A semantic approach to interpolation

Craig interpolation is investigated for various types of formulae. By shifting the focus from syntactic to semantic interpolation, we generate, prove and classify a series of interpolation results for first-order logic. A few of these results non-trivially generalize known interpolation results; all the others are new. We also discuss someapplications of our results to the theory of institutions and of algebraic specifications,and a Craig-Robinson version of these results

Simultaneous cathodoluminescence hyperspectral imaging and X-ray microanalysis

A facility has been developed to acquire hyperspectral cathodoluminescence (CL) images simultaneously with X-ray composition data. Based around an electron microprobe, the system uses a built-in Cassegrain microscope to efficiently couple emitted light directly into the entrance slit of an optical spectrograph. A cooled array detector allows the parallel acquisition of CL spectra, which are then built up into a multidimensional data-cube containing the full set of spectrally- and spatially-resolved information for later analysis. This setup has the advantage of allowing wavelength-dispersive X-ray (WDX) data to be recorded concurrently, providing a powerful technique for the direct comparison of luminescent and compositional properties of materials. The combination of beam and sample scanning thus allows the correlation of composition and luminescence inhomogeneities on length scales ranging from a few cm to sub-micron

Allen Linear (Interval) Temporal Logic --Translation to LTL and Monitor Synthesis--

The relationship between two well established formalisms for temporal reasoning is first investigated, namely between Allen's interval algebra (or Allen's temporal logic, abbreviated \ATL) and linear temporal logic (\LTL). A discrete variant of \ATL is defined, called Allen linear temporal logic (\ALTL), whose models are \omega-sequences of timepoints, like in \LTL. It is shown that any \ALTL formula can be linearly translated into an equivalent \LTL formula, thus enabling the use of \LTL techniques and tools when requirements are expressed in \ALTL. %This translation also implies the NP-completeness of \ATL satisfiability. Then the monitoring problem for \ALTL is discussed, showing that it is NP-complete despite the fact that the similar problem for \LTL is EXPSPACE-complete. An effective monitoring algorithm for \ALTL is given, which has been implemented and experimented with in the context of planning applications

WATER QUALITY INDEX FOR ASSESSMENT OF DRINKING WATER SOURCES FROM MEDIAŞ TOWN, SIBIU COUNTY

The purpose of this study was to evaluate the drinking water sources quality from Mediaş Town, Sibiu County. In November 2013, 6 water samples were taken from different drinking water sources and each water sample was analysed to determinate physico-chemical parameters (using a portable multiparameter WTW 320i major ions (using DIONEX ICS1500 ion chromatograph and heavy metals (using Atomic Absorption Spectrophotometer model ZENIT 700 Analytik Jena). The investigated physico-chemical parameters were: temperature, salinity, electrical conductivity (EC), pH, total dissolved solids (TDS) and redox potential (ORP). The analysed major ions were: lithium (Li+), sodium (Na+), potassium (K+), magnesium (Mg2+), calcium (Ca2+), fluoride( F-), chloride (Cl-), bromide (Br-), nitrite (NO2-), nitrate (NO3-), phosphate (PO43- ) and sulphate (SO42-). The investigated heavy metals were: lead (Pb), zinc (Zn), cooper (Cu), iron (Fe), cadmium (Cd), nickel (Ni), chromium (Cr) and arsenic (As). The Water Quality Index (WQI) was calculated using the analysed water quality parameters and it ranged from 76 (very poor water quality) to 375 (unsuitable for drinking)

Behavioural reasoning for conditional equations

Object-oriented (OO) programming techniques can be applied to equational specification logics by distinguishing visible data from hidden data (that is, by distinguishing the output of methods from the objects to which the methods apply), and then focusing on the behavioural equivalence of hidden data in the sense introduced by H. Reichel in 1984. Equational specification logics structured in this way are called hidden equational logics, HELs. The central problem is how to extend the specification of a given HEL to a specification of behavioural equivalence in a computationally effective way. S. Buss and G. Roşu showed in 2000 that this is not possible in general, but much work has been done on the partial specification of behavioural equivalence for a wide class of HELs. The OO connection suggests the use of coalgebraic methods, and J. Goguen and his collaborators have developed coinductive processes that depend on an appropriate choice of a cobasis, which is a special set of contexts that generates a subset of the behavioural equivalence relation. In this paper the theoretical aspects of coinduction are investigated, specifically its role as a supplement to standard equational logic for determining behavioural equivalence. Various forms of coinduction are explored. A simple characterisation is given of those HELs that are behaviourally specifiable. Those sets of conditional equations that constitute a complete, finite cobasis for a HEL are characterised in terms of the HEL's specification. Behavioural equivalence, in the form of logical equivalence, is also an important concept for single-sorted logics, for example, sentential logics such as the classical propositional logic. The paper is an application of the methods developed through the extensive work that has been done in this area on HELs, and to a broader class of logics that encompasses both sentential logics and HELs. © 2007 Cambridge University Press.FCT via UIM

A minimal core calculus for Solidity contracts

The Ethereum platform supports the decentralized execution of smart contracts, i.e. computer programs that transfer digital assets between users. The most common language used to develop these contracts is Solidity, a Javascript-like language which compiles into EVM bytecode, the language actually executed by Ethereum nodes. While much research has addressed the formalisation of the semantics of EVM bytecode, relatively little attention has been devoted to that of Solidity. In this paper we propose a minimal calculus for Solidity contracts, which extends an imperative core with a single primitive to transfer currency and invoke contract procedures. We build upon this formalisation to give semantics to the Ethereum blockchain. We show our calculus expressive enough to reason about some typical quirks of Solidity, like e.g. re-entrancy.Comment: arXiv admin note: substantial text overlap with arXiv:1905.0436

DC conduction mechanism of some new lower rim substituted calixarenes derivatives in thin films

Date du colloque : 09/2014International audienc

Tourism and the city: the impact on residents' quality of life

The present work investigates the relationship between tourism presence and perceptions of urban quality of life of resident populations (UQOL). Nowadays, this topic is at the forefront since many European cities have started raising their voice against mass tourism. An ad hoc questionnaire was designed and submitted to resident population of two Mediterranean destinations. Following an integrative approach à la Sen, UQOL is analysed using the presence of the services/amenities (capabilities) as well as their accessibility (functionings). Findings indicate that both presence and mainly accessibility of services/amenities matter for UQOL and that a negative effect of tourism prevails

A Homogeneous Actor-Based Monitor Language for Adaptive Behaviour

This paper describes a structured approach to encoding monitors in an actor language. Within a configuration of actors, each of which publishes a history, a monitor is an independent actor that triggers an action based on patterns occurring in the histories. We define a monitor language based on linear temporal logic and show how it can be homogeneously embedded within an actor language. The approach is demonstrated through a number of examples and evaluated in terms of a real-world actor-based simulation