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41.
Extended warranties provide “piece of mind” to a consumer in that product failures which occur after the base warranty expires are rectified at little or no cost. They also provide an additional source of revenue for manufacturers or third‐party providers, such as retailers or insurance providers, and help cultivate consumer loyalty. In this article, we analyze a number of extended warranty contracts which differ in design, including restrictions on deferrals and renewals. With the use of dynamic programming, we compute the optimal strategy for a consumer with perfect information and determine the optimal pricing policy for the provider given the consumer's risk characterization. We also provide insight into when different contracts should be issued. Finally, we illustrate how profits can be dramatically increased by offering menus of warranty contracts, as opposed to stand alone contracts, with the use of integer programming. Surprisingly, risk‐taking consumers provide the greatest benefit to offering menus. These insights can help a company develop a comprehensive warranty planning strategy for given products or product lines. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009 相似文献
42.
William C. Spracher 《Low Intensity Conflict & Law Enforcement》2002,11(1):29-54
The newest US Cabinet department is Homeland Security (DHS). One of the most controversial aspects in the process of developing this entity is the role of intelligence in providing information on the increasing terrorist threat. This article examines the intelligence challenges for homeland security. In doing so, it explores the problems of merging disparate cultures - law enforcement vs intelligence, civil entities vs military, federal vs state and local jurisdictions, and domestic focus vs international perspective. Given the nature of the globalized, asymmetric threat, the need for more and better intelligence sharing is obvious. Terrorists and other criminals do not respect international boundaries; in fact, they exploit them in an effort to prevent effective and timely countermeasures. This demands that robust multinational collaboration and interagency coordination be practiced. 相似文献
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A system of two parallel queues where the arrivals from a single stream of customers join the shorter queue is considered. Arrivals form a homogeneous Poisson stream and the service times in each of the two queues are independent exponential variates. By treating one of the queues as bounded, the steady-state probability vector for the system can be expressed in a modified matrix-geometric form and can be computed efficiently. Computational procedures for the sojourn time distribution and characteristics of the departure stream are developed. Some numerical results are presented, and based on these results an efficient approximation scheme for the model is developed which can be readily extended to systems with more than two parallel queues. 相似文献
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Orienteering is a sport in which start and end points are specified along with other locations. These other locations have associated scores. Competitors seek to visit, in a fixed amount of time, a subset of these locations on the way from the start point to the end point in order to maximize the total score. An effective center-of-gravity heuristic is presented that outperforms heuristics from the literature. 相似文献
47.
Adam D. Bramoweth James Luther Barbara H. Hanusa Jon D. Walker Charles W. Atwood Jr. Anne Germain 《Defence and Peace Economics》2018,29(1):78-90
AbstractInsomnia is prevalent among Veterans with post-traumatic stress disorder (PTSD), it exacerbates PTSD symptoms, and it contributes to impaired functioning and quality of life. To improve treatment outcomes, it is important to identify risk factors for insomnia and sedative-hypnotic use. Classification and regression trees and logistic regression models were used to identify variables associated with insomnia or sedative-hypnotic use. Key findings include low insomnia diagnosis rates (3.5–5.6%) and high rates of sedative-hypnotics (44.2–49.0%). Younger Veterans and those without a breathing-related sleep disorder (BRSD) were more likely to receive an insomnia diagnosis. Veterans with greater service connection and those with an alcohol/substance use disorder were more likely to be prescribed sedative-hypnotics. Interaction terms may have identified potential groups at risk of being under-diagnosed with insomnia (i.e. non-black Veterans with psychiatric co-morbidity, black Veterans without psychiatric co-morbidity) as well as groups at risk for sedative-hypnotic use (i.e. younger Veterans without BRSD). In sum, Veterans with PTSD have high rates of sedative-hypnotic use despite minimal evidence they are effective. This is counter to recommendations indicating behavioral interventions are the first-line treatment. Policy changes are needed to reduce use of sedative-hypnotics and increase access to behavioral insomnia interventions. 相似文献
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Lawrence E. Cline 《Defense & Security Analysis》2016,32(4):293-311
Particularly in African operations, United Nations (UN) peacekeeping forces have faced significant problems in restoring stability. In at least a few situations, unilateral national military interventions have been launched in the same countries. In the cases of Sierra Leone and Côte d’Ivoire, the British and French interventions respectively played a significant role in re-establishing stability. Lessons from these operations suggest that if effective coordination and liaison channels are established, such hybrid unilateral-UN missions can in fact be more successful than “pure” peace operations. 相似文献
50.
Timothy Edmunds Antonia Dawes Paul Higate K. Neil Jenkings Rachel Woodward 《Defence Studies》2016,16(2):118-136
In recent years, there has been a sharp growth in political and sociological interest in the British military. Set against the backdrop of the armed forces’ increasing presence in everyday life, alongside the organizations’ ongoing restructuring, the current paper focuses on the MoD’s problematic attempts to recruit 30,000 reservists by 2020; what has become known as the Future Reserves 2020 programme (FR2020). We argue that these changes are driven in part by the need to cut costs in defence. However, we also suggest that they are a reflection of the changing nature of modern military organisation, and the manner in which armed forces engage with the societies of which they are a part, and with the citizens that make up that society. We locate FR2020 programme in the context of a wider narrative about the changing nature of military organisation in contemporary western democracies, identifying structural, circumstantial and normative reasons for change. We also examine the specific challenges of implementing FR2020 in practice, including issues of recruitment and retention, integration and support, and relations with families and employers, drawing on the experience of comparator countries to do so. We conclude by considering the implications of these changes, both for the future of UK armed forces, and for the evolving nature of military-society relations in Britain. 相似文献