<p>This thesis describes a further development of a building block for programmable devices in embedded systems handling real-time functionality.</p><p>Embedded systems are included in a variety of products within different technical areas such as industrial automation, consumer electronics, automotive industry, and communication-, and multimedia systems. Products ranging from trains and airplanes to microwave ovens and washing machines are controlled by embedded systems.</p><p>Programmable devices constitute a part of these embedded systems. Today, a programmable device can include a complete system containing building blocks connected with each other via programs written using a hardware description language. The programmable devices can be programmed and changed over and over again and this flexibility makes it possible to explore how these building blocks can best be designed in relation to system requirements, before final implementation.</p><p>This thesis describes a further development of a building block for programmable devices implemented in a non-traditional way, i.e., the implementation is written using both hardware description language and traditional software languages. This new building block handles real-time functionality in a non-traditional way that enables certain benefits, such as increased performance, predictability and less memory consumption. Using a non-traditional implementation also has its drawbacks, and e.g., extensions and adjustments can be hard to handle since modifications are required in both hardware and software programming languages.</p><p>The new building block was investigated in order to see how it could be facilitated when used for real-time functionality. The configurability of the block was extended which enables further customization of the building block. This leads to the possibility to use the block within a wider spectrumof applications. It is also possible to reduce the size and cost of the final product since resource usage can be optimized.</p><p>Furthermore, a mathematicalmodel estimating resource usage for real-time functionality has been developed. The model enables distinctive trade-offs comparisons, and guidance for system designers, when considering what type of real-time operating system to use in a certain design.</p>

In this thesis, we study temperature-constrained multiprocessor real-time systems, where real-time guarantees must be met without exceeding safe temperature levels within the processors. We focus on Pfair scheduling algorithms, especially ERfair scheduling scheme (a work-conserving extension to Pfair scheduling) as our main multiprocessor real-time scheduling methodology. Then, we study the benefits of simple reactive speed scaling as described in the real-time multiprocessor systems. In this thesis, in support of the temperature-awareness, we extend the applicability of the reactive speed scaling to global scheduling schemes for multiprocessors. We propose temperature-aware scheduling and processor selection schemes motivated by existing (thermally non-optimal) ERfair scheduling in order to reduce thermal stress and therefore increase the processor utilization. Then, we show that the proposed algorithm and reactive scheme can enhance the processor utilization compared with any constant speed scheme on real-time multiprocessor systems. Additionally, we show how the maximum schedulable utilization (MSU) for partitioning heuristics can be determined on the temperature-constrained multiprocessor real-time systems.

Presently information systems are increasingly penetrating to our daily life. Recently it is relevant to integrate the newest technologies. In that way traditional system becomes “smart” who are more economical, optimal, and self-sufficient. The biggest problem is to make a model of “smart” system. There were analyzed modeling methods, heating and cooling control systems in this job. Mathematical model for heating and cooling controller using fuzzy logic was presented. According to analyzed problems it was made verification with Matlab during experimental phase. There was made comparison evaluation of mathematical model made with fuzzy logic and timed Petri nets.

Darbe nagrinėjamas realiojo laiko sistemų, specifikuotų agregatiniu metodu, verifikavimo uždavinys. Sprendžiant šį uždavinį, naudojama pasiekiamų būsenų grafo sudarymo metodika, leidžianti įvertinti laiko intervalus, kuriais įvyksta sistemoje apibrėžti įvykiai. Darbe nagrinėjami pasiekiamų būsenų grafo sudarymo algoritmai ir pateikta prototipinėse programose naudojama duomenų struktūra. Suformuluoti ir įrodyti teiginiai apie pasiekiamų būsenų grafo sudarymo algoritmo sudėtingumą (maksimalaus vienos būsenos galimų perėjimų skaičiaus; grafo viršūnių skaičiaus augimo priklausomybės nuo įvykių skaičiaus; maksimalaus įvykių skaičiaus elgsenoje laiko intervale; maksimalaus viršūnių skaičiaus laiko intervale.) Pateikta trijų testinių sistemų grafų automatizuoto sudarymo analizė. Parodyta, kad Simplekso optimizavimo procedūra laiko momentų palyginimui gali būti naudojama tik atskirais atvejais. / The work deals with a verification task of real time system specified by aggregate method. While solving the task, a technique for creation a reachable state graph is used. The technique permits to evaluate intervals of time when the defined system events occur. Reachable state graph creation algorithms are analysed in the work. A data structure used in prototype software is presented in the work too. Assertions about a complexity of algorithm for reachable state graph creation are formulated and proved. These assertions concern maximum number of transitions from single state, dependency of number of graph verteles growth on a number of events, maximum number of events in a behaviour during time interval, and maximum number of vertexes during time interval. Analysis of automated creation of graphs for three test systems is presented. It is shown that Simplex optimisation procedure for comparison of time intervals can be used only in certain cases.

This thesis describes a further development of a building block for programmable devices in embedded systems handling real-time functionality. Embedded systems are included in a variety of products within different technical areas such as industrial automation, consumer electronics, automotive industry, and communication-, and multimedia systems. Products ranging from trains and airplanes to microwave ovens and washing machines are controlled by embedded systems. Programmable devices constitute a part of these embedded systems. Today, a programmable device can include a complete system containing building blocks connected with each other via programs written using a hardware description language. The programmable devices can be programmed and changed over and over again and this flexibility makes it possible to explore how these building blocks can best be designed in relation to system requirements, before final implementation. This thesis describes a further development of a building block for programmable devices implemented in a non-traditional way, i.e., the implementation is written using both hardware description language and traditional software languages. This new building block handles real-time functionality in a non-traditional way that enables certain benefits, such as increased performance, predictability and less memory consumption. Using a non-traditional implementation also has its drawbacks, and e.g., extensions and adjustments can be hard to handle since modifications are required in both hardware and software programming languages. The new building block was investigated in order to see how it could be facilitated when used for real-time functionality. The configurability of the block was extended which enables further customization of the building block. This leads to the possibility to use the block within a wider spectrumof applications. It is also possible to reduce the size and cost of the final product since resource usage can be optimized. Furthermore, a mathematicalmodel estimating resource usage for real-time functionality has been developed. The model enables distinctive trade-offs comparisons, and guidance for system designers, when considering what type of real-time operating system to use in a certain design.

GlobalEye is an aircraft by Saab that provides surveillance of air, sea, and land. In order to train on the system present in this aircraft a Mission Training System, MTS, is used. The MTS consists of the Command and Control, C2, system that is present in the aircraft as well as a scenario simulator. This master thesis is focused on evaluating the performance of the distributed real-time system that is the MTS in terms CPU and memory usage of its Java processes. These Java processes are divided across four servers and two types of workstations.  Two sorts of tests were conducted; workload model testing and user scenario testing. Both tests were conducted multiple times with different amount of workload. The workload was defined as a number of air and sea targets added to the scenario simulator. The data was collected by running bash scripts on each machine that saved the CPU and memory output from the Linux top command. Java VisualVM was used to examine a selection of processes further. In Java VisualVM the heap size, garbage collector pauses, and CPU time of the methods were the main focus of interest. The result from the workload model testing showed that a large majority of the processes handled an increased workload in terms of memory usage well. When it comes to the CPU usage four processes with significantly increasing CPU values were examined further in Java VisualVM. These processes were MMI processes and processes involved in data transfer. No problems were noted regarding the garbage collection and heap sizes. The longest pause, across all processes, caused by garbage collection was 29.7ms. The methods with highest amount of CPU self time were also identified for the processes. One observation was that a method related to map rendering, for the MMI processes, showed decreases in CPU time as the workload increased. The result from the user scenario testing showed that the MMI of the scenario simulator suffers delays dependant on the number of targets present in the scenario. The Java process of the MMI did increase its CPU usage significantly as the targets increased. In Java VisualVM it was observed that the garbage collector for the scenario simulator MMI process was more extensive during these tests, with the longest pause being 104ms. Lastly when it comes to the CPU self time of the methods within the MMI process, one error related method was identified.

La musique mixte se caractérise par l’association de musiciens instrumentistes et de processus électroniques pendant une performance. Ce domaine soulève des problématiques sur l’écriture de cette interaction et sur les mécanismes qui permettent d’exécuter des programmes dans un temps partagé avec les musiciens.Ce travail présente le système temps réel Antescofo et son langage dédié. Il permet de décrire des scénarios temporels où des processus sont calculés et ordonnancés en interaction avec un environnement musical. Antescofo couple un système de suivi de partition avec un système réactif temporisé.L’originalité du système réside dans la sémantique temporelle du langage adaptée aux caractéristiques critiques de l’interaction musicale. Le temps et les événements peuvent s’exprimer de façon symbolique dans une échelle en secondes ou dans des échelles relatives à des tempos.Nous présenterons les domaines de recherche apparentés à Antescofo en musique et en informatique, les caractéristiques du langage et de la partie réactive d’Antescofo qui ont été développés pendant cette thèse en particulier les stratégies synchronisations et les différents contrôles du temps et des évènements permis par le système. Nous donnerons une sémantique du langage qui formalise le fonctionnement du moteur d’exécution. À travers une série d’exemples d’applications issues de collaborations artistiques, nous illustrerons les interactions temporelles qu’il faut gérer entre une machine et un instrumentiste lors d’un concert. Le système a pu être validé à travers de nombreux concerts par différents orchestres d’envergure internationale. / Mixed music is the association in live performance of human musicians and computer mediums, interacting in real-time. Authoring the interaction between the humans and the electronic processes, as well as their real-time implementation, challenge computer science in several ways. This contribution presents the Antescofo real-time system and its domain specific language. Using this language a composer is able to describe temporal scenarios where electronic musical processes are computed and scheduled in interaction with a live musician performance. Antescofo couples artificial machine listening with a reactive and temporized system. The challenge in bringing human actions in the loop of computing is strongly related the specification and the management of multiple time frameworks and timeliness of live execution despite heterogeneous nature of time in the two mediums. Interaction scenarios are expressed at a symbolic level through the management of musical time (i.e., events like notes or beats in relative tempi) and of the physical time (with relationships like succession, delay, duration, speed between the occurrence of the events during the performance on stage). Antescofo unique features are presented through a series of examples which illustrate how to manage execution of different audio processes through time and their interactions with an external environment. The Antescofo approach has been validated through numerous uses of the system in live electronic performances in contemporary music repertoire by various international music ensembles.

This thesis is aimed to specify and implement multi-purpose framework able to deal with graphical real-time system specification. This tool allows to use arbitrary verification approach to resulting system model check. Description of basic formal specification methods based on mathematic logic is done. Some well-known hierarchical graphical specifications for real-time systems are depictured. Author proposed suitable cases for functionality examination of resulting framework.

The existence of distributed real-time systems calls for protocols for high accuracy time synchronization between devices. One such protocol, the Precision Time Protocol (PTP) reaches sub microsecond synchronization precision. PTP can be implemented both in hardware and software. This study aimed to analyze how system stress could affect the accuracy and precision of software implemented PTP between two devices. This was done using two Intel Galileo Generation 2 running Linux systems. Software was used to simulate CPU, I/O, network, and OS usage. Data was extracted from software logs and summarized in charts and then analyzed. The results showed that PTP synchronization accuracy and precision does suffer under certain types of system load, most notably under heavy I/O load. However the results might not be applicable to real-world scenario due to limitations in hardware and the synthetic stress tests do not correspond to real-world usage. Further research is required to analyze why and how different types of system load affects PTPs accuracy and precision. / Förekomsten av distribuerade realtidssystem kräver protokoll för noggrann tidssynkronisering mellan enheter. Ett sådant protokoll, Precision Time Protocol (PTP), kan uppnå en precision på under mikrosekunden under synkronisering. PTP kan implementeras i både hårdvara och mjukvara. Den här rapporten fokuserar på att analysera hur systembelastning kan påverka precision och noggrannheten hos mjukvaruimplementerad PTP mellan två enheter. Testen utfördes på två stycken Intel Galileo Generation 2 kö- randes Linux. Mjukvara användes sedan för att simulera belastning på olika system såsom CPU, I/O, nätverk och på operativsystemet. Data extraherades ifrån loggar från mjukvaran, vilken sammanfattades i grafer för att sedan analyseras. Resultaten visade att precisionen och noggrannheten hos PTP försämras under vissa typer av systembelastningar, mest märkbart under tung I/O belastning. Resultaten är dock potentiellt inte applicerbara på verklighetscenarion på grund av begränsingar i hårdvaran samt att syntetiska stresstest inte motsvarar normal belastning. Ytterligare forskning krävs för att analysera hur och varför olika typer av systembelastning påverkar PTPs precision och noggrannhet.

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Flight Safety concerns increase proportionally with increasing missile performance. These concerns are greatest in the near launch arena where a missile has the greatest potential energy. Systems such as radar, GPS tracking systems, and optics are normally of limited use in this arena for a number of reasons. A system was required that would provide useful tracking data in the first few seconds of a missile launch. This system has met that requirement providing nominal path deviation data from the launcher out to as much as 120 seconds. The tracking system described herein uses the principle of radio interferometry to derive phase difference measurements between carefully spaced antennas. These measurements are transmitted to the Operational Display Facility and converted to a usable angular deviation plot for use by Flight Safety Personnel. This paper provides an elementary radio interferometer system background and discusses this particular system setup and use. Some detail is provided on the premission simulation and setup of the system as well as the real-time display setup and output of the final data product.