Managing uncertainty in on-demand air travel

Fractional management companies (FMCs) that provide on-demand air travel services experience frequent changes in aircraft availability and flight requests. We propose scheduling heuristics which are both cost-effective and persistent (i.e., close to the original schedule) to address the uncertainty. The heuristics include pro-actively enforcing idleness of aircraft in creating the original schedule, strategically repositioning aircraft to serve yet-unknown demand and dense scheduling. Computational experiments are conducted in a simulator that mimics FMCs’ daily operations. Simulation results quantify the value of each heuristic, which can be easily incorporated into existing computational methods used in FMCs for static scheduling problems.     

A hybrid parallel genetic algorithm for yard crane scheduling

This paper aims at postulating a novel strategy in terms of yard crane scheduling. In this study, a dynamic scheduling model using objective programming for yard cranes is initially developed based on rolling-horizon approach. To resolve the NP-complete problem regarding the yard crane scheduling, a hybrid algorithm, which employs heuristic rules and parallel genetic algorithm (PGA), is then employed. Then a simulation model is developed for evaluating this approach. Finally, numerical experiments on a specific container terminal yard are used for system illustration. Computational results suggest that the proposed method is able to solve the problem efficiently.     

大唐克旗#3机组电气整套启动试验危险点分析

发电机组的电气整套试验是一种综合性试验,主要包括发变组短路试验、发变组空载试验、励磁系统试验、同期系统试验等试验项目。在整个电气整套试验的过程中,该机组存在着一些可能导致机组试验失败和人身设备安全的危险点,通过对这些危险点的分析处理,可以为其他试运机组出现同类现象提供借鉴和参考。     

中小企业的数据保护细节

信息技术的高速发展,大力促进了中小企业的发展,但也带来了一系列数据使用上的安全隐患.当前,破坏中小企业数据保护工作的手段层出不穷.因此,如何关注细节,从源头上做好数据保护,成为广大用户在使用计算机及其相关产品时极其关注的问题.文章例举了一些常见的数据泄密细节,并提出了一些行之有效的应对方法.     

日本学者眼中的"靺鞨"——以石井正敏和小岛芳孝的研究为中心

渤海国是7～10世纪存在于我国东北地区的一个地方民族政权。繁盛期的渤海国疆域辽阔，广涉现在我国的东北地区、俄罗斯远东滨海地区、朝鲜半岛北部等。因此，渤海国研究在申、日、俄、韩、朝等国都受到广泛的关注。把目光锁定在日本，从代表性学者的研究中，观察他们是如何看待“靺鞨”及“靺鞨国”的，从深层比较中日文化的差异，最终达到理解日本文化的目的。     

交易成本与新型农村合作医疗制度可持续发展

新型农村合作医疗制度的试点极大地推进了我国农村医疗保障制度的构建过程,但是该项制度推进并不顺利。本文试从交易成本理论视角,分析当前新农合制度存在较高的交易成本导致制度创新不足。在此基础上,本文提出要使新农合制度可持续发展,政府必须从制度完善和机制创新两个方面降低交易成本,以提高新农合制度绩效。     

基于长效机制的公路“绿色通道”政策探析

公路的“绿色通道”一般是指为装载生鲜瓜果蔬菜、活畜活禽等车辆开通的一条快捷、免费或者优惠的通道。该政策是政府降低鲜活农产品运输成本，提高鲜活农产品流通效率，促进农村经济发展的一项重要举措。在刺激经济和关注“三农”问题的大背景下，“绿色通道”政策必将长期持续。对此，公路经营企业必须主动配合，承担责任。     

Isolating the effect of disclosure on information risk

This study examines companies with two classes of shares that entitle their holders to identical cash flow and voting rights but that are available to mutually exclusive sets of investors: A shares to domestic investors and B shares to foreign investors. Price differences between A and B shares are higher in firms with a greater disparity in the disclosures that they make to domestic and foreign investors. This association is more pronounced when the cost (benefit) of information transfer is higher (lower). The results suggest that disclosure disparity creates meaningful differences in investors' average information precision across A and B shares and thus influences the cross-sectional variation in price differences.     

The Effect of Import Competition on Firm Productivity and Innovation: Does the Distance to Technology Frontier Matter?

How does foreign competition affect growth and innovation in China? Using our unique measures of proximity of Chinese firms and industries to the world technology frontier, we find that despite vast sectoral heterogeneity, Chinese manufacturing industries have undergone rapid technological upgrading over the period of 2000–06. The distance to the world production frontier of firms and industries plays an important role in shaping the nexus between the competition pressure from foreign imports and domestic firms' growth and innovation behaviour. Our results support the theoretical predictions of Aghion et al. (2005, The Quarterly Journal of Economics, pp. 701–728) that import competition stimulates the domestic firms' productivity growth and R&D expenditure if firms and their industries are close to the world frontier, but discourages such incentives for laggard firms and industries. The two forces highlighted by the model operate for imports under the ordinary‐trade regime, for collective and private firms, and for imports originated from high‐income countries. Our findings are robust after controlling the influence of foreign investment, the reverse causality of regressors and the short‐term business cycle fluctuations.     

我国网上银行发展现状、存在问题及相关建议

网上银行服务是未来银行服务发展的必然趋势,本文讨论了国内外网上银行的发展现状,分析我国目前网上银行发展存在的问题,并提出了相应的建议。