基于小生境遗传算法的相控阵雷达任务调度

针对密集目标环境下相控阵雷达任务调度问题,分析了相控阵雷达工作任务特点、调度流程以及资源约束,建立了资源约束条件下的相控阵雷达调度模型。研究了传统遗传算法在相控阵雷达任务调度中收敛速度慢和早熟问题,提出了基于共享机制的自适应小生境技术的改进方法。仿真结果表明,基于小生境遗传算法的相控阵雷达任务调度方法能够有效地提高任务调度成功率,降低截止期错失率。     

带时间窗的相控阵雷达实时任务调度方法

为了解决传统相控阵雷达任务调度中采用基于工作方式优先级的方法而存在忽略任务时间紧迫性和重要性的问题,提出了一种基于任务自身工作方式优先级、截止期和空闲时间3个特征参数的相控阵雷达任务调度方法,通过调整参数的权重来适应调度器不同的负载情况,并采用时间窗处理发生冲突的任务请求,确保更多的高优先级任务在调度间隔内被调度。仿真结果表明,所提出的方法能够有效提高任务的调度成功率,明显改善调度器性能。     

基于最小时间窗的多功能雷达调度算法研究

雷达、电子战、通信等多功能电子系统一体化是雷达的发展方向之一,针对多功能雷达的资源管理与调度,基于孔径分割建立了多功能雷达系统的任务模型,根据任务作用距离确定了任务事件对孔径资源的占用率,并在此基础上给出了一种基于最小时间窗调度间隔的任务调度算法来解决多功能雷达的任务调度问题,通过仿真验证,证明该算法具有一定的有效性.     

相控阵雷达协同探测任务调度研究北大核心

针对相控阵雷达协同探测资源调度问题,提出了一种协同探测任务调度算法。首先介绍了相控阵雷达协同探测相关内容;接着给出了协同探测调度模型。针对多节点协同探测,提出一种优化模型,权衡时间偏移量和时间利用率2个因素,在不显著增大时间偏移量的前提下,提高时间利用率,提升探测性能。最后通过仿真验证了算法的有效性。     

相控阵雷达协同探测任务调度研究

针对相控阵雷达协同探测资源调度问题,提出了一种协同探测任务调度算法。首先介绍了相控阵雷达协同探测相关内容;接着给出了协同探测调度模型。针对多节点协同探测,提出一种优化模型,权衡时间偏移量和时间利用率2个因素,在不显著增大时间偏移量的前提下,提高时间利用率,提升探测性能。最后通过仿真验证了算法的有效性。     

基于目标威胁度的相控阵雷达自适应调度方法

对时间资源的合理安排是相控阵雷达发挥自身优势的关键。将目标威胁度引入调度算法中,与工作方式和任务截止期共同进行综合优先级规划。通过构建目标威胁度的量化模型,使雷达在调度跟踪任务时依目标威胁度大小分配时间。提出了修正价值率和执行威胁率的概念,完善了性能评估指标。通过仿真,全面评价了新算法性能,验证了引入目标威胁度的合理性。结果表明,新算法可以有效提升相控阵雷达对高威胁度目标的处理能力。     

一种基于反馈式结构的异步航迹融合算法

在实际的雷达网数据融合系统中,多数情况下各部雷达的采样时刻不同步,并且采样周期不一致,比如引导雷达和警戒雷达。本文提出了一种基于反馈式结构的异步航迹融合算法,即便在局部节点采样周期相差较大的情况下,仍能充分利用局部节点的信息。经仿真实验验证了该算法的优越性。     

改进遗传算法的相控阵雷达自适应调度算法及仿真

多功能相控阵雷达因其阵列天线的波束捷变能力,可执行对多个目标交替搜索、验证、跟踪等任务,而如何在时间约束下分配任务,对雷达性能有着决定性的影响。使用一种有效的调度算法能够使雷达资源合理分配,能够让雷达整体性能优化。在分析自适应调度算法的设计原则基础上,给出了具体的性能评估指标。针对多功能相控阵雷达,改进了传统的遗传算法作为调度算法。算法能够在雷达调度间隔约束下,选择综合效能最好的方案安排一个调度间隔内的雷达事件序列,并通过仿真结果验证了算法的有效性。     

多核系统中基于动态松弛时间回收的节能实时调度算法

许多嵌入式实时任务的实际执行时间往往小于最坏情况执行时间,因此可以产生大量的动态松弛时间.针对时限等于周期的偶发任务集,提出一种基于动态松弛时间回收的多核系统节能实时调度算法LRE-DVFS-ALL.该算法基于最优在线调度算法LRE-TL,利用TL面内节能实时调度思想,在每个TL面的提前完成时刻实现动态松弛时间回收,降...     

综合优先级的被动雷达任务自适应调度算法

综合考虑影响威胁度的5个参数,给出辐射源威胁度评估准则与方法。将辐射源威胁度参数融入被动雷达任务优先级的设计中,提出一种综合优先级算法(HTHPEDF),根据辐射源威胁度动态地调整任务优先级。运用该综合优先级算法实现任务自适应调度,设计调度收益与调度代价的评价函数。通过仿真验证了算法的有效性,该算法以较低的调度代价获得较高的调度收益,可有效提升任务综合调度能力。     

Putin – the masked nemesis of the strategy of ambiguity

Recent events demonstrate the complex and adaptive approach employed by Russia to reassert influence in Europe. The changing face of Russia’s strategy commenced in 2007 when it launched a crippling cyber-attack against Estonia. This was followed by a large Russian conventional attack against Georgia in 2008, occupying two large areas of the nation. 2014 witnessed the Russian annexation of Crimea where in just a week, Russia seized control of Crimea “without firing a shot.” The annexation of Crimea was rapidly followed by a Russian inspired and led subversive war in eastern Ukraine. The common thread among these diverse Russian operations is its use of ambiguity to confound and confuse decision makers in the West.     

India's counter-insurgency experience: the ‘trust and nurture’ strategy

The Indian Army, a force trained primarily for conventional warfare, has been engaged in internal counter-insurgency operations since the 1950s. Despite such a long innings on a counter-insurgency mode, little attention has been accorded within military circles to doctrinal innovation for waging sub-conventional warfare in India's democratic political context. At best, the Army continues to view counter-insurgency duty as secondary to its primary duty of defending India from external conventional threats. By conceptualizing a counter-insurgency strategy of ‘trust and nurture’, this article aims to fill this critical doctrinal gap in India's military policy. The author argues that a counter-insurgency strategy of ‘trust and nurture’ based on democratic political culture, measured military methods, special counter-insurgency forces, local social and cultural awareness and an integrative nation-building approach will result in positive handling of India's internal security problems. The author utilizes India's counter-insurgency experiences in Assam, Mizoram, Nagaland, Punjab, and Operation ‘Sadhbhavana’ in Jammu and Kashmir as illustrative empirical indicants in order to validate the ‘trust and nurture’ strategy.     

An Unlikely Alliance: Portuguese and South African Airpower in Angola, 1968–1974

The war that Portugal was obliged to fight in Africa began in 1961 and immediately stretched the resources of its armed forces. Nowhere was this thinness more apparent than in policing the vast territory of Angola. The east and southeast of Angola were particularly vulnerable, as the area was a vast, sparsely populated region characterised by enormous featureless plains or chanas covered in tall grass and broken by an extensive river system and mountainous forests. The only military solution to policing these immense spaces was aviation and specifically the helicopter that could carry troops into battle, protect them with a gunship and bring them home when the operation was concluded. The immediate problem for the Portuguese Air Force (Força Aérea Portuguesa or FAP) in Angola and elsewhere was a scarcity of helicopters. The solution was an alliance with South Africa, which had a strong inventory of Alouette IIIs, to help in policing the east. This move was likewise in the interest of South Africa, as its threat came from Zambia through south-eastern Angola. This article examines the strategic and tactical development of this unusual, cross-cultural alliance and the symbiotic relationship that resulted in destruction of the enemies of both in Angola.     

国内外结构钢焊条研究的现状与发展

本文主要介绍了国外焊条的现状和发展趋势,包括焊条的高韧性、高效率、低尘低毒和耐吸潮性能,为国内的焊条研究提供了参考依据。     

A Sign of Victory?: ‘Scottish Swords’ and Other Weapons in the Possession of the ‘Auld Innemie’

Many late medieval documents, notably inventories of arms and armour, of Englishmen contain references to ‘Scottish swords’ and other weapons. What did the compilers of these documents mean when they described a weapon as ‘Scottish’? How did such weapons come to be in the possession of these men? This article will attempt to explain this phenomenon drawing on primary documentary sources and surviving material culture from Glasgow Museums’ collections and others, as well as artworks from the period.     

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).     

Cyberpower in Strategic Affairs: Neither Unthinkable nor Blessed

Abstract

This article explores the effect of connectivity on strategic affairs. It argues that the effect on war's character is potentially, although not yet shown in practice, considerably large. Its effect upon the distribution of power among states in the international system is small, contrary to the claims of ‘cyberwar’ alarmists. All told, however, its effect upon strategic affairs is complex. On the one hand, it represents a significant advance in the ‘complexification’ of state strategies, understood in the sense of the production of intended effects. On the other hand, strategists today – still predominantly concerned with the conflicts and confrontations of states and organised military power – are generally missing the power which non-traditional strategic actors, better adapted to the network flows of the information age, are beginning to deploy. These new forms of organization and coercion will challenge the status quo.