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11.
嘉兴市不同区域空气微生物污染状况调查   总被引:1,自引:0,他引:1  
了解嘉兴市不同区域空气微生物污染状况,随机选择嘉兴市城区、城郊结合部和郊区农村三个检测点进行10天的空气采样检测.结果显示空气微生物污染程度以农村为重,其次是城区和城郊结合部.检出污染的细菌以革兰阳性球菌和芽孢杆菌为主,马丁霉菌和耐高渗透压霉菌均以青霉属为优势菌.嘉兴市(尤其是郊区农村)空气微生物污染严重,应引起有关部门关注.  相似文献   
12.
为了化解城市地铁快速建设所带来的车站运营安全风险,为提高我国地铁车站运营管理水平提供参考,论文以青岛地铁车站运营安全管理模式为研究对象,探讨了体系的搭建、措施的落实、结果的检查、问题的改善等环节的科学管理机制。  相似文献   
13.
站场咽喉改造需在不影响铁路运营的前提下在封锁点内完成。如何安全、高效、可行地完成施工任务,关键在于制定详细可行的方案,而施工组织是决定方案是否可行的关键。因此,论文结合哈尔滨站咽喉区组合道岔的施工情况,对施工组织设计及施工技术方案进行了论述。  相似文献   
14.
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   
15.
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   
16.
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   
17.
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   
18.
江苏和甘肃经济发展与大气环境保护状况比较分析   总被引:4,自引:0,他引:4  
江苏是我国东部经济发达地区省份 ,甘肃是西部欠发达省份 ,两省具有不同的经济增长和环境保护特征 ,对其进行比较研究 ,可发现东部与西部地区各自的比较优势 ,为双方的协作互补和相互借鉴探索切合点。本文对两省工业废气排放总量、单位GDP工业废气排放量、工业SO2、工业烟尘和工业粉尘的排放量与去除量、工业废气污染治理投资、工业废气排放重点行业等指标进行了重点定量比较分析 ,得出了相应结论 ,提出了相应措施  相似文献   
19.
通过考察中国航空货运,建立航空顾客价值的决定因素与动态性理论模型,运用结构方程方法对其检验,结果表明:时间因素和便捷性因素是影响货运顾客价值的核心要素,价格因素已退之其次,而且来自竞争者、服务商、顾客、宏观环境的变化都对顾客价值动态性有显著影响。  相似文献   
20.
对物流园区加油站静电火灾的预防问题,从静电产生的原因和着火条件,静电火灾的一般规律,人体静电的危害及预防,静电火灾的预防对策与措施进行了研究  相似文献   
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