Simulation of the plasticizing behavior of composite modified double-base (CMDB) propellant in grooved calendar based on adaptive grid technology

The frequent occurrence of safety accidents during the calendering process is caused by the flammable and explosive properties of composite modified double-base (CMDB) propellant. Optimization of process parameters with the aid of fluid simulation technology could effectively ensure the safety of the calendering process. To improve the accuracy of the simulation results, material parameters and model structure were corrected based on actual conditions, and adaptive grid technology was applied in the local mesh refinement. In addition, the rheological behavior, motion trajectories and heat transfer mechanisms of CMDB propellant slurry were studied with different gaps, rotational rates and temperatures of two rollers. The results indicated that the refined mesh could significantly improve the contour clarity of boundaries and simulate the characteristics of CMDB propellant slurry reflux movement caused by the convergent flow near the outlet. Compared with the gap, the increased rotational rate of roller could promote the reflux movement and intensify the shear flow of slurry inside the flow region by viscous shear dragging. Meanwhile, under the synergistic effect of contact heat transfer as well as convective heat exchange, heat accumulated near the outlet and diffused along the reflux movement, which led to the countercurrent heat dissipation behavior of CMDB propellant slurry. The plasticizing mechanism of slurry and the safety of calendering under different conditions were explored, which provided theoretical guidance and reference data for the optimization of calendering process conditions. Based on the simulation results, the safety of the CMDB propellant calendering process could be significantly improved with a few tests conducted during a short research and development cycle.     

讯问过程中火灾事故责任者心理分析及对策研究

火灾事故责任者往往为了逃避法律制裁,施用各种手法抗拒交代案件的真相。正确研究分析火灾责任者在讯问过程中的心理特点、表现及成因,并科学运用讯问方法、策略,可以为公安消防机构迅速准确认定火灾事故原因和火灾事故责任,提供重要的证据,从而实现火灾事故调查工作的突破。     

一种导引头信号处理器通用硬件平台方案

导引头信号处理器是导引头的核心装置,随着技术的迅速进步,信号处理器的功能也越来越复杂。如何缩短信号处理器的开发周期、降低开发成本,对于信号处理器的设计师来说是非常重要的。提取了不同型号、不同体制导引头对信号处理要求的共同特征,提出了一种导引头信号处理器通用硬件平台方案。在新产品模样开发阶段,可以在这种硬件平台上进行系统验证和软件开发;基于面向对象的概念,在试样设计阶段可以继承通用平台中的部分或全部属性,快速构建适合于新产品电气性能和结构要求的硬件平台。     

基于ExSpect的维修过程建模与仿真研究

应用ExSpect语言,采用自上而下的系统分析方法,建立了反映产品维修过程中的资源竞争、并发和同步关系的Petri网模型。最后进行了仿真实例研究和分析。     

基于IDEF3的部队装备中修业务流程优化重组

以IDEF3为工具描述了部队装备中修业务流程,分析了流程中存在的问题,通过采用基于状态的维修方式、无损检测先进技术手段、共享维修保障信息和调整器材发放审批权限等方法,对部队现行装备中修业务流程进行了优化,可有效解决装备维修过剩、维修不足、维修资源浪费和维修周期过长等问题．     

基于可执行模型架构的成像侦察卫星系统建模与仿真

成像侦察卫星系统内部关系复杂、任务需求种类较多,利用基于町执行模型架构的系统工程对其进行建模研究,可以有效地实现从模型到仿真的综合集成．通过研究可执行模型架构理论,集成UPDM与成像侦察卫星系统功能模型,对成像侦察卫星系统进行了建模与仿真,验证了可执行模型架构的有效性与实用性．     

Service design at diagnostic service centers

We study a service design problem in diagnostic service centers, call centers that provide medical advice to patients over the phone about what the appropriate course of action is, based on the caller's symptoms. Due to the tension between increased diagnostic accuracy and the increase in waiting times more in‐depth service requires, managers face a difficult decision in determining the optimal service depth to guide the diagnostic process. The specific problem we consider models the situation when the capacity (staffing level) at the center is fixed, and when the callers have both congestion‐ and noncongestion‐related costs relating to their call. We develop a queueing model incorporating these features and find that the optimal service depth can take one of two different structures, depending on factors such as the nurses' skill level and the maximum potential demand. Sensitivity analyses of the two optimal structures show that they are quite different. In some situations, it may (or may not) be optimal for the manager to try to expand the demand at the center, and increasing skill level may (or may not) increase congestion. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012     

Double Mover–Stayer model on customer switching in telecommunications industry

Customer acquisition and customer retention are the most important challenges in the increasingly competitive telecommunications industry. Traditional studies of customer switching always assume that customers are homogeneous, and thus that model customer switching behavior follows a Markov formulation. However, this postulation is obviously inappropriate in most instances. Blumen et al. (Cornell Studies of Industrial and Labor Relations, Cornell University Press, Ithaca, NY, 1955) developed the Mover–Stayer (MS) model, a generalization of the Markov chain model, to relax the requirement of homogeneity and allow the presence of heterogeneity with two different types of individuals—“stayers,” who purchase the same kinds of products or services throughout the entire observation period; and “movers,” who look for variety in products or services over time. There are two purpose of this article. First, we extend the MS model to a Double Mover‐Stayer (DMS) model by assuming the existence of three types of individuals in the market: (1) stable and loyal customers, who have stable usage within the same company; (2) instable but loyal customers, whose usage varies within the same company over time; and (3) disloyal customers, who switch from one company to another to seek for new experiences or/and benefits. We also propose an estimation method for the DMS model. Second, we apply the DMS model to telecommunications data and demonstrate how it can be used for pattern identification, hidden knowledge discovery, and decision making. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012     

基于灰色系统理论的军队油料节约人员360度绩效评估

基于360度绩效评估理论,从德、能、勤、绩4个方面构建了包含4个1级指标和16个2级指标的军队油料节约人员360度绩效评估指标体系。利用层次分析法确定了各评估指标的权重,运用灰色系统理论的原理和方法,构建了多层次灰色评估模型,并对某油料节约小组5位油料节约人员进行了360度绩效评估。案例应用表明,此方法具有系统综合各层评估者提供的"贫信息"的优点,不仅能得出被评估者的灰类及优劣顺序,而且得到了各指标所属灰类和具体的灰色评价权值,使360度绩效较好地实现了绩效反馈的目的。该研究为军队油料节约人员绩效管理工作提供了新的思路和方法。     

指标融合和隐马尔可夫模型的舰船装备技术状态评估

科学合理的技术状态评估技术是保障舰船安全性和任务完好性的有效途径之一,针对目前舰船装备技术状态评估缺乏动态性以及评估指标过多的问题,构建舰船装备技术状态多指标融合模型,结合技术状态评估指标融合模型和隐马尔可夫模型所具有双随机性和严谨数学推理能力的特点,建立基于指标融合模型和隐马尔可夫模型的舰船装备技术状态动态评估模型。最后通过案例分析验证了所提出的方法能够有效体现技术状态评估中的动态性,为舰船装备技术状态评估提供新的途径。