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371.
MARTIN R RUPIYA 《African Security Review》2013,22(1):83-89
Abstract This paper seeks to critically appraise Africa's position within the United Nations Security Council from the inception of the UN in 1945 until the end of 2010, spanning the entire history of the world body. A few factors make such an appraisal a useful exercise. These include the ongoing debates about the reform of the Council in particular and the UN as a whole, and the growing interest that many African students and observers of and actors in international relations seem to have developed in recent years in the working of the world body. In this appraisal, emphasis will be placed on the origin and rationale behind the establishment of the Security Council as well as the use of the veto power by its permanent members, with a special reference to Africa. 相似文献
372.
Tûba Aktaran‐Kalaycı Christos Alexopoulos Nilay Tanık Argon David Goldsman James R. Wilson 《海军后勤学研究》2007,54(4):397-410
We formulate exact expressions for the expected values of selected estimators of the variance parameter (that is, the sum of covariances at all lags) of a steady‐state simulation output process. Given in terms of the autocovariance function of the process, these expressions are derived for variance estimators based on the simulation analysis methods of nonoverlapping batch means, overlapping batch means, and standardized time series. Comparing estimator performance in a first‐order autoregressive process and the M/M/1 queue‐waiting‐time process, we find that certain standardized time series estimators outperform their competitors as the sample size becomes large. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
373.
We consider a manufacturer (i.e., a capacitated supplier) that produces to stock and has two classes of customers. The primary customer places orders at regular intervals of time for a random quantity, while the secondary customers request a single item at random times. At a predetermined time the manufacturer receives advance demand information regarding the order size of the primary customer. If the manufacturer is not able to fill the primary customer's demand, there is a penalty. On the other hand, serving the secondary customers results in additional profit; however, the manufacturer can refuse to serve the secondary customers in order to reserve inventory for the primary customer. We characterize the manufacturer's optimal production and stock reservation policies that maximize the manufacturer's discounted profit and the average profit per unit time. We show that these policies are threshold‐type policies, and these thresholds are monotone with respect to the primary customer's order size. Using a numerical study we provide insights into how the value of information is affected by the relative demand size of the primary and secondary customers. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
374.
ABSTRACTThis paper examines the importance of closer co-operation in defence-related procurement. Led by the decision that Belgium will lead the procurement of 12 Mine CounterMeasures Vessels (MCMV), the case of a potential Belgian naval construction cluster is discussed. The feasibility of a potential cluster is investigated by looking at key elements of a successful naval construction cluster, the Dutch naval construction cluster, and comparing those key elements to the current Belgian situation. Forming a sustainable Belgian naval construction cluster will be difficult. Most of the procurement process of the MCMVs is set on a European tender. In the long run, due to the absence of both a launching customer and leader firms, no party is able to carry the cluster with investments and knowledge spill-overs. In order to keep public support for large defence-related investments, clustering around the MCMV integration system and proactive cluster support is recommended. 相似文献
375.
ABSTRACTNo issue deserves more scrutiny than the mechanisms whereby popular unrest unleashes civil wars. We argue that one institution – two-tiered security systems – is particularly pernicious in terms of the accompanying civil war risk. These systems’ defining characteristic is the juxtaposition of small communally stacked units that protect regimes from internal adversaries with larger regular armed forces that deter external opponents. These systems aggravate civil war risks because stacked security units lack the size to repress widespread dissent, but inhibit rapid regime change through coup d’état. Regular militaries, meanwhile, fracture when ordered to employ force against populations from which they were recruited. 相似文献