改进的基于迭代算法的Weibull分布杂波模拟方法

杂波在雷达环境模拟中具有非常重要的地位.基于ZMNL(无记忆非线性变换法)的Weibull分布雷达杂波模型,可以很好地描述海杂波.但这种模型,因其非线性变换前后相关系数之间的关系公式复杂,很难用直观的方法求解.针对这一问题,提出了用迭代算法来求解该非线性公式的过程,并给出了应用该方法进行杂波仿真的具体步骤及仿真结果,证明了该方法的准确、可行性.     

Scheduling with centralized and decentralized batching policies in concurrent open shops

This article considers batch scheduling with centralized and decentralized decisions. The context of our study is concurrent open shop scheduling where the jobs are to be processed on a set of independent dedicated machines, which process designated operations of the jobs in batches. The batching policy across the machines can be centralized or decentralized. We study such scheduling problems with the objectives of minimizing the maximum lateness, weighted number of tardy jobs, and total weighted completion time, when the job sequence is determined in advance. We present polynomial time dynamic programming algorithms for some cases of these problems and pseudo‐polynomial time algorithms for some problems that are NP‐hard in the ordinary sense. © 2010 Wiley Periodicals, Inc. Naval Research Logistics 58: 17–27, 2011     

Properties of a mean residual life function arising from renewal theory

The present article discusses the properties of the mean residual life function in a renewal process. We examine the relationship this function has with the failure rate function and the conventional mean, variance and coefficient of variation of residual life. We also discuss some monotonicity properties of the mean residual life function. A partial order based on the renewal mean residual function is introduced along with its interrelationship with some existing stochastic orders. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010     

Estimation from binomial data with classifiers of known and unknown imperfections

Observations from inspection by a “test” method and a standard method are combined to provide estimators of population proportion, and of probabilities of misclassification for the test method. Results of Hochberg and Tenenbein [3] and of Albers and Veldman [1] are extended to the case where the standard method is not perfect, but its misclassification probabilities have known values. Both moment and maximum-likelihood estimators are considered and some asymptotic properties of the resulting estimators are compared.     

Rising bipolarity in the South China Sea: the American rebalance to Asia and China's expansion

This article synthesizes three elements of power and balancing in the South China Sea (SCS): analytical perspectives on China's behaviour and intentions, the American rebalance to Asia and the dispositions of American allies and partners. Based on extensive interviews and theoretical analysis, it concludes that ‘soft balancing’ backed by American military power provides the optimum chance for resolving the growing dispute. Short to medium-term weakness of Malaysia, Philippines and Vietnam, as well as Japan, means the United States must provide much of the military power while working to build their forces. The most promising alternative is multilateral diplomacy through the Association of Southeast Asian Nations’ Regional Forum, a vehicle for negotiating a Code of Conduct and implementation of the UN Convention on the Law of the Sea. If China remains motivated mainly by defense of realist interests, the costs imposed against expansion will eventually cause recalculation of Beijing's strategy, and soft balancing by the United States and its partners has a chance of working. The constructivist perspective, stressing self-conceptualization of Chinese strategic culture, supports Chinese confidence that patience will eventually bring dominance. If China tries offensively to change the status quo, soft balancing is less likely to influence Beijing. President Xi Jin Ping appears to be offensively asserting power, seeking regional dominance before he is due to step down in 2023. This supports the finding of enhanced risks of unintended escalation in the SCS and the East China Sea.     

Remotely Piloted Aircraft,Risk, and Killing as Sacrifice: The Cost of Remote Warfare

In this paper I argue that a remotely piloted aircraft (RPA) pilot’s act of killing remotely, when it is done in the defense of another person, can be viewed as an act of sacrifice. This argument concludes from two premises. First, the RPA pilot faces psychological risk to self by carrying out such an action; second, the RPA pilot is motivated to some significant degree by something other than self-interest. Moreover, I challenge both the view that RPA represent merely an incremental development in technology yielding an incremental expansion of the distance between the war-fighter and the target and the view that RPA is revolutionary in some fundamental sense. I instead argue that, based upon the natural geometric boundary imposed by the earth’s shape, RPA have maximized the physical distance between the war-fighter and the target and, over time, this fact will change, not only the psychological effects on the RPA pilot, but also the way we view killing and distance in general. When taken together, these two broad claims, that other-defense can justify killing in war and that there is a psychological cost paid by remote killers, yield a conception of remote killing as an act of sacrifice that will inform the broader conversation about ethics, risk, killing, and RPA.     

Algorithms for the design of finite-capacity service units

Finite-capacity queues arise naturally in many practical situations, notably in communications and manufacturing engineering. In this article, the matrix formalism of probability distributions of phase type is used to develop fast algorithms to compute various steady-state distributions for the finite-capacity PH/PH/1 queue. This algorithm is an important ingredient in solving nontraditional but significant design problems. Some of these are described as illustrative examples.     

Effects of lethality in naval combat models

In the context of both discrete time salvo models and continuous time Lanchester models we examine the effect on naval combat of lethality: that is, the relative balance between the offensive and defensive attributes of the units involved. We define three distinct levels of lethality and describe the distinguishing features of combat for each level. We discuss the implications of these characteristics for naval decision‐makers; in particular, we show that the usefulness of the intuitive concept “more is better” varies greatly depending on the lethality level. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004.     

The fractional fixed-charge problem

Fractional fixed-charge problems arise in numerous applications, where the measure of economic performance is the time rate of earnings or profit (equivalent to an interest rate on capital investment). This paper treats the fractional objective function, after suitable transformation, as a linear parametric fixed-charge problem. It is proved, with wider generality than in the case of Hirsch and Dantzig, that some optimal solution to the generalized linear fixed-charge problem is an extreme point of the polyhedral set defined by the constraints. Furthermore, it is shown that the optimum of the generalized fractional fixed-charge problem is also a vertex of this set. The proof utilizes a suitable penalty function yielding an upper bound on the optimal value of the objective function; this is particularly useful when considering combinations of independent transportation-type networks. Finally, it is shown that the solution of a fractional fixed-charge problem is obtainable through that of a certain linear fixed-charge one.