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1338 Uppsatser om Alternative engines - Sida 6 av 90
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.
Lönsam mjölkproduktion : en fallstudie
Ravelsmarks gård have now reached the stage when there are few options for the future. The
options are either a construction of completely new farm buildings or a winding up of the
milk production. Present on the farm today there is 65 dairy cows plus recruitment. 44 cows
stand in long-stalls and 20 cows stand in short-stalls.
The objective of this study was to examine the profitability of a completely new cowshed.
In order to get costs for investments different milking systems and equipment for feedstuff
have been compared. The systems in the investment budget have been chosen on
recommendations from advisers, salesmen and on the basis on what is suitable for the farm.
One system where a so-called mix feeder wagon is used for the roughage seemed to be best
suited for Ravelsmark.
The different prices obtained for the manure well show that there are possibilities to decrease
the investment costs.
Alternativ till obedövad kastrering av smågrisar : - Ur ett ekonomiskt och djurhälsomässigt perspektiv
This degree project aims to evaluate alternative methods to the unanaesthetized castration of piglets. Castration of piglets is performed to prevent the development of boar taint. Boar taint can cause great financial losses for the pig manufacturer. Unanaesthetized castration of piglets is not regarded to be satisfactory from an animal welfare perspective and the procedure will for that reason be outlawed in the near future.Several alternative methods are used in countries all over the world with promising result. The purpose of this study is to evaluate if this methods could be applied in Swedish pig production.A literature study has been combined with interviews; field studies, questionnaires and a small study on male pig production.To be applicable to and applied in Swedish pig production the alternative method must be financially accepted by the manufacturers but also accepted from an animal welfare perspective.Castration is the only way to guarantee a meat free of boar taint.
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.
Optimering av driftläggningar i Fortums nät
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.
Att bli-nomad och att ta?nka skillnad : En underso?kning av Rosi Braidottis feminina feministiska subjektsfiguration
This essay investigates the feminist philosophy of Rosi Braidotti with particular focus on the alternative feminine feminist nomadic subject that she creates. I also introduce Braidotti?s theoretical inspiration from Gilles Deleuze and Luce Irigaray. I argue that Braidotti creates an alternative figuration for feminism through synthesizeing Deleuze?s concept of ?becoming? with Irigaray?s sexual difference-theory.
Hiphop Edu(N)ation : En kvalitativ studie om relationen mellan skapandet av hiphopmusik och ungdomars socialisation samt identitet
The aim of this study is to explore hiphop music as an aspect of youth socialization and the relationship between music creation and identity. The study is conducted through five semi- structured qualitative individual interviews. Our theoretical starting points are Putnam?s (2000) bridging and bonding social capital symbolic interactionism. We also have used a model of learning presented by Fornäs, Lindberg and Sernhedes (1989).
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.
Industriell produktion av loggia - en studie om loggiarum som alternativ till inglasad balkong
AbstractIntense competition in the building industry has forced building companies to develop highly efficient and optimised building solutions. This project, with a loggia that works both as an extended living room and a glazed balcony offers a highly economic viable alternative to standard balconies. This alternative is likely to attract build master since the area of the loggia will be part of the apartment area, i.e. included in the area for rent..
Studenters upplevelse av information overload i informationshanteringsprocessen - Implikationer för högskolebiblioteket
Information overload occurs when the amount of information exceeds the individual s capacity to efficiently process and use the information available. In this situation information instead of being an asset becomes a load. This interview study deals with college students experiences of information overload when working on their thesis. Focus lies on use of Internet based information resources. The main result was that the students experienced information overload in specific situations and steps of the process.
E-marketing - ett modernt kommunikationsverktyg : En studie som presenterar alternativa marknadsföringsåtgärder
Background: The use of digital marketing channels during the last years has increased significantly, especially the use of marketing on the Internet. Hence the communication chart of marketing has been redrawn. The technological development has had a major impact on the marketing discipline. The integration of information technology and marketing has resulted in the emergence of a new field, namely e-marketing. Hence the need for further research is desirable.Purpose: The purpose of this study is to examine alternative marketing procedures that a company can apply to increase the digital awareness and manage their customer relationships.Theoretical framework: Theories regarding digital marketing cycle, SEO and customer relationship.Method: This research is based on data collected through a primary semi-structured interview with a company active in the corporate information industry which also provides a RFQ service.
XML som informationsbärare för EDI
Information handling has been a key issue for different companies for a long time. Electronic Data Interchange (EDI) is used to transfer different business documents from one company to another. This is done in such way that the information itself is separated from how this information is stored and handled in the companies internal systems. As different companies have different systems there is a need for a standardised format for this exchange. There is a big difference between EDI-systems based on what kind of EDI-standard is used.
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.
Morgondagens motorteknik under dina fötter
Want to help making the world a better place? Do it with HypOCycle!HypOCycle is a bachelor thesis that started in September 2007. The project is owned byLars-Johan Hjertz and Erik Westerlund.HypOCycle is probably the only bike in the world that has a linear pedal movement. Themovement comes from a new engine technique that hasn?t even been brought to themarket yet.
Alternativ Hollywoodestetik : En studie över fyra filmers förhållande till Classical Hollywood Cinema
This essay studies stylistic differences as well as homage?s between four films produced in two different contexts, New Hollywood and alternative aesthetics today in America. This is done in order to answer the question how alternative Hollywood works against or with Classical Hollywood Cinema in cases like style and narrative. The Work is done by a theory of neoformalism and the definition made by them of Classical Hollywood Cinema. The essay finds small changes, although kind of important witch are mainly shown in editing and causal motivation.