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141.
142.
Y. Ozmen 《Experimental Thermal and Fluid Science》2011,35(2):355-363
An experimental study is carried out to investigate flow characteristics of confined twin jets issuing from the lower surface and impinging normally on the upper surface. Pressure distributions on the impingement and confinement plates were obtained for Reynolds numbers ranging from 30,000 to 50,000, nozzle-to-plate spacing (H/D) in the range of 0.5-4 and jet-to-jet spacing (L/D) in the range of 0.5-2. Smoke-wire technique was used to visualize the flow behavior. The effects of Reynolds number, nozzle-to-plate spacing and jet-to-jet spacing on the flow structure are examined. The subatmospheric regions occur on both impingement and confinement plates at the nozzle-to-plate spacing up to 1 for all studied Reynolds numbers and jet-to-jet spacings in consideration. They lie nearly up to the same radial location at both surfaces and move radially outward from the stagnation points with increasing nozzle-to-plate spacing and jet-to-jet spacing. It is concluded that there exists a relation between the subatmospheric regions and peaks in heat transfer coefficients for low spacings in the impinging jets. 相似文献
143.
144.
设计了一个新的求解等式约束优化问题的非单调信赖域算法.该算法不需要罚函数也无需滤子.在每次迭代过程中只需求解满足下降条件的拟法向步及切向步.新算法产生的迭代步比滤子方法更易接受,计算量比单调算法小.在一般条件下,算法具有全局收敛性. 相似文献
145.
This paper has presented transparent conductor oxide materials (TCOMs) based microstrip patch antennas with glass substrate and copper ground plane, which have been deeply analyzed in the visible spectrum region in comparison with the practical patch antenna model of indium tin oxide patch with glass substrate and different TCOMs based ground plane. As well as the study have investigated the effect of transparent oxide materials on patch antenna design instead of perfect conductor materials such as copper that has low cost and weight. The tradeoff between optical transparency and electrical conductivity will be evaluated for a range of visible regions. Microstrip transmission line feed method is used to predict the skin effects on a patch antenna and their impact on antenna efficiency, resonance frequency and optical transmission are also described. This study have discussed assessment of these tradeoffs and effect of TCOMs parameters on antenna design. 相似文献
146.
For the first time, we numerically demonstrate that similaritons in passive fibers can only propagate with parabolic profile without oscillations in a limited self-similar propagation region when low-order approximation is applied. Dispersion-decreasing fiber (DDF) and nonlinearity increasing fiber (NIF) are used here to generate self-similar pulse in different passive ways. Moreover, we put forward several self-similar features to judge effective similariton propagation and determine self-similar region by numerical simulations and waveform observation. Finally we compare in DDF and NIF the dependence of these regions on incident pulse and fiber parameters in order to obtain parabolic similariton more effectively and steadily. These results extend the low-order propagation properties in passive fibers and are beneficial for the generation of high-quality similariton pulse by parameter selection in experimental studies and practical applications. 相似文献
147.
Loopy belief propagation (LBP) algorithm over pairwise-connected Markov random fields (MRFs) has become widely used for low-level vision problems. However, Pairwise MRF is often insufficient to capture the statistics of natural images well, and LBP is still extremely slow for application on an MRF with large discrete label space. To solve these problems, the present study proposes a new segmentation algorithm based on adaptive LBP. The proposed algorithm utilizes local region information to construct a local region model, as well as a local interaction region MRF model for image segmentation. The adaptive LBP algorithm maximizes the global probability of the proposed MRF model, which employs two very important strategies, namely, “message self-convergence” and “adaptive label pruning”. Message self-convergence can improve the reliability of a pixel in choosing a label in local region, and label pruning can dismiss impossible labels for every pixel. Thus, the most reliable information messages transfer through the LBP algorithm. The experimental results show that the proposed algorithm not only obtains more accurate segmentation results but also greater speed. 相似文献
148.
基于联合实施微观相互作用玻色子模型的最大F旋方案 (sdIBM-Fmax)与γ射线能量-自旋曲线 (γ-ray energy over spin curves, E-GOS)方案, 成功描述了182Os核yrast带相继的SU(3)–U(5)–SU(3)结构相变, 由于缺少直观解释而显得抽象. 本文借助微观sdIBM-Fmax的微观参数与Bohr哈密顿量的势能曲面方程之间存在的泛函关系, 几何地给出了对这种相继相变途径的另外一种可能理解; 并阐述了在完全变形核的高角动量态中, 由于量子效应在高激发态与低激发态之间生成高简并的临界区, 提供了γ振动能量会变得低于转动能量的一个可能途径, 从而实现了SU(3)–U(5)的相变.
关键词:
yrast带结构演化
势能曲面
相变临界区
182Os核')" href="#">182Os核 相似文献
149.
Efficiency evaluations in data envelopment analysis are shown to be stable for arbitrary perturbations in the convex hulls of input and output data. Also, the corresponding restricted Lagrange multiplier functions are shown to be continuous. The results are proved using point-to-set mappings and a particular region of stability from input optimization.Research partly supported by National Science Foundation Grants, Office of Naval Research Grant, and by the Natural Sciences and Engineering Council of Canada. 相似文献
150.
Daniel Girela M. Auxiliadora Márquez 《Journal of Mathematical Analysis and Applications》2005,309(2):534-543
A well-known theorem of H.S. Shapiro and A.L. Shields implies that if f?0 is a function which belongs to the Bergman space Ap (0<p<∞) and {zk} is a sequence of zeros of f which is contained in a Stolz angle, then {zk} satisfies the Blaschke condition. In this paper we improve this result. We consider a large class of regions contained in the unit disc D which touch ∂D at a point ξ tangentially and we prove that the mentioned result remains true if we substitute a Stolz angle by any of these regions of tangential approach. 相似文献