固定效应部分线性变系数面板模型的快速有效估计

本文将最小二乘支持向量机(LSSVM) 和二次推断函数法(QIF) 相结合，为个体内具有相关结构的固定效应部分线性变系数面板模型提供了一种新的快速估计方法；在一定的正则条件下，论证了参数估计量的渐近正态性和非参数估计量的收敛速度；采用Monte Carlo模拟考察了估计方法在有限样本下的表现并将估计技术应用于现实数据分析。该方法不仅保证了估计的有效性和统计推断力，而且程序运行速度得到较大幅度提升。     

Minimization of passenger takeoff and landing risk in offshore helicopter transportation: Models,approaches and analysis

Offshore petroleum industry uses helicopters to transport the employees to and from installations. Takeoff and landing represent a substantial part of the flight risks for passengers. In this paper, we propose and analyze approaches to create a safe flight schedule to perform pickup of employees by several independent flights. Two scenarios are considered. Under the non-split scenario, exactly one visit is allowed to each installation. Under the split scenario, the pickup demand of an installation can be split between several flights. Interesting links between our problem and other problems of combinatorial optimization, e.g., parallel machine scheduling and bin-packing are established. We provide worst-case analysis of the performance of some of our algorithms and report the results of computational experiments conducted on randomly generated instances based on the real sets of installations in the oil fields on the Norwegian continental shelf. This paper is the first attempt to handle takeoff and landing risk in a flight schedule that consists of several flights and lays ground for the study on more advanced and practically relevant models.     

Varieties of political support in emerging democracies: A cross-national analysis

Political support is a multidimensional construct encompassing evaluations of political leaders and institutions (specific support) as well as adherence to basic regime principles (diffuse support). Scholars have traditionally assumed that diffuse and specific support are driven by different forces and evolve largely independently. Prior empirical work, however, has struggled to untangle the two support dimensions and focused predominantly on cross-national differences, ignoring their dynamics. This paper develops an analytical and empirical approach to examine the levels and dynamic interplay of both support dimensions and estimate their determinants, applying it to South American democracies between 1996 and 2015. Contrary to received wisdom, we show that both dimensions are quite volatile and closely linked in this region. In particular, negative economic shocks not only undermine support for government actors, but also fuel democratic disenchantment. Nonetheless, while regime support is rather fickle in South America, it can be ultimately resistant to performance fluctuations.     

Public relations and artificial intelligence: It’s not (just) about robots

Organizations of all kinds, as well as their in-house or agency public relations teams, increasingly co-opt Artificial Intelligence (AI) to enhance their capabilities. This paper examines a relatively new topic that has received little scholarly attention: the growing relationship between AI and public relations. It outlines several key roles that AI may play in future, based on trends in other industries, and considers the implications for public relations practitioners, their clients and employers. It therefore launches a dialogue about the diversity and extent of AI’s uses in public relations practice. The paper argues that, to date, commentators have placed too much emphasis on AI’s potential for task automation; AI’s broader technological, economic and societal implications for public relations warrant greater critical attention. This does not imply that practitioners need become expert technologists; rather, they should develop a sufficient understanding of AI’s present and potential uses to be able to offer informed counsel.     

信息时代的翻译工具

我们正处于一个多语言网络的信息时代,如何有效地使用现代化手段来突破人们之间的语言障碍,成为了全人类面临的共同问题.翻译是克服语言障碍的有利手段.信息时代的翻译工具有:机器翻译系统、因特网上的语言翻译资源、CD-ROM上的语言翻译资源、计算机辅助术语管理系统、双语对应语料库、翻译记忆软件和本土化软件工具、机助翻译系统.掌握了信息时代的这些翻译工具,就可以大大地提高翻译的效率,满足信息时代对翻译的迫切需要.     

关于科学发现机器的研究

本文阐述了科学发现的两个判据,在知识存贮有劣性原理的基础上,提出了知识存贮不完全性原理,指出存在一类逻辑上具有非放大性,但认识论上具有放大性的演绎发现机器。在休谟问题逻辑学范围内不可解原理的基础上,论证了不存在通用的归纳发现机器,但建立局部合理的、有效的、完备的归纳发现机器是可行的。最后,本文描述了科学发现机器的结构,并在文献的基础上,描述了一种同时具有发生与评价功能的归纳发现机器并论证了它的合理性。     

实践性教学模式在机械制造技术基础课程中的应用

机械制造技术基础课程是重要的专业基础课程。结合课程理论教学和实践应用特点,从现场实践、项目促进、毕业实习和毕业设计等环节,探索了该课程的实践性教学模式,做到现场实践促进理论学习,科研促进教学,极大地激发了学生学习的积极性和主动性,使学生能深入理解、掌握和运用基本知识和基本技能,丰富了学生的专业知识,培养了学生独立思考和解决问题的能力,教师完成了教学任务及部分科研工作,实现了实践、科研及综合运用促进本科生教学的新模式。     

One-machine scheduling to minimize mean tardiness with minimum number tardy

In this paper the one-machine scheduling problem with the objective of minimizing the mean tardiness subject to maintaining a prescribed number of tardy jobs is analysed. An algorithm for solving this problem is presented. It is proved that the schedule generated by the proposed algorithm is indeed optimal.     

Impact of investing in quality improvement on (Q,r, L) model involving the imperfect production process

This paper investigates the impact of quality improvement on the modified lot size reorder point models involving variable lead time and partial backorders. The formulated models include the imperfect production process and an investing option of improving the process quality. The objective is simultaneously optimizing the lot size, reorder point, process quality level and lead time. We first assume that the lead time demand follows a normal distribution, then relax this assumption to consider the distribution-free case where only the mean and standard deviation of lead time demand are known. An algorithm procedure of finding the optimal solution is developed, and two numerical examples are given to illustrate the results.     

The impact of random machine unavailability on inventory policies in a continuous improvement environment

There are production situations where a production facility (e.g. a machine) is used intermittently to produce lot sizes of certain products. Upon completion of production run, the facility may not be available for a random amount of time due to several reasons, such as: the facility needs to be maintained and the maintenance time is random due to unforeseen circumstances; or that the facility is leased by different manufacturers and the demand for the facility is random. As a result of machine unavailability, stock-out situations might arise. This paper extends the work of Abboud et al . (2000, Computers and Operations Research , 27 , 335-351) by assuming learning and forgetting in production. A new mathematical model is developed with numerical examples and sensitivity analysis provided. Furthermore, this paper determines how the overall inventory cost is influenced by the nature of the random variable that represents the unavailability time of the production facility.