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41.
Cyberspace is an avenue of approach through which a military force can attain objectives of value. Through these cyber avenues of approach, military forces can engage, vet, organize, and direct human agents to accomplish specific activities. Although the objectives of these activities could differ from traditional military objectives, they still have military relevance. This particular manifestation of cyber conflict is neither a new domain of war nor something outside of warfare. Rather, it can be viewed as an emerging avenue of approach in the larger context of military operations, auguring benefits in the integration of cyber activities with operations.  相似文献   
42.
The number of US drone strikes against Al Qaeda in the Arabian Peninsula (AQAP) in Yemen has increased significantly since 2010, but received limited academic attention. This article examines the effectiveness of this drone campaign using an existing theoretical framework. Crucially, we contribute to the framework by adding a fourth intervening variable, namely target correspondence. Through a single case study, it is found that drones have only enjoyed limited success in degrading AQAP's hierarchical structure, qualified human resources and access to key material resources, and in some cases – owing to our target correspondence analysis – this limited success has come at a price. It is found that drones have temporarily disrupted AQAP by successfully eliminating senior leaders involved in coordinating and overseeing external operations. Overall, AQAP's ability to hit Western targets remains significant.  相似文献   
43.
It is well‐known that the efficient set of a multiobjective linear programming (MOLP) problem can be represented as a union of the maximal efficient faces of the feasible region. In this paper, we propose a method for finding all maximal efficient faces for an MOLP. The new method is based on a condition that all efficient vertices (short for the efficient extreme points and rays) for the MOLP have been found and it relies on the adjacency, affine independence and convexity results of efficient sets. The method uses a local top‐down search strategy to determine maximal efficient faces incident to every efficient vertex for finding maximal efficient faces of an MOLP problem. To our knowledge, the proposed method is the first top‐down search method that uses the adjacency property of the efficient set to find all maximal efficient faces. We discuss this and other advantages and disadvantages of the algorithm. We also discuss some computational experience we have had with our computer code for implementing the algorithm. This computational experience involved solving several MOLP problems with the code.  相似文献   
44.
45.
The present article discusses the properties of the mean residual life function in a renewal process. We examine the relationship this function has with the failure rate function and the conventional mean, variance and coefficient of variation of residual life. We also discuss some monotonicity properties of the mean residual life function. A partial order based on the renewal mean residual function is introduced along with its interrelationship with some existing stochastic orders. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
46.
In this article, we study threshold‐based sales‐force incentives and their impact on a dealer's optimal effort. A phenomenon, observed in practice, is that the dealer exerts a large effort toward the end of the incentive period to boost sales and reach the threshold to make additional profits. In the literature, the resulting last‐period sales spike is sometimes called the hockey stick phenomenon (HSP). In this article, we show that the manufacturer's choice of the incentive parameters and the underlying demand uncertainty affect the dealer's optimal effort choice. This results in the sales HSP over multiple time periods even when there is a cost associated with waiting. We then show that, by linking the threshold to a correlated market signal, the HSP can be regulated. We also characterize the variance of the total sales across all the periods and demonstrate conditions under the sales variance can be reduced. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010  相似文献   
47.
We study the supplier relationship choice for a buyer that invests in transferable capacity operated by a supplier. With a long‐term relationship, the buyer commits to source from a supplier over a long period of time. With a short‐term relationship, the buyer leaves open the option of switching to a new supplier in the future. The buyer has incomplete information about a supplies efficiency, and thus uses auctions to select suppliers and determine the contracts. In addition, the buyer faces uncertain demand for the product. A long‐term relationship may be beneficial for the buyer because it motivates more aggressive bidding at the beginning, resulting a lower initial price. A short‐term relationship may be advantageous because it allows switching, with capacity transfer at some cost, to a more efficient supplier in the future. We find that there exists a critical level of the switching cost above which a long‐term relationship is better for the buyer than a short‐term relationship. In addition, this critical switching cost decreases with demand uncertainty, implying a long‐term relationship is more favorable for a buyer facing volatile demand. Finally, we find that in a long‐term relationship, capacity can be either higher or lower than in a short‐term relationship. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009  相似文献   
48.
The client‐contractor bargaining problem addressed here is in the context of a multi‐mode resource constrained project scheduling problem with discounted cash flows, which is formulated as a progress payments model. In this model, the contractor receives payments from the client at predetermined regular time intervals. The last payment is paid at the first predetermined payment point right after project completion. The second payment model considered in this paper is the one with payments at activity completions. The project is represented on an Activity‐on‐Node (AON) project network. Activity durations are assumed to be deterministic. The project duration is bounded from above by a deadline imposed by the client, which constitutes a hard constraint. The bargaining objective is to maximize the bargaining objective function comprised of the objectives of both the client and the contractor. The bargaining objective function is expected to reflect the two‐party nature of the problem environment and seeks a compromise between the client and the contractor. The bargaining power concept is introduced into the problem by the bargaining power weights used in the bargaining objective function. Simulated annealing algorithm and genetic algorithm approaches are proposed as solution procedures. The proposed solution methods are tested with respect to solution quality and solution times. Sensitivity analyses are conducted among different parameters used in the model, namely the profit margin, the discount rate, and the bargaining power weights. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009  相似文献   
49.
The effectiveness of a fire department is largely determined by its ability to respond to incidents in a timely manner. To do so, fire departments typically have fire stations spread evenly across the region, and dispatch the closest truck(s) whenever a new incident occurs. However, large gaps in coverage may arise in the case of a major incident that requires many nearby fire trucks over a long period of time, substantially increasing response times for emergencies that occur subsequently. We propose a heuristic for relocating idle trucks during a major incident in order to retain good coverage. This is done by solving a mathematical program that takes into account the location of the available fire trucks and the historic spatial distribution of incidents. This heuristic allows the user to balance the coverage and the number of truck movements. Using extensive simulation experiments we test the heuristic for the operations of the Fire Department of Amsterdam‐Amstelland, and compare it against three other benchmark strategies in a simulation fitted using 10 years of historical data. We demonstrate substantial improvement over the current relocation policy, and show that not relocating during major incidents may lead to a significant decrease in performance.  相似文献   
50.
This paper explores the notion that US efforts to evade the political costs of war paradoxically contribute to the subsequent exacerbation of costs over time. Leaders seek to purchase political capital in the short term by limiting the costs and requirements of military operations, but in doing so cause strategic and political liabilities to mount in the long run. While identification of such behaviour is not new, insufficient attention has been devoted to explaining its causes, dynamics, and manifestations in relation to key decisions on and in war. Evidence derived from studies of recent American discretionary campaigns is analysed to advance an argument with respect to this pattern of self-defeating strategic behaviour.  相似文献   
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