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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.
531

Simulation of a TCU Node on a Virtual CAN Bus

Viklander, Johan January 2016 (has links)
Electrical Control Units (ECUs) communicating on Controller Area Networks (CAN buses) are widely used in vehicle electrical systems. Being able to simulate these circuits and buses in a computer environment is beneficial during the development phase when access to test benches is limited and expensive. Simulations can also give a very detailed view of the entire system which in an ordinary lab setup would be practically impossible. BAE Systems Örnsköldsvik SIL Lab department works in the simulation environment CANoe supplied by Vector Informatik GmbH. BAE Systems have a simulation model of their central communication circuit. Unlike the less complicated circuits on the bus it cannot be integrated in the CANoe simulation environment. The less complicated nodes are modelled to usable extent but this is not possible with the central communication circuit. This report presents a possible solution to facilitate communication between the simulated ECU and the CANoe simulation environment under certain real-time constraints. A solution was achieved with a combination of an external program which handled shared memory with callback functions and Vector's Fast Data eXchange protocol (FDX).
532

VRA-PROGRAMVARA MED TILLHÖRANDE STYRELEKTRONIK

Söder, Robert, Liljerås, Magnus January 2013 (has links)
This thesis has been done at the Unversity of Örebro for Örebro University Hospital (USÖ). In our work we have developed a product for hearing tests to determine hearing thresholds of small children. Our product contains software and a control surface for controlling two separate screens. One of the demands was that our software could handle big file libraries. Reliability and simplicity were essential for the user. In our work we have utilized programming of both microcontrollers and Windows software. We have also connected the control surface with the software via serial communication. We have developed a prototype which can be seen as a finished product. Our product is safe for future use and compatible with newer versions of the Windows operating system. As of yet, it has not been tested in a real life setting.
533

Consolidating Automotive Real-Time Applications on Many-Core Platforms

Becker, Matthias January 2017 (has links)
Automotive systems have transitioned from basic transportation utilities to sophisticated systems. The rapid increase in functionality comes along with a steep increase in software complexity. This manifests itself in a surge of the number of functionalities as well as the complexity of existing functions. To cope with this transition, current trends shift away from today’s distributed architectures towards integrated architectures, where previously distributed functionality is consolidated on fewer, more powerful, computers. This can ease the integration process, reduce the hardware complexity, and ultimately save costs. One promising hardware platform for these powerful embedded computers is the many-core processor. A many-core processor hosts a vast number of compute cores, that are partitioned on tiles which are connected by a Network-on-Chip. These natural partitions can provide exclusive execution spaces for different applications, since most resources are not shared among them. Hence, natural building blocks towards temporally and spatially separated execution spaces exist as a result of the hardware architecture. Additionally to the traditional task local deadlines, automotive applications are often subject to timing constraints on the data propagation through a chain of semantically related tasks. Such requirements pose challenges to the system designer as they are only able to verify them after the system synthesis (i.e. very late in the design process). In this thesis, we present methods that transform complex timing constraints on the data propagation delay to precedence constraints between individual jobs. An execution framework for the cluster of the many-core is proposed that allows access to cluster external memory while it avoids contention on shared resources by design. A partitioning and configuration of the Network-on-Chip provides isolation between the different applications and reduces the access time from the clusters to external memory. Moreover, methods that facilitate the verification of data propagation delays in each development step are provided.
534

A Model-driven Development Approach with Temporal Awareness for Vehicular Embedded Systems

Bucaioni, Alessio January 2017 (has links)
Considering the ubiquitousness of software in modern vehicles, its increased value and development cost, an efficient software development became of paramount importance for the vehicular domain. It has been identified that early verification of non functional properties of  vehicular embedded software such as, timing, reliability and safety, is crucial to efficiency. However, early verification of non functional properties is hard to achieve with traditional software development approaches due to the abstraction and the lack of automation of these methodologies.   This doctoral thesis aims at improving efficiency in vehicular embedded software development by minimising the need for late, expensive and time consuming software modifications with early design changes, identified through timing verification, which usually are cheaper and faster. To this end, we introduce a novel model-driven approach which exploits the interplay of two automotive-specific modelling languages for the representation of functional and execution models and defines a suite of model transformations for their automatic integration.   Starting from a functional model (expressed by means of EAST-ADL), all the execution models (expressed by means of the Rubus Component Model) entailing unique timing configurations are derived. Schedulability analysis selects the set of the feasible execution models with respect to specified timing requirements. Eventually, a reference to the selected execution models along with their analysis results is automatically created in the related functional model to allow the engineer to investigate them.   The main scientific contributions of this doctoral thesis are i) a metamodel definition for the Rubus Component Model, ii) an automatic mechanism for the generation of Rubus models from EAST-ADL, iii) an automatic mechanism for the selection and back-propagation of the analysis results and related Rubus models to design level and iv) a compact notation for visualising the selected Rubus models by means of a single execution model.
535

System för insamling av väderdata / System for collecting weather data

Laurell, Isak, Sjöholm, Linus January 2017 (has links)
På försvarets materielverk (FMV) i Karlsborg utförs prover av militära vapensystem. Ofta när prov genomförs samlas också väderdata in för att veta om yttre faktorer kan påverka en träffbild. Insamling av väderdata är en manuell process som FMV önskar att automatisera. Målet är att skapa ett system med hjälp av en befintlig vädersensor som kan visa väderparametrar i realtid på en skärm samt spara dem vid rätt tillfälle på ett flyttbart media. Vid utveckling av system för insamling av väderdata ska det väljas ut lämplig hårdvara där även mjukvaran ska formas. Den teoretiska referensramen och litteraturstudierna utgjorde en bra grund för hela projektet genom att få en förståelse om alla de delar som måste tas hänsyn till. FMV har som krav att hårdvaran ska vara baserad på en integrerad krets. Det innebär kortfattat att det inte finns något operativsystem utan att det består endast av en källkod. Den befintliga vädersensorn som ska användas kommunicerar via seriell kommunikation. Det gjordes också ett val mellan två utvecklingsmodeller där en av dem senare ska användas som ett hjälpmedel för utvecklingsprocessen av hela systemet. Den utvecklingsmodell som var mest lämplig för projektet var V-modellen. Genom att använda V-modellen togs det fram en bra struktur för hur arbetet skulle läggas upp gällande planering, verkställande och testning. Med en detaljerad planering underlättade det verkställandet genom att det fanns en tydlig bild av vad som skulle göras. Den noga planeringen gjorde att fel och brister i systemet vid testerna var få. En nyckelfaktor för utvecklingsprocessen var också att ha ett bra samarbete med FMV:s personal vilket gjorde att utvecklingen följde deras vision om systemet. När utvecklingsprocessen och arbetet med V-modellen var genomfört var också ett system för insamling av väderdata framtaget och godkänt av FMV. Systemet generar en minskad hantering av data eftersom det utför det arbete som tidigare har varit manuellt. Det generar också stabilare mätvärden eftersom tidpunkten för loggningen blir mer exakt än tidigare.
536

Modeling and Optimization Frameworks for Runtime Adaptable Embedded Systems

Lizarraga, Adrian, Lizarraga, Adrian January 2016 (has links)
The widespread adoption of embedded computing systems has resulted in the realization of numerous sensing, decision, and control applications with diverse application-specific requirements. However, such embedded systems applications are becoming increasingly difficult to design, simulate, and optimize due to the multitude of interdependent parameters that must be considered to achieve optimal, or near-optimal, performance that meets design constraints. This situation is further exacerbated for data-adaptable embedded systems (DAES) applications due to the dynamic characteristics of the deployment environment and the data streams on which these systems operate. As operating conditions change, these embedded systems must continue to adapt their configuration and composition at runtime in order to meet application requirements. To assist both platform developers and application domain experts, this dissertation presents design and optimization frameworks for the synthesis of runtime adaptable embedded systems. For sensor network applications, we present an initial dynamic profiling and optimization platform that profiles network and sensor node activity to generate optimal node configurations at runtime based on designed-specified application requirements. To support a broader class of DAES applications, we present a modeling and optimization framework that supports the specification of application task flows, data types, and runtime estimation models for the runtime adaptation of task implementations and device mappings. Experimental results for these design and optimization frameworks demonstrate the benefits of dynamic optimization compared to static optimization alternatives. For the presented sensor network and video-based collision avoidance applications, dynamic configurations exhibited improvements of up to 109% and 76%, respectively. Moreover, the performance of the heuristic design space exploration (DSE) algorithms utilized by the runtime optimization frameworks is compared to exhaustive DSE implementations, resulting in speedups of up to 1662X and 544X for the same two applications, respectively.
537

Subsídios para a representação de arquiteturas de referência de sistemas embarcados / Contributions to the representation of reference architectures of embedded systems

Milena Guessi 27 February 2013 (has links)
Arquiteturas de referência são construídas por combinarem as melhores praticas, padrões, plataformas e componentes para a construção e padronização de sistemas de software de um determinado domínio. De fato, diversas arquiteturas de referência podem ser encontradas para o domínio de sistemas embarcados, motivadas principalmente pela importância e complexidade crescentes que esses sistemas de software vêm apresentando. Dentre as atividades para elaboração de uma arquitetura de referência, a descrição apropriada dessa arquitetura é essencial para permitir que ela seja de fato utilizada. Contudo, não há na literatura um consenso sobre qual a melhor maneira de descrever arquiteturas de referência do domínio de sistemas embarcados, os tipos de informação que devem ser capturados ou ainda o conjunto de pontos de vista que pode ser construído. Visando sistematizar e padronizar a representação de arquiteturas de referência de sistemas embarcados, este trabalho propõe o método ProSA-Re. O método baseia-se nos resultados de uma revisão sistemática conduzida sobre o assunto e estabelece um conjunto de atividades e diretrizes para a construção da representação de arquiteturas de referência de sistemas embarcados. O método também esclarece o ciclo de vida de arquiteturas de referência, de modo a auxiliar na manutenção e na evolução das representações construídas com o seu apoio. Para ilustrar o ProSA-Re, uma representação da arquitetura de referência de sistemas multiagentes locais foi elaborada. Em seguida, a realização de uma avaliação com especialistas da área de arquitetura de software e um estudo de caso com usuários dessa representação permitiram a identicação de vantagens e limitações desse método. Espera-se que os resultados alcancados nesta dissertação possam contribuir para o reúso do conhecimento arquitetural e o desenvolvimento mais eficiente de sistemas de software do domínio de sistemas embarcados / Reference architectures combine the best practices, standards, platforms, and components to standardize software systems of a given domain. In this sense, reference architectures can be found for embedded systems, motivated by the increasing importance and complexity that these systems must cope with. In particular, the representation of the reference architecture is an essential activity for it to be used in practice. However, there is no consensus in the literature on what is the best way to describe reference architectures of embedded systems, including what types of information should be captured in those descriptions and also the set of viewpoints that could be adopted. Thus, this work establishes ProSA-Re, a method for systematizing and standardizing the representation of reference architectures of embedded systems. ProSA-Re considers the results of a systematic review on this subject and species a set of viewpoints, concerns, tasks, and guidelines to describe reference architectures of embedded systems. ProSA-Re also supports the reference architectures\' life cycle by clarifying the evolution of architectural descriptions built with it. To illustrate the method, a representation for the reference architecture of situated multiagent systems was built. Then, a case study was conducted to evaluate the resulting representation and specialists were consulted to evaluate the method description. We hope with this method to further improve the reuse of architectural knowledge, thus contributing for the development of software systems in this domain
538

Trådlös datainsamling av maxeffekt hos PV-moduler av varierande ström- och spänningskarakteristik / Wireless MPP Data Logging for PV Modules of Varying Current and Voltage Characteristics

Liljeblad, Mio, Abdelmoumene, Youcef January 2020 (has links)
Syftet med projektet är att samla in data kring PV-modulers maxeffekt. Felmarginalen hos datan får vara högst ±2%. De PV-moduler som ska kopplas in har kortslutningsströmmar från 1.51A till 8.9A samt öppenkrets-spänningar från 15.7V till 98V. Ett IV-svep ska kunna genomföras och nya mätningar av maxeffekten ska skickas trådlöst var tionde sekund.  Automatisk kalibrering efter rådande ström- ochspänningskarakteristik kan initieras via applikationen Blynk, detta för att öka mätnoggrannheten till följd av det breda spann av PV-moduler mättekniken ska vara kompatibel med. Likaså kan en maxeffektföljande algoritm initieras via applikationen, där maxeffektens uppdateringsfrekvens ligger inom ett 10-sekundersintervall. IV-svep kan utföras med viss dataförlust närakortslutningsströmmen. Felmarginalen för spänningsmätningar uppgår till ±0.66% och felmarginalen för strömmätningar uppgår till ±1.23%. Felmarginalen för effekt uppgår till ±0.81% och felmarginalen för maxeffekt uppgår till ±0.89%. Data kan laddas ned som CSV-filer. Tester för de specifika PV-modulerna som ska kopplas in behöver genomföras. Ett annat val av OP-förstärkare kan förenkla kretsen. Resistansen hos Rshunt kan minskas för att öka det mätbara spänningsintervallet.
539

A Resource Efficient, HighSpeed FPGA Implementation of Lossless Image Compression for 3D Vision

Hinnerson, Martin January 2019 (has links)
High speed laser-scanning cameras such as Ranger3 from SICK send 3D images with high resolution and dynamic range. Typically the bandwidth of the transmission link set the limit for the operational frequency of the system. This thesis show how a lossless image compression system in most cases can be used to reduce bandwidth requirements and allow for higher operational frequencies. A hardware encoder is implemented in pl on the ZC-706 development board featuring a ZYNQ Z7045 SoC. In addition, a software decoder is implemented in C++. The encoder is based on the felics and jpeg-ls lossless compression algorithms and the implementation operate at 214.3 MHz with a max throughput of 3.43 Gbit/s. The compression ratio is compared to that of competing implementations from Teledyne DALSA Inc. and Pleora Technologies on a set of typical 3D range data images. The proposed algorithm achieve a higher compression ratio while maintaining a small hardware footprint.
540

Prestanda och precision på en enkortsdator i ett system med realtidskrav / Performance and precision of a single-board computer in a system with real-time requirements

Wikman, Torbjörn, Hassel, Philip January 2014 (has links)
The report aims to investigate how well a certain type of affordable embedded single board computer can hold up against today's more expensive computers in a computer system by doing various tests on a system with the specified requirements. The system has a Raspberry Pi as the single board computer which task is to control a camera based on coordinates obtained from a server as well as capture and stream a video signal on a network. The researches were conducted to check how much network traffic a single-chip computer sent in different video formats and how much CPU utilization was required. Studies were also made to ensure the accuracy of the camera control. The researches have been experimental, where several tests have been performed and analyzed. The results show that a sufficiently good accuracy can be obtained from the camera steering unit, in which two different servos have been investigated. When the video format MJPEG and H.264 are used, the single-chip computer is able to transmit a video signal up to 1280x720 at 15 fps. The system managed to download and perform calculations on an object from the server at 42.3 ms. When the entire system was up and running at the same time the Raspberry Pi didn’t manage to deliver a video signal and obtain the coordinates from the server fast enough. Depending on the video format the performance on the single-chip computer varied, but no setup managed to keep the system stable enough to reach the requirements. / Rapportens syfte är att undersöka hur väl en viss typ av billigare enkortsdator kan stå sig mot dagens dyrare datorer i ett datorsystem genom att göra olika undersökningar på ett system med uppsatta krav. Systemet har en Raspberry Pi som enkortsdator och har till uppgift att styra en kamera utifrån koordinater som fås från en server samt fånga och strömma en videosignal ut på ett nätverk. De undersökningar som gjordes var att kontrollera hur mycket nätverkstrafik som enkortsdatorn sände vid olika format på videosignalen samt hur mycket CPU- utnyttjande som krävdes. Undersökningar gjordes också för att säkerställa precisionen på kamerastyrningen. Alla undersökningar har varit experimentella, där flera olika tester har utförts och analyserats. Resultatet från undersökningarna visar att en tillräckligt god precision kan fås från kamerastyrningen, där två olika servon har undersökts. När videoformaten MJPEG och H.264 används kan enkortsdatorn klara av att sända ut en videosignal upp till 1280x720 med 15 bildrutor per sekund. I systemet som testerna utfördes på klarade enkortsdatorn av att hämta och utföra beräkningar på ett objekt från servern på 42,3 ms. När hela systemet var igång samtidigt klarade dock inte Raspberry Pi av att leverera en videosignal och hämta koordinater från servern tillräckligt snabbt. Beroende på vilket videoformat som användes presterade enkortsdatorn olika bra, men det var ingen inställning som stabilt klarade av att nå kraven.

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