Corporate employment,red flags,and audit effort

U.S. regulatory agencies and congressional oversight committees have expressed concerns that auditors often neglect red flags embedded in the operating characteristics of firms that misstate their financial reports. This study examines whether labor employment decisions, a major part of a firm’s operations, help predict accounting improprieties and consequently play a role in audit planning and pricing. We find that negative abnormal employment changes are associated with a higher likelihood of subsequent financial restatements, accounting irregularities, and lawsuits related to accounting fraud, and generally require greater effort from auditors as manifested by higher audit fees and longer audit report lags. Positive abnormal employment changes are associated with subsequent restatements and longer audit report lags, but not associated with fraud or audit fees. Taken together, the results are consistent with auditors recognizing the individual misstatement risks pertaining to companies’ employment decisions. These results suggest that standard setters, regulators, and practitioners should devote more attention to operational statistics to identify potential red flags.     

Informed trade,uninformed trade and stock price delay

The probability of informed trading (PIN), a measure of information-based trading risk, has been broadly applied to empirical studies on asset pricing. However, it is still controversial whether PIN measures exclusively the risk of firm-specific private information or it also captures the private interpretation of market wide public information. This article examines the relevance of PIN to the delayed response of stock prices to market-wide information. We find that PIN significantly explains individual stock price delay even controlling for size, liquidity and risk, and low-PIN stock prices adjust to market information more rapidly not only because of a notably high level of informed trading but also an even much higher level of uninformed trading. Our findings support the notion that PIN also captures the private skilled interpretation of public common factor information by sophisticated investors, and provide new empirical evidence on how information-based trading affects the speed at which stock prices adjust to information.     

基于时延补偿的小小区多跳空口同步

在密集蜂窝异构网络中，小小区之间的时频同步是发挥小小区技术优势的重要条件以及网络系统正常运转的前提。传统的小区同步技术包括同步卫星辅助同步及IEEE 1588协议同步。为克服传统小区同步技术的不足，空口同步技术成为研究热点。在此基础上，提出了一种基于时延补偿的多跳空口同步机制，通过源小区空口同步信号(RISS)所在时帧位置来确定其同步等级，同时对源小区RISS的传播时延进行补偿，从而提高目标小小区同步精度。仿真表明，该方案在同步跳数为4时，定时同步误差仍可维持在1 μs以内，从而有效地提高了网络同步精度，并突破了同步跳数对空口同步技术的限制，扩大了空口同步范围。     

User-Driven Prioritisation Process (UDPP) from advanced experimental to pre-operational validation environment

When the European Air Traffic Management Network (EATMN) approaches its capacity limits at certain airports, generating increasingly costly delays to flights and for passengers, reducing the impacts on airlines and passengers will be essential. There are two ways to address such increases in delay and costs. One is to strive to augment the capacity to reduce both delays and costs. The other one, adopted in this paper, is to reduce the impact of the delay on airlines and passengers.The User Driven Prioritisation Process (UDPP) provides airlines with additional flexibility in planning within constrained situations where delays are allocated, beyond the current slot swapping process already implemented by the EUROCONTROL Network Manager (NM).The paper presents recent validation results. It summarizes earlier results in a simplified EATMN with one constraint and several AUs showing that UDPP could reduce the impact of that delays on AUs' direct operational costs by 58% on average, and improves passengers’ connections. The paper then describes a parallel validation activity including several trials with SWISS. It focuses on the most recent validation results in a pre-operational environment close to SWISS Operations Control Centre (OCC). The results revealed overall operational benefit up to 65% improvement for the airline; and an initial impact assessment on the EATMN -although limited to one UDPP in the EATMN and one airline using it- shows promising results for the on-going integration closer to operations.While limited due to the simplified network context, these results are encouraging to undertake more complete network impact studies as well as to move forward to environments that are more realistic, bridging towards deployment.     

Model of passenger behavior choice under flight delay based on dynamic reference point

Flight delay has always been a concern of scholars, but in previous studies, there has been little discussion of passenger behavior choice after flight delay. The paper based on the prospect theory, taking the Beijing-Shanghai route as an example, constructs the passenger behavior choice model under flight delay, and in order to explore the decision-making behavior of passengers with different attributes under different delay scenarios. The results show that the reference point of passengers' behavioral decision-making is dynamic due to different delay scenarios and passengers' attributes. For the same reason, passengers have different behavioral choices when encountering flight delay. Through empirical analysis, it is found that the choice of passengers based on prospect theory is in line with the actual choice of passengers. The choice model proposed in the paper can effectively describe the passenger's choice behavior.     

Managing Airline Passenger Satisfaction During a Delay: A Case Study Applying Consumerist Gap Concepts

Abstract

Delays occur quite commonly in airtransportation, due to the effects of weather, congestion, or technical problems. Lengthy delays often give rise to passenger complaints and demands for compensation. This paper firstly presents a general consumerist gap model of passenger satisfaction management, then applies its concepts to a batch of passenger correspondence which resulted from a very long delay. Passengers' letters to the airline were reviewed and analysed using con-sumerist gap approaches, following which discussions were held with senior airline managers to identify ways of improving responses to passengers during incidents such as the one presented in this case study.     

低信噪比下互相关时延估计器的FPGA实现

在时延估计算法中,相关法是一种经典的算法。时域互相关法可用来进行整数倍和非整数倍采样周期的时延估计,即使是在极低的信噪比（SNR）条件下,利用较多的数据也能获得准确和稳定的估计结果。为提高时延估计分辨率,给出了一种采用sinc函数对信号进行非整数倍采样周期延时的相关估计算法,通过仿真比较了未插值、两倍插值法和sinc函数延时法的估计精度和计算量,证明sinc函数延时法性能最优。基于现场可编程逻辑门阵列（FPGA）实现的改进型互相关时延估计器能够实现在低信噪比下时延差的准确估计。     

一类积分微分不等式的振动性

研究了一类二阶积分微分不等式的振动性问题。首先利用Lebesgue控制收敛定理研究了其正解的存在性;接着得到了其不存在正解的条件;最后通过讨论给出了其解振动的充要条件。     

基于外包的生产能力不足的供应链协调模型

文章以一个供应商与一个零售商组成的供应链为研究对象。其中,供应商生产产品的能力小于零售商的年需求量,此时供应商可以把自己缺失的这部分产品以一定价格外包给一个外部生产商,然后再把外包生产的产品重新供应给零售商,假设外部生产商允许原供应商货款延期支付一段时间。文章分别研究了在无外包与有外包协调两种情况下供应链的最优利润模型,并对协调前后利润进行了比较．结果表明外包可以提高供应链的利润,并且外包也是从供应链协调的观点解决供应能力不足的一个有效方法。同时还给出了根据延期支付时间来决策外包比例的条件。