Diversification in Portfolios of Individual Stocks: 100 Stocks Are Not Enough

We examine returns and ending wealth in portfolios selected from 1,000 large U.S. stocks over a 20‐year holding period. Shortfall risk, the possibility of ending wealth being below a target, is a useful metric for long horizon investors and is consistent with the Safety First criterion. Density functions obtained from simulations illustrate that shortfall risk reduction continues as portfolio size is increased, even above 100 stocks. A slightly lower risk can be achieved in small portfolios by diversifying across industries, but a greater reduction is obtained by simply increasing the number of stocks.     

最后贷款人政策与银行危机管理

最后贷款人政策是银行危机管理的一个重要手段 ,也是银行安全网的主要组成部分。本文首先介绍了最后贷款人的传统理论 ,讨论了该机制在化解系统风险中的作用及其可能产生的道德风险问题。然后文章探讨了最后贷款人在现实中面临的一些挑战。最后 ,作者对中国人民银行的政策实践作了一个简要的评价     

核电发展趋势和我国核电产业化

该文回顾了本世纪核电发展的三个时期取得的成就和教训 ;展望了新世纪核电的机遇和挑战 ;分析了两种核电技术路线的技术特征及发达国家和发展中国家的市场前景 ;提出了对我国核电产业化的一些看法     

Strategies to detect and reduce counterfeiting activity

While at one time counterfeit products were largely restricted to watches, designer apparel, and movies, today counterfeiting is a major problem in such diverse product categories as pharmaceuticals, automotive parts, and computer software. There are four distinct types of counterfeits: knockoffs, counterfeits that are reverse engineered from genuine goods, goods produced by outsourced suppliers on “third shifts,” and goods that do not meet a manufacturer's standards but are not properly labeled as seconds or destroyed. The quality of some counterfeits is so good that some major retailers have unknowingly purchased counterfeits. But while there are new forms of counterfeit goods, there are also new strategies for combating counterfeiting. This article describes how to detect and reduce counterfeiting activity, via a plan which consists of four steps: (1) developing early warning signals of counterfeiting; (2) budgeting to monitor, deter, and remove counterfeits; (3) using demand-side strategies to deter counterfeiting; and (4) using supply-side strategies to deter counterfeiting.     

安全人机工程学教学改革的探索与研究

安全人机工程学的教学内容要切合教学对象的培养目标,展现学科发展前沿,适当增加煤矿安全人机工程学案例与实践,提高学生的实践能力。教学方法应多样化,多种教学方法有机结合,充分发挥学生的积极性、主动性,实现课堂教学的高效开展。课程考核力求公开、公平、公正,并适当加大课堂综合表现的比重,为良好的课堂教学的实施保驾护航。     

The impact of the Covid-19 pandemic on customer experience design: The hotel managers’ perspective

This research responds to calls for research on the devastating impact of the Covid-19 pandemic on the hospitality industry by investigating how hotel managers are designing safe customer experiences. Specifically, this study examines the measures adopted in high-end and luxury hotels and identifies the effects of such measures on the intended (or planned) experience. Based on thematic analysis of interviews with hotel managers, this study identifies seven safety measures: hygiene and protection, internal work reorganization, servicescape reorganization, investments in technology and digital innovations, customer wait time reorganization, staff training, and updated communication. These measures are expected to affect the intended experience in terms of reassurance, quickness, intimacy, and proximity, as emerged from correspondence factor analysis. Based on these results, this research proposes a model for safe customer experience design and suggests practical implications to help hotel managers formulate strategies aimed at customer experience creation under safe conditions.     

Attitude towards immigrants and security: Effects on destination-loyal tourists

This study was conducted in the midst of a surge of undocumented immigrants into a popular seasonal migrant destination in the U.S. and the subsequent state response of adding security forces. Factors examined include the effects of the role of media in shaping perceptions about security forces, perceptions about security force effectiveness, perceptions of undocumented immigrants and political orientation. The study of 413 respondents found that attitudes toward undocumented immigrants affect felt safety in the region, likelihood of recommending and returning to the region. Perceptions of the effectiveness of the security forces were important in affecting likelihood of recommending the region to others but not return intention. These and other findings contribute significantly to the scant research on both effectiveness of crises management responses and on effects of perceptions of undocumented immigrants on traveler behavior.     

惩罚性赔偿导向的生命全价值评估研究

基于寿命周期各阶段生命价值的特点,综合运用成本法、收益法、市场法,从生命物质价值、生命精神价值、惩罚性赔偿的生命基础价值与生命保障价值四个方面分项评估生命全价值。选择各阶段有代表性的生命全价值,同时提取惩罚性的安全公益基金作为预防性安全投入,实现既可维护受害者的生命价值,又能促进可持续的安全投入。     

无线局域网安全性的探讨

随着无线局域网应用领域的不断拓展,无线局域网受到越来越多的威胁,本文研究了现阶段无线局域网面临的主要安全问题,并介绍了相应的解决办法。     

铁路调车作业安全评价指标体系应用研究

在分析铁路调车作业安全管理特点的基础上,基于科学性、系统性、可操作性、独立性、动态性的设计原则,从人员因素、设备因素、环境因素3个方面构建了铁路调车作业安全评价指标体系.结合基于熵权的未确知测度方法,以广通站为实例,应用铁路调车作业安全指标体系进行评价.结果表明:该指标体系能够较好地反映车站调车作业安全状况.