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.     

加强会计诚信建设 提高会计信息质量

会计信息是国家的宏观经济管理部门、企业经济管理部门及其他方面进行决策的依据。会计信息真实客观与否，直接影响着企业经营管理、国家宏观调控、广大股东的投资决策，势必影响市场经济的有效健康发展。从根本上建立一套与市场经济相适应的会计信息质量保障体系势在必行，而整个体系的建立和健全是一个任重而道远的过程。在这个过程中，会计诚信也成了整个市场经济发展的职业道德规范，笔者就此谈谈几点看法。     

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.     

西部教育发展战略初探--以江苏"教育强省"的实践经验为鉴

西部地区教育水平的落后制约了其人力资源的开发,也制约了其经济发展.借鉴江苏"教育强省"的成功经验,西部教育应切实转变教育观念,为教育的发展奠定思想基础;因地制宜发展教育,为教育的发展建构体制框架;建立多元的投资机制,为教育发展提供资金保障;促进教育与经济的互动发展,为教育的发展挖掘潜力.     

加强企业统计基础工作初探

文章提出规范和加强企业统计基础工作是确保源头数据质量的需要,并通过对企业统计工作的现状、存在的问题、统计基础工作薄弱的原因进行分析,提出了加强和改进企业统计工作的几点建议。     

生活垃圾堆肥处理技术发展的几点思考

结合多年来在生活垃圾管理特别是堆肥厂的日常运行管理方面的经验，阐述了目前我国生活垃圾堆肥处理技术应用现状和堆肥厂实际运行过程中存在的具体问题，并对今后堆肥技术的发展提出几点建议，即：正确综合评价垃圾堆肥技术，给予垃圾堆肥技术正确定位，选择合理堆肥工艺，充分发挥垃圾堆肥的优势，提高堆肥质量，开拓堆肥产品市场是今后垃圾堆肥技术发展的关键。     

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。