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151.
152.
Statistical analysis for masked system life data from Marshall‐Olkin Weibull distribution under progressive hybrid censoring
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This paper considers the statistical analysis of masked data in a series system, where the components are assumed to have Marshall‐Olkin Weibull distribution. Based on type‐I progressive hybrid censored and masked data, we derive the maximum likelihood estimates, approximate confidence intervals, and bootstrap confidence intervals of unknown parameters. As the maximum likelihood estimate does not exist for small sample size, Gibbs sampling is used to obtain the Bayesian estimates and Monte Carlo method is employed to construct the credible intervals based on Jefferys prior with partial information. Numerical simulations are performed to compare the performances of the proposed methods and one data set is analyzed. 相似文献
153.
针对装备保障中维修调度对装备训练及可靠性的影响,将支队级修理所保障多艘舰船维修工作的情况抽象为单一维修台保障多个系统的维修力量调度分配,引入修理工可变休假策略对其进行描述,以装备结构中常见的n中取k系统为研究对象,针对以往研究利用指数分布等典型分布导致模型约束条件过于严格的问题,利用连续Phase-type分布描述了系统相关随机变量,构建系统可靠性解析模型,通过算例验证了模型适用性,模拟分析了修理工有无休假、修理工休假速率等相关因子对系统运行指标产生的各种影响。算例结果表明,该可靠性模型可以有效复现维修力量调度对n中取k系统可靠性的影响,可为修理工休假次数的合理安排、系统部件数量的优化配置提供理论基础和实践参考。 相似文献
154.
主成分分析网络(principal component analysis network, PCANet)是一种简单的深度学习算法,在图像识别领域具有优秀的性能。将图嵌入思想融入PCANet,提出一种新的图像识别算法光滑主成分分析网络(Smooth-PCANet)。为了验证Smooth-PCANet算法的有效性,在人脸、手写体字符以及图片等不同数据集上构建实验,并将Smooth-PCANet与多种基于深度学习的图像识别算法作了对比。实验结果证明,Smooth-PCANet算法比PCANet获得了更高的识别性能,并且更有效地避免了过拟合,在小样本训练时具有显著优势。 相似文献
155.
量子保密通信是利用量子力学的基本原理来实现信息无条件安全传递的一种全新密码方法,其核心是量子密钥分发。2014年正好是量子保密通信的第一个协议—BB84协议提出30周年。经过30年的发展,量子保密通信在理论和实验上都得到了快速发展,实际工程应用也初具规模。文章对量子保密通信的历史发展及研究现状进行了简要回顾,特别介绍了基于实际量子保密通信系统的量子黑客和防御。最后,对未来的几个研究方向进行了简要讨论。 相似文献
156.
通过分析悬浮式深弹发射后在空中的弹道特性,建立了深弹弹着点坐标的计算模型。采取蒙特卡洛方法,分别对舰艇六自由度状态下,单管和六联装火箭深弹的弹着点坐标进行了仿真计算,对弹着点的分布规律进行了研究,并得出弹着点的联合密度函数。结果表明,在发射参数存在正态扰动下,弹着点散布区域均呈椭圆形分布,弹着点坐标均仍服从正态分布。 相似文献
157.
魏来 《中国人民武装警察部队学院学报》2014,(6):72-74
近年来,各地小型旅馆发展迅速,但由于其小而散使消防安全监管难度增大,从业人员消防安全意识淡薄,自身消防安全隐患较多,极易发生群死群伤火灾事故.介绍了小型旅馆的特点,分析了小型旅馆存在的消防安全隐患及消防监督管理工作存在的问题,探讨了加强小型旅馆消防安全管理的措施. 相似文献
158.
首先,在研究飞行器背景磁干扰模型与小信号模型的基础上,分析了地磁梯度沿纬度与高度的变化规律,分析可知由于飞行器的机动,地磁梯度会对测量结果造成影响;然后,考虑地磁梯度因素,对原有小信号模型求解方法进行了改进:飞行器在四个航向上做小角度的机动飞行,将地磁场沿纬度与高度的梯度作为未知量,与飞行器磁干扰模型中的剩磁参数、感磁参数和涡磁参数一起求解;最后,利用实测试验数据进行了验证,结果表明:考虑地磁梯度的影响与不考虑地磁梯度的影响相比,求解的模型参数可以在细节上进一步提高飞行器背景磁干扰的补偿效果。 相似文献
159.
Bertrand Fonck 《Small Wars & Insurgencies》2014,25(4):767-783
In the late seventeenth century during the Dutch War (1672–1678) and the Nine Years War (1688–1697), French armies relied on small war for the accomplishment of essential tasks and as part of an overall strategy of exhausting their opponents in the Low Countries. The purposes of small war included the imposition of contributions on enemy populations, the destruction of the enemy base of operations, blockades of fortresses, and the general support of campaign armies. The expression ‘small war’ in the French language appeared with growing frequency in the 1690s. Small war can be viewed as both a cause and consequence of the characteristics of these wars. The limited policy goals of Louis XIV the king of France required a strategy that minimised risk and accomplished the goal of reducing if not eliminating the Spanish presence in the Low Countries that bordered the north of France. As French armies increased in size during this period, the demand for specialists at small increased in order to provide security and ensure supply. Small war in the late seventeenth century was thus not ideologically motivated insurgency, but in the minds of French commanders an essential component of strategy and the nature of war. 相似文献
160.
Stochastic framework for partially degradation systems with continuous component degradation‐rate‐interactions
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Many conventional models that characterize the reliability of multicomponent systems are developed on the premise that for a given system, the failures of its components are independent. Although this facilitates mathematical tractability, it may constitute a significant departure from what really takes place. In many real‐world applications, system components exhibit various degrees of interdependencies, which present significant challenges in predicting degradation performance and the remaining lifetimes of the individual components as well as the system at large. We focus on modeling the performance of interdependent components of networked systems that exhibit interactive degradation processes. Specifically, we focus on how the performance level of one component affects the degradation rates of other dependent components. This is achieved by using stochastic models to characterize how degradation‐based sensor signals associated with the components evolve over time. We consider “Continuous‐Type” component interactions that occur continuously over time. This type of degradation interaction exists in many applications, in which interdependencies occur on a continuum. We use a system of stochastic differential equations to capture such “Continuous‐Type” interaction. In addition, we utilize a Bayesian approach to update the proposed model using real‐time sensor signals observed in the field and provide more accurate estimation of component residual lifetimes. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 286–303, 2014 相似文献