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1.
《Indagationes Mathematicae》2021,32(6):1229-1239
2.
ZHAO Shan-Rong CHEN Kai-Xian JIANG Hua-Liang WANG Qin-Mi JI Ru-YunShanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai China 《中国化学》1997,15(1):84-89
We have used quantum mechanical method to study the transition states(TSs) of uridine phosphorolysis reaction. Comparing the four different reaction pathways and the five transition states obtained, we conclude that enzymatic uridine phosphorolysis takes place mainly according to acid-catalyzed SN2 mechanism. The proposed reaction pathway is consistent with many experimental results. 相似文献
3.
4.
R. J. Vanderbei 《Mathematical Programming》1989,43(1-3):31-44
The affine-scaling modification of Karmarkar's algorithm is extended to solve problems with free variables. This extended primal algorithm is used to prove two important results. First the geometrically elegant feasibility algorithm proposed by Chandru and Kochar is the same algorithm as the one obtained by appending a single column of residuals to the constraint matrix. Second the dual algorithm as first described by Adler et al., is the same as the extended primal algorithm applied to the dual. 相似文献
5.
通过分析计算,设计了一种大口径宽视场折射式红外相机光学系统。该系统设计用于超长线阵扫描红外相机的地面演示成像,它能同时对短波2μm—3μm、中波3μm—4.5μm双波段成像,且同时具有24°的大视场和150mm的宽口径,成像质量接近衍射极限。该系统在航天遥感领域应用广泛。 相似文献
6.
Nobuhiro Honda 《Mathematische Nachrichten》2003,256(1):48-57
In a previous paper of the same title the author gave a generalization of the constrution of Donaldson–Friedman, to prove the existence of twistor spaces of n CP 2 with a special kind of divisors. In the present paper, we consider its equivariant version. When n = 3, this gives another proof of the existence of degenerate double solid with C *–action, and we show that the branch quartic surface is birational to an elliptic ruled surface. In case n ≥ 4, this yields new Moishezon twistor spaces with C *–action, which is shown to be the most degenerate ones among twistor spaces studied by Campana and Kreußler. 相似文献
7.
The turbulent flow in a compound meandering channel with a rectangular cross section is one of the most complicated turbulent flows, because the flow behaviour is influenced by several kinds of forces, including centrifugal forces, pressure‐driven forces and shear stresses generated by momentum transfer between the main channel and the flood plain. Numerical analysis has been performed for the fully developed turbulent flow in a compound meandering open‐channel flow using an algebraic Reynolds stress model. The boundary‐fitted coordinate system is introduced as a method for coordinate transformation in order to set the boundary conditions along the complicated shape of the meandering open channel. The turbulence model consists of transport equations for turbulent energy and dissipation, in conjunction with an algebraic stress model based on the Reynolds stress transport equations. With reference to the pressure–strain term, we have made use of a modified pressure–strain term. The boundary condition of the fluctuating vertical velocity is set to zero not only for the free surface, but also for computational grid points next to the free surface, because experimental results have shown that the fluctuating vertical velocity approaches zero near the free surface. In order to examine the validity of the present numerical method and the turbulent model, the calculated results are compared with experimental data measured by laser Doppler anemometer. In addition, the compound meandering open channel is clarified somewhat based on the calculated results. As a result of the analysis, the present algebraic Reynolds stress model is shown to be able to reasonably predict the turbulent flow in a compound meandering open channel. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
8.
线性规划联合算法的理论与应用 总被引:6,自引:4,他引:2
本在[1]的基础上.较系统的叙述了线性规划联合算法的步骤、相关理论及其应用,指出该算法具有避免人工变量、减少迭代次数、使用灵活、应用方便等特点。 相似文献
9.
The problem of finding the Euclidean distance between two convex polyhedra can be reduced to the combinatorial optimization problem of finding the minimum distance between their faces. This paper presents a global optimality criterion for this problem. An algorithm (QLDPA) for the fast computation of the distance between convex and bounded polyhedra is proposed as an application of it. Computer experiments show its fast performance, especially when the total number of vertices is large. 相似文献
10.
The exponential functional of simple, symmetric random walks with negative
drift is an infinite polynomial Y = 1 + ξ1 + ξ1ξ2 + ξ1ξ2ξ3 + ⋯ of independent
and identically distributed non-negative random variables. It has moments that are
rational functions of the variables μ
k
= E(ξ
k
) < 1 with universal coefficients. It
turns out that such a coefficient is equal to the number of permutations with descent
set defined by the multiindex of the coefficient. A recursion enumerates all numbers
of permutations with given descent sets in the form of a Pascal-type triangle.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献