Analyse tectono-sédimentaire de la serie continentale Eocène du Djebel El-Kohol, près de Brézina (revers sud de l'atlas saharien) Algerire

L'analyse sédimentologique de 1'Eockne continental du Djebe El -Kohol (Brézina, revers sud de 1'Atlas saharien) a permis de mettre en évidence I'origine des dépots. L'interprétation des milieux de sédimentation et leur environnement t~enct ompte de l'analyse séquentielleverticale.Deux zones sont distinctes:d´une part, une zone proximale correspondants aux paléoreliefs du domaine atlasique émergé i la fin du Crétacé et sans cesser rajeunis par des mouvements compressifs et d'autre part, une zone distale s.1. ou zone d'enfoncement et comblement bien illustrée par une sédimentation diversifiée (évaporites, détritiques fins et grossiers) et oh sont observés des phénomknes de transformation par épigénie Les épandages détritiques d'El Koholproviennent essentiellement de l'érosion de 1'Atlas saharien durant la phase compressive intense d'age éockne largement ressentie dans les domaines tello-rifain et pyrénéo-provencal

A new finger inverse kinematics method for an anthropomorphic hand

Proceedings of: 2011 IEEE International Conference on Robotics and Biomimetics (ROBIO), December 7-11, 2011, Phuket (Thailand)In this paper, a new method for solving the inverse kinematics of the fingers of an anthropomorphic hand is proposed. Our approach combines a Modified Selectively Damped Least Squares (MSDLS) and Jacobian Transpose (JT) methods. The main advantages of this method with respect to the ordinary SDLS are: optimal Cartesian increment, shorter computation time and better response near singularity configurations. The original JT method exhibits a strong shattering with small magnitudes which occurs near the goal position or in the case of unreachable positions. Like in the SDLS, a damping factor was applied to each input singular vector to filter the undesirable behavior. A comparative study between the MSDLS applied to the inverse Jacobian and JT matrix is developed to investigate manipulator performance in critical end-point positions of the index finger of a commercial anthropomorphic robotic hand and also to evaluate the impact of the increment length on computation time.European Community's Seventh Framework Progra

Parallel Algorithm for Brain Tissues Segmentation in T1-Weighted MR Images on 3D Reconfigurable Mesh Computer

In this paper, we propose a parallel algorithm for brain tissues segmentation from T1-weighted Magnetic Resonance Images (MRI) on Massively Parallel architecture named reconfigurable mesh computer (MCR), this brain tissues are already extracted using our method named Threshold Morphologic Brain Extraction method (TMBE)[1]. The use of this massively parallel architecture is introduced in order to improve the complexities of the corresponding algorithms. The image of size (M x N x K) to be processed must be stored on the RMC of the same size, one Voxel per Processing Element (PE). The proposed method consists in the brain tissues segmentation using parallel version of the modified fuzzy c-means MFCM [2], named PMFCM. This algorithm is directly applied on the extracted volume. The corresponding parallel program of the proposed algorithm is validated on a 3D Reconfigurable Mesh emulator [3]

Electrochemical oxidation of 2-chloroaniline in single and divided electrochemical flow cells using boron doped diamond anodes

Electrochemical oxidation (EO) using boron-doped diamond (BDD) electrodes attracted increasing interests due to its high efficiency in mineralizing chlorinated organic pollutants in water. However, it produces hazardous disinfection by-products (DBPs) including chloramines, chlorate and perchlorate ions and discharges acidic streams. In this work, an attempt to neutralize the acidic effluent and reduce the production of DBPs was developed. To do that, the EO of 2-chloroaniline (2-CA) in single and divided electrochemical flow cells using BDD anode and stainless steel cathode was investigated. The results showed that complete degradation of 2-CA and high mineralization yields were achieved using single and divided compartment cells. The separation of anolyte and catholyte by anion exchange membrane (AEM) in divided electrochemical configuration enhanced the efficiency of the electrochemical treatment and reduced the energy consumption; while, higher concentrations of free chlorine, nitrate, chlorate, and perchlorate ions were generated in the anolyte. A post-treatment of the treated solution in the cathodic compartment at low current density was effective in reducing the amount of free chlorine and chlorate ions, transferring chloride and nitrate ions to the anodic compartment by electro-dialysis, and neutralizing the anolyte and catholyte. Divided electrochemical cell configuration has the potential to achieve more efficient treatment of 2-CA for the recovery of valuable by-products (which can be considered as a powerful synthetic tool, from an environmental point of view; to produce high-added value products)

Fabrication of Si3n4@si@cu thin films by RF sputtering as high energy anode material for Li-ion batteries

Silicon and silicon nitride (Si3N4 ) are some of the most appealing candidates as anode materials for LIBs (Li-ion battery) due to their favorable characteristics: low cost, abundance of Si, and high theoretical capacity. However, these materials have their own set of challenges that need to be addressed for practical applications. A thin film consisting of silicon nitride-coated silicon on a copper current collector (Si3N4@Si@Cu) has been prepared in this work via RF magnetron sputtering (Radio Frequency magnetron sputtering). The anode material was characterized before and after cycling to assess the difference in appearance and composition using XRD (X-ray Powder Diffraction), XPS (X-ray Photoelectron Spectroscopy), SEM/EDX (Scanning Electron Microscopy/ Energy Dispersive X-Ray Analysis), and TEM (Transmission Electron Microscopy). The effect of the silicon nitride coating on the electrochemical performance of the anode material for LIBs was evaluated against Si@Cu film. It has been found that the Si3N4@Si@Cu anode achieved a higher capacity retention (90%) compared to Si@Cu (20%) after 50 cycles in a half-cell versus Li+/Li, indicating a significant improvement in electrochemical performance. In a full cell, the Si3N4@Si@Cu anode achieved excellent efficiency and acceptable specific capacities, which can be enhanced with further research.Qatar University collaborative grant No. QUCG-CAS-20/21-4. Qatar National Research Fund (QNRF) grant No. for NPRP8-1467-1-26

Estimation des effets de la torsion dans les bâtiments soumis à l'action sismique

Nous proposons d'étudier l'influence des effets de torsion induite sur le comportement d'une structure asymétrique. Deux types de structures sont considérés, une symétrique et une autre asymétrique en termes de masse. Nous utilisons un code d'éléments finis qui a permet d'effectuer des analyses temporelles en dynamique linéaire et non linéaire ainsi que des analyses statique non-linéaire. Les réponses des bâtiments sont comparées en termes de: déplacement maximum au sommet, la ductilité, le facteur de réduction, la réduction de la force en terme de capacité et de la demande

Physical volcanology and emplacement mechanism of the Central Atlantic Magmatic Province (CAMP) lava flows from the Central High Atlas, Morocco

The best preserved and most complete lava flow sequences of the Central Atlantic Magmatic Province (CAMP) in Morocco are exposed in the Central High Atlas and can reach up to 300 m in thickness. Four distinct formations, emplaced in subaerial environments, are classically recognized: the Lower, Intermediate, Upper and Recurrent formations. These formations are separated by paleosoils and sedimentary sequences (mudstones, siltstones, sandstones, limestones), that are in general less than two meter-thick and may exceptionally reach a thickness of 80 m, representing minor periods of volcanic quiescence. CAMP lava flows of the Central High Atlas can be grouped into two main categories: subaerial compound pahoehoe flows and simple flows. The former type is exclusively confined to the Lower and Intermediate Formations, while simple flows occur in the Upper and Recurrent Formations. The dominance of compound flows in the two lowermost units of the CAMP suggests a slow emplacement during successive sustained eruptive episodes. Instead the thick single flows characterizing the Upper and Recurrent units indicate higher effusive rates. Basaltic pillow lavas (always of short lateral extent: 10 to 100 m), showing radial jointing and vitreous rinds, identical to those found in the Western Meseta, are occasionally associated with hyaloclastites in the base of the Intermediate Formation, immediately above clastic sediments, or in the Upper Formation. The occurrence of pillow lavas does not imply a generalized subaqueous environment at the time of the lava emission. Instead, they represent subaerial flows that entered small lakes occupying depressions on the volcanic topography of the Lower and Intermediate Formations. The short lateral extent of the pillow lavas and their constant stratigraphic position, the existence of lava flows with unequivocal subaerial characteristics associated to sediments containing fossilized wood, clearly indicate onshore emplacement.info:eu-repo/semantics/publishedVersio