Checking RTECTL properties of STSs via SMT-based Bounded Model Checking

We present an SMT-based bounded model checking (BMC) method for Simply-Timed Systems (STSs) and for the existential fragment of the Real-time Computation Tree Logic. We implemented the SMT-based BMC algorithm and compared it with the SAT-based BMC method for the same systems and the same property language on several benchmarks for STSs. For the SAT- based BMC we used the PicoSAT solver and for the SMT-based BMC we used the Z3 solver. The experimental results show that the SMT-based BMC performs quite well and is, in fact, sometimes significantly faster than the tested SAT-based BMC

Checking WECTLK Properties of TRWISs via SMT-based Bounded Model Checking

In this paper, we present a Satisfiability Modulo Theory based (SMT-based) bounded model checking (BMC) method for Timed Real-Weighted Interpreted Systems and for the existential fragment of the Weighted Epistemic Computation Tree Logic. SMT-based bounded model checking consists in translating the existential model checking problem for a modal logic and for a model to the satisfiability problem of a quantifier-free first-order formula. We have implemented the SMT-BMC method and performed the BMC algorithm on Timed Weighted Generic Pipeline Paradigm benchmark. The preliminary experimental results demonstrate the feasibility of the method. To perform the experiments, we used the state of the art SMT-solver Z3

A Formal Model of an Argumentative Dialogue in the Management of Emotions

In this research, we focus on designing an interactive tool which will be used as an aid in learning how to manage emotions during argumentative dialogues. To this end, a collection of examples illustrating the typical human’s reactions was collated and used to explain mechanisms that appear in dialogues. We present a theoretical background of the project, i.e., a formal system to represent the change of intensity of emotions in argumentative dialogues. We rely here on persuasive dialogue games. A formal language for expressing properties of protocols for dialogues with emotional reasoning is proposed. We suggest that awareness of emotions improves communication between parents and children, and that it is an important element of both raising communication skills in adults and development of communication skills in children

Solder joint failures under thermo-mechanical loading conditions – a review

Solder joints play a critical role in electronic devices by providing electrical, mechanical and thermal interconnections. These miniature joints are also the weakest links in an electronic device. Under severe thermal and mechanical loadings, solder joints could fail in ‘tensile fracture’ due to stress overloading, ‘fatigue failure’ because of the application of cyclical stress and ‘creep failure’ due to a permanent long-term load. This paper reviews the literature on solder joint failures under thermo-mechanical loading conditions, with a particular emphasis on fatigue and creep failures. Literature reviews mainly focused on commonly used lead-free Sn-Ag-Cu (SAC) solders. Based on the literature in experimental and simulation studies on solder joints, it was found that fatigue failures are widely induced by accelerated thermal cycling (ATC). During ATC, the mismatch in coefficients of thermal expansion (CTE) between different elements of electronics assembly contributes significantly to induce thermal stresses on solder joints. The fatigue life of solder joints is predicted based on phenomenological fatigue models that utilise materials properties as inputs. A comparative study of 14 different fatigue life prediction models is presented with their relative advantages, scope and limitations. Creep failures in solder joints, on the other hand, are commonly induced through isothermal ageing. A critical review of various creep models is presented. Many of these strain rate-based creep models are routed to a very well-known Anand Model of inelastic strain rate. Finally, the paper outlined the combined effect of creep and fatigue on solder joint failure.N/

Bounded Model Checking for Metric Temporal Logic Properties of Timed Automata with Digital Clocks

Metric temporal logic (MTL) is a popular real-time extension of linear temporal logic (LTL). This paper presents a new simple SAT-based bounded model-checking (SAT-BMC) method for MTL interpreted over discrete infinite timed models generated by discrete timed automata with digital clocks. We show a new translation of the existential part of MTL to the existential part of linear temporal logic with a new set of atomic propositions and present the details of the new translation. We compare the new method’s advantages to the old method based on a translation of the hard reset LTL (HLTL). Our method does not need new clocks or new transitions. It uses only one path and requires a smaller number of propositional variables and clauses than the HLTL-based method. We also implemented the new method, and as a case study, we applied the technique to analyze several systems. We support the theoretical description with the experimental results demonstrating the method’s efficiency

Checking RTECTL properties of STSs via SMT-based Bounded Model Checking

We present an SMT-based bounded model checking (BMC) method for Simply-Timed Systems (STSs) and for the existential fragment of the Real-time Computation Tree Logic. We implemented the SMT-based BMC algorithm and compared it with the SAT-based BMC method for the same systems and the same property language on several benchmarks for STSs. For the SAT- based BMC we used the PicoSAT solver and for the SMT-based BMC we used the Z3 solver. The experimental results show that the SMT-based BMC performs quite well and is, in fact, sometimes significantly faster than the tested SAT-based BMC

Sposób informacji. Teoria krytyczna Marka Postera

The aim of this paper is to present the main ideas of Mark Poster – an important member of Critical Theory Institute (University of California, Irvine). His theoretical work concerns contemporary French philosophy, Marxism, and media theory. Poster introduces the concept of the “mode of information” as a continuation and development of critical theory. The mode of information is rooted in Foucault’s thought, especially in the very term of discourse. Including analyses of electronical communication, it allows describing social field as a super-panopticon. According to Poster, the mode of information can be an important device to research such problems like family, leisure, work or politics

A Boolean encoding of arithmetic operations

In this paper we present algorithms for a Boolean encoding of four basic arithmetic operations on integer numbers: addition, subtraction, multiplication and division. Integer numbers are encoded in two's complement system as vectors of Boolean formulae, and arithmetic operations are faithfully encoded as operations on vectors of Boolean formulae

Verifying RTECTL properties of a train controller systems

In the paper we deal with a classic concurrency problem - a faulty train controller system (FTC). In particular, we formalize it by means of finite automata, and consider several properties of the problem, which can be expressed as formulae of a soft real-time branching time temporal logic, called RTECTL. Further, we verify the RTECTL properties of FTC by means of SAT-based bounded model checking (BMC) method, and present the performance evaluation of the BMC method with respect to the considered problem. The performance evaluation is given by means of the running time and the memory used