<p>To be able to evaluate different radio waveforms in a laboratory environment FOI in Linköping has developed an experimental system for radio communication called Rasmus. The system consists of a transmitter, a channel emulator and a receiver. The transmitter modulates a digital signal to a desired analogue waveform. The channel emulator is used to simulate a real radio channel. The channel emulator distorts the signal by splitting it up in several propagation paths. Each path has its own statistical distribution, delay and so on. The receiver digitises the signal and saves it in a memory. Analysis of the signal is performed in non-real time. The system has some limitations concerning signal bandwidths and channel models. </p><p>This Master Thesis deals with the problem of scaling the radio channel (with respect to noise, Doppler shift and fading) in order to examine signals that have properties outside the normal operation of the Rasmus system. </p><p>The radio channel studied is a Rayleigh fading channel with two independent propagation paths. A differentially modulated QPSK signal is used as input to the channel. The signal is filtered through root-raised-cosine filter in the transmitter and receiver to reduce the effect of inter-symbol interference. </p><p>Theoretical calculations result in a method, that describe which parameters that should be scaled and how they should be scaled. Simulations are carried out in order to verify the method.</p>

<p>Volume rendering applications are used in medical imaging in order to facilitate the analysis of three-dimensional image data. This study focuses on how to improve the usability of graphical user interfaces of these systems, by gathering user requirements. This is achieved by evaluations of existing systems, together with interviews and observations at clinics in Sweden that use volume rendering to some extent. The usability of the applications of today is not sufficient, according to the users participating in this study. This is due to a wide range of reasons. One reason is that the graphical user interface is not intuitive. Another reason is that the users do not rely on the technique to produce sufficient results that can be used in the diagnostic process. The issue of user confidence is mainly due to the problem of the generation and user control of the transfer functions used in volume rendering. </p><p>Based on the results of the evaluation a graphical user interface, including the most important and frequently used functions, is designed. A suggestion for how the transfer function can be generated is presented.</p>

<p>Slumptalsgeneratorer är bland de viktigaste byggblocken inom dagens säkerhetssystem och infrastruktur. Det finns dock en uppsjö av varierande implementeringsmodeller i såväl mjukvara som hårdvara. Att konstruera en slumptalsgenerator som har tillträckligt bra egenskaper för att användas i säkerhetssystem är inte någon trivial uppgift. </p><p>I denna rapport diskuteras de två huvud metoderna att generera slumptal, dels i mjukvara (PRNG), dels i hårdvara (TRNG). Olika synvinklar och angreppssätt att generera och testa slumptal diskuteras och utvärderas. Dessutom diskuteras för- och nackdelarna med de olika generatorerna och hur dessa kan vara sårbara om inte försiktighetsåtgärder vidtas. </p><p>Resultatet antyder på att valet av en slumptalsgenerator är högst beroende på den applikation dessa slumptal ska användas i. Det rekommenderas dock att man använder en TRNG (hårdvaru-generatorer) för att seeda en PRNG (Pseudo-Random Number Generator) eller att använda sig av en TRNG och då kompensera för den skeva sannolikhetsfördelningen som uppstår.</p>

<p>With the advance of the modern information society, the importance of reliable identity authentication has increased dramatically. Using biometrics as a means for verifying the identity of a person increases both the security and the convenience of the systems. By using yourself to verify your identity such risks as lost keys and misplaced passwords are removed and by virtue of this, convenience is also increased. The most mature and well-developed biometric technique is fingerprint recognition. Fingerprints are unique for each individual and they do not change over time, which is very desirable in this application. There are multitudes of approaches to fingerprint recognition, most of which work by identifying so called minutiae and match fingerprints based on these. </p><p>In this diploma work, two alternative methods for locating distinct features in fingerprint images have been evaluated. The Template Correlation Method is based on the correlation between the image and templates created to approximate the homogenous ridge/valley areas in the fingerprint. The high-dimension of the feature vectors from correlation is reduced through principal component analysis. By visualising the dimension reduced data by ordinary plotting and observing the result classification is performed by locating anomalies in feature space, where distinct features are located away from the non-distinct. </p><p>The Circular Sampling Method works by sampling in concentric circles around selected points in the image and evaluating the frequency content of the resulting functions. Each images used here contains 30400 pixels which leads to sampling in many points that are of no interest. By selecting the sampling points this number can be reduced. Two approaches to sampling points selection has been evaluated. The first restricts sampling to occur only along valley bottoms of the image, whereas the second uses orientation histograms to select regions where there is no single dominant direction as sampling positions. For each sampling position an intensity function is achieved by circular sampling and a frequency spectrum of this function is achieved through the Fast Fourier Transform. Applying criteria to the relationships of the frequency components classifies each sampling location as either distinct or non-distinct. </p><p>Using a cyclic approach to evaluate the methods and their potential makes selection at various stages possible. Only the Circular Sampling Method survived the first cycle, and therefore all tests from that point on are performed on thismethod alone. Two main errors arise from the tests, where the most prominent being the number of spurious points located by the method. The second, which is equally serious but not as common, is when the method misclassifies visually distinct features as non-distinct. Regardless of the problems, these tests indicate that the method holds potential but that it needs to be subject to further testing and optimisation. These tests should focus on the three main properties of the method: noise sensitivity, radial dependency and translation sensitivity.</p>

<p>This study has been carried out as a part of the EC funded project, SMARTDOC IST-2000-28137, with the objective of developing application components that provide highly interactive visualization and collaboration functionalities. The low-level components from the graphics library AVS OpenViz 2.0 are used as the development basis. The application components can be inserted into electronic documents that allow embedded controls such as web documents or Microsoft Word or PowerPoint documents. Instead of displaying results as static images, a SMARTDOC component provides the ability to visualize data and interact with it inside the document. </p><p>Although the principal goal of the SMARTDOC project is to create components in a number of different application domains this study concentrates on developing a medical imaging application component in collaboration with the project partners AETmed and professor Alan Jackson at the University of Manchester. By incorporating the application component into patient reports, the clinicians are provided the ability to interact with the 3D data that is described in the reports. To improve the usability of the component, it makes use of a visual user interface (VUI), which gives the user the ability to interact and change parameters directly in the visualization process. </p><p>Collaborative work over geographical distances is an area that is becoming increasingly common and thus more interesting. As the availability of bandwidth has increased and the communication technologies have advanced, many companies express their interest for this new practical method of work. A company with offices in different countries would benefit from collaborative techniques providing closer cooperation within the company. Specialized institutions and laboratories could gather much experience and information through collaborative research. Medical imaging and visualization technique are areas where distinct disciplines such as networking, user interfaces and 3D visualization naturally can be fused together in order to develop collaborative environments. The visualization components developed within the SMARTDOC project will be the foundation for collaborative application components integrated with the Microsoft DirectX^® multimedia library. In the medical imaging area, collaborative work can be used to improve diagnoses, journaling and teaching. </p><p>This study focuses on developing a prototype of an interactive visualization component for 3D medical imaging and creating a collaborative environment using a multimedia library originally meant for network gaming.</p>

<p>The company where this thesis was formulated constructs VR applications for the medical environment. The hardware used is ordinary dektops with consumer level graphics cards and haptic devices. In medicin some operations require microscopes or cameras. In order to simulate these in a virtual reality environment for educational purposes, the effect of depth of field or focus have to be considered. </p><p>A working algorithm that generates this optical occurence in realtime, stereo rendered computer graphics is presented in this thesis. The algorithm is implemented in OpenGL and C++ to later be combined with a VR application simulating eye-surgery which is built with OpenGL Optimizer. </p><p>Several different approaches are described in this report. The call for realtime stereo rendering (~60 fps) means taking advantage of the graphics hardware to a great extent. In OpenGL this means using the extensions to a specific graphic chip for better performance, in this case the algorithm is implemented for a GeForce3 card. </p><p>To increase the speed of the algorithm much of the workload is moved from the CPU to the GPU (Graphics Processing Unit). By re-defining parts of the ordinary OpenGL pipeline via vertex programs, a distance-from-focus map can be stored in the alpha channel of the final image with little time loss. </p><p>This can effectively be used to blend a previously blurred version of the scene with a normal render. Different techniques to quickly blur a renderedimage is discussed, to keep the speed up solutions that require moving data from the graphics card is not an option.</p>

<p>Denna rapport är en beskrivning av ett examensarbete utfört vid SPM Instrument AB i Strängnäs. SPM Instrument utvecklar och tillverkar produkter för konditionsmätning av maskiner. </p><p>Målet var att skapa en cd-presentation i redigeringsprogrammet Macromedia Flash 5.0, som på ett enkelt sätt med rörliga bilder förklarar en konditionsmätningsmetod som kallas för Stöt Puls Metoden.</p><p>Uppgiften löstes genom att först inhämta information om Stöt Puls Metoden, sedan utformades Flash-filmen och slutligen testades och utvecklades filmen tills dess att jag och SPM Instrument var nöjda. </p> / <p>This report describes a final-year project performed at SPM Instrument AB in Strängnäs. The company develop and manufacture products for condition monitoring of machinery equipment. </p><p>The goal was to create a cd-presentation in the computer software Macromedia Flash 5.0, with moving pictures which explains a condition monitoring method that is called the Shoke Pulse Method. </p><p>The task was solved by first finding out information about the Shoke Pulse Method, then the Flash-movie was created and finally the movie was tested and developed until both I and SPM Instrument was satisfied.</p>

<p>The idea for the thesis “Construction and implementation of a mobile prototype; The Lovebomb” originates from doctoral candidates Rebecca Hansson and Tobias Skog from PLAY Research Group at the Interactive Institute in Gothenburg. The object of the master thesis is to construct two working LoveBomb prototypes, one mother console belonging to the LoveBomb and blueprints for both. The LoveBomb (the picture to the right shows a possible design) is intended to encourage people to express themselves emotionally when situated amongst strangers in public spaces. Two buttons control the device, which contains a radio transceiver. By pushing the buttons the user can either send a happy message or a sad message. The LoveBombs in the vicinity receive the sent message and lets its user know which message that has been received by vibrating either a sad irregular pulse or a happy continuous pulse. While vibrating the LoveBomb send out a confirm message. The confirm message can only be received by a LoveBomb which has recently sent out a message. After receiving a confirm message the LoveBomb conveys this to the user by turning on a red LED (light emitting diode) and letting the LED shine for about half a minute. During this time the LoveBomb can only receive messages. If it receives a message, during these 30 seconds, the LED is turned off and the prototype starts vibrating according to the received message. Should a LoveBomb which has sent a message fail to receive a confirm message it conveys this to the user by turning on and off the LED three times. After this the prototype is ready to send another message. The picture below shows a state diagram of the LoveBomb. The mother console registers all the communication between the LoveBomb, by pushing a button the user can see how many happy respectively sad messages that has been sent. Our workstarted with the doctoral candidates communicating their thoughts and wishes concerning the prototype to us. We organized this information into a requirement specification. We started the development of the Lovebomb and the belonging mother console by selecting a suitable micro controller. We choose PIC16C84 from Microchip but changed later to its successor PIC16F84, because the latter was easier to get a hold of. The micro controller controls all the other components. When we knew how to program the micro controller, we started working with a transceiver, suggested by the doctoral candidates, DR3001 from RFM. After establishing a meaningful communication between two micro controllers connected with on transceiver each, this was the hardest and most important part, we began working with not so vital component such as diodes, vibrators and buttons. When we were finished with the implementation and construction we examined the prototype and compared it to the requirement specification. To our satisfaction the prototype did not differ a lot from the requirements and the existing differences were improvements from the original idea. During the development process both of us learned a lot about assembler programming, electrical engineering and radio communication.</p>

<p>TV and radio services have always been distributed over analogue broadcasting networks and been received on a TV -set or a radio receiver. Today this situation is changing due to digitalization and convergence between broadcasting, telecommunications and data communications. Other terminals, such as a PC, can also receive TV and radio services. Digital TV and radio can offer additional services such as e-commerce, electronic program guides and content synchronized to the TV and radio shows. If these services are to be received by several receiving terminals with different properties, the services must be adapted to the terminals. This can be done by scaling the services, meaning that the appearances and functionality of the services vary depending on the terminals’ properties. In this thesis scalable services are examined from a terminal point of view. Present and future receivers, platforms and possible methods to achieve scalability are presented, and their effects on scalable services are discussed.</p> / <p>TV- och radiosändningar har fram till nyligen endast distribuerats över analoga TV- och radionät och tagits emot av traditionella TV- och radioapparater, men detta håller på att ändras i och med att sändningarna digitaliseras och konvergens sker mellan broadcasting, telekom och datakom. Nu kan även andra terminaler fungera som mottagare, t.ex. en PC med ett digital-TVkort eller ett digital-radiokort. Digital TV och radio erbjuder tilläggstjänster som t.ex. ehandel, tjänster kopplade till radio- eller TV-program och elektroniska programguider. Om samma tjänst ska kunna tas emot på flera olika mottagarterminaler med olika egenskaper, måste tjänsten anpassas efter terminalerna. Detta kan göras genom att skala tjänsten, dvs. utseendet och funktionerna varierar beroende på bl.a. terminalens kapacitet. I detta arbete har terminalaspekterna på skalbara tjänster undersökts. Aktuella och framtida terminaler, plattformar och eventuella skalbarhetslösningar presenteras, och deras påverkan på skalbara tjänster diskuteras.</p>

<p>To efficiently examine volumetric data sets from CT or MRI scans good volume rendering applications are needed. This thesis describes the design and implementation of an application programming interface (API) to be used when developing volume-rendering applications. A complete application programming interface has been designed. The interface is designed so that it makes writing application programs containing volume rendering fast and easy. The interface also makes created application programs hardware independent. Volume rendering using 3d-textures is implemented on Windows and Unix platforms. Rendering performance has been compared between different graphics hardware.</p>