@article{RaabMottokMeier, author = {Raab, Peter and Mottok, J{\"u}rgen and Meier, Hans}, title = {OSEK-RTOS f{\"u}r Jedermann (Teil 1)}, series = {Embedded Software Engineering Report}, volume = {53}, journal = {Embedded Software Engineering Report}, number = {September}, pages = {14 -- 15}, language = {de} } @article{DeubzerMottokMargulletal., author = {Deubzer, Michael and Mottok, J{\"u}rgen and Margull, Ulrich and Niemetz, Michael and Wirrer, Gerhard}, title = {Efficient Scheduling of Reliable Automotive Multi-core Systems with PD² by Weakening ERfair Task System Requirements}, series = {Automotive Safety and Security}, journal = {Automotive Safety and Security}, pages = {53 -- 67}, abstract = {Partly Proportionate fair (Partly-Pfair) scheduling, which allows task migration at runtime and assigns each task processing time with regard to its weight, makes it possible to build highly efficient embedded multi-core systems. Due to its non-work-conserving behavior, which might leave the CPU idle even when tasks are ready to execute, tasks finish only shortly before their deadlines are reached. Benefits are lower task jitter, but additional workload, e.g. through interrupts, can lead to deadline violations. In this paper we present a work-conserving extension of Partly-Pfair scheduling, called PERfair scheduling and the algorithm P-ERfair-PD2 which applies Pfair modifications used for Partly-Pfair on the concept of ERfairness and PD2 policies. With a simulation based schedulability examination we show for multiple time base (MTB) task sets that P-ERfair- PD2 has the same performance as Partly-Pfair-PD2. Additionally, we show that P-ERfair- PD2 has a much higher robustness against perturbations, and therefore it is well suited for embedded domains, especially for the Automotive domain.}, language = {en} } @article{DeubzerSchillerMottoketal., author = {Deubzer, Michael and Schiller, Frank and Mottok, J{\"u}rgen and Niemetz, Michael and Margull, Ulrich}, title = {Effizientes Multicore-Scheduling in Eingebetteten Systemen - Teil 1: Algorithmen f{\"u}r zuverl{\"a}ssige Echtzeitsysteme}, series = {atp - Automatisierungstechnische Praxis}, journal = {atp - Automatisierungstechnische Praxis}, number = {9}, pages = {60 -- 67}, abstract = {Eingebettete Systeme unterliegen neben den funktionalen Anforderungen besonders nicht funktionalen Qualit{\"a}tsanforderungen wie Effizienz, Zuverl{\"a}ssigkeit und Echtzeitf{\"a}higkeit. Mit steigendem Bedarf an Rechenkapazit{\"a}t k{\"o}nnen bisherige Konzepte zur Leistungssteigerung von Singlecore-Systemen jedoch nicht mehr eingesetzt werden - der Umstieg auf Multicore-Systeme wird erforderlich. Im ersten Teil dieser Arbeit werden eine m{\"o}gliche Prozessorarchitektur f{\"u}r zuk{\"u}nftige Automotive Multicore-Systeme und die Abstraktion der Software f{\"u}r diese Systeme vorgestellt. Nach einer Klassifkation von Multicore-Scheduling-Algorithmen pr{\"a}sentieren wir exemplarisch einen Algorithmus mit statischer Taskallokation und einen Algorithmus mit dynamischer Taskallokation. Bei beiden Algorithmen handelt es sich um eine {\"U}berf{\"u}hrung theoretisch behandelter Algorithmen auf Automotive Systeme.}, language = {de} } @inproceedings{SchorerKuntzMottok, author = {Schorer, Michael and Kuntz, Stefan and Mottok, J{\"u}rgen}, title = {Verification of Behavioral Compatibility in the Virtual Integration Methodology}, series = {8th IEEE Workshop on Intelligent Solutions in Embedded Systems,Heraklion, Greece, July 2010}, booktitle = {8th IEEE Workshop on Intelligent Solutions in Embedded Systems,Heraklion, Greece, July 2010}, doi = {10.1109/WISES.2010.5548424}, pages = {35 -- 42}, abstract = {The advantages of component-based systems include reuse of generic components as well as adaption through variants. However, they bare a high risk of containing incompatibilities between components, due to the lack of control over the integration-relevant aspects of their components. Current development processes are able to detect incompatibilities between components only at very late stages of system development. The Virtual Integration methodology is an approach to detect and to solve compatibility issues during early stages of system design. The methodology supports developers with a set of measures to reduce the risk of incompatibilities to a minimum at each abstraction layer of their system architecture. Realtime requirements of embedded systems make it necessary to support the methodology with a formal model, which can describe dynamic properties of these systems. In our approach, we use interface automata because they offer a lightweight formalism to describe the behavior of components and to verify their compatibility based on these descriptions. In a feasibility study we show, to which extend interface automata are adequate for the foresaid purpose in the automotive application field.}, language = {en} } @article{DeubzerSchillerMottoketal., author = {Deubzer, Michael and Schiller, Frank and Mottok, J{\"u}rgen and Niemetz, Michael and Margull, Ulrich}, title = {Effizientes Multicore-Scheduling in Eingebetteten Systemen - Teil 2: Ein simulationsbasierter Ansatz zum Vergleich von Scheduling-Algorithmen}, series = {atp - Automatisierungstechnische Praxis}, volume = {52}, journal = {atp - Automatisierungstechnische Praxis}, number = {10}, abstract = {Eingebettete Systeme unterliegen neben den funktionalen Anforderungen besonders nichtfunktionalen Qualit{\"a}tsanforderungen wie Effizienz, Zuverl{\"a}ssigkeit und Echtzeitf{\"a}higkeit. Mit steigendem Bedarf an Rechenkapazit{\"a}t k{\"o}nnen bisherige Konzepte zur Leistungssteigerung von Singlecore-Systemen jedoch nicht mehr eingesetzt werden - der Umstieg auf Multicore-Systeme wird erforderlich. Im zweiten Teil dieser Arbeit wird ein simulationsbasierter Ansatz zum Vergleich von Multicore-Scheduling-Algorithmen vorgestellt, mit dem Algorithmen f{\"u}r Multicore-Systeme mit voller Migration und dynamischer Task-Priorit{\"a}t untersucht werden. Wir erweitern diesen Ansatz um ein Verfahren zur Untersuchung einer Tasksetmenge mit stochastisch beschriebenen Eigenschaften und vergleichen ihn mit den im Teil 1 beschriebenen Algorithmen BinPacking-EDF und P-ERfair-PD² f{\"u}r eine Gruppe von Automotive Powertrain Systemen.}, language = {de} } @inproceedings{DeubzerMargullMottoketal., author = {Deubzer, Michael and Margull, Ulrich and Mottok, J{\"u}rgen and Niemetz, Michael and Wirrer, Gerhard}, title = {Partly Proportionate Fair Multiprocessor Scheduling of Heterogeneous Task Systems}, series = {5th Embedded Real Time Software and Systems Conference, May 2010}, booktitle = {5th Embedded Real Time Software and Systems Conference, May 2010}, abstract = {Proportionate fair (Pfair) scheduling, which allows task migration at runtime and assigns each task processing time with regard to its weight, is one of the most efficient group of SMP multiprocessor scheduling algorithms known up to now. Drawbacks are tight requirements to the task system, namely the restriction to periodic task systems with synchronized task activation, quantized task execution time, and implicit task deadline. Most likely, a typical embedded real-time system does not fulfill these requirements. In this paper we address violations of these requirements. For heterogeneous task systems, we define the multiple time base (MTB) task system, which is a less pessimistic model than sporadic task systems and is used for automotive systems. We apply the concept of Pfair scheduling to MTB task systems, called partly proportionate fair (Partly-Pfair) scheduling. The restrictions on MTB task systems required for Partly-Pfair ness are weaker than restrictions on periodic task systems required for Pfair ness. In a simulation based study we examined the performance of Partly-Pfair-PD and found it capable to schedule feasible MTB task sets causing a load of up to 100\% of the system capacity.}, language = {en} } @inproceedings{BaerwaldHauffMottok, author = {B{\"a}rwald, Andreas and Hauff, Harald and Mottok, J{\"u}rgen}, title = {Qualification and Certification of Development Tools for Safety-Critical Applications}, series = {Automotive Safety \& Security}, booktitle = {Automotive Safety \& Security}, pages = {135 -- 149}, abstract = {This paper presents an overview on qualification and certification of tools used in the phases of the safety lifecycle for safety-critical applications, either for development or for verification and validation. Software development tools are widely used in the development of safety-critical software systems. More verification and validation procedures will be automated by software tools to reduce time consuming manual testing. The impact of software tools on functional safety is discussed. Based on normative regulations like IEC 61508 and ISO DIS 26262 different approaches for tool qualification and certification are presented.}, language = {en} } @inproceedings{SteindlMottokMeier, author = {Steindl, Michael and Mottok, J{\"u}rgen and Meier, Hans}, title = {SES-based Framework for Fault-tolerant Systems}, series = {8th IEEE Workshop on Intelligent Solutions in Embedded Systems, Heraklion, Greece, July 2010}, booktitle = {8th IEEE Workshop on Intelligent Solutions in Embedded Systems, Heraklion, Greece, July 2010}, doi = {10.1109/WISES.2010.5548427}, pages = {12 -- 16}, abstract = {Embedded real-time systems are often used in harsh environments, for example engine control systems in automotive vehicles. In such ECUs (Engine Control Unit) faults can lead to serious accidents. In this paper we propose a safety embedded architecture based on coded processing. This framework only needs two channels to provide fault tolerance and allows the detection and identification of permanent and transient faults. Once a fault is detected by an observer unit the SES guard makes it visible and initiates a suitable failure reaction.}, language = {en} } @article{BaerwaldHauffMottok, author = {B{\"a}rwald, Andreas and Hauff, Harald and Mottok, J{\"u}rgen}, title = {Certification of safety relevant systems - Benefits of using pre-certified components}, series = {Automotive Safety and Security}, journal = {Automotive Safety and Security}, language = {en} } @inproceedings{StappertJonssonMottoketal., author = {Stappert, Friedhelm and Jonsson, Jan and Mottok, J{\"u}rgen and Johansson, Rolf}, title = {A Design Framework for End-to-End Timing Constrained Automotive}, series = {5th Embedded Real Time Software and Systems Conference (ERTS2 2010), May 2010, Toulouse, France}, booktitle = {5th Embedded Real Time Software and Systems Conference (ERTS2 2010), May 2010, Toulouse, France}, language = {en} } @inproceedings{KraemerMottokMeier, author = {Kr{\"a}mer, Stefan and Mottok, J{\"u}rgen and Meier, Hans}, title = {Osek-basierende Implementierung des LLREF-Scheduling-Algorithmus f{\"u}r eine Dual-Core-Architektur}, series = {2. Landshuter Symposium Mikrosystemtechnik, Tagungsband, 24. une 25. Februar 2010, Hochschule Landshut}, booktitle = {2. Landshuter Symposium Mikrosystemtechnik, Tagungsband, 24. une 25. Februar 2010, Hochschule Landshut}, pages = {343 -- 349}, language = {de} } @inproceedings{SteindlMottokMeieretal., author = {Steindl, Michael and Mottok, J{\"u}rgen and Meier, Hans and Schiller, Frank and Fr{\"u}chtl, M.}, title = {Safeguarded Processing of Sensor Data}, series = {5th Embedded Real Time Software and Systems Conference (ERTS2 2010), May 2010, Toulouse, France}, booktitle = {5th Embedded Real Time Software and Systems Conference (ERTS2 2010), May 2010, Toulouse, France}, language = {en} } @inproceedings{RaabKraemerMottok, author = {Raab, Peter and Kr{\"a}mer, Stefan and Mottok, J{\"u}rgen}, title = {Cyclic codes and error detection during data processing in embedded software systems}, series = {Proceedings of the 4rd Embedded Software Engineering Congress (ESE), 5.-9. Dezember 2011, Sindelfingen}, booktitle = {Proceedings of the 4rd Embedded Software Engineering Congress (ESE), 5.-9. Dezember 2011, Sindelfingen}, pages = {577 -- 590}, language = {en} } @article{BaerwaldHauffMottok, author = {B{\"a}rwald, Andreas and Hauff, Harald and Mottok, J{\"u}rgen}, title = {Qualifizierung und Zertifizierung von Software-Entwicklungswerkzeugen}, series = {Hanser Automotive}, journal = {Hanser Automotive}, pages = {34 -- 39}, language = {de} } @article{KraemerMottokMeier, author = {Kr{\"a}mer, Stefan and Mottok, J{\"u}rgen and Meier, Hans}, title = {Multi-Core Scheduling in Embedded Systemen, Teil 1}, series = {Hanser Automotive}, journal = {Hanser Automotive}, number = {1-2}, pages = {18 -- 22}, language = {en} } @article{KraemerMottokMeier, author = {Kr{\"a}mer, Stefan and Mottok, J{\"u}rgen and Meier, Hans}, title = {Multi-Core Scheduling in Embedded Systemen, Teil 2}, series = {Hanser Automotive}, journal = {Hanser Automotive}, number = {3-4}, pages = {23 -- 25}, language = {en} } @article{KraemerMottokMeier, author = {Kr{\"a}mer, Stefan and Mottok, J{\"u}rgen and Meier, Hans}, title = {Multi-Core Scheduling in Embedded Systemen, Teil 3}, series = {Hanser Automotive}, journal = {Hanser Automotive}, number = {5-6}, pages = {14 -- 16}, language = {en} } @inproceedings{MottokGardeia, author = {Mottok, J{\"u}rgen and Gardeia, Armin}, title = {The regensburg concept of p-seminars - how to organize the interface between secondary school and university education to create a didactic cooperation between teaching and learning of software engineering with lego mindstorms nxt embedded robot systems}, series = {2011 IEEE Global Engineering Education Conference (EDUCON), Amman, Jordan, 2011}, booktitle = {2011 IEEE Global Engineering Education Conference (EDUCON), Amman, Jordan, 2011}, doi = {10.1109/EDUCON.2011.5773255}, pages = {917 -- 920}, abstract = {This paper describes the background and the theory of the learning arrangement "The Regensburg Concept of P 1 - Seminars" and its potential fields of application. This conception was designed to meet the various requirements caused by the Bologna Accords and the restructuring of the senior years of German secondary school education. At the same time it aims at finding solutions for a severe problem topical in Germany: the lack of students qualifying in MINT (the fields of mathematics, informatics, natural sciences and techniques.) The focus of this conception is on the cooperation between universities and schools hence a draft of the P-Seminar has already been realized and evaluated during a pilot phase at a local secondary school. These experiences serve as a solid basis for the development of a concrete plan that makes it possible to transfer the concept to similar projects in future. In the following paragraphs keywords that are applied to the lexical field of the Regensburg Concept are elaborated e.g. "practive learning", an interaction of practical and active learning.}, language = {en} } @inproceedings{RaabKraemerMottoketal., author = {Raab, Peter and Kr{\"a}mer, Stefan and Mottok, J{\"u}rgen and Meier, Hans and Racek, Stanislav}, title = {Safe software processing by concurrent execution in a real-time operating system}, series = {16th International Conference on Applied Electronics (AE 2011), 2011, Pilsen, Czech Republic}, booktitle = {16th International Conference on Applied Electronics (AE 2011), 2011, Pilsen, Czech Republic}, pages = {315 -- 319}, abstract = {The requirements for safety-related software systems increases rapidly. To detect arbitrary hardware faults, there are applicable coding mechanism, that add redundancy to the software. In this way it is possible to replace conventional multi-channel hardware and so reduce costs. Arithmetic codes are one possibility of coded processing and are used in this approach. A further approach to increase fault tolerance is the multiple execution of certain critical parts of software. This kind of time redundancy is easily realized by the parallel processing in an operating system. Faults in the program flow can be monitored. No special compilers, that insert additional generated code into the existing program, are required. The usage of multi-core processors would further increase the performance of such multi-channel software systems. In this paper we present the approach of program flow monitoring combined with coded processing, which is encapsulated in a library of coded data types. The program flow monitoring is indirectly realized by means of an operating system.}, language = {en} } @inproceedings{SchmidhuberDeubzerMottok, author = {Schmidhuber, Stefan and Deubzer, Michael and Mottok, J{\"u}rgen}, title = {Parallelisierte Echtzeitanalyse von Eingebetteten Systemen}, series = {Proceedings of the 4rd Embedded Software Engineering Congress (ESE), 5.-9. Dezember 2011, Sindelfingen}, booktitle = {Proceedings of the 4rd Embedded Software Engineering Congress (ESE), 5.-9. Dezember 2011, Sindelfingen}, pages = {516 -- 524}, language = {de} } @inproceedings{Mottok, author = {Mottok, J{\"u}rgen}, title = {Storytelling: Finite state machines Lernen leicht gemacht!}, series = {Proceedings of the 4rd Embedded Software Engineering Congress (ESE), 5.-9. Dezember 2011, Sindelfingen}, booktitle = {Proceedings of the 4rd Embedded Software Engineering Congress (ESE), 5.-9. Dezember 2011, Sindelfingen}, language = {de} } @inproceedings{Mottok, author = {Mottok, J{\"u}rgen}, title = {General purpose computing on graphics processing unit by using cuda}, series = {Applied Research Conference 2011 (ARC 2011), 6. April, Regensburg}, booktitle = {Applied Research Conference 2011 (ARC 2011), 6. April, Regensburg}, language = {en} } @inproceedings{Mottok, author = {Mottok, J{\"u}rgen}, title = {Ses and the iso 26262}, series = {Applied Research Conference 2011 (ARC 2011), 6. April, Regensburg}, booktitle = {Applied Research Conference 2011 (ARC 2011), 6. April, Regensburg}, language = {en} } @inproceedings{LaloDeubzerSchmidhuberetal., author = {Lalo, Erjola and Deubzer, Michael and Schmidhuber, Stefan and Oklapi, Erna and Mottok, J{\"u}rgen}, title = {Task Priority Optimization in Real-Time Multi-Core Embedded Systems}, series = {4. Landshuter Symposium Mikrosystemtechnik, Mikrosystemtechnik als Schl{\"u}sseltechnologie der Systemintegration, Tagungsband zum Symposium 12./13. M{\"a}rz 2014, Hochschule Landshut}, booktitle = {4. Landshuter Symposium Mikrosystemtechnik, Mikrosystemtechnik als Schl{\"u}sseltechnologie der Systemintegration, Tagungsband zum Symposium 12./13. M{\"a}rz 2014, Hochschule Landshut}, address = {Landshut}, isbn = {978-3-9812696-5-9}, pages = {96 -- 109}, abstract = {The shift from single-core to multi-core processors in real-time embedded systems leads to communication based effects on timing such as inter-core communication delays and blocking times. Moreover, the complexity of the scheduling problem increases when multi-core processors are used. In priority-based-scheduling, a fixed priority assignment is used in order to enable predictable behavior of the system. Predictability means that the system has to be analyzable which allows the detection of problems coming from scheduling decisions. For fixed priority scheduling in multi-core real-time embedded systems, a proper task priority assignment has to be done in a way that the system has minimal effects on timing. In this paper, we present an approach for finding near-optimal solutions for task priority assignment and the preemption/cooperation problem. A genetic algorithm is hereby used to create priority assignment solutions. A timing simulator is used for evaluation of each solution regarding real-time properties, memory consumption and communication overhead. In a case study we demonstrate that the proposed approach performs better than well known and single-core optimal heuristics for relatively complex systems.}, language = {de} } @inproceedings{AltmannBirknerHaeckletal., author = {Altmann, Andreas and Birkner, Wolfgang and H{\"a}ckl, Franz-Xaver and Hanner, Christopher and Liebhart, Peter and Metschl, Samuel and Weck, Florian and Farmbauer, Michael and Heiß, Manfred and Cuno, H.-H. and Fuhrmann, Thomas and Mandl, Roland and Mottok, J{\"u}rgen and Niemetz, Michael}, title = {Payload development and launch of a stratosphere balloon mission}, series = {IEEE Global Engineering Education Conference (EDUCON 2014), 3-5 April 2014, Istanbul, Turkey}, booktitle = {IEEE Global Engineering Education Conference (EDUCON 2014), 3-5 April 2014, Istanbul, Turkey}, doi = {10.1109/EDUCON.2014.6826065}, abstract = {During a student project a stratosphere balloon was developed and launched. This project included the definition of the balloon parameters and the scientific instruments for performing atmospheric measurements, the development of all mechanical and electronic parts, the administration of the project as well as the management tasks related to the balloon launch. The main challenge for the students was the high complexity of the project due to tasks involving many different knowledge domains and the long project duration from the initial definition to the launch.}, language = {en} } @article{RaabKraemerMottoketal., author = {Raab, Peter and Kr{\"a}mer, Stefan and Mottok, J{\"u}rgen and Vavricka, Vlastimil}, title = {Isomorphism between Linear Codes and Arithmetic Codes for Safe Data Processing in Embedded Software Systems}, series = {Computing and Informatics (CAI)}, volume = {33}, journal = {Computing and Informatics (CAI)}, pages = {721 -- 734}, abstract = {We present a transformation rule to convert linear codes into arithmetic codes. Linear codes are usually used for error detection and correction in broadcast and storage systems. In contrast, arithmetic codes are very suitable for protection of software processing in computer systems. This paper shows how to transform linear codes protecting the data stored in a computer system into arithmetic codes safeguarding the operations built on this data. Combination of the advantages of both coding mechanisms will increase the error detection capability in safety critical applications for embedded systems by detection and correction of arbitrary hardware faults.}, language = {en} } @inproceedings{KraemerRaabMottoketal., author = {Kr{\"a}mer, Stefan and Raab, Peter and Mottok, J{\"u}rgen and Racek, Stanislav}, title = {Comparison of Enhanced Markov Models and Discrete Event Simulation}, series = {17th Euromicro Conference on Digital System Design (DSD), 27-29 August 2014, Verona, Italy}, booktitle = {17th Euromicro Conference on Digital System Design (DSD), 27-29 August 2014, Verona, Italy}, doi = {10.1109/DSD.2014.42}, pages = {591 -- 598}, abstract = {In this paper we present simulation and model based approaches for evaluating and validating the temporal and safety relevant properties of software intensive safety-critical real-time embedded systems. A high level reliability model of a safe task execution is described by a continuous-time Markov process, enhanced by the modeling of execution times. It is shown that the behavior - regarding real-time and safety metrics - of this theoretical model can be transferred into an abstract system timing model, which then can be analyzed by a discrete event simulation approach. The verification of the discrete event simulation by Markov models offers the possibility of a holistic approach for reliability analysis combined with schedulability analysis of complex safety-critical multicore real-time systems by the discrete event simulation.}, language = {en} } @inproceedings{MottokScharfenberg, author = {Mottok, J{\"u}rgen and Scharfenberg, Georg}, title = {Forschendes Lernen im Masterstudiengang Applied Research in Engineering Sciences}, series = {4th Applied Research Conference, 5th July 2014, Ingolstadt}, booktitle = {4th Applied Research Conference, 5th July 2014, Ingolstadt}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-2875-1}, pages = {55 -- 61}, language = {de} } @inproceedings{ScharfenbergMottok, author = {Scharfenberg, Georg and Mottok, J{\"u}rgen}, title = {Forschungsmaster entwickelt sich zum Wirtschaftsfaktor in Bayern}, series = {4th Applied Research Conference, 5th July 2014, Ingolstadt}, booktitle = {4th Applied Research Conference, 5th July 2014, Ingolstadt}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-2875-1}, pages = {55 -- 61}, language = {de} } @inproceedings{GschossmannJobstMottoketal., author = {Gschossmann, Andreas and Jobst, Simon and Mottok, J{\"u}rgen and Bierl, Rudolf}, title = {A Measure of Confidence of Artificial Neural Network Classifiers}, series = {ARCS Workshop 2019; 32nd International Conference on Architecture of Computing Systems, 20-21 May 2019, Copenhagen, Denmark}, booktitle = {ARCS Workshop 2019; 32nd International Conference on Architecture of Computing Systems, 20-21 May 2019, Copenhagen, Denmark}, publisher = {VDE-Verlag}, address = {Berlin}, pages = {153 -- 157}, abstract = {Confidence in results of an Artificial Neural Networks (ANNs) is increased by preferring to reject data, that is not trustful, instead of risking a misclassification. For this purpose a model is proposed that is able to recognize data, which differs significantly from the training data, during inference. The proposed model observes all activations of the hidden layers, as well as input and output layers of an ANN in a grey-box view. To make ANNs more robust in safety critical applications, this model can be used to reject flawed data, that is suspected to decrease the accuracy of the model. If this information is logged during inference, it can be used to improve the model, by training it specifically with the missing information. An experiment on the MNIST dataset is conducted and its results are discussed.}, language = {en} } @inproceedings{SchmidhuberDeubzerMaderetal., author = {Schmidhuber, Stefan and Deubzer, Michael and Mader, Ralph and Niemetz, Michael and Mottok, J{\"u}rgen}, title = {Towards the Derivation of Guidelines for the Deployment of Real-Time Tasks on a Multicore Processor}, series = {4th International Symposium on Model-Based Safety and Assessment (IMBSA 2014), Munich, Germany, October 27-29, 2014, Proceedings}, booktitle = {4th International Symposium on Model-Based Safety and Assessment (IMBSA 2014), Munich, Germany, October 27-29, 2014, Proceedings}, publisher = {Springer}, address = {Munich}, isbn = {978-3-319-12213-7}, doi = {10.1007/978-3-319-12214-4_12}, pages = {152 -- 165}, abstract = {The deployment of automotive software on a multicore processor includes the task of mapping executables to cores. Given the number of possible solutions, integrators have to solve a complex problem. Considering multiple, often conflicting goals like minimizing task response times and memory consumption, complexity further increased with the advent of multicore processors. We present a model-based approach for deriving design rules supporting integrators with statically mapping tasks to a multicore ECU. First, an evolutionary algorithm is used to sample the design space. For each sample, a model-based analysis is performed, resulting in the required fitness values according to the system metric objectives. Finally, subsets of the sample population are used to derive deployment guidelines by evaluating similarities between highly ranked solutions. This reduces the number of solutions to be considered by the integrators by orders of magnitude. In a case-study, we demonstrate the developed approach on an artificial automotive engine management system.}, language = {en} } @inproceedings{KraemerRaabMottoketal., author = {Kr{\"a}mer, Stefan and Raab, Peter and Mottok, J{\"u}rgen and Racek, Stanislav}, title = {Comparison of Enhanced Markov Models and Discrete Event Simulation - for evaluation of probabilistic Faults in safety-critical real-time task sets}, series = {Proceedings of EUROMICRO DSD 2014 - 17th Euromicro Conference on Digital System Design}, booktitle = {Proceedings of EUROMICRO DSD 2014 - 17th Euromicro Conference on Digital System Design}, doi = {10.1109/DSD.2014.42}, pages = {591 -- 598}, abstract = {In this paper we present simulation and model based approaches for evaluating and validating the temporal and safety relevant properties of software intensive safety-critical real-time embedded systems. A high level reliability model of a safe task execution is described by a continuous-time Markov process, enhanced by the modeling of execution times. It is shown that the behavior - regarding real-time and safety metrics - of this theoretical model can be transferred into an abstract system timing model, which then can be analyzed by a discrete event simulation approach. The verification of the discrete event simulation by Markov models offers the possibility of a holistic approach for reliability analysis combined with schedulability analysis of complex safety-critical multicore real-time systems by the discrete event simulation.}, language = {en} } @inproceedings{AlfransederDeubzerJustusetal., author = {Alfranseder, Martin and Deubzer, Michael and Justus, Benjamin and Mottok, J{\"u}rgen and Siemers, Christian}, title = {An Efficient Spin-Lock Based Multi-Core Resource Sharing Protocol}, series = {33rd IEEE International Performance, Computing, and Communications Conference (IPCCC), Austin (TX), USA, 5-7 December 2014}, booktitle = {33rd IEEE International Performance, Computing, and Communications Conference (IPCCC), Austin (TX), USA, 5-7 December 2014}, doi = {10.1109/PCCC.2014.7017090}, abstract = {We present in this paper a new lock-based resource sharing protocol PWLP (Preemptable Waiting Locking Protocol) for embedded multi-core processors. It is based on the busy-wait model and works with non-preemptive critical sections while task may be preempted by tasks with a higher priority when waiting for resources. Our protocol can be applied in partitioned as well as global scheduling scenarios, in which task-fix, job-fix or dynamically assigned priorities may be used. Furthermore, the PWLP permits nested requests to shared resources. Finally, we present a case study based on event-based simulations in which the FMLP (Flexible Multiprocessor Locking Protocol) and the proposed PWLP are compared.}, language = {en} } @inproceedings{AlfransederKrapfMaderetal., author = {Alfranseder, Martin and Krapf, Tobias and Mader, Ralph and Niemetz, Michael and Mottok, J{\"u}rgen and Siemers, Christian}, title = {An Efficient Partitioning Strategy for Runnables in Weakly Dependent Tasks on Embedded Multi-Core Systems}, series = {Embedded real-time software and systems (ERTS² 2014), Feb 2014, Toulouse, France}, booktitle = {Embedded real-time software and systems (ERTS² 2014), Feb 2014, Toulouse, France}, abstract = {With multi-core controllers entering the area of automotive control ECUs, strategies for parallelizing the control- algorithms come into focus. This paper deals with a special part of automotive powertrain software, called state transitions. Since dependencies between runnables executed there are weak, the transitions provide a good basis for parallelization. We present a strategy of how to distribute efficiently the execution of runnables to different cores while taking care of inner and outer dependencies. The strategy is accompanied by two case studies demonstrating the performance of the concept. The first one is carried out to find the most efficient strategies of parallelize state transitions based on randomly generated, simulated state transitions. In the second one, the developed partitioning strategies are applied to a real software project for an automotive powertrain system.}, language = {en} } @inproceedings{HelmDeubzerMottok, author = {Helm, C. and Deubzer, Michael and Mottok, J{\"u}rgen}, title = {Analyse der Echtzeiteigenschaften von Multicore Speicherarchitekturen in Eingebetteten Systemen mittels einer konfigurierbaren Simulationssoftware}, series = {4. Landshuter Symposium Mikrosystemtechnik : Mikrosystemtechnik als Schl{\"u}sseltechnologie der Systemintegration, Tagungsband zum Symposium 12./13. M{\"a}rz 2014, Hochschule Landshut}, booktitle = {4. Landshuter Symposium Mikrosystemtechnik : Mikrosystemtechnik als Schl{\"u}sseltechnologie der Systemintegration, Tagungsband zum Symposium 12./13. M{\"a}rz 2014, Hochschule Landshut}, editor = {Ivanov, Artem and Bicker, Marc and Patzelt, Peter}, address = {Landshut}, isbn = {978-3-9812696-5-9}, pages = {109 -- 117}, language = {de} } @inproceedings{LaloSchmidhuberDeubzeretal., author = {Lalo, Erjola and Schmidhuber, Stefan and Deubzer, Michael and Mottok, J{\"u}rgen}, title = {Extended Task Priority and Preemptability Optimization in Real-Time Multi-Core Embedded Systems}, series = {4th Applied Research Conference, 5th July 2014, Ingolstadt}, booktitle = {4th Applied Research Conference, 5th July 2014, Ingolstadt}, address = {Ingolstadt}, isbn = {978-3-8440-2875-1}, pages = {90 -- 95}, language = {en} } @inproceedings{ThielHacklMottok, author = {Thiel, P. and Hackl, Magnus and Mottok, J{\"u}rgen}, title = {Designing efficient Node.js applications - Approaching useful patterns}, series = {4th Applied Research Conference, 5th July 2014, Ingolstadt}, booktitle = {4th Applied Research Conference, 5th July 2014, Ingolstadt}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-2875-1}, pages = {40 -- 46}, language = {en} } @inproceedings{HacklThielMottok, author = {Hackl, Magnus and Thiel, Patrik and Mottok, J{\"u}rgen}, title = {Not Only SQL - a comparison to traditional RDBMS}, series = {4th Applied Research Conference (ARC 2014), 5th July 2014, Ingolstadt}, booktitle = {4th Applied Research Conference (ARC 2014), 5th July 2014, Ingolstadt}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-2875-1}, language = {en} } @inproceedings{RaabMottok, author = {Raab, Peter and Mottok, J{\"u}rgen}, title = {Modellbasierte Zuverl{\"a}ssigkeitsanalysen von arithmetischen Operationen in einem Prozessorsystem}, series = {Proceedings of safe.tech 2014, 20. und 21. Mai 2014, M{\"u}nchen}, booktitle = {Proceedings of safe.tech 2014, 20. und 21. Mai 2014, M{\"u}nchen}, language = {de} } @inproceedings{OklapiDeubzerSchmidhuberetal., author = {Oklapi, Erna and Deubzer, Michael and Schmidhuber, Stefan and Lalo, Erjola and Mottok, J{\"u}rgen}, title = {Optimization of Real-Time Multicore Systems Reached by a Genetic Algorithm Approach for Runnable Sequencing}, series = {2014 International Conference on Applied Electronics, Pilsen, Czech Republic}, booktitle = {2014 International Conference on Applied Electronics, Pilsen, Czech Republic}, doi = {10.1109/AE.2014.7011709}, pages = {233 -- 238}, abstract = {The deployment of complex real-time systems with everyday increasing demands and possibilities, is a challenging task for engineers when performance and efficiency have to be maximized while cost have to be minimized at the same time. For already designed systems it became necessary to perform different modifications in order to find optimal software architecture configuration by respecting all timing constraints which are essential when speaking of real-time systems. In this work, we present a model-based approach of optimizing the execution sequence of runnables within tasks in order to reduce the system's reaction times by improving the overall signal flow duration. Hereby, a genetic optimization algorithm is used to create and evaluate multiple solutions for the runnable sequencing problem. We conclude by demonstration the efficiency of the presented approach with experimental results.}, language = {en} } @incollection{MottokAlfransederSchmidhuberetal., author = {Mottok, J{\"u}rgen and Alfranseder, Martin and Schmidhuber, Stefan and Mucha, Matthias and Sailer, Andreas}, title = {How to improve the reactiveness and efficiency of embedded multicore systems by use of probabilistic simulation and optimization techniques}, series = {Improving Disaster Resilience and Mitigation - New Means and Tools. NATO Science for Peace and Security Series C: Environmental Security}, booktitle = {Improving Disaster Resilience and Mitigation - New Means and Tools. NATO Science for Peace and Security Series C: Environmental Security}, editor = {Teodorescu, Horia-Nicolai and Kirschenbaum, Alan and Cojocaru, Svetlana and Bruderlein, Claude}, publisher = {Springer}, address = {Dodrecht}, doi = {10.1007/978-94-017-9136-6_16}, pages = {253 -- 268}, abstract = {Safe and reliable multi-core technology becomes more and more important in the field of embedded systems. Today's and future embedded systems require increasing performance while being more energy efficient. Moreover, the functional safety for these embedded systems has to be improved or developed completely new. In this chapter, we first address the challenges of embedded multi-core real-time systems. To raise the resilience of such systems we use the deadlock-free synchronization model of Block et al. (A flexible real-time locking protocol for multiprocessors. 2012 IEEE international conference on embedded and real-time computing systems and applications, vol 0, pp 47-56, 2007). The metric mean Normalized Blocking Time (mNBT) is hereby used to measure the timing effects of the blocking behavior of strongly interacting tasks. In a second step, we present a model-based approach to map the tasks of an embedded real-time system to the cores of a multi-core processor. Moreover, we derive an execution time model from runtime measurements of software functions. This information is then used to perform precise probabilistic simulations of different task-to-core mappings and evaluate them with regard to task response times, inter-task blocking overhead and load distribution. Subsequently, we integrate the probabilistic simulation within an optimization technique to systematically improve the task-to-core mapping. We conclude with a case-study, where we demonstrate the effectiveness of the presented approach by optimizing the task-to-core mapping of a practical automotive powertrain system.}, language = {en} } @inproceedings{SoskaMottok, author = {Soska, Alexander and Mottok, J{\"u}rgen}, title = {A New Conceptual Contribution for Serious Games in Academic Software Engineering Education}, series = {European Conference on Software Engineering Education 2014 (ECSEE), 27 and 28 November 2014 in Seeon Monastery}, booktitle = {European Conference on Software Engineering Education 2014 (ECSEE), 27 and 28 November 2014 in Seeon Monastery}, publisher = {Shaker}, address = {Aachen}, isbn = {978-3-8440-3067-9}, pages = {241 -- 254}, abstract = {Nowadays, the popularity and field of application of serious games grows steadily. This educational method offers attractive pportunities for teaching and training by combining playful elements with learning content. By using game mechanics, thinking and technique, theoretical subject matters are treated in a fun and engaging way. Thereby, serious games utilize our intrinsic motivation to discover the surroundings in a playful manner. Embedded in educational settings, the goal is to mediate academic and non-academic knowledge to the students. Especially in the field of software engineering it is important to have skills which go beyond pure technical knowledge. Yet, the use of serious games is still a manageable amount. With this paper, we give a contribution to the theoretical design and development of serious games based on playful learning method and its relation to research-based learning in universal context. In addi- tion we analyze the existing serious games in software engineering and present our thoughts about planning our own.}, language = {en} } @inproceedings{AlfransederMuchaSchmidhuberetal., author = {Alfranseder, Martin and Mucha, Matthias and Schmidhuber, Stefan and Sailer, Andreas and Niemetz, Michael and Mottok, J{\"u}rgen}, title = {A modified synchronization model for dead-lock free concurrent execution of strongly interacting task sets in embedded systems}, series = {2013 International Conference on Applied Electronics (AE 2013), IEEE, 10-12 September 2013, Pilsen, Czech Republic}, volume = {18}, booktitle = {2013 International Conference on Applied Electronics (AE 2013), IEEE, 10-12 September 2013, Pilsen, Czech Republic}, pages = {13 -- 18}, abstract = {Global scheduling algorithms are very promising for application in embedded real-time systems using multi-core controllers. In this paper we want to make a first step forward to apply such scheduling methods on real existing systems. Especially a new resource model is necessary to avoid deadlocks, as this goal can not be achieved by using the standard OSEK Priority Ceiling Protocol when shared global resources are in use. We also introduce the new metric mean Normalized Blocking Time in order to be able to compare locking mechanisms according to the timing effects of their blocking behavior. Finally we give a simulative application example of the new metric by the use of two different kinds of semaphore models and an example task set typical for existing embedded real-time systems in the automotive powertrain environment.}, language = {en} } @inproceedings{RaabKraemerMottok, author = {Raab, Peter and Kr{\"a}mer, Stefan and Mottok, J{\"u}rgen}, title = {Error Model and the Reliability of Arithmetic Operations}, series = {2013 IEEE EUROCON - International Conference on Computer as a Tool, Zagreb, Croatia, July 1-4, 2013}, booktitle = {2013 IEEE EUROCON - International Conference on Computer as a Tool, Zagreb, Croatia, July 1-4, 2013}, doi = {10.1109/EUROCON.2013.6625047}, pages = {630 -- 637}, abstract = {Error detecting and correcting codes are widely used in data transmission, storage systems and also for data processing. In logical circuits like arithmetic operations, arbitrary faults can cause errors in the result. However in safety critical applications, it is important to avoid those errors which would lead to system failures. Several approaches are known to protect the result of operations during software processing. In the same way like transmission systems, coded processing uses codes for fault detection. But in contrast to transmission systems, there is no adequate channel model available which makes it possible to evaluate the residue error probability of an arithmetic operation in an analytical way. This paper tries to close the gap of arithmetic error models by the development of a model for an ordinary addition in a computer system. Thus, the reliability of an addition's result can be analytically evaluated.}, language = {en} } @inproceedings{RaabRacekKraemeretal., author = {Raab, Peter and Racek, Stanislav and Kr{\"a}mer, Stefan and Mottok, J{\"u}rgen}, title = {Data Flow Analysis of Software Executed by Unreliable Hardware}, series = {16th Euromicro Conference on Digital System Design, Los Alamitos, CA, USA}, booktitle = {16th Euromicro Conference on Digital System Design, Los Alamitos, CA, USA}, doi = {10.1109/DSD.2013.35}, pages = {243 -- 249}, abstract = {The data flow is a crucial part of software execution in recent applications. It depends on the concrete implementation of the realized algorithm and it influences the correctness of a result in case of hardware faults during the calculation. In logical circuits, like arithmetic operations in a processor system, arbitrary faults become a more tremendous aspect in future. With modern manufacturing processes, the probability of such faults will increase and the result of a software's data flow will be more vulnerable. This paper shows a principle evaluation method for the reliability of a software's data flow with arbitrary soft errors also with the concept of fault compensation. This evaluation is discussed by means of a simple example based on an addition.}, language = {en} } @inproceedings{OklapiDeubzerSchmidhuberetal., author = {Oklapi, Erna and Deubzer, Michael and Schmidhuber, Stefan and Mottok, J{\"u}rgen}, title = {Verification of an Evolutionary Optimization Algorithm for Runnable Sequencing Problem}, series = {4th Applied Research Conference, 5th July 2014, Ingolstadt}, booktitle = {4th Applied Research Conference, 5th July 2014, Ingolstadt}, language = {en} } @inproceedings{AlfransederKrapfMottoketal., author = {Alfranseder, Martin and Krapf, Tobias and Mottok, J{\"u}rgen and Siemers, Christian}, title = {Synchronisationsverfahren in embedded Multicoresystemen}, series = {Tagungsband, 6th Embedded Software Engineering, Kongress 2013, 2. bis 6. Dezembern 2013, Sindelfingen}, booktitle = {Tagungsband, 6th Embedded Software Engineering, Kongress 2013, 2. bis 6. Dezembern 2013, Sindelfingen}, publisher = {Vogel Business Media}, address = {W{\"u}rzburg}, language = {de} } @inproceedings{SailerSchmidhuberDeubzeretal., author = {Sailer, Andreas and Schmidhuber, Stefan and Deubzer, Michael and Alfranseder, Martin and Mucha, Matthias and Mottok, J{\"u}rgen}, title = {Optimizing the task allocation step for multi-core processors within autosar}, series = {2013 International Conference on Applied Electronics, IEEE, Pilsen, Czech Republic}, booktitle = {2013 International Conference on Applied Electronics, IEEE, Pilsen, Czech Republic}, abstract = {We present a model-based optimization approach for the task allocation problem in embedded multi-core systems. The information therefore is obtained from a system description in AUTOSAR and runtime measurements of the runnables in hardware traces. Based on this an initial software partitioning of runnables to tasks is created. We then use a genetic algorithm to create and evaluate solutions to the task allocation problem. Each solution is hereby evaluated using a discrete event-based simulation, which allows the evaluation with regard to real-time properties, resource consumption and data-communication overhead. The significance of our approach is then shown in a case-study. There, we optimize the task allocation of an embedded system, whose complexity is comparable to that of an actual system, on a multi-core processor. Finally, the results of the optimization are transferred to an ECU Configuration Description to enable further development in compliance with the AUTOSAR methodology.}, language = {en} } @inproceedings{TomerHagelMottoketal., author = {Tomer, Amir and Hagel, Georg and Mottok, J{\"u}rgen and Alt, Dorit and Barak, Miriam I. and Hadar, Irit}, title = {CAPELLA: A conceptual framework for adaptive life-long learning}, series = {IEEE Global Engineering Education Conference (EDUCON), 25-28 April 2017, Athens, Greece}, booktitle = {IEEE Global Engineering Education Conference (EDUCON), 25-28 April 2017, Athens, Greece}, doi = {10.1109/EDUCON.2017.7943041}, pages = {1463 -- 1472}, abstract = {In this paper we describe a proposed framework for Cooperative Adaptive Personalized Education for Life-long Learning and Activation (CAPELLA). CAPELLA comprises four models: A Knowledge Organization Model, a Learning Process Model, a Community Collaboration Model and a Gaming Model. The underlying pedagogical approach is based on the four pillars of learning: Learning to know, learning to do, learning to collaborate and learning to be. Based on these models and principles, CAPELLA provides a theoretical framework that may assist IT developers to develop state-of-the-art educational platforms and advanced learning applications. Using an example of a UML Diagramming Workshop we demonstrate how CAPELLA incorporates the principles of Adaptive Learning.}, language = {en} } @inproceedings{SchummJosephMottoketal., author = {Schumm, Michael and Joseph, Saskia and Mottok, J{\"u}rgen and Niemetz, Michael and Schroll-Decker, Irmgard}, title = {Lernarrangements im software engineering und deren evaluation - neue konzepte f{\"u}r hochschule und lebenslanges Lernen}, series = {Tagungsband 5th Embedded Software Engineering Kongress, 3. bis 7. Dezember 2012, Sindelfingen}, booktitle = {Tagungsband 5th Embedded Software Engineering Kongress, 3. bis 7. Dezember 2012, Sindelfingen}, language = {de} } @inproceedings{KraemerRaabMottok, author = {Kr{\"a}mer, Stefan and Raab, Peter and Mottok, J{\"u}rgen}, title = {Simulationsbasierte Reliability-Analyse - Einfl{\"u}sse von zuf{\"a}lligen Fehlern auf das Echtzeit-Scheduling}, series = {Tagungsband 5th Embedded Software Engineering Kongress, 3. bis 7. Dezember 2012, Sindelfingen}, booktitle = {Tagungsband 5th Embedded Software Engineering Kongress, 3. bis 7. Dezember 2012, Sindelfingen}, pages = {613 -- 622}, language = {de} }