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811.
Qinhua Fang Luoping Zhang Huasheng Hong Liyu Zhang Frances Bristow 《Environment, Development and Sustainability》2008,10(1):41-49
Environmental planning at different levels has been called for by environmental departments in China during last years to integrate environment consideration to economic development. Based on the accomplished environmental planning practice in Xiamen China, the paper suggests a general environmental planning process with ecological function zoning as its key steps, at the same time an effective method for ecological function zoning was formulated. The case studies of Dongfu suburban town environmental planning and Xiamen eco-city conceptual planning indicate that scientifically sound results of ecological function zoning can contribute to improving not only the adaptability and acceptability of environmental planning, also the environmental management and the decision-making. The experience shows that the ecological function zoning methods should be applied according to the principles of adaptive management, resource-based and community-based, so that it can integrate science into decision-making process, avoiding both narrow-minded viewpoints of planners and natural resource use conflicts among variety of stakeholders. Problems to be resolved in the future are also pointed out in the ending part. 相似文献
812.
This study examines the relationship between air pollution, social deprivation and health in the city of Leeds, UK under a baseline and three distance-based road user charging (RUC) scenarios set at 2 pence, 10 pence and 20 pence/km. Through application of a series of linked models of traffic, emission and pollutant dispersion, air quality was modelled in response to RUC scenarios. The pollutant modelled were NO(2), PM(10), CO, benzene and 1,3-butadiene, though results of NO(2) are used in this study. The RUC scenarios were compared with the 'base' scenario, all set for the year 2005. The RUC initiatives result in the differences in ambient concentrations of NO(2). The study correlates NO(2) concentrations with derived indices of social deprivation and health. The study concludes that positive but weak relationship exists between air quality and social deprivation, and indicates that deprived population groups are disproportionately exposed to higher NO(2) levels. The relationship between air quality and health status of the population is weak. There is a strong relationship between social deprivation and health status of the population. The study concludes that RUC scenarios result in reducing disparity between affluent and deprived populations. 相似文献
813.
分析了应急监测装备的配置形势,提出了应急监测装备的配置思想和配置原则,剖析了配置的关键点在于实现快速响应功能,准确、快速监测数据获取功能,快速解析、准确判断污染趋势功能,图像和声讯实时双向传输功能,以及安全保障和防护功能. 相似文献
814.
为定量分析海上交通安全风险因素间的影响关系,识别导致海上交通事故的关键因素,分别从单因素、双因素和多因素的角度分析了人、船、环境、管理等风险因素间的耦合关系,运用N-K模型构建了海上交通安全风险耦合度量模型,结合中国海事局、德国联邦海事事故调查局、英国船舶事故调查局和美国国家运输安全委员会等海事调查机构公布的710起海上交通事故,利用所构建的模型计算出不同风险耦合的发生概率和风险值。结果表明:风险耦合因素越多,海上交通事故的发生概率越高;人的因素是引发海上交通事故的重要原因。 相似文献
815.
816.
为提升排土场稳定性,以某露天煤矿排土场为例,结合正交试验和强度折减法,开展排土场稳定性影响因素显著性研究.通过分析资料与野外调研,厘定典型排土场稳定性诱发因素,构建排土场真三维地质模型,反演验证和分析排土场的岩土体参数和变形规律特征,得出排土场边坡内部应力和位移的变化特征以及塑性破坏区分布范围;以真三维网格模型中最危险... 相似文献
817.
环境风会改变排烟窗附近的烟气流向和速度,影响建筑内烟气流动,进而导致建筑自然排烟效率受到影响。采用数值模拟方法,对比研究了排烟窗开启角度和环境风对上、下悬窗阻风能力的影响,分析了不同开窗角度下,悬窗进风量和进风区域随开窗角度和风速的变化规律。结果表明:上、下悬窗相对进风量与开窗角度均成指数关系,但上悬窗阻风能力弱于下悬窗,上悬窗开窗角度大于45°后即失去阻风能力,而下悬窗开窗角度大于75°后才逐渐失去阻风能力,且开窗角度小于30°时,下悬窗至少能比上悬窗多减少50%空气进入室内。上悬窗开窗角度小于56°时,主要进风区域为近窗下侧水平区域;下悬窗开窗角度小于30°时,主要进风区域为窗体两侧及远窗下侧竖直区域,随着开窗角度增大,上、下悬窗主要进风区域均过渡到远窗下侧竖直区域。窗体用于日常通风时建议优选上悬窗。若要用于排烟,则应首选下悬窗,开窗角度15°即可满足阻风要求,若选用上悬窗,开窗角度不宜大于45°。 相似文献
818.
Introduction: Fatal crashes that include at least one fatality of an occupant within 30 days of the crash cause large numbers of injured persons and property losses, especially when a truck is involved. Method: To better understand the underlying effects of truck-driver-related characteristics in fatal crashes, a five-year (from 2012 to 2016) dataset from the Fatality Analysis Reporting System (FARS) was used for analysis. Based on demographic attributes, driving violation behavior, crash histories, and conviction records of truck drivers, a latent class clustering analysis was applied to classify truck drivers into three groups, namely, ‘‘middle-aged and elderly drivers with low risk of driving violations and high historical crash records,” ‘‘drivers with high risk of driving violations and high historical crash records,” and ‘‘middle-aged drivers with no driving violations and conviction records.” Next, equivalent fatalities were used to scale fatal crash severities into three levels. Subsequently, a partial proportional odds (PPO) model for each driver group was developed to identify the risk factors associated with the crash severity. Results' Conclusions: The model estimation results showed that the risk factors, as well as their impacts on different driver groups, were different. Adverse weather conditions, rural areas, curved alignments, tractor-trailer units, heavier weights and various collision manners were significantly associated with the crash severities in all driver groups, whereas driving violation behaviors such as driving under the influence of alcohol or drugs, fatigue, or carelessness were significantly associated with the high-risk group only, and fewer risk factors and minor marginal effects were identified for the low-risk groups. Practical Applications: Corresponding countermeasures for specific truck driver groups are proposed. And drivers with high risk of driving violations and high historical crash records should be more concerned. 相似文献
819.
Problem: The rollover crash is a serious crash type that often causes higher injury severities. Moreover, factors that contribute to the injury severities of rollover crashes may show instabilities in different vehicle types and time periods, which requires further investigations. This study utilizes the rollover crash data in North Carolina from Highway Safety Information System (HSIS) to study the effect instabilities of factors in vehicle type and time periods in rollover crashes. Methods: The injury severities of drivers are estimated using the random parameters logit (RPL) model with heterogeneity in means and variances. Available factors in HSIS have been categorized into three groups, which are drivers, road, and environment, respectively. This study also justifies the segmentations through transferability tests. The effects of identified significant factors are evaluated using marginal effects. Results: Factors such as FWP (farm, wood, and pasture areas), unhealthy physical condition, impaired physical condition, road adverse, and so forth have shown instabilities in marginal effects among vehicle types and time periods. Practical Applications: The finding of this research could provide important references for policy makers and automobile manufactures to help mitigate the injury severity of rollover crashes. 相似文献
820.
Process safety incidents can result in injuries, fatalities, environmental impacts, facility damage, downtime & lost production, as well as impacts on a company's and industry's reputation. This study is focused on an analysis of the most commonly reported contributing factors to process safety incidents in the US chemical manufacturing industry. The database for the study contained 79 incidents from 2010 to 2019, partly investigated by the Chemical Safety Board (CSB). To be included in the study, the CSB archive of incident investigations were parsed to include only incidents which occurred at a company classified as 325 in the North American Industry Classification System (NAICS), assigned to businesses that participate in chemical manufacturing. For each incident, all of the identified contributing factors were catalogued in the database. From this list of identified contributing factors, it was possible to name the ‘top three’ contributing factors. The top three contributing factors cited for the chemical manufacturing industry were found to be: design; preventive maintenance; and safeguards, controls & layers of protection. The relationship between these top contributing factors and the most common OSHA citations was investigated as well. The investigation and citation history for NAICS 325 companies in the Occupational Safety & Health Administration (OSHA) citations database was then analysed to assess whether there was any overlap between the top reported contributing factors to process safety events and the top OSHA citations recorded for the industry. A database consisting of the inspection and citation history for the chemical manufacturing industry identified by NAICS code 325 was assembled for inspections occurring between 2010 and 2020 (August). The analysis of the citation history for the chemical manufacturing industry specifically, identified that the list of the top contributing factors to process safety incidents overlapped with the most common OSHA violations. This finding is relevant to industry stakeholders who are considering how to strategically invest resources for achieving maximum benefit – reducing process safety risk and simultaneously improving OSHA citation history. 相似文献