Complex Network of Aviation E-Services in the Belt and Road Initiative: A Heuristic Study of Small Data based on Block Modeling

ABSTRACT

The aviation e-service system is an important part of support for business communication in regions covered by Belt and Road initiative. In exploring the role of airline companies in this system, we examine the structure of the network, which consists of airlines interconnections based on small data of individual attributes of aviation companies in aviation e-services, and study these interconnections across different groups using block modeling. The heuristic solution of airline companies in development of international communication and cooperation is further discussed. Among our policy implications for global managers, we suggest the enhancement of cross-regional cooperation among airlines.     

EMPIRICAL PERFORMANCE OF GARCH MODELS WITH HEAVY‐TAILED INNOVATIONS

We introduce a new type of heavy‐tailed distribution, the normal reciprocal inverse Gaussian distribution (NRIG), to the GARCH and Glosten‐Jagannathan‐Runkle (1993) GARCH models, and compare its empirical performance with two other popular types of heavy‐tailed distribution, the Student's t distribution and the normal inverse Gaussian distribution (NIG), using a variety of asset return series. Our results illustrate that there is no overwhelmingly dominant distribution in fitting the data under the GARCH framework, although the NRIG distribution performs slightly better than the other two types of distribution. For market indexes series, it is important to introduce both GJR‐terms and the NRIG distribution to improve the models’ performance, but it is ambiguous for individual stock prices series. Our results also show the GJR‐GARCH NRIG model has practical advantages in quantitative risk management. Finally, the convergence of numerical solutions in maximum‐likelihood estimation of GARCH and GJR‐GARCH models with the three types of heavy‐tailed distribution is investigated.     

深圳市线路板蚀刻废液中铜、砷、铅、汞、镉含量调查

对深圳市60家线路板企业含铜蚀刻废液中铜、砷、铅、汞、镉含量的检测结果显示:酸、碱性蚀刻废液铜含量范围分别为38.6～167.9g/L、53.7～171.8g/L,,通过测量比重推算铜含量适用于碱性废液但不适合酸性废液.56个样品可检出砷(大于3mg/L).56个样品未检出铅(小于5mg/L),其余4个铅含量偏高.所有样品汞、镉均未检出,含量分别小于4mg/L、0.3 mg/L.将各样品砷、铅、汞、镉含量实测值换算为铜含量100ga.时的相对值后发现,上述四元素在蚀刻废液中的正常值分别为＜12mgAs/L、＜5 mg Pb/L、＜4 mg Hg/L、＜0.3 mg Cd/L.     

浅谈企业房地产价值信息的背离与披露

房地产交易中企业财务报告反映的房地产账面价值与实际市场价值的背离程度大,造成了企业资产价值的“低估”。该文试图分析引起企业房地产账面价值与实际市场价值背离的原因,提出了财务报告使用者了解企业房地产实际价值的几种可操作方法。     

A note on the existence of unique equivalent martingale measures in a Markovian setting

Simple sufficient conditions for the existence of a unique equivalent martingale measure are provided. Furthermore, these conditions give us a handle on situations where an equivalent martingale measure cannot exist. The existence of a unique equivalent martingale measure is of relevance to problems in mathematical finance. Two examples of models for which the question of existence was unresolved are studied. By means of our results existence of a unique equivalent measure up to an explosion time is proved.     

国际电子商务中的语言差异问题及其解决策略

在电子商务的全球化过程中，各地区的语言、文化差异。给国际电子商务展开带来了一定的障碍，本文论述了语言问题产生的根源，并提出了相应的解决策略，以期对国内企业的未来发展有所助益。     

我国危险品物流管理对策研究

通过对我国危险品物流的现状分析,指出了加强危险品物流管理的必要性,并阐述了加强危险品物流管理的意义。在对国外危险品物流管理方法进行总结的基础上,分析了我国政府和危险品物流企业在危险品物流管理中的作用和相互关系,并提出了加强危险品物流管理的一些具体对策和措施。     

"按劳分配"在理论与实践中遇到的困难及其对策

文章在阐述我国个人收入分配制度确立的理论和实践依据的基础上，分析了“按劳分配”在理论与实践中遇到的难题，即“各尽所能”遇到的困难；劳动力成为商品与按劳分配的冲突；“劳”的理解问题；不同所有制、不同行业、不同职业、不同地区、城乡居民、高低收入群体收入差距不断拉大对按劳分配提出的挑战等，进而提出解决这些困难的主要对策。     

委托代理风险的多维标度与防范对策研究--来自复杂系统和博弈论的启示

委托代理风险是现代企业治理中的共性问题,由于传统研究侧重于契约关系的完善而缺乏对风险性质本身的深入解析,所以研究的结果可以改善代理关系, 但未必能有效防止风险.本文在对现代企业理论相关研究进行探讨的基础上,将研究的焦点从契约关系研究转向风险性质研究,从经济维、政治维、文化维、时间维四个角度对代理风险进行了深层次剖析,并针对代理风险的特性提出了相应的防范对策.     

网络化对高校“两课”教学的影响及其对策

计算机国际互联网在全球范围内的迅速发展和普及,改变了人们的思维和行为习惯,冲击着当代大学生的文化生活、思想观念和世界观,冲击着高校“两课”教学。高校“两课”教师应顺应潮流,主动占领思想政治工作的新阵地,加强高校“两课”教学改革,提高“两课”教学水平。