视频业务识别方法综述

视频用户体验的质量要求给网络传输带来了巨大挑战，未来的虚拟现实/增强现实(Virtual Reality/Augmented Reality，VR/AR) 视频业务则对交互时延提出了更高要求。视频业务识别是网络运营商及视频业务提供商对视频进行优先网络资源分配和自适应速率控制的基本前提。综述了业务识别领域的一般研究方法及其对视频业务的具体应用。首先，总结了每种业务识别方法的工作原理，对比了这些方法应用于视频业务时的优缺点及在准确率和召回率指标上的识别性能;然后，特别介绍了可以提升识别准确率和计算性能的特征选择算法;最后，阐述并分析了高吞吐量网络分类速度不够、无成熟视频业务识别平台和样本分布不均衡等视频业务识别面临的挑战，并针对现有业务识别方法存在的问题，给出了引入移动边缘计算、基于端口的方法串联其他识别方法等可能的解决方案。     

Dynamic management of aircraft stand allocation

This paper aimed to present an original approach for solving the aircraft stand allocation (SA) problem dynamically when due to operational disturbances, the planned allocation cannot be accomplished. The proposed Multiple-criteria Dynamic Stand Allocation (MDSA) method uses fuzzy logic to support decision-making under uncertainty. The MDSA method provides effective solutions in a short time, necessary for traffic management in case of delays, emergency, and untypical cases. It considers partially conflicting points of view of different airport users (airport managers, air traffic controllers, airlines, handling agents, and passengers) and may significantly support managers on the SA problem. The approach proposed can also be used for creating an initial SA plan for a considerable number of aircraft.     

Optimizing a portfolio of mean-reverting assets with transaction costs via a feedforward neural network

Optimizing a portfolio of mean-reverting assets under transaction costs and a finite horizon is severely constrained by the curse of high dimensionality. To overcome the exponential barrier, we develop an efficient, scalable algorithm by employing a feedforward neural network. A novel concept is to apply HJB equations as an advanced start for the neural network. Empirical tests with several practical examples, including a portfolio of 48 correlated pair trades over 50 time steps, show the advantages of the approach in a high-dimensional setting. We conjecture that other financial optimization problems are amenable to similar approaches.     

Stock price crash risk and CEO power: Firm-level analysis

This study examines the impact of stock price crash risk on future CEO power. Using a large panel sample with 17,816 firm-year observations, we posit and find a significant negative impact of stock price crash risk on CEO power, suggesting that CEO power becomes smaller after stock price crashes. We also find that our results are stronger for firms with female CEOs and are largely driven by firms with shorter-tenure CEOs. In addition, we find that the significant negative impact of stock price crash risk on CEO power is diminished for firms with strong corporate governance. Our study responds to the call in Habib, Hasan, and Jiang (2018) by providing more empirical evidence on the consequences of stock price crash risk.     

New accounts: Towards a reframing of social accounting

This paper is a speculative and exploratory essay on the emerging field of social accounting. In essence, the paper explores whether the fact that most social accounting has, traditionally at any rate, being promulgated by accountants might be a partial explanation for its self-disciplining limitations and, arguably, its weak inroads into discourse and practice. Through the lens of Erik Olin Wright's work, the paper reconsiders the potential of the social accounting project(s) and argues for the importance of accounts as a means of interstitial transformation as a complement to the traditional privileging of accounts directed towards symbiotic transformations.     

Market power in CEE banking sectors and the impact of the global financial crisis

The aim of this study is to undertake an up-to-date assessment of market power in Central and Eastern European banking markets and explore how the global financial crisis has affected market power and what has been the impact of foreign ownership. Three main results emerge. First, while there is some convergence in country-level market power during the pre-crisis period, the onset of the global crisis has put an end to this process. Second, bank-level market power appears to vary significantly with respect to ownership characteristics. Third, asset quality and capitalization affect differently the margins in the pre-crisis and the crisis periods. While in the pre-crisis period the impacts are similar for all banks regardless of ownership status, in the crisis period non-performing loans have a negative effect and capitalization a positive effect only for domestically-owned banks.     

城市轨道交通直流牵引供电系统接触网残压

对于城市轨道交通来讲,在运行的过程中,直流牵引供电系统是使用最为主要的部件之一。在该系统应用的过程中,接触网残压问题是较为严重的问题,也是当前所出现问题当中比较普遍的一种。对于直流牵引供电系统来讲,当出现接触网残压问题时,可能会对人的生命安全造成严重威胁,同时也会使检修施工和接触网送电保护闭锁等相关工作受到影响,严重拖慢工作进度。因此,论文通过测试、仿真分析和模拟验证等方法,对城市轨道交通直流牵引供电系统接触网残压问题进行了研究与论述。     

Is job control always beneficial? Exploring its nonlinearity in creativity and in-role performance

This study draws on resource allocation theory to examine the relationship between job control and two kinds of job performance, namely employee creativity and in-role performance, as well as to investigate whether supervisor encouragement of creativity moderates these two potentially nonlinear relationships. To test the proposed model, we collected data from 234 employees in Indonesia. The results show that job control has an inverted U-shaped relationship with employee creativity, but a U-shaped relationship with in-role performance. Supervisor encouragement of creativity moderates both relationships, such that the control–creativity relationship becomes U-shaped, while the control–in-role performance relationship becomes inverted U-shaped when supervisor encouragement of creativity is high. Implications for managers on how to provide resources to employees are discussed.     

The effect of inspections,rotations and client preferences on staffing decisions

With increased regulatory focus on audits and concerns about whether audit regulation is achieving its stated aims, it is timely to investigate how regulator inspection of audit files and partner rotations may be affecting staffing decisions. This is an important issue, which affects all audits, as the calibre of staff allocated across engagements impacts the quality of audit work delivered. This study reports the results of an experiment where auditor participants allocate staff across two audits, where regulation anticipated (none, inspection, rotation) and a client request for the best staff (absent, present) are manipulated between‐subjects. We find that auditors allocate lower calibre staff when neither an inspection nor rotation is anticipated than when either is anticipated. When an inspection is anticipated, auditors allocate staff with more knowledge and compliance skills. When a rotation is anticipated, auditors allocate staff with more people skills. A client request for the best staff only has an effect when a partner is due to be rotated, where auditors allocate staff with more people skills in response to the client request. Our findings provide greater understanding of staffing decisions, which may affect audit quality if concerns around audit inspections and partner rotations are perceived by auditors as more important than the underlying risk or complexity of an engagement when allocating staff.