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911.
介绍了数据仓库和数据挖掘的概念、数据挖掘的过程和方法,简单分析了现代战争中信息处理的特点和需求,阐述了数据挖掘在军事指挥控制系统中的应用必要性,提出了军事应用中数据挖掘系统的层次体系结构,并针对该层次体系结构进一步提出了指挥控制系统中数据挖掘技术的应用模型.  相似文献   
912.
针对协同性联合作战向一体化联合作战转变对作战指挥产生的影响,在正确定位指挥信息流通体系的基础上,从一体化联合作战的本质特征及对指挥信息流通体系的影响出发,设计了基本作战单元指挥信息输入、输出模型,并通过将作战体系区分为四类模块,得出了指挥信息流通体系的逻辑结构.  相似文献   
913.
Burn-in is the preconditioning of assemblies and the accelerated power-on tests performed on equipment subject to temperature, vibration, voltage, radiation, load, corrosion, and humidity. Burn-in techniques are widely applied to integrated circuits (IC) to enhance the component and system reliability. However, reliability prediction by burn-in at the component level, such as the one using the military (e.g., MIL-STD-280A, 756B, 217E [23–25]) and the industrial standards (e.g., the JEDEC standards), is usually not consistent with the field observations. Here, we propose system burn-in, which can remove many of the residual defects left from component and subsystem burn-in (Chien and Kuo [6]). A nonparametric model is considered because 1) the system configuration is usually very complicated, 2) the components in the system have different failure mechanisms, and 3) there is no good model for modeling incompatibility among components and subsystems (Chien and Kuo [5]; Kuo [16]). Since the cost of testing a system is high and, thus, only small samples are available, a Bayesian nonparametric approach is proposed to determine the system burn-in time. A case study using the proposed approach on MCM ASIC's shows that our model can be applied in the cases where 1) the tests and the samples are expensive, and 2) the records of previous generation of the products can provide information on the failure rate of the system under investigation. © 1997 John Wiley & Sons, Inc. Naval Research Logistics 44: 655–671, 1997  相似文献   
914.
The maximum likelihood estimator (MLE) for a distribution function with increasing failure rate is derived, based on a collection of series system data. Applications can arise in industries where operating environments make available only such system-level data, due to system configuration or type-II censoring. The estimator can be solved using isotonic regression. For the special case in which systems contain one component, the estimator is equivalent to the restricted maximum likelihood estimator of Marshall and Proschan [9]. The MLE is illustrated using emergency diesel generator failure data from the nuclear industry. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 115–123, 1998  相似文献   
915.
针对近地卫星数传时的信道时变性和严重的Ka频段雨衰现象,采用自适应编码调制(Adaptive Coding and Modulation, ACM)技术能够充分利用链路资源,相对于传统的固定编码调制方式,进一步提高链路的数据吞吐量。提出近地卫星Ka频段数传链路ACM模式设计方法,在降雨环境下建立Ka频段数传链路模型,根据链路预算的信道状况确定ACM选用模式;采用基于导频符号的最大似然信噪比估计算法结合移动平均的平滑方法实现信道估计,有效地减小了估计值的波动。仿真结果表明,无论晴天还是雨天,采用提出的卫星数传链路ACM模式设计方法,能够在保证系统可靠性的同时获取较高的数据吞吐量。  相似文献   
916.
In progressive censoring, items are removed at certain times during the life test. Commonly, it is assumed that the removed items are used for further testing. In order to take into account information about these additional testing in inferential procedures, we propose a two‐step model of stage life testing with one fixed stage‐change time which incorporates information about both the removed items (further tested under different conditions) and those remaining in the current life test. We show that some marginal distributions in our model correspond either to progressive censoring with a fixed censoring time or to a simple‐step stress model. Furthermore, assuming a cumulative exposure model, we establish exact inferential results for the distribution parameters when the lifetimes are exponentially distributed. An extension to Weibull distributed lifetimes is also discussed.  相似文献   
917.
We consider the classical problem of whether certain classes of lifetime distributions are preserved under the formation of coherent systems. Under the assumption of independent and identically distributed (i.i.d.) component lifetimes, we consider the NBUE (new better than used in expectation) and NWUE (new worse than used in expectation) classes. First, a necessary condition for a coherent system to preserve the NBUE class is given. Sufficient conditions are then obtained for systems satisfying this necessary condition. The sufficient conditions are satisfied for a collection of systems which includes all parallel systems, but the collection is shown to be strictly larger. We also prove that no coherent system preserves the NWUE class. As byproducts of our study, we obtain the following results for the case of i.i.d. component lifetimes: (a) the DFR (decreasing failure rate) class is preserved by no coherent systems other than series systems, and (b) the IMRL (increasing mean residual life) class is not preserved by any coherent systems. Generalizations to the case of dependent component lifetimes are briefly discussed.  相似文献   
918.
This article focuses on the systemic failures of the Nigerian police force to unravel the mysteries surrounding homicides in the country, along with the security, social and political implications of the ongoing trend. The article draws on documented pieces of evidence of high-profile murders, along with the causes of the upsurge in murder incidences and the inhibitive factors relating to the investigative procedures of the police. The suitability of the theory of subaltern realism and the concept of third-world security predicaments in explaining the peculiarities of Nigeria’s internal security challenges is examined, along with the problems of the legitimacy of political regimes and weak borders. There is a need for the National Assembly of Nigeria to exercise its constituted powers in reawakening and supervising investigations into dormant cases of murder through its committees on police affairs, public safety and national security. The police should check its organisational failures, which may be related to using the wrong investigative approaches, low levels of information, limited resources, corrupt practices, and pressure to obtain quick results.  相似文献   
919.
武器装备维修是武器装备维修保障的重要内容,加强装备维修绩效评价,建立科学规范的绩效评价指标体系,对深入推进装备维修工作健康发展将发挥积极作用。以平衡计分卡为研究手段,运用"5M1E"分析法,从一个内核和四个维度出发,分析武器装备维修绩效评价的影响因素,据此建立评价指标体系,并应用于装备维修管理实践,为有效提高装备维修保障效益提供有益借鉴。  相似文献   
920.
ZHANG Xiao 《国防科技》2018,39(1):005-008
党的十九大报告把军民融合发展战略作为七大国家战略之一,明确提出要"更加注重军民融合"。必须将交通领域军民融合视作整个军民融合深度发展的重要突破口,建设军民融合大交通体系。提出以新形势下军事战略方针为统揽,以军民深度融合为途径,聚焦保障军队打赢,大力推进民用交通设施工具贯彻要求;依托国家路网基础,大力推进军地交通运输网络统筹纳入;强化应战应急一体,大力推进各种交通力量建设互补衔接;着眼战略投送能力,大力推进军民交通物流体系有机结合。  相似文献   
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