Algèbre de processus et synchronisation

We introduce here a calculus of processes, involving an asynchronous parallel composition and some synchronization primitives. It is shown that, in this calculus, many synchronization mechanisms can be formulated; in fact, this calculus is equivalent to Milner's synchronous calculus (1980, 1983). We evaluate its expressive power by means of languages of behaviours.     

Advanced backside failure analysis in 65 nm CMOS technology

Due to reducing size of elementary devices, increasing number of metallization levels and decreasing of power supply voltage, the debug and failure analysis of advanced CMOS designs requires the implementation of specific backside sample preparation methodologies and backside measurement flow.This paper describes the diagnosis and backside failure analysis flow implemented to successfully debug a flip-flop cell designed in 65 nm CMOS technology.     

Fault measurement detection in an urban water supply network

For the improvement of the performance of technical processes, faults and abnormal system operation must be detected and identified. For that purpose different approaches for fault detection have been developed and, here, a model-based approach is used. A diagnosis strategy based on fuzzy residual analysis is presented in this paper. The proposed approach uses the analytical redundancy to detect and isolate faults on sensors. After a presentation of its principle, the method is applied to an urban water supply network. Thanks to the use of fuzzy concept, the suggested diagnosis procedure enables to take into account all the available data and knowledge. Moreover, its efficiency has been proved by using experimental data. Therefore, a supervision software has been developed on the basis of this fuzzy-based fault isolation method.     

Fault detection of broken rotor bars in induction motor using a global fault index

Induction motors play a very important part in the safe and efficient running of any industrial plant. Early detection of abnormalities in the motor would help to avoid costly breakdowns. Accordingly, this work presents a technique for the diagnosis of broken rotor bars in induction motor. Stator voltage and current in an induction motor were measured and employed for computation of the input power of one stator phase. Waveforms of the instantaneous power and line current were subsequently analyzed using the Bartlett periodogram. Different global fault indexes on the instantaneous power spectrum and on the line current spectrum for the fault detection are evaluated. Several rotor cage faults of increasing severity were studied with various load effects. Experimental results prove the efficiency of the employed method.     

Spatially uniform colors for projectors and tiled displays

Abstract— A major issue when setting up multi‐projector tiled displays is the spatial non‐uniformity of the color throughout the display's area. Indeed, the chromatic properties do not only vary between two different projectors, but also between different spatial locations inside the displaying area of one single projector. A new method for calibrating the colors of a tiled display is presented. An iterative algorithm to construct a correction table which makes the luminance uniform over the projected area of one single projector is presented first. This so‐called intra‐projector calibration uses a standard camera as a luminance measuring device and can be processed in parallel for all projectors. Once the color inside each projector is spatially uniform, the set of displayable colors — the color gamut — of each projector is measured. On the basis of these measurements, the goal of the inter‐projector calibration is to find an optimal gamut shared by all the projectors. Finding the optimal color gamut displayable by n projectors in time O(n) is shown, and the color conversion from one specific color gamut to the common global gamut is derived. The method of testing it on a tiled display consisting of 48 projectors with large chrominance shifts was experimentally validated.     

Atmospheric particulate matter (PM) estimation from SeaWiFS imagery

Air quality monitoring by satellite imagery is a potential complementary tool to in-situ measurements. Deriving particulate matter (PM) from the satellite derived aerosol optical thickness (AOT) is not straightforward. The relation between the two quantities is not explicit or, if so, too many unknowns exist. The idea, proposed by Pelletier et al. [Pelletier, B., Santer, R., & Vidot, J. (in press). Retrieving of particulate matter from optical measurements: A semiparametric approach. Journal of Geophysical Research, 112. doi:10.1029/2005JD006737], is to involve in the associations PM-AOT auxiliary meteorological information using a statistical approach. We use this method first on optical ground measurements and second on SeaWiFS imagery in the framework of a regional European project. A SeaWiFS archive was processed both over land and over ocean to produce AOT. A database was developed to associate locally and daily SeaWiFS AOT and PM. A part of this database was used to train the statistical method; another part of it was used for validation. Results are promising. Overall, the method allows retrieving the PM10 with a coefficient of determination of 0.42 and the PM2.5 with a coefficient of determination of 0.48. The outputs of this work are PM10 SeaWiFS maps and a limited comparison with in-situ data is reported.     

Optimising Gas Quenching Technology through Modelling of Heat Transfer

AMONG the carburising and quenching technologieslow-pressure carburising in line with high pressure gasquenching knows a strong development[1],[2],[3].Thisprocess offers indeed an environmentally-friendlyalternative to standard atmosphere carburisingassociated to oil quenching.Gas quenching allows toeliminate parts washing and oil residues processingsteps.Besides low pressure carburising and quenchingprocesses allow more automation of the processFinally gas quenching offers process controopp…     

Time‐domain imaging system in the terahertz range for immovable cultural heritage materials

In the field of cultural heritage science, the use of non‐destructive and contact‐free techniques has increased sharply over the past 10 years. Compared with conventional spectroscopic and imaging techniques such as X‐ray, ultraviolet, infrared, and laser spectroscopy, terahertz time‐domain imaging (THz‐TDI) is an innovative, non‐invasive, and safe technique, which provides good penetration depth (~1 cm) and broad spectral bandwidth (0.1–10 THz). This paper sets out the protocol and methodology for the application of THz‐TDI to immovable cultural heritage, illustrated by a series of case studies. The case studies demonstrate the efficacy of the technique in providing structural and material information for conservators.     

Nanodiamond‐Palladium Core–Shell Organohybrid Synthesis: A Mild Vapor‐Phase Procedure Enabling Nanolayering Metal onto Functionalized sp3‐Carbon

A novel approach for the bottom‐up construction of hybrid organic–inorganic nanocomposites with an intimate arrangement between sp³‐carbon 3D molecular‐size nanodiamonds (diamondoids) and a coated palladium surface as nanolayer is reported. The construction process is conducted stepwisely from the gas phase, using first controlled vapor‐phase self‐assembly of tailor‐made functionalized diamantane derivatives, followed by low‐temperature (45 °C) chemical vapor deposition of an organometallic complex in a reducing H₂ atmosphere over the self‐assembled diamondoid scaffold. The use of self‐assemblies of primary diamantane phosphine and phosphine oxide, which are produced with high structural uniformity and reproducibility, yields new hybrid diamondoid‐palladium materials incorporating Pd? O? PH? diamantane bonding motifs. Additional investigations provide evidence for a very challenging issue in the intimate construction of sp³‐C/metal scaffolds. Scanning electron microscopy and transmission electron microscopy microscopies combined with X‐ray photoelectron spectroscopy surface analysis and EDX bulk analysis confirm the formation of diamondoid‐palladium organohybrids with unique surface layering. The vapor phase‐controlled mild synthetic process allows excellent control over nanocomposite formation and morphology from molecular‐level modifications. As such, this bottom‐up composite building process bridges scales from the molecular (functionalized diamondoids) over nanoscopic (self‐assemblies) to microscopic regime (hybrids), in the challenging association of transition metals with an electronically saturated sp³‐carbon organic host material.