In ordinary image coding, the same image quality is obtained in all parts of an image. If it is known that there is only one viewer, and where in the image that viewer is focusing, the quality can be degraded in other parts of the image without incurring any perceptible coding artefacts. This master's thesispresents a coding scheme where an image is segmented into homogeneous regions which are then separately coded, and where knowledge about the user's focus point is used to obtain further data reduction. It is concluded that the coding performance does not quite reach the levels attained when applying focus-based quality degradation to coding schemes not based on segmentation.

Denna rapport behandlar framtagandet av en modell för beräkning av lastbilars nyttjandegrad. Vidare beskrivs hur denna modell har implementerats och vilka möjliga ekonomiska besparingar som finns att hämta med ett ökat nyttjande. Den kostnadskalkyl som upprättades för att kunna beräkna dessa möjliga besparingar resulterade i en kalkylerad timkostnad på 551 SEK per timme och lastbil. De resultat som beräkningarna av lastbilarnas nyttjandegrader gav, tyder på att bilarna i den södra regionen, som förväntat, hade en klart lägre nyttjandegrad än övriga. Mer oväntat var dock att detta till stor del berodde på ett lågt kapacitetsutnyttjande. Ett förslag på ny utformning av den databas vari information om utförda transporter registreras har också tagits fram. Om databasen omarbetas enligt detta förslag, eller på annat lämpligt sätt, skulle den här typen av beräkningar kunna snabbas upp betydligt. De totala ekonomiska besparingarna som skulle uppnås om samtliga bilar höll ett kapacitetsutnyttjande och ett tidsutnyttjande motsvarande medelvärdet av de bästa 25 procenten i respektive kategori, motsvarar 14,1%, alltså nästan 36 miljoner SEK per år. Stora problem ses dock med att kunna förverkliga dessa besparingar, åtminstone på någorlunda kort sikt.

An automatic road toll system enables the passing vehicles to change lanes and no stop is needed for payment. Because of different weight of personal cars, busses, lorries (trucks) and other vehicles, they affect the road in different ways. It is of interest to categorize the vehicles into different classes depending of their weight so that the right fee can be set. An automatic road toll system developed by Combitech Traffic Systems AB (now Kapsch TrafficCom AB), Joenkoping, Sweden, classifies the vehicles with help of a so called height image. This is a three dimensional image produced by two photographs of a vehicle. The photographs displays the same view but are mounted with a little spacing. This spacing makes it possible to create a height image. The existing classification uses only length, width and height to divide vehicles into classes. Vehicles of the same dimensions would then belong to the same class independent of their weight. An important example is busses and lorries (trucks) which often have the same dimensions, but trucks often have greater weight and should therefore require a larger fee. This work describes methods for separating busses from lorries with the help of height images. The methods search for variations in the width and height, and other features specific for busses and lorries respectively.

The residual gas fraction is an important parameter to get good performance with high efficiency and low emissions in the HCCI-engine. The goal in this thesis is to formulate an algorithm for estimation of the residual gas fraction based on the cylinder pressure. The estimation is improved if also the exhaust gas temperature is used together with the cylinder pressure. The formulated algorithm has then been tested on data from a single cylinder engine running in HCCI-mode during steady state conditions. An error of 4% was noted compared with the residual gas fraction obtained from simulations. The thesis also investigates the effects of some possible error sources.

In the report a model using a reduced reaction analysis has been used to see if it is possible to predict knock. The model is based on n-heptane combustion, but it is used for iso-octane. The model was supposed to be able to adapt to different fuels, but it is shown to be unable to do so. Further, the model has been compared to an existing method for predicting knock, known as knock index, to see if any improvements could be made. When comparing the model to the knock index, it has shown that no big advantages can be found using the new model. It is more time consuming and is not able to work with simulated input, instead of measured. It can however predict if knock occurs with a good reliability, but compared to the knock index it is not an improvement.

The goal of this project is to implement a system to analyse an audio signal containing speech, and produce a classifcation of lip shape categories (visemes) in order to synchronize the lips of a computer generated face with the speech. The thesis describes the work to derive a method that maps speech to lip move- ments, on an animated face model, in real time. The method is implemented in C++ on the PC/Windows platform. The program reads speech from pre-recorded audio files and continuously performs spectral analysis of the speech. Neural networks are used to classify the speech into a sequence of phonemes, and the corresponding visemes are shown on the screen. Some time delay between input speech and the visualization could not be avoided, but the overall visual impression is that sound and animation are synchronized.

This thesis develops an algorithm for tracking the boundary of an airbag throughout an image sequence. The algorithm is designed to work even if various problematic features, e.g. objects in the background, are present in the image. The work is built on an existing commercially available image processing and analysis suite targeted at the automotive industry. The software suite runs on standard PC hardware. Firstly, improvements to the airbag tracking algorithm already available in the suite are considered. Testing reveals that these measures are not sufficient to overcome the problems posed by the problematic image sequences. A new tracking algorithmis then proposed. It consists of a Canny edge detector, optional steps to enhance feature detection by removing edges in the background and edges interior to the boundary of the airbag and finally an active contour. The role of the active contour is to produce a closed curve while imposing smoothness constraints on the detected boundary. The active contour is in each frame initialized by linearly extrapolating the contour from previous frames. The algorithm works very well and it is fast enough to run on slower machines than was initially targeted.

Technical systems of today are often complex and integrated. If a fault occurs, the consequences can be disastrous both for the system itself and its surroundings. To maintain the operation and the security it is necessary to have a surveillance system which can detect a fault in an early stage. In this thesis two structural methods for fault isolation analysis are discussed. The result from the studied algorithms shows what fault isolation properties a diagnostic model is expected to have. If the isolability is not good enough, it also gives information on where further modelling needs to be done. To base a comparison of the two structural analysis algorithms on, four criteria are defined concerning for example realizability of residuals and time complexity. One interesting part of the methods is how dynamic models are handled. It is shown how differential constraints can end up in differential cycles which implies calculatory problems and what effects structural differentiation has on a system. The algorithms have been tested on an application from the research training network DAMADICS. The result shows how different types of input models in this case give the same result.

Den kraftiga ökningen av bredbandsuppkopplade hem världen över har lett till ett stort användande av s.k. webradio. Miljontals användare lyssnar dagligen på de tiotusentals tillgängliga webradiostationerna. Webradio är ett sätt att via Internet och TCP/IP sända radio. Oftast används de populära MP3-formatet men nya bättre standarder håller på att etableras. Tyvärr är man idag hänvisad till att lyssna på webradio via sin hemdator. Det är både krångligt och tar lång tid innan man kan börja lyssna, en rad program måste installeras och man måste leta på Internet för att hitta en station man vill lyssna på. Utbudet är dock enormt varför detta inte är en temporär fluga utan någonting som kommit för att stanna! Det här examensarbetet har gått ut på att i en liten, billig elektronisk krets implementera en MP3-baserad webradio. Rapporten ger en överblick över de olika komponenterna som krävs samt hur jag praktiskt löst de olika problem jag ställts inför. Tyvärr blev det inte implementerat i en enda krets utan i två, detta på grund av att tekniken som används är så pass ny att ingen stabil utvecklingsmiljö fanns att tillgå vid projektets start. / The large increase of broadband connections in the world has lead to a rapid spread in the use of web radio. Millions of users listens every day to the many thousands available stations on the Internet. Web radio is a way to broadcast radio over the Internet. The most popular format to code the media is by use of MP3, but newer and better methods are on there way. Today you have to use a personal computer to listen to Web radio. This is both time consuming and a potential source of technical frustration. You have to install several programs and then search the Internet to find a station to listen to. Despite the hassle Web radio offers such a variety of music genres to give it a solid future. The objective of this thesis is to give an overview of the work I have done and the problems I have run into, implementing an MP3-based Web radio receiver in a small inexpensive electric circuit, completely independent of a personal computer. This report gives an overview of the different problems I have been faced to during my work. Due to the lack of stable development environment at the time of the programming, I was unable to implement my solution on one circuit and had to use two circuits.

Detta examensarbete har utförts på och i samarbete med ITN, Institutionen för Teknik och Naturvetenskap, vid Linköpings Universitet. Problemställningen härrör från tidigare projektsamarbete mellan Linköpings Universitet, Telia AB och Ericsson. Uppgiften består i att ta fram en optimeringsalgoritm som använder sig av ett nytt angreppssätt genom att försöka minska osäkerheten på indata.