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201.
完全分层多目标规划的基线算法   总被引:6,自引:1,他引:5  
本文采用基线算法求解完全分层多目标规划问题。给出了简单完全分层多目标规划基线算法的求解步骤,并对其进行了修正,从而得到完全分层多目标规划的宽容基线算法。并给出了两个计算实例。  相似文献   
202.
We define what it means for a state in a convex cone of states on a space of observables to be generalized-entangled relative to a subspace of the observables, in a general ordered linear spaces framework for operational theories. This extends the notion of ordinary entanglement in quantum information theory to a much more general framework. Some important special cases are described, in which the distinguished observables are subspaces of the observables of a quantum system, leading to results like the identification of generalized unentangled states with Lie-group-theoretic coherent states when the special observables form an irreducibly represented Lie algebra. Some open problems, including that of generalizing the semigroup of local operations with classical communication to the convex cones case, are discussed. PACS: 03.65.Ud.  相似文献   
203.
我们谈论事理数理学的发展 ,是对数学和运筹学发展简况的回顾后作出的 ,是以人们多年来逐步发现若干事理与数理有重要联系的经验为基础来谈论的。从这种观点来看 ,事理数理学的发展 ,尚处于初始阶段。从事理与数理的联系来研究问题 ,特别是研究经济发展中的理论问题 ,是大有可为的。这种研究 ,既要以经济中有关的经验、理论、统计资料为基础 ,又要有相应的计算手段 ,还要研究出一些新的数学理论和方法 ,特别是能用来处理有相互影响的数量关系的方法 ,以及用来研究包含有矛盾的事理的数学方法。本文在谈论事理数理学的一些初步研究经验之后 ,以山东大学运筹组的两项研究工作为例 ,谈谈一些实际的应用研究的经验。其中一项是在一定的简化了的情况下 ,从理论上论述如何能解决国家计划与市场经济结合的问题  相似文献   
204.
A novel packet format with non-return-to-zero (NRZ) label and duobinary carrier-suppressed return-to-zero (DCS-RZ) payload is proposed for optical packet switching networks.NRZ label is followed by DCS-RZ payload with a certain guard time.The spectra of the low-rate NRZ label locate around the optical carrier frequency where some parts of the corresponding spectra of the high-rate DCS-RZ payload have been suppressed due to DCS-RZ modulation.At the switching node,the label or payload extraction can be realized simply through an optical bandpass or notch filter respectively.The feasibility of the scheme is verified by the simulation on the famous photonic design platform designed by Virtual Photonics Inc.(VPI).The effects of optical filter bandwidth on the received signal quality are discussed by analyzing bit error rate(BER)and contrast ratio performances.  相似文献   
205.
"求线性规划问题可行基的一种方法"的注记   总被引:1,自引:1,他引:0  
文[2]通过两个反例的计算,认为文[1]所提出的求LP可行基的方法有不妥之处,并对[1]的方法中主要步骤作了修正。本文对[1]的算法中轴心项的选取作进一步说明,对[2]中所提出的反例以[1]中算法进行计算与[2]对比分析,说明[2]中的反例并不成立。  相似文献   
206.
This article presents the realization of many self-reversible quantum logic gates using two-qubit quadrupolar spin 3/2 systems. Such operations are theoretically described using propagation matrices for the RF pulses that include the effect of the quadrupolar evolution during the pulses. Experimental demonstrations are performed using a generalized form of the recently developed method for quantum state tomography in spin 3/2 systems. By doing so, the possibility of controlling relative phases of superimposed pseudo-pure states is demonstrated. In addition, many aspects of the effect of the quadrupolar evolution, occurring during the RF pulses, on the quantum operations performance are discussed. Most of the procedures presented can be easily adapted to describe selective pulses of higher spin systems (>3/2) and for spin 1/2 under J couplings.  相似文献   
207.

Boneh and Venkatesan have recently proposed a polynomial time algorithm for recovering a ``hidden' element of a finite field of elements from rather short strings of the most significant bits of the remainder modulo of for several values of selected uniformly at random from . Unfortunately the applications to the computational security of most significant bits of private keys of some finite field exponentiation based cryptosystems given by Boneh and Venkatesan are not quite correct. For the Diffie-Hellman cryptosystem the result of Boneh and Venkatesan has been corrected and generalized in our recent paper. Here a similar analysis is given for the Shamir message passing scheme. The results depend on some bounds of exponential sums.

  相似文献   

208.
李建龙 《中国物理》2007,16(2):340-345
Stochastic resonance (SR) is based on the cooperative effect between the stochastic dynamical system and the external forcing. As is well known, the cooperative effect is produced by adding noises. In this paper, we show the evidence that by changing the system parameters and the signal intensity, a nonlinear system in the presence of an input aperiodic signal can yield the cooperative effect, with the noise fixed. To quantify the nonlinear system output, we determine the theoretical bit error rate (BER). By numerical simulation, the validity of the theoretical derivation is checked. Besides, we show that parameter-induced SR is more realizable than SR via adding noises, especially when the noise intensity exceeds the resonance level, or when the characteristic of the noise is not known.  相似文献   
209.
In this paper we develop a new model for harvest operation costs that can be used to evaluate stands for potential harvest. The model is based on felling, extraction, and access costs and is unique in its consideration of the interaction between harvest area shapes and access roads. We illustrate the model and evaluate the impact of stand size, volume, and road cost when determining harvest layouts. We also present a generalized case where multiple unit road costs are considered in the same stand.  相似文献   
210.
在石油钻井中,滑动轴承牙轮钻头的应用日益增多,但轴承的工作环境却相当恶劣。为了提高钻头滑动轴承的工作寿命,并为这类轴承的设计提供科学依据,针对其实际应用工况,特殊设计制造了一种IPG-2型滑动轴承试验台,并且利用其在30kN、40kN和50kN的3种载荷条件下,对牙轮钻头镶嵌铜合金的滑动轴承进行了台架试验研究,着重考察了铜合金镶嵌区尺寸之大小对轴承摩擦磨损性能的影响。结果表明,在相邻两个镶嵌区之间的基体区表面宽度与铜合金的镶嵌区宽度之比值分别为1、2、3和4的几种镶嵌滑动轴承中,它们的摩擦学性能依次变差,即以第一种镶嵌轴承的摩擦磨损性能最好,这是由于镶嵌材料铜合金的抗剪切强度比钢基体的低,在摩擦力的作用下容易向非镶嵌区基体表面及与之对摩部件表面发生材料转移并形成转移膜的缘故。这种研究结果可以直接应用于钻头滑动轴承的设计。  相似文献   
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