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91.
92.
Noura Beji Bassem Jarboui Mansour Eddaly Habib Chabchoub 《Journal of computational science》2010,1(3):159-167
The Redundancy Allocation Problem generally involves the selection of components with multiple choices and redundancy levels that produce maximum system reliability given various system level constraints as cost and weight. In this paper we investigate the series–parallel redundant reliability problems, when a mixing of components was considered. In this type of problem both the number of redundancy components and the corresponding component reliability in each subsystem are to be decided simultaneously so as to maximise the reliability of system. A hybrid algorithm is based on particle swarm optimization and local search algorithm. In addition, we propose an adaptive penalty function which encourages our algorithm to explore within the feasible region and near feasible region, and discourage search beyond that threshold. The effectiveness of our proposed hybrid PSO algorithm is proved on numerous variations of three different problems and compared to Tabu Search and Multiple Weighted Objectives solutions. 相似文献
93.
M. B. A. Mansour 《Acta Appl Math》2010,109(3):939-947
This paper concerns with the traveling wave solutions of a nonlinear reaction-diffusion-advection model for describing the
spatiotemporal evolution of bacterial colony pattern. We use different methods for computing the traveling wave fronts of
the model equations. One of the methods involves the traveling wave equations. Numerical solutions of these equations as an
initial-value problem lead to accurate computations of the wave profiles and speeds. The second method is to construct the
time-dependent solutions by solving an initial-moving boundary-value problem for the PDE system, showing an approximation
for such wave fronts, in particular, the minimum speed traveling wave. 相似文献
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We study classes of set partitions determined by the avoidance of multiple patterns, applying a natural notion of partition containment that has been introduced by Sagan. We say that two sets S and T of patterns are equivalent if for each n the number of partitions of size n avoiding all the members of S is the same as the number of those that avoid all the members of T. 相似文献
98.
Boubakri L. Al-Ayed Abdullah S. Mansour L. Harrath A. A. Al-Tamimi J. Özdemir I. Yasar S. Hamdi N. 《Transition Metal Chemistry》2019,44(4):321-328
Transition Metal Chemistry - The carbonylative Suzuki cross-coupling of 2-bromopyridine with various boronic acids to prepare unsymmetrical arylpyridine ketones has been carried out using... 相似文献
99.
Ahmed Sameh E. Mansour M. A. Hussein Ahmed Kadhim Mallikarjuna B. Almeshaal Mohammed A. Kolsi Lioua 《Journal of Thermal Analysis and Calorimetry》2019,135(2):1443-1449
Journal of Thermal Analysis and Calorimetry - In the present paper, the performance of the graphene oxide in the solar steam generation has experimentally been examined. For this purpose, a setup... 相似文献
100.
Z. Hadjou Bélaid S. Ben Mansour D. Boroguiaa A. Boubris L. Benhabib F. Z. Benkhaled 《Journal of Macromolecular Science: Physics》2020,59(11):686-696
AbstractThis work examines the development and characterization of tripropylene glycol di-acrylate/liquid crystal E7 (TPGDA/LC E7) PDLCs composite materials (polymer-dispersed-liquid-crystals). These systems were produced by UV irradiation photopolymerization (PIPS) of a mixture of the monomer tripropylene glycol di-acrylate (TPGDA) and the liquid crystal E7 (LC E7, a mixture of three cyano-biphenyl and one cyano-terphenyl LCs), in the presence of 2?wt% (of the acrylate/E7 mixture) of a photoinitiator. Electro-optical, thermal and optical characterization was used to understand the effect of the LC concentration on the electro-optical and thermo-physical properties of these materials. Polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) studies were performed to observe the system morphology and to determine the transition temperatures of these materials, both as a function of their composition. The findings showed a slight variation of the nematic-isotropic transition temperature, TNI, of the LC E7 and of the glass transition temperature, Tg, of the TPGDA polymeric matrix as a function of the mass percentage of the LC E7. A very good electro-optical response for the composition 30/70?wt % TPGDA/LC E7 was obtained. 相似文献