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11505 Uppsatser om Access-based consumption - Sida 22 av 767

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.

The pros and cons with technology sourcing: A case study of sourcing contracts in the Contract Research &Technology Market

Purpose: The purpose of this thesis is to analyse the process of technology sourcing within firms active in the CRT-market. The primary focus of the study is the motives, risks and problems associated with technology sourcing, to construct key learnings for organisations consider undertaking this way to access research and development or those organisations that are already operating in the CRTmarket. Method: As method has abduction been used. The empiric material of the thesis is based on qualitative research in form of interviews in a conversational manner. For correct interpretation and understanding a hermeneutics approach has been used.

Effects of shade on milk production in Swedish dairy cows on pasture

Heat stress negatively influences the performance of dairy cattle such as lactation and reproduction. Heat stress can cause production losses as well as welfare problems. Years of research have shown that heat stress is a huge problem for dairy cattle in both the tropics and temperate zones but no such research have so far been done in northern European countries. It seems like shade is an important tool when improving pasture conditions and therefore deserves more attention. The aim with this study was to investigate whether there is a need of providing shade for grazing dairy cows during the summer in Sweden. Two groups of lactating Swedish Red dairy cows (n=15 per group) were kept on pasture.

Oljetemperaturens inverkan på motoroljans degradering i lastbil

The market for heavy duty engines is constantly requiring engines that should be more andmore powerful, while still maintaining low fuel consumption. As a result of increasing enginepower, the engine and coolant temperature increases as well due to insufficient coolingperformance (because of design issues, cost etc.).Also, emission legislations, both current and future, require more and more measures to betaken by engine manufacturers. One way of meeting the legislations is the use of cooled EGR(Exhaust Gas Recirculation), which also lead to increased coolant temperatures.Both these factors also naturally lead to increased engine oil temperatures, the consequencesof which are not thoroughly investigated.This thesis project aims to investigate effects of high temperatures on engine oil degradation,with focus on the greatest degradation process: oxidation. To do this several engine runs havebeen performed on a 310 hp engine with EGR to see what happens to the engine oil in a realengine when exposed to high temperatures. During the tests oil samples have been taken andanalysed for important parameters.As a complement to these engine tests some laboratory oxidation testing have also beenperformed, to be able to compare engine test data with laboratory tests.One goal of the project was to try to formulate an empirical oxidation model, which would beable to predict oil oxidation levels in an engine, given any running parameters.

P?minnelse: Barnen beh?ver extrakl?der och en dubbel upps?ttning ytterkl?der : Att leva med knapp ekonomi i en f?rskolekontext

Families with limited financial resources risk social exclusion in today?s consumption-based society, where status and identity are tied to items like clothing, gifts and activities. Limited financial resources can therefore often lead to social isolation because consumption is central to social participation, something that can rarely be prioritized in poor families. In preschool, unclear policies on extra costs can negatively affect families. The purpose of the study was to investigate how socioeconomically vulnerable families experience and are affected by the preschool and its requirements, as well as how preschool teachers work to reduce the economic gap among families in the preschool context.

Systemidentifiering och reglering av en luftningsbassäng på ett reningsverk

A wastewater treatment plant has the task to refine the wastewater from substances that should not be released into the environment. The decomposition process can, in a simple way, be described as follows: micro-organisms breathe oxygen and eat unwanted substances. The environment in which the micro-organism lives is known as sludge and the correct amount of oxygen available in the sludge is important for the decomposition to be effective. The oxygenation of the sludge alone stands for about 30% of the plant?s energy consumption.

En energiutredning och miljöklassning av Hemsta 12:16

The purpose of this study was to implement an energy analysis and environmental evaluation of the property Hemsta 12:16 in Gävle. Based on two different methods, Energy Balance calculation and Environmental Building, the result of the property's energy use, energy performance and environmental impacts are presented. Except that, measures to reduce final energy consumption are presented.      The proposed measures can reduce energy usage by 100 400 kWh / year, which represents a decrease of 18% of the present energy usage. This would represent a total savings of 63 000 SEK per year. In addition, the environmental performance is improved by adopting the suggested measures..

En smak av svensk manlighet : Ideal och värden i sportdrycksreklam

The society of consumption exposes us to a lot of information, where advertisement constitutes an extensive part. Due to its expanding, advertisement receives a natural and obvious space in our everyday life. This study aims to investigate how social and cultural values can be mediated in advertisement. The focus has been put to ideas related to health and fitness in the advertisement of power drinks. The thesis takes social constructionism as a starting point, and combines image- and critical discourse analysis in purpose to analyze the pictures.Sociology of consumption, construction of identity, lifestyle and everyday life all constitute an essential part of my analysis.

Slitundersökning för jordbearbetning och sådd :

In this study we try to focus on the costs for wear parts on different type of soil tillage machines and at Väderstad Rapid drilling machine. We have studied some of the leading types of cultivators and disk harrows. Among the cultivators we have investigated Väderstad Cultus, Dalbo Dinkomax, Horsch Tiger and Terrano. At disk harrow we have looked at Amazone Catros and Väderstad Carrier. We have made more detailed study on costs for wear parts, working depth, driving speed and diesel consumption.

Rening av avloppsvatten med anaerob membranbioreaktor och omvänd osmos

This master's theses was carried out on assignment from Stockholm Vatten AB as a part of a project developing new waste water treatment techniques. The goal of the theisis has been to evaluate an anaerobic membrane bioreactor for treatment of waste water from Hammarby Sjöstad. The bioreactor has not been heated and the main interest has been to study the gas production, power consumption and the reduction of organic matter and nutrients.The system has been completed with a reverse osmosis unit and a total of four batch runs have been made with good results. The use of reverse osmosis allows nutrient in the waste water to be reintroduced into circulation as the reverse osmosis concentrate can be used as crop nutrient.The membrane unit is of VSEP ("Vibratory Shear Enhanced Processing") type and an extensive membrane test has been conducted. This so called L-test helped determine the most suitable type of membrane for the system to allow a higher ±ux and thus lower power consumption.

Åtgärdsförslag och känslighetsanalys vid energieffektivisering ur ett fuktsäkert perspektiv : En fallstudie på timmerhuset Sofiedals herrgård

This thesis investigated the possibilities to resume cultivation of an old manor house built of timber and what this would mean from an energy and moisture perspective. The building in this case study is named Sofiedals mansion and was built in 1858 in Valbo 11 kilometers west of Gävle.The structure of the house was documented and used as a starting-point for carrying out calculations focused on energy and moisture aspects. With the help of a number of computer programs and a conducted air tightness test, the buildings energy consumption were calculated and compared with the current building regulations.In addition, the building was analyzed considering energy retrofitting and what it meant for moisture problems. The energy retrofitting consisted of additional insulation, decreasing the buildings permeability through air sealing; window and door replacements. When a building is equipped with natural ventilation it is difficult to know its precise performance and how an energy retrofitting affects it.

Kristen i det senmoderna : Unga frikyrkligas identitet i senmoderniteten

The purpose of this essay is to examine how young members of Free Churches relate to issues connected with lifestyle and identity, based on the changed conditions for the self in late modernity. More specifically, I want to examine how they deal with the increased degree of detraditionalisation and institutional individualization in late modernity.My research-question is:How do young members of Free Churches relate to issues connected with lifestyle and identity, with the increased degree of personal freedom and institutional individualization in late modernity as a starting point?The empiric part of the essay is carried out by qualitative in-depth interviews with five young members of Free Churches. These semi-structured interviews are focused on a number of different areas of the changed conditions for the self in late modernity.My theoretical perspective has been constructed from the theories of Anthony Giddens, Zygmunt Bauman, Ulrich Beck and Elisabeth Beck-Gernsheim. From these theories a focus on certain relevant areas of the condition of the self in late modernity, has developed.

PARS PRO TOTO? Tillgång till Internet som en del av tillgängligheten på sex folkbibliotek

Internet access has been a part of the range in public libraries for approximately a decade. The Swedish municipals, in charge of the public libraries, and the libraries themselves, have a great deal of saying in how they should be run, what to offer the public, how many hours they have to stay open etcetera. The Library law is very vague on many things, including public Internet access. Even though Sweden is ranked as first runner up worldwide when it comes to Internet penetration among the population (Internet World Stats 2007), approximately twenty percent in the 16-74 age group does not have Internet access at home, at work or at school (SCB 2006a). In this master thesis we try to determine, through personal interviews, how six of those in charge feel about Internet at their libraries, all located in medium-sized municipals (20 000 ? 40 000 inhabitants), why they have chosen the rules and regulations they have and their thoughts about what they consider to be the most important assignment of public libraries.

The school as an arena for alcohol prevention : A study on how alcohol prevention / promotion can be carried out in upper level of compulsory school

The consumption of alcohol has stabilized in Sweden 2007, after several years of high increase. Despite the stabilization of the consumption the avaliability of alcohol has been raising, which constitute a big and in future years likely an increased risk in health among young people. The aim of the study was to describe how the staff on a secondary school works among pupils with alcohol prevention and promotion. Aquired knowledge are received from litterature, scentific articels and Internet to strength the relevance of the study. The school is an important arena in the work with alcoholprevention among pupils.

Personarkiv på Kungliga biblioteket -ordningar, kopplingar och krockar på ett nationalbibliotek

The departure point of this thesis is the context of the institution and the processes surrounding the handling of personal archives at the National Library of Sweden. These processes are examined using Actor Network Theory. Around the personal archive a network is constructed and contained by actors ? the archive itself, the librarian, the conservator, the researcher, organizational structures and others. Within this network choices are made of what is significant.

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