The Imperfect Peace: Explaining Paramilitary Violence in Northern Ireland

This article examines why paramilitary campaigns in Northern Ireland have continued despite the current peace process. In advancing three instrumental explanations of paramilitary violence, the author provides a useful analytical framework which shows that while organizational interpretations are dominating the public discourse, republicans and loyalists continue to use paramilitary violence as a strategic means of threat and coercion. Furthermore, even though policy implications are not discussed in detail, it will be demonstrated that the dominance of organizational imperatives has resulted in excessive leniency by the state, which - in turn - has contributed to the fragility of the peace process.     

Locational tying of complementary retail items

We study a selling practice that we refer to as locational tying (LT), which seems to be gaining wide popularity among retailers. Under this strategy, a retailer “locationally ties” two complementary items that we denote by “primary” and “secondary.” The retailer sells the primary item in an appropriate “department” of his or her store. To stimulate demand, the secondary item is offered in the primary item's department, where it is displayed in very close proximity to the primary item. We consider two variations of LT: In the multilocation tying strategy (LT‐M), the secondary item is offered in its appropriate department in addition to the primary item's department, whereas in the single‐location tying strategy (LT‐S), it is offered only in the primary item's location. We compare these LT strategies to the traditional independent components (IC) strategy, in which the two items are sold independently (each in its own department), but the pricing/inventory decisions can be centralized (IC‐C) or decentralized (IC‐D). Assuming ample inventory, we compare and provide a ranking of the optimal prices of the four strategies. The main insight from this comparison is that relative to IC‐D, LT decreases the price of the primary item and adjusts the price of the secondary item up or down depending on its popularity in the primary item's department. We also perform a comparative statics analysis on the effect of demand and cost parameters on the optimal prices of various strategies, and identify the conditions that favor one strategy over others in terms of profitability. Then we study inventory decisions in LT under exogenous pricing by developing a model that accounts for the effect of the primary item's stock‐outs on the secondary item's demand. We find that, relative to IC‐D, LT increases the inventory level of the primary item. We also link the profitability of different strategies to the trade‐off between the increase in demand volume of the secondary item as a result of LT and the potential increase in inventory costs due to decentralizing the inventory of the secondary item. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009     

开放架构的数字视频管理系统iView研究与实现

iView是我们研制的基于多模态元数据提取,具有开放架构且支持无线移动存取的数字视频全内容管理系统。本文讨论了系统的需求,体系框架设计实现,描述了其中涉及的关键技术思想,并对存在的问题和研究方向做了简单探讨。     

Rent seeking and defence expenditure

A plethora of arguments from the ‘public choice school’ suggest that public goods are ‘under‐supplied’ by comparison with public sector provision of more private goods. The implication is that rent seeking by the ‘military‐industrial complex’ serves, in some measure, to offset potential allocative inefficiency. In this paper a comparison of rent seeking by producers of public goods and producers of private goods identifies a bias that favours public good supply. The bias results from the different way in which collective demand for public goods and for private goods is expressed. The prospect of larger rents to the ‘military‐industrial complex’ implies greater rent‐seeking expenditures in this sector. The extent to which public goods (and, in particular, defence) are ‘under supplied’ is much exaggerated.     

Scheduling data transmission under an {si; o} policy

This paper discusses scheduling of data transmission when data can only be transmitted in one direction at a time. A common policy used is the so-called alternating priority policy. In this paper we select a more general class of policies named the {S_i; O} policy. We show how to determine the optimal parameters of the {S_i; O} policy for given system parameters. We also give a simple example to show that {S_i; O} policy is, in fact, better then alternating priority policy.     

Optimal layered search

This article investigates the problem of planning an optimal layered search for a stationary target. A search is layered if it assigns each point in the search space an integer number of glimpses or looks. General necessary and sufficient conditions and an existence theorem are obtained. The special case in which the initial target distribution is bivariate normal is considered in detail.