Diagnosability and opacity are two well-studied problems in discrete-event systems. We revisit these two problems with respect to expressiveness and complexity issues. We first relate different notions of diagnosability and opacity. We consider in particular fairness issues and extend the definition of Germanos et al. [ACM TECS, 2015] of weakly fair diagnosability for safe Petri nets to general...

The analysis of opaque relations presents a problem to classic Optimality Theory (OT) (Prince and Smolensky 1993, McCarthy and Prince 1993), inherently a surface-oriented theory. Many different proposals have been made to integrate the analysis of opacity into OT. In this paper, we address the problem of opacity in Tundra Nenets (TN), a Uralic (Samoyedic) language spoken in Arctic Russia and No...

The opacity property characterises the absence of confidential information flow towards inquisitive attackers. Verifying opacity is well established for finite automata but is known to be not decidable for more expressive models like Turing machines or Petri nets. As a consequence, for a system dealing with confidential information, formally certifying its confidentiality may be impossible, but...

statement of problem: esthetic materials undergo some physical and mechanical changes, during their service in oral cavity. purpose: the aim of this study was the evaluation of the color and opacity stability of ideal makoo (idm) composites and compare it with tetric ceram. material and methods: fifteen disk shaped samples of each material was divided into three groups of five. different aging ...

purpose : the aim of this study was to determine indications of keratoplasty during 7 years (1999–2006) in emam-rreza and vali-asr teaching hospitals of birjand university of medical sciences. methods : medical records of all patients who underwent penetrating keratoplasty (pk) in teaching hospitals of birjand university of medical sciences from 1999 to 2006 were investigated retrospectively. t...

We evaluate the logarithmic derivative of the depth of the solar convective zone with respect to the logarithm of the radiative opacity, ∂ lnRCZ/∂ lnκ. We use this expression to show that the radiative opacity near the base of the solar convective zone (CZ) must be known to an accuracy of±0.6% in order to calculate the CZ depth to the accuracy of the helioseismological measurement, RCZ = (0.713...

We study the complexity of deciding whether a modular discrete event system is detectable (resp. opaque, A-diagnosable). Detectability arises in the state estimation of discrete event systems, opacity is related to the privacy and security analysis, and A-diagnosability appears in the fault diagnosis of stochastic discrete event systems. Previously, deciding weak detectability (opacity, A-diagn...

This study explores the implications of portfolio opacity for the design of asset management contracts. This is a case of particular interest given the growing importance of ‘alternative’ assets like hedge funds and private equity funds in institutional portfolios. The alternative assets are often characterized by relatively illiquid or non-publicly traded holdings, proprietary strategies, and ...