Uncertainties in building a strategic defense

Building a strategic defense against nuclear ballistic missiles involves complex and uncertain functional, spatial, and temporal relations. Such a defensive system would evolve and grow over decades. It is too complex, dynamic, and interactive to be fully understood initially by design, analysis, and experiments. Uncertainties exist in the formulation of requirements and in the research and design of a defense architecture that can be implemented incrementally and be fully tested to operate reliably. The analysis and measurement of system survivability, performance, and cost-effectiveness are critical to this process. Similar complexities exist for an adversary's system that would suppress or use countermeasures against a missile defense. Problems and opportunities posed by these relations are described, with emphasis on the unique characteristics and vulnerabilities of space-based systems.     

Carter's Plan for MX Lives On

Early this year, the U.S. land-based force of nuclear missiles became vulnerable-on paper-to destruction in a preemptive attack by the Soviet Union. The Air Force has worried about this problem for a long time, searching high and low for a better place to put both the existing, silo-based Minuteman missiles and a new missile, the MX. Under the Carter Admnistration, the Air Force agreed to a missle basing plan known as MPS, for multiple protective shelters. The Reagan Administration has ostensibly dropped this plan in favour of several alternatives. Previous articles in this series explored why U.S. officials became alarmed about missile vulnerability; the genesis of a short-term plan to put more missiles into silos; continuing Air Force opposition to a plan for missiles on constantly roving aricraft; and a bizare plan to bury missiles deep underground.     

Air force takes aim at a big bird

Early this year, the U.S. land-based force of nuclear missiles became vulnerable to destruction in a preemptive attack by the Soviet Union. The Air Force has worried about this situation for a long time, searching high and low for a better place to put both the existing silo-based missiles and a new missile, the MX. The first article in this series examined the reasons that U.S. officials became alarmed about missile vulberability, and the second examined the short-term plan to put missiles into silos. This article explores the Ait Force's least favourite long-term basing mode. Subsequent articles will explore the alternatives.     

An upheaval in u.s. Strategic thought

Early this year, the U.S. land-based force of nuclear missiles became vulnerable to a preemptive attack by the Soviet Union, as the Soviets deployed a large number of highly accurate warheads on their own missiles. They first demonstrated this capability in 1977. Since then, U.S. missile vulnerability has come to assume great importance in superpower relations. Western observers have portrayed the Soviet achievement as a sign of aggression, and made missile vulnerability into a symbol of declining American military strength. The government has proposed a vast military buildup of nuclear weapons, supposedly made necessary by this new threat. But the public is increasingly skeptical, and support for some form of arms control is growing. The first article in this series examines how the United States learned of the Soviet accuracy, and why it caused such great alarm. The next article will examine the Reagan Administration's response to this threat.     

海洋捕捞渔船用生物柴油减排的成本-效益分析

海洋捕捞业是我国渔业能耗和CO2排放的主要领域,捕捞渔船的节能减排水平低,潜力大。总结了我国海洋捕捞渔船能耗及排放现状,分析了生物柴油的特性及作为渔船代用燃料的优缺点,根据海洋捕捞渔船动力装置的特点提出了掺混生物柴油需对柴油机做出的改进措施,对捕捞渔船柴油机掺混5%体积分数的生物柴油的节能减排效果进行了成本-效益分析。结果显示,海洋捕捞渔船柴油机掺混5%的生物柴油将导致每船每年平均减少1 371元左右的燃料费用和2 000元左右的维修费用,但需付出较高的船舶改造成本;若我国所有的海洋捕捞渔船柴油机都添加5%的生物柴油,每年会降低二氧化碳排放近13.4万吨,按目前国际上的碳交易价格计算,每年将产生400多万元的社会环境效益。生物柴油具有一定的经济优势,环保性能显著,具有良好的减排效果,可以促进我国海洋捕捞渔船的节能减排和国家减排目标的实施。     

Dispelling myths about verification of sea-launched cruise missiles

It is widely believed that an arms control limit on nuclear-armed sea-launched cruise missiles would be nearly impossible to verify. Among the reasons usually given are: these weapons are small, built in nondistinctive industrial facilities, deployed on a variety of ships and submarines, and difficult to distinguish from their conventionally armed counterparts. In this article, it is argued that the covert production and deployment of nuclear-armed sealaunched cruise missiles would not be so straightforward. A specific arms control proposal is described, namely a total ban on nuclear-armed sea-launched cruise missiles. This proposal is used to illustrate how an effective verification scheme might be constructed.     

公共服务合同外包中的交易成本及其控制

公共服务合同外包作为一项交易，不可避免地存在不少交易成本变量,公共服务合同外包不一定能降低交易成本、公共服务合同外包中存在不确定性成本、公共服务合同外包难以合理界定交易成本等都是这些变量的体现。基于这些交易成本变量，大胆而细致地选择公共服务合同外包，建立公共服务合同外包风险防范机制，建立较为公平、合理的风险分担机制，提高政府对公共服务合同外包的控制能力等应是降低公共服务合同外包交易成本的可行路径。     

The economics of resource recovery from municipal solid waste

A prototypical operating statement similar to that used by business firms has been shown to be a useful decision-making tool for a community choosing a solid waste management system. When applied to resource recovery, it highlights the economics of recovery and the values of the input parameters necessary to achieve economic viability, whether in the case of public or private ownership (23). In most communities, refuse processing to recover material resources must be based on more than one source of revenue. In addition to the revenues from the sale of by-products, there must be revenues from processing the incoming refuse and from a user, or dump, fee. In the first case discussed, that of materials recovery by a front end system, resource recovery is shown to be economically feasible for those communities in which the present cost of disposal is relatively high. The indifferent community was one having a current cost of $7.72 per ton; more accurately, this would be the cost for the near-term future. It is not necessary that current costs be used, since many communities are merely "dumping" their refuse. The indifference decision should be based on the cost of an environmentally sound alternative. Energy recovery from municipal solid waste can increase the number of communities in which resource recovery will be an economic adjunct to a solid waste management system. The analysis presented here was based on the assumption that the value of the fuel recovered exactly offset the additional capital and operating costs of the utility which burns it. There could be costs above and beyond this; similarly, there could be a saving by taking into account the economic value of the organic fraction as fuel. However, it is believed that the assumption under which the materials-plus-energy case was analyzed seems to be realistic at this time.     

日光温室土墙厚度的优化——以杨凌地区为例

为减少日光温室土质墙体成本并满足作物生长,对后墙厚度进行优化。以单位造价的节能量为日光温室节能改造的技术经济评价指标,分析日光温室土墙系统在节能工程中的成本构成;通过分析日光温室的状态系数、墙体传热系数和不变成本,着重研究节能量和土墙厚度的关系。研究结果表明:在杨凌地区,当不变成本为43.08元/m2,单位造价节能量取极大值时,增加厚度为1.18m,实际建造厚度为2.30m。引入性价比将墙体技术参数和经济参数有效连系起来,以杨凌地区为例,得到了日光温室土墙增加厚度优化式。     

Space-based radar

The concept of national air defense against aircraft and cruise missiles has been evolving in parallel with the Strategic Defense Initiative and is being referred to as the Air Defense Initiative. One of the most promising sensor concepts for the Air Defense Initiative is space-based radar. Operated at microwave frequencies as an instrument for wide-area surveillance, space-based radar may be useful in mission areas such as fleet defense and battlefield surveillance.     

激光光致发光光谱分析系统的设计及应用

在微区紫外-可见阴极荧光分析系统成功研制的基础上,采用532nm固体激光器作为激发源研制了一套计算机自动控制的微区光致发光分析系统。该系统不仅可探测可见波段的激光光致荧光,并且将荧光的研究波段扩展至红外区域。对来自于不同地区金刚石样品的900～1010nm波段红外光致发光光谱进行探测,结果发现不同样品在946nm、957nm左右2个宽峰处呈现不同光谱特征,能有效地对样品的生长条件和受外界影响等因素进行分析和研究。该分析系统能在更宽的波段上获取更多更新的样品内在信息,为样品的测试提供了一种有效方法。     

Missile Defense: LBJ's Bid To Curb Arms Race Gains Support

In the article of 31 March on antiballistic missile defense, the last sentence of paragraph 2, p. 1654, should read: "Manpower for producing . . . but the outer limit would be about 200,000, or half the number of contractor employees and civil servants working for NASA at the peak of the Apollo program."     

考虑系统性与时变性的交通事故风险成本模型

针对交通事故风险成本计算方法需考虑交通事故风险的系统性与时变性,利用结构模型分析交通安全系统各要素间的相互关系及其影响,构建了交通事故风险成本计算模型.以车辆要素为建模的关键,通过聚类分析方法建立交通事故风险的基本模型.以连续行驶时间、车速、道路转弯半径、道路纵坡以及天气等参数为动态影响因素,结合广义成本理论,建立适用于各出行方式的交通事故风险成本模型.以珠海市某一级公路的实际调查数据作为算例,探讨交通事故风险成本模型的应用.算例结果表明:不同出行方式的交通事故风险成本差异较大,合理选择交通出行方式可有效降低交通事故风险成本及出行成本,该模型能够兼顾交通事故风险的系统性与时变性,更加符合客观实际,具有较好的合理性.     

城市可持续发展的经济成本分析——以贵阳市为例

在对城市化经济成本构成进行辨识的基础上,从就业岗位投资成本、城市化用地投资成本、城市化基础设施投资成本和城市化管理投资成本4个方面构建了城市化经济成本计量模型。在此基础上以贵阳市为例,测算出当前的社会经济发展水平下贵阳市每增加一个城市化人口需要经济成本,并对未来10年贵阳城市发展的资金需求进行预测,指出贵阳未来可持续发展与城市化进程将面临明显的资金缺口,旨在能为未来城市可持续发展的速度和合理目标提供依据。     

MILITARY RESEARCH: Researchers Target Flaws in Ballistic Missile Defense Plan

More than three dozen scientists journeyed to Washington, D.C., this week to warn lawmakers that a proposed $60 billion U.S. missile defense system, designed to knock incoming warheads out of the sky, is technically flawed because it can't pick out real warheads from decoys. Pentagon officials heatedly deny a new report by one scientist that contractors have rigged trials to hide the problem, although they admit that some tests were simplified to save time. In the wake of these events, a leading Democrat is urging President Bill Clinton to delay a pending decision on building the system.     

Technology Creep and the Arms Race: ICBM Problem a Sleeper

In three articles, Science will discuss how the creep of technology affects the arms race. The first two articles will deal with the most important current example: first, how ICBM modernization is giving both sides a destabilizing, first-strike capability, and second, how arms control seems to be dealing inadequately with this pressing problem. The third article will describe other cases of incremental technical improvements affecting arms control, such as antisatellite research and ballistic missile defense research, which are bringing both sides closer to the antiballistic missile capability they forswore in a 1972 treaty.     

固定顶油罐泡沫灭火系统的改进方法

针对固定顶油罐现有的3种泡沫灭火系统的缺陷,设计了一种新型泡沫灭火系统。该系统克服了液上泡沫灭火系统容易遭到破坏且效率不高、液下泡沫灭火系统容易污染油液并需要高压泵及半液下泡沫灭火系统不能重复使用和造价较高的不足。系统主要由软管、空心浮子、十字喷嘴和泄压管组成,造价低廉,灭火效率高,使用和维护成本低,性价比高,有较高的推广价值。     

Evolution and immunology. The economics of immunity

Our vigilant immune systems are ready to mount an attack as soon as an invading pathogen is spotted. But what is the cost of keeping this sophisticated defense system on red alert? In a provocative Perspective, Read and Allen discuss new findings showing that the cost of immune defense in animals is very high (Moret and Schmid-Hempel), and the claim that, in some circumstances, the cost may be worth the benefit gained (Nunn et al.).     

News of Science

On page 925 of the 9 Nov. issue of Science we stated that "Nineteen members of the Atomic Energy Commission research project at the University of Rochester Medical Center" endorsed a statement criticizing the President's recent defense of nuclear weapons tests. Actually, only five of the 19 members of the university staff who signed the statement were associated with the AEC project. These five constituted about 10 percent of the project's scientific staff.     

并行测试技术工程化应用研究

并行测试技术在测试系统中应用越来越广,采用并行测试技术能够提高系统的测试效率和性价比。本文提出了几种并行测试结构形式,并结合实际测试需求进行某型号导弹测试的并行测试分析与实践,详细分析了某型导弹开展并行测试的可行性及实施方法,最终选择多个被测对象并行测试的方法;通过并行测试,减少了测试时间,提高了测试速度,使该型导弹的测试效率提高了50%以上,可有效提高装备使用效率,具有一定的工程实践意义。