6 research outputs found

    Ontology-based Analysis and Scalable Model Checking of Embedded Systems Models

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    Currently, there is lack of effective and scalable methods to specify and ana-lyze requirements specifications, and verify the behavioral models of embed-ded systems. Most embedded systems requirements are expressed in naturallanguage which is flexible and intuitive but frequently ambiguous, vague andincomprehensive. Besides to natural language, template-based requirementsspecification methods are used to specify requirements specifications (esp. insafety-critical applications), which reduce ambiguity and improves the com-prehensibility of the specifications. However, the template-based method areusually rigid due to the fixed structures of the templates. They also lack meta-models for extensibility, and template selection is challenging.In this thesis, we proposed a domain specific language for embedded sys-tems, called ReSA, which is constrained natural language but flexible enoughto allow engineers to use different constructs to specify requirements. Thelanguage has formal semantics in proportional logic and description logic thatenables non-trivial and rigorous analysis of requirements specification, e.g.,consistency checking, completeness of specifications, etc.Moreover, we propose a scalable formal verification of Simulink models,whichisusedtodescribethebehaviorofsystemsthroughcommunicatingfunc-tional blocks. In industry, Simulink is the de facto modeling and analysis en-vironment of embedded systems. It is also used to generate code automati-cally from special Simulink models for various hardware platforms. However,Simulink lacks formal approach to verify large and hybrid Simulink models.Therefore, we also propose a formal verification of Simulink models, repre-sented as stochastic timed automata, using statistical model checking, whichhas proven to scale for industrial applications.We validate our approaches on industrial use cases from the automotiveindustry. These includes Adjustable Speed Limiter (ASL) and Brake-By-Wire(BBW) systems from Volvo Group Trucks Technology, both safety-critical.Verispe

    Extending Real-Time component-based Framework to Virtual Nodes : Demonstration: Automated Orchestra real-time Application

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    Industrial control systems are applied in many areas e.g., motion control for industrial robotics, process control of large plants such as in the area of oil and gas, and in large national power grids. Since the last decade with advancement and adoption of virtualization and multicore technology (e.g., Virtual Monitoring Machine, cloud computing, server virtualization, application virtualization), IT systems, automation industries have benefited from low investment, effective system management and high service availability. However, virtualization and multicore technologies have posed a serious challenge to real-time systems, which is violating timeliness and predictability of real-time application running on control systems. To address the challenge, we have extended a real-time component-based framework with virtual nodes; and evaluated the framework in the context of virtualized multicore environment. The evaluation is demonstrated by modeling and implementing an orchestra application with QoS for CPU, memory and network bandwidth. The orchestra application is a real-time and distributed application deployed on virtualized multicore PCs connected with speakers. The result shows undistorted orchestra performance played through speakers connected to physical computer nodes. The contribution of the thesis can be considered: 1) extending a real-time component-based framework, Future Automation Software Architecture (FASA) with virtual nodes using Virtual Computation Resource (VCR) and 2) design and installation of reusable test environment for development, debugging and testing of real-time application on a network of virtualized multicore environment. Vinnova project “AUTOSAR for Multi-Core in Automotive and Automation Industries

    Design of Assured and Efficient Safety-critical Systems

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    Safety-critical   systems   need   to   be   analyzed rigorously to remove software/specifications errors, that is, their requirements specifications should be unambiguous, comprehensible and consistent, and the software design should conform to the specifications, hence avoiding undesirable system failures. Currently, there is a lack of effective and scalable methods to specify and analyze requirements, and formally analyze the behavioral models of embedded systems. Most embedded systems requirements are expressed in natural language, which is flexible and intuitive but frequently ambiguous and incomprehensible.  Besides natural language, template-based requirements specification methods are used frequently to specify requirements (esp.  in safety-critical applications).  Although the latter reduce ambiguity and improve the comprehensibility of the specifications, they are usually rigid due to the constrained syntax of the templates, and template selection is challenging.  Industrial systems are frequently developed by using modeling and simulation environments such as Simulink, which is also used to generate code automatically for various hardware platforms. Therefore, it is essential to be able to formally analyze Simulink models, to get insight into the behavior of the embedded system, and also prevent potential errors from propagating into the implementation.  Analyzing the timing behavior of safety-critical software that is refined by multi-rate periodic tasks with data age constraints across the end-to-end software functionality is not trivial. This is due to the undersampling and oversampling effects caused by the data propagation from higher to lower rates and vice versa, respectively. Furthermore, when such systems are deployed on a distributed architecture, e.g., electrical/electronic vehicular system, besides assuring the timeliness, the reliability of the distributed software should be maximized to counter the higher risk of failures in the distributed computing setting, hence improving the overall predictability of the safety-critical system. However, designing for reliability usually requires additional critical system resources such as energy.  Hence, to accommodate the growing complexity of software functionality, the design of the safety-critical systems should consider the efficient use of critical system resources such as the power source, while meeting the timing and reliability requirements. To address the above needs, in this thesis, we propose formal-methods-based approaches and optimization techniques to assure improved quality of requirements specifications and software designs, and to efficiently map software functionality to hardware. The contributions of the thesis are: (i) ReSA - a domain-specific requirements specification  language tailored to embedded systems, based on constrained natural language; (ii) a formal approach to check consistency of ReSA specifications via Boolean satisfiability problem (SAT) and ontology; (iii) a framework based on statistical model checking to analyze Simulink models via automated transformation into networks of stochastic timed automata; and (iv) a resource-efficient allocation of fault-tolerant software with end-to-end timing and reliability constraints via integer linear programming and hybrid particle-swarm optimization. Our proposed solutions are validated and evaluated on automotive use cases such as the Adjustable Speed Limiter (ASL) and the Brake-by-Wire (BBW) systems from Volvo Group Trucks Technology (VGTT), and on an Engine Management (EM) system benchmark from Bosch.  SĂ€kerhetskritiska system bör analyseras noggrant för att ta bort fel i programvaror och specifikationer, dvs systemens krav mĂ„ste vara entydiga, begripliga och konsekventa, och programvarudesignen ska överensstĂ€mma med specifikationerna för att undvika oönskade systemfel. För nĂ€rvarande saknas effektiva och skalbara metoder för att specificera och analysera systemkrav, och för att formellt analysera beteendemodellerna för inbyggda system. De flesta krav för inbyggda system uttrycks i naturligt sprĂ„k, vilket Ă€r flexibelt och intuitivt men ofta tvetydigt och oprecist. Förutom naturligt sprĂ„k anvĂ€nds ofta mallbaserade kravspecifikationsmetoder för att specificera krav (speciellt i sĂ€kerhetskritiska tillĂ€mpningar). Även om de senare minskar otydligheten och förbĂ€ttrar begripligheten, Ă€r de vanligtvis oflexibla pĂ„ grund av den begrĂ€nsade syntaxen i mallarna, och mallvalet Ă€r svĂ„rt. Industriella system utvecklas ofta genom att anvĂ€nda modellerings- och simuleringsmiljöer sĂ„som Simulink, som ocksĂ„ anvĂ€nds för att generera kod automatiskt för olika hĂ„rdvaruplattformar. DĂ€rför Ă€r det viktigt att kunna formellt analysera Simulink-modeller, för att fĂ„ insikt i beteendet hos det inbyggda systemet, och för att förhindra potentiella fel frĂ„n att sprida sig till implementationen. Att analysera tidsperspektivet för sĂ„dan sĂ€kerhetskritisk mjukvara som har tasks med olika periodicitet och som har begrĂ€nsningar pĂ„ datas Ă„lder, dvs datans fĂ€rskhet, för end-to-end-programvarufunktionalitet, Ă€r inte trivialt. Detta orsakas av undersamplings- och översamplingseffekter, som uppstĂ„r nĂ€r data gĂ„r frĂ„n högre till lĂ€gre signaleringshastigheter och vice versa. Vidare, nĂ€r sĂ„dana system anvĂ€nds i en distribuerad arkitektur, t.ex. elektriska / elektroniska fordonssystem, , sĂ„ bör, förutom att sĂ€kerstĂ€lla tidskraven, Ă€ven tillförlitligheten hos den distribuerade mjukvaran maximeras för att motverka den högre risken för fel i den distribuerade databehandlingen, för att dĂ€rigenom förbĂ€ttra den övergripande förutsĂ€gbarheten för det sĂ€kerhetskritiska systemet. Design för tillförlitlighet krĂ€ver emellertid vanligtvis mer av kritiska systemresurser, sĂ„som energi. För att tillgodose nuvarande och framtida mjukvarufunktionalitet bör utformningen av det sĂ€kerhetskritiska systemet ta hĂ€nsyn till effektiviteten hos kritiska systemresurser, sĂ„som energiförbrukning, samtidigt som kraven pĂ„ tid och tillförlitlighet uppfylls. För att möta ovanstĂ„ende behov, föreslĂ„r vi i denna avhandling formella metoder och optimeringstekniker för att sĂ€kerstĂ€lla förbĂ€ttrad kvalitet pĂ„ kravspecifikationer och mjukvaruutveckling, och för att effektivt mappa mjukvarufunktionalitet till hĂ„rdvara. Avhandlingens bidrag Ă€r: (i) \textit{ReSA} - ett domĂ€nspecifikt sprĂ„k för kravspecifikation, skrĂ€ddarsytt för inbyggda system, baserat pĂ„ begrĂ€nsat naturligt sprĂ„k; (ii) ett formellt tillvĂ€gagĂ„ngssĂ€tt för att kontrollera konsistensen av \textit{ReSA}-specifikationer genom SAT och Ontologi; (iii) ett ramverk baserat pĂ„ statistisk modellkontroll för att analysera Simulink-modeller via automatiserad omvandling till nĂ€tverk av stokastiska tidsautomater; och (iv) en resurseffektiv fördelning av feltolerant programvara med end-to-end-tidskrav och driftsĂ€kerhetsbegrĂ€nsningar genom heltals-linjĂ€r programmering och hybrid partikel-svĂ€rmoptimering. VĂ„ra föreslagna lösningar utvĂ€rderas i fall som anvĂ€nds i fordon, sĂ„som justerbar hastighetsbegrĂ€nsare (ASL) och BBW-system frĂ„n Volvo Group Trucks Technology (VGTT), och pĂ„ ett motorstyrsystem frĂ„n Bosch.VeriSpe

    Kronika polska Galla Anonima w kontekƛcie ksztaƂtowania się polskiej ƛwiadomoƛci narodowej

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    Gallus Anonymus’ gesta principium polonorum in the context of the formation of Polish national consciousness This paper is an attempt at a reconstruction of sources of Polish national consciousness, with its political and cultural components. It should be emphasized that cultural determinants are most important for consolidating national identity. In the Polish case, one of the most interesting and also most often reproduced Polish cultural motifs is the legend of Piast and Popiel. For reasons outlined above, this article will attempt to analyze legends of the first ruler in Poland and references to them in the contemporary Polish culture. For clarity of analysis, the essay is divided into two parts. The first is connected with the myth of richness and the fertile, as well as powerful Poland. The significance of this part is for the processes of creating Polish national identity around utopian visions, and also their presence in the literature. Furthermore, this myth is related with belief that the ruler must be just for his people. The second part includes the analysis of the presence of this myth in popular culture, on the example of children’s literature and in the social space
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