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41.
Brian Johnson, The Secret War. London: BBC, 1978. Pp. 352; £6.50.

R. V. Jones, Most Secret War: British Scientific Intelligence 1939–45. London: Hamish Hamilton, 1978. Pp. xx + 556; £7.95.

Solly Zuckerman, From Apes to Warlords 1904–46. London: Hamish Hamilton, 1978. Pp. 00 (Information not available from publisher); £8.50.

Adrian Preston, ed., General Staffs and Diplomacy before the Second War. London: Croom Helm, 1978. Pp. 138; £5.95.

W. G. F. Jackson. ’Overlord’: Normandy 1944. London: Davis Poynter, 1978. Pp. 250; £6.75.

Richard K. Betts, Soldiers, Statesmen, and Cold War Crises. Cambridge, Mass. and London: Harvard University Press, 1977. Pp. 292 + index + appendices; Np.

Gerard J. Mangone, Marine policy for America—The United States at Sea. Lexington, Mass.: Lexington Books, 1977. Pp. 370, £17.50.

F. M. Richardson, Fighting Spirit. London: Leo Cooper, 1978. Pp. 189 + xv; £7.50.

Allen R. Millet, Ed., A Short History of the Vietnam War. London &; Bloomington: Indiana University Press, 1978. Pp. 169; £2.75.

Robert P. Berman, Soviet Airpower in Transition. Washington: Brookings, 1978. Pp. 82; $2.95 (Paper).  相似文献   
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By running life tests at higher stress levels than normal operating conditions, accelerated life testing (ALT) quickly yields information on the lifetime distribution of a test unit. The lifetime at the design stress is then estimated through extrapolation using a regression model. In constant‐stress testing, a unit is tested at a fixed stress level until failure or the termination time point of test, whereas step‐stress testing allows the experimenter to gradually increase the stress levels at some prefixed time points during the test. In this work, the optimal k‐level constant‐stress and step‐stress ALTs are compared for the exponential failure data under complete sampling and Type‐I censoring. The objective is to quantify the advantage of using the step‐stress testing relative to the constant‐stress one. Assuming a log‐linear life–stress relationship with the cumulative exposure model for the effect of changing stress in step‐stress testing, the optimal design points are determined under C/D/A‐optimality criteria. The efficiency of step‐stress testing to constant‐stress one is then discussed in terms of the ratio of optimal objective functions based on the information matrix. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 00: 000–000, 2013  相似文献   
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The Pakistani Taliban, factionalized into some 40 groups, form a decentralized insurgent movement, often characterized by infighting, divergent motivations, and a shifting web of alliances. The Pakistani Taliban remain little understood because most scholars have avoided a serious treatment of the insurgent movement and instead focused on analyzing the geopolitics of the region and Pakistan's ‘double game’. This article seeks to fill this gap by dissecting the movement through selected theories of organization and mobilization. First, I explain the various dimensions of the conflict and the origins of the insurgency. Next, I discuss the Pakistani Taliban's political organization, categorizing it as composed of various warlord regimes. I further list the Taliban's component groups and numerical strength and chart the leadership structure. Lastly, I analyze insurgent recruitment strategies, accounting for the role of selective incentives, coercion, and genuine grievances.  相似文献   
46.

Given the challenges posed by failed and failing states, and the likelihood that such failure will continue well into the new millennium, the need for a strategic approach appears evident. Should we respond? If so, how and with what expectations? Answers to such questions require an underlying set of strategic guidelines. This article contributes to developing that strategy by examining common manifestations of state failure and some possible response objectives. It concludes by arguing that careful and tough analysis must guide our choices about where and when to respond, and how ambitiously we set our objectives.  相似文献   
47.
This paper provides a framework in which warranty policies for non-repairable items can be evaluated according to risk preferences of both buyers and sellers. In particular, a warranty price schedule is established such that sellers are indifferent among the policies. Given this schedule, a buyer's response is expressed by selecting the price-warranty combination that minimizes disutility. Within this framework, a warranty can be viewed as an instrumet of risk management that can induce more sales and greater profitability. For given utility functions, analytical results for the development of a price schedule are developed. Numerical results illustrate the substitution effects between warranty terms, prices, and risk parameters.  相似文献   
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作者在前面的文章中报导了扭轮摩擦传动能实现亚纳米级的定位分辨率。然而,这套装置在结构上的复杂之处就是在于采用了静压轴承支撑扭轮。本文指出了扭轮摩擦传动在结构上如何可以简化为采用球轴承支撑扭轮。在简化之后,实验表明定位分辨率小于1纳米。本文得出结论,采用球轴承的扭轮摩擦传动对于在洁净环境下要求实现纳米级定位的制造过程变得更为方便,而且可以取代滚珠丝杠以及常规摩擦传动方式。  相似文献   
50.
L.Chouanine  H.Eda  M.li  雍玲 《国防科技》1997,18(3):94-98
本文讲述了由PC机控制的多用途超精机床(MPUMT)的设计及光学镜平滑表面的加工。已研制出的机床可用于磨削、切削、研磨或抛光塑性状态下的硬脆材料。作为建立新的加工系统的关键部分,采用了大型磁致伸缩调节器(GMA),在没有放大器元件的情况下,它具有大功率的输出和大于压电陶瓷调节器几倍的纳米级的位移。切削DOC的深度和控制塑性状态过程的微塑性区域能够被调节器设置为具有高于1nm的精度,并能用金刚石磨削砂轮研磨。在当前研究中所用到的镜为多晶体、非晶体,也有加固玻璃。磨削实验的结果表明,已研制出来的超精机床能够实现对塑性状态下的玻璃和陶瓷材料的加工。材料特性参数和微裂纹之间的关系已被检测到,适用于大多数被研究玻璃的脆性到塑性磨削方式的转换已经确定。运用AFM、SEM和ZYGO对磨削表面进行了分析,例如BK7和TRC5(新材料;加固玻璃)的磨削表面分别具Ra=0.15nm和Ra=0.32nm的表面粗糙度。  相似文献   
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