Analyses et mesures du rayonnement Électromagnétique engendré par des communications haut débit transmises sur des lignes d’énergie

Use of Power Lines Communication for purpose such as Internet access or in-home applications seems to be a very attractive way, however, the problem of conducted and radiated electromagnetic emissions due to these new systems is quite set. The risk of disturbing the Radio communications is, at all, critical in the so-called Short Waves band, from 1 MHz to 30 MHz, allowed to PLC. This paper is aimed in analysing the phenomena that rise to these radiated electromagnetic emissions. We focus especially the analysis to the characterisation of magnetic field by means of simple physical concepts. The experimental and theoretical investigations involve usual power lines owning different dimension and complexity. A large part of this paper is devoted to physical interpretations of the measurement results, underlining the correlation between the magnetic field emission and the common and differential modes currents driven through the line, as well as the connection with the geometrical parameters of the line and with the connected loads. Finally, we present an approach that allows the assessment of the power deliverable by PLC. devices in accordance with the requirements of the harmonised standard EN55022 dealing with conducted emission on the power network.     

Annual Rainfall Forecasting Using Hybrid Artificial Intelligence Model: Integration of Multilayer Perceptron with Whale Optimization Algorithm

Water Resources Management - Rainfall, as one of the key components of hydrological cycle, plays an undeniable role for accurate modelling of other hydrological components. Therefore, a precise...     

Expressions approchées aux basses et aux hautes fréquences des tensions induites de mode commun aux extrémités d’une ligne blindée soumise à une injection ponctuelle de courant

With reference to a preceding paper, this paper allows, in a first step, to determine, at low and high frequencies, approached expressions of the induced common mode voltages at the extremities of a shielded line influenced by a punctual current injection along the shield. These expressions are established for the case of a helicoidal screen with four different schemes of earth connections at the extremities. In a second step, the correction function, i.e. the ratio between the exact and approached solution, and the limit of validity of this latter at high frequencies are addressed.     

Influence of sandwinds on the durability of polyethylene greenhouse aged under sub-saharan climatic conditions

Sandwinds have been simulated with an apparatus developed in our laboratory. Infra red and UV visible spectroscopies, contact angle and interferential microscopy investigations have been performed on untreated polyethylene film sample and on samples submitted at 40 °C to a simulated sandwind for times up to 4 hours. The surface roughness is modified, leading to drastic decrease of the ultra-violet visible light transmission. This phenomenon is due to the presence of small sand particles inlaid in the sample surface and due to surface erosion. In the time range of our experiments, no chemical action due to the sandwind is observed. Electronic Publication     

Multifocal bone tuberculosis: apropos of a case

OBJECTIVE: To review recent experience of gastroschisis at the Royal Children's Hospital, Melbourne. METHODOLOGY: Retrospective review of admissions over a 13 year period, June 1980-June 1993 inclusive, including an analysis of those factors influencing mortality, morbidity and complications. RESULTS: There were 49 infants, of whom two died (4%), both having an associated bowel atresia. Mode of delivery, age at operative repair, birthweight centile and silo repair had no significant effect on the duration of total parenteral nutrition (TPN) or hospital stay. The presence of short gut and/or gut resection and localized bowel narrowing or bowel atresia resulted in a significant increase in the duration of TPN and hospital stay. The presence of a central venous line was a highly significant risk factor for the development of systemic sepsis. CONCLUSION: Currently gastroschisis has a good outlook with a low mortality. Infants with short gut/resection and bowel atresia have a long duration of TPN and hospitalization, with significant morbidity and complications.     

Self-organizing multi-modeling: A different way to design intelligent predictors

Identification of nonlinear systems is an important task for a large number of areas dealing with real-world applications and requirements. Recently, multiple works proposed “multi-model” based approaches to model nonlinear systems. Contrary to the conventional point of view, we propose to deem the multi-modeling as building a modular architecture, inspired from Artificial Neural Networks operation mode, where each neuron (module), represented by one of the local models, realizes some higher level transfer function. This article, deals with generalization of this new multi-modeling concept in the frame of nonlinear system's behavior identification and prediction context. Several multi-model construction strategies and identifiers issued architectures are presented and discussed. Experimental results validating presented multi-model based identifiers have been reported and discussed.     

Hybrid Adaptive Neuro-Fuzzy Models for Water Quality Index Estimation

Soft computing models are known as an efficient tool for modelling temporal and spatial variation of surface water quality variables and particularly in rivers. These model’s performance relies on how effective their simulation processes are accomplished. Fuzzy logic approach is one of the authoritative intelligent model in solving complex problems that deal with uncertainty and vagueness data. River water quality nature is involved with high stochasticity and redundancy due to the its correlation with several hydrological and environmental aspects. Yet, the fuzzy logic theory can give robust solution for modelling river water quality problem. In addition, this approach likewise can be coordinated with an expert system framework for giving reliable and trustful information for decision makers in enhancing river system sustainability and factual strategies. In this research, different hybrid intelligence models based on adaptive neuro-fuzzy inference system (ANFIS) integrated with fuzzy c-means data clustering (FCM), grid partition (GP) and subtractive clustering (SC) models are used in modelling river water quality index (WQI). Monthly measurement records belong to Selangor River located in Malaysia were selected to build the predictive models. The modelling process was included several water quality terms counting physical, chemical and biological variables whereas WQI was the target variable. At the first stage of the research, statistical analysis for each water quality parameter was analyzed toward the WQI. Whereas in the second stage, the predictive models were established. The finding of the current research provides an authorized soft computing model to determine WQI that can be used instead of the conventional procedure that consumes time, cost, efforts and sometimes computation errors.