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11.
Marc-Antoine Pérouse de Montclos 《Small Wars & Insurgencies》2013,24(5-6):863-885
ABSTRACTThis article discusses the shortcomings of the “de-radicalization doctrine” in sub-Saharan Africa. The issues raised are illustrated by the war against Boko Haram, which involves Nigeria, Niger, Chad and Cameroon. Relying on interviews with security officers, insurgents, civil servants, displaced people, humanitarian workers and Muslim and Christian clerics in Nigeria, Niger and Chad since 2005, the investigation shows that the four states focused on repression rather than demobilisation programs in prison or outdoors. The Boko Haram crisis is mainly a story of mismanagement. The article thus challenges the assumptions of the “de-radicalization doctrine” in Muslim Africa South of the Sahara. First, attempts to de-radicalize jihadi terrorists tend to focus too much on religious fanaticism and the exegesis of the Quran. Secondly, they are neither feasible nor efficient. Finally, they obscure priorities that are more important to counter extremism and demobilize insurgents. 相似文献
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An important aspect of supply chain management is dealing with demand and supply uncertainty. The uncertainty of future supply can be reduced if a company is able to obtain advance capacity information (ACI) about future supply/production capacity availability from its supplier. We address a periodic‐review inventory system under stochastic demand and stochastic limited supply, for which ACI is available. We show that the optimal ordering policy is a state‐dependent base‐stock policy characterized by a base‐stock level that is a function of ACI. We establish a link with inventory models that use advance demand information (ADI) by developing a capacitated inventory system with ADI, and we show that equivalence can only be set under a very specific and restrictive assumption, implying that ADI insights will not necessarily hold in the ACI environment. Our numerical results reveal several managerial insights. In particular, we show that ACI is most beneficial when there is sufficient flexibility to react to anticipated demand and supply capacity mismatches. Further, most of the benefits can be achieved with only limited future visibility. We also show that the system parameters affecting the value of ACI interact in a complex way and therefore need to be considered in an integrated manner. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011 相似文献
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Since the introduction of flexible manufacturing systems, researchers have investigated various planning and scheduling problems faced by the users of such systems. Several of these problems are not encountered in more classical production settings, and so‐called tool management problems appear to be among the more fundamental ones of these problems. Most tool management problems are hard to solve, so that numerous approximate solution techniques have been proposed to tackle them. In this paper, we investigate the quality of such algorithms by means of worst‐case analysis. We consider several polynomial‐time approximation algorithms described in the literature, and we show that all these algorithms exhibit rather poor worst‐case behavior. We also study the complexity of solving tool management problems approximately. In this respect, we investigate the interrelationships among tool management problems, as well as their relationships with other well‐known combinatorial problems such as the maximum clique problem or the set covering problem, and we prove several negative results on the approximability of various tool management problems. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 445–462, 1999 相似文献
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We consider a single-machine problem of scheduling n independent jobs to minimize makespan, in which the processing time of job Jj grows by wj with each time unit its start is delayed beyond a given common critical date d. This processing time is pj if Jj starts by d. We show that this problem is NP-hard, give a pseudopolynomial algorithm that runs in time and O(nd) space, and develop a branch-and-bound algorithm that solves instances with up to 100 jobs in a reasonable amount of time. We also introduce the case of bounded deterioration, where the processing time of a job grows no further if the job starts after a common maximum deterioration date D > d. For this case, we give two pseudopolynomial time algorithms: one runs in O(n2d(D − d) time and O(nd(D − d)) space, the other runs in pj)2) time and pj) space. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 511–523, 1998 相似文献
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Cedric de Coning 《Contemporary Security Policy》2017,38(1):145-160
When the United Nations (UN) Security Council needs to authorize a peace enforcement operation in Africa, its partner of choice is the African Union (AU). Africa has developed significant peace operations capacity over the past decade. In addition to deploying eight AU operations, Africa now contributes 50% of all UN peacekeepers. African stability operations, like its mission in Somalia, are often described as peace enforcement operations. In this article, I question whether it is accurate to categorize African stability operations as peace enforcement? I answer the question by considering what the criteria are that are used to differentiate between peace enforcement and peacekeeping operations in the UN context. I then use the peace enforcement criteria to assess whether AU stabilization operations would qualify as peace enforcement operations. In conclusion, I consider the implications of the findings for the strategic partnership between the AU and the UN. 相似文献
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建立了惰性气体中电爆丝爆炸激励的冲击波模型。对于冲击波马赫数与光辐射强度的关系、惰性气体种类对冲击波强度的影响以及电爆丝根数对冲击波强度的影响,进行了理论计算与分析,所得结论对红外脉冲强光辐射源的研究有重要作用。 相似文献
19.
Indra de Soysa 《Civil Wars》2016,18(1):1-24
Critics of globalisation suggest that growing free-market conditions generate anomie, leading ultimately to what some term ‘new wars’ and new insecurities. Others argue that liberal economies dissuade violence since people gain from peace. This study argues for a micro perspective that views predatory economic policies driving higher investment in rebellion-specific capital, such as shadow economic activity that easily translates into insurgency in weak-state settings. Investment in the shadows determines survivability against superior state forces, and survivability determines rebellion, by definition. Using civil war onset data from 1970 to 2013, as well as the Global Peace Index (GPI) and several of its individual components, which capture societal insecurity above and beyond the absence of armed violence, this study finds that countries that are more capitalistic have a lower risk of civil war and societal insecurity. The results are robust to alternative models, testing methods, and uphold when examining several relevant subcomponents of the index, such as internal conflict, violent crime, homicides, ease of access to small arms, and political instability. Surprisingly, democracy tends not to be associated with peace but associates with increased criminality whereas strong autocracy reduces it, suggesting that capitalism, more than democracy, associates with conditions favourable to societal security, independently of a country’s level of development. 相似文献
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Lieneke Eloff de Visser 《Small Wars & Insurgencies》2013,24(4):712-730
Efforts at winning hearts and minds (WHAM) impact on and are affected by perceptions of legitimacy. In the Namibian war for independence (1966–1989) efforts of the South African counterinsurgent forces at winning hearts and minds focused mainly on persuading the population to cooperate in exchange for material benefits and services. The article demonstrates that this successfully contributed to a dimension of legitimacy that is conceptualized as pragmatic legitimacy. However, other dimensions of legitimacy are identified in which the South Africans were lacking, that is in moral, legal, and identity-based legitimacy. Furthermore, in areas where control was contested and where the population could not be shielded from insurgent intimidation, it is argued that the effects of coercion outweighed legitimacy altogether. 相似文献