Hayet ML.
New Algorithm for the IV Characteristic Modeling of the Photovoltaic Generator Malfunction within Impedance and Reversed Polarity Faults.; 2015 pp. pp. 506-512.
AbstractIn this paper, we proposed a new methodology that can improved and developed the faults detection and diagnosis methods of the photovoltaic generator, especially when it subjected to the impedance and reversed polarity defects. This proposed algorithm is based on the mathematical modeling of the IV characteristic, of the faulty photovoltaic generator hierarchies as: cell, cells group, module, string and the entire generator, when they submitted to one or more of: cells, bypass and blocking diodes in impedance and reversed polarity faults. This new methodology can facilitated the study of the faulty generator characteristics, and obtained a database for the learning phase and the classification of the new observations collected on the system during its operation. NOMENCLATURE I_phi = Photo-Current. N_Cells = Cells Number in Each Group. N_Groups = Groups Number in Each Module. N_Modules = Modules Number in Each String. N_Strings = Strings Number in the Generator. V_Cell_Imp = Cell Voltage Imposed. I_Cells = Cell Current. V_Cells = Cell Voltage. I_PV = Generator Current. V_PV = Generator Voltage. R_S = Cell Series Resistance. R_SH = Cell Shunt Resistance. I_S1 = Reverse Saturation Current of 1 st Diode. I_S2 = Reverse Saturation Current of 2 nd Diode. m1 = Ideality Factors of 1 st Diode. m2 = Ideality Factors of 2 nd Diode.
Djamel B.
Optimal Planning of Nurses’ Redeployment at Patient Overflow, ISSN / ISBN 978-94-62520-74-5 / 2352-538X.; 2015.
AbstractIn order to provide to his patients a quality medical service at lower cost, the General Administration Department of a University Hospital wants to maintain the number of the allocated nurses as low as possible while guaranteeing a satisfying level of health care. The nurses’ redeployment is an optimization problem that falls under the category of integer linear programming problems whose graphical model is a digraph. The mathematical model is composed of an objective function of several interdependent variables to be obtained and some equality and side constraints that the General Administration Department should not violate in order to achieve satisfaction. The solution of this kind of problems rests on the use of an iterative method known as the simplex algorithm.
Abdessemed R, Tomachvitch V.
Phénomènes Transitoires dans les Machines Electriques.; 2015.
AbstractLa maîtrise des phénomènes physiques ayant lieu lors des processus transitoires dans les machines électriques, l’évaluation qualitative des variations des courants, des tensions, des couples, la prédiction de la conduite de la machine dans de tels régimes comme la perte ou l’augmentation brusque de charge, le fonctionnement en régime asynchrone des machines synchrones, etc…, sont nécessaires pour une conception rationnelle et fiable des machines électriques pouvant supporter des situations d’avarie quelque soit le régime de fonctionnement.