机场地面保障服务车辆协同调度和仿真优化

为实现大型机场地面保障服务高效化、智能化运行管理，通过研究多航班、多种地服车辆、多车场、带容量时间窗的复杂车辆路径规划问题，构建地服资源协同调度模型。结果表明：根据航班到达规律和机位分布情况，基于分解的高维进化算法求解效果较好，得到车辆使用数少、行驶距离短、超出时间窗惩罚函数最小和任务均衡的四维多目标优化问题的调度优化方案；通过Anylogic仿真软件验证，可实现机位占用情况、车辆使用情况动态分配和监控。     

Twenty years of Hong Kong and Macao under Chinese rule: being absorbed under ‘one country,two systems’

This paper examines the implementation of ‘one country, two systems’ (1C2S) in the two former Western colonies, Hong Kong and Macao, as a policy innovation in managing inter-governmental relations of a large, diverse country like China. 1C2S embodies internal tensions because the Hong Kong and Chinese governments have multiple and often incompatible goals. After 20 years, these two special administrative regions (SARs) of China are gradually being absorbed.     

Automatic extraction of 1D barcodes from video scans for drone-assisted inventory management in warehousing applications

The widespread use of barcodes has significantly contributed to accurate, efficient and economic inventory management in warehouses and distribution centres. However, its efficiency has always been limited by the primary method of reading barcodes with a handheld laser scanner. Compared with this reading by line-of-sight at close proximity, vision-based barcode reading algorithms can further improve efficiency, particularly if accompanied by automated data collection platforms such as drones. This paper introduces algorithms that are able to automatically extract barcodes from video data, and verifies their feasibility and promise for inventory management in warehousing applications. Three key techniques corresponding to different recognition levels are proposed: For a known barcode region, a Harris corner detector and Hough transform-based algorithm is applied to quickly estimate the angle by which the frame area needs to rotate to orient the bars vertically for information extraction. Then, the idea of exploiting connectivity and geometry property of barcode areas is proposed to directly recognise multiple barcode regions in a single video frame to eliminate reading difficulties resulting from interactive influence of multiple juxtaposed barcodes, and to save computation time by only processing frame areas of interest for valid barcodes. In addition, a histogram difference-based fast extraction strategy is designed to further improve efficiency by reducing duplicate information processing. Finally, the performance of each technique is evaluated by analysing video data from a large logistics warehouse, demonstrating satisfactory performance in inventory management applications.     

Business-to-business selling in the post-COVID-19 era: Developing an adaptive sales force

The COVID-19 pandemic has changed how salespeople interact with customers and with business-to-business (B2B) organizations. Organizations must confront the shifts in how their salespeople operate. Recent research recommends firms develop an adaptive sales force to address disruptions like a pandemic and be prepared to meet such challenges in the future. Based on interviews with marketing and sales executives, we explore how firms have responded to these interconnected changes during the COVID-19 pandemic and offer insight into best practices deployed across industries.     

Model Comparison for Temperature-Based Weather Derivatives in Mainland China

Abstract:

In this paper, we provide a comparison of two models of temperature-based weather derivatives. The Alaton et al. model (2002) and the continuous-time autoregressive (CAR) model of Benth et al. (2007) are applied to temperature data from twelve cities in China. The objective is to determine which is the better model for temperature derivative modeling in Chinese cities. We found the CAR model to be more accurate in terms of normality of residuals and smaller relative errors. However, the shortcomings of both the Alaton et al. model and the CAR model are revealed in this study as well.     

大空间飞机修理厂房分层空调的可行性分析

本文以某大空间飞机修理厂房为研究对象,采用Airpak软件对其原始分层空调设计方案气流组织进行模拟,并对方案可行性进行评价。     

Is socially responsible investment useful in Mexico? A multi-factor and ex-ante review

The present paper continues the firsts reviews made to socially responsible investment in Mexico. We extended these reviews by using a non-parametric multivariate equality test, along with a multi-factor market cap model, and a Monte Carlo simulation. Our results show that the IPCS index, the IPCcomp and the IPC have a statistically equal mean-variance performance, suggesting that this sort of investment style (SRI) is a good substitute of the broad market investment style in the long term. Among the causes of this finding is the fact that the IPCS and the IPCcomp indexes have almost the same large and small cap stock concentration and the IPC index (a large-cap one) is not as diversified and mean-variance efficient as the former.     

The influence of remuneration on the behavior of hospital employees in Brazil

The study aimed to analyze the employee's perception of the remuneration systems in two major hospitals in Brazil, one managed by the government and the other by private investors. The sample considered 109 respondents, out of which 54 were from the private hospital and 55 from the public hospital. After data collection on the sample population, perception of remuneration was associated with occupation, gender, age and experience, as suggested by the Upper Echelons Theory. The results show that remuneration is viewed as an instrument of control and behavior or a learning-inducing mechanism; however, the perceptions of employees working in the health area and administrative area were different. These findings show that the influence of fixed pay is different not only for the employees of both areas, but also in relation to the public and private hospital management. It was found that gender is not a determinant factor of behavior and that there were no differences between younger and older employees as well as between more experienced and less experienced employees with respect to the effect of remuneration on behavior. There were no differences in relation to the type of hospital either. In general, the results emphasize the importance of remuneration as an instrument of control and management, either in the context of public or private organizations.     

The Effect of Board Diversity on Earnings Quality: An Empirical Study of Listed Firms in Vietnam

Previous studies have established that firms’ effectiveness can differ based on the differences among directors within a board, and between boards. However, studies have yet to establish the effectiveness of the diverse attributes of the board on firms’ quality of earnings in an emerging market setting such as Vietnam. This study investigates the effect of board diversity on earnings quality in a sample of Vietnamese listed firms. The two dimensions of board diversity measures in this study cover a wide range of structural and demographic attributes of board of directors, using a diversity‐of‐boards index (dissimilarities among firm boards, i.e., board structure) and a diversity‐in‐boards index (dissimilarities among directors within a board, i.e., demographic attributes of board members). Earnings quality is an aggregate measure compiled from four accounting‐based measures of earnings quality: accruals quality, earnings persistence, earnings predictability and earnings smoothness. We find a significant, positive linear relationship between diversity of boards and earnings quality, while the relationship between diversity in boards and earnings quality is non‐linear, with a U‐shaped curve.     

On an efficient multiple time step Monte Carlo simulation of the SABR model

In this paper, we will present a multiple time step Monte Carlo simulation technique for pricing options under the Stochastic Alpha Beta Rho model. The proposed method is an extension of the one time step Monte Carlo method that we proposed in an accompanying paper Leitao et al. [Appl. Math. Comput. 2017, 293, 461–479], for pricing European options in the context of the model calibration. A highly efficient method results, with many very interesting and nontrivial components, like Fourier inversion for the sum of log-normals, stochastic collocation, Gumbel copula, correlation approximation, that are not yet seen in combination within a Monte Carlo simulation. The present multiple time step Monte Carlo method is especially useful for long-term options and for exotic options.