基于双路由单元的SpaceWire总线性能评价方法研究*

本文基于双路由单元研究了SpaceWire总线的性能评价体系。研究中,首先给出了双路由单元的定义,推导了基于双路由单元的路由系统的数据传输时间和资源耗费的计算方法;其次推导了基于双路由单元的多路由拓扑系统的性能评价体系;然后采用蒙特卡洛模拟的方法建立了双路由单元系统的模拟平台,仿真计算了路由单元在不同接口配置情况下的性能。研究结果表明：基于双路由单元的传输时间和资源耗费指标能够评价SpaceWire总线的性能;并且在不同接口配置时,存在一种最佳的配置方式能够使得系统的性能达到最优。     

SpaceWire网络热点通信模式的缓存资源分配算法

基于SpaceWire网络在热点通信模式下的工作特点,研究缓存资源的分配算法。给出均匀通信模式和热点通信模式的释义;推导网络路由节点的满负荷概率和平均延时的解析方法,计算网络中的关键通信节点;再给出SpaceWire网络缓存资源分配算法。利用Opnet网络仿真平台建立SpaceWire通信模型,仿真了不同通信模式中采用缓存优化策略前后的关键性能指标。研究结果表明:在热点通信模式状态下,该缓存资源分配算法在保证总资源一定的前提下,网络系统的平均延时降低,优化了SpaceWire网络性能。     

基于X射线脉冲星的导航半实物仿真系统

为验证X射线脉冲星导航的关键技术,本文描述了基于X射线脉冲星导航的半实物仿真系统组成和工作原理,并搭建了基于X射线脉冲星导航的半实物仿真系统。系统由信号模拟单元、信号接收单元和导航估计单元组成,此系统可有效模拟X射线脉冲星导航的星源强度、周期及脉冲轮廓,记录X射线脉冲星单光子到达时间,恢复X射线脉冲星脉冲轮廓,计算X射线脉冲到达时间及导航估计解算。所设计的半实物仿真系统为X射线脉冲星导航算法测试提供了有效手段,对X射线脉冲星自主导航研究的可行性验证、动态性能测试以及工程应用具有一定的参考价值。     

一种六通道高速数据采集系统的设计

提出并实现了一种基于PCI总线六通道高速采集系统的结构。该系统采用微机作为采集主控单元 ,兼容三种体制雷达的采集要求 ,可以实现六通道同时采集和大容量数据的存储 ;为了实现高速和大容量采集 ,系统采用S5 933作为PCI总线接口 ,利用PCI总线的高速传输能力 ,满足主控单元与采集单元的数据传输要求 ;同时利用双口RAM内部切换保证连续采集和连续传输 ;控制电路采用FPGA实现 ,简化了电路板设计 ,提高了灵活性。软件系统在WindowsNT平台上实现 ,保证了整个系统的安全性与稳定性。     

基于SDN与传统路由相结合的网络架构设计

针对灾区、战场等复杂环境对通信网络性能的高需求,以及传统的冗余繁杂的紧耦合网络架构发展滞后等问题,提出了一种基于SDN架构与传统路由协议相结合的新型网络架构。该架构的设计思想是先由传统路由完成网络初始联通状态的建立,在此基础上再利用SDN架构技术实现对应用业务和通信网络资源的分析感知、计算、评估等。分别对SDN控制器、南北向接口和传统路由协议进行设计。试验结果表明了该方案的优越性,具有重要的应用和参考价值。     

(2015GIS)北斗静止轨道卫星信号盲区快速并行解算方法

北斗系统静止轨道卫星信号盲区解算方法复杂、串行计算耗费时间长,需在并行环境下利用更多的计算资源进行北斗盲区的快速解算。本文在分析北斗盲区解算原理与算法并行特征基础上,提出了基于动态盲区影响域的并行解算方法,并以栅格单元为并行粒度进行任务划分,实现了北斗盲区的高效并行解算。基于全国范围59景数字高程模型数据,利用8进程进行盲区并行解算,耗费时间约为5小时。实验测试结果表明：算法的并行效率随着进程数的增加有所衰减,但稳定在96%以上。基于本文方法实现的程序中间件已集成应用于高性能地理信息平台中,应用效果良好。     

基于PXI总线的通装机液平台综合测控系统标准化设计

自动测试系统的发展趋势是标准化设计和采用开放式系统框架。基于PXI总线的平台综合测控系统采用了统一硬件系统、统一软件开发平台、统一标准接口的开放式体系结构和标准化设计。通过对用户开放测控资源定义和标准化设计软硬件接口,使平台综合测控系统软、硬件具有开放性和互换性,满足了不同保障对象的测试需求,对通用装备检测试验设备的通用化、标准化、集成化发展起到了积极的推动作用。     

大型k/N系统维修资源优化配置模型

为解决大型k/N系统维修资源的配置问题,建立了一种维修资源优化配置模型。首先,根据大型k/N系统故障单元的维修特点提出了批量m维修策略,并基于此策略建立了k/N系统使用可用度模型,利用M~Q/M/c排队理论对影响系统使用可用度的关键指标进行了计算和修正;然后,建立了由多个k/N系统组成的复杂装备的多种维修资源的优化配置模型,采用边际效应分析法对多种维修资源进行综合优化;最后,通过算例仿真与分析对所提出的模型进行了验证。结果表明,所建立的模型具有一定的可行性与有效性,能为装备维修保障人员提供决策支持。     

一种面向宽带复杂信号侦察的可配置计算应用框架

可配置计算系统的优势与系统设计过程的复杂性是一对矛盾,可配置计算框架为此提供了有益的思路。但受限于适用范围与通用性考虑,已有的特别是商业框架仅支持系统的静态重构。本文针对宽带信号侦察这一特定应用领域,提出了一种功能级可配置计算应用框架BSRRCS-RCAF,该框架将领域应用中具有共性的计算与功能模块抽取和集中起来,形成二进制比特流配置文件库,并提供构建此类系统的公共服务体系。基于公共服务体系以及配置文件库,当需要修改或者重新构建宽带信号侦察系统时,只需在现有框架下动态调用配置组件库,或者遵循框架的统一设计接口完善补充组件库中的特定功能部分,整个系统设计框架将得到方便复用,便于实现基于快速重构的多种系统功能。     

基于SDN的分布式无线网络架构及控制器配置策略

基于单一控制器的SDN架构容易导致无线网络性能受到影响,尤其针对高动态无线网络,将大幅降低其健壮性和鲁棒性。鉴于此,提出了一种分布式软件定义网络架构(Distributed Software Defined Wireless Network,DSDWN),该架构是基于完全分布式和分层式SDN思想提出的,包括主从控制器和事件传播系统,在该架构下提出了控制器系统的配置策略和主控制器的选择策略。仿真验证表明,提出的控制器配置策略在时延方面优于贪婪算法和聚类算法,更适合高动态无线网络环境;基于多目标优化的主控制器选择策略,优化了网络链路连接时长、总时延及节点资源,降低了路由开销。     

Helping hands: civil–military cooperation and Italy's military operation abroad

In the Post-Bipolar Era the growing complexity of the military operations requires a new approach for the resolution of international crises. Since the end of the Cold War, peace support operations (PSO) have become the mainstay and principal occupation of most Western armies. At the same time, Italy has been one of the most important actors in such an area. The article focuses on the cooperation between military and civil components (a process called CIMIC) as a key variable in the Italian PSOs. We will analyse in detail the main lessons learned from past military interventions as well as the general context in which new tendencies are taking place. The maintaining of a minimum security frame becomes essential to fulfil activities ‘collateral’ to the mission: reconstructing services and infrastructure, food distribution, water and medication, law and order, de-mining, training of local forces, and supporting local institutions. These are the main tasks to obtain thrust and support from the population.     

Terrorism,insurgency, kidnapping,and security in Africa's energy sector

Energy continues to serve as the bedrock of modern economies and the main driver of modern society. For Africa, the production and supply of energy resources such as crude oil, natural gas, uranium, coal, biomass, biofuels and other renewables are an important source of employment, rents, taxes, royalties and profits. This sector brings in several tens of billions of dollars of revenue annually. The production and delivery of such resources, however, depend on critical infrastructures such as pipelines, refineries, processing plants, terminals, rigs, electrical energy pylons, substations, pump stations, vessels, and tankers. These infrastructures have been attacked by terrorists, insurgents, vandals and saboteurs, all of whom see them as targets against which to register their grievances and extract concessions from the state. This paper is a chronological account of some of the documented incidents of terrorism, insurgency, kidnapping, destruction, sabotage, and human casualties suffered in the oil and gas sectors in Africa between 1999 and 2012. It is based on data extracted from the databases of the RAND Database of World Terrorism Incidents and the University of Maryland's Global Terrorism Database (GTD).     

A1 Qaeda and the radical Islamic challenge to western strategy

The September 11 global crisis prompted by the attacks on the World Trade Center and the Pentagon raises major questions concerning the nature and trajectory of terrorism in the post-Cold War global order. Hitherto, terrorism has been largely debated by analysts at the level of nation states. Terrorist and insurgent movements have also been largely anchored in nationalist and ethnic power bases even when they have sought to mobilise a transnational ideological appeal on religious or class grounds. There have been a few exceptions to this pattern such as the alliance between the German Baader-Meinhof group and the Japanese Red Army Faction, but even such international alliances as this did not, until at least the 1980s, presage anything like a global terrorist network necessitating a global strategic response. This study examines terrorism and global strategic responses.     

Tacit support for terrorism: The rapprochement between the USSR and Palestinian guerrilla organizations following the 1967 war

This article demonstrates the inconsistent and wavering Soviet attitude towards national liberation movements in general and the Palestinian organizations in particular. Until the late 1960s, the Soviets viewed these organizations with suspicion, hesitating to engage in political dialogue with them. However, in the 1970s, political and military events in the region, as well as modifications in the Kremlin's Cold War strategies, led to a general shift towards the Middle East in Soviet foreign policy. Soviet leaders showed increased willingness to provide certain Palestinian organizations with arms with which to conduct terrorist activities against Israeli, pro-Israeli, Jewish and Western targets. The article explores the complex relations between Palestinian organizations and the USSR in the field of international terror. The study also exposes and analyzes the nature and content of Soviet–Palestinian arms dialogues and transactions. It provides clear evidence that Soviet policymakers and other luminaries were fully informed of, and sometimes directly involved in, these transactions and dialogues at the highest levels.     

The UK,interrogation and Iraq, 2003–2008

The UK’s interrogation operations during the conflict in Iraq (2003–2008) are often portrayed by the media as involving significant amounts of mistreatment. This article demonstrates that these practices are not necessarily representative of the UK’s interrogation operations across this conflict. In doing so it contributes to the limited literature on the practice of interrogation and on the UK’s combat operations in Iraq. The UK’s interrogation capability, and therefore its intelligence-gathering capability, is shown to have rested primarily with the military’s Joint Forward Interrogation Team (JFIT). The JFIT suffered from limitations to the number, training and experience of its interrogators and interpreters. It is argued that maintaining a permanent, higher level of preparedness for interrogation by the British armed forces is desirable.     

Remembering and forgetting Mirambo: Histories of war in modern Africa

ABSTRACT

While the study of organised violence is considered essential to understanding the history of the West, and accordingly imbued with various layers of meaning and remembrance, war is widely regarded as inimical to the modern nation in Africa and stable development more broadly. Using examples drawn from primarily from East Africa, this paper considers the ways in which warfare in the deeper (‘precolonial’) past has been framed and envisioned in recent decades, in particular by governments whose own roots lie in revolutionary armed struggle and who began life as guerrilla movements. While in some cases particular elements of the deeper past were indeed mobilised in pursuit of contemporary political goals, in many other scenarios histories of precolonial violence were beheld as problematic and unworthy of remembrance. This paper highlights the paradox and ambiguity which has attended the memory of key aspects of Africa’s deeper past.     

SIM—LISP:一个通信网络管理专家系统外壳的设计与实现

本文介绍了笔者为开发名为OONMES的网络管理专家系统所实现的一个简单专家系统工具SIM-LISP。SIM-LISP是一个用C/C++语言来实现的模拟LISP语言的可调用函数集,它短小精巧,速度快,可以完成针对网管专家系统的事实或规则知识的表示、匹配、合一和推理等基本操作,并有与知识对象的连接功能,是网管专家系统内核实现的支撑环境。     

Helping hands: external support for the KNU insurgency in Burma

This article analyses to what extent the Burmese KNU insurgency made use of external support from states, refugees, and diasporas. Based on extensive fieldwork it is concluded that support from neighbouring states and refugees has for years kept the Karen rebellion alive. Western countries perceived forms of resistance to the illegitimate Burmese regime as just and have therefore played a crucial role in the continuation of conflict in Karen State. It is important that policymakers and donors as well as executing organizations continue to reflect critically on the way they exercise their work.     

Al Qaida on the US invasion of Afghanistan in their own words

This article consists of selected translations from captured interviews and dairies of Al Qaida members. The time period covered is from mid-2001 to early 2002 and concerns their operations in Afghanistan. The material clearly conveys a range of emotion, from confident to despondent, as well as efforts to contest the US actions. The first several pages give the reader context and some possible “lessons learned,” but the story(ies) are best told by the Al Qaida members themselves. All names are pseudonyms.     

基于GTST-DMLD-ESD的装备RMS建模仿真

装备的RMS是装备的重要设计参数,是影响战备完好和保障能力的关键因素.引入GTST-DMLD作为主要建模工具,建立起装备系统的RMS描述模型,以ESD为补充和扩展,对维修过程进行建模.并以GTST-DMLD-ESD模型作为装备RMS仿真的核心,对装备RMS仿真模型的总体框架进行了研究,并对各模块进行了较为详细的探讨.