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861.
This study considers the block relocation and loading problem in container terminals. The optimal loading sequence and relocation location are simultaneously decided on the basis of the desired ship‐bay and initial yard space configuration. An integer linear programming model is developed to minimize the number of relocations in the yard space on the basis of no shifts in the ship bay. The accuracy of the model is tested on small‐scale scenarios by using CPLEX. Considering the problem size in the real world, we present a rule‐based heuristic method that is combined with a mathematical model for the removal, loading, and relocation operations. The influence of rules on algorithm performance is also analyzed, and the heuristic algorithm is compared with different types of algorithms in the literature. The extensive numerical experiments show the efficiency of the proposed heuristic algorithm. 相似文献
862.
Colin D. Robinson 《Defense & Security Analysis》2019,35(4):423-429
ABSTRACTBagayoko, Hutchful, and Luckham correctly argue that the structures, characteristics, and operating methods of official security institutions in Africa have been somewhat neglected, with a lack of much recent research. The Somali National Army (SNA) sits among these lacunae. Its formal structures can be used as a skeletal starting point and springboard to start to draw the network diagrams that chart informal linkages. This is why recent declassification decisions by U.S. intelligence bodies, coupled with period documents released to the UK National Archives, hold significance in helping us understand early hierarchical SNA arrangements. They show the steady build-up in size of the force, to 1987, to about the time the civil war began to fragment the state. 相似文献
863.
This article investigates how strategic culture influenced the decision-making of Australia and Poland regarding the global coalition against the Islamic State. In the coalition, Australia has followed its tradition of active participation in United States-led operations, while Poland has embarked on a more cautious line, thereby breaking with its previous policy of active participation. The article examines how Australian and Polish responses to the coalition were shaped by five cultural elements: dominant threat perception, core task of the armed forces, strategic partners, experiences of participating in coalitions of the willing, and approach to the international legality of expeditionary operations. It finds that Australia and Poland differed on all five elements but that the major differences are found in dominant threat perception and core task of the armed forces. 相似文献
864.
Murat Caliskan 《Defense & Security Analysis》2019,35(1):40-58
Hybrid warfare is the latest of the terms/concepts that have been used within the defence community in the last three decades to label contemporary warfare. It has been officially adopted in the core strategic documents of NATO, EU and national governments and has already inspired many articles, policy papers and books; however, this paper is unique in the sense that it analysis the hybrid warfare concept through the lens of strategic theory. It is argued that hybrid warfare does not merit the adoption as a doctrinal concept. Strategic theory instead, which lies at the nexus of all dimensions of warfare, provides a better viewpoint to approach contemporary warfare. It concludes that efforts should be directed towards exploring warfare under the light of eternal principles instead of proving the emergence of new types of warfare. 相似文献
865.
Caroline Varin 《African Security Review》2018,27(2):144-157
Since the 2003 war in Iraq, private military and security companies (PMSCs) have become increasingly legitimate actors in modern conflicts. Despite this normative shift, rumours in March 2015 regarding the use of South African mercenaries in Nigeria to combat Boko Haram insurgents caused an international outrage, while the Nigerian government remained nonchalantly silent on the matter. This article investigates the impact of mercenaries on the conflict in the last six months of the Jonathan government. Using primary and secondary qualitative research, it assesses the role that PMSCs played in Nigeria’s counterinsurgency strategy, along with the ensuing reaction of international and local media to the outsourcing of violence to foreign companies. The article concludes that – notwithstanding the improved image of PMSCs in the world, and the actual impact of the contractors on the Nigerian counterinsurgency effort – the stigma of mercenaries continues to plague the industry, particularly on the African continent. 相似文献
866.
867.
868.
The authors have over 50 years' experience of working on defence in Central and Eastern Europe. They have been intimately involved in trying to reform over 10 national defence organisations including Ukraine. During this work, they often faced intractable resistance and scepticism or conversely, apparent unbounded support, but following this, a complete lack of any actual implementation work by officials. This paper addresses some of the findings and observations identified by the authors that appear to cause these responses and the consequent failure of reform. A new research approach has been taken by using the business and culture tools from Schein, Hofstede and Kotter to try and unravel the underlying causality of that failure. The second part of the paper produces a new process for change based upon the research conclusions to help other advisers and consultants working on reform in the post communist defence arena. 相似文献
869.
We analyze an interdiction scenario where an interceptor attempts to catch an intruder as the intruder moves through the area of interest. A motivating example is the detection and interdiction of drug smuggling vessels in the Eastern Pacific and Caribbean. We study two models in this article. The first considers a nonstrategic target that moves through the area without taking evasive action to avoid the interdictor. We determine the optimal location the interceptor should position itself to best respond when a target arrives. The second model analyzes the strategic interaction between the interceptor and intruder using a Blotto approach. The intruder chooses a route to travel on and the interceptor chooses a route to patrol. We model the interaction as a two‐player game with a bilinear payoff function. We compute the optimal strategy for both players and examine several extensions. © 2017 Wiley Periodicals, Inc. Naval Research Logistics, 64: 29–40, 2017 相似文献
870.
Mark Malan 《African Security Review》2017,26(4):341-361
This essay recalls the immediate and longer-term responses of the US and its allies to the events of 9/11. It contends that the die for contemporary developments in transnational terrorism was cast in the immediate aftermath of 9/11 – in particular the launching of sustained ‘anti-terrorist’ military combat operations in Afghanistan and Iraq, and more covert ‘kinetic’ operations elsewhere in the Middle East and Africa. The essay seeks specifically to expose the counter-productivity of using military operations as the primary antidote to transnational terrorism. Focusing on the African ‘laboratory’ and the spread of transnational terrorism and Islamic militancy, particularly in West and East Africa, the essay concludes that radical Islamists have mastered the ‘battle of the narrative’ and that the Western penchant for dispensing a kinetic brand of medication is feeding rather than fighting the virus of global terrorism. 相似文献