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900 Uppsatser om Fuel reduction - Sida 49 av 60
Unga invandrares uppfattning av fenomenet hälsa och ohälsa : En tolkning av livserfarenheter ur ett fenomenografiskt perspektiv
Västerländsk mindfulnessmeditation har sina rötter i tusenårig buddhistisk tradition, främst genom vipassana- och zentraditionerna. Senaste tiden har mindfulness ökat i popularitet och blivit en accepterad klinisk metod i former som mindfulness based stress reduction. Möjligheten att undersöka dess effekter genom neurovetenskapliga metoder bidrar med intressant och viktig forskning om mänskligt välbefinnande. Dock har tidigare studier visat på bristande samstämmighet vad gäller resultat och metod. Uppsatsen är en litteraturstudie där det huvudsakliga syftet är att utifrån nyare studier undersöka de tydligaste effekterna på hjärnfunktion och struktur av långvarigt praktiserande av mindfulness utifrån vipassana- och zenmeditation.
Undersökning av deponerat ferrokromstoft : Utvärdering av ny behandlingsmetod
The production of ferrochromium alloys at Vargön Alloys AB contributes to formation of unwanted ferrochromium dust, which contains toxic Cr(VI). The dust is since summer 2005 treated with an iron-sulphate solution to reduce Cr(VI) to the non-toxic Cr(III). A year later the treatment technique was improved and disposal occurs in cells on the landfill. The cells can be up to 300 m3 and the edges can be made out of fro example concrete. Tests are conducted on the treated dust when it is disposed.
LCA av dricksvattendesinfektion : en jämförelse av klor och UV-ljus
Disinfection methods for drinking-water produced at the two water works of Stockholm Water Co are compared in this study. Three different nethods are compared; disinfection with chlorine gas, disinfection with sodium hypochlorite and disinfection with UV-light and monochloramine. The method used is Life cycle assessment, LCA. LCA is defined as the compilation and evaluation of the inputs, outputs and potential environmental impact of a product system shroughout its life cycle. The environmental burden is compared for the three different disinfection methods.
Metoder för lastprioritering i fjärrvärmecentraler
A problem in the field of district heating is the oil burners needed to provide power when a peak load occurs. One possible way of reducing the needed amount of oil is to reduce the power demand for space heating in the district-heating substations when the need for district heating water exceeds a certain limit. This can be done by use of a locally working controller function.In this Thesis the options concerning load priority are evaluated. To evaluate the potential for using controller functions concerning peak load priority an experiment was brought out in a chosen district-heating substation. The impact on the indoor thermal comfort during a heat reduction was also taken into account.
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.
Säkring av samtliga kritiska skruvförband i mellanstora asynkronmotorer
The purpose with this thesis is to get a compilation of all the critical bolted joints of all enginesproduced at LV Motors. ABB LV Motors produces induction engines with seven shaft heights. Eachengine size exists several variants of components ex. standard shield and flange shield. Depending onwhich components the engine is equipped with arises various types of strains in the engine's parts,certain assembly ways are more favourable than other.The most critical parts in the engine from a mechanical point of view are the screw units betweenshield/stator, feet/stator and bearing cover/shield.
Kustnära ekosystem som skydd mot naturkatastrofer : en litteraturstudie från ett riskhanteringsperspektiv
Research suggests that society's vulnerability to natural disasters along coasts could increase as a result of climate change, which is likely to lead to elevated sea levels and possibly an increase in the occurance of meteorological phenomena such as storms and tropical cyclones. Following the Indian Ocean tsunami disaster in 2004 and Hurricane Katrina in 2005, both of which received considerable media attention, empirical data has indicated that coastal vegetation might be able to protect and reduce damages to coastal communities during tsunami events and tropical cyclones.The aim of the essay has been to study the function of coastal ecosystems as protection against tsunami waves and storms from a risk management perspective, meaning that I have, through an overview of scientific articles, compiled current research on how coastal ecosystems can attenuate storm surges and tsunami waves, and analysed how this knowledge can be put into practice in coastal communities from a risk management perspective, i.e. if coastal ecosystems are a viable risk reduction measure, are practically applicable, and if so, how they could be applied.There is empirical evidence suggesting that coastal ecosystems, particularly mangroves, can reduce the strength of a tsunami wave, but full scientific consensus on this issue has not yet been reached. With regard to protection against storm surges, there is extensive scientific evidence that coastal vegetation can mitigate damages and reduce the height of a storm surge, although the wave has to traverse several kilometres inland through thick vegetation for the protection to be effective. A synthesis in the form of a figure regarding the many physical factors that influence wave development through coastal ecosystems has been created in an attempt to simplify and explain the phenomenon.The conservation and restoration of coastal ecosystems can be justified from a risk management perspective, but planting new forest belts for the purpose of disaster mitigation is quite unrealistic and can rarely be sustainable, since, for protection to be effective, the forest belt must extend several kilometres inland from the coast, and would thus likely prove difficult to implement along coastal societies..
Investeringar i småskalig vattenkraft vid befintliga dammar : - En studie av teknik-, ekonomi- och miljöfrågor
In this thesis a method for evaluating investments in small scale hydro power is presented. An analysis of the future position that small scale hydro production will have on the Nordic electricity market is also carried out. This is done by an inventory of technology and economic and environmental aspects. The inventory is also a guide as to how the project should be implemented.Hydrolyzer is the name of the Excel tool developed to evaluate investments. The tool requests input data from the user and then evaluates the investment and generates a sensitivity analysis.
Teknik för vårskörd av hampa till stråbränsle :
Hemp is an annual energy crop that fits very well in Swedish crop rotations. It is an interesting crop with many benefits, for example its ability to establish a large quantity of biomass in one year. Hemp is easy to grow and out-competes unwanted weeds through its aggressive growth pattern without the need for pesticides. Interest in growing hemp and other energy crops is currently decreasing, apparently because of high grain prices. These high prices give a higher net profit that we believe could partly cover the cost of hemp cultivation, while the hemp in turn would improve the crop rotation and thus repay its debts in the form of increased yields of other crops.
The great disadvantage of hemp is the lack of knowledge about spring harvest of the crop.
Analys av revisionsarbetet på Forsmarks kärnkraftverk
This thesis is the final part of bachelors program of Nuclear Engineering at UppsalaUniversity (program code KKI1). The work has been carried out in cooperation withForsmark Kraftgrupp AB. The topic studied deals with possible improvements ofefficiency at the planning department at block 2 in Forsmark i.e. FMP2.FMP2 plans and coordinates over 3,000 operations which is carried out during theannual overhaul of block 2 in Forsmark. Inspections, fuel replacement and repairs areincluded in the annual overhaul.
Privata och offentliga riskreduceringsmekanismer och dess inverkan på beviljande av handelskrediter
Bakgrund och problem: Majoriteten av försäljningen mellan företag, samt mellan företag och offentlig sektor sker via handelskrediter. Detta leder till att företagen ofta blir utsatta för risker i form av sena och uteblivna betalningar. I sådana situationer finns det behov av riskreduceringsmekanismer som ska reducera och minimera dessa risker. Mekanismerna för reducering av risker har vi fördelat i två kategorier, privata och offentliga. Avsikten med uppsatsen är att undersöka vilka av dessa mekanismer som har störst inverkan på beviljandet av handelskrediter.
Effekten av längre tids praktiserande av mindfulnessmeditation på hjärnfunktion och struktur ? en summering utifrån nyare studier av vipassana- och zenmeditation
Västerländsk mindfulnessmeditation har sina rötter i tusenårig buddhistisk tradition, främst genom vipassana- och zentraditionerna. Senaste tiden har mindfulness ökat i popularitet och blivit en accepterad klinisk metod i former som mindfulness based stress reduction. Möjligheten att undersöka dess effekter genom neurovetenskapliga metoder bidrar med intressant och viktig forskning om mänskligt välbefinnande. Dock har tidigare studier visat på bristande samstämmighet vad gäller resultat och metod. Uppsatsen är en litteraturstudie där det huvudsakliga syftet är att utifrån nyare studier undersöka de tydligaste effekterna på hjärnfunktion och struktur av långvarigt praktiserande av mindfulness utifrån vipassana- och zenmeditation.
Utveckling av processparametrar inom en hårdmetallindustri
This report analyzes and examines a hypothesis for finding a method to optimize thelength of the delubrication process time based on a total charge weight. The work hasfocused on the holding time for delubrication and the total charge weight.An important step in the manufacturing chain of cutting tools is when the greenbodies undergo the sintering process. Today, the delubrication step has the sameprocess time independent of the total charge weight. An implementation of a methodto adjust the delubrication process time would give more consistent quality of thecutting tool´s internal characteristics but also reduce the time course of the sinteringprocess. In the present project two methods for this goal were tested, thedevelopment of an algorithm and a weight interval subdivision with associateddelubrication process times.During delubrication a pressure increase is observed due to the decomposition of thePEG in the powder mixture.
Termisk hantering av litium-jon- batterier i elektriska drivsystem
The automotive market is currently undergoing a historical change where stricter emission legislations and ever increasing fuel costs have intensified the search for effective alternatives to the conventional internal combustion engine, which has resulted in a substantial trend towards electrification of powertrains. Storage of electrical energy is the fundamental component in this technology where the lithium-ion batteries are currently considered as the most appropriate solution. Lithium-ion batteries, however, as other types of batteries, can only be used efficiently and durably within a specific temperature range.This Master thesis has been carried out in collaboration with Electroengine in Sweden AB, situated in Uppsala, which has an ongoing project regarding development of a modular battery system for electric powertrains. The project is at a stage where an initial prototype has been developed which provides the foundation for this thesis. The study has addressed the battery system performance from a thermal perspective, in order to validate the ability of the system to create a thermally serviceable environment for the lithium-ion battery cells.
Analys av massapumps- och mixerarbete vid Metsä Board Sverige AB, Husums Fabriker : Energibesparingsåtgärder vid blekeri 4 & 5 med jämförelse mot ny utrustning
Husums plant has a selection of different pulp pumps at bleaching plant 4 and 5. The displacement- (HC-pump, Sund Defibrator PTD-60) and centrifugalpumps (MC-pump, MCA 42-200, MCP 30/20) are of interest in this report. The centrifugal pumps are controlled by throttle valves, which result in an energy loss. Chemical mixers are used to mix ClO2 into the pulp before proceeding into a holding tower where the bleaching process occurs.The energy demand of the different positions has been measured or calculated to be used in comparisons against new equipment. Quotations were requested and delivered from Valmet and Sulzer.