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301.
针对分布式放大前传中继辅助多用户对等通信系统研究了存在非理想信道状态信息(CSI)时的分布式中继网络(DRN)鲁棒波束成形设计问题。采用统计CSI误差模型,考虑了两种鲁棒优化问题:一是从公平性的角度出发在DRN总发送功率约束下实现多个目的节点间的信干噪比(SINR)平衡;另一是从有效性的角度出发在保证各个目的节点服务质量需求(SINR大于预设门限)约束下最小化DRN总发送功率。对问题的分析和建模表明,在多用户情况下,这两个问题都是难以求解的优化问题。通过引入半定松弛(SDR)思想,将上述两种优化问题转化为可利用内点法有效求解的半定规划(SDP)问题。最后通过仿真验证了所提设计的鲁棒性能。 相似文献
302.
Gaetano Joe Ilardi 《Small Wars & Insurgencies》2013,24(2):331-358
This article will seek to provide a detailed examination of the IRA's operational intelligence methodologies. Providing not only a lengthy discussion on the organization's intelligence collection protocols, it will also examine the interplay between intelligence and IRA decision-making. It will be contended that intelligence's influence resided in its ability to introduce a strong element of predictability into the IRA's decision-making process. This depended on an ability to construct a detailed intelligence picture of the target and its geographical milieu so as to minimize the likelihood of volunteers encountering unforeseen circumstances that could adversely affect planned or anticipated outcomes. 相似文献
303.
Geraint Hughes 《Small Wars & Insurgencies》2013,24(4):561-590
This article examines the use of specialised plain-clothes military units in counter-terrorism, concentrating on examples involving liberal-democratic states. It analyses the benefits and problems arising from clandestine military activity, focusing in particular on British army units (notably 14 Intelligence Company and the Force Research Unit in Northern Ireland). The article concludes by arguing that such formations have a clear utility – notably in gathering intelligence on terrorist groups – but other aspects of their role are inherently controversial (notably in cases where undercover soldiers use deadly force against suspected terrorists). It also states that plain-clothes military operations need to be conducted on the basis of accountability, both for strategic reasons, and also in accordance with the norms of liberal democracy. 相似文献
304.
Stephen D. Davis 《Small Wars & Insurgencies》2013,24(1):49-71
US military operations are increasingly conducted within urban environments and with these operations come the risk of increasing the number of civilian casualties and infrastructure damage. The use of non-lethal weaponry, such as directed-energy weapons, is one method for minimizing collateral damage. This method enables US military forces to effectively fight within urban environments through force escalation capabilities. Using a series of historical examples and future scenarios for urban warfare, this article highlights deficiencies affecting military capabilities in military urban operations, addresses the consequences of collateral damage, assesses the effectiveness of directed-energy weapons in military urban operations and encourages further funding, research and integration of non-lethal weaponry, such as directed-energy weapons, within the US military. 相似文献
305.
Victor Chidubem Iwuoha 《African Security Review》2013,22(1):38-55
ABSTRACTDecade-long security cooperation and counterterrorism engagements in Nigeria have failed to bring down Boko Haram or at least weaken its terrorist structures and transnational spread. I argue that disconnects between counterterrorism-assistance seeking states and their superpower sponsors are implicated in the intractability of Boko Haram's insurgency in Nigeria. Why is the U.S. counterterrorism intervention to individual MNJTF countries (i.e. troop contribution, military funding and intelligence support) ‘lopsided’, ‘fragmented’ and ‘unevenly distributed;’ and how are these implicated in the fight against Boko Haram terrorism? This has impacted negatively on MNJTF countries – lack of cooperation, divisiveness and individualism in coordinating and forging offensives against Boko Haram. These concerns interface several blind spots in the picture of external influences on military’s approach to Boko Haram. I elicit primary data from top military officers. I conclude by predicting the implications and consequences of these counterterrorism complexities, and their potency to defeat or encourage Boko Haram terror. 相似文献
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308.
This paper empirically investigates the importance of financial and political variables in determining debt rescheduling probabilities in Turkey for 1955–2000. The problem of sovereign debt default and rescheduling has been the subject of substantial academic research during the last two decades. There has been criticism of models of developing countries’ indebtedness and rescheduling that rely solely on some economic or financial predictors related to country debt, the foreign exchange sector or the domestic economic situation. Using probit analysis, this paper indicates that financial variables are important determinants of rescheduling probabilities. However, political variables are not significant in our models. 相似文献
309.
This paper models transnational terrorism as a three‐way strategic interaction involving a government that faces armed opposition at home, which may spill over in the form of acts of terrorism by the state's opponents against the government's external sponsor. The external sponsor also utilises deterrence against potential terrorists, which only lowers terrorism if terrorists are not intrinsically motivated by a deep‐seated sense of humiliation. The model highlights the importance of intrinsic motivation. A rise in the external power's preference for deterrence against terrorism may backfire in these circumstances. Increases in the government's military efficiency against the rebels, who are also terrorists against the government's sponsor, raises overall levels of violence. 相似文献
310.