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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.
121

A System for Driver Identity Verification

Hagemann, Andreas, Björk, Hanna January 2005 (has links)
<p>Different security issues are a top subject around the world, especially since the terror threats seem to intensify. In the same time, the transport industry suffer from problems with smuggling and theft of valuable goods. One way to increase the security might be to have a verification system installed in commercial trucks, in order to assure that the driver is the proper one.</p><p>This thesis has two purposes. One is to find appropriate methods for driver verification and build a prototype of a verification system which can be used for testing and further development. The other is to study how truck drivers perceive such a system and how their conception goes along with the growing demand for higher security. The present work is the result of a cooperation between an engineer and a cognitive scientist. The thesis focuses on the transport industry and was performed for Volvo Technology Corporation (VTEC), Gothenburg, Sweden.</p><p>Eleven available verification methods were studied. To enable a well-based selection of methods to implement in the prototype, inquiries and interviews with truck drivers and haulage contractors were carried out to complement the theoretical study. </p><p>One regular and three biometric verification methods were chosen for the test; fingerprint verification, face recognition, voice recognition and PIN verification. These methods were put together to a prototype system that was implemented in a truck simulator. A graphical user interface was developed in order to make the system user friendly. The prototype system was tested by 18 truck drivers. They were thoroughly interviewed before and after the test in order to retrieve their background, expectations and opinions as well as their perceptions and experiences of the test. </p><p>Most of the test participants were positive to the prototype system. Even though they did not feel a need for it today they believed it to “be the future”. However, some participants felt uncomfortable with the system since they felt controlled by it. It became clear how important it is to have a system that respect the users’ privacy and to assure that the users are well informed about how the system is used. Some of the technology used for the verification system requires more development to fit in the automotive context, but it is considered to be possible to achieve a secure and robust system.</p>
122

Simulation and synchronization of distributed real-time systems / Simulering av distribuerade realtids system i Stateflow och TrueTime

Leuhusen, Joakim, Karlsson, Andreas January 2010 (has links)
<p>Today we are very much dependent on different kinds of real time systems. Usually,a real time system is a system which is interacting with a physical environmentwith sensors or activators. There are many advantages by replacing mechanicalcomponents with electrical ones. For instance, it is usually cheaper and possibleto add new functions to the device without replacing the electronic part, whichwould have been necessary with a mechanical one.The possibility of simulating a distributed system is used throughout the vehi-cle industry. With the simulation of connected sub systems, using modeled busesand real time kernels, one could increase the correctness of the behavior of the sys-tem and consequently decrease the amount of time spent later in the developingprocess.In this master thesis we used modeled CAN-buses and real time models tosimulate the connection and execution time of the systems. The simulation resultsare used to validate the functionality of the distributed system. Additionally, aworst-case response time analysis is made to set timing constraints on the systemto fulfill given deadlines.During the work, different settings of the network are tested to analyze thesystem frequency needed to sustain deadlines and correctness on the network.</p>
123

Utvärdering och implementering av automatiska farthållare i fordonssimulator

Borst, Rikard January 2006 (has links)
<p>Vehicle simulators are becoming more common in vehicle industries. Company earns lot of money on simulations instead of real tests. Real tests are necessary but not made so extensively as before.</p><p>In this thesis the building of an vehice simulator will be described and a comparison between three different cruise controls. The three cruise controls are PI-regulator, a regulator who regulates after positions in the terrain and a MPC-regulator. The reason for choosing this three is to see the difference between simple regulation and more complex regulation with respect to fuel consumption, travel time and complexity.</p><p>The vehicle simulator is made in Matlab/Simulink, Visual Studio and Open Scene Graph. The facilities needed for runnning the simulator is a relative good computer with a grapics card on at least 128 MB RAM plus a steering wheel and pedals for brake and gas to achieve best feeling. A keyboard can be used but it reduces almost all feeling.</p><p>After several simulations a conclusion was made. The MPC-regulator was the regulator who consumed least fuel and travel time. The regulator who regulates after positions in the terrain was not too far away. It would be interesting to do more research about it. In fact it is only a PI-regulator who makes ``clever'' decisions when a hill with enough slope appears. With enough slope means a downhill where the vehicle can accelerate without the use of fuel and an uphill where the vehicle can not keep its speed with maximum use of fuel.</p><p>A conclusion was stated that the friction and height profile influenced on settings for the PI-regulator and with some adjustments on this settings, fuel could be saved.</p>
124

Smart Cylinder : Konceptstudie samt demonstrator för systemövervakning av hydraulcylindrar

Wiklund, Johan, Åkesson, Johan January 2006 (has links)
<p>Detta examensarbete har utförts på Institutionen för Konstruktions- och Produktionsteknik, avdelningen för Fluid och Mekanisk Systemteknik vid Linköpings Universitet, på uppdrag av CA-Verken AB i Sävsjö.</p><p>Arbetet är ett första steg i utvecklingen av en ny typ av hydraulcylinder med inbyggd tillståndsövervakning. Arbetet har bestått av en teoretisk studie kring system- och hälsoövervakning av hydraulcylindrar samt konstruktion av en demonstrator, en testrigg, för att testa och verifiera slutsatserna från den teoretiska studien. Studien och demonstratorn har resulterat i ett flertal förslag till hur en framtida produkt skall utformas.</p> / <p>This master thesis work is done at the Department of Mechanical Engineering, the division of Fluid and Mechanical Engineering Systems at Linköpings University in cooperation with CA-Verken AB in Sävsjö.</p><p>The thesis is the first step into the development of a new kind of hydraulic cylinder, a hydraulic cylinder with built-in system monitoring capabilities. The thesis work has been consisting of a theoretical concept analysis of system and health monitoring in hydraulic cylinders and construction of a demonstrator, a hydraulic test rig, in which the ideas and conclusion from the theoretical study are to be verified. The concept analysis along with the construction of the demonstrator has resulted in several suggestions how to design the future hydraulic cylinder.</p>
125

Utveckling av trigger för synkronisering av elektroniksystem : En praktisk tillämpning i elektroniksystem

Lundqvist, Mikael January 2006 (has links)
<p>De triggers som idag används i Autoliv BKIs laboratorium har till uppgift att synkronisera signalerna vid simulering av krock som en intern kvalitetskontroll av produktionen. De sköter utösning av airbags och start av höghastighetskameror.</p><p>Då Autoliv har flera modeller av krockkuddar används idag olika triggers och man har därför som önskemål att utveckla ett nytt system som skulle kunna ersätta de nuvarande systemen och som kan användas vid samtliga kvalitetstest.</p><p>Projektet resulterade i en testad prototyp som inkluderar hårdvara, mjukvara, samt CAD-ritningar till en färdig produkt.</p>
126

Kartering med autonomt fordon / Mapping using an autonomous vehicle

Karlsson, Andreas January 2006 (has links)
<p>För att mobila robotar skall kunna arbeta strukturerat krävs det att de har kännedom om hur omgivningen ser ut. Omgivningen kan antingen vara förprogrammerad eller så görs roboten självlärande. På Saab Bofors Dynamics i Linköping arbetas det med en mobil testplattform kallad Freke, som används för att bland annat utveckla och utvärdera navigeringslösningar. Intresse fanns för att vidareutveckla plattformen och få den att klara arbeta i okända miljöer. Ett första steg mot detta mål var att få systemet att kunna rita upp en egen karta utan tidigare kännedom om dess omgivningar.</p><p>Uppgiften för det här examensarbetet blev därför att utveckla och implementera ett autonomt system som klarar att navigera och utforska en begränsad omgivning samt att rita upp en karta över densamma. Under litteraturstudien hittades inte någon färdig lösning som gick att applicera på den givna plattformen. Lösningen på uppgiften blev istället att utveckla ett eget system, direkt anpassat för den aktuella plattformen. Hela systemet utvecklades från grunden och implementerades till en praktiskt fungerande lösning.</p><p>Plattformen som används består av ett fordonschassi med tre hjul, varav två är drivande och utrustade med pulsgivare som används för att beräkna hur fordonet kör. Plattformen är även utrustad med ultraljudssensorer för att kunna mäta avstånd till närliggande hinder och väggar runt fordonet. Navigeringen sker genom att fordonet följer väggar och detekterar korsningar och öppningar som det senare kan återvända till och utforska vidare. Resultatet av karteringen genereras som en png-bild.</p><p>Med den begränsade hårdvara som fanns att tillgå hölls förväntningarna på arbetet relativt låga med ett mål att få fram en tolkningsbar karta. Resultatet blev långt över förväntan med tydliga skalenliga kartor som visar detaljer som ingen trodde skulle synas i resultatet.</p>
127

Structural Algorithms in Rodon : with a prototype implementation in Java

Särnholm, Oskar January 2007 (has links)
<p>As machines are increasingly used to fulfill even more needs of mankind, the dependence upon those machines increase. To prevent catastrophic failure and to facilitate maintenance a diagnostic system can be used. A diagnostic system supervises the system and can alarm the operator when a fault has occurred, and possibly determine what the cause may be. One architecture of a diagnostic system is a number of tests run by an on-board computer checking certain combinations of sensor values and control signals chosen in advance. To design these tests is a difficult task, which leads to the desire to automate the test construction. A part of this task can be performed using structural methods.</p><p>In this thesis model based diagnosis is considered. This means that a formal mathematical model is used. The models typically consist of a number of equations describing the behavior of the system. In structural methods it is only considered if a variable exists in an equation or not. The goal of this master thesis project has been to apply structural methods to RODON models. RODON is a software diagnostics tool brought to market by Sörman Information & Media, which can perform various diagnostic-related tasks based on a single model. This model is defined in an object oriented fashion using a Modelica-like language called Rodelica. A prototype implementation of a structural algorithm plug-in has been developed and integrated into RODON. An additional part of the project has been to investigate further possible uses of structural algorithms in RODON, apart from diagnostic test construction. This has been performed as a series of interviews with Sörman and university employees.</p><p>The work performed in this thesis has shown that it is possible to apply structural methods to RODON models. It has also shown that even a prototype implementation can handle quite large systems. Some problems have been found as well, most notably in extracting a structural model from a RODON model. A consequence is that the developed structural plug-in only works for a subset of RODON models. It might be possible to deal with these problems if more time would be spent on the task. Finally, the interview survey revealed other possible uses of structural methods in RODON, including optimal sensor placement analysis and isolability and detectability analysis.</p>
128

Heat Pump System using Waste Energy for a District Heating Application

Vivas, David January 2008 (has links)
<p>Nowadays, reducing energy usage as well as reducing environmental impacts due to energy efficiency measurements is very common in the industrial sector. The objective of these measurements is to achieve better sustainable energy systems.</p><p>Sandvik Materials Technology (SMT) AB, one of the business areas of the enterprise Sandvik AB, is not an exception in that field.</p><p>The aim of this thesis project is to analyze how to use waste energy from the cooling of a steel plant for an internal district heating (DH) system within the industrial area of SMT AB located in Sandviken, Sweden. In order to reduce the energy use, the economic cost and the environmental impacts within the industrial area.</p><p>In order to achieve the aim has been studied the heat pump devices as the system to transfer the waste heat from the cooling of the steel plant to the DH system. Therefore, after the introduction to the project (part 1: Introduction) and the explanation of the aim</p><p>(part 2: Aim, methodology and delimitations), the basics of the heat pumps are studied and explained (part 3: Heat pumps theoretical study). After that, the knowledge acquired in part 3 is applied to define and calculate the heat pump system which fulfill the required</p><p>objectives achieving the greatest energy, economical and environmental impacts reductions (part 4: Heat pump practical study).</p><p>The achieved results show that there is a great opportunity to reduce the energy use within the industrial area (until 45300 MWh per year), the economical cost (until 2 millions euros per year) and the 2 CO emissions (until 2.3 millions of 2 CO kg per year1).</p><p>Therefore, the conclusion is that it must be taken into account to build the heat pump system and also that the effort of finding possible energy efficiency measurements within the industrial sector must be one priority for all the industrial companies, not only because the possible potential economical reductions, but also because of the potential environmental impacts reductions.</p>
129

System Level Techniques for Verification and Synchronization after Local Design Refinements

Raudvere, Tarvo January 2007 (has links)
Today's advanced digital devices are enormously complex and incorporate many functions. In order to capture the system functionality and to be able to analyze the needs for a final implementation more efficiently, the entry point of the system development process is pushed to a higher level of abstraction. System level design methodologies describe the initial system model without considering lower level implementation details and the objective of the design development process is to introduce lower level details through design refinement. In practice this kind of refinement process may entail non-semantic-preserving changes in the system description, and introduce new behaviors in the system functionality. In spite of new behaviors, a model formed by the refinement may still satisfy the design constraints and to realize the expected system. Due to the size of the involved models and the huge abstraction gap, the direct verification of a detailed implementation model against the abstract system model is quite impossible. However, the verification task can be considerably simplified, if each refinement step and its local implications are verified separately. One main idea of the Formal System Design (ForSyDe) methodology is to break the design process into smaller refinement steps that can be individually understood, analyzed and verified. The topic of this thesis is the verification of refinement steps in ForSyDe and similar methodologies. It proposes verification attributes attached to each non-semantic-preserving transformation. The attributes include critical properties that have to be preserved by transformations. Verification properties are defined as temporal logic expressions and the actual verification is done with the SMV model checker. The mapping rules of ForSyDe models to the SMV language are provided. In addition to properties, the verification attributes include abstraction techniques to reduce the size of the models and to make verification tractable. For computation refinements, the author defines the polynomial abstraction technique, that addresses verification of DSP applications at a high abstraction level. Due to the size of models, predefined properties target only the local correctness of refined design blocks and the global influence has to be examined separately. In order to compensate the influence of temporal refinements, the thesis provides two novel synchronization techniques. The proposed verification and synchronization techniques have been applied to relevant applications in the computation area and to communication protocols. / QC 20100816
130

Architecting and Modeling Automotive Embedded Systems

Larses, Ola January 2005 (has links)
Dealing properly with electronics and software will be a strong competitive advantage in the automotive sector in the near future. Electronics are driving current innovations and are at the same time becoming a larger part of the cost of the vehicle. In order to be successful as an automotive manufacturer, innovations must be introduced in the vehicle without compromising the final price tag. Also, the electronics has to compete with, and win over, the dependability of well known and proven mechanical solutions. Structure related costs can be reduced by designing a modular system, volume related costs can be reduced by utilizing fewer electronic control units that shares software performing a variety of functions. To achieve a modular system careful consideration must be applied in the architecture design process. Architecting is commonly referred to as an art, performed in a qualitative manner. This thesis provides a quantitative method for architecture design and evaluation targeting modular architectures. The architecture design method is based on a simple underlying information model. This model is extended through practical experiences in case studies to include support for configuration and documentation. An information model is a key enabler for managing the increasing complexity of automotive embedded systems. The model provides the basis for establishing the analyzable documentation that is required to ensure the dependability of the systems, specifically in terms of need for reliability, maintainability and safety. An information model supports traceability both within the product, across components, and also between different organizational units using different views of the product throughout the lifecycle. Further, some general issues of systems engineering and model based development related to the engineering of automotive embedded systems are discussed. Considerations for introducing a model based development process are covered. Also, the maturity of development processes and requirements on tools in an automotive context are evaluated. The ideas and methods presented in this thesis have been developed and tried in an industrial setting through a range of case studies. / QC 20101027

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