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268 Uppsatser om Compression algorithm - Sida 17 av 18
Optisk undersökning av dieselsprayer från en höghastighetsroterande insprutare
There have been changes in Earth?s climate system on both global and regional scale since the pre-industrial era and some of these changes are due to human activities such as the combustion of fossil fuels. This calls for the development of engines with a higher efficiency and less harmful emissions. One interesting concept is the Homogeneous Charge Compression Ignition (HCCI) engine, which has the advantages of potentially low emissions combined with high efficiency. However, HCCI with diesel fuel requires a relatively long fuel/air mixing time to ensure a "homogenous" charge.
Vidareutveckling av häftfixtur för sammansvetsning av Volvo hjullastares lyftramverk : Ett projekt med syfte att effektivisera produktionen
This report is about how HDR (HighDynamicRange) can be created and used in combination with Tone mapping. This work has been carried out together with Kapsch TrafficCom AB in Jönköping.The objective of this project is to:Evaluate and investigate the effects given to pictures by HDR and tone mapping.Evaluate if the technology may lead to improvements in Kapsch?s systems.To construct a program which is able to handle some form of tone mapping or HDR-algorithm.These questions will be answered in this report:What kind of effects has HDR and tone mapping-algorithms on pictures?Can the HDR-technology give better data in Kapsch?s systems?The research method used in this report is called action research. This means the authors has investigated the technology by reading different documentations and by testing different algorithms to see what kind of result they give. The report describes some of the tests made to see if the technology is appropriate in Kapsch?s system.There is two smaller reports made by the authors which documenting some of the work.The first report describes the work with different settings for a camera to create pictures with HDR-quality.
En jämförelse av krypteringsalgoritmer
Today the Internet is used more and more as a transportation for information.
Much of the information is confidential and should not be read by those not
privileged. To protect the information from unauthorized access cryptography
can be applied. The cryptography algorithms in use today all have their pros
and cons. They are therefore suited for different applications.
Kinematisk och dynamisk modellering av den haptiska enheten TAU i sex frihetsgrader
The thesis presents an optimally designed kinematic structure for a new 6-DOF haptic devicebased on TAU configuration. The configuration of the TAU-2 proposed by Suleman Khan andKjell Andersson [1] was modified and its mobility was verified by using Grübler criterion tohave a 6 DOF. Analytical kinematic models for the inverse and forward kinematics weredeveloped for the haptic TAU configuration to determine a set of optimal design parameters.Kinematic performance indices such as volume of the workspace, kinematic isotropy and payload index, were defined based on the singular values of the Jacobian matrix. The Jacobianmatrix was scaled to homogenize the physical units. The Jacobian matrix dependent on theposition and orientation of the end-effector gives local isotropy and pay load index, so globaldesign indices were defined, which represent the performance of the mechanism in the wholeworkspace.
En jämförelse av krypteringsalgoritmer
Today the Internet is used more and more as a transportation for information. Much of the information is confidential and should not be read by those not privileged. To protect the information from unauthorized access cryptography can be applied. The cryptography algorithms in use today all have their pros and cons. They are therefore suited for different applications.
Aerodynamisk optimering av vindkraftverks rotorblad med en genetisk algoritm, BEM-teori, och XFOIL
This study presents a methodology that enables the annual average power of a wind turbine to be increased by automatically optimizing it?s airfoil, twist and chord dis- tribution. As a part of the study the software SiteOpt has been developed. This software connects the open source software XFOIL with the blade element momen- tum theory. XFOIL gives lift and drag coefficients which enable the blade element momentum theory to predict the power of a wind turbine at different wind and ro- tational speeds.
Feldiagnos för RM12 baserad på identifierade modeller
The jetengines of today are growing in complexity. Reliability for aircraft engines are of extreme importance, mainly due to safety reasons but also economical ones. This master thesis deals with faultdiagnosis in the turbine section of RM12, the engine used in Saab/BAe's Gripen. Three different faults which can occur in the turbine section was studied. These faults are: clogged fuel nozzle, hole in outlet guide vane and sensor fault.
Modellering och simulering av det evaporativa bränslesystemet i en personbil
This thesis work has been performed at the department of diagnosis and dependability at Volvo Car Company, Torslanda. The background of this project is based on interest in ascertaining how different factors possibly can affect a diagnosis method, which has been developed to find leaks in the fuel tank and evaporation system. According to the OBD II requirements leaks with an orifice diameter larger or equal to 0,5 mm, must be detected. The idea of the diagnosis method is to create an over pressure in the system with an air-pump. The current through the pump is measured and correlates to the power consumed by the pump.
Vindkraftsetablering i skog
This thesis assignment at C-level is focused on calculation models and prediction methodswhish can be used in the stage we call ?prospecting? of possible windmill locations. Thelocation is southeast of Halmstad at the Farm ?Stjernarpsgods?. The rapport has two mainareas directed towards this task.
Evaluation of Xilinx System Generator
This Master?s Thesis is an evaluation of the software Xilinx System Generator (XSG) and blockset for Matlab. XSG is a module to simulink developed by Xilinx in order to generate VHDL code directly from functions implemented in Matlab. The evaluation was made at Saab Avionics AB in Järfälla, north of Stockholm. In order to investigate the performance of this new module XSG to simulink, a model of a frequency estimator often used in digital radar receivers were implemented in Matlab using XSG.
Inverkan av flisig krossballast på betong
Concrete is one of the world?s most common construction materials and is composed of 70-80 % stone material. Today crushed stone is used as aggregate in concrete in order to replace natural aggregates due to strong environmental reasons. Stone crushing yields flaky material and in this thesis studies are made on the flaky particle shape and how it influence properties of concrete such as workability, rheology and strength. The concrete recipes used in this thesis have fixed values, the only variable is the flakiness of the crushed stone.
Utbytets och malningens inverkan på NSSC-massans egenskaper
Neutralsulfitkokning av björk möjliggör ett högt utbyte av hemicellulosa, vilket bidrar positivt till flutingens egenskaper och minskar vedkostnaden. Neutralsulfitkoket ska avbrytas när delignifieringen nått tillräckligt långt för att veden ska kunna defibreras skonsamt med en rimlig energiinsats, men innan nedbrytningen av hemicellulosa hunnit accelerera. Syftet med detta examensarbete var att undersöka utbytets och malningens inverkan på NSSC-massans egenskaper.En laboratoriestudie genomfördes där massan kokades till olika utbyten och maldes vid olika insatser. Resultatet av den studien användes sedan för att ställa om kokaren och raffinörerna på lämpligt sätt vid fabriksförsöken. Massaprover togs ut efter det andra kvarnsteget och skickades för analys.
Inverkan av försvagningar på bärförmåga för stålbalkar med långa spännvidder : En jämförelse mellan Eurokod och BKR
The purpose of this thesis is to investigate the degree of influence of holes in the web of steel beams with long spanson weakening of their bearing capacity. Making holes in the web of the beam generally reduces the bearing capacity of the beam. However, it might be necessary seen from both an architectural perspective as well as from a building services perspective by creating an opportunity for building installations.The objective of this thesis is to examine how much an I-beam can be weakened without sacrificing safety and functionality. The investigation has been done by using Finite Element Method through commercial software.The regulation for structural design of building structures in Sweden used to be specified in the document known as BKR. But this was replaced by the European norm Eurocode back in May 2011.
Car Lock Improved by Configurable Key
When a car owner want to lock or unlock his or her car today, it?s preferable done by using aremote control. The system is really comfortable when the car owner is using the remote.A problem arises if a thief gets the remote.The thief doesn?t have to know where the car is parked, an approximate estimation where thecar is parked is enough.For instance, it?s enough to know which car park the car is parked in. If the thief knows that,he/she can repeatedly activate the remote control while looking for a car indicating with lightsand sounds.Because of the fact that a car usually indicates that it has been unlocked by making a shortsound indication, there will be no problem finding the car.The purpose with this project is to make a prototype which makes it harder for a thief to findthe car.
Automatisk bullerdosreglering i hörselskydd
På bullriga arbetsplatser använder personal ofta hörselskydd med inbyggda högtalare för att lyssna på exempelvis musik i underhållningssyfte. Om användaren lyssnar på höga ljudnivåer under långa perioder kan bullerskador uppstå i dennes öron. Enligt lagstiftning måste nivån därför begränsas i förebyggande syfte.Bullernivån är ett genomsnitt av de ljudnivåer användaren exponerats för under en arbetsdag. Användaren måste vila öronen om gränsvärdet för bullernivån nås.Om man utnyttjar att det är ett genomsnitt kan användaren tillåtas lyssna på en hög ljudnivå under en begränsad tid för att sedan sänka den. Det går att bevara både säkerheten och lyssningsupplevelsen om en sänkning införs långsamt.Detta arbete beskriver hur en algoritm till en digital signalprocessor kan konstrueras för att reglera ljudnivån.Målsättningen var att algoritmen skulle skydda användarens hörsel utan att försämra lyssningsupplevelsen, och utan att förbruka mer energi än nödvändigt.I algoritmen ingick en prediktor som predikterar mängden buller användaren riskerar att utsättas för, om denne fortsätter lyssna på samma nivå.Långsamma sänkningar av ljudnivån kan då utföras i tid innan gränsvärdet nås.Det visade sig att algoritmen endast behövde ett fåtal samplingar per sekund för att skatta och reglera ljudnivån tillräckligt precist, vilket reducerade energiförbrukningen.Resultatet visar möjligheten att kombinera målen för säkerhet, lyssningsupplevelse och energieffektivitet i hörselskydd.Algoritmen implementerades inte på ett skarpt system.Den hade enbart tillgång till ljudsignalen användaren ämnade lyssna på i underhållningssyfte..