基于Petri网的C2S性能分析方法研究

给出了用时间连续随机Petri网和时间离散随机Petri网计算系统稳态概率的方法,并将其应用于指挥控制系统(C2S)的性能分析中,分析结果表明这种计算方法是可行的。     

Response surface analysis of two‐stage stochastic linear programming with recourse

We apply the techniques of response surface methodology (RSM) to approximate the objective function of a two‐stage stochastic linear program with recourse. In particular, the objective function is estimated, in the region of optimality, by a quadratic function of the first‐stage decision variables. The resulting response surface can provide valuable modeling insight, such as directions of minimum and maximum sensitivity to changes in the first‐stage variables. Latin hypercube (LH) sampling is applied to reduce the variance of the recourse function point estimates that are used to construct the response surface. Empirical results show the value of the LH method by comparing it with strategies based on independent random numbers, common random numbers, and the Schruben‐Margolin assignment rule. In addition, variance reduction with LH sampling can be guaranteed for an important class of two‐stage problems which includes the classical capacity expansion model. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 753–776, 1999     

基于振动信号提取柴油机低频排气噪声特征研究

针对柴油机低频排气噪声的频率与强度很难准确地用理论计算等困难 ,试验研究了柴油机排气管内低频排气噪声信号与排气管壁上振动信号的相互关系 .结果表明 ,低频范围内 ,振动信号与噪声信号几乎呈现周期性的完全相干 ,在相干频率处振动信号能反映排气噪声的类周期性 .     

军用车辆行动部分疲劳寿命随机有限元分析

阐述了基于随机有限元的车辆行动部分可靠性原理及基本过程,将结构件的弹性模量、泊松比和几何尺寸等因素定义为随机场,并对其进行离散,同时分析了车辆行驶的典型路面的路面谱,利用随机有限元求解在不同的路面状况下车辆行动零部件的受力情况,得到了零部件危险点应力的随机分布和不同路面状况下疲劳可靠性,并对相关的实例进行分析。     

基于随机Petri网的装甲车辆综合电子系统可靠性研究

由于装甲车辆综合电子系统具有耦合性强、动态离散和复杂度高的特点,其难以采用静态故障树方法进行系统可靠性分析,针对这一难题,运用动态故障树方法对系统可靠性进行了分析判别,并运用随机Petri网建立了故障树的仿真模型。以某型车辆为例,通过仿真实验得出了综合电子系统的故障率和可用度指标的动态变化曲线,其分析结果为系统可靠性与测试性设计提供了理论参考。     

管道主动消声的次级声源设计

针对柴油机排气的特点，结合有源噪声控制工程应用，提出了两种次级声源的设计方案，经过分析计算，给出了实验用次级声源．     

Information security: Designing a stochastic‐network for throughput and reliability

Todas information and communication network requires a design that is secure to tampering. Traditional performance measures of reliability and throughput must be supplemented with measures of security. Recognition of an adversary who can inflict damage leads toward a game‐theoretic model. Through such a formulation, guidelines for network designs and improvements are derived. We opt for a design that is most robust to withstand both natural degradation and adversarial attacks. Extensive computational experience with such a model suggests that a Nash‐equilibrium design exists that can withstand the worst possible damage. Most important, the equilibrium is value‐free in that it is stable irrespective of the unit costs associated with reliability vs. capacity improvement and how one wishes to trade between throughput and reliability. This finding helps to pinpoint the most critical components in network design. From a policy standpoint, the model also allows the monetary value of information‐security to be imputed. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009     

基于Prony算法的大型结构振动信号降噪方法

以去除力锤激励下大型结构振动信号的背景噪声为研究目的，分析了背景噪声产生的原因及结构振动信号的特点，提出了将Prony算法应用于降噪的方法。该方法首先用一组衰减余弦信号分量之和来拟合原始信号，得出各衰减余弦信号的参数，然后根据振动信号的特点从中识别出背景噪声并构造其数学表达式，最后进行降噪处理。运用传统Prony算法和改进Prony算法分别对仿真信号和实测信号进行降噪处理，其结果证明了Prony算法的有效性，且改进的Prony算法具有更高的识别精度和更好的降噪效果。     

基于贝叶斯方法的舰船辐射噪声估计

对于潜艇战和反潜战来说,目标的噪声特点和噪声等级是进行声纳作用距离估计的一个重要参数。为了对不确定水声战场环境中的舰船辐射噪声进行有效估计,运用贝叶斯方法分别对正态分布和均匀分布的辐射噪声作了最小均方误差估计和最大后验概率估计,对不同情况下的舰船辐射噪声的估计提供了一种可靠的方法。通过这种方法得出舰船辐射噪声一定的统计规律,为指挥员的精确决策提供信息基础。     

Optimal allocation of minimal repairs in parallel and series systems

In reliability engineering, the concept of minimal repair describes that the repair brings the failed unit (eg, system or component) to the situation which is same as it was just before the failure. With the help of the well‐known Gamma‐Poisson relationship, this paper investigates optimal allocation strategies of minimal repairs for parallel and series systems through implementing stochastic comparisons of various allocation policies in terms of the hazard rate, the reversed hazard rate, and the likelihood ratio orderings. Numerical examples are presented to illustrate these findings as well. These results not only strengthen and generalize some known ones in the seminal work of Shaked and Shanthikumar, but also solve the open problems proposed by Chahkandi et al.'s study and Arriaza et al.'s study.