Steady‐state diffusion approximations for discrete‐time queue in hospital inpatient flow management

In this article, we analyze a discrete‐time queue that is motivated from studying hospital inpatient flow management, where the customer count process captures the midnight inpatient census. The stationary distribution of the customer count has no explicit form and is difficult to compute in certain parameter regimes. Using the Stein's method framework, we identify a continuous random variable to approximate the steady‐state customer count. The continuous random variable corresponds to the stationary distribution of a diffusion process with state‐dependent diffusion coefficients. We characterize the error bounds of this approximation under a variety of system load conditions—from lightly loaded to heavily loaded. We also identify the critical role that the service rate plays in the convergence rate of the error bounds. We perform extensive numerical experiments to support the theoretical findings and to demonstrate the approximation quality. In particular, we show that our approximation performs better than those based on constant diffusion coefficients when the number of servers is small, which is relevant to decision making in a single hospital ward.     

降维状态观测器的两种设计方法及算例

降维状态观测器是非常重要的一类观测器,它使采用状态反馈构成闭环系统的物理实现成为可能。降维状态观测器的设计方法很多,笔者在一种常用设计方法的基础上,推导出对应的另一种设计方法,这将使降维观测器设计考虑的情况更全面,为使用方便,针对这两种方法给出了算例。     

从治国理政的高度大力推进生态文明建设

建设生态文明是我们党对人类社会发展规律和社会主义现代化建设规律认识的新发展,也体现了我们党执政理念的进一步完善。因此必须从治国理政的战略高度认识并推进生态文明建设。建设生态文明是破解我国发展中种种难题的现实途径、全面建成小康社会的迫切要求、实现中华民族永续发展的客观要求,必须从树立生态文明理念、转变经济发展方式、建立完善生态文明制度机制着手。同时,生态文明建设也是军队建设科学发展的题中应有之义。     

导弹主/被动雷达复合制导中的目标状态估计

针对主 /被动雷达复合制导中的被动雷达只有角度信息而无径向距离信息 ,当被动雷达与目标间的相对加速度为零时 ,目标的距离状态是不可观的特点 ,提出了一种旨在获取被动雷达径向距离信息的方法 ,从而可利用主动雷达和被动雷达的角度和径向距离信息进行数据融合。仿真结果表明 ,利用此方法可得到较好的数据融合效果。     

一阶交流电路暂态分析

以RC串联电路为例,介绍一阶线性电路交流暂态过程的基本分析方法.通过三种不同方法的比较,归纳出对于不同电路应当采取不同处理办法.     

未来能量互联的关键设备——固态变压器

固态变压器作为能源互联网中实现能量转换和控制的关键设备,有很多方面需要进行深入研究,文章结合固态变压器的自身特点,对其主要发展的核心技术,包括基于SiC新型宽禁带材料的研制、基于SiC的固态功率器件和固态变压器设计与实现、固态变压器的先进控制策略研究等进行了详细阐述。     

Is strategic studies narrow? Critical security and the misunderstood scope of strategy

Critical security advocates commonly portray strategic studies as crippled by its narrow focus on Cold War-era military issues, as state-centric and as Western-centric. I argue that this conception of the scope of strategy is flawed and I offer a comprehensive rebuttal by working out the logic of the theories advanced by Carl von Clausewitz and Thomas Schelling. The proponents of critical security overlook the striking expansion of strategy during the Cold War, its longstanding inclusion of competing political actors not just states, as well as its capacity to put Western and non-Western actors in a common analytic frame. By breaking out of the conceptual jails in which strategy has been incarcerated, I seek to reconnect International Relations to strategic thought from which it has become increasingly estranged.     

因素状态值为模糊数的变权综合决策方法

对因素权重为实数、因素状态值为模糊数的多因素不确定性决策问题,由实数型状态变权向量导出模糊数状态变权向量,得出模糊数变权公式,建立模糊数变权综合决策模型,最后给出一个应用模糊数变权综合决策模型的实例.     

The effect of foreign state support to UNITA during the Angolan War (1975–1991)

ABSTRACT

State support for foreign rebel groups has become more salient, yet it remains unclear how this affects armed conflict. This paper therefore analyses the effect of foreign government assistance and does so in the typical case of the Angolan War (1975–1991). It argues that South African and United States support greatly helped the National Union for the Total Independence of Angola (UNITA) wage a large and sustained insurgency campaign but was ultimately insufficient to overthrow the People’s Movement for the Liberation of Angola (MPLA) government because it enabled the incumbent government to obtain similar foreign assistance and because the level of aid awarded to UNITA fluctuated strongly, preventing it from engaging in meaningful long-term planning.     

基于排队论的空降兵部队安全着陆问题研究

针对空降兵部队安全着陆问题,首先建立空降排队模型,明确空降作战受到火力打击时为混合制排队论问题,对具体空降参数进行了分析与计算,得到了比较科学的结果,与实际基本相符,然后根据结果分析了各种参数对空降作战的影响,提出了空降作战提高安全着陆人数的对策,对空降作战人数的安排及火力的支援提供了较强的参考价值,为开展空降作战相关问题研究提供可借鉴的思路方法。