Preliminary Data on the Bioturbation Activity of Hediste Diversicolor (Polychaeta, Nereididae) from the Loire Estuary, France

The ragworm Hediste diversicolor (O. F. Müller, 1776) plays a key role in the estuarine water-sediment interface. This scientific project comes under the framework of the International network Nereis Park Experiment gathering 27 laboratories from all over the world. The experiments were carried out concurrently in spring 2007 using a common protocol. In the Loire estuary, the samples were collected in the intertidal zone of the Saint-Nazaire Bridge. During the field experiment, we estimated the surface area of the burrow walls (Sb) value varied from Sb = 0.26 m2.m-2 to 2.18 m2.m-2 (mean Sb = 0.75 m2.m-2), and the pumping rate (Pr) value from Pr = 0.9 l.d-1m-2 to 7.7 l.d-1 m-2 (mean value Pr = 2.7 l.d-1m-2). The density and the biomass of H. diversicolor populations largely controlled the amount of reworked sediment. In the laboratory, we estimated the pseudo-diffusive mixing, Db value varied from Db = 1.2 to 1.6 (mean Db = 1.5). The non-local transport (r) from the upper layers to the bottom of the tubes varied from r = 1 to 7.2 (mean r = 4.3). A positive relationship could be established between Db and the temperature while on the contrary a negative relationship could be established between the Db and biomass. It seems that small individuals are more efficient reworkers than big ones

Impact of the Integration of a STATCOM Controlled by LQG/H2 Regulator in an Energy System

© The Author(s); licensee IIETA, Edmonton, Canada. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY), https://creativecommons.org/licenses/by/4.0/Nowadays, the reactive power consumption is becoming a serious problem for electricity network management. To overcome this problem, several solutions are proposed in the literature. In the present study, the static reactive power compensator (STATCOM) solution is used to keep the network voltage within its rated range. The STATCOM is modeled in the axes of Park reference frame and is driven controlled by a SVPWM strategy. Its control scheme is based on a multivariable Linear Quadratic Gaussian (LQG/H2) controller, which has the advantage of being applied to systems whose condition is not measured. Simulations are performed using the MATLAB/SIMULINK software. Results are presented, compared and discussed.Peer reviewe

Experimental Investigation of Decoupled Discontinuous PWM Strategies in Open-End Winding Induction Motor Supplied by a Common DC-link

© 2023 IEEE. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1109/JESTPE.2023.3258799Currently, open-end winding induction motors fed by a dual inverter (OEWIM-DI) present an innovative approach to enhance the performance of modern electric drive systems, such as electrical vehicles and electric aircraft applications. However, the DI topology requires a proper switching control strategy to enable the OEWIM drive to fully achieve its performance. This work aims to investigate experimentally the impact of different decoupled discontinuous pulsewidth modulation (DDPWM) control strategies on the performance of the OEWIM-DI supplied by a common dc-link. The criteria performances adopted in this study are: 1) the total harmonic distortion (THD) of the current and voltage; 2) the zero sequence voltage (ZSV); 3) the common mode voltage (CMV); and 4) the DI losses. The various DDPWM control schemes for the 1.5-kW OEWIM-DI motor drive are implemented on a dSPACE 1104 board, and the results are compared with the popular and widely used space-vector PWM (SVPWM) strategy. From the results, it can be concluded that the optimized DDPWM technique gives the best performance. This technique has reduced the CMV by one level and reduces the losses by 50% while having the same THD and ZSV obtained with the SVPWM technique.Peer reviewe

Exploitation of somaclonal variability for the search of saline-tolerant potato (Solanum Tuberosum L.)

The present investigation was conducted with an aim to study the effect of salt stress (NaCl) on in vitro potato callus growth and the potential for exploiting this technique in improving salinity tolerance in potato. The results in the four varieties in the culture medium showed a decrease in all studied parameters like callus growth, relative average growth, water content and salinity sensitivity coefficient upon increasing the salinity of the medium in calluses. It has also been observed that the type of callus has a large effect on the above-mentioned parameters in which better callus growth adapted to 150 mmol NaCl is obtained than unsuitable calli in the same culture medium

Intelligent Health Monitoring of Machine Bearings Based on Feature Extraction

This document is the Accepted Manuscript of the following article: Mohammed Chalouli, Nasr-eddine Berrached, and Mouloud Denai, ‘Intelligent Health Monitoring of Machine Bearings Based on Feature Extraction’, Journal of Failure Analysis and Prevention, Vol. 17 (5): 1053-1066, October 2017. Under embargo. Embargo end date: 31 August 2018. The final publication is available at Springer via DOI: https://doi.org/10.1007/s11668-017-0343-y.Finding reliable condition monitoring solutions for large-scale complex systems is currently a major challenge in industrial research. Since fault diagnosis is directly related to the features of a system, there have been many research studies aimed to develop methods for the selection of the relevant features. Moreover, there are no universal features for a particular application domain such as machine diagnosis. For example, in machine bearing fault diagnosis, these features are often selected by an expert or based on previous experience. Thus, for each bearing machine type, the relevant features must be selected. This paper attempts to solve the problem of relevant features identification by building an automatic fault diagnosis process based on relevant feature selection using a data-driven approach. The proposed approach starts with the extraction of the time-domain features from the input signals. Then, a feature reduction algorithm based on cross-correlation filter is applied to reduce the time and cost of the processing. Unsupervised learning mechanism using K-means++ selects the relevant fault features based on the squared Euclidian distance between different health states. Finally, the selected features are used as inputs to a self-organizing map producing our health indicator. The proposed method is tested on roller bearing benchmark datasets.Peer reviewe

Preliminary investigation of the antimicrobial and mechanisms of resistance of Enterobacteria isolated from minced meat in the Northeast of Algeria: The case of butchers from Constantine

peer-reviewedFood products of animal origin such as fresh meat are easily contaminated by microorganisms if handling, processing and storage conditions are not fully respected. The present study aimed first to evaluate the bacterial load and microbial contamination rates of ground raw beef to identify the main pathogenic flora that dominate and second, to determine the resistance patterns and extended-spectrum beta-lactamase (ESBL) of isolated Gram-negative strains against certain families of antibiotics. Therefore, 39 samples have been collected from 5 butcher shops located in Constantine province in the North-East of Algeria. The samples were analysed for total bacterial count, presence of total and faecal coliforms, Staphylococci and Salmonella. Furthermore, 23 antibiotics were tested using the diffusion method on Mueller-Hinton agar, towards 22 strains isolates. Bacterial analyses showed a high contamination by total aerobic bacteria, total and faecal coliforms. Escherichia coli, Citrobacter spp., Enterobacter spp., Hafnia alvei, Salmonella pullorum and Staphylococcus spp (except Staphylococcus aureus) were further revealed in some samples. The results of the antibiogram test exhibit multi-resistance to more than eight antibiotics with varied effects. From the whole tested strains isolates, the fully susceptibility effect was for spectinomycin (SPT). This study reveals that the analysed minced meat was found to be highly contaminated with antibiotic resistant bacteria. This study allows concluding that appropriate use of antibiotics in compliance with good hygiene practices is essential to reduce the antibiotic resistance identified in this preliminary study

Devenir du nitrite dans les produits carnes: reaction du nitrite avec les acides gras insatures

SIGLEINIST T 75009 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Numerical study of the melting and resolidification of the substrate during the impact of a ceramic droplet in a plasma spraying process

The substrate melting can significantly improve the properties of plasma spray coatings. Indeed the adhesion of the projected particles to the substrate can be ameliorated by the substrate melting. In this article, a numerical model is developed to study the dynamics of fluids and heat transfer with liquid/solid phase change during impact of a fully melted alumina particle on an aluminum solid substrate, taking into account of the substrate melting. The model is based on solving the Navier-Stokes and energy equations with liquid / solid phase change. These equations are coupled with the fluid of volume method (VOF), to follow the free surface of the particle during its spreading and solidification. The finite volume method is used to discretize the equations in a 2D axisymmetric domain. A comparison with the published experimental results was carried out to validate this numerical model. Simulations were performed for different initial droplet diameters to study its effect on droplet spreading as well as on substrate melting. It has been observed that the substrate melting begins before the droplet spreads completely; the substrate melting reaches its maximum when the droplet is close to its total solidification. Droplet spreading and substrate melting are more important for large sizes droplets

Reinforced confidence in self-training for a semi-supervised medical data classification

International audienc