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61.
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
62.
We count derangements, involutions and unimodal elements in the wreath product C
r
≀ S
n
by the numbers of excedances, fixed points and 2-cycles. Properties of the generating functions, including combinatorial
formulas, recurrence relations and real-rootedness are studied. The results obtained specialize to those on the symmetric
group S
n
and on the hyperoctahedral group B
n
when r = 1, 2, respectively. 相似文献
63.
Mansour Mohammadpour Farhad Hosseinzadeh-Lotfi Gholam-Reza Jahanshahloo 《The Journal of the Operational Research Society》2015,66(7):1206-1211
Data envelopment analysis (DEA) is a non-parametric approach based on linear programming that has been widely applied for evaluating the relative efficiency of a set of homogeneous decision-making units (DMUs) with multiple inputs and outputs. The original DEA models use positive input and output variables that are measured on a ratio scale, but these models do not apply to the variables in which negative data can appear. However, with the widespread use of interval scale data and undesirable data, the emphasis has been directed towards the simultaneous consideration of the positive and negative data in DEA models. In this paper, using the slacks-based measure, we propose an extended model to evaluate the efficiency of DMUs, even if some variables are measured on an interval scale and some on a ratio scale. Moreover, the extended model allows for the presence of all interval-scale variables, which are capable of taking both negative and positive values. 相似文献
64.
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
65.
66.
We consider the rate of convergence for a class of perturbed hemivariational inequalities in reflexive Banach Spaces. Our results can be viewed as an extension and refinement of some previous known results in this area. 相似文献
67.
Johannes Hatzl Toufik Mansour Mark Shattuck 《Journal of Mathematical Modelling and Algorithms》2011,10(2):193-203
Consider the set S of points in the plane consisting of the ordered pairs (i, j ), where
1 \leqslant i \leqslant m1 \leqslant i \leqslant m and
1 \leqslant j \leqslant n1 \leqslant j \leqslant n. A problem related to the study of segmentation evaluation of visual images concerns finding a permutation σ of the points of S for which the sum
?s ? Sd(s, s(s)) \sum\limits_{s \in S}d(s, \sigma(s)) 相似文献
68.
Let x and y be two variables satisfying the commutation relation xy=qyx+hf(y), where f(y) is a polynomial. In this paper, using Young diagrams and generating functions techniques, we study the binomial formula
(x+y)
n
and we present an identity for x
m
y. The connection to Operator Calculus is discussed and several special cases are treated explicitly. 相似文献
69.
Toufik Mansour 《Discrete Mathematics》2011,311(16):1778
The chromatic polynomial of a simple graph G with n>0 vertices is a polynomial of degree n, where αk(G) is the number of k-independent partitions of G for all k. The adjoint polynomial of G is defined to be , where is the complement of G. We find explicit formulas for the adjoint polynomials of the bridge–path and bridge–cycle graphs. Consequence, we find the zeros of the adjoint polynomials of several families of graphs. 相似文献
70.
Michael Farnsworth Elhadj Benkhelifa Ashutosh Tiwari Meiling Zhu Mansour Moniri 《Memetic Computing》2011,3(3):175-197
The application of multi objective evolutionary algorithms (MOEA) in the design optimisation of microelectromechanical systems (MEMS) is of particular interest in this research. MOEA is a class of soft computing techniques of biologically inspired stochastic algorithms, which have proved to outperform their conventional counterparts in many design optimisation tasks. MEMS designers can utilise a variety of multi-disciplinary design tools that explore a complex design search space, however, still follow the traditional trial and error approaches. The paper proposes a novel framework, which couples both modelling and analysis tools to the most referenced MOEAs (NSGA-II and MOGA-II). The framework is validated and evaluated through a number of case studies of increasing complexity. The research presented in this paper unprecedentedly attempts to compare the performances of the mentioned algorithms in the application domain. The comparative study shows significant insights into the behaviour of both of the algorithms in the design optimisation of MEMS. The paper provides extended discussions and analysis of the results showing, overall, that MOGA-II outperforms NSGA-II, for the selected case studies. 相似文献
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