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61.
The coupled numerical simulation on fluid flow, heat transfer, and mass transfer in the process of laser cladding is undertaken on the basis of the continuum model.In the simulation of mass transfer in the laser molten pool, the concentration distribution in the regions on different sides of the interface between cladding layer and substrate is calculated separately and coupled at the co-boundary.The non-equilibrium solute partition coefficient is obtained from equilibrium solute partition coefficient according to the Sobolev model.By using the developed software which is based on the commercial software PHOENICS 1.4, the distribution of Fe in laser molten pool in an experiment of cladding Stellite 6 on 12CrMoV is calculated.The obtained results well coincide with the experimental ones. 相似文献
62.
模糊广义判断矩阵的一致性检验及合成排序 总被引:3,自引:0,他引:3
决策评价过程中往往包含诸多不确定性、随机性和模糊性,广义判断下的AHP-GJAHP是一种广义AHP,Fuzzy 环境下的GJAHP决策方法是应用集值统计的方法,在区间判断标度基础上确定模糊判断矩阵元素的正模糊数表示,并根据模糊集理论的扩展原理,求得Fuzzy 环境下的模糊排序权值向量。本文给出模糊广义判断矩阵的一致性定义,讨论了各类判断形式条件下的一致性检验法与Fuzzy 环境下递阶层次结构中的合成排序问题 相似文献
63.
M.J. Kaiser 《Applied Mathematics Letters》1996,9(6):67-70
Based on Gage's notion of a “positive center” of a planar convex set, an ε-positive center figure is defined, constructed, and illustrated through example. The existence of an ε-positive center point, and the convexity of the ε-positive center figure, is conjectured. 相似文献
64.
Summary This paper is concerned with the study of a newM/G/1 retrial queueing system in which the delays between retrials are exponentially distributed random variables with linear intensityg(n)=α+nμ, when there aren≥1 customers in the retrial group. This new retrial discipline will be calledlinear control policy. We carry out an extensive analysis of the model, including existence of stationary regime, stationary distribution of the
embedded Markov chain at epochs of service completions, joint distribution of the orbit size and the server state in steady
state and busy period. The results agree with known results for special cases. 相似文献
65.
Rate of Convergence for the Empirical Distribution Function and the Empirical Characteristic Function of Mixing ProcessesHuSh... 相似文献
66.
Thermal Aqueous Liquid Chromatography (TALC) using pure water as a mobile phase should be a very attractive technique promoting the use of liquid chromatography in routine analysis, either in the laboratory or in future on-line process control. This simple form of chromatography, the selectivity of which depends on the fixed phase only, would allow the use of flame ionization as an almost universal, low-cost detector in liquid chromatography. The potential of the TALC technique is illustrated by selected examples. 相似文献
67.
Das R Kumar SK Kumar A 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2005,177(2):318-328
Geometric phases have stimulated researchers for its potential applications in many areas of science. One of them is fault-tolerant quantum computation. A preliminary requisite of quantum computation is the implementation of controlled dynamics of qubits. In controlled dynamics, one qubit undergoes coherent evolution and acquires appropriate phase, depending on the state of other qubits. If the evolution is geometric, then the phase acquired depend only on the geometry of the path executed, and is robust against certain types of error. This phenomenon leads to an inherently fault-tolerant quantum computation. Here we suggest a technique of using non-adiabatic geometric phase for quantum computation, using selective excitation. In a two-qubit system, we selectively evolve a suitable subsystem where the control qubit is in state |1, through a closed circuit. By this evolution, the target qubit gains a phase controlled by the state of the control qubit. Using the non-adiabatic geometric phase we demonstrate implementation of Deutsch-Jozsa algorithm and Grover's search algorithm in a two-qubit system. 相似文献
68.
We consider a space of Chebyshev splines whose left and right derivatives
satisfy linear constraints that are given by arbitrary nonsingular connection matrices.
We show that for almost all knot sequences such spline spaces have basis functions
whose support is equal to the support of the ordinary B-splines with the same knots.
Consequently, there are knot insertion and evaluation algorithms analogous to de Boors
algorithm for ordinary splines. 相似文献
69.
Yeh Lam 《应用数学学报(英文版)》2003,19(3):405-416
Geometric process (GP) was introduced by Lam[4,5], it is defined as a stochastic process {Xn, n = 1, 2,…} for which there exists a real number a > 0, such that {an-1 Xn, n = 1,2, …} forms a renewal process (RP). In this paper, we study some limit theorems in GP. We first derive the Wald equation for GP and then obtain the limit theorems of the age, residual life and the total life at t for a GP. A general limit theorem for Sn with a > 1 is also studied. Furthermore, we make a comparison between GP and RP, including the comparison of their limit distributions of the age, residual life and the total life at t. 相似文献
70.
A. Chaudhury R. Khatirkar N.N. Viswanathan V. Singal A. Ingle S. Joshi I. Samajdar 《Journal of magnetism and magnetic materials》2007
Commercial supply, from several steel manufacturers, of low-silicon non-grain-oriented electrical steel was monitored over a span of several years. A total of 51 samples were selected—selected from many hundreds on the basis of large differences in magnetic properties, but absence of significant variations in chemistry (other than differences in silicon percentage). The selected samples were analyzed for crystallographic texture and for grain size. 相似文献