负离子的相对论性Xα法计算

本文用相对论性X_α法计算了N~-、O~-、F~-、S~-、Cl~-等负离子的组态平均能和单电子能量本征值;讨论了相对论性X_α法在计算负离子时的不稳定性问题,并且给出了解决这种不稳定性问题的方法。     

数字横向滤波器实现频率鉴别

本文讨论了数字横向滤波器实现频率鉴别的原理。具体分析了利用自相关及自复卷积方法实现频率鉴别的方法,得出了鉴频特性斜率值及鉴频带宽的关系式,计算并给出了鉴频特性∑I～ω、ΔQ～ω的关系曲线。这种频率鉴别方法可以用在接收相参系统中的自动频率微调。     

基于簇的Ad Hoc网络密钥管理机制研究

Ad Hoc网络可以不依赖于现有网络基础设施,快速搭建起一个移动通信网络,然而其灵活性又使其安全性面临着严峻的挑战.密钥管理是Ad Hoc网络安全的关键技术,在分析现有的Ad Hoc网络分布式信任方案基础上,提出一种有效的基于簇的密钥管理方案.该方案实现了节点之间的双向认证,具有较强的抗假冒攻击能力,密钥分发过程简单,...     

化学毒剂及相关化合物的色谱及质谱分析检测研究进展

介绍了当前对毒剂及相关化合物的色谱及质谱分析检测研究进展和发展趋势。仪器设备方面,气相色谱-质谱联用仪仍是主力仪器：但对热不稳定性及难挥发性化合物来说,用液相色谱-质谱来分析则更为合适;发展现场可用的、便携式鉴别技术和设备也是一个发展趋势。分析化合物方面,不能局限于附表化学品,应该积极开展对毒素及毒物与生物体加合物等复杂化合物的分析研究。样品基质方面,应该展开对新型消毒剂样品及生物样品的研究。     

某型炮兵子母弹子弹引信安全性分析

文章阐述了某型炮兵子母弹子弹引信作用原理及安全性设计准则。进而依据GJB 373A—1997《引信安全性设计准则》对该型炮兵子母弹子弹引信进行安全性分析,认为子弹引信的安全性设计满足《引信安全性设计准则》的相关要求,特别具有延期解除保险、非正常时序故障保险、子弹成串防错装和瞎火状态识别等安全特性。     

华东军政大学加强学校建设的六大举措

华东军政大学在两年多的办学治校历程中,始终注重加强学校建设,采取了一系列行之有效的措施。其中,收效最为显著的有六大举措:一、开展立功创模运动,全面推进学校建设;二、开展诉苦运动,提高阶级觉悟;三、结合土地改革教育,开展新式整军运动;四、弘扬革命传统,整顿作风纪律;五、颁布行政干部职责,明确相关人员责任;六、开展控诉坦白运动,改造起义解放军官,为学校践行"一切为了战争,一切为了前线,一切为了胜利"的办校方针,奠定了坚实的基础。     

Modeling and analysis of a mixed‐model assembly line with stochastic operation times

We consider a mixed‐model assembly line (MMAL) comprised a set of workstations and a conveyor. The workstations are arranged in a serial configuration. The conveyor moves at a constant speed along the workstations. Initial units belonging to different models are successively fed onto the conveyor, and they are moved by the conveyor to pass through the workstations to gradually generate final products. All assembling tasks are manually performed with operation times to be stochastic. An important performance measure of MMALs is overload times that refer to uncompleted operations for operators within their work zones. This paper establishes a method to analyze the expected overload times for MMALs with stochastic operation times. The operation processes of operators form discrete time nonhomogeneous Markov processes with continuous state spaces. For a given daily production schedule, the expected overload times involve in analyzing the Markov processes for finite horizon. Based on some important properties of the performance measure, we propose an efficient approach for calculating the expected overload times. Numerical computations show that the results are very satisfactory. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007     

Technical note: Worst‐case performance of power‐of‐two policies for serial inventory systems with incremental quantity discounts

This study presents power‐of‐two policies for a serial inventory system with constant demand rate and incremental quantity discounts at the most upstream stage. It is shown that an optimal solution is nested and follows a zero‐inventory ordering policy. To prove the effectiveness of power‐of‐two policies, a lower bound on the optimal cost is obtained. A policy that has a cost within 6% of the lower bound is developed for a fixed base planning period. For a variable base planning period, a 98% effective policy is provided. An extension is included for a system with price dependent holding costs. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007     

柴油机热力性能的灰色预测

提出了一种基于柴油机示功图数据分析及灰色预测理论的柴油机热力性能预测方法.该方法从一系列实测示功图压力数据中还原燃烧规律,提取燃烧规律曲线的特征值,并采用灰色预测理论来预测未来的燃烧规律,代入柴油机工作过程计算程序中得到其各热力参数,具有一定的理论及实用价值.     

非单调关联故障树顶事件失效概率的新算法

提出了一种计算非单调关联故障树顶事件失效概率的新方法,其基本思想是利用ＢＤＤ进行故障树中顶事件的不交化工作,可避免求ＰＩＳ和ＰＩＳ的最小覆盖的运算过程,为有效解决其运算的ＮＰ困难问题提供了一条新的途径。