BEval: A Plug-in to Extend Atelier B with Current Verification Technologies

This paper presents BEval, an extension of Atelier B to improve automation in the verification activities in the B method or Event-B. It combines a tool for managing and verifying software projects (Atelier B) and a model checker/animator (ProB) so that the verification conditions generated in the former are evaluated with the latter. In our experiments, the two main verification strategies (manual and automatic) showed significant improvement as ProB's evaluator proves complementary to Atelier B built-in provers. We conducted experiments with the B model of a micro-controller instruction set; several verification conditions, that we were not able to discharge automatically or manually with AtelierB's provers, were automatically verified using BEval.Comment: In Proceedings LAFM 2013, arXiv:1401.056

Nova Eruptions with Infrared Interferometric Observations

Infrared interferometric observations have a great deal of potential to unravel the nature of the nova eruptions. We suggest that techniques, already in place, to derive the ejection details at optical wavelengths be used with infrared interferometric observations to derive parameters such as the ejected mass in a nova eruption. This is achievable based on modelling the initial phase of the eruption when the infrared light is dominated by the free-free thermal process.Comment: To appear in the proceedings of "Physics of Evolved Stars 2015 - A conference dedicated to the memory of Olivier Chesneau

A programme to determine the exact interior of any connected digital picture

Region filling is one of the most important and fundamental operations in computer graphics and image processing. Many filling algorithms and their implementations are based on the Euclidean geometry, which are then translated into computational models moving carelessly from the continuous to the finite discrete space of the computer. The consequences of this approach is that most implementations fail when tested for challenging degenerate and nearly degenerate regions. We present a correct integer-only procedure that works for all connected digital pictures. It finds all possible interior points, which are then displayed and stored in a locating matrix. Namely, we present a filling and locating procedure that can be used in computer graphics and image processing applications

Complex order control for improved loop-shaping in precision positioning

This paper presents a complex order filter developed and subsequently integrated into a PID-based controller design. The nonlinear filter is designed with reset elements to have describing function based frequency response similar to that of a linear (practically non-implementable) complex order filter. This allows for a design which has a negative gain slope and a corresponding positive phase slope as desired from a loop-shaping controller-design perspective. This approach enables improvement in precision tracking without compromising the bandwidth or stability requirements. The proposed designs are tested on a planar precision positioning stage and performance compared with PID and other state-of-the-art reset based controllers to showcase the advantages of this filter

Excimer laser treatment of ZE41 magnesium alloy for corrosion resistance and microhardness improvement

We would like to acknowledge the financial support of the ‘‘Conseil regional de PACA’’ and Protection des Metaux d’Arenc). The authors are grateful to PMA’s engineers Ms. E. Castellan, Ms. A. Gonthier and Mr. F. Miretti for their help and assistance with the salt-spray testsA laser surface melting treatment (LSMT) was performed on a ZE41 Mg-alloy using an excimer KrF laser. The laser-melted layer depth depends on the laser scan speed. The morphology and the microstructure of the laser-melted surface were characterized, thanks to the scanning electron microscopy (SEM). The melted Mg-alloy presented a homogenous distribution of the alloying elements in the magnesium matrix. The laser surface melting treatment increased the microhardness of the ZE41 Mg-alloy and improved its corrosion resistance

The Alcobaça Abbey hydraulic landscape

Introduction: This paper concerns the main domain (“coutos”) of Alcobaça Abbey (central Portugal), founded in 1153. It shows the involvement of the Cistercian monks in shaping hydraulic landscapes along time. This monastic territory is limited westwards by the Atlantic ocean with a cliff coast indented by two large gulfs, the Pederneira lagoon, north , totally sanded up nowadays, and the Alfeizerão lagoon, south, of which only the São Martinho bay still exists. These landscapes have been consolidated along with the monks’ intervention in the hydrographic plan, particularly through a network of canals, the types of which can be summarized as follows: - canals for water conveyance and evacuation, to and from the abbey buildings; - canals related with water-powered engines as grain-, oil-, saw- and fulling-mills, forges and other industrial devices; - canals consequent to the diversion of rivers and streams with two main purposes: . to drain the fields in order to improve the marshes for agricultural use; . to irrigate cultures. Method: The hydraulic landscape planning has been identified and characterized through documentary research, stereoscopic interpretation of panchromatic and infrared “false colour” vertical aerial photographs, and land surveys. Findings / discussion: Flood control seems to have been one of the main hydro technical concern of the Cistercians. Their strategy was to subdivide some hydrographic basins, so that the fields would not be flooded. This was observed in the fields of the ancient Pederneira lagoon, for which an important cartography is available. But the same strategy was probably applied in the Alfeizerão fields. Besides the canals which were analyzed, other canal networks existed but it has not been possible to identify them till now because of the soil erosion or the topographic transformations together with the documental lack of knowledge. The more blatant situation concerns the old Valdeventos monastic farm, at the eastern limit of the “coutos”, where was found a large water storage structure, a tank, presumably to supply an irrigation canal network. Conclusion: Between the early 12th century and the mid 18th century, the Cistercian monks of the Alcobaça Abbey conceived and set in their “coutos” a hydraulic landscape composed by a network of canals with different purposes, and other water devices. This waterscape presents a high heritage value and deserves to be protected and developed.UID/HIS/00057/2013 (POCI-01-0145-FEDER-007702

Reflections on the causes and consequences of the lack of international cooperation during the interwar period : Lessons from the past?

Insufficient international cooperation is usually believed to have disturbed the evolution of the world economy during the interwar period and helped to transform the Roaring Twenties into the Great Depression. The main sections of this paper are devoted to a discussion of the interrelationship between international cooperation, war debts and reparations, international conflicts and political regimes during the interwar period, seeking to develop some hypotheses as to why international cooperation displayed such an irregular performance in that period. Such an evolution should provide us with some warnings about the various dangers that the world in general, and Europe in particular, face today. These are discussed in the conclusion to this paper.info:eu-repo/semantics/publishedVersio