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Zouk Mosbeh, Lebanon

Notre Dame University – Louaize is a Catholic, independent university in Zouk Mosbeh, Lebanon. Founded in cooperation with Beirut University College in 1978,as the Louaize College for Higher Education . The name was changed to Notre Dame University – Louaize on August 14, 1987 when the President of The Lebanese Republic issued a decree number 4116 granting the right to operate an independent university. NDU is currently ranked 5th in Lebanon according to its presence on the Web by the Webometrics Ranking of World Universities. Wikipedia.

Assaad J.J.,Notre Dame University - Louaize
Construction and Building Materials

Cementitious grouts injected by vacuum pressure techniques are expected to loose part of the free mixing water with direct consequences on fluidity and penetrability. A new set-up was developed to enable simultaneous assessment of water extracted due to vacuuming and real-time viscosity changes occurring over several minutes of time. A slotted four-bladed vane was used to prevent migration of cement particles away from the center and enable the vane to remain in contact with new material during motion. Test results have shown that the extraction of water decreases fluidity (i.e., flow time) and increases viscosity, mostly due to increased internal friction within the solid particles. Grouts prepared with low water-to-cement ratio and containing moderate to high concentrations of viscosity-modifying admixtures yielded adequate water retentivity with minor variations in viscosity. "Injectability boxes" are proposed to simplify product development and predict variations in grout viscosity during vacuuming. © 2014 Elsevier Ltd. All rights reserved. Source

Rahmani S.,University of Quebec | Mendalek N.,Notre Dame University - Louaize | Al-Haddad K.,University of Quebec
IEEE Transactions on Industrial Electronics

This paper presents a nonlinear control technique for a three-phase shunt active power filter (SAPF). The method provides compensation for reactive, unbalanced, and harmonic load current components. A proportionalintegral (PI) control law is derived through linearization of the inherently nonlinear SAPF system model, so that the tasks of current control dynamics and dc capacitor voltage dynamics become decoupled. This decoupling allows us to control the SAPF output currents and the dc bus voltage independently of each other, thereby providing either one of these decoupled subsystems a dynamic response that significantly slower than that of the other. To overcome the drawbacks of the conventional method, a computational control delay compensation method, which delaylessly and accurately generates the SAPF reference currents, is proposed. The first step is to extract the SAPF reference currents from the sensed nonlinear load currents by applying the synchronous reference frame method, where a three-phase diode bridge rectifier with RL load is taken as the nonlinear load, and then, the reference currents are modified, so that the delay will be compensated. The converter, which is controlled by the described control strategy, guarantees balanced overall supply currents, unity displacement power factor, and reduced harmonic load currents in the common coupling point. Various simulation and experimental results demonstrate the high performance of the nonlinear controller. © 2010 IEEE. Source

Hawi N.S.,Notre Dame University - Louaize
Computers in Human Behavior

Internet addiction has been a subject of research since 1996. In step with this trend, this study aims to illuminate Internet addiction in Lebanon based on research evidence. The timing of this study coincides with the growing rate of penetration of Internet service across the country and with current plans to improve this service. This study investigates Internet usage among adolescents, who are the most vulnerable to Internet addiction in the population. Permission to access schools to conduct this research was obtained from the Ministry of Education and Higher Education. A web-based questionnaire was completed by 833 intermediate and secondary students from public and private schools. The questionnaire included items on demographic information and Internet usage and an Arabic version of Young's Internet Addiction Test (YIAT). The results showed that 4.2% of the sample had significant problems. Furthermore, the more problematic Internet use (PIU) was, the less the Internet was used for information and research, and the more it was used for entertainment. PIU is driven by deficiency needs fuelled by the use of interactive applications. The more deficient the need, the greater the obsession with top-notch interactive applications, and the less frequent the usage of non-interactive applications. © 2012 Elsevier Ltd. All rights reserved. Source

Background: The right ventricle (RV) has an essential function in cardiovascular physiology and pathology. Currently, it is gaining an increasing interest given its recognized role in many cardiovascular conditions. However, echocardiographic assessment of the RV in daily practice is frequently based on qualitative estimation, and it has been regarded as a neglected chamber.Objective: We sought to review and discuss the appropriate approach and latest methods of assessment of the RV by echocardiography.Methods: A MEDLINE/Pubmed search was performed, and 55 relevant articles were selected; articles addressing right ventricular assessment by echocardiography, along with the latest recommendations, have been reviewed and discussed.Results: A RV diameter .42 mm at the base and .35 mm at the mid-cavitary level indicates right ventricular dilatation; a longitudinal myocardial velocity (S’) ,9.5 mm/s, a tricuspid annular plane systolic excursion ,17 mm, and a fractional area change ,35% are indices of right ventricular systolic dysfunction. A right ventricular ejection fraction of .45% and an absolute value of global longitudinal strain of .21% reflect normal systolic function. The significance of dp/dt, the right myocardial performance index and isovolumic myocardial acceleration, is also discussed along with the parameters of right ventricular diastolic function. The use of novel echocardiographic approaches, such as three-dimensional echo and speckle tracking imaging, allows practitioners to overcome the challenges encountered with conventional echocardiography.Conclusion: Accurate assessment of the RV by echocardiography yields early detection of cardiac diseases, enhances risk stratification, and allows timely initiation of appropriate therapy. © the authors, publisher and licensee Libertas Academica Limited. Source

Carlberg K.,Stanford University | Bou-Mosleh C.,Notre Dame University - Louaize | Farhat C.,Stanford University
International Journal for Numerical Methods in Engineering

A Petrov-Galerkin projection method is proposed for reducing the dimension of a discrete non-linear static or dynamic computational model in view of enabling its processing in real time. The right reduced-order basis is chosen to be invariant and is constructed using the Proper Orthogonal Decomposition method. The left reduced-order basis is selected to minimize the two-norm of the residual arising at each Newton iteration. Thus, this basis is iteration-dependent, enables capturing of non-linearities, and leads to the globally convergent Gauss-Newton method. To avoid the significant computational cost of assembling the reduced-order operators, the residual and action of the Jacobian on the right reduced-order basis are each approximated by the product of an invariant, large-scale matrix, and an iteration-dependent, smaller one. The invariant matrix is computed using a data compression procedure that meets proposed consistency requirements. The iteration-dependent matrix is computed to enable the least-squares reconstruction of some entries of the approximated quantities. The results obtained for the solution of a turbulent flow problem and several non-linear structural dynamics problems highlight the merit of the proposed consistency requirements. They also demonstrate the potential of this method to significantly reduce the computational cost associated with high-dimensional non-linear models while retaining their accuracy. © 2010 John Wiley & Sons, Ltd. Source

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