Exploring the factors that drive consumers to use contactless delivery services in the context of the continued COVID-19 pandemic

The spread of the COVID-19 pandemic has resulted in the launch of contactless delivery services. This research integrates resource matching, service quality evaluation, and perceived value theories to explore the factors that promote the use contactless delivery services. The data was obtained through questionnaire surveys, and research hypotheses were verified through the structural equation modelling approach. With the exception of convenience, the results show that privacy, reliability, security, and flexibility have a significantly positive effect on consumers' intention to use “contactless” delivery services through consumers' perceived value. This study contributes to the literature by introducing theoretical frameworks from various paradigms and enriches the academic research on existing theoretical structure models. It also helps optimize resource allocation and realize the social environment related to coexisting with the COVID-19 pandemic.     

Forecasting turning points in tourism growth

Tourism demand exhibits growth cycles, and it is important to forecast turning points in these growth cycles to minimise risks to destination management. This study estimates logistic models of Hong Kong tourism demand, which are then used to generate both short- and long-term forecasts of tourism growth. The performance of the models is evaluated using the quadratic probability score and hit rates. The results show that the ways in which this information is used are crucial to the models’ predictive power. Further, we investigate whether combining probability forecasts can improve predictive accuracy, and find that combination approaches, especially nonlinear combination approaches, are sensitive to the quality of forecasts in the pool. In addition, model screening can improve forecasting performance.     

基于遥感蒸散数据的农田灌溉水平评价和设施建设分区研究

[目的]利用遥感蒸散数据快速评价农田年度灌溉水平,及时获取基本农田建设成效,为农田灌溉设施分区建设提供参考。[方法]以黑龙江省海伦市为研究区,MOD16蒸散产品为数据源,计算有效灌溉量、灌溉需水量和作物缺水指数,分别对研究区2013年的旱地和水田灌溉水平进行评价,并将评价结果与农田水利设施作用分值图进行叠加分析,在此基础上进行基本农田灌溉设施建设分区。[结果]2013年海伦市耕地灌溉水平整体较高,区域间建设水平差别较大,可划分为4个级别。其中1级和2级灌溉水平的地块面积比例可达78.06%,地域分布上看,北部、西部、中部乡镇灌溉水平较高,东南部乡镇灌溉水平相对较低。叠加得出8种组合类型,分为设施修建型、设施提升型和设施维护型3种分区类型。[结论]研究为高标准农田建设提供了更详细的农田灌溉水平评价方法和更具差别化的农田灌溉设施建设策略。     

Does income inequality increase marginal propensity to consume?

This article empirically investigates the effects of income inequality on the marginal propensity to consume (MPC), using panel data of 22 OECD countries over the period 1994–2015. We find that MPC increases dramatically as income inequality increases. In subsample analyses, the MPC of a high inequality group is more than twice that of a low inequality group.     

认知型飞蜂窝网络中的子信道分配与功率控制

为了解决宏蜂窝与飞蜂窝构成的两层异构网络上行干扰与资源分配问题，提出了一种在认知型飞蜂窝的双层异构网中结合子信道分配和功率控制进行资源分配的框架。通过对异构网中跨层干扰问题进行分析与建模，将求解最优子信道分配矩阵和用户发射功率矩阵作为干扰管理问题的解决方法。模型中认知型飞蜂窝网络子信道和飞蜂窝网络用户构成非合作博弈，双方利用效用函数最优值进行匹配，构成初始信道分配矩阵；再由接入控制器根据接入条件从初始信道分配矩阵中筛选用户，并优化接入用户的发射功率矩阵，得到最优子信道分配矩阵和功率矩阵。仿真结果表明，优化框架提高了双层异构网络中飞蜂窝网络用户的吞吐量和接入率，降低了异构网中跨层干扰。     

Network ties and export propensity of Vietnamese small and medium enterprises

This paper investigates the impacts of different network ties on export propensity of Vietnamese small and medium enterprises (SMEs) in the manufacturing sector. Using data from a survey of over 2,600 manufacturing SMEs in 2015, we found that social networks contribute positively to the export propensity of SMEs, while the size of business networks negatively associates with the likelihood of export. However, bank networks and political networks are not significant for the propensity to export of Vietnamese SMEs. We discuss the results in detail and offer recommendations for SME owners, managers and policy makers.     

电子商务技能型人才需求与高职教育培养匹配研究

产业转型升级发展对专业技能型人才的需求发生变化,作为技能型人才重要培养主体的高职院校,面临着如何培养新时代高素质技能人才的挑战。通过招聘大数据挖掘电子商务技能型人才的需求特征,同时调研相关高职院校电子商务专业人才培养现状,分析供需匹配度。结果表明:电商企业需要德技并修的高素质技能型人才,而高职院校的课程体系以专业技能、商务技能等硬技能教学为主,忽视综合素养软技能教育,同时,高职院校电子商务专业课程开设未能根据行业技术更新和产业转型发展及时调整。基于研究结果,从课程体系建设、校企合作深化、工匠精神培育等方面提出相关建议。     

Time-varying inter-urban housing price spillovers in China: Causes and consequences

The spatial spillovers of housing prices across regions are well documented by a large body of previous studies. This paper tries to investigate the dynamic (time-varying) evolution of spatial interactions and their underlying driving factors intensively. Using a recently developed Generalized Autoregressive Score (GAS) model, this paper examines the time-varying spatial spillovers of housing prices in 70 major and median cities of China from 2006 to 2019. We find that the GAS model can well capture the impact of time-varying critical events of Chinese real estate market on the whole. However, different regions display heterogeneous variation patterns over time. Further investigation shows that inter-regional labor mobility and trades are two major channels, accounting for 1.25% and 2.58% of the monthly standard deviations of spatial spillover effects from one city to another, respectively. We also characterize and distinguish between three time-varying patterns of spatial spillovers within different regions of China. Our results shed lights on the understanding of spatial spillovers across regional real estate markets across different city network structures within China.     

The impact of international diversification on credit scores: Evidence from the UK

Despite the great deal of previous research into international diversification, we know little about the impact of international diversification on firms’ credit scores. Drawing upon the resource-based view and transaction cost economics, we examine the relationship between international diversification and credit scores by using a large sample of 6,557 UK firms between 2016 and 2017. We find an inverted U-shaped relationship between international diversification and firms’ credit scores, indicating that the effect of international diversification on credit scores is initially positive but becomes negative with over-diversification. In addition, we find that R&D intensity positively moderates the relationship between international diversification and credit score, implying that the credit scores of highly diversified firms improve as they increase their investment in R&D. Further analysis suggests that a firm’s credit score becomes less dependent on international diversification for large firms, firms in concentrated industries, firms in the manufacturing sector, and firms distant from key metropolitan areas, such as London.     

广义空间调制系统的正则化OMP检测算法

在广义空间调制（GSM）系统中，最大似然（ML）检测可以取得最优的检测性能，然而其计算复杂度随激活天线数的增加急剧增长。针对这一问题，提出了一种基于稀疏重构理论的低复杂度检测算法——正则化正交匹配追踪（ROMP）算法。该算法首先根据信道矩阵和当前残差的内积选取多个候选激活天线索引，接着对候选天线索引按正则化标准进行可靠性验证，剔除错误索引，缩小信号的搜索空间，最后通过求解最小二乘问题估计信号。仿真结果表明，与经典的正交匹配追踪（OMP）算法相比，所提算法以少许复杂度的增加为代价极大提升了检测性能，能够在检测性能与复杂度之间取得更好的折中。