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131.
We propose a novel quantum switch teleportation with a continuous variable, which can teleport a quantum state to two different receivers alternatively, using a pair of two-mode squeezed lights as the quantum switching to manipulate the transmission route. In this scheme, the EPR entangled beams shared by sender and receivers are produced by mixing a pair of two-mode squeezed lights on one beamsplitter and separating them by using a polarizing beam splitter. The teleportation capability of this system is examined by the criteria proposed by Ralph and Lam [#!ralph!#] from a small signal quantum optical point of view. Received 20 May 2002 / Received in final form 29 July 2002 Published online 24 September 2002 RID="a" ID="a"e-mail: zhangyun@crl.go.jp  相似文献   
132.
 The specific standard described here constitutes the heart of the quality system set up by the Commissariat à l'Energie Atomique – French Atomic Energy Commission – for its main "Fundamental Research" entity, the Directorate for the Sciences of Matter. It is a coherent standard (set of shared rules and provisions laid out in a clear fashion) designed, in the first instance, to provide those taking part in research, including the hierarchy, with the means to satisfy their requirements in the field of quality. And, secondly, to create the conditions for recognition of this action by third parties, which all research entities must nowadays convince of their trustworthiness (supervisory ministries, research partners, industrial companies, etc.). This standard places particular emphasis on the preponderant roles of initiative and freedom in fundamental research, which are a prerequisite for creativity, innovation and, last but not least, the motivation of personnel.  相似文献   
133.
 An appropriate Quality approach in fundamental research should have its roots in the very principles of the "scientific method". Quality and fundamental research could thus reconcile at the condition, on the one hand, that Quality practioners understand and take into account the reality of the "science in action" and, on the other hand, that scientists improve their awareness of the new deal which is being made between science, technology and society as well as of the actual issues of Quality. A modern Quality approach, well adapted to this specific activity, should help both scientists, decision-makers and the public face the issues concerning the role of science in society in the future. In this context, I specify a number of practical proposals concerning, in particular, the adaptation of the requirements of the quality approach to the type of research, the distinction between the three major steps of a research programme (i.e. quality of the objective, the process and the results) and the encouragement of experience feedback. Received: 8 March 1998 / Accepted: 8 December 1998  相似文献   
134.
概述宁波大学地基处理中心自成立以来紧密结合宁波市工程建设中的需要,在地基处理、桩基工程质量检测等方面开展的科研开发工作,和取得的成果,这些成果在工程中的应用已取得了良好的经济和社会效益。  相似文献   
135.
We reconsider the problem of the sum and difference of two angle variables in quantum mechanics. The spectra of the sum and difference operators have widths of , but angles differing by are indistinguishable. This means that the angle sum and difference probability distributions must be cast into a range. We obtain probability distributions for the angle sum and difference and relate this problem to the representation of nonbijective canonical transformations. Received: 6 December 1997 / Revised: 15 April 1998 / Accepted: 7 May 1998  相似文献   
136.
本文介绍了强激光与固体靶相互作用产生高能质子研究中的一些重要物理问题和目前面临的挑战.回顾了强激光与固体靶相互作用中高能质子研究的历史和发展状况;简要叙述了国内外关于高能质子研究的最新进展;总结、评述了高能质子研究过程中关于高能质子的起源和加速机制等问题存在的争议以及需要进一步研究的相关问题.  相似文献   
137.
采用“悬浮载体生物深度处理、臭氧部分氧化及生物活性炭处理”等工序开发了一种新的炼油废水再生工艺技术,深度处理炼油废水。COD、BOD、NH3-N、油、硫化物、SS、细菌等主要污染物被有效去除,总出水清澈,无色无味,可满足工业用新鲜水、生活与办公、绿化等的水质要求,且处理费用低,运行稳定可靠。  相似文献   
138.
冲蚀磨损与冲蚀、空蚀交互磨损的对比研究   总被引:1,自引:0,他引:1  
基于计算流体力学(computational fluid dynamics,CFD)方法,数值对比研究了在模拟水轮机工况中不同转速时,冲蚀与冲蚀、空蚀交互作用时,转盘表面的流场(压力场、流体浓度分布),然后在转盘式磨损装置上,进行了汽液固三相冲蚀与空蚀交互磨损试验.结果表明:对于冲蚀磨损来说,随着转速增加,压力增大,在冲蚀作用下加入空蚀磨损,压力增高,磨损加剧;而对于交互磨损来说,随着转速增加,转盘表面的空蚀磨损区域从空化孔附近开始沿着转盘旋转的反方向偏移,并且磨损程度加剧;数值计算的气泡较多且压力梯度较高区域和试验转盘磨损区域基本一致,数值计算结果和试验结果吻合得较好.  相似文献   
139.
This research study deals with the numerical solutions of linear and nonlinear time-fractional subdiffusion equations of distributed order. The main aim of our approach is based on the hybrid of block-pulse functions and shifted Legendre polynomials. We produce a novel and exact operational vector for the fractional Riemann–Liouville integral and use it via the Gauss–Legendre quadrature formula and collocation method. Consequently, we reduce the proposed equations to systems of equations. The convergence and error bounds for the new method are investigated. Six problems are tested to confirm the accuracy of the proposed approach. Comparisons between the obtained numerical results and other existing methods are provided. Numerical experiments illustrate the reliability, applicability, and efficiency of the proposed method.  相似文献   
140.
本对于全局优化问题提出一个改进的进化规划算法,该算法以概率p接收基于电磁理论求出合力方向作为随机搜索方向,以概率1-p接收按正态分布产生的随机搜索方向。改进算法不仅克服了传统进化规划算法随机搜索的盲目性,而且保留了传统进化规划算法全局搜索性。本算法应用于几个典型例题,数值结果表明本算法是可行的,有效的。  相似文献   
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