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排序方式: 共有1094条查询结果,搜索用时 15 毫秒
71.
Nonlinear Dynamics - In this paper, we investigate a general integrable three-component coupled nonlocal nonlinear Schrödinger system with the parity-time symmetry. The general Nth Darboux... 相似文献
72.
The unsteady, three-dimensional full Navier-Stokes equations are solved using a Beam-Warming implicit algorithm in this paper. Computations of the flow over a 76° sweep delta wing at 36.5° angle of attack is presented. The sectional streamlines are depicted and the evolution of the instantaneous crossflow topology of the leading-edge vortex is analyzed. It is found that, along the axis, the topology of the primary vortex alters several times starting from stable focus near the apex to unstable focus, and lasts back to stable focus near wake edge; The stable limit cycle and unstable limit cycle are shown in this evolution. These various altering topologies stem from the stretching and compression of the vortex core. 相似文献
73.
本文给出了一类非时齐的Markov链的强逼近.作为应用,建立了临床试验中Markov链自适应设计的强相合性,重对数律和弱收敛. 相似文献
74.
Arrangement transformation approach (ATA) for doing state-to-state quantum reactive scattering calculations of atom-diatom
systems is given. The state-to-state results of H + DH on ISTH potential energy surface are presented, and it can be deduced
from the results that the ATA method can be used for the system with more than three atoms.
Project supported by the National Natural Science Foundation of China (Grant No. 19774038) and Shandong Science Foundation
(Grant No. Y96A08012). 相似文献
75.
铂(Ⅳ)-钼酸盐-乙基罗丹明B离子缔合显色反应研究 总被引:2,自引:0,他引:2
本文研究了在聚乙烯醇(PVA)存在下用钼酸盐与乙基罗丹明B(ERB)形成离子缔合物,该缔合物的最大吸收位于580nm,摩尔吸光系数为1.12×106L·mol-1·cm-1,服从比耳定律范围0—2.5μg/25mL,缔合物至少稳定1周,考察了50多种共存离子的影响,除生成杂多酸元素和Au(Ⅲ)、Os(Ⅷ)、Pd(Ⅱ)、Ir(Ⅳ)外,大多数元素不干扰。测定铂的条件为:〔HClO4〕=1.2mol/L,〔MoO42-〕=9.1×10-4mol/L,〔ERB〕=3.2×10-5mol/L,0.08%PVA。缔合物的摩尔比为Pt(Ⅳ)∶ERB=1∶2,本法已用于铂矿中铂的测定,结果满意。 相似文献
76.
In this paper, we investigate the production order scheduling problem derived from the production of steel sheets in Shanghai Baoshan Iron and Steel Complex (Baosteel). A deterministic mixed integer programming (MIP) model for scheduling production orders on some critical and bottleneck operations in Baosteel is presented in which practical technological constraints have been considered. The objective is to determine the starting and ending times of production orders on corresponding operations under capacity constraints for minimizing the sum of weighted completion times of all orders. Due to large numbers of variables and constraints in the model, a decomposition solution methodology based on a synergistic combination of Lagrangian relaxation, linear programming and heuristics is developed. Unlike the commonly used method of relaxing capacity constraints, this methodology alternatively relaxes constraints coupling integer variables with continuous variables which are introduced to the objective function by Lagrangian multipliers. The Lagrangian relaxed problem can be decomposed into two sub-problems by separating continuous variables from integer ones. The sub-problem that relates to continuous variables is a linear programming problem which can be solved using standard software package OSL, while the other sub-problem is an integer programming problem which can be solved optimally by further decomposition. The subgradient optimization method is used to update Lagrangian multipliers. A production order scheduling simulation system for Baosteel is developed by embedding the above Lagrangian heuristics. Computational results for problems with up to 100 orders show that the proposed Lagrangian relaxation method is stable and can find good solutions within a reasonable time. 相似文献
77.
78.
将二维人工脑模型推广到三维,并给出了一个实际应用算例,还将二、三维模型的计算结果进行了对比,发现三维模型的计算效果明显优于二维模型。 相似文献
79.
表面分形球、柱的光散射 总被引:2,自引:0,他引:2
分形和分维是近些年才兴起的一门处理复杂事物的新方法 ̄[1]。本文主要研究具有表面分形的球、柱的光散射特征。我们首先利用几何光学近似研究了一种表面满足自仿射原理的分形均匀球的散射,其散射特性与分维存在一定的关系。我们还利用微扰法讨论了表面具有沟槽的分形柱的光散射的分形特征。 相似文献
80.
The time resolved polarized CARS technique has been used to detect Cl atoms produced by photolysis of ICl in the presence and absence of O2. A population inversion was observed between the ground state electronic levels Cl(2
P
1/2) and Cl(2
P
3/2). The rate constant for Cl(2
P
1/2) decay (quenching + reaction) in ICl was determined to be (3.2±0.2)×10–13 cm3/molecule×s; the rate constant for Cl(2
P
3/2) reaction with ICl was determined to be (7.8±0.5)×10–12 cm3/molecule×s; and the rate constant for Cl(2
P
1/2) quenching by O2 was determined to be (1.9±0.2)×10–13 cm3/molecule×s. 相似文献