scholarly journals PARAMETRIC VERIFICATION AND TEST COVERAGE FOR HYBRID AUTOMATA USING THE INVERSE METHOD

2013 ◽  
Vol 24 (02) ◽  
pp. 233-249 ◽  
Author(s):  
LAURENT FRIBOURG ◽  
ULRICH KÜHNE
Keyword(s):  
Hybrid Systems ◽  
Hybrid System ◽  
Inverse Method ◽  
Timed Automata ◽  
Test Coverage ◽  
Hybrid Automata ◽  
System Verification

Hybrid systems combine continuous and discrete behavior. Hybrid Automata are a powerful formalism for the modeling and verification of such systems. A common problem in hybrid system verification is the good parameters problem, which consists in identifying a set of parameter valuations which guarantee a certain behavior of a system. Recently, a method has been presented for attacking this problem for Timed Automata. In this paper, we show the extension of this methodology for hybrid automata with linear and affine dynamics. The method is demonstrated with a hybrid system benchmark from the literature.

Bayesian hybrid automata: Reconciling formal methods with metrology

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Paul Kröger ◽  
Martin Fränzle
Keyword(s):  
System Dynamics ◽  
Hybrid Systems ◽  
Hybrid System ◽  
Formal Model ◽  
Continuous Control ◽  
Hybrid Automata ◽  
Physical Processes ◽  
Natural Domain ◽  
State Tracking ◽  
Smart Technologies

Abstract Hybrid system dynamics arises when discrete actions meet continuous behaviour due to physical processes and continuous control. A natural domain of such systems are emerging smart technologies which add elements of intelligence, co-operation, and adaptivity to physical entities. Various flavours of hybrid automata have been suggested as a means to formally analyse dynamics of such systems. In this article, we present our current work on a revised formal model that is able to represent state tracking and estimation in hybrid systems and thereby enhancing precision of verification verdicts.

scholarly journals Hybrid Automata: An Algorithmic Approach Behavioral Hybrid Systems

2019 ◽  
Vol 6 (2) ◽  
pp. 83-90
Author(s):  
Koteswara Rao Ballamudi
Keyword(s):  
Hybrid Systems ◽  
Brain Research ◽  
Timed Automata ◽  
Point Of View ◽  
Hybrid Automata ◽  
Test Bed ◽  
Algorithmic Approach ◽  
Security Properties ◽  
The Right ◽  
Time Systems

Hybrid automata strategies have advanced as a vital tool to design, check and direct the execution of hybrid systems. Any way they can – and we assume should – be utilized to communicate quantitative models about hybrid systems in different areas, for example, experimental sciences. Since the conventional design of hybrid automata compares well to consecutively integrate behavioral chains in living creatures, we look for a use of hybrid modeling procedures in the social sciences and, particularly, brain research. We attempt to address the question related to how human drivers move onto an expressway and simultaneously utilize this study as our test-bed for utilizing hybrid automata inside behavioral sciences. Hybrid automata give a language to displaying and exploring advanced and simple calculations in real-time systems. Hybrid automata are studied here from a dynamical systems point of view. Essential and adequate conditions for the presence and uniqueness of arrangements are inferred and a class of hybrid automata whose arrangements rely consistently upon the underlying state is described. The outcomes on presence, uniqueness, and progression fill in as a beginning stage for solid study. In this paper, we present the structure of hybrid automata as a model and detailed language for hybrid systems. Hybrid automata can be seen as a theory of timed automata, in which the behavior of factors is represented in each state by a bunch of differential conditions. We show that a large number of the models considered in the workshop can be characterized by hybrid automata. While the reachability issue is undecidable in any event, for extremely confined classes of hybrid automata, we present two semi-decision techniques for checking security properties of piecewise-straight hybrid automata, in which all factors change at steady rates. The two techniques are based, individually, on limiting and figuring fix points on for the most part endless state spaces. We show that if the end of the method, at that point they offer the right responses. We then show that for a significant number of the run of the mill workshop models, the strategies do end and hence give an algorithmic approach to confirming their properties.

scholarly journals Counterexample-Guided Abstraction-Refinement for Hybrid Systems Diagnosability Analysis

10.29007/t8n3 ◽  
2018 ◽  
Author(s):  
Hadi Zaatiti ◽  
Lina Ye ◽  
Philippe Dague ◽  
Jean-Pierre Gallois
Keyword(s):  
Hybrid Systems ◽  
Hybrid System ◽  
Timed Automata ◽  
Discrete Event ◽  
Fault Detection And Isolation ◽  
Time Constraints ◽  
Design Stage ◽  
Qualitative Level ◽  
On Line ◽  
Spurious Effect

Verifying behavioral or safety properties of hybrid systems, either at design stage such as state reachability and diagnosability, or on-line such as fault detection and isolation is a challenging task. We are concerned here with abstractions oriented towards hybrid systems diagnosability checking. The verification can be done on the abstraction by classical methods developed for discrete event systems extended with time constraints, which provide a counterexample in case of non-diagnosability. The absence of such a counterexample proves the diagnosability of the original hybrid system. In the presence of a counterexample, the first step is to check if it is not a spurious effect of the abstraction and actually exists for the hybrid system, witnessing thus non-diagnosability. Otherwise, we show how to refine the abstraction, guided by the elimination of the counterexample, and continue the process of looking for another counterexample until either a final result is obtained or we reach an inconclusive verdict. We make use of qualitative modeling and reasoning to compute discrete abstractions. Abstractions as timed automata are particularly studied as they allow one to handle time constraints that can be captured at a qualitative level from the hybrid system.

Autonomy and Responsibility in Hybrid Systems

2017 ◽  
Author(s):  
Wulf Loh ◽  
Janina Loh
Keyword(s):  
Hybrid Systems ◽  
Hybrid System ◽  
Moral Dilemma ◽  
Autonomous Driving ◽  
Shared Responsibility ◽  
Driving System ◽  
Autonomous Cars ◽  
Self Driving Cars ◽  
Trolley Cases ◽  
Autonomous Driving System

In this chapter, we give a brief overview of the traditional notion of responsibility and introduce a concept of distributed responsibility within a responsibility network of engineers, driver, and autonomous driving system. In order to evaluate this concept, we explore the notion of man–machine hybrid systems with regard to self-driving cars and conclude that the unit comprising the car and the operator/driver consists of such a hybrid system that can assume a shared responsibility different from the responsibility of other actors in the responsibility network. Discussing certain moral dilemma situations that are structured much like trolley cases, we deduce that as long as there is something like a driver in autonomous cars as part of the hybrid system, she will have to bear the responsibility for making the morally relevant decisions that are not covered by traffic rules.

Fuel-Cell Hybrid Systems to Generate Shipboard Electrical Power

2009 ◽  
Author(s):  
W. J. Sembler ◽  
S. Kumar
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Air Quality ◽  
Hybrid Systems ◽  
Hybrid System ◽  
Cell Hybrid ◽  
Electrical Power ◽  
History Of ◽  
Marine Applications ◽  
Fuel Cell Hybrid

The reduction of shipboard airborne emissions has been receiving increased attention due to the desire to improve air quality and reduce the generation of greenhouse gases. The use of a fuel cell could represent an environmentally friendly way for a ship to generate in-port electrical power that would eliminate the need to operate diesel-driven generators or use shore power. This paper includes a brief description of the various types of fuel cells in use today, together with a review of the history of fuel cells in marine applications. In addition, the results of a feasibility study conducted to evaluate the use of a fuel-cell hybrid system to produce shipboard electrical power are presented.

scholarly journals Progress on Powertrain Verification Challenge with C2E2

10.29007/1kq2 ◽  
2018 ◽  
Author(s):  
Chuchu Fan ◽  
Parasara Sridhar Duggirala ◽  
Sayan Mitra ◽  
Mahesh Viswanathan
Keyword(s):  
Rate Of Convergence ◽  
Control Systems ◽  
Hybrid System ◽  
State Machines ◽  
Powertrain Control ◽  
Verification Tool ◽  
Discrepancy Rate ◽  
System Verification ◽  
Made In

In this paper, we present the progress we have made in verifying the benchmark powertrain control systems introduced in the last ARCH workshop. We implemented the algorithm for computing local discrepancy (rate of convergence or divergence of trajectories) reported in the hybrid system verification tool C2E2. We created Stateflow translations of the original models to aid the processing using C2E2 tool. We also had to encode the different driver behaviors in the form of state machines. With these customizations, we have been successful in verifying one of the easier (but still challenging) benchmarks from the powertrain suite. In this paper, we present some of the engineering challenges and describe the artifacts we created in the process.

scholarly journals Optimal Sizing of a Pv-Wind Hybrid System Using Measured and Generated Database

2021 ◽  
Vol 03 (01) ◽  
pp. 34-44
Author(s):  
Abdellah Benallal ◽  
◽  
Nawel Cheggaga ◽  
Keyword(s):  
Renewable Energy ◽  
Wind Speed ◽  
Wind Turbine ◽  
Hybrid Systems ◽  
Hybrid System ◽  
Measured Data ◽  
Electrical Load ◽  
Wind Potential ◽  
Simulation Results ◽  
The Cost

Renewable energy hybrid systems give a good solution in isolated sites, in the Algerian desert; wind and solar potentials are considerably perfect for a combination in a renewable energy hybrid system to satisfy local village electrical load and minimize the storage requirements, which leads to reduce the cost of the installation. For a good sizing, it is essential to know accurately the solar potential of the installation area also wind potential at the same height where wind electric generators will be placed. In this work, we optimize a completely autonomous PV-wind hybrid system and show the techno-economical effects of the height of the wind turbine on the sizing of the hybrid system. We also compare the simulation results obtained from using wind speed measured data at 10 meters and 40 meters of height with the ones obtained from using wind speed extrapolation on HOMER software.

Condition-based opportunistic maintenance policy for a series–parallel hybrid system with economic dependence

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Aiping Jiang ◽  
Zhenni Huang ◽  
Jiahui Xu ◽  
Xuemin Xu
Keyword(s):  
Hybrid Systems ◽  
Hybrid System ◽  
Maintenance Policy ◽  
Economic Dependence ◽  
Opportunistic Maintenance ◽  
Content Type ◽  
Cost Rate ◽  
Parallel Hybrid ◽  
In Series ◽  
Redundant Structure

PurposeThe purpose of this paper is to propose a condition-based opportunistic maintenance policy considering economic dependence for a series–parallel hybrid system with a K-out-of-N redundant structure, where a single component in series is denoted as subsystem1, and K-out-of-N redundant structure is denoted as subsystem2.Design/methodology/approachBased on the theory of Residual Useful Life (RUL), inspection points are determined, and then different maintenance actions are adopted in the purpose of minimizing the cost rate. Both perfect and imperfect maintenance actions are carried out for subsystem1. More significantly, regarding economic dependence, condition-based opportunistic maintenance is designed for the series–parallel hybrid system: preemptive maintenance for subsystem1, and both preemptive and postponed maintenance for subsystem2.FindingsThe sensitivity analysis indicates that the proposed policy outperforms two classical maintenance policies, incurring the lowest total cost rate under the context of both heterogeneous and quasi-homogeneous K-out-of-N subsystems.Practical implicationsThis model can be applied in series–parallel systems with redundant structures that are widely used in power transmission systems in electric power plants, manufacturing systems in textile factories and sewerage systems. Considering inconvenience and high cost incurred in the inspection of hybrid systems, this model helps production managers better maintain these systems.Originality/valueIn maintenance literature, much attention has been received in repairing strategies on hybrid systems with economic dependence considering preemptive maintenance. Limited work has considered postponed maintenance. However, this paper uses both condition-based preemptive and postponed maintenance on the issue of economic dependence bringing opportunities for grouping maintenance activities for a series–parallel hybrid system.

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