Does economic growth and energy consumption drive environmental degradation in China’s 31 provinces? New evidence from a spatial econometric perspective

The panel data analysis points to economic and social factors contributing to NO_x, PM_2.5, 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 (NO_x, PM₁₀, VOCs, and PM_2.5) 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.     

An explorative study of corporate travellers’ perception at a German airport

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.     

室内空气污染及防治对策

文章通过对室内空气污染物成因的分析,指出目前室内空气主要污染物为甲醛、苯系物、氨和氡。     

黄石市空气微生物动态变化分析

为了了解黄石市空气微生物动态变化特征,于2004年春、夏、秋、冬选择黄石市有代表性的工业区、居民区、商业交通混合区、长途客运站、市郊地区进行空气微生物监测分析.结果为黄石市不同区域空气菌落数从大到小顺序为：百货大楼十字路口〉步行街〉亚光新村〉新长途客运站〉华新水泥厂〉黄石理工学院主楼广场.空气微生物季节变化为秋季〉春季〉夏季〉冬季.黄石市空气微生物菌落数的高峰出现在商业交通混合区的秋季和春季.     

工作流管理系统的结构与应用

本文介绍了用于企业业务流程管理的工作流的结构和应用 ,详细地说明了各个阶段的功能实现以及工作流引擎等 ,最后讨论了工作流在实际实现中的各种应用。     

制冷剂流量和风量对再循环蒸发器传热性能影响

蒸发器超倍供液系统中的制冷剂有较大流速,增加了液体制冷剂和蒸发管内表面的接触,从而改善换热,增大传热系数,提高蒸发器的效率。本文对再循环蒸发器制冷剂流量和配用风机的风量对蒸发器的净制冷量的影响作了理论计算分析,为合理设计再循环蒸发器提供了理论依据。     

基于灰关联法发动机故障诊断的研究

应用灰关联理论对发动机的故障进行诊断。灰关联分析属非函数型的序列模式,能有效处理杂散数据。通过建立工程机械发动机系统故障树,运用灰关联分析对关联度进行计算及排序,给出各种故障模式发生的可能性排序,从而为处理故障、控制故障的发生以及改进系统的可靠性提供理论依据。     

Hedonic models and air pollution: Twenty-five years and counting

This paper reports a meta analysis of how effectively hedonic property models have detected the influence of air pollution on housing prices. Probit estimates are reported describing how data, model specification, and local property market conditions in cities represented in thirty-seven studies influence the ability of hedonic models to uncover negative, statistically significant relationships between housing prices and air pollution measures.Partial support for this research was provided by the Russell Sage Foundation. Thanks are due David Cordray, Heidi Hartman, and Larry Hedges of the Foundation's Meta-Analysis Panel for constructive comments, to Ray Palmquist for suggestions and assistance in assembling the results from his studies, to Rick Freeman and Tom Tietenberg and two anonymous referees for comments on the research, and to Barbara Scott for constructive editing of earlier drafts of this paper.     

The hidden value of air transportation infrastructure

Air transportation is a key strategic asset in that it provides access to markets and thereby enables the economic development of nations. Thus, in order to maintain their competitiveness in a global economy, countries must invest in air transportation infrastructure to ensure their ability to meet current and future demand for aviation services. The objective of this paper is to develop and illustrate a methodology for evaluating the strategic value of air transportation infrastructure, in particular the benefits associated with the ability to react quickly to changes in the market. The hypothesis is that by recognizing and taking advantage of this strategic value, it may be possible to design better policies for aviation infrastructure delivery.The methodology developed here uses system dynamics to model different strategies for infrastructure delivery. These strategies are defined by three variables: the amount of capacity increase, the time to deliver the capacity and the congestion threshold that triggers the need for capacity delivery. Monte Carlo simulation is used to take into account multiple sources of uncertainty. The model shows that a strategy of capacity delivery based on small increments and short response times can yield more benefits than strategies that consider large capacity increases and long response times. Furthermore, in the specific airport example considered here, it was found that a congestion threshold of 75% should be the trigger for capacity enlargements if strategies based on small capacity increments and 1 or 5 years to increase capacity are considered. The lesson for decision-makers is that congestion delays must be addressed with foresight.     

Health Damage of Air Pollution: An Estimate of a Dose–Response Relationship for the Netherlands

This paper estimates the dose-response relationship between air pollution and the number of work loss days for the Netherlands. The study is based on illness data (work loss days) for the Dutch labour population and average year concentrations of air pollution in 29 districts. The dose-response relationship has been estimated by means of two different techniques: the ordinary least squares method (OLS) and the one-way fixed-effects method (OWFEM), which we consider to be more adequate. In general health effects are much smaller when OWFEM is applied than if OLS is used. With OWFEM a significant relationship is found between sulphate aerosol (SO₄), ammonia (NH₃) and the number of work loss days (WLDs). Particulates (TSP), O₃ and SO₂ have no significant effect on the number of WLDs. These results differ from those obtained in studies in the United States, which indicate that particulates (TSP) and other small particles, ozone (O₃) and to a lesser extent SO₄ and SO₂ significantly influence the number of WLDs.