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131.
在二值和多值逻辑研究中,最常用的两种函数表达式是基于格代数的SOP表达式和基于Galois域的Reed-Muller展式(RM展式)。由RM展式实现的电路由于具有故障诊断容易和线性运算功能,因而在可靠性设计、编码理论和数字通信中得到了广泛的应用。然而,RM展式系数向量不象SOP表达式那样与函数值向量有直接对应关系,因此RM展式系数向 相似文献
132.
Generalized expression of exergy in the thermodynamics 总被引:6,自引:0,他引:6
Exergy is the ability of the maximum work done to the objective (relative) outside when the system changes from any state
to its dead state. Exergy stems from the gaps of intensive properties between its present state and its dead state. Generalized
differential expression of exergy is advanced without any premise conditions, which is composed of generalized intensive and
extensive (additive) properties. Any form of exergy can be deduced out from this generalized expression, only if its characteristic
intensive and extensive parameters are known. That the exergy of any closed system is never below zero has been proved. 相似文献
133.
Yikun Bu Quan Zheng Qinghua Xue Yingxin Cheng Longsheng Qian 《Optics & Laser Technology》2006,38(8):565-568
A design of LD-pumped Nd:YVO4 laser that generates simultaneous laser action at wavelengths 1064 and 1342 nm by optimizing film design is presented. An optimized continuous-wave (cw) yellow laser at 593.5 nm in room temperature is obtained for the first time. Using type-I critical phase-matching (CPM)LBO crystal, a yellow laser at 593.5 nm is obtained by 1064 and 1342 nm intracavity sum-frequency mixing. The maximum laser output power of 85 mW is obtained when an incident pump laser of 1.8 W is used. The optical-to-optical conversion is up to 4.7%, and the power stability in 24 h is better than ±2.8%. 相似文献
134.
Using linear approximation method, we calculate the intensity correlation time of a single-mode laser driven by both colored pump noise with signal modulation and the quantum noise with cross-correlation between its real and imaginary parts, and analyze the influence of the net gain coefficient a0 on the statistical fluctuation of the laser system. It is found that for the case that the colored pump noise is long time correlated, the main factor influencing the statistical fluctuation of the laser system is a0, and the frequency of the modulation signal has negligible effect on the statistical fluctuation of the laser system. 相似文献
135.
若代数A和B导出等价,则它们的Repetitive代数A和B也是导出等价,从而是稳定等价.这样利用更直接的代数方法完全回答了H.Asashiba提出的问题,并推广了Rickard,杜先能,Tachikawa-Wakamatsu等人的相应结果.进而,把以上结果推广到上有界复形的导出范畴的对称recollement的情形. 相似文献
136.
The determination of an equivalent elastic modulus for bodies with cracks by boundary element method
The equivalent elastic modulus of cracked bodies with orderly distributed cracks was computed with the boundary element method. A practical self-consistent scheme has been proposed in consideration of the mutual interaction effects of the cracks. The influence of friction coefficients and orientation of cracks has been investigated. Some computational examples have been given, and the results show that the proposed method is adequate and the scheme is efficient.This project is supported by the National Natural Science Foundation of China. 相似文献
137.
In this paper, we consider the unilateral obstacle problem, trying to find the numerical solution and coincidence set. We construct an equivalent format of the original problem and propose a method with a second-order in time dissipative system for solving the equivalent format. Several numerical examples are given to illustrate the effectiveness and stability of the proposed algorithm. Convergence speed comparisons with existent numerical algorithm are also provided and our algorithm is fast. 相似文献
138.
139.
Oscillatory and asymptotic criteria of third order nonlinear delay dynamic equations with damping term on time scales 下载免费PDF全文
Qinghua Feng 《Journal of Applied Analysis & Computation》2018,8(4):1260-1281
In this paper, we are concerned with oscillatory and asymptotic behavior of third order nonlinear delay dynamic equations with damping term on time scales. By using a generalized Riccati function and inequality technique, we establish some new oscillatory and asymptotic criteria. The established results on one hand extend some known results in the literature, on the other hand unify continuous and discrete analysis as two special cases of an arbitrary time scale. We also present some applications for the established results. 相似文献
140.
The paper discusses a general framework for outer approximation type algorithms for the canonical DC optimization problem.
The algorithms rely on a polar reformulation of the problem and exploit an approximated oracle in order to check global optimality.
Consequently, approximate optimality conditions are introduced and bounds on the quality of the approximate global optimal
solution are obtained. A thorough analysis of properties which guarantee convergence is carried out; two families of conditions
are introduced which lead to design six implementable algorithms, whose convergence can be proved within a unified framework. 相似文献