A new semantics of Propositional Dynamic Logic (PDL) is given in terms of predicate transformers: Instead of associating the standard state transformer with each program, we model programs by operations on sets of states, operations which map postconditions to weakest liberal preconditions. This yields a logic more general than PDL since new program operations such as angelic choice become expr...

This paper adds support for mutually recursive procedures on top of a predicate transformer semantics of imperative programs with pointers implemented in PVS theorem prover. We define and prove correct a collection of mutually recursive procedures which constructs the parsing tree of an expression generated by a context free grammar. We use separation logic to specify and verify these procedure...

Rapid growth of machine learning methodologies and their applications offer new opportunity for improved transformer asset management. Accordingly, power system operators are currently looking for data-driven methods to make better-informed decisions in terms of network management. In this paper, machine learning and data fusion techniques are integrated to estimate transformer loss of life. Us...

An analysis of a dual active bridge (DAB) converter under soft-switching mode in the whole operating range is presented in this paper. A detailed study of the impact of the transformer magnetizing inductance, LM , and snubber capacitance, Cxx, parameters on the soft-switching regions is carried out to obtain some design considerations. Simulation and experimental results which validate the theo...

On-line monitoring of electric power transformers can provide a clear indication of their status and ageing behavior. This paper proposes neural modeling and the local statistical approach to fault diagnosis for the detection of incipient faults in power transformers. The method can detect transformer failures at their early stages and consequently can deter critical conditions for the power gr...

This paper deals with three types of power transformer failure analysis tests which can help in monitoring the transformer condition. The three methods are Conventional oil test, Furan derivatives test and Markov models criteria. Conventional oil testing procedure includes determination of gas concentrations in the transformer oil sample and analyzing the fault by considering ratio of two suita...

We present an implementation of symbolic reachability analysis with the features of compositionality, and intermittent abstraction, in the sense of pefrorming approximation only at selected program points, if at all. The key advantages of compositionality are well known, while those of intermittent abstraction are that the abstract domain required to ensure convergence of the algorithm can be m...

In this paper, we investigate the asymptotic complexity of various predicate abstraction problems relative to the asymptotic complexity of checking an annotated program in a given assertion logic. Unlike previous approaches, we pose the predicate abstraction problem as a decision problem, instead of the traditional inference problem. For assertion logics closed under weakest (liberal) precondit...

We show that the idea of predicates on heap objects can be cast in the framework of predicate abstraction. This leads to an alternative view on the underlying concepts of three-valued shape analysis by Sagiv, Reps and Wilhelm. Our construction of the abstract post operator is analogous to the corresponding construction for classical predicate abstraction, except that predicates over objects on ...

This paper propose an accurate Fuzzy model for describing dynamic hysteresis of ferromagnetic material from measured data using soft computing approaches. We highlighted a fuzzy dynamic model based on measured and normalized input/output data on a C core transformer made of 0.33mm laminations of cold rolled SiFe. Membership’s functions of fuzzy rules are obtained by using the Expectation-Maximi...