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231.
We consider price and capacity decisions for a profit‐maximizing service provider in a single server queueing system, in which customers are boundedly rational and decide whether to join the service according to a multinomial logit model. We find two potential price‐capacity pair solutions for the first‐order condition of the profit‐maximizing problem. Profit is maximized at the solution with a larger capacity, but minimized at the smaller one. We then consider a dynamically adjusting capacity system to mimic a real‐life situation and find that the maximum can be reached only when the initial service rate is larger than a certain threshold; otherwise, the system capacity and demand shrink to zero. We also find that a higher level of customers’ bounded rationality does not necessarily benefit a firm, nor does it necessarily allow service to be sustained. We extend our analysis to a setting in which customers’ bounded rationality level is related to historical demand and find that such a setting makes service easier to sustain. Finally we find that bounded rationality always harms social welfare. 相似文献
232.
灰色-马尔科夫模型在机场道面使用性能预测中的应用 总被引:1,自引:0,他引:1
介绍利用灰色-马尔科夫模型对机场道面使用性能进行预测的基本方法和具体步骤,并给出了工程实例.应用分析表明,该方法能够充分利用机场道面使用中各段历史数据,较好地对机场道面使用性能进行预测,且预测结果比单纯的灰色模型有更高的精度. 相似文献
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This article develops a mathematical model and heuristic algorithm to design recreational boating mooring fields. The boating industry is important to the Florida economy, and boat storage is becoming a concern among those in the industry. The mooring field design problem is formulated to maximize the total number of boat feet moored in the mooring field. In the model, we allow two adjacent moorings to overlap, which introduces a risk that under certain conditions the boats on these moorings could contact each other. We identify the conditions when contact is possible and quantify the probability of contact. The mooring field design problem is formulated as a nonlinear mixed‐integer programming problem. To solve the problem, we decompose it into two separate models, a mooring radii assignment model and a mooring layout model, which are solved sequentially. The first is solved via exhaustive enumeration and the second via a depth‐first search algorithm. Two actual mooring fields are evaluated, and in both cases our model leads to better layouts than ones experts developed manually. The mooring field design model rationalizes the mooring field design and shows that in one case by increasing the risk from 0 to 1%, the mooring efficiency increases from 74.8% to 96.2%. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009 相似文献
235.
炮管内膛烧蚀磨损现象的分析 总被引:1,自引:0,他引:1
目前国内外对火炮身管寿命的研究表明,火炮身管疲劳寿命低的问题已基本解决,而烧蚀磨损寿命已成为影响其寿命的主要因素。就此介绍了身管烧蚀磨损的特征和危害,并且分析了造成这些特征和危害的原因,最后就解决这些问题提出了相应的措施。 相似文献
236.
为提高新一代北斗无线电测定卫星服务在有限带宽内的信息服务容量,借鉴了正交频分复用的理念,新体制无线电测定卫星服务信号设计采用多个子载波进行信号调制。以往针对多用户的分析主要考虑多址干扰,对载波频偏损耗和伪码损耗单独考虑,这不能解释新体制调制在相同的同步头的情况下其他子载波上信号在当前观测子载波上形成较大相关峰的问题,该问题对信号接收产生较大干扰。本文对该问题产生机理进行了分析,并提出了两种相关干扰的消除方法。 相似文献
237.
Jomana Amara 《Defense & Security Analysis》2019,35(3):326-342
In 1968, President Nixon established the Commission on an All-Volunteer Armed Force, or the Gates Commission, which served as the impetus and justification for an All-Volunteer Force (AVF). At the end of its deliberations, the commission recommended abolishing the draft and transforming the U.S. military into a force of volunteers beginning in 1973. Interestingly, the debate regarding the merits of both systems appeared to be largely economic – with cost–benefit analysis playing the primary role. Lately, we are beginning to see a new, politically-motivated impetus for returning to a “system of national service.” The ideas spurring this debate are many: the need to reaffirm the nation state, the commitment of citizens to the state, political ownership and oversight of the forces, the need for social equity in serving the nation, limiting the support for armed conflict by burden-sharing among citizens, and equitably spreading the personal cost of war. 相似文献
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This paper considers optimal staffing in service centers. We construct models for profit and cost centers using dynamic rate queues. To allow for practical optimal controls, we approximate the queueing process using a Gaussian random variable with equal mean and variance. We then appeal to the Pontryagin's maximum principle to derive a closed form square root staffing (SRS) rule for optimal staffing. Unlike most traditional SRS formulas, the main parameter in our formula is not the probability of delay but rather a cost‐to‐benefit ratio that depends on the shadow price. We show that the delay experienced by customers can be interpreted in terms of this ratio. Throughout the article, we provide theoretical support of our analysis and conduct extensive numerical experiments to reinforce our findings. To this end, various scenarios are considered to evaluate the change in the staffing levels as the cost‐to‐benefit ratio changes. We also assess the change in the service grade and the effects of a service‐level agreement constraint. Our analysis indicates that the variation in the ratio of customer abandonment over service rate particularly influences staffing levels and can lead to drastically different policies between profit and cost service centers. Our main contribution is the introduction of new analysis and managerial insights into the nonstationary optimal staffing of service centers, especially when the objective is to maximize profitability. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 615–630, 2017 相似文献
240.
随着网络中可供选择QoS服务日益增多,在用户请求服务时,为了确保用户获得满足其功能与QoS要求的服务,提出了一种基于灰关联分析的QoS服务选择方法,根据用户对网络服务的QoS需求估计各项QoS指标的主观权重,以用户的偏好感知作为服务选择的约束条件;基于候选服务集合构建候选服务决策矩阵,采用灰关联分析方法从中获得用户QoS满意度最高的服务。仿真和分析表明,该服务选择策略能为服务质量敏感的用户提供有效的满足QoS需求的服务方案。 相似文献