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3426 Uppsatser om Energy efficiency measures - Sida 59 av 229
Ethanol for Scania's Future - A Scenario Based Analysis
Abstract Title: Ethanol for Scania?s future ? A scenario based analysis Authors: Anna Hansson and Julia Persson Tutors: Annette Cerne ? Department of Business Administration, Lund University Jonas Holmborn ? Head of Advanced Combustion, Engine Development, Scania Lennart Thörnqvist ? Department of Energy Sciences, Faculty of Engineering, Lund University Problem: Oil-based products are the dominating fuels in the transport sector but alternative fuels are currently challenging the world-wide dominance. The large number of alternative fuels that are under development at present makes the future fuel-market impossible to predict. Scania?s ethanol project is associated with a number of uncertainty factors that are beyond the company?s control.
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.
Miljöeffekter av alternativa system för behandling av hushållsavfall i Santiago, Chile : en jämförelse mellan deponering och förbränning med energiutvinning
This report was written by Lisa Bengtson and Hanna Paradis and describes the
degree thesis "Environmental impacts of solid waste treatment in the Metropolitan
Region, Santiago, Chile ? a comparison between current system and incineration
with energy recovery". The purpose of this thesis was to investigate if incineration
with energy recovery could be motivated through an environmental perspective as
an alternative to landfilling of solid waste in Santiago, Chile. The study was
performed with Life Cycle Analysis as a theoretical base.
In Santiago, situated in the thirteenth region of Chile, Región Metropolitana, lives
6,5 million inhabitants. The major part of the solid waste produced in the region is
landfilled on three different sanitary controlled landfills situated outside the city
center.
Energieffektiva bostäder i Kurdistan - Förslag på bostadshus i den kurdiska delen av Irak
Staden Sulaymaniyah ligger i den kurdiska delen av Irak och har på senare år utvecklats då många valt att flytta från landsbygden till den centrala delen av staden. Nybyggandet sker under tidspress och långsiktigt hållbara lösningar prioriteras inte. Målet är att ta fram ett hus som är anpassat för majoriteten av befolkningen och samtidigt få ett bra och energieffektivt inomhusklimat. En faktainsamling genomfördes för att ge bakgrundsinformation till projektet. Vidare gjordes en planlösning till huset i AutoCAD vilken har använts som grund till utformningen av huset och smarta lösningar.
Butikschefens Egenskaper och Produktivitet i Butik - lokalt ledarskap och ekonomiskt resultat i butik
This thesis reports on the methodology and results of a study with one retailers 73 units to investigate factors of the store managers leadership that influence productivity performance in store. The study determine the impact of ten independent variables in terms of the store managers leadership on four performance measures: (3) three productivity measures: Sales Over Labor (SALOL), Sales Over Inventory (SALOI) and Sales Over Square-metre (SALOS) and (1) one profit measure: Contribution Income Over Square-metre (CIOS). The result shows that the leadership factors give no more explanation to the economic results after factors of local market condition and the store attributes are taking in to account. The store manager's leadership can though influence his or her decision-making in-store. The store manager's decision to staff the store more intense (higher service-intensity) can increase the level of contribution income over square metre in-store..
Implementation av ett kunskapsbas system för rough set theory med kvantitativa mätningar
This thesis presents the implementation of a knowledge base system for rough sets [Paw92]within the logic programming framework. The combination of rough set theory with logic programming is a novel approach. The presented implementation serves as a prototype system for the ideas presented in [VDM03a, VDM03b]. The system is available at "http://www.ida.liu.se/rkbs". The presented language for describing knowledge in the rough knowledge base caters for implicit definition of rough sets by combining different regions (e.g.
Viktoptimering av ett kompositchassi till en multimodal lättviktsfarkost
This report describes the master thesis project ?Weight Optimization of a Composite Chassis for a Multimodal Lightweight Vehicle? which is a part of the Master program in Naval Architecture and a part of a research project at the Centre for Naval Architecture, KTH. Demands on smart and energy efficient transport solutions are continuously increasing. In the Stockholm region the citizens are expected to increase with 25% and the road vehicles with 80% until 2030, putting high demands on the traffic system. Using a small multimodal vehicle deals with this problem and uses both the land and waterways for transportation.
Användarvänlighet i blötutfodring : enkätstudie för smågrisproducenter
It is possible to affect the feed costs in different ways. By steeping or fermentation the digestibility of the feed is improved for the animals with a natural process in the wet feeding system Steeping means that the feed is soaked some hours before feeding. This process activatesenzymes and improves the digestibility of for example phosphorus in the feed and make it more accessible to the animal. Wet feeding can be fermented or not. Fermentationmeans that the feed has been soaked for a certain length of time so that a biological process is started.
Bolagsstyrning och tillgänglighet : Hur funkar det?
AbstractThe OMX Nordic Exchange Stockholm requires all large companies to apply the Swedish Code ofCorporate Governance. A revised code will be applied from July 2008. The purpose of this paper is toidentify the accessibility of information on corporate governance and in particular how the compliance,concerning the Swedish Code of Corporate Governance in the perspective of an internet active generalpublic.This paper is a complete census of the companies at the OMX Nordic Exchange Stockholm whocomplies with the code. Each company website has been visited and a comparison between the sectorsat the OMX Exchange Stockholm has been performed.Results: 96% of the companies present the members of the nomination committee. 94% presents thenomination committees proposal of the company board members, though only 33% of the companies inthe Energy sector.
Computer Modelling of the Influence of Surface Topography on Water Repellency and a Study on Hydrophobic Paper Surfaces with Partly Controlled Roughness
A computer model based on minimization of the free energy, capable to predict contact angles and spreading transitions between Wenzel and Cassie mode for drops placed on surfaces with different topography were implemented in matlab. Simulations were compared with experiments documented in the literature. These showed that reported transitions between Cassie and Wenzel mode can be explained by minimization of the free energy. In this report, a study on the possibility of constructing water repellent paper surfaces with a combination of treatment with octadecyltrichlorosilane and topography changes, is included..
OTEC-Ett energialternativ för enhållbar ö
Ocean Thermal Energy Conversion (OTEC) is a technology that utilizes the temperaturedifference in oceans between the warm surface water and the cold water at 1000 m depthto produce electricity. The purpose of this report is to investigate if OTEC with its synergiescould become a commercially feasible energy solution for a small island. A literature reviewis conducted to explore the different OTEC technologies and to what extent the threesynergies; fresh water, air conditioning and aquaculture, could be used. In order to calculatethe profitability of these synergies there is also a study conducted on the conventionalmethods and cost of fresh water production, aquaculture and air conditioning. A model is setup using a scenario of a small tropical Island with population of 100 000 people.
Hur effektiva är de egentligen?: En evaluering av tre webbaserade söktjänster
The purpose of this masters thesis is to evaluate the retrieval effectiveness of three different search engines on the Internet: Google, Yahoo! and MSN Search. We have constructed 25 topics and queries with varying contents, in order to test the width of the search engines as much as possible. In every search we have evaluated the first 20 hits in each of the search engines. The measures we have used are precision and cumulated gain. Precision is based on a binary scale and cumulated gain is calculated by means of a non-binary relevance scale.
Passivhus ur en brukares perspektiv
Ett passivhus är ett hus som i stort sett enbart värms upp av människorna och elapparaterna som finns i huset. Särskilda krav för att få kalla huset för passivhus måste uppfyllas.Vi har gjort en enkätundersökning på tre olika passivhusprojekt för att utreda vad de boende tycker om inomhusklimatet. De utvalda projekten finns i Värnamo, Frillesås och Glumslöv. Enkätsvaren visar att de boende i Frillesås är mycket nöjda, medan mer än 50 % av dem som bor i Glumslöv tycker att det är för varmt på sommaren och för kallt på vintern. För att utreda om de olika konstruktionerna har någon inverkan på inomhusklimatet har beräkningar och simuleringar i datorprogrammen VIP+ och IDA gjorts.
Motor till unikt luftvärmeväxlarsystem
Gtherm is an innovation company who has an unique air heat exchanger underdevelopment. The purpose of this thesis is to provide data of suitable motors for theheat exchanger and to find suitable motor suppliers.A motor specification was designed. It is an important basis for the search of suitablemotors. A compilation was made of nine motor suppliers and the suitable motorsfrom those. The compilation can be used by GTherm in their choice of suppliers andmotors.The compilation of the demands on the motor and analysis of suppliers indicated thatthere were no standard motors available to GTherms air heat exchanger.
Energieffektivisering av klimatskal med hänsyn till kulturhistorisk värdering : Fallstudier av tre befintliga småhus från 1900-talet ur bevarandesynpunkt
Allt hårdare lagkrav gör att det är svårt att energieffektivisera befintliga byggnader utan att förändra deras utseende.Syftet med examensarbetet är att utreda hur stor energieffektivisering, för tre befintliga småhus uppförda under 1900-talet, som är möjlig att uppnå genom förbättring av byggnadernas klimatskal, det vill säga tak, väggar, golv, fönster och dörrar, utan att förvanska byggnadernas utseende och samtidigt bevara deras kulturhistoriska värden.Arbetet bestod av en förstudie där tre byggnader identifierades, ett undersökningsskede där information om byggnaderna togs fram och ett slutsatsskede där energibesparande åtgärdsförslag togs fram och utvärderades. Byggnader som var goda representanter för sin tid och stil söktes. Byggnader från 1910-talet, 1930-talet och 1970-talet, lokaliserades. Sedan gjordes det fallstudier med intervjuer och inventeringar. För att utreda byggnadens klimatskal utfördes u-värdesberäkningar och energiberäkningar av befintliga byggander och byggnader baserade på föreslagna åtgärdsförslag.Ingen av byggnaderna nådde efter föreslagna åtgärder ner till passivhuskravet 59 kWh/år/m2 Atemp eller BBR-kravet 110 kWh/år/m2 Atemp för en byggnads specifika energianvändning.