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271.
Despite the large number and variety of studies addressing the relationship between military spending and economic growth, a consensus regarding the exact nature of any relationship between the two has proven elusive. This study uses a panel co-integration approach to examine the relationship between military spending and economic growth in the five South Asian countries of India, Pakistan, Nepal, Sri Lanka and Bangladesh over the period of 1988–2007. It finds that a 1% increase in military spending increases real GDP by only 0.04%, suggesting that the substantial amount of public expenditure that is currently directed towards military purposes in these countries has a negligible impact upon economic growth.  相似文献   
272.
An alternating renewal process starts at time zero and visits states 1,2,…,r, 1,2, …,r 1,2, …,r, … in sucession. The time spent in state i during any cycle has cumulative distribution function Fi, and the sojourn times in each state are mutually independent, positive and nondegenerate random variables. In the fixed time interval [0,T], let Ui(T) denote the total amount of time spent in state i. In this note, a central limit theorem is proved for the random vector (Ui(T), 1 ≤ ir) (properly normed and centered) as T → ∞.  相似文献   
273.
This paper extends the Low-Lippman M/M/1 model to the case of Gamma service times. Specifically, we have a queue in which arrivals are Poisson, service time is Gamma-distributed, and the arrival rate to the system is subject to setting an admission fee p. The arrival rate λ(p) is non-increasing in p. We prove that the optimal admission fee p* is a non-decreasing function of the customer work load on the server. The proof is for an infinite capacity queue and holds for the infinite horizon continuous time Markov decision process. In the special case of exponential service time, we extend the Low-Lippman model to include a state-dependent service rate and service cost structure (for finite or infinite time horizon and queue capacity). Relatively recent dynamic programming techniques are employed throughout the paper. Due to the large class of functions represented by the Gamma family, the extension is of interest and utility.  相似文献   
274.
In this paper we consider n jobs and a number of machines in parallel. The machines are identical and subject to breakdown and repair. The number may therefore vary over time and is at time t equal to m(t). Preemptions are allowed. We consider three objectives, namely, the total completion time, ∑ Cj, the makespan Cmax, and the maximum lateness Lmax. We study the conditions on m(t) under which various rules minimize the objective functions under consideration. We analyze cases when the jobs have deadlines to meet and when the jobs are subject to precedence constraints. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004.  相似文献   
275.
This article examines a problem faced by a firm procuring a material input or good from a set of suppliers. The cost to procure the material from any given supplier is concave in the amount ordered from the supplier, up to a supplier‐specific capacity limit. This NP‐hard problem is further complicated by the observation that capacities are often uncertain in practice, due for instance to production shortages at the suppliers, or competition from other firms. We accommodate this uncertainty in a worst‐case (robust) fashion by modeling an adversarial entity (which we call the “follower”) with a limited procurement budget. The follower reduces supplier capacity to maximize the minimum cost required for our firm to procure its required goods. To guard against uncertainty, the firm can “protect” any supplier at a cost (e.g., by signing a contract with the supplier that guarantees supply availability, or investing in machine upgrades that guarantee the supplier's ability to produce goods at a desired level), ensuring that the anticipated capacity of that supplier will indeed be available. The problem we consider is thus a three‐stage game in which the firm first chooses which suppliers' capacities to protect, the follower acts next to reduce capacity from unprotected suppliers, and the firm then satisfies its demand using the remaining capacity. We formulate a three‐stage mixed‐integer program that is well‐suited to decomposition techniques and develop an effective cutting‐plane algorithm for its solution. The corresponding algorithmic approach solves a sequence of scaled and relaxed problem instances, which enables solving problems having much larger data values when compared to standard techniques. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
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There is often a call in any organization to make the system ‘more efficient’. This document describes a novel framework for measuring organizational efficiency at the microeconomic level. We show how this framework can be used to monitor an organization using data typically available in extant performance management frameworks. This is most useful in large organizations with eclectic outputs where resources may be too constrained to perform industry-level analyses, such as data envelope analysis, to infer efficiency. This method helps illuminate how the factors of an organization’s internal practices can affect its efficient use of resources.  相似文献   
279.
Recently, Finland and Sweden decided to substantially deepen their defence cooperation and this project involves creating a bilateral standing Naval Task Group (SFNTG). The present article aims at examining the deepening naval cooperation between Finland and Sweden from a regional integration perspective, focusing on its motives, current challenges and future prospects. Driven by perceptions of common challenges and desires for cost-effectiveness, and strengthened by recent successes on sea surveillance and a combined Amphibious Task Unit, the bilateral project has considerable potential to achieve success. To fulfil its objectives, substantial legal changes in both countries are required to allow the use of force on each other’s territorial waters. To cater for the requirement of not conflicting with EU, NORDEFCO or NATO cooperations, the bilateral Task Group must operate according to NATO standards and by using English as the language in command and control. The costs of adjusting the naval units to NATO’s technical requirements are far from negligible and this issue still remains to be solved. If Finland and Sweden manage to incorporate new policies, common structures and common organisational norms among their navies, an even deeper integration, as in Belgium and the Netherlands, are conceivable.  相似文献   
280.
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