SpaceWire网络混合路由机制设计

针对星上系统总线多元性导致的星载网络接口和协议不能标准化的发展瓶颈,基于SpaceWire总线协议,通过将静态路由(时间触发)与动态路由(事件触发)机制结合,实现了控制数据和载荷数据共用网络。静态路由完全遵循SpaceWire-D协议,在保证确定性传输的同时,通过启发式调度算法首次实现了多时间窗并行调度,并提出利用最大公约数法设计时间窗,以提高网络吞吐量;动态路由通过对随机事件和载荷数据分配优先级,实现传输路径冲突时对紧急任务的优先处理。在OPENT中搭建网络系统仿真模型,对所提出的路由机制进行了仿真。实验结果表明,静态路由时段网络吞吐量较现有调度算法有明显提高,动态路由实现了紧急事件优先传输。     

菜籽油基防锈润滑添加剂的制备及性能研究

菜籽油基添加剂是一种可生物降解的环保的润滑剂。水基润滑剂具有导热性好,成本低廉等优点。利用菜籽油制备了一种具有良好润滑性、极压性、防锈性及表面活性的多效水溶性润滑添加剂。此添加剂生物降解性好,制备过程中无废物及污染物产生,具有很好的环保效果。     

The Production and Deposition of the Guisborough Helmet

In September 1878 the British Museum received a donation of a folded metal plate which had been embossed and gilded. Restoration of the object revealed that the folded plate was in fact the outer casing of a Roman copper alloy cavalry sports type helmet which dates to the late second or third century AD. The story of what became known as the Guisborough helmet began 14 years earlier in what was then the North Riding of Yorkshire when workers employed by the Cleveland Railway Company discovered a ‘very curious plate of metal’ during road construction. It appears that the helmet was deliberately prepared for deposition and buried at a depth of c30 cm close to a stream. Examination by the authors suggests that this was a high value item that had been repaired many times. Experimental evidence suggests that the decoration alone required approximately 16 h to fashion.     

“It would be impossible to estimate the value of these works...” Mass Production at Springfield Armory during the American Civil War

The U.S. Armory in Springfield, Massachusetts, rarely appears in Civil War histories except perhaps as an unexplained statistical wonder. By late 1863, the Armory was the largest single supplier of rifles to Union forces. Springfield Armory workers out-produced over thirty American contractors, making more Army rifles at less cost while providing contractors with gauges, inspectors, and models, even though there were significant wartime private-sector mechanical innovations. This article identifies and explains the factors in the Armory’s success, provides context on contemporary American arms production and rifle models, and argues that the Armory’s methods and performance were among the first if not the first example of mass production in American small arms manufacture. The relative brevity of the Civil War episode, and the fact that it was not repeated in any comparable way at the Armory until World War II, has obscured its significance in American manufacturing history.     

低速率移动自组织网络安全路由协议

由于移动Ad Hoc网络具有无需基础设施,可以快速部署,很难完全被摧毁等优点,被作为数字化战场通信的优先选择,设计实现了一种适用于低速率移动Ad Hoc网络的安全路由协议——LSRP,它适用于分层架构的低速移动电台自组网,可以在网络资源有限的情况下,防御来自外部和内部两方面的攻击。LSRP协议利用分布式门限RSA签名方案来阻止非授权接入,防范来自网络外部的攻击;利用邻节点信任度评估机制,进行恶意节点检测和剪除,防范来自网络内部的攻击,增强了网络的安全性。     

Arms export controls and emerging domestic producers†

The possibility of domestic production raises a difficulty for arms export control measures, since embargoes, by raising the effective price of imports, increase the incentive for domestic production. We address this issue by developing a partial equilibrium model of the international arms market We compare three arms export regimes involving the exporters of high‐technology arms, with a particular focus on the effect of emerging domestic production: laissez‐faire trade, the uncoordinated regulation of exports and a producer cartel consisting of coordinated regulation. The main conclusion is that the possibility of domestic production significantly changes the nature of these stylized export regimes.     

Arms trade,arms control,and security: Collective action issues

This article puts forth collection action as a unifying theme for the conference essays on arms trade, control, and production. For each of these topics, collective action failures are related to group size and group composition considerations. Other issues are also examined including the manner in which individual contributions determine the overall level of the associated collective good ‐ the so‐called aggregation technology of public supply. Based on alternative aggregation technologies, the game‐theoretic underpinnings of these arms issues are explored.     

Asymptotic analysis of periodic policies for the inventory routing problem

In this article, a distribution system is studied where the sum of transportation and inventory costs is to be minimized. The inventory holding cost is assumed to be the same for all retailers. A fixed partition (FP) periodic policy is proposed with tight asymptotic worst‐case performance of 3/2 with respect to the best possible policy. This bound cannot be improved in the class of FP periodic policies. In partition‐based PB policies, the retailers are first partitioned into sets and then the sets are grouped in such a way that sets of retailers within a group are served together at selected times. A PB periodic, policy is presented with tight worst‐case asymptotic performance of with respect to the best possible policy. This latter performance improves the worst‐case asymptotic performance of of the previously best known policy for this problem. We also show that the proposed PB periodic policy has the best worst‐case asymptotic performance within the class of PB policies. Finally, practical heuristics inspired by the analyzed policies are designed and tested. The asymptotic worst–case performances of the heuristics are shown to be the same of those of the analyzed policies. Computational results show that the heuristics suggested are less than 6.4% on average from a lower bound on the optimal cost when 50 or more retailers are involved. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 00: 000–000, 2013     

Review of the ordered and proportionate flow shop scheduling research

Ordered flow shop models have appeared in the literature since the mid‐1970s and proportionate flow shop models have appeared since the early 1980s. We provide a detailed review of these models along with some analysis and potential topics for future research. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2013     

运用动态规划的智能卫星集群星间通信路由算法

通过建立智能卫星集群网络模型,把智能卫星集群星间通信路由问题转换为时延最短路径问题,进而提出一种求解此问题的智能卫星集群星间通信路由算法.该路由算法采用动态规划策略分阶段规划智能卫星集群两个成员之间的星间通信路由,在每个规划阶段,负责发送数据的智能卫星自主调用一种星间通信路由静态规划算法,以求出其在当前时刻的后继卫星来...