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161.
在零售商存在资金不足和顾客需求随机情况下,以报童模型为基础,针对变质品构建了供应链金融问题和ACC支付模式(提前支付Advance、现金支付Cash和信用支付Credit)相结合的零售商订货模型,即零售商与供应商、融资机构合作条件下的模型。研究表明,零售商会随着最优订货批量和最低期望成本的增加和降低趋势,进而调整订货量,从而规避供大于求的风险,最终降低总的期望成本。同时供应商可以适当调整支付比例,让零售商来分担坏账和商品变质风险。  相似文献   
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163.
In the nuclear power industry, Level 3 probabilistic risk assessment (PRA) is used to estimate damage to public health and the environment if a severe accident leads to large radiological release. Current Level 3 PRA does not have an explicit inclusion of social factors and, therefore, it is not possible to perform importance ranking of social factors for risk‐informing emergency preparedness, planning, and response (EPPR). This article offers a methodology for adapting the concept of social vulnerability, commonly used in natural hazard research, in the context of a severe nuclear power plant accident. The methodology has four steps: (1) calculating a hazard‐independent social vulnerability index for the local population; (2) developing a location‐specific representation of the maximum radiological hazard estimated from current Level 3 PRA, in a geographic information system (GIS) environment; (3) developing a GIS‐based socio‐technical risk map by combining the social vulnerability index and the location‐specific radiological hazard; and (4) conducting a risk importance measure analysis to rank the criticality of social factors based on their contribution to the socio‐technical risk. The methodology is applied using results from the 2012 Surry Power Station state‐of‐the‐art reactor consequence analysis. A radiological hazard model is generated from MELCOR accident consequence code system, translated into a GIS environment, and combined with the Center for Disease Control social vulnerability index (SVI). This research creates an opportunity to explicitly consider and rank the criticality of location‐specific SVI themes based on their influence on risk, providing input for EPPR.  相似文献   
164.
为了研究法兰盘阶梯轴零件成形过程,确定其合理的工艺方案,课题组运用Deform 3D软件对带法兰盘阶梯轴零件镦挤过程进行数值模拟。通过模拟结果对初定工艺方案进行分析,确定了3步成形工艺,并对该工艺进行改进。基于正交试验对改进工艺进行优化,综合模具载荷、折叠角大小和分布及应力分布等因素,确定了最佳的工艺方案。结果表明:采用3步成形工艺时,对法兰盘进行2步镦粗成形,即采用挤压法兰盘1次镦粗 法兰盘2次镦粗成形工艺,该工艺可有效降低模具载荷、折叠角的角度和面积及零件应力;且当压力机工作速度为5 mm/s,法兰盘拐角处模具圆角半径为5 mm,摩擦因数为0.05时,工件成形质量较优。通过实际生产获得了表面质量良好的法兰盘阶梯轴零件。  相似文献   
165.
广州驻防八旗生计问题探析   总被引:1,自引:0,他引:1  
摘要:满清定都北京以后,八旗军民合一的体制被打破,清政府为维护政权的稳固,分派八旗军在全国多处驻防。广州八旗在 驻防初期,有钱粮制度作保障,且旗民人口较少,因此,旗民生活较为宽裕,但随着清政府财政的枯竭,广州八旗旗民人口的增 长,广州驻防八旗旗民面临着严峻的生计问题,虽然广州采取了四项主要措施来解决旗民的生计问题,但这些措施对于多数生 计维艰的八旗旗民来说,仍是杯水车薪,最终广州八旗旗民突破了八旗驻防制度的种种束缚,开始自谋生路  相似文献   
166.
In this paper, building upon the idea of cross-sectional survival probabilities developed by Brouard (Espaces Popul Soc 2(14–15):157–168, 1986), we propose using stochastic models to study the evolution of a new type of survival curves called hybrid survival curve. We find that the three-factor survival model provides a better model fitting than the two-factor survival model. Furthermore, the three time-varying parameters are highly interpretable and their respective trends can be used as an indicator for the rectangularisation of survival curve. On top of that, we demonstrate how the time-varying parameters can be extrapolated into the future to obtain projected hybrid survival curves.  相似文献   
167.
通过理论分析和实验验证,证明了采用同态滤波的方法识别机器扭矩载荷的可行性。同时提出了根据时序模型的Green函数来判定窗函数宽度的方法,减少了选取窗函数宽度的盲目性。作为应用实例,给出了采煤机扭矩的识别结果。  相似文献   
168.
This paper examines generational politics in the Korean American community in Los Angeles. After outlining how the Immigration Act of 1965 led to the acceleration of generational transition in the contemporary immigrant experience, the paper focuses its attention on the entry of the post-immigrant generation into Korean American community politics. Relying on interviews and case studies, the entry of the post-immigrant generation is examined both as a source of new political resources for community mobilization as well as a new source of intra-community conflict. As greater numbers of the post-immigrant generation reach adulthood and become active in political affairs, the issue of generational politics will play an increasingly important role for shaping not only the political developments in immigrant communities but also the broader politics of the American society.  相似文献   
169.
A formal definition of cultural industries is developed following four distinct features of cultural goods: (a) oversupply, (b) quality uncertainty, (c) network effects and (d) demand reversal. Drawing on economic and socio-psychological notions of ‘network’, increasing returns and social contagion effects are distinguished. Increasing returns may govern the adoption of standards when choices are binary, social contagion explains the diffusion of cultural goods when choices are multiple. Together, the four structural features delineating cultural industries account for curious competitive dynamics prevalent in cultural markets, such as the notorious 10 : 90 proportionality (under which 10% of cultural goods account for 90% of the market), causal ambiguity about the reasons for success, and the formation of fashions. Six managerial recommendations are advanced, focusing on a criticial circulation point triggering self-sustaining diffusion patterns. Finally ‘project-based enterprises’ and ‘network forms of governance’ are identified as the organizational forms most suited to the dynamics of the cultural markets.  相似文献   
170.
Abstract  This study aims to explain similarity and difference in geographic proximity between elderly parents and their children in Korea and Japan. Using data sets from two nationally representative surveys conducted in Korea and Japan, this study examines the extent to which needs and kinship of elderly parents and regional constraints influence intergenerational coresidence and nearness.
Results highlight a complex feature of intergenerational relationship in Korea and Japan. Advanced economic and health conditions of Korean elderly parents increase the likelihood of living with children. For Japanese elderly parents, however, coresidence with children is significantly likely to occur in response to their disadvantaged economic status. These results suggest that the elderly Korean are more likely than the elderly Japanese to lack not only economic and health resources but also opportunities in obtaining family support in a time of need.
Characteristics of children, however, show a similar trend between the two societies. Both societies maintain a strong son preference for extended family living arrangement. Eldest children in both societies are more likely than their siblings to live with or near elderly parents. However, children of younger cohorts in both societies are significantly more likely than those of older cohorts to maintain a disperse geographic network indicating a significant change in family attitude among different cohorts.
Finally, this study finds a more disperse family network among rural elderly parents than urban elderly parents in both societies reflecting the fact that massive rural-to-urban migration of young population has contributed to geographic segregation of kinship in these societies.  相似文献   
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