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  • 301.
    Neander, Jonas
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Nolin, Mikael
    Björkman, Mats
    Using Existing Infrastructure as Proxy Support for Sensor Networks2004Conference paper (Refereed)
  • 302.
    Neander, Jonas
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Sjödin, Mikael
    Mälardalen University, Department of Computer Science and Electronics.
    Björkman, Mats
    Mälardalen University, Department of Computer Science and Electronics.
    Svensson, Stefan
    ABB AB, Västerås, Sweden .
    Lennvall, Tomas
    ABB AB, Västerås, Sweden .
    Wireless Vibration Monitoring (WiVib) - An Industrial Case Study2007In: IEEE International Conference on Emerging Technologies and Factory Automation, ETFA, 2007, p. 920-923Conference paper (Refereed)
    Abstract [en]

    Testing in realistic environments is often overlooked in the early development of new technology. This paper describes a test to evaluate the whole chain from an accelerometer mounted on a motor to a sensor node sending wireless data to an access point. A pilot gives a great opportunity to get input from end-users (which could be very useful at the initial stages of a project), and provide potential contacts for next pilots.

    The goal of the pilot was to get a better understanding of the targeted environment and possible interference It may also lead to the discovery of issues not yet thought of, issues important for the resulting design of the end product.

  • 303.
    Ni, Pengpeng
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Isovic, Damir
    Mälardalen University, Department of Computer Science and Electronics.
    Fohler, Gerhard
    University of Kaiserslautern, Kaiserslautern, Germany.
    User-friendly H.264/AVC for Remote Browsing2006In: Proceedings of the International ACM Multimedia conferance (ACM 06), Santa Barbara, California, USA, 2006, p. 643-646Conference paper (Refereed)
    Abstract [en]

    With the growing popularity of variable network technologies, it is highly desirable to enable effective and quick browsing of remote multimedia content. In this paper we present a method for quick access of remote video content as an initial step towards a full digital Video Cassette Recording functionality in multimedia streaming applications such as Video-On-Demand, video broadcasting and remote video editing.We propose a transcoding scheme for H.264/AVC video that fully utilizes the benefits of recently proposed SP- and SI-frames to facilitate user-friendly remote stream browsing and editing. The transcoding parameters can be adaptively changed and optimized to support different characteristics of H.264 video streams.

  • 304.
    Nilsson, Markus
    Mälardalen University, Department of Computer Science and Electronics.
    Retrieve and Classify2005Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    Diagnostics based on time series are sometimes difficult to perform, particularly when the time series is continuous and non-stationary, i.e. they seldom contain recurring patterns which makes it difficult to identify similarities with other time series. This doctoral thesis presents an artificial intelligence approach to the analysis of continuous non-stationary signals for diagnostic purposes. One way to solve this kind of problem is to break down the series into new forms that are more easily interpreted, and to identify familiar patterns within them. The newly formed series is analysed, using the Case-Based Reasoning paradigm. Known problemsolution pairs are stored in memory and reused for solving problems by classifying new patterns occurring in time series obtained subsequently. Reasoning is conducted on the basis of the knowledge available and a best-guess solution obtained using the available knowledge is presented. The memory need not therefore contain a problem, which has been solved previously and is identical with the problem which is to be solved. This approach to problem solving has been applied to physiological time series as a clinical decision support system. The system provides decision support by classifying patterns of respiratory sinus arrhythmia from heart rate and capnography time series.

  • 305.
    Nilsson, Markus
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Funk, Peter
    Mälardalen University, Department of Computer Science and Electronics.
    A Case-Based Classification of Respiratory Sinus Arrhythmia2004In: Advances in Case-Based Reasoning, 2004, p. 673-685Conference paper (Other academic)
    Abstract [en]

    Respiratory Sinus Arrhythmia has until now been analysed manually by reviewing long time series of heart rate measurements. Patterns are identified in the analysis of the measurements. We propose a design for a classification system of Respiratory Sinus Arrhythmia by time series analysis of heart and respiration measurements. The classification uses Case-Based Reasoning and Rule-Based Reasoning in a Multi-Modal architecture. The system is in use as a research tool in psychophysiological medicine, and will be available as a decision support system for treatment personnel.

  • 306.
    Nilsson, Markus
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Funk, Peter
    Mälardalen University, Department of Computer Science and Electronics.
    Olsson, Erik. M. G.
    von Schéele, Bo
    Xiong, Ning
    Mälardalen University, Department of Computer Science and Electronics.
    Clinical decision support for diagnosing stress related disorders by applying psychophysiological medical knowledge to an instance based learning system2006In: Artificial Intelligence in Medicine, ISSN 0933-3657, E-ISSN 1873-2860, Vol. 36, no 2, p. 159-176Article in journal (Refereed)
    Abstract [en]

    Objective: An important procedure in diagnosing stress-related disorders caused by dysfunction in the interaction of the heart with breathing, i.e., respiratory sinus arrhythmia (RSA), is to analyse the breathing first and then the heart rate. Analysing these measurements is a time-consuming task for the diagnosing clinician. A decision-support system in this area would reduce the analysis task of the clinician and enable him/her to give more attention to the patient. We have created a decision-support system which contains a signal classifier and a pattern identifier. The system performs an analysis of the physiological time series concerned which would otherwise be performed manually by the clinician. Methods: The signal-classifier, HR3Modul, classifies heart-rate patterns by analysing both cardio- and pulmonary signals, i.e., physiological time series. HR3Modul uses case-basedreasoning (CBR), using a wavelet-based method for retrieving features from the signals. The system searches for familiar shapes in the signals by comparing them with shapes already stored. We have applied a best fit scheme for handling signals of different lengths, as the length of a breath is highly dynamic. We also apply automatic weighting to the features to obtain a more autonomous system. The classified heart signals indicate if a patient may be suffering from a stress-related disorder and the nature of the disorder. These classified signals are thereafter sent to the second subsystem, the pattern-identifier. The pattern-identifier analyses the classified signals and searches for familiar patterns by identifying sequences in the classified signals. The identified sequences give clinicians a more complete analysis of the measurements, providing them with a better basis for diagnosis. Results and conclusion: We have shown that a case-based classifier with a wavelet feature extractor and automatic weighting is a viable option for building a decision-support system for the psychophysiological domain, as it is at par, or even outperforms other retrieval techniques and is less complex.

  • 307.
    Nilsson, Markus
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Funk, Peter
    Mälardalen University, Department of Computer Science and Electronics.
    Sollenborn, Mikael
    Complex Measurement Classification in Medical Applications Using A Case-Based Approach2003In: Workshop proceedings of the fifth international conference on case-based reasoning, NTNU, Trondheim, Norway, 2003, p. 63-72Conference paper (Other academic)
  • 308.
    Nilsson, Markus
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Sollenborn, Mikael
    Mälardalen University, Department of Computer Science and Electronics.
    Advancement and Trends in Medical Case-Based Reasoning: An Overview of Systems and System Development2004In: Proceedings of the Seventeenth International Florida Artificial Intelligence Research Society Conference, FLAIRS 2004, 2004, p. 178-183Conference paper (Other academic)
    Abstract [en]

    Case-Based Reasoning (CBR) is a recognised and well established method for building medical systems. In this paper, we identify strengths and weaknesses of CBR in medicine. System properties, divided into construction-oriented and purpose-oriented, are used as the basis for a survey of recent publications and research projects. The survey is used to find current trends in present medical CBR research.

  • 309.
    Nolte, Thomas
    Mälardalen University, Department of Computer Science and Electronics.
    Reducing Pessimism and Increasing Flexibility in the Controller Area Network2003Licentiate thesis, monograph (Other scientific)
    Abstract [en]

    The Controller Area Network (CAN) is a widely used real-time communication network for automotive and other embedded applications. As new applications continue to evolve, the complexity of distributed CAN based systems increase. However, CAN's maximum speed of 1 Mbps remains fixed, leading to performance bottlenecks. In order to make full use of this scarce bandwidth, methods for increasing the achievable utilisation are needed. Traditionally, real-time scheduling theory has targeted hard real-time systems, which most of the time are safety critical. Since these systems (by definition) are not allowed to have any timing flaws, analysis techniques need to take all possible scenarios of execution combinations and execution times of the system into consideration. This will result in a system that is configured for the worst possible scenario. Whether this scenario is likely, or even possible, in the real system is not considered. Hence, the result may be an unnecessarily expensive system, with potentially overly provisioned resources. In this thesis we address two issues. In the first part, we investigate how to loosen up pessimistic real-time analysis in a controlled way, thereby allowing the designer to make well-founded trade-offs between the level of real-time guarantee and the system cost. Specifically, we investigate and model the bit-stuffing mechanism in CAN in order to retrieve representative distributions of stuff-bits, which we then use in the response time analysis instead of the worst-case values normally used. We evaluate the validity of these stuff-bit distributions in two case studies, and we integrate this representation of message frame length with the classical CAN worst-case response-time analysis. In the second part of the thesis, we propose a novel way of scheduling the CAN. By providing server-based scheduling, bandwidth isolation between users is guaranteed. This increases the flexibility of CAN, by providing efficient handling of sporadic and aperiodic message streams. Server-based scheduling also has the potential to allow higher network utilisation compared to CAN's native scheduling. The performance and properties of server-based scheduling of CAN is evaluated using simulation. Also, the server-based scheduling is applied in an end-to-end analysis. Keywords: controller area network, CAN, real-time communication, real-time analysis, reliability trade-off analysis, bit-stuffing, server-based scheduling

  • 310.
    Nolte, Thomas
    Mälardalen University, Department of Computer Science and Electronics.
    Share-Driven Scheduling of Embedded Networks2006Doctoral thesis, monograph (Other scientific)
    Abstract [en]

    Many products are built from more or less independently developed subsystems. For instance, a car consists of subsystems for transmission, braking, suspension, etc. These subsystems are frequently controlled by an embedded computer system. In the automotive industry, as well as in other application domains, there is currently a trend from an approach where subsystems have dedicated computer hardware and other resources (a federated approach) to an approach where subsystems share hardware and other resources (an integrated approach). This is motivated by a strong pressure to reduce product cost, at the same time as an increasing number of subsystems are being introduced.

    When integrating subsystems, it is desirable that guarantees valid before integration are also valid after integration, since this would eliminate the need for costly reverifications. The computer network is a resource that is typically shared among all subsystems. Hence, a central issue when integrating subsystems is to provide an efficient scheduling of message transmissions on the network. There are essentially three families of schedulers that can be used: priority-driven schedulers that assign priorities to messages, time-driven schedulers that assign specific time-slots for transmission of specific messages, and share-driven schedulers that assign shares of the available network capacity to groups of messages.

    This thesis presents a framework for share-driven scheduling, to be implemented and used in embedded networks, with the aim to facilitate subsystem integration by reducing the risk of interference between subsystems. The framework is applied in the automotive domain.

    The initial parts of the thesis give an overview of systems, subsystems and network technologies found and used in the automotive domain. Then, the share-driven scheduling framework is presented, analytically investigated and proven, as well as evaluated in a simulation study. Finally it is shown how the framework is to be configured and used in the context of subsystem integration. The results show that the framework allows for flexible and efficient scheduling of messages with real-time constraints, facilitating integration of subsystems from a network point of view.

  • 311.
    Nolte, Thomas
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Hansson, Hans
    Mälardalen University, Department of Computer Science and Electronics.
    Lo Bello, Lucia
    University of Catania, Catania, Italy .
    Integration of networked subsystems in a resource constrained environment2006In: Proceedings of 11th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA'06), Prague, Czech Republic, 2006, p. 905-912Conference paper (Refereed)
    Abstract [en]

    When developing embedded systems, there is currently a trend to move from a traditional federated approach, where computer systems are developed for their own dedicated hardware architecture, to an integrated approach, where computer systems are encapsulated as subsystems and later integrated on a shared hardware architecture. The task of integrating subsystems is complex, and in resource constrained systems efficient techniques and methods are required. In this paper the issue of subsystem integration is thoroughly discussed, and it is shown how to use Server-CAN, a network scheduler for the Controller Area Network, in the context of subsystem integration. As the network is a resource shared by all subsystems in adistributed architecture, its role in the integration process is particularly important. Here, the usage of an efficient and flexible network scheduler is essential.

  • 312.
    Nolte, Thomas
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Lo Bello, Lucia
    Mälardalen University, Department of Computer Science and Electronics.
    Hansson, Hans
    Mälardalen University, Department of Computer Science and Electronics.
    Facilitating subsystem integration by decoupling priority and identifier in CAN messages2006In: Proceedings of the 5th International Workshop on Real-Time Networks (RTN'06) in conjunction with the 18th Euromicro International Conference on Real-Time Systems (ECRTS'06), Dresden, Germany, 2006Conference paper (Refereed)
  • 313.
    Nolte, Thomas
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Nolin, M.
    Hansson, H. A.
    Mälardalen University, Department of Computer Science and Electronics.
    Real-time server-based communication with CAN2005In: IEEE transactions on industrial electronics (1982. Print), ISSN 0278-0046, E-ISSN 1557-9948, Vol. 1, no 3, p. 192-200Article in journal (Refereed)
    Abstract [en]

    This paper investigates the concept of share-driven scheduling of networks using servers with real-time properties. Share-driven scheduling provides fairness and bandwidth isolation between predictable as well as unpredictable streams of messages on the network. The need for this kind of scheduled real-time communication network is high in applications that have requirements on flexibility, both during development for assigning communication bandwidth to different applications, and during run-time to facilitate dynamic addition and removal of system components. We illustrate the share-driven scheduling concept by applying it to the popular controller area network (CAN). We propose a scheduling mechanism that we call simple server-scheduled CAN (S-3-CAN), for which we also present an associated timing analysis. Additionally, we present a variant of S'-CAN called periodic server-scheduled CAN (PS2-CAN), which for some network configurations gives lower worst-case response-times than S-3-CAN. Also for this improvement, a timing analysis is presented. Moreover, we use simulation to evaluate the timing performance of both S-3-CAN and PS2-CAN, comparing them with other scheduling mechanisms.

  • 314.
    Nolte, Thomas
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Nyström, Dag
    Mälardalen University, Department of Computer Science and Electronics.
    Introducing Substitution-Queries in Distributed Real-Time Database Management Systems2005In: IEEE International Conference on Emerging Technologies and Factory Automation, ETFA, 2005, p. 707-714Conference paper (Other academic)
    Abstract [en]

    This paper introduces query mechanisms that allow automotive control-systems (using a distributed real-time database management system(RTDBMS)) to be queried, monitored and stimulated during run-time without violating its temporal properties. The mechanisms are completely transparent to the control application since they are handled by the RTDBMS. The COMET RTDBMS is extended with ad hoc capabilities to support the introduction of subscription and substitution queries, which are used for monitoring and stimulation. These queries are intended to be used by service and calibration tools to help in the development and maintenance of modern automotive systems. Using these queries could reduce development costs, result in higher quality of the system design and consequently yield higher reliability.

  • 315.
    Nordström, Susanna
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Asplund, Lars
    Mälardalen University, Department of Computer Science and Electronics.
    Configurable Hardware/Software Support for Single Processor Real-Time Kernels2007In: 2007 INTERNATIONAL SYMPOSIUM ON SYSTEM-ON-CHIP PROCEEDINGS, 2007, p. 66-69Conference paper (Refereed)
    Abstract [en]

    Today's software based real-time operating systems (RTOS) have the ability to be configured in order to decrease memory footprint, important when the RTOS is used in resource restricted embedded environments. When the kernel is implemented in hardware, not only memory footprint is motivation for configuration for minimization, the number of logic cells occupied in the FPGA has to be considered as well.

    We have modified existing hardware support, the real-time unit (RTU) for increased configurability. The modified RTU was compared regarding configuration and footprint with a corresponding system based on the commercial software RTOS MicroC/OS-II. Four different configuration settings were compared and the results show that the RTU memory footprint was 24% to 38% of the size of the MicroC/OS-II footprint. In FPGA area, the smallest configuration of the RTU occupied only 50% of the logic cells used by the largest configuration. Configurability of an RTOS with hardware support, like the RTU, decreases project cost since it is more likely to be able to use a low cost FPGA when adjusting implemented functionality to only include what is required by the application.

  • 316.
    Norström, Christer
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Hansson, H. A.
    Mälardalen University, Department of Computer Science and Electronics.
    Special section on factory communication systems2005In: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 1, no 3, p. 149-150Article in journal (Other academic)
  • 317.
    Nyström, Dag
    Mälardalen University, Department of Computer Science and Electronics.
    Data Management in Vehicle Control-Systems2005Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    As the complexity of vehicle control-systems increases, the amount of information that these systems are intended to handle also increases. This thesis provides concepts relating to real-time database management systems to be used in such control-systems. By integrating a real-time database management system into a vehicle control-system, data management on a higher level of abstraction can be achieved. Current database management concepts are not sufficient for use in vehicles, and new concepts are necessary. A case-study at Volvo Construction Equipment Components AB in Eskilstuna, Sweden presented in this thesis, together with a survey of existing database platforms confirms this. The thesis specifically addresses data access issues by introducing; (i) a data access method, denoted database pointers, which enables data in a real-time database management system to be accessed efficiently. Database pointers, which resemble regular pointers variables, permit individual data elements in the database to be directly pointed out, without risking a violation of the database integrity. (ii) two concurrency-control algorithms, denoted 2V-DBP and 2V-DBP-SNAP which enable critical (hard real-time) and non-critical (soft real-time) data accesses to co-exist, without blocking of the hard real-time data accesses or risking unnecessary abortions of soft real-time data accesses. The thesis shows that 2V-DBP significantly outperforms a standard real-time concurrency control algorithm both with respect to lower response-times and minimized abortions. (iii) two concepts, denoted substitution and subscription queries that enable service- and diagnostics-tools to stimulate and monitor a control-system during run-time. The concepts presented in this thesis form a basis on which a data management concept suitable for embedded real-time systems, such as vehicle control-systems, can be built.

  • 318.
    Nyström, Dag
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Nolin, Mikael
    Norström, Christer
    Snapshots in Real-Time Database using Database Pointer Transactions2005In: Proceedings - 11th IEEE International Conference on Embedded and Real-Time Computing Systems and Applications, 2005, p. 343-349Conference paper (Other academic)
    Abstract [en]

    We present 2V-DBP-SNAP an algorithm that allows hard real-time tasks in an embedded real-time control system to read a snapshot of a number of data elements in a real-time database. Furthermore, 2V-DBP-SNAP allows these data elements to be shared with soft real-time tasks, which access them using a database query language, and with other hard real-time tasks that use database pointers. 2V-DBP-SNAP allows temporal behavior and memory consumption to be accurately predicted. Introducing snapshot transactions is beneficial for embedded control-systems, such as for engine control in an automotive system, since a snapshot of the state of the environment can be collected, e.g., the state of all cylinders in the engine. 2V-DBP-SNAP is lightweight and predictable, both with respect to computational and memory overhead, and is therefore highly suited for resource constrained systems.

  • 319.
    Nyström, Dag
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Tesanovic, Aleksandra
    Nolin, Mikael
    Norström, Christer
    Hansson, Jörgen
    COMET: A Component-Based Real-Time Database for Automotive Systems2004In: Proceedings of the IEEE Workshop on Software Engineering for Automotive Systems, 2004Conference paper (Other academic)
  • 320.
    Nyström, Dag
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Tesanovic, Aleksandra
    Linköping University, Dept. of Computer Science, Linköping, Sweden .
    Norström, Christer
    Mälardalen University, Department of Computer Science and Electronics.
    Hansson, Jörgen
    Linköping University, Dept. of Computer Science, Linköping, Sweden .
    Bånkestad, Nils-Erik
    Volvo Construction, Eskilstuna, Sweden.
    Data Management Issues in Vehicle Control Systems: a Case Study2002In: Proceedings - Euromicro Conference on Real-Time Systems 2002, 2002, p. 249-256Conference paper (Other academic)
    Abstract [en]

    We present a case study of a class of embedded hard real-time control applications in the vehicular industry which, in addition to meeting transaction and task deadlines, emphasize data validity requirements. We elaborate on how a database could be integrated into the studied application and how the database management system (DBMS) could be designed to suit this particular class of systems.

  • 321.
    Nyström, Dag
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Tesanovic, Aleksandra
    Noström, Christer
    Hansson, Jörgen
    Database Pointers: Efficient and Predictable Data Access in Real-Time Control-SystemsOther (Refereed)
  • 322.
    Olsson, Erik
    Mälardalen University, Department of Computer Science and Electronics.
    Diagnosis of Machines within Industry using Sensor Signals and Case-Based Reasoning2005Licentiate thesis, comprehensive summary (Other scientific)
  • 323.
    Olsson, Erik
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Ahmed, Mobyen Uddin
    Mälardalen University, Department of Computer Science and Electronics.
    Funk, Peter
    Mälardalen University, Department of Computer Science and Electronics.
    Xiong, Ning
    Mälardalen University, Department of Computer Science and Electronics.
    A CASE STUDY OF COMMUNICATION IN A DISTRIBUTED MULTI-AGENT SYSTEM IN A FACTORY PRODUCTION ENVIRONMENT2007Conference paper (Refereed)
    Abstract [en]

    A Distributed Multi-Agent System representing the behaviour of a machine maintenance procedure in a factory production environment is modelled using the BRIC language. The model provides an overview and simplification of the communication in the maintenance procedure. The model involves two distributed factory environments, each equipped with a Maintenance Agent and an Experience Sharing Agent. Maintenance agents can be seen as experts in interpreting local sensor data from the machine being observed. They have some basic domain knowledge about when to bring the findings to the attention of an agent, human or system. An agent is also autonomous and may have the trust to shut down a process. The maintenance agent will ask other agents or humans for assistance if bringing the macine ito working order is beyond the agent's ability. Necessary information about what maintenance actions to perform is provided by an Experience Sharing Agent which has the ability to identify past experience relevant for the current situation and thus beeing able to help the human to make a better and more informed decision avoiding previously, sometimes very costly mistakes.

  • 324.
    Olsson, Erik
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Funk, Peter
    Mälardalen University, Department of Computer Science and Electronics.
    Bengtsson, Marcus
    Mälardalen University, Department of Innovation, Design and Product Development.
    Fault Diagnosis of Industrial Robots using Acoustic Signals and Case-Based Reasoning2004In: Case-Based Reasoning. ECCBR 2004. Lecture Notes in Computer Science, vol 3155, 2004, p. 686-701Conference paper (Refereed)
    Abstract [en]

    In industrial manufacturing rigorous testing is used to ensure that the delivered products meet their specifications. Mechanical maladjustment or faults often show their presence as deviations compared to a normal sound pro-file. This is the case in robot assembly, the selected application domain for the system. Manual diagnosis based on sound requires extensive experience, and the experience is often acquired through costly mistakes and reduced production efficiency or quality loss caused by missed faults. The acquired experience is also difficult to preserve and transfer, and often lost if personnel leave the task of testing and fault diagnosis. We propose a Case-Based Reasoning approach to collect and preserve experience. The solution enables fast experience transfer and leads to less experienced personnel required to make more reliable and informed testing. Sounds from normal and faulty equipment are recorded and stored in a case library together with a diagnosis. Addition of new validated sound profiles continuously improves the system’s performance. The system can preserve and transfer experience between technicians, reducing overall fault identification time and increases quality by reduced number of missed faults. The original sound recordings are stored in form of the extracted features to-gether with other experience, e.g. instructions, additional tests, advice, user feedback etc.

  • 325.
    Olsson, Erik
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Funk, Peter
    Mälardalen University, Department of Computer Science and Electronics.
    Xiong, Ning
    Mälardalen University, Department of Computer Science and Electronics.
    Fault Diagnosis in Industry Using Sensor Readings and Case-Based Reasoning2004In: Journal of Intelligent & Fuzzy Systems, ISSN 1064-1246, Vol. 15, no 1, p. 41-46Article in journal (Refereed)
    Abstract [en]

    Fault diagnosis of industrial equipments becomes increasingly important for improving the quality of manufacturing and reducing the cost for product testing. Developing a fast and reliable diagnosis system presents a challenge issue in many complex industrial scenarios. The major difficulties therein arise from contaminated sensor readings caused by heavy background noise as well as the unavailability of experienced technicians for support. In this paper we propose a novel method for diagnosis of faults by means of case-based reasoning and signal processing. The received sensor signals are processed by wavelet analysis to filter out noise and at the same time to extract a group of related features that constitutes a reduced representation of the original signal. The derived feature vector is then forwarded to a classification component that uses case-based reasoning to recommend a fault class for the probe case. This recommendation is based on previously classified cases in a case library. Case-based diagnosis has attractive properties in that it enables reuse of past experiences whereas imposes no demand on the size of the case base. The proposed approach has been applied to fault diagnosis of industrial robots at ABB Robotics and the results of experiments are very promising.

  • 326.
    Olsson, Erik
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Hedelind, Mikael
    Mälardalen University, Department of Innovation, Design and Product Development.
    Ahmed, Mobyen Uddin
    Mälardalen University, Department of Computer Science and Electronics.
    Funk, Peter
    Mälardalen University, Department of Computer Science and Electronics.
    EXPERIENCE REUSE BETWEEN MOBILE PRODUCTION MODULES - AN ENABLER FOR THE FACTORY-IN-A-BOX CONCEPT2007Conference paper (Refereed)
    Abstract [en]

    Today's increased demand for flexible and fast reconfiguration of production systems is seen as one of the key factors for survival by many branches, especially small and medium sized enterprises. To enable adaptable and flexible production, we propose an integrated experience reuse system assisting in setup, operation, maintenance and repair. We present three subsystems that facilitate experience reuse between different engineers and operators working with standardised production modules. It is composed of three separate software components enabling: a) easy programming and control of robot cells, b) monitoring and condition based maintenance, c) distributed experience reuse. The results presented in this paper have been developed within the Factory-in-a-Box project, the ExAct project and the Eken project.

  • 327.
    Olsson, Erik
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Stolyarchuk, Rostyslav
    State Scientific and Research Institute of Information Infrastructure, Lviv, Ukraine .
    Dynamic Modeling and Sound (Noise) Diagnostics of Robot Gearboxes for Fault Assessments2005In: Proceedings of SIMS 2005 - Scandinavian Conference on Simulation and Modeling, 2005Conference paper (Refereed)
    Abstract [en]

    Some gear faults in industrial robots can during operation be recognized as abnormal noise peaks coming from the gearbox. A library of such recordings has been assembled in order to automate fault diagnosis of the robots. A computer records sound from the gearbox and compare the new recordings with recordings stored in the library. The result of the comparison is a diagnosis of the condition of the robot. This paper proposes an extension of the sound library by incorporating model based reasoning. A dynamic model of the gearbox in the drive system has been constructed and gear vibrations on the force level are extracted from the model. These vibrations are projected onto the sound recordings with a statistical vibration diagnostic parameter known as the Crest Factor CF.

  • 328.
    Ouimet, Martin
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Lundqvist, Kristina
    Mälardalen University, Department of Computer Science and Electronics.
    A Mapping between the Timed Abstract State Machine Language and UPPAAL's Timed Automata2007Report (Other academic)
  • 329.
    Ouimet, Martin
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Lundqvist, Kristina
    Mälardalen University, Department of Computer Science and Electronics.
    Formal Software Verification: Model Checking and Theorem Proving2007Report (Other academic)
  • 330.
    Ouimet, Martin
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Lundqvist, Kristina
    Mälardalen University, Department of Computer Science and Electronics.
    The Production Cell System2007Report (Other academic)
  • 331.
    Ouimet, Martin
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Lundqvist, Kristina
    Mälardalen University, Department of Computer Science and Electronics.
    The Timed Abstract State Machine Language: An Executable Specification Language for Reactive Real-Time Systems2006In: 27th IEEE International Real-Time Systems Symposium (RTSS '06) - Work in Progress Session, Rio De Janeiro, Brazil, 2006Conference paper (Refereed)
  • 332.
    Ouimet, Martin
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Lundqvist, Kristina
    Mälardalen University, Department of Computer Science and Electronics.
    Verifying Execution Time using the TASM Toolset and UPPAAL2007Report (Other academic)
  • 333.
    Ouimet, Martin
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Lundqvist, Kristina
    Mälardalen University, Department of Computer Science and Electronics.
    Sjödin, Mikael
    Mälardalen University, Department of Computer Science and Electronics.
    The Timed Abstract State Machine Language: An Executable Specification Language for Reactive Real-Time Systems2007In: Proceedings of the 15th International Conference on Real-Time and Network Systems (RTNS '07), 2007Conference paper (Refereed)
  • 334.
    Ouimet, Martin
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Quenot, Mathieu
    Mälardalen University, Department of Computer Science and Electronics.
    Lundqvist, Kristina
    Mälardalen University, Department of Computer Science and Electronics.
    Mathematical Programming for Automated Verification of System Specifications and Automated Test Case Generation2007Report (Other academic)
  • 335.
    Ozcan, Oguzhan
    et al.
    Yildiz Technical University, Istanbul, Turkey.
    Thomassen, Aukje
    Utrecht School of the Arts, The Netherlands.
    Baumann, Konrad
    FH Joanneum, Graz.
    Holmgren, Mette
    Mälardalen University, Department of Computer Science and Electronics.
    Lindell, Rikard
    Mälardalen University, Department of Computer Science and Electronics.
    The Role of Traditional Shadow Play on Creativity in Interaction Design2007Conference paper (Refereed)
    Abstract [en]

    Interaction design within the area of Human Computer Interaction has been around at least the last half of the twentieth century. However, some argue that interaction design has been a part of the human experience much longer. Throughout history, different cultures did have different techniques for the art of interactive performance, in parallel with the developing technology. These techniques were quite different from today’s computer interfaces and our

    way of looking at it. It is believed that, today, if we can understand the philosophy behind these techniques of different cultures from different parts of the world, we can make an important improvement in producing designs that go beyond the limitations of two-dimensional interfaces for interactive media design. From this reality, we face the challenge of reinterpreting the early performance techniques by using the advantages of today’s technology. This challenge can be developed in such a way that it may be possible to add new dimensions to our concepts of interactive media design by examining the techniques of the art of show of past cultures. There are many examples in history to answer the articulated challenges. One of them is the technique of “shadow play” which is quite parallel to interactive media. In this paper, by looking into the typology of the traditional “shadow play”, the challenge of developing these new concepts for interactive media is examined by 10 projects which belong to 40 European Design Students who joint European Interaction Design Summer School funded by European Union ERASMUS Intensive Program. (Please see projects at http://www.khas.edu.tr/idss and please see detailed philosophy at http://idcourse.hku.nl/)

  • 336.
    Pavlova, Irena
    et al.
    Sofia University, Sofia, Bulgaria.
    Åkerholm, Mikael
    Mälardalen University, Department of Computer Science and Electronics.
    Fredriksson, Johan
    Mälardalen University, Department of Computer Science and Electronics.
    Application of Built-In-Testing in Component-Based Embedded Systems2006In: Proceedings of the ISSTA 2006 Workshop on Role of Software Architecture for Testing and Analysis, ROSATEA '06, 2006, p. 51-52Conference paper (Refereed)
    Abstract [en]

    This work-in-progress paper discusses challenges with application of Built-In Testing (BIT) in component-based embedded-systems. Testing constitutes a large part of the time and budget in development of embedded software systems. Such systems are often mission-critical, making testing highly important, and at the same time testing em-bedded systems is challenging because of their limited observability. We investigate the possible application of BIT in components for embedded systems, as a technique to advance the technology and knowledge for analysis and verification of functional correctness, real-time behavior, safety, and reliability of these systems.

  • 337.
    Persson Dahlqvist, Annita
    Mälardalen University, Department of Computer Science and Electronics.
    Product data management and software configuration management integration 2005Licentiate thesis, comprehensive summary (Other scientific)
  • 338.
    Pettersson, Anders
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Sundmark, Daniel
    Mälardalen University, Department of Computer Science and Electronics.
    Thane, Henrik
    Mälardalen University, Department of Computer Science and Electronics.
    Nyström, Dag
    Mälardalen University, Department of Computer Science and Electronics.
    Shared Data Analysis for Multi-Tasking Real-Time System Testing2007In: 2007 Symposium on Industrial Embedded Systems Proceeedings, SIES'2007, 2007, p. 110-117Conference paper (Refereed)
    Abstract [en]

    Memory corruption due to program faults is one of the most common failures in computer software. For software running in a sequential manner and for multi-tasking software with synchronized data accesses, it has been shown that program faults causing memory corruption can be detected by analyzing the relations between defines and uses of variables (DU coverage-based testing). However, using such methods in testing for memory corruption where globally shared data is accessed through asynchronous events will not be sufficient since they lack the possibility to analyse the cases where preemption of tasks may lead to interleaving failures. In this paper, we propose the use of a system level shared variable DU analysis of multi-tasking realtime software. By analyzing the temporal attributes of each access to globally shared data, our method handles asynchronous data accesses. When used in system-level testing, the result from the analysis can discover failures such as ordering, synchronization and interleaving failures. The result can also serve a as measure for coverage and complexity in data dependency at system level.

  • 339.
    Proenza, Julian
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Miro-Julia, José
    Mälardalen University, Department of Computer Science and Electronics.
    Hansson, Hans
    Mälardalen University, Department of Computer Science and Electronics.
    Redundancy Management in a Low-Cost Distributed Hardware and Firmware Support for Software-Fault Tolerance2007Report (Other academic)
    Abstract [en]

    Software is a major source of reliability degradation in dependable systems.

    One of the classical remedies is to provide software fault-tolerance by using NVersion

    Programming (NVP). However, due to requirements on special hardware

    and the need for changes and additions at all levels of the system, NVP solutions

    are costly, and have only been used in special cases.

    In a previous work, a low-cost architecture for NVP execution was developed.

    The key features of this architecture are the use of off-the-shelf components

    and that the fault-tolerance functionality, including voting, error detection,

    fault-masking, consistency management, and recovery, is moved into a separate

    redundancy management circuitry (one for each redundant computing node).

    In this article we present an improved design of that architecture, specifically

    resolving some potential inconsistencies that were not treated in detail in the original

    design. In particular, we present novel techniques for enforcing replica determinism

    and a method for reintegration of the redundancy management circuitry

    after a transient failure.

    Our improved architecture is based on using the Controller Area Network

    (CAN). This has several benefits, including low-cost, and that the CAN data consistency

    allows us to simplify the mechanisms for replica determinism and reintegration.

    Although initially developed for NVP, our redundancy management circuitry

    also supports other software replication techniques, such as active replication.

  • 340.
    Punnekkat, Sasikumar
    Mälardalen University, Department of Computer Science and Electronics.
    Schedulability Analysis for Fault Tolerant Real-time Systems1997Doctoral thesis, monograph (Other scientific)
  • 341.
    Rattfält, Linda
    et al.
    Linköping University, Linköping, Sweden.
    Ahlström, Christer
    Linköping University, Linköping, Sweden.
    Berglin, Lena
    University College of Borås, Borås, Sweden .
    Lindén, Maria
    Mälardalen University, Department of Computer Science and Electronics.
    Hult, Peter
    Linköping University, Linköping, Sweden.
    Ask, Per
    Linköping University, Linköping, Sweden.
    Wiklund, Urban
    Umeå University Hospital, Umeå, Sweden.
    A canonical correlation approach to heart beat detection in textile ECG measurements2006In: IET Conference Publications, Issue 520, 2006Conference paper (Refereed)
    Abstract [en]

    Research in textile sensors has lead to new ways to measure electrocardiograms (ECG). However, additional disturbances from, for example, muscular noise and high skin-electrode impedances often result in poor signal quality. The paper contains a simple application of canonical correlation analysis (CCA) on multi channel ECG signals recorded with textile electrodes. Using CCA to solve the blind source separation (BSS) problem, we intend to separate the ECG signal from the various noise sources. The method (CCABSS) was compared to simple averaging of the ECG channels and to the independent component analysis method (ICA). A heart beat detector was used to evaluate the signal quality. Results show that the signal was completely lost while simulating various noise in 33%, 17% and 7% of the cases for averaging, ICA and CCA, respectively.

  • 342.
    Rattfält, Linda
    et al.
    Linköping University, Linköping, Sweden.
    Lindén, Maria
    Mälardalen University, Department of Computer Science and Electronics.
    Hult, Peter
    Linköping University, Linköping, Sweden.
    Berglin, Lena
    University College of Borås, Borås, Sweden.
    Ask, Per
    Linköping University, Linköping, Sweden.
    Electrical characteristics of conductive yarns and textile electrodes for medical applications2007In: Medical and Biological Engineering and Computing, ISSN 0140-0118, Vol. 45, no 12, p. 1251-1257Article in journal (Refereed)
    Abstract [en]

    Clothing with conductive textiles for health care applications has in the last decade been of an upcoming research interest. An advantage with the technique is its suitability in distributed and home health care. The present study investigates the electrical properties of conductive yarns and textile electrodes in contact with human skin, thus representing a real ECG-registration situation. The yarn measurements showed a pure resistive characteristic proportional to the length. The electrodes made of pure stainless steel (electrode A) and 20% stainless steel/80% polyester (electrode B) showed acceptable stability of electrode potentials, the stability of A was better than that of B. The electrode made of silver plated copper (electrode C) was less stable. The electrode impedance was lower for electrodes A and B than that for electrode C. From an electrical properties point of view we recommend to use electrodes of type A to be used in intelligent textile medical applications.

  • 343.
    Rizvanovic, Larisa
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Fohler, Gerhard
    Mälardalen University, Department of Computer Science and Electronics.
    Real-time Architecture for Networked Multimedia Streaming systems2006Conference paper (Refereed)
    Abstract [en]

    The work presented here has started as part of a FABRIC EU IST

    project. The aim of the FABRIC project was to develop an

    architecture in which several interoperability standards and

    technologies in the home networking context can be integrated. In

    addition, the FABRIC aimed to handle the complete network to satisfy

    End-to-End Quality of service (QoS) requirements. In this paper we

    propose an adaptive QoS framework for efficient resource management,

    called the Matrix approach. The Matrix is a concept to abstract from

    having detailed technical data at the middleware interface. In stead

    of having technical data referring to QoS parameters like:

    bandwidth, latency and delay we only have discrete portions that

    refer to levels of quality. The underlying middleware must interpret

    these values and map them on technical relevant QoS parameters.

  • 344.
    Rizvanovic, Larisa
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Fohler, Gerhard
    Mälardalen University, Department of Computer Science and Electronics.
    The Matrix - A framework for real-time resource management for video streaming in networks of hetero2007Report (Other academic)
    Abstract [en]

    Efficient transport of streams with acceptable playout quality in in heterogenous, dynamic environment (e.g. home networks) requires management of both networks and CPUs. This paper presents a framework for applying real-time resource management methods for decoupled video streaming of heterogenous devices. It is based on a global abstraction of device states, which reduces system state information and decreases overheads for its determination and dissemination. It provides access to the entire system state in acceptable fresh way, enabling system wide optimized decisions to be taken. This work has started as part of a FABRIC EU IST project. The aim of the FABRIC project was to develop an architecture in which several interoperability standards and technologies in the home networking context can be integrated. In addition, the FABRIC aimed to handle the complete network to satisfy End-to-End Quality of service (QoS) requirements. In this paper we propose an adaptive QoS framework for efficient resource management, called the Matrix approach. The Matrix is a concept to abstract from having detailed technical data at the middleware interface. In stead of having technical data referring to QoS parameters like: bandwidth, latency and delay we only have discrete portions that refer to levels of quality. The underlying middleware must interpret these values and map them on technical relevant QoS parameters. 

  • 345.
    Rizvanovic, Larisa
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Fohler, Gerhard
    Mälardalen University, Department of Computer Science and Electronics.
    The MATRIX - A Framework for Real-time Resource Management for Video Streaming in Networks of Heterogenous Devices2007Conference paper (Refereed)
    Abstract [en]

    Efficient transport of streams with acceptable playout quality in heterogeneous, dynamic environment (e.g. home networks) requires management of both networks and CPUs. This paper presents a framework for applying real-time resource management methods for decoupled video streaming in networks of heterogeneous devices. It is based on a global abstraction of device states, which reduces system state information and decreases overheads for its determination and dissemination. It provides access to the entire system state in acceptably fresh way, enabling system wide optimized decisions to be taken.

  • 346.
    Rizvanovic, Larisa
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Isovic, Damir
    Mälardalen University, Department of Computer Science and Electronics.
    Fohler, Gerhard
    Department of Electrical and Computer Engineering, University of Kaiserslautern, Germany.
    Integrated Global and Local Quality-of-Service Adaptation in Distributed, Heterogeneous Systems2007In: Embedded and Ubiquitous Computing: International Conference, EUC 2007, Taipei, Taiwan, December 17-20, 2007. Proceedings, Springer, 2007, p. 219-233Chapter in book (Refereed)
    Abstract [en]

    In this paper we have developed a method for an efficient Quality-of-Service provision and adaptation in dynamic, heterogeneous systems, based on our Matrix framework for resource management. It integrates local QoS mechanisms of the involved devices that deal mostly with short-term resource fluctuations, with a global adaptation mechanism that handles structural and long-term load variations on the system level. We have implemented the proposed approach and demonstrated its effectiveness in the context of video streaming.

  • 347.
    Rodriguez-Navas, Guillermo
    et al.
    Universitat de les Illes Balears, Spain.
    Hansson, Hans
    Mälardalen University, Department of Computer Science and Electronics.
    An UPPAAL Model for Formal Verification of Master/Slave Clock2006In: Factory Communication Systems, 2006 IEEE International Workshop on, 2006, p. 3-12Conference paper (Refereed)
    Abstract [en]

    Many distributed applications require a clock synchronization service. We have previously proposed a clock synchronization service for the Controller Area Network (CAN), which we have claimed to provide highly synchronized clocks even in the occurrence of faults in the system. In this paper we substantiate this claim by providing a formal model and verification of our fault tolerant clock synchronization mechanism. We base our modeling and verification on timed automata theory as implemented by the model checking tool UPPAAL. In the modeling we introduce a novel technique for modeling drifting clocks. The verification shows that a precision in the order of 2 μs is guaranteed despite node’s faults as well as consistent channel faults. It also shows that inconsistent channel faults may significantly worsen the achievable precision, but that this effect can be reduced by choosing a suitable resynchronization period.

  • 348.
    Sandberg, Christer
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Ermedahl, Andreas
    Mälardalen University, Department of Computer Science and Electronics.
    Gustafsson, Jan
    Mälardalen University, Department of Computer Science and Electronics.
    Lisper, Björn
    Mälardalen University, Department of Computer Science and Electronics.
    Faster WCET Flow Analysis by Program Slicing2006In: ACM SIGPLAN Notices, Volume 41, Issue 7, July 2006, 2006, Vol. 41, p. 103-112Conference paper (Refereed)
    Abstract [en]

    Static Worst-Case Execution Time (WCET) analysis is a technique to derive upper bounds for the execution times of programs. Such bounds are crucial when designing and verifying real-time systems. WCET analysis needs a program flow analysis to derive constraints on the possible execution paths of the analysed program, like iteration bounds for loops and dependences between conditionals.Current WCET analysis tools typically obtain flow information through manual annotations. Better support for automatic flow analysis would eliminate much of the need for this laborious work. However, to automatically derive high-quality flow information is hard, and solution techniques with large time and space complexity are often required.In this paper we describe how to use program slicing to reduce the computational need of flow analysis methods. The slicing identifes statements and variables which are guaranteed not to influence the program flow. When these are removed, the calculation time of our different flow analyses decreases, in some cases considerably.We also show how program slicing can be used to identify the input variables and globals that control the outcome of a particular loop or conditional. This should be valuable aid when performing WCET analysis and systematic testing of large and complex real-time programs.

  • 349.
    Sandell, Daniel
    et al.
    Mälardalen University, Department of Computer Science and Electronics.
    Ermedahl, Andreas
    Mälardalen University, Department of Computer Science and Electronics.
    Gustafsson, Jan
    Mälardalen University, Department of Computer Science and Electronics.
    Lisper, Björn
    Mälardalen University, Department of Computer Science and Electronics.
    Static Timing Analysis of Real-Time Operating System Code2006In: Leveraging Applications of Formal Methods: First International Symposium, ISoLA 2004, Paphos, Cyprus, October 30 - November2, 2004, Revised Selected Papers, Springer, 2006, p. 146-160Chapter in book (Refereed)
    Abstract [en]

    Methods for Worst-Case Execution Time (WCET) analysis have been known for some time, and recently commercial tools have emerged. However, the technique has so far not been much used to analyse real production codes. Here, we present a case study where static WCET analysis was used to find upper time bounds for time-critical regions in a commercial real-time operating system. The purpose was not primarily to test the accuracy of the estimates, but rather to investigate the practical difficulties that arise when applying the current WCET analysis methods to this particular kind of code. In particular, we were interested in how labor-intense the analysis becomes, measured by the number of annotations to explicitly constrain the program flow which is necessary to perform the analysis. We also make some qualitative observations regarding what a WCET analysis method would need in order to perform a both convenient and tight analysis of typical operating systems code. In a second set of experiments, we analyzed some standard WCET benchmark codes compiled with different levels of optimization. The purpose of this study was to see how the different compiler optimizations affected the precision of the analysis, and again whether it affected the level of user intervention necessary to obtain an accurate WCET estimate.

  • 350.
    Sandström, Kristian
    Mälardalen University, Department of Computer Science and Electronics.
    Enforcing Temporal Constraints in Embedded Control Systems2002Doctoral thesis, monograph (Other scientific)
    Abstract [en]

    Computer control systems are embedded in a large and growing group of products, ranging from consumer entertainment products to large airliners. Products such as automotive vehicles, aircraft, and industrial robots are equipped with advanced computer control systems and have high requirements of reliable and safe operation. A common property of these systems is that the computer systems are becoming increasingly more complex due to the inclusion of more functionality. At the same time, the product cycles are becoming shorter leading to requirements of shorter time to market. To meet this challenging task, the development of computer control systems must be a well-defined and controlled engineering process. One important part in reaching this goal is to find methods for dealing with the complexity of computer systems. A computer control system is typically realized by a set of concurrent activities with inter-dependencies that have to meet a set of pre defined temporal constraints. Because of this, it is difficult to know in advance if the implementation of a design will meet its temporal constraints. Furthermore, it is hard to foresee the consequence of introducing alterations or additional functionality in a system. For a method to be useful it also has to capture all the relevant aspects of the application domain, and in the domain of embedded control systems this includes the ability to express and enforce the temporal constraints of control activities. Moreover, the computer system is a heterogeneous system with many responsibilities. Hence, methods for embedded control systems should support not only control activities but also activities related to e.g., human-machine interaction and communication. The work presented in this thesis contributes with methods for enforcing temporal constraints in embedded control systems. The results include an industrial case study pointing out limitations in classic real-time models and giving indications of engineering needs. Moreover, a method is presented for pre-run-time scheduling of periodic control activities under the interference of sporadic interrupts. Furthermore, a method is presented for enforcement of complex temporal constraints using standard priority based real-time operating systems. Finally, the work includes a method for management of communication resources in distributed systems.

45678 301 - 350 of 388
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