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11.
Alessandro Fantoni Manuela Viera Rodrigo Martins 《Solar Energy Materials & Solar Cells》2002,73(2):148
In this paper a set of one-dimensional simulations of a-Si:H p–i–n junctions under different illumination conditions and with different intrinsic layer are presented. The simulation program ASCA permits the analysis of the internal electrical behaviour of the cell allowing a comparison among the different internal configurations determined by a change in the input set. Results about the internal electric configuration will be presented and discussed outlining their influence on the current tension characteristic curve. Considerations about the drift–diffusion and the generation–recombination balance distributions, outlined by the simulation, can be used to explain the correlation between the basic device output, the i-layer characteristics (thickness and DOS), the incident radiation intensity and photon energy. 相似文献
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A method is considered to solve a conditional optimization problem with a linear-fractional objective function over permutations.
The performance of sub algorithms to solve this problem is evaluated. The practical efficiency of the algorithm is analyzed
by conducting numerical experiments.
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Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 133–146, July–August 2007. 相似文献
14.
裂齿矩形翅片板翅式换热器优化设计的分析 总被引:2,自引:0,他引:2
对裂齿矩形翅片板翅式换热器中的裂齿矩形翅片的传热效率作了分析,并以单位质量材耗的换热能力最大为目标函数,分析研究了在不同雷诺数(Re)的操作条件下裂齿矩形翅片间角度、翅片厚、长度、宽度及极厚之间的关系。结果表明:在气体换热的场合下,当Re在某一范围时翅片可有效地起到强化传热的作用。当板厚为5mm,翅片厚为3mm,翅片间夹角为45°~70°,Re为2×10~3~8×10~3,最佳翅片纵向间距与翅片长度和翅片厚度乘积的平方根的比为1.5~2.5,最佳翅片尺寸系数为3~5时,传热强化效果较好。 相似文献
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We describe a Gauss–Seidel algorithm for optimizing a three‐dimensional unstructured grid so as to conform to a given metric. The objective function for the optimization process is based on the maximum value of an elemental residual measuring the distance of any simplex in the grid to the local target metric. We analyse different possible choices for the objective function, and we highlight their relative merits and deficiencies. Alternative strategies for conducting the optimization are compared and contrasted in terms of resulting grid quality and computational costs. Numerical simulations are used for demonstrating the features of the proposed methodology, and for studying some of its characteristics. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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The anisotropic nature of fibre reinforced composites leads to large stress concentrations around pin-loaded holes through standard weave cloths. Proper understanding of how this anisotropic nature affects the load distribution around holes can be utilised to reduce these concentrations if sufficient thought is given to the internal fibre geometry near to the hole. Such local reinforcements need not be highly complex and can be readily produced without excessive effort, producing significant improvements in performance. 相似文献
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The problem of determining the maximum mean response level crossing rate of a linear system driven by a partially specified Gaussian load process has been considered. The partial specification of the load is given only in terms of its total average energy. The critical input power spectral (PSD) function, which maximizes the mean response level crossing rate, is obtained. The critical input PSD turns out to be highly narrow-banded which fails to capture the erratic nature of the excitation. Consequently, the trade-off curve between the maximum mean response level crossing rate and the maximum disorder in the input process, quantified in terms of its entropy rate, has been generated. The method of Pareto optimization is used to tackle the conflicting objectives of the simultaneous maximization of the mean response level crossing rate and the input entropy rate. The non-linear multi-objective optimization has been carried out using a recently developed multi-criteria genetic algorithm scheme. Illustrative example of determining the critical input of an axially vibrating rod, excited by a partially specified stationary Gaussian load process, has been considered. 相似文献