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761.
    
Since the end of the Cold War, a huge debate over how war has been changing has emerged; a common feature is that modern conflicts are not state vs. state wars, but ‘irregular wars’. In order to better understand modern irregular warfare, it is important to analyse past authors and ideas. Carlo Bianco’s concept of Guerra per bande highlights elements of mobility with different cooperating units, of terror, and of complex terrain. The present study offers the first English analysis of Carlo Bianco and underlines the similarities of his work to the hybrid warfare concept.  相似文献   
762.
    
This article investigates how US national security planners have envisioned the emerging strategic environment during the early twenty-first century and evaluates how their perceptions of this strategic environment have changed during these years. This conceptual evolution can be seen in how defense planners define threats, identify defense priorities, and design security strategies. Five key strategic planning documents serve as the basis for this analysis and illustrate significant shifts in how the US government has envisioned its own security requirements as well as the context within which its strategic vision will need to be realized. These planning documents are: (1) Joint Vision 2020, (2) the Bush Administration's 2002 National Security Strategy of the United States, (3) the Obama Administration's 2010 National Security Strategy, (4) US Strategic Defense Guidance entitled Sustaining US Global Leadership: Priorities for 21st Century Defense, and (5) the US Chairman of the Joint Chiefs of Staff's Capstone Concept for Joint Operations: Joint Force 2020.  相似文献   
763.
764.
    
The cyclic best‐first search (CBFS) strategy is a recent search strategy that has been successfully applied to branch‐and‐bound algorithms in a number of different settings. CBFS is a modification of best‐first search (BFS) that places search tree subproblems into contours which are collections of subproblems grouped in some way, and repeatedly cycles through all non‐empty contours, selecting one subproblem to explore from each. In this article, the theoretical properties of CBFS are analyzed for the first time. CBFS is proved to be a generalization of all other search strategies by using a contour definition that explores the same sequence of subproblems as any other search strategy. Further, a bound is proved between the number of subproblems explored by BFS and the number of children generated by CBFS, given a fixed branching strategy and set of pruning rules. Finally, a discussion of heuristic contour‐labeling functions is provided, and proof‐of‐concept computational results for mixed‐integer programming problems from the MIPLIB 2010 database are shown. © 2017 Wiley Periodicals, Inc. Naval Research Logistics, 64: 64–82, 2017  相似文献   
765.
    
We study a multi‐stage dynamic assignment interdiction (DAI) game in which two agents, a user and an attacker, compete in the underlying bipartite assignment graph. The user wishes to assign a set of tasks at the minimum cost, and the attacker seeks to interdict a subset of arcs to maximize the user's objective. The user assigns exactly one task per stage, and the assignment costs and interdiction impacts vary across stages. Before any stage commences in the game, the attacker can interdict arcs subject to a cardinality constraint. An interdicted arc can still be used by the user, but at an increased assignment cost. The goal is to find an optimal sequence of assignments, coupled with the attacker's optimal interdiction strategy. We prove that this problem is strongly NP‐hard, even when the attacker can interdict only one arc. We propose an exact exponential‐state dynamic‐programming algorithm for this problem as well as lower and upper bounds on the optimal objective function value. Our bounds are based on classical interdiction and robust optimization models, and on variations of the DAI game. We examine the efficiency of our algorithms and the quality of our bounds on a set of randomly generated instances. © 2017 Wiley Periodicals, Inc. Naval Research Logistics 64: 373–387, 2017  相似文献   
766.
The term “Gray Zone” is gaining in popularity as a way of describing contemporary security challenges. This article describes the “short-of-war” strategies – the fait accompli, proxy warfare, and the exploitation of ambiguous deterrence situations, i.e. “salami tactics” – that are captured by the term and offers several explanations for why state and non-state actors are drawn to these strategies. The analysis highlights why defense postures based on deterrence are especially vulnerable to the short-of-war strategies that populate the “Gray Zone.” The article concludes by suggesting how defense officials might adapt defense policies to life in the “Gray Zone.”  相似文献   
767.
    
This paper examines the ongoing expansion of China’s maritime power in the Indian Ocean region and analyses its potential impact on the extant balance of Sino-Indian maritime power in the region. It posits that the expanding Chinese maritime power in the Indian Ocean could seriously challenge India’s geostrategic advantage in the near future and that India can no longer take for granted its strategic location at the centre of the Indian Ocean nor the strength of its historical ties with the various regional states. It further argues that the current Indian maritime strategy for the Indian Ocean region, to be the “net security provider” for the entire region, is unsustainable and thus needs to be reviewed and rebuilt leveraging the geographic advantage enjoyed by India over China in the Indian Ocean.  相似文献   
768.
曹庭 《国防科技》2017,38(4):063-067
2016年年初以来,朝鲜先后进行了第四次、第五次核试验,在此背景下,韩国国防部宣布,韩美同意在韩国部署末段高空区域防御系统——\"萨德\"导弹防御系统,朝鲜半岛地区风云再起。美韩此举使原本不安的东北亚局势更加紧张,诱发并恶化着东北亚地区大国家间潜存的\"安全困境\"。韩国决定部署\"萨德\"不仅严重僵化了中韩的国际关系,使得原本对峙局面下的朝韩两国局势更加紧张,更破坏了东北亚军事战略均衡,地区\"新冷战\"格局逐步形成。  相似文献   
769.
    
Ten years of counterinsurgency in Iraq and Afghanistan have produced little in Britain's national interest. This article examines the political objectives set in these wars and the reasons why they have proved elusive. The core foreign policy aim was to sustain Britain's position as a great power by assuming responsibility for global order. Alliances with the United States and NATO would be the diplomatic tool for pursuing this aim. These alliances brought obligations, in the shape of agreed common threats. Rogue regimes with weapons of mass destruction and international terrorists harboured in failed states were deemed the primary threats to British security. Military means were therefore used in Iraq and Afghanistan to attack them. Whether Tony Blair's vision of global order ever made sense is debatable, and it attracted scepticism from the outset. The article argues experience in Iraq and Afghanistan showed that a strategy to eliminate terrorism (the WMD threat turned out never to have existed) by expeditionary counterinsurgency could only fail. Therefore the attention lavished on operational-level performance by most studies is misplaced, because no amount of warfighting excellence could make up for strategic incoherence. Finally, the article proposes the more important question arising from the last ten years is why the UK pursued a futile strategy for so long. The difficulties associated with interpreting events, a malfunctioning strategic apparatus, weak political oversight, and bureaucratic self-interest are posited as the most significant explanations.  相似文献   
770.
    
In September 2011, the Commander of the International Security Assistance Force (ISAF) in Afghanistan directed the Afghan Assessment Group to redesign the way in which ISAF was assessing the status of the war, and to be ‘revolutionary’ in so doing. The resulting assessment paradigm was novel, non-doctrinal, and effectively addressed the unique complexities of the counterinsurgency in Afghanistan and the needs of the ISAF Commander. It had a two-tier structure consisting of both strategic and campaign assessments. The former focused on answering a set of strategic questions in narrative, analytic form to address the strategic environment, while the latter used a set of standards and accompanying narrative responses to gauge accomplishment of campaign tasks. Both tiers captured the current state of the war while maintaining an eye on future challenges and opportunities. The two assessments and their associated processes were designed to stimulate discussions leading directly to decisions by senior leaders on actions they could take, direct, or request. While any assessment paradigm will have advantages and disadvantages, an examination of the pros and cons of this assessment paradigm makes clear that it should be considered a ‘best practice’ in the field of counterinsurgency assessment.  相似文献   
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