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75 Uppsatser om Weyl-Lanczos equation - Sida 4 av 5
Statistiska metoder för härledning av indata till säkerhetsanalyser inom kärnkraftsområdet
Objective: In recent years there has been an increasing interest within the clinical (medical) science in measuring people?s health. When estimating quality of life, present practise is to use the EQ-5D questionnaire and an index which weighs the different questions. The question is what happens if the individuals estimate there own health, would it differ from the public preferences? The aim is to make a new prediction model based on the opinion of patients and compare it to the present model based on public preferences.Method: A sample of 362 patients with unstable coronary artery disease from the Frisc II trial, valued their quality of life in the acute phase and after 3, 6 and 12 months.
A foreign aid dilemma : a study of budget support versus project aid
Foreign aid is a very debated and controversial topic. The most recent studies have focused more on GDP growth and foreign aid correlation, however not much of the debate has focused on what kind of foreign aid should be given. The most common foreign aid is budget support, often a bilateral funds transfer between two countries. This kind of foreign aid can be both conditional and unconditional from the donors? perspective.
Klimatsimulering av ett kontorsrum : Hur de termiska stigkrafterna påverkar ventilationseffektiviteten
AbstractIn urban societies people spend more and more time indoors, which put great demands on the indoor environment. If the ventilation is to manage the removal of unwanted substances in the indoor air, a good mixing of the air is required. The question arises that, whether the buoyancy forces will counteract a good mixing of the indoor air or not?This report aims to clear up the difficulties whether you need to consider the buoyancy forces or not, when adjusting a ventilation unit. For studying the indoor mixing of the air a two dimensional model is constructed in COMSOL Multiphysics.
ADHD- diagnosen i skolan : En kvalitativ undersökning om fem pedagogers förhållningssätt till diagnosen ADHD i Åk 6-9
ADHD (attention deficit hyperactivity disorder) is a phenomena that is much talked about in both schools and in communities. Today, there is a conflict surrounding the diagnosis ADHD. A part of the conflict takes part between the sociologist Eva Kärfve and Christopher Gillberg, professor in child- and teenage psychology. The roots of this conflict surrounds the much debated line of what is seen as normal and ?too? different, basically how many children that actually should have the diagnosis.
Identifiering av deponerat material i en deponi samt metodikförslag för upprättande av vattenbalans.
Högbytorp is Ragn-Sells? largest waste facility and it is located north of Stockholm. There is an old landfill still in use, but at the end of this year it will be closed. The waste deposited on the landfill can, through decomposition, give rise to a large amount of methane gas, which is an energy rich gas that can be used for heat and electricity production. To receive a relatively large amount of gas, the decomposition requires a high moisture content in the waste.
Temperatursprickor i ung betong : Utvärdering av projektering och utförande av åtgärder, samt utveckling av dimensioneringsmetod för kylsystem
The report contains three parts. The first part is a summary and overall presentation of thermalcracks and preventing measures against such cracks. This is a theoretical part where theinterested designer can get acquainted with various alternatives, be guided to more detailedliterature, and receive some practical information regarding the design of the respectivemeasures.The second part deals with calculation of the risk for thermal cracks and design of water coolingas a limiting measure. Two complementary methods are reviewed for efficient calculation:?the handbook method CraX1(by Lulea University of Technology) is used for quickverification?finite differential analysis in the calculationtool ConTeSt Pro for more precise projectingHere is also presented a development of existing standards through design of the cooling systemby means of the Bernoulli equation.
Konstruktion av current conveyors via makromodellering
A current conveyor is an active building block that can be used to implement most active and passive components. It differs from the operation amplifier in that it uses current instead of voltage. The current conveyor also has significantly higher voltage gain over a broader frequency range. To simplify the construction of analogue circuits and increase the construction efficiency it is desirable to use a top-down methodology. This means that the whole system is partitioned into a hierarchy of subsystems.
Parametriserad 3D-modell av cyklon : Parametrisering av en 3D-modell av ett cyklonfilter i SolidWorks för snabb framtagning av nya konstruktioner till Outotec Skellefteå
This bachelor thesis project has been executed at Outotec Sweden AB in Skellefteå. Outotecs main business focus is selling mineral and metal processing technologies. A rest product from the metal process is particle-polluted gas and cyclone designs are today the most commonly used abatement device for particle control. A cyclone provides a simple design with high efficiency particle percolation by using air streams.The purpose of this work is to reduce the time it takes create new cyclone designs in Outotecs projects. An extensive construction work is needed for every new cyclone order due to new designs.
Beslutsmodell för inköp och lagerhållning av motorer i ett produktionssystem : En fallstudie på Sandvik
AbstractIt is important to choose which spare parts to keep in stock. With the right spareparts in stock the costs for inventory and production loss will decrease. Cavalieri et al. (2008) highlights that the balance between inventory cost and production loss is underestimated. It affects the company and must be considered before decision on purchase.The problem with spare engines is that they are all more or less critical for the production. That can be a reason for why no previous research targeting engines and classification of with engine should be kept in stock has been found.
Underhållskostnader för tröskor :
Costs of maintenance on combines are a subject of interest thus it constitute a large
investment and cost for the individual farmer. Therefore it is important to have up to
date knowledge and the right facts to be able to do reliable calculations on one of the
largest investments for a farmer.
The aim of this study was to compare costs of maintenance on combine/threshingmachine
with the computer program for advising environmental issues in agriculture,
STANK. Interviews took place and data were collected by handing out questionnaires to
20 farmers. A similar study conducted by Neuman (2003) investigated costs of
maintenance and compared these with STANK. The results of this study have also been
compared and examined related to data from SLA - Skogs och
Lantarbetsgivarförbundet.
The result shows that 18 out of 20 combines were given a higher cost of maintenance
when using STANK compared to the numbers in this study.
Konst och exil : En undersökning av Shirin Neshats fotografi och videokonst i relation till exil
The Iranian artist Shirin Neshat has been living in self-imposed exile since the late 1970s, as she chose not to return to her home country following the ?79 Islamic Revolution. Through her works Neshat examines Iran before and after the revolution and follows political and civil transformations through strong photographs of women in her country of birth. My own use of the term exile deals with the analysis of the state of exile in relation to artistic work as a globalized and underlying motivation for art and artists. The new definition of exile is analyzed in relation with the artist?s photographs and the verbal and visual statements.
OTEC för Tarawa
Ocean Thermal Energy Conversion, OTEC, a technology using the temperature difference between cold deep seawater and warm surface water, can extract the work in the form of electricity. OTEC gives also synergies of drinkable fresh water. The temperature difference has an impact on the efficiency of the technology, which means that the feasibility of OTEC is geographically limited. The project intends to explore the possibility of replacing the atoll Tarawa?s present electricity generation with an OTEC plant and to explore synergies. In the present situation all of Tarawa?s electricity is generated by fossil fuels.
Drainfill
Ocean Thermal Energy Conversion, OTEC, a technology using the temperature difference between cold deep seawater and warm surface water, can extract the work in the form of electricity. OTEC gives also synergies of drinkable fresh water. The temperature difference has an impact on the efficiency of the technology, which means that the feasibility of OTEC is geographically limited. The project intends to explore the possibility of replacing the atoll Tarawa?s present electricity generation with an OTEC plant and to explore synergies. In the present situation all of Tarawa?s electricity is generated by fossil fuels.
Analys av turbulensmodeller för CFD
This thesis has been a part of Forsmarks Kraftgrupp AB's evaluation of a turbulencemodel used in simulation of turbulent flow called PRNS (Partially Resolved NumericalSimulation). This model has promising properties and may be of use in savingcomputational resources. The purpose of this thesis was to analyze this model andcompare it with industrially applied models such as k-omega SST and LES (Large EddySimulations).PRNS works as a hybrid of the k-omega SST and DNS (Direct Numerical Simulation)where a constant, RCP (Resolution Control Parameter) with a value between 0 and 1are selected. This constant is then used in the calculations and determines thebehavior of the simulation. When RCP is set to zero the equation are the same as fora DNS simulation and when RCP is set to one the equations for k-omega SST issolved.
Transporttider för vatten i närområdet till en vattentäkt : spårämnesförsök i en isälvsavlagring
When establishing a groundwater protection area it is of great interest to be able to estimate the transit time of the groundwater from different places of the aquifer to the withdrawal well. These estimates can be uncertain due to heterogeneities in the aquifer. As a part of the work to develop methods for a more certain delineation of protection areas, a tracer test was performed in an esker located 25 kilometres NW of the town Uppsala.The purpose of this master thesis was to perform, describe and evaluate the tracer test. Travel times from the tracer test should then enable comparison against stochastic simulated travel times of the groundwater in the area.Three dyes (rhodamine WT, uranine and naphtionate) and a salt (NaBr) were used in the tracer test. The tracers were injected in four different wells located 25 meters from a pumping well.