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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.
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
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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. 相似文献
5.
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。 相似文献
6.
Hedonic models and air pollution: Twenty-five years and counting 总被引:2,自引:1,他引:2
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. 相似文献
7.
Bruno Miller Author Vitae John-Paul Clarke Author Vitae 《Technological Forecasting and Social Change》2007,74(1):18-35
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. 相似文献
8.
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. 相似文献
9.
Knut H. Alfsen Hugo Birkelund Morten Aaserud 《Environmental and Resource Economics》1995,5(2):165-189
Emission of CO2, SO2 and NOx are all closely linked to the burning of fossil fuels. Here we report on simulations done by linking a Sectoral European Energy Model (SEEM), covering energy demand in nine Western European countries, with the emission-transport-deposition model RAINS developed by IIASA. The study analyses emissions of CO2, SO2 and NOx, deposition of sulphur and nitrogen and the extent of areas where the critical load for sulphur is exceeded in year 2000 under four different energy scenarios. Two different sets of future behavioural patterns for the thermal electric power production sector are considered. In one regime, called the plan-efficient regime, the sector is assumed to follow official plans with regard to investment in new capacity. In the other regime, called the cost-efficient regime, the thermal power sector is assumed to behave in a cost minimizing manner. The effects of the proposed EC carbon/energy tax are studied under both regimes, giving rise to altogether four scenarios.In both regimes the effect of the EC tax is to reduce emissions by between 6 and 10 per cent in year 2000 relative to the scenarios without the tax. A change of regime, from the regulated, plan-efficient regime to the market-based, cost-efficient regime, will, by itself, reduce emissions of CO2 and NOx by approximately 3 per cent, while SO2 emissions are reduced by 13 per cent. The EC tax will reduce sulphur deposition by more than 5 per cent in the nine model countries under the plan-efficient regime. A change of regime further reduces the total deposition by 9 per cent. The area where depositions exceed the critical load is reduced by approximately 6 per cent in year 2000 by the tax in both regimes. Changing from the plan-efficient to the cost-efficient regime has a similar impact.Although the emission reductions due to the EC tax may seem modest, they are shown to have a sizeable effect on the technological abatement costs of reaching targets like those prescribed in the Sofia protocol on the stabilisation of NOx emissions, and the Helsinki protocol on SO2 emission reductions. This is part of what can be considered to be secondary benefits of the EC carbon/energy tax. 相似文献
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