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957 Uppsatser om Thermal heat losses - Sida 50 av 64
Tillämpning av en markprofilmodell för hydrologiska beräkningar i avrinningsområdesskala
There is a great need to reduce nutrient leaching from arable land into lakes and oceans. By using several different types of models it has previously been possible to describe nutrient losses in a catchment area with a minimum unit of sub-catchment level. At present, it is instead desirable to model a smaller catchment with an opportunity to re-connect the results to the corresponding fields in the catchment. Such models already exist but they are not fully able to properly describe Swedish conditions and land characteristics in our region.With the approach of creating such a model, SLU has developed a project with this work as its first stage. The model is expected to be created under the working name SWE-model which stands for Soil Water Environment and is in this first stage supposed to apply the SOIL model in catchment scale. During the procedure to describe the first step in the process of developing such a model adapted to Swedish conditions and which works in the catchment scale with an area of about 10-30 km2, focus has been set on calculating the transport of water flow from different hydrological response units. Regardless of the processes occurring in the soil after the water has been added, it is assumed that all the water which flows from each simulated unit is drained.In the first step the hydrologic response units were identified based on land use and soil type in the study area. With the help of a script with functions that retrieve and transform data, certain units were chosen for simulation. The script was also created in this project. Finally, the model results were aggregated and summarized for each unique unit, for each sub-catchment, and also for the whole catchment.From the results it is possible to see similarities in the flow dynamics between modeled and measured data. The efficiency coefficient has been calculated to correspond to the mean of the measured values for the whole simulation period. With an automated calibration process the model should be able to perform better. The volume error gives an indication of overestimation from the model..
Lantbruket som energiproducent : tekniska, ekonomiska och miljömässiga förutsättningar för fjärrvärmeproduktion med lokalt skogsbränsle
A third party access to district heating networks has been proposed in Sweden, to increase the competition
on the district heating market. Such third party access could create opportunities for the agricultural sector
as an energy producer. This study describes the technical, economical and environmental prerequisites for a farmer cluster to build and run a heating plant, fueled with local wood fuel.
The heating plant in the described scenario is 8 MW and will supply a village of 1000 houses, and is fueled with wood chips exclusively. Supplying a heating plant with fuel puts high demands on the logistics, since there need to be a continuous flow of fuel. In the scenario, wood residues from felling and thinning is stored in stacks in the forest, and a few times a year chipped and transported to a storage area at the heating plant.
In the study, an estimation of the profitability has been made by estimating the cost of the investment,
personnel, operating and maintenance costs and costs for the fuel and ash handling.
Rekryteringsstrategier inom marknadsföring och kommunikation : En kvalitativ studie avhur individer och organisationer hanterar sökandet efter medarbetare/arbetsgivare och hur rekryterare skapar matchning
This paper describes and analyzes how individuals and organizations that operate in careers in communications and marketing deal with the search for employees / employers, and how recruiting managers and recruitment consultants are working to create a match between the parties. The study was conducted on behalf of a recruitment agency that offers services in recruiting and staffing for organizations in communication and marketing. The empirical material consists of ten qualitative interviews from three different perspectives on the labor market, recruitment consultants, managers and employees. The interviews were analyzed from sociological and social psychological theories of organizations and individuals opportunities and strategies in today's western labor market. Conclusions that emerged are that organizations need for decreased amount of tied assets provides increased need for temporary employments.
Modellering av flisstack
Bioenergi är en stor industri i Sverige och står för en betydande del av energiomsättningen. Bioenergi i form av flis förvaras runt om i landet på hög i väntan på förbränning. Då högarna läggs upp startar olika processer som värmer upp stacken, ofta till temperaturer på 50°C under det första dygnet. En vanlig ansats i litteraturen är att denna temperaturstegring beror på aerob nedbrytning. Arbetet ämnar undersöka om denna uppvärmning endast beror av mikrobiella aktiviteter.
Småskaligt vattenkraftverk i Nyköpingsån
Interest in alternative energies is high in Sweden today, particularly in the agricultural sector. According to the Swedish lantbruksbarometern (2009), almost all respondents consider the use of some form of alternative energy from the farm. While interest in alternative energies is large, attention to the alternative energy straw has fallen and is almost nowhere mentioned in the literature today. Three years ago, in the Lantbruksbarometern nearly 44% of the farmers would be willing to invest in straw as heating system on the farm. How do the farmers decide to invest in alternative energies? With this information a problem is presented for this paper.
Kemin bakom framtidens avgasrening : En studie av ureasönderfall under kvävgasatmosfär
The purpose of this work was to provide a better understanding of urea?s decomposition and byproduct formation in an SCR system on heavy trucks. In my experimental setup with TGA-DSC-FTIR (a combination of two thermal analysis methods and a method for gas phase detection), an FTIR method for urea in the gas phase was developed for the qualitative and quantitative determination of urea and its decomposition products. Chemicals such as urea, biuret, cyanuric acid and melamine of p.a. quality were used in this method development. Beforehand, there was no FTIR method available to detect these substances; hence, the aim of this work was to develop an FTIR method to understand the degradation chain of urea. The combination of TGA and DSC was used for analysis of different samples, where urea, biuret, cyanuric acid and melamine in varying amounts have been weighted in for various experiments in order to study the temperature at which a phase transition or reaction occurs, i.e.
En analys av centralkylan i Slakthusområdet i Stockholm
In Stockholm, Johanneshov the Slaughterhouse area (Slakthusområdet) can be found. A number of companies have gathered there providing the Stockholmers with meat products. This area has a great need for cooling to supply large cold storages. To facilitate this, a central cooling system has been built, supplying the area with effective and safe cooling.The aim of this master thesis study is to give hints to energy efficient and reliable changes that can be put in place at a low marginal cost depending on the future activities in the area. The suggested changes will be presented to the company Bravida (managing the system), which also desires a deeper understanding of the energy flows through the central cooling system.Firstly visiting the site with proper guidance, we have then tried to understand the function of the system including which machines and media that are used.
Bonusregn över svenska storbanker : En studie om belöningssystemens utformande för legitimitet
The current financial crisis has left its mark. It has even hit the major Swedish banks who have shown large losses. The media has not been slow to take note of this, and the constant political debate about the bonus culture has been reinvigorated. Our aim is to find out how the major Swedish banks relate to the publicity and describe how and why senior executives are rewarded, and what strategies banks are using in the design of their reward system to maintain a legitimate behavior, and thus the confidence of its stakeholders.As a starting point to answer our purpose we have used the agency theory that describes our view of how various problems occurs and how incentives can be established in order to get senior executives to act for their owners' interests. Modern theories of reward systems are taken from a variety of authors, these theories give us an insight into how reward systems can be designed in banks.
Funktionell validering av mutation i PUS-1 i en patient med mitokondriell sjukdom
With the climate change issues growing in importance on the social agenda, the field of urban masterplanning is of no exception when it comes to minimizing the carbon footprint in a variety of projects. The aim of this thesis has been to prepare the Carbon Critical Masterplanning tool, a software plugin for carbon dioxide emissions assessment developed by Atkins, to be used in Swedish conditions. The main targets were to improve the areas of the tool associated with energy conversion and renewable energy sources, and to test the tool in a real case. A planned construction of a new campus in Albano, Stockholm was chosen for the pilot study. A 3D model was built in the tool and the carbon footprint was calculated for a variety of combinations for energy supply to the future area.
Laserinkopplingselement För XFEL Laser Heater : Från Idé Till Färdig Produkt I Designstadie
Uppsala University is involved in a large international collaborationto build the Laser heater system for the European Xray Free-electronlaser in Hamburg, Germany. In this thesis I describe a laser incouplingdevice into the vacuum chamber of this laser heater all the way fromthe specifications to a completed design.The laser heater is a very important part of the XFEL and thepart described here is a part of the vacuum system needed to couplean external laser into the electron vacuum system and align it withthe electron bunches in order to heat them. The task was started by studying the literature about the basic theory andthe design of vacuum systems. After this study and collection of ideaswith colleagues I started to prepare different concepts to solve thetask. The ideas can be put into two categories, in one case the couplingmirror is located inside the vacuum chamber and in the second caseoutside.
DFM för Lasersvetsning
The purpose with this thesis was to develop a designguideline which will simplify the development of new products that will be laser welded. The need for this thesis has come forward from the quality problems that Volvo Construction Equipment, Components Division is having with their laser welding manufacturing unit. The reason for the problems emerges from the bad communication between the development unit and the manufacturing unit within the company when the products produced today was developed. This resulted in products that were hard to and in some cases almost impossible to weld. To avoid these problems from occurring again it was needed to gather the experiences within this area and compile it and present in a brief a pedagogical manner. The information for the groundwork of our results has been gathered by interviews of several key persons in Volvo Construction Equipment, Components Division.
Byggnadens andra skepnad : En anpassning för att möta samhällets behov och krav
Population growth leads to an increased need for new buildings, both residential and commercial. The regulations of structural design also changes with time. From a sustainable community perspective it may be profitable if existing buildings, that no longer performs their original function, are reconditioned. Knowledge and understanding of the surroundings of the residence must be available. Regulations regarding accessibility to all has increased.
Kärnkraftens värde i framtiden : en jämförelse med kraftvärmeteknologi från biobränsle
The debate on the future of Nuclear power in Sweden has increased with the discussion on global warming. The uncertainty of fossil fuel- and carbonprices the latest years has aroused considerable interest in Nuclear from power companies, industry and politicians. Nuclear power plants have negligible CO2 emissions and are not directly affected by increased price of emission rights and fossil fuels. The future power production needs to reduce its emissions of greenhouse gases to become sustainable.
The purpose of this study is to examine the value for power producers to have the option to invest in Nuclear power and how a Nuclear power venture would affect future electricity prices. The study uses two methods, a traditional cash flow model and real option analysis, to estimate the value of Nuclear power.
Basel II och fastighetsbranschen - en scenariostudie av de nya kapitaltäckningsreglernas konsekvenser för fastighetsbranschen
Banks carry a great responsibility when it comes to the financial systems in our society. Disturbance in the credit system affects both lender and borrower. All financial institutions must therefore carefully estimate their risk exposure. This assessment enables them to cover themselves from losses with appropriate capital buffers as main guardian. In order to prevent bank crises and also to maintain financial stability in general, new regulations concerning analysis and preventive actions were introduced on the 1st of February 2007.
Stadsklimat/Gatuklimat :
The purpose of this paper is to understand the climate of the street and how it can be modified to better meet the needs of the street and the user groups. At the same time the conditions of the street and its surroundings also has to be taken into account. To accomplish this it is necessary to have a broad knowledge of the climate conditions in the city. Therefore an overview of the climate elements and how these are modified in the built-up areas are given. The part of the paper which deals with the city climate has a global approach to be able to give an as complete picture as possible.