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161.
Claims that China is the only nuclear power currently expanding its arsenal fail to take into account the technical, historical, and bureaucratic realities that shaped China's nuclear posture and drive its ongoing modernization. China's strategic modernization is largely a process of deploying new delivery systems, not designing new nuclear warheads; the majority of its new missiles are conventionally armed. Today, China maintains the smallest operationally deployed nuclear force of any of the legally recognized nuclear weapon states, operates under a no-first-use pledge, and keeps its warheads off alert. The modernization of China's delivery systems is the culmination of a decades-long plan to acquire the same capabilities deployed by the other nuclear powers. U.S. concerns about this modernization focus too much on deterring a deliberate Chinese attack and ignore the risk that modernized U.S. and Chinese forces could interact in unexpected ways during a crisis, creating uncontrollable escalatory pressures. To manage this risk, Washington should assure Chinese leaders that it does not seek to deny China's deterrent, in exchange for some understanding that China will not seek numerical parity with U.S. nuclear forces.  相似文献   
162.
Britain underestimated the importance of the naval mine in the years leading up to the First World War and entered the conflict unprepared for an extended mine campaign. Traditional interpretations of the mine's position are limited and neglect the broader political and economic factors influencing its development. The mine was a peripheral technology representative of the rapid technological change in the period, and its development was affected by financial constraints, international diplomacy and naval administration. Because of structural impediments, however, and despite significant resources devoted to the weapon, the mine faced obstacles which led to both limited stocks and inadequate plans for use at the opening of the First World War.  相似文献   
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SOE in France: An Account of the Work of the Special Operations Executive in France 1940-1944. By M. R. D. FOOT. Her Majesty' Stationary Office, London, 550 pp., 1966. Second impression with amendments 1986.  相似文献   
165.
In recent years, some attention has been devoted to the application of techniques of control theory to inventory management. In particular, H. Vassian (1955) developed a model for a periodic review inventory system utilizing techniques of discrete variable servomechanisms to analyze the system in a cost-free structure. The resulting model is inherently deterministic, however, and emphasizes the control of inventory fluctuation about a safety level by selecting an appropriate order policy. Such an order policy is defined only up to an arbitrary method of forecasting customer demands. The present paper is a continuation of the model developed by Vassian in which exponential smoothing is used as a specific forecasting technique. Full recognition of the probabilistic nature of demand is taken into account and the requirement of minimizing expected inventory level is imposed. In addition, explicit formulas for the variance in inventory are derived as functions of the smoothing constant and the tradeoff between small variance and rapid system response is noted. Finally, in an attempt to remove the bias inherent in exponential smoothing, a modification of that technique is defined and discussed as an alternate forecasting method.  相似文献   
166.
Recent research has led to several surrogate multiplier search procedures for use in a primal branch-and-bound procedure. As single constrained integer programming problems, the surrogate subproblems are also solved via branch-and-bound. This paper develops the inner play between the surrogate subproblem and the primal branch-and-bound trees which can be exploited to produce a number of computational efficiencies. Most important is a restarting procedure which precludes the need to solve numerous surrogate subproblems at each node of a primal branch-and-bound tree. Empirical evidence suggests that this procedure greatly reduces total computation time.  相似文献   
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Several problems in the assignment of parallel redundant components to systems composed of elements subject to failure are considered. In each case the problem is to make an assignment which maximizes the system reliability subject to system constraints. Three distinct problems; are treated. The first is the classical problem of maximizing system reliability under total cost or weight constraints when components are subject to a single type of failure. The second problem deals with components which are subject to two types of failure and minimizes the probability of one mode of system failure subject to a constraint on the probability of the other mode of system failure. The third problem deals with components which may either fail to operate or may operate prematurely. System reliability is maximized subject to a constraint ori system safety. In each case the problem is formulated as an integer linear program. This has an advantage over alternative dynamic programming formulations in that standard algorithms may be employed to obtain numerical results.  相似文献   
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