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Nouakchott, Mauritania

for the university in Nouakchott see Lebanese International University for the university in Sana'a see Lebanese International University The Lebanese International University is a private university established by the philanthropist and former Lebanese defense and education minister Abdul Rahim Mourad. The language of instruction is English. Wikipedia.

Assi A.,Lebanese International University | Al-Amin M.,Technology Group
Procedia Engineering | Year: 2012

Recently, efforts in improving the efficiency of monocrystalline silicon (c-Si) solar cells are focused on optimizing the emitter profile and the metallization which reduces the recombination losses, the contact resistances and improve the collection probability of carriers. The emitter recombination is reduced with decreasing the well passivated emitter thickness and lowering the doping concentration whereas it increases the metal-semiconductor contact resistance and thus reducing the fill factor (FF). In this paper, the metal-semiconductor ohmic contact formation, the emitter optimization, the co-relation with ohmic contact, and the optimum metallization pattern are investigated. The emitter saturation current density (Joe), the carrier life time (τeff), the internal quantum efficiency (IQE), the series resistance (Rs), the short circuit current (I sc), the open circuit voltage (Voc), the fill factor (FF) and the cell efficiency are analyzed for different emitter profiles and compared with the standard process. A batch of 156 pseudo mm square mono c-Si solar cells with average cell efficiency of17.5% is observed at 72-75 Ω/ sheet resistance. © 2012 Elsevier B.V. Source

Simon E.P.,Lille University of Science and Technology | Ros L.,CNRS GIPSA Laboratory | Hijazi H.,Lebanese International University | Ghogho M.,University of Leeds
IEEE Transactions on Signal Processing | Year: 2012

In this paper, the problem of joint carrier frequency offset (CFO) and channel estimation for OFDM systems over the fast time-varying frequency-selective channel is explored within the framework of the expectation-maximization (EM) algorithm and parametric channel model. Assuming that the path delays are known, a novel iterative pilot-aided algorithm for joint estimation of the multipath Rayleigh channel complex gains (CG) and the carrier frequency offset (CFO) is introduced. Each CG time-variation, within one OFDM symbol, is approximated by a basis expansion model (BEM) representation. An autoregressive (AR) model is built to statistically characterize the variations of the BEM coefficients across the OFDM blocks. In addition to the algorithm, the derivation of the hybrid Cramér-Rao bound (HCRB) for CFO and CGs estimation in our context of very high mobility is provided. We show that the proposed EM has a lower computational complexity than the optimum maximum a posteriori estimator and yet incurs only an insignificant loss in performance. © 2011 IEEE. Source

Mehanna A.,University of Hamburg | Mehanna A.,Lebanese International University | Szpotowicz E.,University of Hamburg | Schachner M.,University of Hamburg | And 4 more authors.
Experimental Neurology | Year: 2014

The immune system plays important functional roles in regeneration after injury to the mammalian central and peripheral nervous systems. After damage to the peripheral nerve several types of immune cells, invade the nerve within hours after the injury. To gain insights into the contribution of T- and B-lymphocytes to recovery from injury we used the mouse femoral nerve injury paradigm. RAG2-/- mice lacking mature T- and B-lymphocytes due to deletion of the recombination activating gene 2 were subjected to resection and surgical reconstruction of the femoral nerve, with the wild-type mice of the same inbred genetic background serving as controls. According to single frame motion analyses, RAG2-/- mice showed better motor recovery in comparison to control mice at four and eight weeks after injury. Retrograde tracing of regrown/sprouted axons of spinal motoneurons showed increased numbers of correctly projecting motoneurons in the lumbar spinal cord of RAG2-/- mice compared with controls. Whereas there was no difference in the motoneuron soma size between genotypes, RAG2-/- mice displayed fewer cholinergic and inhibitory synaptic terminals around somata of spinal motoneurons both prior to and after injury, compared with wild-type mice. Extent of myelination of regrown axons in the motor branch of the femoral nerve measured as g-ratio was more extensive in RAG2-/- than in control mice eight weeks after injury. We conclude that activated T- and B-lymphocytes restrict motor recovery after femoral nerve injury, associated with the increased survival of motoneurons and improved remyelination. © 2014 Elsevier Inc. Source

Habchi C.,Lebanese International University | Antar G.,American University of Beirut
Computers and Fluids | Year: 2015

We present direct numerical simulation results of a conducting fluid subject to the Lorentz force resulting from an external static magnetic field normal to the electric current direction. This research discipline, generally known as electromagnetic forcing flows, is motivated by many engineering and physical applications such as plasma physics, geophysics, weather prediction and solid melting processes. In this paper, a computational fluid dynamics (CFD) code is developed using the open source C++ library OpenFOAM. The solver is based on the electric potential method coupled to the Navier-Stokes equations. The code is then benchmarked to other well-known solvers using different numerical techniques and to the experiment. Excellent agreement is obtained for the forced toroidal channel flow, with three-dimensional dynamics, as well as for the confined vortex-pair in a cylindrical container, with quasi-two-dimensional dynamics. Quasi-two-dimensional forced flow in the presence of non-uniform magnetic field at low Hartmann number is also used for comparison. Furthermore, qualitative comparison with the experiment is made where we are able to successfully simulate the vortex pairs generated by the Lorentz force and the effect of the magnetic field gradient leading to the so-called gradB jets in accordance with the experiment. © 2015 Elsevier Ltd. Source

Elattar E.E.,Lebanese International University
IEEE PES Innovative Smart Grid Technologies Conference Europe | Year: 2011

Wind power prediction is one of the most critical aspects in wind power integration and operation. This paper presents a new approach to a wind power prediction by combining support vector regression (SVR) with a local prediction framework which employs the correlation dimension and mutual information methods used in time-series analysis for data preprocessing. Local prediction makes use of similar historical data patterns in the reconstructed space to train the regression algorithm. To build an effective local SVR method, the parameters of SVR must be selected carefully. Therefore, a new method is proposed in this paper. The proposed method which known as genetic algorithm (GA)-Local SVR searches for SVR's optimal parameters using real value GA. These optimal parameters are then used to construct the local SVR algorithm. The performance of the proposed method (GA-Local SVR) is evaluated with the real world wind power data from England and is compared with the seasonal auto regressive integrated moving average (SARIMA) method and radial basis function (RBF) network. The results show that the proposed method provides a much better prediction performance in comparison with other methods employing the same data. © 2011 IEEE. Source

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