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281.
Emerging sharing modes, like the consumer-to-consumer (C2C) sharing of Uber and the business-to-consumer (B2C) sharing of GoFun, have considerably affected the retailing markets of traditional manufacturers, who are motivated to consider product sharing when making pricing and capacity decisions, particularly electric car manufacturers with limited capacity. In this paper, we examine the equilibrium pricing for a capacity-constrained manufacturer under various sharing modes and further analyze the impact of capacity constraint on the manufacturer's sharing mode selection as well as equilibrium outcomes. We find that manufacturers with low-cost products prefer B2C sharing while those with high-cost products prefer C2C sharing except when the sharing price is moderate. However, limited capacity motivates manufacturers to enter into the B2C sharing under a relatively low sharing price, and raise the total usage level by sharing high-cost products. We also show that the equilibrium capacity allocated to the sharing market with low-cost products first increases and then decreases. Finally, we find that sharing low-cost products with a high limited capacity leads to a lower retail price under B2C sharing, which creates a win-win situation for both the manufacturer and consumers. However, sharing high-cost products with a low limited capacity creates a win-lose situation for them.  相似文献   
282.
Ride-hailing platforms such as Uber, Lyft, and DiDi have achieved explosive growth and reshaped urban transportation. The theory and technologies behind these platforms have become one of the most active research topics in the fields of economics, operations research, computer science, and transportation engineering. In particular, advanced matching and dynamic pricing (DP) algorithms—the two key levers in ride-hailing—have received tremendous attention from the research community and are continuously being designed and implemented at industrial scales by ride-hailing platforms. We provide a review of matching and DP techniques in ride-hailing, and show that they are critical for providing an experience with low waiting time for both riders and drivers. Then we link the two levers together by studying a pool-matching mechanism called dynamic waiting (DW) that varies rider waiting and walking before dispatch, which is inspired by a recent carpooling product Express Pool from Uber. We show using data from Uber that by jointly optimizing DP and DW, price variability can be mitigated, while increasing capacity utilization, trip throughput, and welfare. We also highlight several key practical challenges and directions of future research from a practitioner's perspective.  相似文献   
283.
Foreign policy program transfer, the shifting of implementation responsibility for a foreign policy program from one organization to another, is a ubiquitous, yet under-studied, counterinsurgency phenomenon. This article conceptually develops program transfer as an important object of study; analyzes, using archival sources, an empirical case of program transfer, Operation Switchback, drawn from US counterinsurgency practice in South Vietnam; and formulates two preliminary theoretical claims related to program transfer: (1) transferred programs will tend to be altered in accordance with the characteristics of the gaining organization, and (2) program transfer may act as a signal or early-warning indicator of foreign policy change.  相似文献   
284.
备件需求量预测在装备保障工作中发挥着重要作用。预防性维修可以消除装备潜在的故障或避免装备发生故障后所导致的严重后果,从而使装备始终处于期望状态。预防性维修策略下备件需求量建模能够以可预见的可靠性数据为基础进行,其关键问题是最佳更换间隔时间的确定。针对威布尔分布装备备件,采用年龄更换策略,确定最佳更换间隔时间,并在此基础上导出威布尔型备件需求计算模型,为备件需求量的预测提供了一种简单有效的方法。  相似文献   
285.
在基于正交频分复用技术的放大转发协作通信系统中,针对传统信道估计算法估计精度差的问题,提出一种基于判别分析阈值滤波离散傅立叶变换信道估计算法。该算法首先通过设置改进的阈值门限初步获得信道有效抽头,然后利用马氏距离判别分析对已检测出的信道抽头修正。仿真结果表明:和传统方法相比,提出方法有效地滤除了信道估计中的噪声,改善了信道估计精度和误码率性能。  相似文献   
286.
美军在军事人才培养的体系构筑、目标设定、课目设置等方面有着众多独到之处。《军官职业军事教育政策》是美军规范军官职业军事教育的指导性文件,研究掌握其核心内容的发展演变,从中提取美军职业教育改革的先进理念和成熟做法,可为我军军事职业教育建设提供经验借鉴。  相似文献   
287.
Mark Erbel 《Defence Studies》2017,17(2):135-155
This article reappraises the two most-studied country cases of military outsourcing: the USA and the UK. It argues that the contemporary wave of military contracting stretches back to the beginning of the cold war and not only to the demobilisation of armies in the 1990s or the neoliberal reforms introduced since the 1980s. It traces the political, technological and ideational developments that laid the groundwork for these reforms and practices since the early cold war and account for its endurance today. Importantly, it argues that a persistent gap between strategic objectives and resources, i.e. the challenge to reconcile ends and means, is an underlying driver of military contracting in both countries. Contemporary contracting is thus most closely tied to military support functions in support of wider foreign and defence political objectives. Security services in either state may not have been outsourced so swiftly, if at all, without decades of experience in outsourcing military logistics functions and the resultant vehicles, processes and familiarities with public-private partnerships. The article thus provides a wider and deeper understanding of the drivers of contractualisation, thereby improving our understanding of both its historical trajectory and the determinants of its present and potential futures.  相似文献   
288.
孙平 《国防科技》2017,38(6):028-035
许多国家和国际性科学组织在科研诚信建设方面都开展了大量工作。目前,国内对于国外这方面的做法和经验,特别是近年来的最新实践只有零星的报道。文章比较全面地介绍国外科研诚信建设的主要发展动向和各国面临的一些共同挑战,进而分析提出其对我国科研诚信建设策略的启示,并就今后应加强的若干方面工作提出建议。  相似文献   
289.
This study provides an explanation of terrorism by examining interactions between the terrorist group with a minority as a potential pool of recruits and the government supported by a majority. A hawkish deterrence policy makes it more risky for terrorists to launch attacks, but heightens the anti‐government feeling of the terrorist group. In addition, the payoff for the government depends not only on the payoff loss associated with the level of terrorism, but also on the political payoff from the action itself of adopting a hawk policy due to its politicians’ vested interests. We first show that whether the deterrence policy should be ‘hawk to ‘dove is closely dependent on the relationships among the risk associated with terrorism, the anti‐government feeling of the terrorist group, and the political payoff for the government. This study then introduces transnational support enhancing the capability of a terrorist group to intensify its activity and shows that the emergence of transnational support may cause the government to reform its deterrence policy from ‘dove’ toward ‘hawk,’ with terrorism intensified in the society.  相似文献   
290.
Defense budgets in Japan have been complicated compromises from numerous inputs ‐ including threat perceptions, domestic industrial/technological base development, support for the bilateral security treaty with the United States and internal bureaucratic politics ‐ but with the fall of the former Soviet Union, the clearest justification for higher spending disappeared. Double‐digit defense spending increases that were common in the 1980s have been replaced by annual increases lower than present inflation rates, resulting in negative real growth in the country's defense budget. Domestic economic problems and consistent government pressures for smaller budgets have further slowed annual growth in total spending and have contributed to lower procurement budgets. As a result, the domestic Japanese defense industry is facing far more constrained conditions from the growth years of a decade before.

Government policymakers are examining Japan's regional security environment as well as its alliance with the United States to determine the appropriate course for the country to take in the coming years. The formal security treaty with the United States is likely to remain a major element of government positions, but other aspects of the country's overall security posture are open to debate. Perceptions of a reduced threat environment are fueling additional pressures for defense budget cuts.

The domestic defense industry seeks means to assure its survival in domestic defense markets in this constrained environment. Expansion into overseas markets to offset declining domestic markets is an option that currently is constrained by policy restrictions on arms exports. Industry is advocating re‐examination of those policies and unlike earlier years, government appears willing to respond positively but cautiously to this lobbying.  相似文献   
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