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151.
B. Ivorra A. M. Ramos B. Mohammadi 《Journal of Optimization Theory and Applications》2007,135(3):549-561
This paper has two objectives. We introduce a new global optimization algorithm reformulating optimization problems in terms
of boundary-value problems. Then, we apply this algorithm to a pointwise control problem of the viscous Burgers equation,
where the control weight coefficient is progressively decreased. The results are compared with those obtained with a genetic
algorithm and an LM-BFGS algorithm in order to check the efficiency of our method and the necessity of using global optimization
techniques. 相似文献
152.
Zhengqian Luo Guoyong Sun Zhiping Cai Miaoling Si Qibo Li 《Optics Communications》2007,277(1):118-124
In this paper, continuous wave Yb3+-doped double-clad fiber lasers (DCFLs) with linear-cavity are investigated theoretically and numerically using the rate equations. Under the steady state conditions, the simplified analytic solutions of Yb3+-doped DCFLs under considering the scattering loss are deduced in the strongly pump condition. Compared with the known analytic solutions in published literatures, our analytic solutions are more accurate, especially, at higher reflectivity of output mirror. In addition, a fast and stable algorithm based on the Newton-Raphson method is proposed to simulate numerically Yb3+-doped DCFLs. The results by simplified analytic solutions are in good agreement with those by the numerical simulation. Moreover, we have performed the optimization of an Yb3+-doped DCFL using the simplified analytic solutions and the numerical simulations, respectively. 相似文献
153.
An energy-dependent partitioning scheme is explored for extracting a small number of eigenvalues of a real symmetric matrix with the help of genetic algorithm. The proposed method is tested with matrices of different sizes (30 × 30 to 1000 × 1000). Comparison is made with Löwdin’s strategy for solving the problem. The relative advantages and disadvantages of the GA-based method are analyzed 相似文献
154.
We give a competitive algorithm to identify all d defective edges in a hypergraph with d unknown. Damaschke did the d=1 case for 2-graphs, Triesch extended the d=1 case to r-graphs, and Johann did the general d case for 2-graphs. So ours is the first attempt to solve the searching for defective edges problem in its full generality. Further, all the above three papers assumed d known. We give a competitive algorithm where d is unknown. 相似文献
155.
We consider a trader who wants to direct his or her portfolio towards a set of acceptable wealths given by a convex risk measure. We propose a Monte Carlo algorithm, whose inputs are the joint law of stock prices and the convex risk measure, and whose outputs are the numerical values of initial capital requirement and the functional form of a trading strategy for achieving acceptability. We also prove optimality of the capital obtained. Explicit theoretical evaluations of hedging strategies are extremely difficult, and we avoid the problem by resorting to such computational methods. The main idea is to utilize the finite Vapnik–C?ervonenkis dimension of a class of possible strategies. 相似文献
156.
157.
Multi-dimensional asymptotically quasi-Toeplitz Markov chains with discrete and continuous time are introduced. Ergodicity
and non-ergodicity conditions are proven. Numerically stable algorithm to calculate the stationary distribution is presented.
An application of such chains in retrial queueing models with Batch Markovian Arrival Process is briefly illustrated.
AMS Subject Classifications Primary 60K25 · 60K20 相似文献
158.
159.
160.
用遗传算法结合Gupta紧束缚模型势研究了Irn(n=2-25)团簇的基态结构.分析了Irn(n=2-25)团簇的基态结构随团簇尺寸的变化规律.计算结果表明,Irn(n=2-25)团簇的每个原子的平均束缚能和平均第一近邻随团簇尺寸的增加而增大,以总束缚能的二阶差分为判据,Irn(n=2-25)团簇的幻数是4、7、9、13、15、19、23. 相似文献