Array-OL with delays,a domain specific specification language for multidimensional intensive signal processing

Intensive signal processing applications appear in many application domains such as video processing or detection systems. These applications handle multidimensional data structures (mainly arrays) to deal with the various dimensions of the data (space, time, frequency). A specification language allowing the direct manipulation of these different dimensions with a high level of abstraction is a key to handling the complexity of these applications and to benefit from their massive potential parallelism. The Array-OL specification language is designed to do just that. We introduce here an extension of Array-OL to deal with states or delays by the way of uniform inter-repetition dependences. We show that this specification language is able to express the main patterns of computation of the intensive signal processing domain.     

Real-time control of angioplasty balloon inflation based on feedback from intravascular optical coherence tomography: preliminary study on an artery phantom

A method is proposed to achieve computerized control of angioplasty balloon inflation, based on feedback from intravascular optical coherence tomography (IVOCT). Controlled balloon inflation could benefit clinical applications, cardiovascular research, and medical device industry. The proposed method was experimentally tested for balloon inflation within an artery phantom. During balloon inflation, luminal contour of the phantom was extracted from IVOCT images in real time. Luminal diameter was estimated from the obtained contour and was used in a feedback loop. Based on the estimated actual diameter and a target diameter, a computer controlled a programmable syringe pump to deliver or withdraw liquid in order to achieve the target diameter. The performance of the control method was investigated under different conditions, e.g., various flow rates and various target diameters. The results were satisfactory, as the control method provided convergence to the target diameters in various experiments.     

CHARACTERISATION OF HEAVY CRUDE OILS AND PETROLEUM RESIDUES -REVIEW OF THE RESULTS OBTAINED BY THE ASVAHL ANALYTICAL GROUP

ABSTRACT

The ASVAHL Analytical Group has worked for four years. The main objectives were :

1) To develop straight forward methods suitable for heavy products which allow an effective conversion unit follow-up and a better understanding of the phenomenon involved in. Methods which were studied include global characterizations, elementary and structural analysis.

2) To increase the knowledge of the intimate structure of heavy products. To do that, fundamental research have been done sometimes in collaboration with university laboratories and by the use of a wide range of sophisticated methods (molecular distillation, gas chromatography, mass spectrometry alone or coupled with gas chromatography, ¹H, ¹³C, ³³S nuclear magnetic resonance, FT/infra red, EXAFS/XANES, small angle X-ray and neutron scattering).

In the same way, the ASVAHL Analytical Group has collected a standard sample bank. It organized an internal symposium dedicated for the characterization of heavy products (Lyon, France, 1984).     

Repetitive model refactoring strategy for the design space exploration of intensive signal processing applications

The efficient design of computation intensive multidimensional signal processing applications requires dealing with three kinds of constraints: those implied by the data dependencies, the non-functional requirements (real-time, power consumption) and resources availability of the execution platform. Modeling and Analysis of Real-time and Embedded systems (MARTE) UML profile through its repetitive structure modeling (RSM) package is well suited to model the inherent parallelism within these applications, a compact representation of parallel execution platforms and the distributive mapping of one on another. The execution of such a specification respects the whole set of constraints defined upon, while the quality of the scheduling is directly linked to the quality of the mapping of the multidimensional structures (data arrays or parallel loop nests) into time and space. We propose here a strategy to use a refactoring tool dedicated to this kind of application that allows to find good trade-offs in the usage of storage and computation resources and in parallelism (both task and data parallelism) exploitation. This strategy is illustrated on an industrial radar application.     

Comparative influence of a single allergen exposure on the different components of airway response to methacholine

We compared the effects of an allergen challenge on airway responsiveness to methacholine, the slope of the dose-response curve (DRC) and post-methacholine fall in forced vital capacity (FVC) or forced expiratory volume in 1 s (FEV1)/FVC, and determined whether any changes in these parameters were related to the presence and magnitude of the late asthmatic response (LAR) in mild stable asthma. Twenty-three allergic asthmatic subjects had an allergen challenge, preceded and followed 24 (n = 12) and/or 48 (n = 22) h later by a methacholine challenge. Sixteen subjects had a dual asthmatic response to the allergen. On the post-allergen methacholine challenge, as compared with the pre-allergen test, differences in mean fall in FVC or FEV1/FVC at 20% fall in FEV1 and the slope of the DRC did not achieve statistical significance, even in the group with LAR, which showed a significant increase in airway responsiveness at 24 h. There was, however, a correlation between allergen-induced changes in PC20 and (1) the change in post-methacholine FVC fall in the LAR group at 48 h, and (2) the change in the slope of the DRC in the early-asthmatic-response group at 24 h. In conclusion, allergen-challenge-induced changes in airway response to methacholine are heterogeneous among asthmatic subjects and although it may increase airway responsiveness (PC20), particularly in late responders, it minimally affects the other aspects of airway response to methacholine, suggesting that a more powerful or sustained allergic stimulus is required to modify the latter.     

Substitutional Atom Influence on the Electronic and Transport Properties of Mn4Si7

Mn₄Si₇ has been substituted with the following elements: Cu, Fe, Re and Cr on the Mn site, and Al, B, Ge, Sn, Ga, In, Na and Tl on the Si site. The Seebeck coefficient, electrical conductivity and power factor of the substitutional alloys have been evaluated by using density functional theory calculations, and the temperature dependence of the electronic transport properties has been investigated at different charge carrier concentrations by solving the semi-classical Boltzmann transport equation. We show that the substitution of Cu for Mn worsens the thermoelectric properties, while that with Fe appears the?most efficient for increasing the power factor. For In and Tl substitutions, the Seebeck coefficient is increased due to the high d-states contribution in the density of states at the Fermi level. Although the power factor is limited by a poor electrical conductivity, Mn₃₂Si₅₅Tl could exhibit a good figure of merit provided that the amount of Tl atoms is low (at most 1 at.%) and the charge carrier concentration is not too high (around 10²⁰ cm^?3).     

Introducing the fractional-order Darwinian PSO

One of the most well-known bio-inspired algorithms used in optimization problems is the particle swarm optimization (PSO), which basically consists on a machine-learning technique loosely inspired by birds flocking in search of food. More specifically, it consists of a number of particles that collectively move on the search space in search of the global optimum. The Darwinian particle swarm optimization (DPSO) is an evolutionary algorithm that extends the PSO using natural selection, or survival of the fittest, to enhance the ability to escape from local optima. This paper firstly presents a survey on PSO algorithms mainly focusing on the DPSO. Afterward, a method for controlling the convergence rate of the DPSO using fractional calculus (FC) concepts is proposed. The fractional-order optimization algorithm, denoted as FO-DPSO, is tested using several well-known functions, and the relationship between the fractional-order velocity and the convergence of the algorithm is observed. Moreover, experimental results show that the FO-DPSO significantly outperforms the previously presented FO-PSO.