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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.
11

Ingénierie des exigences pour la conception d'architectures de sécurité de systèmes embarqués distribués / A requirement engineering driven approach to security architecture design for distributed embedded systems

Idrees, Muhammad Sabir 21 September 2012 (has links)
Au cours des dix dernières années, l’impact des questions de sécurité sur le développement et la mise en oeuvre des systèmes embarqués distribués n’a jamais cessé de croître. Ceci est principalement lié à l’interconnexion toujours plus importante de ces systèmes qui les rend vulnérables aux attaques, ainsi qu’à l’intérêt économique d’attaquer ces systèmes qui s’est simultanément accru. Dans un tel contexte, méthodologies et outils d’ingénierie des exigences de sécurité sont devenus indispensables pour prendre des décisions appropriées quant a` la sécurité, et ce le plus tôt possible. L’ingénierie des exigences devrait donc fournir une aide substantielle à l’explicitation et à la spécification des problèmes et solutions de sécurité des logiciels bien avant que concepteurs et développeurs ne soient engagés dans une implantation en particulier. Toutefois, et c’est particulièrement vrai dans les systèmes embarqués, les exigences de sécurité ne doivent pas être considérées seulement comme l’expression abstraite d’un ensemble de propriétés indépendamment de l’architecture système ou des menaces et des attaques qui pourraient y survenir. Nous estimons que cette considération est d’une importance capitale pour faire de l’ingénierie des exigences un guide et un moteur de la conception et de la mise en œuvre d’un système sécurisé. Notre approche s’appuie en particulier sur une approche centrée sur les connaissances de l’ingénierie des exigences de sécurité, applicable dès les premières phases de conception du système jusqu’à la mise en application des exigences de sécurité dans l’implantation. / During the last ten years, the impact of security concerns on the development and exploration of distributed embedded systems never ceased to grow. This is mainly related to the fact that these systems are increasingly interconnected and thus vulnerable to attacks, and that the economic interest in attacking them has simultane- ously increased. In such a context, requirement engineering methodologies and tools have become necessary to take appropriate decisions regarding security early on. Security requirements engineering should thus strongly support the elicitation and specifica- tion of software security issues and solutions well before designers and developers are committed to a particular implementation. However, and that is especially true in embedded systems, security requirements should not be considered only as the abstract expression of a set of properties independently from the system architecture or from the threats and attacks that may occur. We believe this consideration is of utmost importance for security requirements engineering to be the driving force behind the design and implementation of a secure system. We thus describe in this thesis a security engineering requirement methodology depending upon a constant dialog between the design of system functions, the requirements that are attached to them, the design and development of the system architecture, and the assessment of the threats to system assets. Our approach in particular relies on a knowledge-centric approach to security requirement engineering, applicable from the early phases of system conceptualization to the enforcement of security requirements.
12

An implementation of an autonomous IoT system for real-time water quality monitoring with 4G and satellite connection : CatFish - Embedded systems

Elfing, Johan, Persson, Daniel January 2022 (has links)
This thesis is about implementing an Internet of Things system for measuring water quality in rivers and other aquatic environments with an autonomous water drone, where the data from various components are collected and sent wirelessly to the database in real-time. A Raspberry Pi is connected to the internet through a 4G modem and a wireless satellite communication connection called RockBlock for emergency calls and notifications. In addition, a sonar is also implemented to collect data for the unmanned surface vehicle's (USV) avoidance of collisions. Finally, batteries are connected to solar panels to auto-generate energy and provide the USV with its requested current and voltage. The minimum parameters to measure water quality are four: potential hydrogen, dissolved oxygen, nitrates, and colored dissolved organic matter. As a result, the system in this thesis measures the four parameters mentioned above, plus turbidity and temperature, since the interconnected sensors can also measure those. In addition, optical sensors were chosen because of their exceptional accuracy and precision when measuring water quality. The environment, mainly the aquatic, will benefit from this project and change for the better with time. / Den här vetenskapliga artikeln handlar om att implementera ett Internet of Things system avsett för att mäta vattenkvaliteten i floder och andra vattenmiljöer med en autonom vattendrönare, där datan från diverse komponenter samlas in och skickas trådlöst till databasen i realtid. En Raspberry Pi är ansluten till internet via ett 4G-modem samt en trådlös satellitkommunikationsanslutning som kallas RockBlock för nödmeddelanden och notifikationer. Dessutom implementeras ett ekolod för insamling av data till den autonoma vattendrönaren för undvikande avkollisioner. Slutligen är batterierna anslutna till solcellspaneler för att automatiskt generera energi och förse den autonoma vattendrönaren med tillräcklig ström samt spänning.Det minsta antalet parametrar för att mäta vattenkvalitet är fyra: potentiellt väte, löst syre, nitrat, och färgat löst organiskt material. Som ett resultat mäter systemet i denna avhandling de fyra parametrarna nämnda ovan, plusgrumlighet och temperatur, eftersom de sammankopplade sensorerna ocksåkan mäta dessa. Dessutom valdes optiska sensorer på grund av deras exceptionella noggrannhet och precision vid vattenkvalitetsmätning. Miljön, speciellt vattenmiljön, kommer att gynnas av detta projekt samt förändras till det bättre med tiden.
13

Intelligente Himbeere - Der Raspberry Pi

Heik, Andreas, Sontag, Ralph 08 May 2013 (has links) (PDF)
Aus der Vision, Computertechnik für den schmalen Geldbeutel technisch interessierten Jugendlichen verfügbar zu machen entstand ein kreditkartengroßer Einplatinencomputer, der Raspberry Pi. Wir möchten den Raspi im Vortrag etwas näher vorstellen und in einer kleinen Demonstration Anregungen für eigene Projekte geben. Gespannt sind wir auch auf Projekte, welche die Zuhörer bereits mit dem Raspberry Pi umgesetzt haben.
14

ARM i inbyggt system : med prototyp / ARM in Embedded System : with Prototype

Abdulhadi, Sami January 2009 (has links)
Inbyggda system blir allt vanligare i dagens samhälle. De inbyggda systemen finns i nästan allt nuförtiden, från diverse fordon till leksaker för barn. Dagens teknik innebär bland annat att gårdagens lösningar kan realiseras på en bråkdel av den tidigare ytan. Allt mer blir ytmonterat med mindre och mer komplexa kretsar. Detta är inte alltid till utvecklarnas fördel då montering av prototypkort blir en svår och/eller dyr process. Målet är att ta fram ett inbyggt system med en ARM-processor. Systemet ska innehålla USB-OTG, ethernet, minne av olika slag som FRAM och microSD samt en display med pekskärm för användargränssnitt. Projektet omfattar allt från komponentval till test och verifiering med programkod. Tiden räckte inte till för att få med alla delar som planerats. Resultatet av projektet blev ett prototypkort och två små programsekvenser, en som blinkar två lysdioder på kortet och en som skriver ut en bild på displayen. Detta inbyggda system är i första hand till för utvärdering av ARM-processorer för Mikrodidakt AB. / Embedded systems has become more and more common in today's society. The embedded systems are included in almost everything today, from various vehicles to children's toys. Today's technology means that yesterday's solutions can be realised on a fraction of the area. More and more become surface mounted with smaller and more complex circuits. This is not always an advantage for the developers when assembling and soldering prototype circuit boards become a more difficult and/or an expensive process. The goal is to create an embedded system with an ARM-processor. The system will consist of USB-OTG, ethernet, various memory like FRAM and microSD and a display with touchscreen for user interface. The project includes everything from choice of components to test and verification with program code. The time was too short to include all the parts that was planned. The result of the project was a prototype card and two small program sequences, one that blinks the two light diodes on the card and one that writes a picture on the display. This embedded system is intended for evaluating ARM-processors by Mikrododakt AB.
15

THE STUDY OF EMBEDDED INTELLIGENT VEHICLE NAVIGATION SYSTEM*

Shengxi, Ding, Bo, Zhang, Jingchang, Tan, Dayi, Zeng 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / The intelligent vehicle navigation system is the multifunctional and complex integrate system that involved in auto positioning technology, geography information system and digital map database, computer technology, multimedia and wireless communication technology. In this paper, the autonomous navigation system based on the embedded hardware and embedded software platform is proposed. The system has advantages of low cost, low power consumption, multifunction and high stability and reliability.
16

Embedded vision system for intra-row weeding

Oberndorfer, Thomas January 2006 (has links)
<p>Weed control is nowadays a hi-tech discipline. Inter-row weed control is very sophisticated </p><p>whereas the intra-row weed control lacks a lot. The aim of this pro ject is to implement </p><p>an embedded system of an autonomous vision based intra-row weeding robot. Weed and </p><p>crops can be distinguished due to several attributes like colour, shape and context fea- </p><p>tures. Using an emebedded system has several advantages. The embedded system is </p><p>specialized on video processing and is designed to withstand the needs of outdoor use. </p><p>This embedded system is already able to distinguish between weed and crops. The per- </p><p>formance of the hardware is very good whereas the software still needs some optimizations.</p>
17

ARM i inbyggt system - med prototyp / ARM in Embedded System – with Prototype

Abdulhadi, Sami January 2009 (has links)
<p>Inbyggda system blir allt vanligare i dagens samhälle. De inbyggda systemen finns i nästan allt nuförtiden, från diverse fordon till leksaker för barn.</p><p>Dagens teknik innebär bland annat att gårdagens lösningar kan realiseras på en bråkdel av den tidigare ytan. Allt mer blir ytmonterat med mindre och mer komplexa kretsar. Detta är inte alltid till utvecklarnas fördel då montering av prototypkort blir en svår och/eller dyr process.</p><p>Målet är att ta fram ett inbyggt system med en ARM-processor. Systemet ska innehålla USB-OTG, ethernet, minne av olika slag som FRAM och microSD samt en display med pekskärm för användargränssnitt. Projektet omfattar allt från komponentval till test och verifiering med programkod.</p><p>Tiden räckte inte till för att få med alla delar som planerats. Resultatet av projektet blev ett prototypkort och två små programsekvenser, en som blinkar två lysdioder på kortet och en som skriver ut en bild på displayen.</p><p>Detta inbyggda system är i första hand till för utvärdering av ARM-processorer för Mikrodidakt AB.</p> / <p>Embedded systems has become more and more common in today's society. The embedded systems are included in almost everything today, from various vehicles to children's toys.</p><p>Today's technology means that yesterday's solutions can be realised on a fraction of the area. More and more become surface mounted with smaller and more complex circuits. This is not always an advantage for the developers when assembling and soldering prototype circuit boards become a more difficult and/or an expensive process.</p><p>The goal is to create an embedded system with an ARM-processor. The system will consist of USB-OTG, ethernet, various memory like FRAM and microSD and a display with touchscreen for user interface. The project includes everything from choice of components to test and verification with program code.</p><p>The time was too short to include all the parts that was planned. The result of the project was a prototype card and two small program sequences, one that blinks the two light diodes on the card and one that writes a picture on the display.</p><p>This embedded system is intended for evaluating ARM-processors by Mikrododakt AB.</p>
18

Architecture for Diagnostic Platform

Hedfors, Sara January 2010 (has links)
<p>In order to maximize operating time of an industrial machine and minimize stand-by time, service time and operating costs, a diagnostic system can be a useful tool. Diagnostic systems employ information already available in a machine’s control system (such as control signals, system state, sensor readings and so forth) to perform intelligent fault detection and localisation, and predict future faults and service needs.</p><p>CC Systems develops advanced electronics and control systems for industrial machines and vehicles operating in rough environments. One of their products is a diagnostic platform called Diagnostic Runtime Engine (DRE), supplying the customer with a tool for building a diagnostic system. The platform offers supervision of the control system. Actions are performed when it detects a possible fault or indication of a potential future fault. An action could be for example the creation of an alarm.</p><p>The DRE, as designed today, only works together with a control system running in an environment called CoDeSys. In this master thesis a new architecture of the platform is presented, with the objective to make the platform compatible with an arbitrary control system. A prototype is implemented to prove the concept of the suggested architecture model. A number of different standard diagnostic blocks, used for building the diagnostic system, are also suggested with the objective to make it easier for the user to employ the DRE. A proposition of how development with the diagnostic platform can proceed beyond this thesis is also presented.</p> / <p>För att maximera drifttid hos en industriell maskin och minimera driftskostnader samt standby- och service-tid, kan ett diagnostiksystem användas. Ett sådant system använder sig av information som redan finns tillgänglig i maskinens styrsystem (så som styrsignaler, tillstånd, sensorvärden och så vidare) för att utföra feldetektering och fellokalisering samt analys av möjliga framtida feltillstånd och servicebehov.</p><p>CC Systems utvecklar avancerade elektronikkomponenter och styrsystem för industriella maskiner och fordon. En av deras produkter är en diagnostikplattform, Diagnostic Runtime Engine (DRE), som erbjuder ett verktyg för att bygga upp ett diagnostiksystem. Plattformen möjliggör övervakning av styrsystemet, och detektion av ett nuvarande feltillstånd eller möjligt framtida feltillstånd leder till att en handling utförs. En handling kan till exempel vara att ett alarm skapas.</p><p>Diagnostikplattformen, som den är gjord idag, fungerar bara tillsammans med ett styrsystem som är implementerat i utvecklingsmiljön CoDeSys. I detta examensarbete presenteras en ny arkitektur på plattformen som möjliggör användande tillsammans med ett godtyckligt styrsystem. En prototyp är implementerad för att visa att den föreslagna arkitekturmodellen fungerar i praktiken. Dessutom är ett antal standard-diagnostikblock, som används då ett diagnostiksystem byggs upp, föreslagna. Standardblocken har till syfte att underlätta användandet av diagnostikplattformen. Ett förslag för hur DRE kan byggas om och utvecklas i framtiden är också presenterat.</p>
19

Software Verification for a Custom Instrument using VectorCAST and CodeSonar

Ward, Christina Dawn 01 May 2011 (has links)
The goal of this thesis is to apply a structured verification process to a software package using a set of commercially available verification tools. The software package to be verified is adapted from a project that was developed to monitor an industrial machine at the Oak Ridge National Laboratory and includes two major subsystems. One subsystem, referred to as the Industrial Machine Monitoring Instrument (IMMI), connects to a machine and monitors operating parameters using common industrial sensors. A second subsystem, referred to as the Distributed Control System (DCS), interfaces between the IMMI and a personal computer, which provides a human machine interface using a hyperterminal. Both the IMMI and DCS are built around Freescale’s MC9S12XDP microcontroller using CodeWarrior as the Integrated Development Environment (IDE). The software package subjected to the structured verification process includes the main C code with its header file and the code for its interrupt events for the IMMI as well as the main C code for the DCS and its interrupt events. The software package is exposed to the scrutiny of two verification tools, VectorCAST and CodeSonar. VectorCAST is used to execute test cases and provide results for code coverage based on statement and branch coverage. CodeSonar is used to identify issues with the code at compile time such as allocation/deallocation issues, unsafe functions, and language use problems. The results from both verification tools are evaluated and necessary changes made to the software package. The modified software is then tested again with VectorCAST and CodeSonar. The final verification step is downloading the modified code into the IMMI and DCS microcontrollers and testing the overall system to ensure the expected results are achieved with hardware that is developed to simulate realistic signals.
20

ECG compression for Holter monitoring

Ottley, Adam Carl 11 April 2007
Cardiologists can gain useful insight into a patient's condition when they are able to correlate the patent's symptoms and activities. For this purpose, a Holter Monitor is often used - a portable electrocardiogram (ECG) recorder worn by the patient for a period of 24-72 hours. Preferably, the monitor is not cumbersome to the patient and thus it should be designed to be as small and light as possible; however, the storage requirements for such a long signal are very large and can significantly increase the recorder's size and cost, and so signal compression is often employed. At the same time, the decompressed signal must contain enough detail for the cardiologist to be able to identify irregularities. "Lossy" compressors may obscure such details, where a "lossless" compressor preserves the signal exactly as captured.<p>The purpose of this thesis is to develop a platform upon which a Holter Monitor can be built, including a hardware-assisted lossless compression method in order to avoid the signal quality penalties of a lossy algorithm. <p>The objective of this thesis is to develop and implement a low-complexity lossless ECG encoding algorithm capable of at least a 2:1 compression ratio in an embedded system for use in a Holter Monitor. <p>Different lossless compression techniques were evaluated in terms of coding efficiency as well as suitability for ECG waveform application, random access within the signal and complexity of the decoding operation. For the reduction of the physical circuit size, a System On a Programmable Chip (SOPC) design was utilized. <p>A coder based on a library of linear predictors and Rice coding was chosen and found to give a compression ratio of at least 2:1 and as high as 3:1 on real-world signals tested while having a low decoder complexity and fast random access to arbitrary parts of the signal. In the hardware-assisted implementation, the speed of encoding was a factor of between four and five faster than a software encoder running on the same CPU while allowing the CPU to perform other tasks during the encoding process.

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