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1.
The panel data analysis points to economic and social factors contributing to NOx, PM2.5, PM10, SO2, and VOCs in China’s 31 provinces. The spatial correlation analysis using Global and Local Moran’s I values indicates the existence of a significant and positive spatial autocorrelation with respect to environment, economy and energy, and the high spatial correlation is evident in the eastern region, covering the northern part of Yangtze River Delta, Huaihai Economic Zone, and the lower reaches of the Yellow River Economic Belt. The empirical estimation is performed through spatial lag and spatial Durbin models. All emitted air pollutants in 31 provinces have significant spatial dependence and strong spillover effects. There is an inverted U-shaped relationship between emitted air pollutants (NOx, PM10, VOCs, and PM2.5) and per capita GDP, which follows the EKC hypothesis. The relationship between SO2 and per capita GDP does not follow the EKC hypothesis. There is a positive relationship between pollutant emissions and coal consumption, which is consistent with current studies for various countries like Canada, Denmark, UK and US and regions like New York State. However, the effects of science and technology investment on air pollutants are mostly positive, which is not as policy expected.  相似文献   
2.
Air travelers can carry an infectious disease's pathogenic microorganism in their bodies and spread the disease from one country to another in a few days. To delay the spread, health screening stations may be set up at airport terminals to screen travelers. This research tested three different health screening strategies, each with a different combination of screening stations at trip origins, destinations and connecting airports. Discrete event simulations were performed, based on the 2014 to 2016 Ebola virus epidemic, with special focus on travelers from the West African countries traveling to the United States, including travelers who transferred flights at airports in European Union member states. The effectiveness of the screening strategies was analyzed in terms of correct detection, missed detection and false alarm rate. The results showed that exit screening at trip origins brought big improvements in the performance measurements compared to no screening. However, additional screening at the destinations and connecting airports contributed marginal benefits.  相似文献   
3.
The modern working environment is changing at a fast pace due to factors such as globalisation, digitalisation, and demographic trends. Taking an exploratory approach, this study examines how prevailing factors shaping the working world may influence the perception of business air travellers. Relevant factors are identified through a literature review, which results are confirmed by expert interviews (N = 11). Business travellers are surveyed (N = 67) at Munich Airport regarding their personal experiences and their evaluations of these identified factors. Their perceptions concerning the psychological and physical experience, digitalisation, age, and gender are examined in detail.Findings provide insights into the development of business air travel, with a focus on German business travellers. Despite the influence of advanced information and communications technology, survey results reveal that air travel might stay an essential part of the working world, as face-to-face meetings are not fully replaceable. Increasing multi-partner project work and flexible work structures could even lead into an increase of air travel. The study also delineates recommendations and research potential, such as the extension of the study in the light of the global COVID-19 pandemic. The question of how trends within the working world influence the perception of business related air travel is rarely studied. This study contributes to this gap in the scientific community.  相似文献   
4.
物流园区工商业态的不同而产生的不同的物流需求,再加上交通条件和运输方式的差别,使物流园区在功能上具有不同类型.成都市四大物流园区具有不同的工商业基础和交通条件,应发挥各自的区位优势,进行正确的功能定位,以错位发展实现互补共赢.  相似文献   
5.
铁路运输客货管理机制的探讨   总被引:5,自引:2,他引:3  
随着我国加入WTO和铁路全面参与运输市场竞争,必须尽快构建适应市场需求的铁路客货管理的动力机制和运作机制,以激发企业和员工搞好营销的内在活力,同时要构建铁路客运和货运的服务质量评价指标,以及相应的质量监督和考核管理办法,做到各项管理活而不乱、管而不死,使铁路客货运输服务质量不断提高,以满足不断增长的经济和社会发展需要。  相似文献   
6.
建立铁路公益性运输补偿机制的探讨   总被引:1,自引:0,他引:1  
铁路公益性运输超越了企业的职能范围,企业应当得到国家补偿。为此,建议按照依法、据实补偿原则,以税收抵扣方式进行补偿,以利于铁路运输企业的积累和发展。  相似文献   
7.
在对我国铁路技术站运输分析手段和管理信息资源进行分析的基础上,提出技术站运输分析管理信息系统的设计,充分利用和整合技术站铁路运输管理信息系统(TMIS)和办公自动化网络等信息资源,实现统计工作自动化、分析工作网络化和车站作业组织的动态模拟,准确、即时地分析车站运输生产情况,挖掘潜能,为决策提供适时、可靠的依据,适应运输市场的快速变化。  相似文献   
8.
The maritime industry provides an interesting case study of the design and implementation of drug-testing programs in the transportation industry during the 1980s. It is clear that such programs were designed and implemented less because of empirical evidence of safety problems than for political reasons. The results in the maritime industry are indicative of a program that is expensive to operate, intrusive with regard to employee privacy, and which will have little or no impact on safety. Focusing such programs on the issue of impairment rather than on the issue of drug usage per se is likely to improve the outcome of the programs. Although, despite common belief, there is little evidence that drug usage or the “drug problem” in U.S. society as a whole had gotten worse in the preceding years (Schonsheck, 1989, 250–251).  相似文献   
9.
本文首先讲述了ITS中的2种通信技术——专用短程通信(DSRC)和蜂窝数字分组数据网(CDPD)的基本概念、工作原理及系统特点等,然后提出了一种基本这2种通信技术的先进公交系统,并对各个子系统的功能结构进行了描述。  相似文献   
10.
基于模糊熵和多目标规划的公路货运交通枢纽布局模型   总被引:1,自引:0,他引:1  
张华  何波  刘耕 《物流技术》2007,26(7):46-47
针对货运交通枢纽布局问题,首先利用模糊熵获得指标的权重,集结指标值后得到备选交通枢纽的综合评价值,建立一个多目标规划模型来最小化交通成本,最大化建设枢纽的综合评价值,求解后确定货运枢纽的位置、数量、容量等级。  相似文献   
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