Caractérisation de HgCdTe en couche mince à 10,6 μm

Hg-diffusion in a CdTe substrate leads to a graded index waveguide. M-lines analysis gives the refractive index profile of these guides. From published data giving refractive index versus cadmium concentration, we deduce the concentration profile. Measurement accuracy enables to show a fabrication bending on some samples of 10 μm/5 mm. The propagation of a 10.6 μm wave exhibits an exceptionnally low attenuation (<0.5 dB/cm) on all modes. Up to 10 kW/cm² — cw power density has been guided without damage.     

Automatic identification of music performers with learning ensembles

This article addresses the problem of identifying the most likely music performer, given a set of performances of the same piece by a number of skilled candidate pianists. We propose a set of very simple features for representing stylistic characteristics of a music performer, introducing ‘norm-based’ features that relate to a kind of ‘average’ performance. A database of piano performances of 22 pianists playing two pieces by Frédéric Chopin is used in the presented experiments. Due to the limitations of the training set size and the characteristics of the input features we propose an ensemble of simple classifiers derived by both subsampling the training set and subsampling the input features. Experiments show that the proposed features are able to quantify the differences between music performers. The proposed ensemble can efficiently cope with multi-class music performer recognition under inter-piece conditions, a difficult musical task, displaying a level of accuracy unlikely to be matched by human listeners (under similar conditions).     

Effect of different brining treatments on the fermentation of cv. Conservolea green olives processed by the Spanish-method

The effect of different initial brining conditions on the spontaneous fermentation of cv. Conservolea green olives was studied. The different treatments included: (a) brine acidification with 2 per thousand (v/v) lactic acid (control), (b) addition of 25 per thousand (v/v) 1n HCl (c) substitution of the initial brine by 20% (v/v) with a brine from a previous fermentation (brine re-use). Microbial growth, pH, titratable acidity and organic acids were monitored. Brine re-use process was the most effective in minimizing the likelihood of spoilage since it decreased the survival period of enterobacteria (24 days), followed by the HCl treatment (28 days) and the control (35 days). However, after 35 days of fermentation, pH values reached a plateau above 4.8 in all treatments indicating that supplementary treatments were necessary to enhance lactic acid fermentation and attain acidity/pH levels that would improve the physicochemical characteristics of the final product and ensure its safety. Addition of 1.5% (w/v) glucose in the HCl-treated and brine re-use processes as well as 5 per thousand (v/v) lactic acid in the control was performed. All supplementary treatments were effective in reducing pH to a final value of 4.3-4.5. However, glucose increased the final concentration of lactic acid in brine re-use and HCl-treated processes (73.4 and 67.8 mm, respectively) compared with the control that was lacking in acidity (44.7 mm), denoting a clear advantage of glucose over lactic acid as a supplement.     

Steady-state drifting stabilization of RWD vehicles

A control scheme to stabilize rear-wheel-drive (RWD) vehicles with respect to high-sideslip cornering (drifting) steady-states using coordinated steering and drive torque control inputs is presented in this paper. The choice of coordinated control inputs is motivated by the observed data collected during the execution of drifting maneuvers by an expert driver. In addition, the steering and drive torque input variables directly correlate to a human driver's steering wheel and throttle commands. The control design is based on a comprehensive vehicle model with realistic tire force and drive-train characteristics, and validated in a high-fidelity simulation environment.     

Optimal partitioning for multi-vehicle systems using quadratic performance criteria

We consider the problem of characterizing a generalized Voronoi diagram that is relevant to a special class of area assignment problems for multi-vehicle systems. It is assumed that the motion of each vehicle is described by a second order mechanical system with time-varying linear or affine dynamics. The proposed generalized Voronoi diagram encodes information regarding the proximity relations between the vehicles and arbitrary target points in the plane. These proximity relations are induced by an anisotropic (generalized) distance function that incorporates the vehicle dynamics. In particular, the generalized distance is taken to be the minimum control effort required for the transition of a vehicle to an arbitrary target point with a small terminal speed at a fixed final time. The space we wish to partition corresponds to the union of all the terminal positions that can be attained by each vehicle using finite control effort. Consequently, the partition space has lower dimension than the state space of each vehicle. We show that, in the general case, the solution to the proposed partitioning problem can be associated with a power Voronoi diagram generated by a set of spheres in a five-dimensional Euclidean space for the computation of which efficient techniques exist in the relevant literature.     

Fluid-solids flow with thermal and hydrodynamic non-equilibrium

A model is developed to describe the behaviour of particles in air streams. The equations of particle flow and heat transfer are given in dimensionless form. Two practical applications for suspension flows are solved: (a) the flow past a temperature step and (b) the injection of hot particles in a pipe carrying a gas. In both cases instantaneous velocity and temperature differences for the gas and solids are calculated and the effect of several dimensionless groups (such as Reynolds numbers, loading and dimension ratios) on these two quantities is determined. It was found that non-equilibrium effects are accentuated when bigger particles are in the mixture.     

The anatomic basis of the gracilis perforator flap

Another perforator flap, the gracilis perforator flap, has recently been added to the armamentarium of reconstructive surgeons. A detailed study of the anatomy of this flap was undertaken in this study. Forty-seven dissections were performed in cadavers and clinical cases of gracilis muscle harvesting for various reconstructive reasons. According to our findings, at least one musculocutaneous perforator of large calibre was found in the majority of the dissections performed (87%), emanating from the proximal third of gracilis. All the perforators were located within a radius of 7 cm from the point of entrance of the gracilis main vascular pedicle. In their majority, they emanated proximal to that point (83%) from the middle part (anteroposterior axis) of the muscle (62%). The intramuscular course of the perforators was easily followed and few muscular branches were encountered, before they joined the main vascular pedicle. A sensory branch of the anterior obturator nerve, accompanying the perforators, was occasionally found (29%). Finally, a superficial vein, branch of the greater saphenous, was always found within the skin territory of the flap in all dissections performed in cadavers.     

Greek dry-salted olives: Monitoring the dry-salting process and subsequent physico-chemical and microbiological profile during storage under different packing conditions at 4 and 20 °C

Naturally black olives cv. Thassos were processed in dry salt according to industrial procedure by uniformly dispersing 40 kg of coarse salt in 100 kg freshly harvested olives. Dry-salting process was monitored by measuring selected physico-chemical (weight loss, NaCl content, pH, a_w, reducing sugars) and microbiological parameters (total viable counts, lactic acid bacteria, enterobacteria, yeasts, pseudomonads). Total weight loss amounted to 21 g/100 g after 80 days of dry-salting. Salt content in the fruits increased to 7.4 g/100 g followed by a decrease in water activity from 0.98 to 0.76. The pH did not change significantly presenting a slight decrease from 5.25 to 4.92. The initial microflora of the fruits comprised of lactic acid bacteria (4.1 log₁₀ cfu/g), yeasts (5.7 log₁₀ cfu/g), enterobacteria (3.7 log₁₀ cfu/g ) and pseudomonads (4.0 log₁₀ cfu/g). In the end of dry-salting, no microbial groups were enumerated apart from yeasts, due to the low water activity of the product. After dry-salting, olives were packed in HDPE bags under air (control samples) and 100 ml/100 ml CO₂. Another lot of fruits was dipped in 1 g/100 ml solution of potassium sorbate for 10 min prior to packing in the same bags under aerobic conditions. All packages were stored at 4 and 20 °C for a period of 180 days. During storage, the microbial flora comprised of yeasts, while no lactic acid bacteria, enterobacteria, pseudomonads or Staphylococcus aureus were detected as the low water activity/high salt content does not favour their growth. At 4 °C, the population of yeasts declined steadily throughout storage, but to a different extend depending on the packing treatment. At 20 °C, only potassium sorbate was effective in suppressing yeast growth. All packing treatments prevented fungal growth at both storage temperatures, apart from the samples stored in air. The pH, a_w and salt content did not change significantly throughout storage.     

Ambient intelligence technologies in support of shipping markets’ operations

The Intelligent Maritime Environment (i-MARE) framework and technological platform we introduce in our paper conceptualize an innovative, collaborative and context-aware network business model for cargo shipping. The i-MARE framework considers ambient-intelligence technologies, in particular an ontology-derived and web semantics based interoperability framework and application modules for key shipping process areas, namely the maritime regulations-rules compliance and port operations support. We explain how the improvement of the later operations can be realized in terms of the proposed technological platform towards the effective matching of individual companies’ capabilities and needs with market demands for cargo shipping. Whereas cargo shipping refers to a number of different markets, our framework is generic and adaptable to the requirements of particular sectors, for instance ocean bulk shipping or short sea container shipping. The framework presented is proposed for testing and application in the maritime sector, whereas in our paper we examine, as a proof of concept, short sea shipping business cases and a normative modelling and architectural solution.