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Ar^+/Ar, O_2^+/O_2 and N_2^+/N_2 Elastic Momentum Collision Cross Sections: Calculation and Validation Using the Semi-Classical Model

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Plasma Science and Technology 2014年第6期16卷 588-592页

作者： djilali BENYOUCEF Mohammed YOUSFI Laboratoire génie electrique et Energies Renouvelables Chlef University Universitéde Toulouse LAPLACE UMR CNRS

The aim of this paper is to obtain relevant sets of collision cross sections of the parent ions in low pressure discharges in argon, oxygen, and nitrogen, i.e., Ar＋ in Ar, O2＋ in O2 and N2＋ in N2. These ion data are first discussed and then validated from comparisons between the calculated transport coefficients and those measured in the literature. The elastic momentum transfer collision cross sections are determined from a semi-classical approximation for the phase shift calculation based on a 12-6-4 inter-particle potential while ion transport coefficients are determined versus the reduced electric field from Monte Carlo simulations.

关键词： inter-particle interaction potentials phase shift JWKB (Jeffreys WentzelKramers Brillouin) momentum collision cross sections Monte Carlo simulation ion trans-port coefficient

Variable range hopping conduction in n-CdSe samples at very low temperature

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Journal of Semiconductors 2015年第12期36卷 14-17页

作者： M Errai A El Kaaouachi H El Idrissi Physics department Ibn Zohr University Faculty of Sciences Laboratoire Electronique électrotechnique Automatique et Traitement de l'Information Département Génie ElectriqueFaculté des Sciences et Techniques de Mohammedia Université Hassan Ⅱ Mohammedia Casablanca

We reanalyzed experimental data already published in Friedman J R, Zhang Y, dai P, et al. Phys Rev B, 1996, 53（15）： 9528. Variable range hopping （VRH） conduction in the insulating three-dimensional n-CdSe samples has been studied over the entire temperature range from 0.03 to 1 K. In the absence of a magnetic field, the low temperature conductivity a of the three samples （A, B and C） obeys the Mott VRH conduction with an appropriate temperature dependence in the prefactor （a = σ0 exp [- （T0/T）]^p with p ≈ 0.25）. This behavior can be explained by a VRH model where the transport occurs by hopping between localized states in the vicinity of the Fermi level, EF, without creation of the Coulomb gap （Cg）. On the contrary, no Efros-Shklovskii VRH is observed, suggesting that the density is constant in the vicinity of the EF.

关键词： n-CdSe samples low temperature variable range hopping density of state

A Multiresolution Channel decomposition for H.264/AVC Unequal Error Protection

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Journal of Signal and Information Processing 2012年第1期3卷 1-15页

作者： Rachid Abbadi Jamal El Abbadi département génie electrique Ecole Mohammadia des Ingenieurs Rabat Morocco.

The most commonly used transmission channel in nowadays provides the same level of protection for all the information symbols. As the level of protection should be adequate to the importance of the information set, it is justified to use UEP channels in order to protect information of variable importance. Multiresolution channel decomposition has emerged as a strong concept and when combined with H.264/AVC layered multiresolution source it leads to outstanding results especially for mobile TV applications. Our approach is a double multiresolution scheme with embedded constellation modulations on its baseband channels followed by OFdM time/frequency multiresolution passband modulation. The aim is to protect The NAL units carrying the most valuable information by the coarse constellations into coarse sub-channels, and the NAL units that contain residual data by fined constellations and transposed into the fined OFdM sub-channels. In the multiresolution protection coding, our approach is a multiresolution decomposition of the core convolutional constituent of the PCCC where the NAL units carrying the most valuable information are coded by the rugged coefficient of the multiresolution code and the NAL units that contains residual data are coded by refined less secure coding coefficients.

关键词： Multiresolution H264.AVC UEP PCCC Turbo Code

double Peak derived from Piezoelectric Coefficient Nonlinearity and Proposal for Self-Powered Systems

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第1期35卷 109-115页

作者： Zhang Bin Li dezhi Li Yingrui ducharne Benjamin gao Jun School of Mechanical Electrical & InformationShandong University School of Mechatronics Engineering Harbin Institute of Technology Laboratoire de génie electrique et Ferroélectricité(LgEF) INSA de Lyon

With the development of wireless sensor network(WSN)applications in intelligent monitoring,additional support for the low power consumption wireless nodes can be provided by piezoceramics that harvest vibrational ***,we describe the effects of stimulation variations on piezoceramics and the energy harvesting circuit *** types of piezoceramics were stimulated at different frequencies and amplitudes to obtain the power output ***,the energy harvesting circuit was studied and coupled with the piezoceramics.A double peak phenomenon was found in energy harvesting using a hard piezoceramic which gave a direct proof that the nonlinearity of the piezo constant should be considered in ***,energy storage and output were studied and *** components for the WSN were recommended according to the output power and the *** results will give an instruction for piezoceramic energy harvesting under various stress amplitudes on its implementation.

关键词： piezoelectric energy harvesting self-powered system energy harvesting circuit output optimization

Electrical properties of ^(70)ge:ga near the metal–insulator transition

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Journal of Semiconductors 2015年第6期36卷 1-5页

作者： M Errai A El kaaouachi H El idrissi Laboratoire MSTI Ecole Supérieure de tecchnologie d'Agadir B.P: 33/S University Ibn ZohrFaculty of Sciences AgadirMorocco Laboratoire Electronique électrotechnique Automatique et Traitement de l'Information Département Génie Electrique Faculté des Sciences et Techniques de Mohammedia Université Hassan II Mohammedia CasablancaBP 146 Quartier YasminaMohammedia

The results of the metal-insulator transition （MIT） induced by impurity concentration are presented in the case of metallic and insulating samples 70ge：ga p-type. The eight samples studied have ga concentrations N ranging from 1.848 × 1017 to 1.912 × 10^17 cm-3. The conductivity measurements were carried out at low temperature in the range 1 to 0.019 K. We provide physical explanations to explain the behaviors of the temperature dependence of the electrical conductivity in both sides of the MIT. The data are for a 70ge：ga sample prepared and reported by Itoh et aL in Ref. [Itoh K M, Watanabe M, Ootuka Y, et al. J Phys Soc Jpn, 2004, 73（1）： 173].

关键词： 70ge: ga semiconductor low temperature impurity concentration metal-insulator variable rangehopping conductivity transport properties

Analytical Calculation of the Energy in a Permanent Magnet

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Journal of Modern Physics 2016年第16期7卷 2281-2287页

作者： Jean-Paul Yonnet Christian Chillet Hicham Allag Lotfi Chouikhi Laboratoire de génie electrique de grenoble G2E Lab Université Grenoble Alpes Grenoble France Laboratoire de génie electrique de grenoble G2E Lab CNRS Grenoble France Laboratoire d’Electronique et d’Electrotechnique Industrielle Jijel University Jijel Algeria

The energy in permanent magnet is not a trivial problem because it exist two types of energy: the field energy and the demagnetizing energy. For parallelepiped shape, the magnet energy has been calculated by fully analytical expressions in 3d. The result has been obtained after four successive integrations of Arctangent and Logarithm functions. The analytically calculated energy corresponds to the demagnetization energy in the magnet. The analytical results have been compared with different terms of energy obtained by computation.

关键词： Analytical Calculation Energy Permanent Magnet

Schottky photodiode using submicron thick diamond epilayer for flame sensing

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Nano-Micro Letters 2009年第1期1卷 30-33页

作者： Y.Koide M.Y.Liao J.Alvarez M.Imura K.Sueishi F.Yoshifusa Sensor Materials Center (SenMC) National Institute for Materials Science (NIMS) Laboratoire de génie electrique de Paris (UMR 8507 CNRS) Ecole Supérieure d’Electricité Universités Paris VI et Paris XI International Center for Materials Nanoarchitectonics (MANA) National Institute for Materials Science (NIMS) ANTEC Co.

The sensing of a flame can be performed by using wide-bandgap semiconductors, which offer a high signal-to-noise ratio since they only response the ultraviolet emission in the flame. diamond is a robust semiconductor with a wide-bandgap of 5.5 e V, exhibiting an intrinsic solar-blindness for deep-ultraviolet(dUV) detection. In this work, by using a submicron thick boron-doped diamond epilayer grown on a type-Ib diamond substrate, a Schottky photodiode device structure- based flame sensor is demonstrated. The photodiode exhibits extremely low dark current in both forward and reverse modes due to the holes depletion in the epilayer. The photodiode has a photoconductivity gain larger than 100 and a threshold wavelength of 330 nm in the forward bias mode. CO and OH emission bands with wavelengths shorter than 330 nm in a flame light are detected at a forward voltage of-10 V. An alcohol lamp flame in the distance of 250 mm is directly detected without a focusing lens of flame light.

关键词： Flame sensing Boron-doped diamond Schottky photodiode

Local model networks based mixed-sensitivity H-infinity control of CE-150 helicopters

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Control Theory and Technology 2017年第1期15卷 34-44页

作者： Mohamed Redouane KAFI Hicham CHAOUI Suruz MIAH Abderrazak dEBILOU Laboratoire de g~nie electrique (LAgE) Universite Kasdi Merbah Ouargla Ouargla Algeria Center for Manufacturing Research Department of ECE Tennessee Technological University Cookeville TN U.S.A. department of Electrical and Computer Engineering Bradley University Peoria IL U.S.A. Faculty of Sciences Department of Electronics Biskra University Algeria

In this paper, a local model network H-infinity control is proposed for CE-150 helicopter stabilization. The proposed strategy capitalizes on recent developments on H-infinity control and its promising results in robust stabilization of plants under unstructured uncertainties. CE-150 helicopters are known for their varying operating conditions along with external disturbances. Therefore, local model networks are introduced for their adaptive feature and since they provide a powerful combination of fuzzy logic and conventional linear control techniques to control nonlinear systems without the added computational burden of soft-computing techniques. Using the fact that the system can be linearized at different operating points, a mixed sensitivity H-infinity controller is designed for the linearized system, and combined within a network to make transitions between them. The proposed control structure ensures robustness, decoupling of the system dynamics while achieving good performance. A comparison is carried-out against the well-known proportional-integral-derivative （PId） control technique. Results are presented to illustrate the controller＇s performance in various operating conditions.

关键词： H-infinity control helicopter local model network robust stabilization

A High dynamic Range gMI Current Sensor

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Journal of Sensor Technology 2012年第4期2卷 165-171页

作者： Aktham Asfour Jean-Paul Yonnet Manel Zidi Laboratoire de génie electrique de grenoble (g2E-Lab) Institut Polytechnique de Grenoble ENSE3 Saint Martin d’Hères France

The design and performances of a high dynamic range dC-AC current sensor utilizing giant Magneto-Impedance (gMI) are presented. The sensor is based on a gMI element with negative feedback. The sensing element is a 30 μm diameter gMI Co-based amorphous wire. It is curled to a toroidal core of 2 cm diameter. A bias magnetic field of about 650 A/m is applied to the gMI element to obtain an asymmetric gMI effect. A strong negative feedback is introduced to ensure linearity in a wide dynamic range. Analog conditioning electronics was fully developed. This includes a square wave oscillator based on an inverter trigger;a peak detector and a high gain amplifier with zero adjust. The gMI element is driven at a 3 MHz frequency and 5 mA peak-to-peak current. The closed-loop operations are investigated and the performances of the sensor are presented. dC current measurements are performed. The sensor exhibits good sensitivity and very good linearity, free from hysteresis, in a wide dynamic range of ±40 A. The sensitivity is about 0.24 V/A and the linearity error is about 0.02% of the full scale (FS). The hysteresis error is smaller than the measurement accuracy. AC current measurements using the developed sensor have also been successfully achieved. The sensor bandwidth in closed-loop was about 1.7 kHz.

关键词： gMI Current Sensor Negative Feedback dC-AC Current Measurements