{"title":"Input Synthesis for Sampled Data Systems by Program Logic","authors":"Takumi Akazaki, I. Hasuo, Kohei Suenaga","doi":"10.4204/EPTCS.174.3","DOIUrl":"https://doi.org/10.4204/EPTCS.174.3","url":null,"abstract":"Inspired by a concrete industry problem we consider the input synthesis problem for hybrid systems: given a hybrid system that is subject to input from outside (also called disturbance or noise), find an input sequence that steers the system to the desired postcondition. In this paper we focus on sampled data systems--systems in which a digital controller interrupts a physical plant in a periodic manner, a class commonly known in control theory--and furthermore assume that a controller is given in the form of an imperative program. We develop a structural approach to input synthesis that features forward and backward reasoning in program logic for the purpose of reducing a search space. Although the examples we cover are limited both in size and in structure, experiments with a prototype implementation suggest potential of our program logic based approach.","PeriodicalId":360438,"journal":{"name":"HAS","volume":"23 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129608486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Safe Neighborhood Computation for Hybrid System Verification","authors":"Yi Deng, A. Julius","doi":"10.4204/EPTCS.174.1","DOIUrl":"https://doi.org/10.4204/EPTCS.174.1","url":null,"abstract":"For the design and implementation of engineering systems, performing model-based analysis can disclose potential safety issues at an early stage. The analysis of hybrid system models is in general difficult due to the intrinsic complexity of hybrid dynamics. In this paper, a simulation-based approach to formal verification of hybrid systems is presented.","PeriodicalId":360438,"journal":{"name":"HAS","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132099618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Modeling Populations of Thermostatic Loads with Switching Rate Actuation","authors":"L. Totu, R. Wisniewski, J. Leth","doi":"10.4204/EPTCS.174.2","DOIUrl":"https://doi.org/10.4204/EPTCS.174.2","url":null,"abstract":"We model thermostatic devices using a stochastic hybrid description, and introduce an external actuation mechanism that creates random switch events in the discrete dynamics. We then conjecture the form of the Fokker-Planck equation and successfully verify it numerically using Monte Carlo simulations. The actuation mechanism and subsequent modeling result are relevant for power system operation.","PeriodicalId":360438,"journal":{"name":"HAS","volume":"22(2) 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116540412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Combinatorial Abstractions of Dynamical Systems","authors":"R. Wisniewski","doi":"10.4204/EPTCS.124.2","DOIUrl":"https://doi.org/10.4204/EPTCS.124.2","url":null,"abstract":"Formal verification has been successfully developed in computer science for verifying combinatorial classes of models and specifications. In like manner, formal verification methods have been developed for dynamical systems. However, the verification of system properties, such as safety, is based on reachability calculations, which are the sources of insurmountable complexity. This talk addresses indirect verification methods, which are based on abstracting the dynamical systems by models of reduced complexity and preserving central properties of the original systems.","PeriodicalId":360438,"journal":{"name":"HAS","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126574832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Sampling-based Decentralized Monitoring for Networked Embedded Systems","authors":"E. Bartocci","doi":"10.4204/EPTCS.124.9","DOIUrl":"https://doi.org/10.4204/EPTCS.124.9","url":null,"abstract":"Decentralized monitoring (DM) refers to a monitoring technique, where each component must infer,based on a set of partial observations if the global property is satisfied. Our work is inspired by thetheoretical results presented by Baurer and Falcone at FM 2012 [7], where the authors introducedan algorithm for distributing and monitoring LTL formulae, such that satisfaction or violation ofspecifications can be detected by local monitors alone. However, their work is based on the mainassumption that neither the computation nor communication take time, hence it does not take intoaccount how to set a sampling time among the components such that their local traces are consistent.In this work we provide a timed model in UPPAAL and we show a case study on a networkedembedded systems board.","PeriodicalId":360438,"journal":{"name":"HAS","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132120687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"World Automata: a compositional approach to model implicit communication in hierarchical Hybrid Systems","authors":"M. Capiluppi, R. Segala","doi":"10.4204/EPTCS.124.7","DOIUrl":"https://doi.org/10.4204/EPTCS.124.7","url":null,"abstract":"We propose an extension of Hybrid I/O Automata (HIOAs) to model agent systems and their implicit communication through perturbation of the environment, like localization of objects or radio signals diffusion and detection. The new object, called World Automaton (WA), is built in such a way to preserve as much as possible of the compositional properties of HIOAs and its underlying theory. From the formal point of view we enrich classical HIOAs with a set of world variables whose values are functions both of time and space. World variables are treated similarly to local variables of HIOAs, except in parallel composition, where the perturbations produced by world variables are summed. In such way, we obtain a structure able to model both agents and environments, thus inducing a hierarchy in the model and leading to the introduction of a new operator. Indeed this operator, called inplacement, is needed to represent the possibility of an object (WA) of living inside another object/environment (WA).","PeriodicalId":360438,"journal":{"name":"HAS","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130091959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Networked Embedded Control Systems: from Modelling to Implementation","authors":"M. D. Benedetto, G. Pola","doi":"10.4204/EPTCS.124.3","DOIUrl":"https://doi.org/10.4204/EPTCS.124.3","url":null,"abstract":"Networked Embedded Control Systems are distributed control systems where the communication among plants, sensors, actuators and controllers occurs in a shared network. They have been the subject of intensive study in the last few years. In this paper we survey our contribution to this research topic.","PeriodicalId":360438,"journal":{"name":"HAS","volume":"684 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123051068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Monitoring with uncertainty","authors":"E. Bartocci, R. Grosu","doi":"10.4204/EPTCS.124.1","DOIUrl":"https://doi.org/10.4204/EPTCS.124.1","url":null,"abstract":"We discuss the problem of runtime verification of an instrumented program that misses to emit and to monitor some events. These gaps can occur when a monitoring overhead control mechanism is introduced to disable the monitor of an application with real-time constraints. We show how to use statistical models to learn the application behavior and to \"fill in\" the introduced gaps. Finally, we present and discuss some techniques developed in the last three years to estimate the probability that a property of interest is violated in the presence of an incomplete trace.","PeriodicalId":360438,"journal":{"name":"HAS","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121977508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Approximated Symbolic Computations over Hybrid Automata","authors":"A. Casagrande, T. Dreossi, C. Piazza","doi":"10.4204/EPTCS.124.6","DOIUrl":"https://doi.org/10.4204/EPTCS.124.6","url":null,"abstract":"Hybrid automata are a natural framework for modeling and analyzing systems which exhibit a mixed discrete continuous behaviour. However, the standard operational semantics defined over such models implicitly assume perfect knowledge of the real systems and infinite precision measurements. Such assumptions are not only unrealistic, but often lead to the construction of misleading models. For these reasons we believe that it is necessary to introduce more flexible semantics able to manage with noise, partial information, and finite precision instruments. In particular, in this paper we integrate in a single framework based on approximated semantics different over and under-approximation techniques for hybrid automata. Our framework allows to both compare, mix, and generalize such techniques obtaining different approximated reachability algorithms.","PeriodicalId":360438,"journal":{"name":"HAS","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129326237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Completeness of Lyapunov Abstraction","authors":"R. Wisniewski, Christoffer Sloth","doi":"10.4204/EPTCS.124.5","DOIUrl":"https://doi.org/10.4204/EPTCS.124.5","url":null,"abstract":"In this work, we continue our study on discrete abstractions of dynamical systems. To this end, we use a family of partitioning functions to generate an abstraction. The intersection of sub-level sets of the partitioning functions defines cells, which are regarded as discrete objects. The union of cells makes up the state space of the dynamical systems. Our construction gives rise to a combinatorial object - a timed automaton. We examine sound and complete abstractions. An abstraction is said to be sound when the flow of the time automata covers the flow lines of the dynamical systems. If the dynamics of the dynamical system and the time automaton are equivalent, the abstraction is complete. \u0000The commonly accepted paradigm for partitioning functions is that they ought to be transversal to the studied vector field. We show that there is no complete partitioning with transversal functions, even for particular dynamical systems whose critical sets are isolated critical points. Therefore, we allow the directional derivative along the vector field to be non-positive in this work. This considerably complicates the abstraction technique. For understanding dynamical systems, it is vital to study stable and unstable manifolds and their intersections. These objects appear naturally in this work. Indeed, we show that for an abstraction to be complete, the set of critical points of an abstraction function shall contain either the stable or unstable manifold of the dynamical system.","PeriodicalId":360438,"journal":{"name":"HAS","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129432460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}