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161.
In this article, an agent‐based framework to quantify the seismic resilience of an electric power supply system (EPSS) and the community it serves is presented. Within the framework, the loss and restoration of the EPSS power generation and delivery capacity and of the power demand from the served community are used to assess the electric power deficit during the damage absorption and recovery processes. Damage to the components of the EPSS and of the community‐built environment is evaluated using the seismic fragility functions. The restoration of the community electric power demand is evaluated using the seismic recovery functions. However, the postearthquake EPSS recovery process is modeled using an agent‐based model with two agents, the EPSS Operator and the Community Administrator. The resilience of the EPSS–community system is quantified using direct, EPSS‐related, societal, and community‐related indicators. Parametric studies are carried out to quantify the influence of different seismic hazard scenarios, agent characteristics, and power dispatch strategies on the EPSS–community seismic resilience. The use of the agent‐based modeling framework enabled a rational formulation of the postearthquake recovery phase and highlighted the interaction between the EPSS and the community in the recovery process not quantified in resilience models developed to date. Furthermore, it shows that the resilience of different community sectors can be enhanced by different power dispatch strategies. The proposed agent‐based EPSS–community system resilience quantification framework can be used to develop better community and infrastructure system risk governance policies.  相似文献   
162.
O2O外卖作为"互联网+"时代下的新型餐饮模式,日益受到人们的关注。本文研究的O2O外卖服务供应链由一个O2O外卖平台、一个餐饮商家和一个配送骑手构成。O2O外卖平台决策平台的服务质量努力和服务费用,餐饮商家决策产品价格,骑手决策配送服务质量努力程度,同时会受到来自平台或商家的服务质量激励。通过分析商家配送、平台配送和商家自建平台+配送三种运营模式,分别构建O2O外卖服务供应链成员的利润函数,运用博弈理论,优化得到不同模式下O2O外卖服务供应链成员的最优质量控制策略和最优利润。利用公式推导和对比分析,分别探讨了骑手激励金额上限和市场规模对服务供应链最优策略和最优利润的影响。通过数值仿真,可得结论:服务供应链各成员利润均随着市场规模的增大而增大,随着骑手激励金额上限的增加而先增大后减少。当市场规模较小时,平台配送模式下商家最优利润最大。而当市场规模较大时,商家自建平台+配送模式下商家最优利润最大。  相似文献   
163.
Many optimisation problems arise in managing the Blood Donation (BD) supply chain. Most of them have been addressed in the literature, while other problems, e.g. donation scheduling, have not been sufficiently addressed so far. However, blood collection from donors may have a disruptive impact on the entire BD supply chain if not properly managed. For example, scheduling donation appointments based on some system metrics may improve the flow of blood units through the BD supply chain and increase the quality of service perceived by donors. In this short communication, we present the donation scheduling problem and highlight the lack of work in the literature that deals with this problem. Then, we analyse the impact of an unbalanced flow of blood units on the BD system and the benefits that may derive from a suitable appointment scheduling. Finally, we propose suggestions for future research in BD collection scheduling that may improve the BD process.  相似文献   
164.
生鲜供应链整体生鲜度的提升对减少浪费、提高供应链整体盈利水平及社会福利有重要意义。本文基于消费者效用理论研究了两供应商和单一零售商组成的供应链系统,构建了单周期下生鲜农产品生鲜度激励模型,模型以供应商为领导者,采用Stackelberg博弈方法求解得到了均衡状态下供应商、零售商的最优定价策略及供应商新鲜度努力选择。研究结果表明,供应商和零售商利润与消费者价格敏感系数呈反向变化,与新鲜度敏感系数呈同向变化。在价格竞争市场,供应商保鲜努力程度和利润与价格替代率呈反向变化;在生鲜度竞争市场,供应商保鲜努力程度和利润与新鲜度替代率呈同向变化。基于研究结论,厂商及政府应当联手引导消费者的消费观念,尽可能减少由于信息不对称引致的道德风险,在市场价格替代率不变甚至降低的情形下,提高生鲜度替代率,使得消费者的意愿支付价格上升,提高自身讨价还价能力,获取更多利润。  相似文献   
165.
李鑫  于辉 《中国管理科学》2019,27(12):43-54
产品与服务融合缓解了"供需错位"矛盾,使得产品服务供应链探索成为"供给侧结构性改革"下供需结构性匹配的重要路径。本文刻画产品服务视角下供应链组织结构的本质特征,构建产品服务供应链合作模型,探讨合作机制下"帕累托改进"区间存在性,揭示合作机制对产品服务供应链效率的作用机理。核心研究发现:供应链多元化组织结构加剧收益分配冲突,并导致服务规模与供应链效率"倒挂"现象,而合作机制下"双重收益共享"合作模型能提升产品服务供应链效率。  相似文献   
166.
Public support for nuclear power generation has decreased in Japan since the Fukushima Daiichi nuclear accident in March 2011. This study examines how the factors influencing public acceptance of nuclear power changed after this event. The influence factors examined are perceived benefit, perceived risk, trust in the managing bodies, and pro‐environmental orientation (i.e., new ecological paradigm). This study is based on cross‐sectional data collected from two online nationwide surveys: one conducted in November 2009, before the nuclear accident, and the other in October 2011, after the accident. This study's target respondents were residents of Aomori, Miyagi, and Fukushima prefectures in the Tohoku region of Japan, as these areas were the epicenters of the Great East Japan Earthquake and the locations of nuclear power stations. After the accident, trust in the managing bodies was found to have a stronger influence on perceived risk, and pro‐environmental orientation was found to have a stronger influence on trust in the managing bodies; however, perceived benefit had a weaker positive influence on public acceptance. We also discuss the theoretical and practical implications of these findings.  相似文献   
167.
Information before unblinding regarding the success of confirmatory clinical trials is highly uncertain. Current techniques using point estimates of auxiliary parameters for estimating expected blinded sample size: (i) fail to describe the range of likely sample sizes obtained after the anticipated data are observed, and (ii) fail to adjust to the changing patient population. Sequential MCMC-based algorithms are implemented for purposes of sample size adjustments. The uncertainty arising from clinical trials is characterized by filtering later auxiliary parameters through their earlier counterparts and employing posterior distributions to estimate sample size and power. The use of approximate expected power estimates to determine the required additional sample size are closely related to techniques employing Simple Adjustments or the EM algorithm. By contrast with these, our proposed methodology provides intervals for the expected sample size using the posterior distribution of auxiliary parameters. Future decisions about additional subjects are better informed due to our ability to account for subject response heterogeneity over time. We apply the proposed methodologies to a depression trial. Our proposed blinded procedures should be considered for most studies due to ease of implementation.  相似文献   
168.
This study examined how Turkey uses social media as a tool for public diplomacy and how the state’s soft-power efforts have recently changed on the global stage. The researchers constructed a dataset of 2769 Twitter posts by the Turkish government’s most influential public diplomacy accounts. The analyses revealed that the focus of Turkey’s Twitter public diplomacy has become concentrated on the Middle East and North Africa (MENA) region and is thematically focused on the political values embodied by the Turkish president. The findings suggest that public diplomacy remains to be the diplomacy of the government, not of the public, and social media is used as just another tool for propaganda, not as a means of engagement with foreign publics. Further, the findings indicate the emergence of a “new” cult of personality in public diplomacy and point out the instrumental role of social media in changing the dynamics of leader-follower relationship. The study contributes to public relations theory and practice by advancing the burgeoning public diplomacy scholarship at the intersection of social media and relational approaches.  相似文献   
169.
Pimps, or male managers of female sex workers, are commonly represented in popular culture as hypermasculine and as a ubiquitous part of sex work. However, there is little empirical scholarship on pimps or the construction of their masculinity. Drawing on ethnographic and interview data, this article demonstrates how pimps produce a “revanchist masculinity” that seeks to reclaim power from women and establish status over other men. Pimps are suspicious of sex workers’ motives and deny them decision‐making power and profit sharing—processes that highlight how work practices can structure gender identity construction.  相似文献   
170.
20世纪70年代的国际石油危机有着深厚的历史根源,它源于国际石油权力结构的急剧变革。60年代后期开始,随着国际石油市场日趋紧张,产油国的地位日益改善,它们从石油公司获得越来越多的石油权力,其中国际石油公司与产油国签订的"德黑兰协定"和"的黎波里协定"发挥了至关重要的作用,是产油国能够针对西方国家使用减产、禁运和提价等石油武器的前提条件。  相似文献   
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