscape, both regarding number of species and number of individuals. The increasing number of wild species is an increase in game recourse for the countryside. The increase of game species, however, has negative effects on forests and agriculture land. The negative effects for forestry are damages on economic important trees, due to losses in production and quality. However there are ways to decrease the damage on valuable and important trees.

Utvärdering av en beslutsåterkopplad kanalestimator för tredje generationens mobiltelefonisystem

This Masters thesis work describes a comparison between two different methods for estimation of the down channel (base station to mobile subscriber) in Wide-band Code Division Multiple Access (WCDMA). The first estimation method, Optimal Feed-forward Channel Estimation (OFCE), is a conventional method that bases the estimates on data that is known to both sender and receiver, so called pilots. The second method, Decision Directed Channel Estimation (DDCE), is an elaboration of OFCE. It also uses user data for estimation. Simulations show that DDCE, in comparison to OFCE, does not attain an improvement in signal-to-noise-ratio (SNR) for high bit error rates (BER).

Naturvärden i en värmländsk bruksskog : en skogshistorisk studie av Åbengtshöjden/Bogranghöjden

In this study I have analysed the history of a forest belonging to Saxåhyttan in Värmland. The study area is 448 hectares and has been used by iron industry since the 16th century. A forest that has been used by man during at least 400 years should have few ecological values. This inventory however shows the opposite. The aim of the study is to interpret the history of the forest in the area, i. e.

Competition for forest fuels in Sweden : exploring the possibilities of modeling forest fuel markets in a regional partial equilibrium framework

This thesis project focuses on the need for better tools for analyzing competition for forest fuels in Sweden, in particular how policy measures may influence the market and involved actors in different regions of Sweden. Raw materials from the forest have for long constituted important inputs in the Swedish forest industry. Today some of these raw materials are increasingly used as inputs also in bioenergy production, largely driven by bioenergy promoting policies, and there are signs of increased competition for forest fuels which may have various and uncertain effects on the industries in question. The thesis project explores the possibilities to adapt previously used forest sector equilibrium models into a new model suitable for analysis of Swedish forest fuel markets, called the Swedish Forest Sector Trade Model (SFSTM). The approach takes into account regional differences in supply and demand for 23 types of products produced and/or used by eight types of producers, plus consumers, in five different regions (four Swedish and one international).

Tubular polyethylene biogas digesters : development and testing of a biogas technology in Malawi to reduce deforestation and support climate change mitigation and adaptation

The aim of the study was to install a biogas system consisting of three tubular polyethylene biogas digesters at a rural household in Malawi and to evaluate the constructed biogas system with regards to relevant system parameters. The purpose was to evaluate if the technology is a possible solution to reduce deforestation and support Malawi in climate change mitigation and adaptation. The study was carried out in the southern part of Malawi in cooperation with the University of Malawi. Locally available materials were used to construct and install the system. Three different feed materials, cow, goat and a mix of cow and goat manure, were used in order to determine which one was best suited to utilise as a digester substrate. After the installation, measurements of temperature, pH, biogas production, biogas composition and system functionality were made. The results of the study show that a biogas system with tubular polyethylene biogas digesters can be successfully installed at a rural household and that the most suitable feed material is a mix of cow and goat manure.

Analys av planering inom byggproduktion. Hur kan förbättring ske med hjälp av slututvärdering och återkoppling?

A clean and affordable energy source for cooking is deficient in developing countries. People rely on fuels that contribute to environmental, social and health problems.Biogas is an alternative energy source and an increased investment in small-scale biogas production can in several developing countries be found. Several projects have started to use the technology in developing countries because of the benefits with biogas. Some cases in the establishment of biogas plants have succeeded and some have not. The study is a literature review supplemented by two field studies.

Villkorad av verkligheten - Om produktionen av Arbetsförmedlingens yrkesbeskrivningar

The first aim of this study is to describe how the public employment service (PES) producesoccupational descriptions. The second aim is to analyse the conditions for that production.Method: The empiric material consists of seven qualitative interviews with employed at PES,operational plan for the team working with descriptions on occupations and observation notes.The overall theme in the study is Foucaults perspective on power. The conditions forproduction of occupational descriptions are understood in the light of the governmentality perspectiveand the concept of employability. Bourdieu´s concept habitus, symbolic violence and capital are usedto articulate the officials? values and experiences.Eight officials at PES produce the occupational descriptions.

Produktionseffektivisering : - Få processens samtliga aktörer att sträva mot samma mål genom ökat samarbete och delaktighet i produktionens olika skeenden.

The productiontime in the construction industry contains of many different participants which will take part in different events. When there is so many people working with the same project it is easy tosee one self just as a part of the game. The consequence of this is that they don?t see themselves as important participants whos knowledge, opinions and experience can be useful in the whole production process. This might lead to that they feel neglected and the consequence of that will be lackof motivation.

Utvärdering av tillgänglighet på Stora Ensos massabruk i Skutskär

Self-driving cars are soon to become a reality to the commercial market. A self-driving car does not have a human operator, which enables some interesting characteristics. The main benefits are considered to be:The number of accidents and traffic jams should be reduced.Enhanced comfort.Energy usage could be decreased while capacity could be increased.This study concerns the causes for improved energy efficiency. The reason for improved energy efficiency is mainly because of the variation in terms of acceleration, braking and distance holding are reduced. The vehicles are more intelligent and can work together as a unity.

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