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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
651

Utveckling och konstruktion av analysatorverktyg för styrsignaler i HDMI-gränssnittet

Kaltea, Eddie, Lundgren, Daniel January 2009 (has links)
<p>Utveckling av produkter som skall stöda HDMI-standarden medför många hinder som behöver överkommas. Ett av problemen är certifiering mot standarden. Det är svårt att testa att standardens alla krav uppfylls på ett utvecklingsföretag då testutrustningen är kostsam och därför ej tillgänglig. Ett enkelt verktyg har därför utvecklats för att underlätta testning av att standarden följs.</p><p>Denna rapport inleds med en problemställning och grundläggande teori om relaterade ämnen. En förstudie följer sedan där olika sätt att lösa problemet presenteras. Sedan följer en övergripande beskrivning om hur verktyget fungerar och hur det tillverkades. I slutet på rapporten finns en efterstudie och resultat som beskriver hur verktygets utveckling har fungerat och hur resultatet från förstudien påverkat utvecklingen.</p><p>Resultatet av examensarbetet är en prototyp som går att använda för att underlätta testning av att HDMI-standarden följs i vissa avseenden.</p>
652

Evaluation of Cryptographic Packages

Raheem, Muhammad January 2009 (has links)
<p>The widespread use of computer technology for information handling resulted in the need for higher data protection.The usage of high profile cryptographic protocols and algorithms do not always necessarily guarantee high security. They are needed to be used according to the needs of the organization depending upon certain characteristics and available resources.The communication system in a cryptographic environment may become vulnerable to attacks if the cryptographic packages don’t meet their intended goals.</p><p>This master’s thesis is targeted towards the goal of evaluating contemporary cryptographic algorithms and protocols collectively named as cryptographic packages as per security needs of the organization with the available resources.</p><p>The results have shown that there certainly is a need for careful evaluations of cryptographic packages given with available resources otherwise it could turn into creating more severe problems such as network bottlenecks, information and identity loss, non trustable environment and computational infeasibilities resulting in huge response times. In contrast, choosing the right package with right security parameters can lead to a secure and best performance communication environment.</p>
653

Replacing OSE with Real Time capable Linux

Boman, Simon, Rutgersson, Olof January 2009 (has links)
<p>For many years OSE has been a common used operating system, with real time extensions enhancements, in embed-ded systems. But in the last decades, Linux has grown and became a competitor to common operating systems and, in recent years, even as an operating system with real time extensions. With this in mind, ÅF was interested in replacing the quite expensive OSE with some distribution of the open source based Linux on a PowerPC MPC8360. Therefore, our purpose with thesis is to implement Linux on the named platform and make some tests to see if it is possible to replace OSE with Linux. Using Linux has several advantages, for example it is free of charge to use and over the years the popularity of Linux within the developer community has resulted in numerous tools and utilities available for free.</p><p>As a result, this study shows that Linux with real time extensions on the MPC8360 PowerPC platform is a viable alternative to OSE regarding cost efficiency, flexibility, adaptability and competence available on the market.</p><p>Further studies can be done towards benchmarking for I/O systems and implementing support for more hardware on the MPC8360 AF platform.</p>
654

Säker lagring av krypteringsnycklar / Secure Storage of Encryption Keys

Hansson, Fredrik January 2009 (has links)
<p>Kryptering används för en mängd olika ändamål idag, till exempel för att elektroniskt signera dokument, autentisera en person och skydda hemlig information. För att detta skall fungera krävs att krypteringsnyckeln hålls hemlig och är lagrad på ett säkert sätt. Denna rapport redogör för hur krypteringsnycklar idag lagras och hur säkra det olika sätten är. Lagringssätten som behandlas är bland annat aktiva kort, bankdosor och datorfil. Det redogörs även för ett antal olika typer av hot såsom social engineering, malware och avlyssning för att slå fast vilka hot som är möjliga mot vilka system. Syftet med denna rapport är alltså att utvärdera hur säkra dagens sätt att lagra krypteringsnycklar är och vilka brister det finns med dessa. Syftet är även att få läsaren att förstå att hur man som användare beter sig spelar in på säkerheten i dessa system.</p><p>Det visar sig att alla de behandlade systemen har brister som gör att krypteringsnyckeln kan hamna i orätta händer. Vissa av systemen har fler och större brister än de andra. Säkrast verkar bankdosor och aktiva kort vara då de egentligen bara är möjligt att attackera dessa om bedragaren kan få fysisk kontakt till dem. Vid fysisk kontakt har dessutom alla systemen brister som gör det möjligt att få ut krypteringsnyckeln. Det leder till slutsatsen att det är viktigt att användaren hanterar sin utrustning på ett säkert sätt och förhindrar obehöriga att få fysisk tillgång till dem.</p><p> </p> / <p>Cryptology is used for a lot of different purposes today. For example it is used for sign electronic documents, to authenticate a person and to protect secret information. In order for this to be secure the encryption key has to be kept concealed and stored in a secure way. This paper discusses how encryption keys are stored today and how secure it is. It discusses authentication tokens, smart cards and encryption keys in computer files. It also discusses some threats, like social engineering, malware and eavesdropping in order to understand which threats are dangerous to which systems. The purpose of this paper is to evaluate how secure the key storage is and to point out the security flaws in the systems. Another purpose is to make the reader understand that the behavior of a user will affect the security of the systems.</p><p>All the discussed systems have security flaws which can lead to that the encryption key can end up in wrong hands. Some of the systems have larger flaws than others. The most secure systems seem to be authentication tokens and smart cards. It is only possible to attack those systems when physical access to the equipment can be obtained. Actually none of the discussed systems has good protection for physical access attacks. This leads to the conclusion that it is very important that a user handle his equipment in a secure way and prevent unauthorized persons to access them.</p><p> </p>
655

Modeling and algorithm adaptation for a novel parallel DSP processor / Modellering och algorithm-anpassning för en ny parallell DSP-processor

Kraigher, Olof, Olsson, Johan January 2009 (has links)
<p>The P3RMA (Programmable, Parallel, and Predictable Random Memory Access) processor, currently being developed at Linköping University Sweden, is an attempt to solve the problems of parallel computing by utilizing a parallel memory subsystem and splitting the complexity of address computations with the complexity of data computations. It is targeted at embedded low power low cost computing for mobile phones, handsets and basestations among many others. By studying the radix-2 FFT using the P3RMA concept we have shown that even algorithms with a complex addressing pattern can be adapted to fully utilize a parallel datapath while only requiring additional simple addressing hardware. By supporting this algorithm with a SIMT instruction almost 100% utilization of the datapath can be achieved. A simulator framework for this processor has been proposed and implemented. This simulator has a very flexible structure featuring modular addition of new instructions and configurable hardware parameters. The simulator might be used by hardware developers and firmware developers in the future.</p>
656

Standardisering av funktionsblock for PLC / Standardization of function blocks for PLC

Hultkrantz, Jörgen January 2009 (has links)
<p>Automationscenter & Bråvalla Elteknik AB is a company that offers the market completed total solutions where the customer can operate and monitor their production from the terminal. In these total solutions they lack standard circuit which are developed by the company and which could manoeuvre/control/monitor controlled process objects. This report defines the work of developing the most common standard circuits.The report is initiated by a short theoretical part about PLC and the PLC system, with a connected terminal, which has been used. Thereafter, the turnout of the demands of specification is reported, after discussing with the supervisor in the course of the project. The report concludes with a disclosure of how the programming, the documentation and the testing have proceeded and a final discussion concerning the project and proposals on continuation.The result is a CD with the documentation of standard circuits and how they are implemented in a new project. One library file with the program code to all standard circuit. Program code and documentation for both demonstration and testing are also on the CD. This project represents a start of POS (Process Objektsstyrnings Standard) as the collection is called at Automationscenter.</p> / <p>Automationscenter & Bråvalla Elteknik AB är ett företag som erbjuder marknaden färdiga totallösningar där kunden kan manövrera och övervaka sin produktion från operatörspaneler. I denna totallösning saknar företaget egna framtagna ”typkretsar” som manövrerar/kontrollerar/övervakar styrda processobjekt. En typkrets skall ha en del som implementeras i PLC och en del som implementeras i operatörspanelen.Denna rapport redogör för hur några av de vanligaste ”typkretsarna” tas fram.Rapporten inleds med en kort teoridel om PLC och det PLC‐system med tillhörande operatörspanel som använts. Därefter redogörs hur typkretsarnas kravspecifikation blev efter att ha diskuterat med handledaren under arbetets gång. Rapporten avslutas med en redovisning för hur programmeringen, dokumentationen och testningen gått till och en avslutande diskussion om arbetet och förslag på fortsättning.Resultatet blev en CD‐skiva med dokumentation om typkretsarna och hur de implementeras i ett nytt projekt: en biblioteksfil med programkoden till alla typkretsar. Programkod och dokumentation för både visning och testning finns också med på skivan. Ex‐jobbet utgör en början på POS Process Objektsstyrnings Standard som samlingen heter på Automationscenter & Bråvalla Elteknik AB.</p>
657

Testverktyg för programvara skriven i Ada

Lindh, Hanna January 2005 (has links)
<p>Syftet med den här rapporten är att undersöka om det finns något testverktyg som uppfyller kraven från Saab Underwater Systems. I rapporten presenteras även en sammanfattning av testningens grunder och metoder för att välja ut och utvärdera datorprogram. Arbetet med att välja ut och utvärdera testverktyg kan ses som en process. Först ska kraven sammanställas och sedan ska några verktyg väljas ut för utvärdering. Två av de tre verktyg som valdes ut utvärderades mer</p><p>ingående. De två testverktyg som utvärderades var LDRA Testbed och AdaTEST 95. LDRA Testbed har väldigt många olika statiska analyser vilket i många fall troligen inte kommer att utnyttjas. Enhetstestningen sker med hjälp av TBrun som är en del av verktygsserien som LDRA marknadsför. AdaTEST 95 har inte lika många funktioner som LDRA Testbed men har de nödvändiga statiska analyserna och enhetstestning presenterade i ett enklare gränssnitt. Båda</p><p>verktygen uppfyller de viktigaste kraven från Saab Underwater Systems, men inget av dem uppfyller alla krav. Båda verktygen skulle kunna underlätta testningen men AdaTEST 95 rekommenderas. AdaTEST 95 är framtaget för att underlätta för i första hand utvecklare och det är utvecklare som ska använda verktyget på Saab Underwater Systems.</p>
658

Measuring and Analysing Execution Time in an Automotive Real-Time Application / Exekveringstid i ett Realtidssystem för Fordon

Liljeroth, Henrik January 2009 (has links)
<p>Autoliv has developed the Night Vision system, which is a safety system for use incars to improve the driver’s situational awareness during night conditions. It is areal-time system that is able to detect pedestrians in the traffic environment andissue warnings when there is a risk of collision. The timing behaviour of programsrunning on real-time systems is vital information when developing and optimisingboth hardware and software. As a part of further developing their Night Visionsystem, Autoliv wanted to examine detailed timing behaviour of a specific part ofthe Night Vision algorithm, namely the Tracking module, which tracks detectedpedestrians. Parallel to this, they also wanted a reliable method to obtain timingdata that would work for other parts of that system as well, or even other applications.</p><p>A preliminary study was conducted in order to determine the most suitable methodof obtaining the timing data desired. This resulted in a measurement-based approachusing software profiling, in which the Tracking module was measured usingvarious input data. The measurements were performed on simulated hardwareusing both a cycle accurate simulator and measurement tools from the systemCPU manufacturer, as well as tools implemented specifically to handle input andoutput data.</p><p>The measurements resulted in large amounts of data used to compile performancestatistics. Using different scenarios in the input data, we were able to obtain timingcharacteristics for several typical situations the system may encounter duringoperation. By manipulating the input data we were also able to observe generalbehaviour and achieve artificially high execution times, which serves as indicationson how the system responds to irregular and unexpected input data.</p><p>The method used for collecting timing information was well suited for this particularproject. It provided the possibility to analyse behavior in a better waythan other, more theoretical, approaches would have. The method is also easilyadaptable to other parts of the Night Vision system, or other systems, with onlyminor adjustments to measurement environment and tools.</p>
659

Implementation of a Gigabit IP router on an FPGA platform

Borslehag, Tobias January 2005 (has links)
<p>The computer engineering group at Linköping University has parts of their research dedicated to networks-on-chip and components used in network components and terminals. This research has among others resulted in the SoCBUS NOC and a flow based network protocol processor. The main objective of this project was to integrate these components into an IP router with two or more Gigabit Ethernet interfaces.</p><p>A working system has been designed and found working. It consists of three main components, the input module, the output module and a packet buffer. Due to the time constraint and the size of the project the packet buffer could not be designed to be as efficient as possible, thus reducing the overall performance. The SoCBUS also has negative impact on performance, although this could probably be reduced with a revised system design. If such a project is carried out it could use the input and output modules from this project, which connect to SoCBUS and can easily be integrated with other packet buffers and system designs.</p>
660

Avkodning av streckkoder i mobila enheter

Stolt, Jonatan January 2009 (has links)
<p>The most common method for identifying merchandise in the commerce is by barcodes. Symbian OS is an advanced operating system aimed at cell phones and the most commonly used in smart phones. Opportunities to a full range of new services are given through barcode recognition in a Symbian OS based device. Therefore the purpose of this degree project was to create an application which would contribute to a future solution aimed at shopping where the cell phone constitutes a reader of itemsʼ identification numbers. Available barcode decoders have been evaluated and three were chosen for testing. The decoder that fared best was ZXing. It was subsequently incorporated into a Symbian OS-based mobile phone. The decoder was written in the Java language but sufficient Java APIs for controlling the camera's autofocus were missing, something that was necessary to decode the barcode. On the other hand the APIs were offered in C++. Therefore, the solution was split into two applications, one server application written in Java and responsible for the decoding and one client application written in C++ containing the GUI, camera controlling facilities and connections to two price comparison services. A procedure for communication between applications and an interface for various lookup services were defined. Finally, the information security was evaluated and the most relevant threat would be a third party that collects information about user behavior patterns for extortion purposes. It was concluded that the application that was created had the ability to scan barcodes, it is possible to extend and thereby fulfill the purpose.</p>

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