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970 Uppsatser om Emission rights - Sida 28 av 65
Utveckling av en Multi-Zonsmodell för NOx Bildning i Diesel Motorer
This thesis work is the last part of the Master of Science education inmechanical engineering at KTH, Stockholm.The aim of this project was the development of a Multi-zone modelfor NOxformation in Diesel engines. Because of the stringent emissionlegislations, great effort is made to decrease the fuel consumption and theharmful emissions of internal combustion engines. Computer simulationsplay a decisive role in this context because they substitute the expensiveand time-consuming laboratory tests.The model is based on a multi-zone approach and uses the wellknownExtended Zeldovich Mechanism which gives a relation to calculatethe NO formation rate using the concentration of different gas speciesinvolved in the process.All the most important phenomena involved in the Diesel combustionhave been modelled. A special attention is then paid to the equilibriumconcentration calculation; this is a significant part of the model whichstrongly influences the following steps.A Simulink model has also been developed. This second version isbased on the previous model and it is made especially to allow theconnection with other external softwares, GT-power in this case.
Vilka faktorer avgör överlevnaden för sågverksindustrin i Arvidsjaursområdet ?
Skogen är den viktigaste exportvaran för Svensk ekonomi. I de norra delarna av Sverige har många sågverk tvingats att lägga ned sin verksamhet det senaste decenniet. Vi har undersökt de tre kvarvarande sågverken i Arvidsjaursområdet, för att se vilka faktorer som har gjort att de överlevt. Vi har använt oss av Property-Rights-teorin vars ena grundtes framhåller att ?om inte jag utnyttjar resursen kommer någon annan att göra det utan hänsyn till mig?.
Invadörer på svenska spelmarknaden-En statligt reglerad marknads ökade konkurrens från webbaserade företag
In Sweden we have a regulated gambling market which means that there are three gambling companies who are operating under the supervision of the Swedish state. These companies have exclusive rights to the Swedish market, divided between them. AB Svenska Spel is one of them and they control all gambling concerning sporting events and the four casinos in Stockholm, Gothenburg, Malmö and Sundsvall. However, since a few years back several Internet-based companies have entered the Swedish market and the competition has become even fiercer in the last years. Due to numerous marketing restrictions the Internet companies have been forced to find new ways to strengthen their brand.
Miljöarbete inom den civila luftfarten
The main environmental problem for aviation is the great amount of exhaust gases, mainly nitrogen oxides, carbon monoxide, carbon dioxide and hydrocarbons - mostly "greenhouse gases" leading to climate changes. I decided to sort out what is being done to decrease these problems and what regulations there are concerning air pollution by the means of searching the internet and using publications from aviation authorities for current figures. I chose to scrutinize authorities on political, authority and company level, resulting in summarizing the work of UN and EU respectively, ICAO (International Civil Aviation Organization), JAA (Joint Aviation Authorities) and LFV (Swedish Civil Aviation Authority), and finally SAS, representing the airline companies. Conclusion that I have drawn are thatthere are regulations for air pollution, written down in ICAO's Annex 16, that are to be followed. Secondly, LFV are environmentally controlling their nineteen airports and since economy is an important reason for not giving priority to environmental issues in aviation emission charge and noise charge are added to the landing fees.
Studier av nitreringskinetiken för järn-kromlegeringar i
ammoniak-vätgasmiljö
Kinetiken för nitrering av en järn-kromlegering med en gasblandning av ammoniak och vätgas har studerats vid temperaturer mellan 500°C och 600°C. För ett gasatomiserat pulver (Fe-7%Cr) har inverkan av syrepotential (H2O/ H2) och olika förbehandlingar (förreduktion och förnitrering) studerats med hjälp av en termogravimetrisk metod. Dessutom har laserablering som förbehandlingsmetod för nitrering av solida ytor studerats med hjälp av GD-OES-analys (Glow Discharge Optical Emission Spectrometry). Resultaten har diskuterats och tolkats med avseende på faktorer som kan påverka ytreaktionens hastighet, kärnbildningsförhållanden samt diffusionsvillkor. Syrepotentialen har visats påverka nitreringshastigheten via komplicerade samband mellan syrepotentialens storlek, kvävehalt i materialet och nitreringstemperatur.
Studie av belagda kolvringarmot plasmasprutat cylinderfoder : Med avseende på friktion och nötningsmotstånd
Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.
Mjölkureahalten som mått på vommikrobernas kväveförsörjning och kons miljöbelastning
The aim of this literature study was to analyze how milk urea concentration is working as a measure of the nitrogen supply to rumen microbes and indicator of the environmental load. Questions included in this literature study were how to improve the dairy cattle nitrogen efficiency and what correlations there are between milk urea, nitrogen efficiency and crude protein content in the feed. Effects on the reproduction from high ration protein content are also addressed. Dairy cattle are today fed with large proportions of protein which could lead to high expenditure of feed and environmental pollutions. The nitrogen can be lost to the environment by different pathways; leaching, denitrification or by emission to the air.
Mjölkureahalten som mått på vom-mikrobernas kväveförsörjning och kons miljöbelastning
The aim of this literature study was to analyze how milk urea concentration is working as a measure of the nitrogen supply to rumen microbes and indicator of the environmental load. Questions included in this literature study were how to improve the dairy cattle nitrogen efficiency and what correlations there are between milk urea, nitrogen efficiency and crude protein content in the feed. Effects on the reproduction from high ration protein content are also addressed. Dairy cattle are today fed with large proportions of protein which could lead to high expenditure of feed and environmental pollutions. The nitrogen can be lost to the environment by different pathways; leaching, denitrification or by emission to the air.
Utvärdering av effektstyrningssystemet EnergiDirigent® ur ett miljöperspektiv
Energy Director is a control and measuring system for energy consumption and is part of the product portfolio of E.ON AG for more efficient use of energy, offered to business customers. As of today, the system has only one parameter of control, namely power, and the objective of this essay has been to investigate whether other ones could be added. The emphasis is on the environmental perspective, which is why carbon dioxide has served as an example for this parameter in question.Parallel with the study of Energy Director electricity on the margin, calculations of carbon dioxide equivalents and also the Swedish trade of electricity have all been highlighted. Results indicate that when reductions in energy are made it is endorsed to omit from electricity on the margin rather than some mean distributed electricity, under certain conditions, and in addition the calculations of the reductions should be modified regarding the efficiency of the power stations fuelled by lignite and bituminous coal. Sweden practices trade with the Nordic countries as well as Poland and Germany.
Kväveförluster och energianvändning på mjölkgårdar i västra Sverige :
Protecting the environment has with time grown to take a more central role in the society.
Agriculture plays an important role in the society since this sector produces our food. More
thorough research on how agriculture affects the environment is therefore motivated. This
research can be used to improve the agricultural practice from an environmental point of view.
This is something that both the farmers and the consumers can profit from.
This study aims to form the basis for creating environmental indicators for use of nitrogen and
energy on dairy farms. Twenty-three farmers in western Sweden have been interviewed about
their farms, both organic and conventional. They produce milk with different intensity, defined
as the amount of milk delivered (sold) per hectare of arable land.
En Fallstudie av Implementeringen av EU:s Minoritetsskydd
The intention of this thesis in political science is to understand how the European Union fights and prevents discrimination against the Roma minorities in Sweden and Romania, and how the implementation works in reality. The study consists of defining what it means to be objectively discriminated, what ethnicity really means and how the implementation process consist of a comparison and statement has been made by the national governments and comparing how two socioeconomically different member states handle EU directives and implement them in Sweden and Romania. The main findings of this study was that EU policies lack the capital and explicitness that is needed for great results to be accomplished and that the governments in both countries have different issues with implementing the protection of the human rights and Roma culture, and that EU needs to be more practical and develop in a faster pace. .
Värdegrunden i praktiken ? Lärarupplevelser
The purpose of this thesis is to carry out a qualitative study of the perceptions of language teachers as to their role in the teaching of values and morals to pupils. Five language teachers have been interviewed about their perceptions of how values are taught and their role therein. The interviews serve to investigate the reality of teaching values to pupils in a Swedish secondary school and the work involved in this on-going process, this being with a view to having a better understanding of just how important a role the teaching of values plays in the daily working life of a teacher. Terms such as fundamental values and morals can be difficult to define as they are highly personal and can differ from person to person depending on one?s background, experiences and family circumstances, for example.
Fysisk planering ur ett folkhälsoperspektiv ? fallstudie i Hjo
Hur samverkar de nationella folkhälsomålen med fysisk planering, och på vilket sätt kan folkhälsomålen beaktas för att förbättra förutsättningarna för ökad fysisk aktivitet hos barn? Denna studie är en fallstudie i Hjo kommun. Studien tar utgångspunkt i kommunens folkhälsoproblematik som visar att det finns en hög förekomst av övervikt hos barn. Intentionen är att undersöka vilka organisatoriska processer som kan underbygga det kommunala arbetet med folkhälsomålen, liksom att ta reda på vilka faktorer i den fysiska miljön som skapar förutsättningar för barns fysiska aktivitet. Avsikten med studien har varit att skapa ett underlag för Hjo kommuns översiktliga planering.
Khmer Rougetribunalen - Integritet i personalrekryteringsprocessen för säkerställande av ansvarsutkrävandets syften
The communist party Khmer Rouge took over the power in Cambodia in 1975, and ruled the country until the beginning of 1979. During these years they attempted to create a completely new society, a true Khmer nation, which involved massive economic and social reorganisation and elimination of people which did not fit in the new ideal.Three decades has passed since the genocide, and the senior leaders of the Khmer Rouge will now be tried in the Khmer Rouge tribunal, which consists of both Cambodian and international judges and prosecutors. The integrity of those tribunal representatives will be crucial for the integrity of the tribunal as a whole and thus also for the outcome of the processes. It is hard to determine whether the purposes for demand of accountability will be satisfied, it is though clear that there are many obstacles in the way for an unproblematic and fair procedure..
Individualiseringens dilemma : Hur uppnås ett fungerande samspel mellan individualisering och gemensam undervisning i matematik?
Abstract.The levels of dioxin and comparable substances rose to a large extent in our environment during the second half of the 20'Th century. This was the result of the synthesis of, and careless usage of these substances in cooling fluids, hydraulics, pesticides etc. Background levels of dioxins and furans in sealed samples prior to this era suggest that former sources of these substances existed. Salt glazing is a method of adding a smooth acid resistant exterior to stoneware ceramics. The technique has been in use since the 16'Th century, maybe even earlier than that.