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901.
Abdurrahim Sıradağ 《African Security Review》2013,22(3-4):308-325
ABSTRACTTurkey has maintained its strategic relations with Africa at the highest level under recent AK Party governments in the field not only of low politics but also of high politics. For example, it opened its largest overseas military base in Somalia in 2017 and signed military, defense and security pacts with more than 25 African countries. This article traces the deep historical and cultural relations with Africa behind its newly evolving foreign policy identity, arguing that its booming economic power has been a significant driving force in shaping a new security strategy. It examines what the growing security involvement means for both Turkey and Africa in order to contribute to the relevant literature through a holistic approach from both theoretical and conceptual perspectives. 相似文献
902.
Nancy W. Gallagher 《The Nonproliferation Review》2013,20(3-4):469-498
ABSTRACTSince the end of the Cold War, arms control proponents tried to make the case for deep nuclear reductions and other forms of security cooperation as necessary for strategic stability. While different versions of strategic stability analysis did sometimes produce innovative proposals, constructive negotiations, and successful ratification campaigns in the past, this analytical framework has become more of a hindrance than a help. Treating arms control as a predominantly technical way to make deterrence more stable by changing force structure characteristics, military operations, relative numbers of weapons on either side, or total number of nuclear weapons gives short shrift to political factors, including the fundamental assumptions about world politics that inform different arms control logics, the quality of political relations among leading states, and the political processes that affect negotiation, ratification, and implementation. This article compares two logics for arms control as a means to enhance strategic stability, one developed by the Cambridge community in the 1960s and one used by the Reagan administration and its successors, with current perspectives on strategic stability in which flexibility and freedom of action are preferable to predictability and arms control. It also contrasts what the Barack Obama administration has tried to achieve through strategic stability dialogues with Russia and China with how they envision security cooperation. It then presents an approach developed during the Cold War by Hedley Bull for thinking about both the technical and the political dimensions of arms control, and suggests that the logic of Cooperative Security (which shares important features with Bull's approach) is a more appropriate and productive way to think about arms control in the twenty-first century than strategic stability analysis is. 相似文献
903.
In this article, we study deterministic dynamic lot‐sizing problems with a service‐level constraint on the total number of periods in which backlogs can occur over a finite planning horizon. We give a natural mixed integer programming formulation for the single item problem (LS‐SL‐I) and study the structure of its solution. We show that an optimal solution to this problem can be found in \begin{align*}\mathcal O(n^2\kappa)\end{align*} time, where n is the planning horizon and \begin{align*}\kappa=\mathcal O(n)\end{align*} is the maximum number of periods in which demand can be backlogged. Using the proposed shortest path algorithms, we develop alternative tight extended formulations for LS‐SL‐I and one of its relaxations, which we refer to as uncapacitated lot sizing with setups for stocks and backlogs. {We show that this relaxation also appears as a substructure in a lot‐sizing problem which limits the total amount of a period's demand met from a later period, across all periods.} We report computational results that compare the natural and extended formulations on multi‐item service‐level constrained instances. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
904.
J. Thomas Moriarty 《Small Wars & Insurgencies》2013,24(3):476-497
The purpose of this paper is to provide a better conceptualization of insurgent strategies. Specifically, I shall examine Che Guevara's ‘Foco’ theory of insurgency, as it is one of the most theoretically popular and most pervasive strategies of insurgency currently practiced throughout the world. After briefly examining the origins, objectives, and theoretical strengths of the Foco theory (also known as the Vanguard Theory), I will argue that Guevara's theory suffers from an internal tension that I term the ‘Vanguard's Dilemma’. The significance of this dilemma creates a tension within the Vanguard Theory that can be fatal for insurgents if properly exploited by counterinsurgent operations. This paper will examine in detail this dilemma and show how it can be exploited. Given that several insurgent groups within Iraq and Afghanistan currently adhere to the Vanguard Theory of insurgency, a proper understanding of this insurgent strategy is an essential first step in the long road towards confronting and winning asymmetrical conflicts. 相似文献
905.
Stephen Pampinella 《Small Wars & Insurgencies》2013,24(5):721-743
As US counterinsurgency campaigns draw to a close, doctrine for asymmetric warfare written during the War on Terror has come under heavy criticism. While many have argued that this shift to ‘winning hearts and minds’ is evidence that the United States is taking humanitarianism and nation-building seriously, others argue that a wide gap exists between US counterinsurgency doctrine and the protection of civilians afflicted by conflict. In this article, I show that the latter is true by comparing theories of instrumental and communicative action to US doctrine for operational design, stability operations, and counterinsurgency. I argue that these texts treat the people as an object to be manipulated for the achievement of pre-determined self-interested strategic goals rather than members of a community that jointly designs operations to fulfill shared objectives. However, US doctrine does contain communicative elements that, if prioritized, would better support humanitarian and state-building objectives otherwise subordinated in the War on Terror. 相似文献
906.
GNSS(全球卫星导航系统)授时接收机利用卫星导航信号获取钟差并校准本地时钟,从而与GNSS系统时间同步。提出了全新的基于锁相环的GNSS授时接收机钟差校准算法,将钟差校准过程等效为传统的锁相环模型,鉴相器的功能由PVT(位置、速度与时间)解算实现,压控振荡器的功能由本地时间调整接口实现,环路将本地秒相位与GNSS系统的秒相位锁定。分析了环路总误差的组成,以及环路参数与各误差项的关系,给出了误差最小的环路优化设计准则。在北斗二号卫星导航接收机平台上进行了对比实验,验证了算法的有效性。 相似文献
907.
为使单电子晶体管达到实际应用的地步,开展室温条件下相关研究成为必然。从正统理论出发,推导、计算出室温条件下单电子晶体管能否正常工作的库仑岛临界尺寸:存储器件为6.5nm,逻辑器件为1.5nm;本文还推导和计算出单电子晶体管室温下发生能量量子化效应的临界尺寸:4.7nm,并对这3种临界尺寸进行了验证和分析。另外,通过比较分析本文还得出了室温条件下,所有逻辑器件均必须考虑能量量子化效应,所有存储器件应尽量考虑能量量子化效应的结论。分析结果表明,库仑岛临界尺寸的确定对单电子晶体管的实际应用具有重要意义。 相似文献
908.
为在复杂环境中对目标进行长时间精确跟踪,提出一种尺度自适应特征压缩跟踪算法。通过结构约束性采样,获取不同尺度不同位置的扫描窗,离线计算不同尺度下的稀疏随机感知矩阵。在线跟踪时利用这些矩阵感知对应尺度的图像采样块,实现特征降维,提高运算速度。利用朴素贝叶斯分类器对降维特征判决,在线学习更新分类器参数,找出具有最高分类得分的采样块作为新的跟踪结果,实现跟踪位置及尺度的自适应更新。实验结果表明,该算法能适应目标的基本姿态变化及尺度缩放,不依赖于目标初始跟踪区域尺度选取,跟踪结果具有较强的鲁棒性。 相似文献
909.
910.