美军武器装备研制,试验,评价和采购体系的改革计划

主题:国防部研究、发展、试验与评价(RDT＆E)、采办规计的合理化管理。 国防部机构,陆军、空军、海军、国防高级研究规划局(DARPA)、国防工业供应局(DISA)、国防核武器局(DNA)、战略防御倡议组织(SDIO)。 问题:国防部关于研究、发展、试验与评价(RDT＆E)规划的合理化管理的目标是减     

北京谱仪(BES) 轻子识别研究——Monte Carlo结果

这项工作是详细研究北京谱仪(BES)轻子识别的一部分。本文报告了π/μ、π/e分辨的Monte Carlo 结果。结果表明:在北京谱仪中π/μ分辨有两个有效的截断,即位置与方向。对于π/μ分辨也有两个有效的截断,即总电荷量沉积和二极矩。     

3维C/SiC-ZrC复合材料的制备及其性能研究

针对超高温环境应用需求,采用化学气相渗透工艺(CVI)与先驱体浸渍-裂解工艺(PIP)联用制备了3维碳纤维增强SiC-ZrC基复合材料(C/SiC-zrC),并研究了SiC含量对C/SiC-ZrC复合材料力学性能、抗氧化性能和抗烧蚀性能的影响.结果表明,随着SiC含量的增加,C/SiC-ZrC复合材料的强度逐渐降低,静...     

突破,在新的起点

正主持人语:7月11日,兵团党委六届十三次全委(扩大)会议召开,兵团党委书记、政委车俊在报告中提出,兵团各级要重点在提高维稳戍边能力、壮大南疆兵团力量、深化兵地融合发展、打造兵团文化高地、丰富完善党政军企合一体制等方面努力取得突破。"五个突破",为兵团下一步工作指明了着眼点和着力点。维稳戍边是兵团的看家本领和职责所在,"在提高维稳戍边能力、推动建立兵地一体的维稳机制上要取得新突破",要求我们必须坚持提高总量、提高素质、提高能力,切实做好维护新     

北京三兴汽车厂在新产品开发中不断前进

北京三兴汽车厂(中国人民解放军第3603工厂)是总后新兴(集团)总公司直属的国家大型二类企业。遵照上级的统一部署,该厂成功地开发了以军用为主,兼以民用的轻型客车系列产品,设计独特获国家专利(专利号ZL93243297.2)的商用计量加油车等系列产品。轻型客车车身覆盖中全部采用引进模具,利用优质钢板冲压成型,具有型线整齐,曲面平顺,外观质量优良,密封性能良好等特点,已达国外同类的同等水平。利用该车身装配的国产越野车,经部队批量试用后,不开裂,不变型,深受部队基层的欢迎。北京三兴轻型客车目前有BSX6470、BSX6471和BSX6472三大系列。该车具有结构紧凑,设计先进,合理,操作灵活,行驶平稳等特点,乘坐舒适,越野能力强,车身外型流畅,内装修豪华,装有进口冷热风空调装置。该车     

如何加强初中化学实验教学

《九年义务教育全日制初级中学化学教学大纲(试用)》(以下简称新大纲)指出:“化学是一门以实验为基础的学科。实验教学可以激发学生学习化学的兴趣,帮助学生形成化学概念,获得化学知识和实验技能,培养观察和实验能力,还有助于培养实事求是、严肃认真的科学态度和科学的学习方法     

过程能力与计数值过程能力指数计算

一、过程能力过程能力在制造业中又叫工序能力。它是指工序中人、机、料、法、环、测诸因素均处于受控状态下,过程加工质量满足技术标准的能力,是对过程加工内在质量特性一致性的度量。通常,过程能力以B表示,是标准差的6倍,即:B=6σ(1)如果采用x-R控制图法,则:B=6R/d2(2)式中:R——平均极差;d2——由每组样本大小n决定的系数,可通过查阅作控制图的相关数据表而得。事实上,即使控制得再好的过程也存在着波动,这是由于人、机、料、法、环、测诸因素随时都会产生变化的原因,如:设备各部分磨损、刀具自然磨损、温度及化学变化等。也就是说,过…     

基于遗传算法的(n,n-1,m)卷积码盲识别

针对信息截获领域中(n,n-1,m)卷积码盲识别问题,提出基于遗传算法的盲识别方法。该方法在矩阵分析得到编码参数之后,利用遗传算法的全局搜索能力实现对基本校验多项式矩阵的精确识别,进而实现对基本生成多项式矩阵的识别。仿真表明:该方法能够在高误码条件下实现对(n,n-1,m)卷积码的盲识别,且运算量相对于以往的高容错识别方法得到降低。     

一种用于直线度测量的多功能,简单,低成本电容传感器

线性运动在精密工程中被广泛应用。由于寄生运动的存在,要实现线性工作台或轴承完美无缺的直线运动几乎是不可能的。这些寄生运动包括:两个方向的平动(y和z),三个方向的转动,即滚动(Φ_x),垂直俯仰(Φ_y),水平晃动(Φ_z)。使用机械元件,这些寄生运动的数量级分别为1μm和1mrad。修改机械设计来增加直线运动的精度通常是困难的而     

程控用户交换机的中继方式及数字中继模块的设计与实现

本文史介绍一种程控用户交换机数字中继模块的实现方法。它以加拿大 MITEL 公司的MH89780数字中继接口芯片(CEPT Digital Trunk Interface Hybrid)和 MT8980(8×32)时隙交换矩阵芯片(Digital Time/Space Crosspoint Switch)为基础来实现数字中继接口功能。这种中继电路为程控用户交换机进入公用电话网提供了全自功入网能力,并易于进行程控用户交换机之间的组网。数字中继采用 PCM30/32路系统,可以采用随路信令,也可以采用公共信道信令。     

Cell structure of microcellular combustible object foamed by supercritical carbon dioxide

In order to solve the issue that the combustible objects for cased telescoped ammunition (CTA) didn't burn completely during the combustion process, the microcellular combustible objects were foamed with numerous cells in the micron order to improve the combustion performance by the supercritical carbon dioxide (SCCO₂) foaming technology. As the cell structure determined the combustion properties of microcellular combustible objects, the solubility of SCCO₂ dissolved into the combustible objects was obtained from the gravimetric method, and scanning electron microscope (SEM) was applied to characterize the cell structure under various process conditions of solubility, foaming temperature and foaming time. SEM images indicate that the cell diameter of microcellular combustible objects is in the level of 1 μm and the cell density is about 10¹¹ cell⋅cm⁻³. The microcellular combustible objects fabricated by the SCCO₂ foaming technology are smooth and uniform, and the high specific surface area of cell structure can lead to the significant combustion performance of microcellular combustible object for CTA in the future.     

结合层次法与主成分分析特征变换的宫颈细胞识别

对宫颈细胞进行多分类可以自动识别出不同状态的细胞,进而为宫颈癌诊断提供科学依据。在用6种多分类算法进行实验后,选取支持向量机作为基分类器,先用一对一策略训练6个分类器进行3分类,然后再训练1个2分类器,这种二层4分类方法提高了识别准确率。考虑不同层特征模式的差异性,在保证识别性能的同时,每层分类前先采用主成分分析法将原始154维特征变换到低维空间,去除冗余特征,加快识别速度。实验证明,所提层次主成分分析法在宫颈细胞分类中相比6种传统多分类方法有更高的识别准确率,可达90%以上;识别速度也较普通层次法提升了21.31%。     

基于神经元的动态系统模糊关系模型及其学习算法

本文直接针对模糊集,提出了三种基于模糊集运算的逻辑神经元,即ＡＮＤ．ＯＲ和ＡＮＤ／ＤＲ．基于上述神经元,提出了一种应用于动态系统建模的实用的模糊关系网络模型,通过一个简单实例,证实了上述模型建模算法的学习能力和快速计算能力。     

Book reviews

Nuclear Non-Proliferation and Global Order. By Harald Muller, David Fischer, and Wolfgang Kotter. SIPRI, Oxford, Oxford University Press, (1994) ISBN 0-19-329155-8, hardback, £25.00

Conventional Arms Control: Perspectives on Verification By Sergey Koulik and Richard Kokoski, SIPRI, Oxford University Press, (1994) ISBN 0-19-829149-3 and

Implementing the Comprehensive Test Ban: New Aspects of Definition, Organisation and Verification Edited by Eric Arnett, SIPRI Research Report No. 8, Oxford University Press, (1994) ISBN 019-829188-4

Military Technological Innovation and Stability in a Changing World: Politically assessing and Influencing Weapons Innovation and Military Research and Development, By Wim A. Smit, John Grin and Lev Voronkov (eds.) VU University Press, Amsterdam, Netherlands (1992), ISBN 90-5383-158-4.

Security, democracy, and development in US - Latin American relations. By Lars Schoultz, William C. Smith and Augusto Varas (eds.) Transaction Publishers, New Brunswick (USA), and London (UK) (1994). ISBN 1-56000-760-5     

Book reviews

European Security in the New Political Environment by James H. Wyllie, London: Addison, Wesley Longman, 1997, ISBN 0-582-24403-X (pbk), £13.99

Russia and Europe: The Emerging Security Agenda edited by Vladimir Baranovsky, Oxford: Oxford University Press, SIPRI, 1997, ISBN 0-19-829201-5 (hbk), £45.00

The Defeat of Japan by David Rees, Westport, Connecticut and London: Praeger, ISBN 0-275-95955-4 (hbk), £46.50

The Collective Naval Defence of the Empire, 1900-1940 by Nicholas Tracy (ed.), London: Ashgate, for the Navy Records Society, 1997, ISBN 1859-284-027 (hbk), £59.50

Knights in White Armour The New Art of War and Peace by Christopher Bellamy, London: Pimlico Press, 1997, ISBN 0-7126-739-03 (pbk), £12.50

Regional Orders: Building Security in a New World by avid A. Lake and Patrick M. Morgan (eds), University Park: Penn State Press, 1997, ISBN 0-271-01703-i (hbk), £49.50/$55, ISBN 0-271-01704-X (pbk), £7.95/$19.95

Contested Social Orders and International Politics by David Skidmore (ed.), Nashville: Vanderbilt University Press, 1997, ISBN 0-8265-1284-4 (hbk), $32.95

The Politics of Threat: Minuteman Vulnerability in American National Security Policy by David H. Dunn. London: Macmillan Press, 1997, ISBN 0-333-67816-8 (hbk), £45.00

The Sociology of the Military by Guiseppe Caforio (ed.), Cheltenham: Edward Elgar, 1998, ISBN 1-85898-619-2, 704 pp., £150

The Nordic Nations in the New Western Security Regime by Ingemar Dorfer, Baltimore: Johns Hopkins University Press, 1997, ISBN 0-943875-83-8 (hbk), £27, ISBN 0-943875-82-X (pbk), £13     

More on the search for an infiltrator

We have asymptotically solved a discrete search game on an array of n ordered cells with two players: infiltrator (hider) and searcher, when the probability of survival approaches 1. The infiltrator wishes to reach the last cell in finite time, and the searcher has to defend that cell. When the players occupy the same cell, the searcher captures the infiltrator with probability 1 ? z. The payoff to the hider is the probability that the hider reaches the last cell without getting captured. © 2002 John Wiley & Sons, Inc. Naval Research Logistics, 49: 1–14, 2002; DOI 10.1002/nav.1047     

Book reviews

Use of Force: The Practise of States by A. Mark Weisburd, Penn: Penn State Press, University Park, 1997, ISBN 0-271-01679-5 (hbk), $65.00/£58.00, ISBN 0-271-01680-9 (pbk), $25.00/£22.50

Late Breaking Foreign Policy: the News Media's Influence on Peace Operations by Warren P. Strobel, Washington DC: United States Insititute of Peace Press, 1997, ISBN 1-878379-68-2 (hbk), £23.25, ISBN 1-878379-67-4 (pbk)

The Reluctant Sheriff: The United States After the Cold War by Richard N. Haass, New York: Council on Foreign Relations, 1997, 148pp, index, ISBN 0-87609-201-6 (hbk), $24.95

The UN, Peace and Force edited by Michael Pugh, London: Frank Cass, 1997, ISBN 0-7146-4795-4 (hbk), £29.50, ISBN 0-7146-4320-3 (pbk), £15.00

Confidence-Building in South East Asia by Malcolm Chalmers, Oxford: Westview Press, 1996, ISBN 1-85143-116-0 (pbk), £19.95

Britain's Strategic Nuclear Deterrent: From Before the V-Bomber to Beyond Trident by Robert H. Paterson, London: Frank Cass, 1997, ISBN 0-7146470-3 (hbk), £35.00, ISBN 0-7146-4297-5 (pbk) £18.00

OSS in China: Prelude to Cold War by Maochun Yu, London: Yale University Press, 1997, ISBN 0 300 06698-8 (hbk), £25.00

Preventing Violent Conflicts: A Strategy for Preventive Diplomacy by Michael S. Lund, Washington DC: US Institute of Peace Press, 1996, ISBN 1-878379-52-6 (pbk), £11.75     

Book reviews

War, Culture and the Media: Representations of the Military in 20th Century Britain. Edited by Ian Stewart and Susan L. Carruthers, Trowbridge: Flicks Books, (1996), ISBN 0-948911-86-7 (pbk), £14.95.

The Future of Europe. By Peter Coffey, Aldershot: Edward Elgar, (1995), ISBN 1-85278-586-1 (hardback), £39.95, ISBN 1-85278-587-X (pbk), £12.95.

Global Dangers: Changing Dimensions of International Security. Edited by Sean M. Lynn-Jones, Steven E. Miller, London: the MIT Press, (1996), ISBN O-262-62097-9 (pbk), £13.50;.

New Studies in Post-Cold War Security. Edited by K.R. Dark, Aldershot: Dartmouth Publishing Company, (1996), ISBN 1-85521-728-7 (hardback), £42.50.

Enlarging NATO - The Russian Factor. By Richard L. Kugler with Marianna V. Kozintseva, Santa Monica, CA: National Defense Research Institute and Rand Corporation, (1996), ISBN 0-8330-2357-8, $20.00.     

On the (S − 1, S) lost sales inventory model with priority demand classes

In this paper an inventory model with several demand classes, prioritised according to importance, is analysed. We consider a lot‐for‐lot or (S ? 1, S) inventory model with lost sales. For each demand class there is a critical stock level at and below which demand from that class is not satisfied from stock on hand. In this way stock is retained to meet demand from higher priority demand classes. A set of such critical levels determines the stocking policy. For Poisson demand and a generally distributed lead time, we derive expressions for the service levels for each demand class and the average total cost per unit time. Efficient solution methods for obtaining optimal policies, with and without service level constraints, are presented. Numerical experiments in which the solution methods are tested demonstrate that significant cost reductions can be achieved by distinguishing between demand classes. © 2002 Wiley Periodicals, Inc. Naval Research Logistics 49: 593–610, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/nav.10032     

基于ADS的仿真体系结构及其在EW靶场的应用

给出了组合LVC资源的ADS系统的基本概念，提出了可以适应LVC资源综合利用的层次式仿真体系结构。在总结电子战仿真系统开发过程的基础上，确定了将来自靶场暗室和外场资源真实的试验数据投入到ADS中采用的过程和方法。仿真系统的试验应用表明该体系结构能够充分利用各种资源的优势，满足电子战系统的试验训练需求。