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436 Uppsatser om Biomass losses - Sida 16 av 30
Privata skogsägares inställning till frivilliga naturvårdsavsättningar samt kvalitets- och tillväxthöjande skogsskötselåtgärder :
The business mission of Norra Skogsägarna is to achieve a profitable forestry for the private forest owners. With this as a background it is of interest for the forest owner association to know how forest owners think about voluntary retentions, the methods of increasing production and quality and if there are differences between those who have chosen to certify their forest and those who haven?t. This kind of knowledge is of importance, to in an effectively and adjusted way, help the forest owners achieve a profitable forestry.
The objective of this master thesis is to increase knowledge about private forest owners? opinions of the methods of increasing production and quality and to what extent these methods are used.
Studie av värmeflöden i befintligt bostadsbestånd : Utvärdering av energieffektiva besparingsåtgärder
The purpose of this master thesis is to investigate different types of measures for making buildings more energy efficient and to estimate their profitability. The calculations were performed with the building simulation program VIP+ and the evaluation of the profitability with the life cycle cost method. Furthermore, it was examined how losses in the distribution of secondary systems of district heating can be avoided. Options to replace district heating with a local district heating system based on bio-energy have been investigated. The possibilities of achieving more efficient thermal energy consumption and production for the chosen estate were also examined.The object of the study has been a residential estate with 133 detached houses in Uppsala, built in 1974.
Alternativ till fortsatt elektrisk generering i Olidan
In this thesis a possible cost effective runner change of some of the units in the hydroelectric power station Olidan is investigated. The possibility to drive a unit at the same efficiency point through a change of the turbine shaft speed and the rate of discharge is tested. Furthermore the theories behind model testing, determination of efficiency increase from model to prototype and efficiency measurements shall be discussed and analyzed with Olidan as a starting point.A predicted curve has been built on information from model tests and field measurements on the existing runners and runner data from the test of the new model. The predicted curve shows the difference in efficiency between an existing runner and a modern one. It is the difference in efficiency that is used in the calculations that are to show whether changing to a pair of new runners will be cost effective or not.
Krafter på rörsystem vid transient flöde : En jämförelse mellan RELAP5 och Fluent
At Forsmarks Kraftgrupp AB (FKA) forces on pipe systems due to transient flow are frequently calculated as a step to verify their structural integrity. In nuclear industries these forces are often calculated with a one dimensional thermal-hydraulic analysis-code called RELAP5. When calculations regarding more complex geometries are needed, the three dimensional code Fluent is often used. This code is highly time consuming and requires large computational power.This projects aim is to compare calculations of pressure, flow and forces carried out by RELAP5 and Fluent for an arbitrary pipe section during transient flow conditions. This has been accomplished by constructing a simple geometry for which a transient flow is simulated in both programs.
Ensam är stark? : En kvalitativ studie om efterlevande personers erfarenheter av omgivningens stöd i samband med en förlust och av att ha delagit i en sorggrupp
The aim of this qualitative study was to examine bereaved individuals? experiences of support from their social networks and participation in support groups. The theoretical framework is based on theories about social support and parts of the attachment theory. Data were collected from four interviews and analysed by the study?s theoretical framework.
Utveckling och applicering av en aviditets-ELISA för bovint respiratoriskt syncytialt virus :
Bovine Respiratory Syncytial Virus (BRSV) is a common cause of respiratory disease among young cattle. The virus causes severe losses; the herd mortality rate can sometimes be as high as 20 %. In this study the avidity (i.e the antigen binding force) of BRSV specific antibodies was measured to see if there was a difference between antibodies produced during an acute phase of infection and antibodies produced by earlier infected animals.
A commercially available ELISA-testkit against BRSV-specific antibodies was used and an incubation step with 6M urea was added. The effect of the urea is that it breaks the weak bonds between antibodies and antigen while the stronger bonds remain intact.
Four different groups of animals were included in this study; seven calves that were naturally infected, three acutely infected calves with known time of infection, five cows that were seropositive during several years and four experimentally infected calves that had been a part of a vaccine trial.
The results of this study showed that antibodies produced during the acute phase of an infection had a low avidity and that the avidity increased with time after infection.
Bilden som kommunikationsverktyg
Transportation of pigs might be a welfare problem. Stress during and after transportation can negatively affect the meat quality or cause carcass damages, which leads to major economic losses every year. The transportation chain can be divided into several stages; loading, transport and unloading. This literature review focuses on unloading of pigs from a transport. When arriving at an abattoir pigs can be fatigued and need to be as smoothly unloaded as possible.
Bioenergy from the forest ? a source of conflict between forestry and nature conservation? : an analysis of key actor?s positions in Sweden
Bioenergy from the forest has been heavily debated in Sweden for several decades due to the interest of society to decrease dependence upon fossil fuels and limit the effects of climate change. The actual use of bioenergy from the forest has shifted over the years but increased during the last decades. Private actors within forest and nature conservation sectors play an important role for the development of bioenergy from the forest as well as for the debate and the implementation of political goals. Forestry in Sweden is characterised by ?freedom under responsibility? for private actors and the perspective of governance is valuable for studying actors and discourses.
Factors influencing pig behaviour during unloading from a transport
Transportation of pigs might be a welfare problem. Stress during and after transportation can negatively affect the meat quality or cause carcass damages, which leads to major economic losses every year. The transportation chain can be divided into several stages; loading, transport and unloading. This literature review focuses on unloading of pigs from a transport. When arriving at an abattoir pigs can be fatigued and need to be as smoothly unloaded as possible.
Magasin för lagring av vatten och växtnäring
Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.
Solvärme med säsongslager i Lyckebo
The purpose of this thesis is to investigate and clarify the facts surrounding one of Vattenfall's district heating plants; The "solar field" and associated rock cavern in Lyckebo, Storvreta. The plant was built in the '80s by the formerly municipal utility,Uppsalakraftvärme AB, as an experimental building. A ground water filled cavern would serve as seasonal storage of solar heat from an adjacent solar field. Since both the energy company and the facility itself has undergone major changes over the past 30 years, there was a great need to gather facts in order to provide a picture of its current condition and potential for continued use. The thesis investigates the plant's history and problems with the rock cavern losses, and how the operation developed. It also presents the calculations regarding the possibilities of again supplementing the facility with solar energy - which is not the case today - as well as the economic conditions for it. Regarding a re-launch of solar energy, primarily a concentrating solar collector has been studied, as it has the advantages of an integrated control system.
Corynebacterium pseudotuberculosis hos alpacka : utredning av ett utbrott i en svensk alpackabesättning
The alpaca is a camelid that originate from the South American highland. During recent years it?s been possible to keep alpacas in other parts of the world. Today there is a world-wide interest in alpacas, but there is still limited knowledge about this fascinating animal. There are approximately 350-400 alpacas in Sweden in 2007.
Validation of a tetraplex assay for detection of antibodies in poultry serum using Luminex 200 platform.
Background: As a part of a national health control program, Statens VeterinärmedicinskaAnstalt performs diagnostics to screen flocks for certain pathogens causing high mortality,morbidity and/or serious economical losses. There are several viruses in the programincluding IBDV (infectious bursal disease virus), IBV (infectious bronchitis virus) and NDV(Newcastle disease virus). Method: 96 serum samples were collected from different poultryflocks in Sweden and analyzed by ELISA, which are currently used in the health controlprogram as well as by a commercial prototype of a multiplex immunoassay manufactured byLuminex Corp., which is currently under evaluation at the United States Department ofAgriculture USDA. This 4-plex assay detects antibodies for the three above-mentionedviruses as well as antibodies of avian reovirus. In the context of this study the ELISAs run inroutine diagnostics as well as a REO ELISA were used as the standard for comparison.Result: The antibody concentration in serum from vaccinated chickens was high while theantibody concentration level in serum from not vaccinated chickens was low.
Simulering av hydrauliska dämpare i borrslagverk
This master thesis consists of the creation of shock absorber models for percussive rock drills. A model of the rock was also developed. These models were connected to existing models of the rock drill to create a complete simulation of the rock drilling process.When the models had been created the rock model was evaluated by comparison with measured values from lab tests. The verified rock model was then used to evaluate the shock absorber models.Four new shock absorber concepts have been developed. Three of these have been modelled, while the fourth have only been sketched and described.The evaluation of the models showed the following:? Simulations of the single shock absorber don?t correlate to reality very well.
Svampar associerade med raps : betydelse för uppkomst och grödetablering
Oilseed rape is an important crop in Sweden and is grown on about 90000 ha today. The interest in oil seed pro-duction is increasing because of growing demand and high prices for oil seed both in Sweden and Europe. However, an increased intensity in the oil seed production can bring higher risk of yield losses due to fungal diseases. The purpose of this study was to investigate what different fungi are associated with oilseed rape under field conditions and if their incidence is correlated to crop establishment problems.
This study was carried out in three parts: 1) investigations on fungal community structure in roots and rhizosphere soils from young spring- and winter rape plants sampled in failed respectively good establishment patches in four fields, 2) investigations on the pathogenicity of fungi isolated from oilseed rape in controlled environment and 3) investigations on the effect of different fungicide seed treatments on germination and early plant development in a field soil naturally infested with damping off- and Verticillium wilt pathogens.
The studies on community structure using a combined approach of standard fungal isolation techniques and DNA based methods revealed a high fungal diversity in three out of four studied fields of spring rape and winter rape. For some unknown reason, very few fungal species were identified from the fourth field.