横滚输出残差的X字舵航行器故障检测

首先介绍了X字舵航行器的执行机构硬故障对运行状态的影响,然后基于其在横滚通道的稳定性,重点研究了一种适用于多弹道的残差构造形式来检测这种故障.最后通过建立鱼雷动力学、运行学模型和模拟故障模型,验证了残差格式的有效性.这为构建X字舵航行器故障综合诊断重构系统完成了重要一环.     

夯实标准化管理基础 努力提高兵器民爆竞争力

通过介绍兵器集团公司对民爆器材行业的管理体系、渠道和方式,探讨集团对民爆器材的标准化管理模式。     

基于截断函数的有限时间滑模控制方法

针对一类二阶不确定非线性系统的鲁棒控制问题,提出一种基于截断函数的有限时间滑模控制算法。该算法具有以下特点:系统状态可在期望的有限时刻收敛为零;受控系统对外部扰动和参数不确定性具有全局鲁棒特性;系统状态的动态响应可解析预测;通过选择不同的截断函数可以实现对控制器性能的调节。仿真结果验证了所提算法的有效性。     

Aggregating courier deliveries

We consider the problem of efficiently scheduling deliveries by an uncapacitated courier from a central location under online arrivals. We consider both adversary‐controlled and Poisson arrival processes. In the adversarial setting we provide a randomized (3βΔ/2δ ? 1) ‐competitive algorithm, where β is the approximation ratio of the traveling salesman problem, δ is the minimum distance between the central location and any customer, and Δ is the length of the optimal traveling salesman tour overall customer locations and the central location. We provide instances showing that this analysis is tight. We also prove a 1 + 0.271Δ/δ lower‐bound on the competitive ratio of any algorithm in this setting. In the Poisson setting, we relax our assumption of deterministic travel times by assuming that travel times are distributed with a mean equal to the excursion length. We prove that optimal policies in this setting follow a threshold structure and describe this structure. For the half‐line metric space we bound the performance of the randomized algorithm in the Poisson setting, and show through numerical experiments that the performance of the algorithm is often much better than this bound.     

The Economic Effect of Military Facility Contraction: A Naval Case Study

The global financial turmoil of 2008 has resulted in the curtailment of military expenditure in most western countries. At a sub-regional-level reductions in the level of activity at a major military facility can have significant economic impact. In the light of this, the paper has two objectives: to analyse the impact of the decision to terminate naval shipbuilding at the United Kingdom’s Portsmouth Naval Base; and, for illustrative purposes, to examine the possible economic consequences of further contraction at the facility. In pursuit of these aims, it is necessary to establish the output, income and employment generated by the base using a bespoke input–output model. The methodology employed can, with appropriate adjustments, be utilised in other military or civilian contexts.     

Minimization of expected variance of completion times on single machine for stochastic jobs

This article deals with the problem of scheduling jobs with random processing times on single machine in order to minimize the expected variance of job completion times. Sufficient conditions for the existence of V-shaped optimal sequences are derived separately for general and ordered job processing times. It is shown that when coefficient of variation of random processing times are bounded by a certain value, an optimal sequence is V-shaped. © 1997 John Wiley & Sons, Inc.     

Average-case analysis of the bin-packing problem with general cost structures

We consider a version of the famous bin-packing problem where the cost of a bin is a concave function of the number of items in the bin. We analyze the problem from an average-case point of view and develop techniques to determine the asymptotic optimal solution value for a variety of functions. We also describe heuristic techniques that are asymptotically optimal. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 673–686, 1997     

Balancing stability and efficiency in team formation as a generalized roommate problem

The assignment of personnel to teams is a fundamental managerial function typically involving several objectives and a variety of idiosyncratic practical constraints. Despite the prevalence of this task in practice, the process is seldom approached as an optimization problem over the reported preferences of all agents. This is due in part to the underlying computational complexity that occurs when intra-team interpersonal interactions are taken into consideration, and also due to game-theoretic considerations, when those taking part in the process are self-interested agents. Variants of this fundamental decision problem arise in a number of settings, including, for example, human resources and project management, military platooning, ride sharing, data clustering, and in assigning students to group projects. In this article, we study an analytical approach to “team formation” focused on the interplay between two of the most common objectives considered in the related literature: economic efficiency (i.e., the maximization of social welfare) and game-theoretic stability (e.g., finding a core solution when one exists). With a weighted objective across these two goals, the problem is modeled as a bi-level binary optimization problem, and transformed into a single-level, exponentially sized binary integer program. We then devise a branch-cut-and-price algorithm and demonstrate its efficacy through an extensive set of simulations, with favorable comparisons to other algorithms from the literature.     

CFO条件下的OFDM子载波调制样式识别方法

提出了一种基于信号幅度分布特征与多次方谱线特征相结合的调制样式识别算法。该算法主要基于正交解调后的正交频分复用子载波信号的幅度分布特征,采用直方图统计的方法实现多进制相移键控和多进制正交幅度调制识别,用多方次谱特征实现多进制相移键控类的调制识别。相比基于经典的高阶累积量的调制识别算法,具有更好的载波频率残留偏差适应能力,在载波频率偏差条件下,提高了调制识别率;相比循环平稳方法,具有更好的信噪比适应能力。仿真实验结果表明了该方法的有效性,相同的识别率下能适应更低的信噪比。