基于灰色时序的完整性规范技术

计算机系统的完整性安全策略模型与规范问题，是计算机安全研究中最重要的课题之一。已有的研究结果离实际应用还相差太远，例如Ｃｌａｒｋ－Ｗｉｌｓｏｎ完整性模型只是提出了一个框架。本文呈现了我们构造的形式化灰色时序安全策略规范语言（ＧＴＳＬ）。ＧＴＳＬ的理论基础是灰色系统理论和时序规范语言ＬＯ－ＴＯＳ理论。由于它在完整性规范能力、完整性验证过程的构造与表示、责任分离合理性测试等一系列技术方面的完善与创新，使得ＧＴＳＬ成为真正能够实际使用的完整性安全策略规范语言。     

确定性理论在雷达型号识别中的应用

雷达型号识别是雷达对抗情报侦察的首要工作,是近一步分析雷达用途及相关武器系统的基础,也是高层次上的态势评估和威胁估计的主要依据.针对现代战争中电磁信号环境的复杂性,利用单一传感器很难对雷达型号进行准确识别,而基于确定性理论的不确定推理技术能将多个传感器在多个周期的侦察信息进行融合,所以采用确定性理论的数据融合技术,基于确定性理论的组合规则,采用分层式融合算法对雷达型号进行识别.仿真结果表明,该方法的识别结果令人满意,使采用单一传感器可能存在的无法识别或误识别等现象得到了明显的改善.     

Integrating decisions with advance supply information in an assemble-to-order system

We study a periodic-review assemble-to-order (ATO) system with multiple components and multiple products, in which the inventory replenishment for each component follows an independent base-stock policy and stochastic product demands are satisfied according to a First-Come-First-Served rule. We assume that the replenishment for various component suffers from lead time uncertainty. However, the decision maker has the so-called advance supply information (ASI) associated with the lead times and thus can take advantage of the information for system optimization. We propose a multistage stochastic integer program that incorporates ASI to address the joint optimization of inventory replenishment and component allocation. The optimal base-stock policy for the inventory replenishment is determined using the sample average approximation algorithm. Also, we provide a modified order-based component allocation (MOBCA) heuristic for the component allocation. We additionally consider a special case of the variable lead times where the resulting two-stage stochastic programming model can be characterized as a single-scenario case of the proposed multistage model. We carry out extensive computational studies to quantify the benefits of integrating ASI into joint optimization and to explore the possibility of employing the two-stage model as a relatively efficient approximation scheme for the multistage model.     

基于SWOT分析的我国海上方向空中安全形势及对策措施

海上方向是强敌对我实施战略围堵和遏制的主要方向。随着美国国防战略重回大国竞争,其遏制中国的手段推陈出新,尤其是在海空方向对我施压强度频度与日俱增。文章运用SWOT方法对我国海上方向空中安全形势进行了全面分析,认为优势体现在联合作战指挥体制、国防动员能力、列装新型防空武器等方面,劣势体现在战场建设滞后、预警探测拦截打击能力不足等方面,机遇体现在中美共识与相对稳定的周边环境,威胁体现在强敌对我的侦察威慑、空天打击、海空封锁。通过构建我国海上方向空中安全的SWOT分析矩阵,提出要进一步深化改革,加强军队与地方、平时与战时、作战力量和作战环节的“三个统筹”,发展新型防空、预警装备,以及加强沿海防空战场建设等。     

Optimal control policies for an inventory system with commitment lead time

We consider a firm which faces a Poisson customer demand and uses a base‐stock policy to replenish its inventories from an outside supplier with a fixed lead time. The firm can use a preorder strategy which allows the customers to place their orders before their actual need. The time from a customer's order until the date a product is actually needed is called commitment lead time. The firm pays a commitment cost which is strictly increasing and convex in the length of the commitment lead time. For such a system, we prove the optimality of bang‐bang and all‐or‐nothing policies for the commitment lead time and the base‐stock policy, respectively. We study the case where the commitment cost is linear in the length of the commitment lead time in detail. We show that there exists a unit commitment cost threshold which dictates the optimality of either a buy‐to‐order (BTO) or a buy‐to‐stock strategy. The unit commitment cost threshold is increasing in the unit holding and backordering costs and decreasing in the mean lead time demand. We determine the conditions on the unit commitment cost for profitability of the BTO strategy and study the case with a compound Poisson customer demand.     

Collective security and strategic instability in the digital domain

Cyberspace experiences worrying trends that could have a negative impact on the international strategic landscape. The lack or erosion of norms and risky practices and behaviors could lead to greater uncertainty and thus greater instability. Set against a context of renewed competition between great powers, these developments are also tied to the strategic structure of cyberspace. This forum is devoted to discussing factors leading to stability or and instability.     

The Somali National Army: an assessment

To engage properly with the Somali National Army, to understand it in the hope of improving stability and the lives of over 12 million Somalis, good basic information on its composition and characteristics is necessary. Authoritative accounts on the subject have been scarce for over 25 years. This account seeks to detail the army’s dispositions across southern Somalia, and, more importantly, the brigades’ clan compositions and linkages. Clan ties supersede loyalties to the central government. The army as it stands is a collection of former militias which suffer from ill-discipline and commit crime along with greater atrocities. Estimates of numbers are unreliable, but there might be 13,000 or more fighters in six brigades in the Mogadishu area and five beyond.     

区块链在分队战术协同中的应用构想

从战术分队角度出发,探讨了区块链技术在作战实体之间的信息交互及智能协同方面的应用设想,分析了战术分队信息交互的相关技术及面临的挑战,阐述了区块链在未来战术分队指挥体系构建中的发展构想。     

基于位置信息的无线传感网络路由改进

基于位置信息的无线传感器网络如果完全采用无状态的方式路由,在某些拓扑结构中存在数据不可到达的缺陷,即死亡点的问题.针对这一问题,将无线传感器网络抽象为一数学模型,在此模型的基础上,给出了问题的数学描述.经分析,提出了一种基于逃离算法的详细解决方案.对算法的性能从理论上分析得出算法没有环路,是正确可行的,而仿真结果也验证了这一点,算法的时间复杂度为O(n).     

Agent的多传感器管理方案

多Agent系统(Multi-Agent System,MAS)以其智能性和交互协作等优点在分布式系统中得到了广泛的应用.火控系统组网就是通过把分立的火控系统通过某种网络结构连接起来,以提高火控系统的整体性能,是一个典型的分布式系统.以火控系统组网为背景,将Agent技术应用于组网系统中的多传感器管理,并采用了基于角色的任务分解思想.提出了基于多Agent的传感器管理结构模型,分析了各个组件Agent的功能.