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821.
The Process Safety Management (PSM) systems at the operating facilities in the Oil & Gas and in Chemical manufacturing industries have matured over the years and have become, at most facilities, very robust and sophisticated. These programs are administrated by Process Safety (PS) teams at both the corporate business units and plant levels and have been effective in reducing the number and severity of PS events across the industries over the past 25 years or so. Incidents however are occurring at a regular interval and in recent times several noteworthy PS events have occurred in the United States which have brought into question the effectiveness of the PSM programs at play. These facilities have been applying their PSM programs with the expectation that the number and severity of PS events would decrease over time. The expected result has not been realized, especially in context to those facilities that have undergone the recent incidents. Current paper reviews a few publicly available PS performance reports of Oil & Gas and Chemical manufacturing industries. The authors identified a few factors at play that have led to these PS events based on their experience, literature review, and incident investigation reports. Most of the factors are intertwined with multiple PSM elements and it requires a holistic approach to address them. Each of the factors is described and the path forward is proposed to improve the effectiveness of PSM programs. 相似文献
822.
基于分类交通冲突与微观仿真分析的城市交叉口安全诊断及改善 总被引:2,自引:1,他引:1
鉴于传统的城市交叉口交通冲突整体评价方法不能深入地分析和解决交叉口内部的交通安全问题,依据流量和相位时长关系确定分类交通冲突评价系数,计算出不同相位阶段中不同交通冲突类型(机-机、机-非、机-人)的交通冲突率和分类综合交通冲突率,从而比较和诊断交叉口内部危险性高的交通冲突类型及所在相位,并应用VISSIM仿真软件评估相应交通安全改善措施对路口交通效率的影响。以北京市光彩北路路口为对象进行实验分析,其结果表明,分类交通冲突技术与微观交通仿真分析的充分结合,可提高城市交叉口安全诊断的准确性及相应改善措施的有效性。 相似文献
823.
Bio-economic evaluation of implementing trawl fishing gear with different selectivity 总被引:1,自引:0,他引:1
Lone Grnbk Kronbak J. Rasmus Nielsen Ole A. Jrgensen Niels Vestergaard 《Journal of environmental management》2009,90(11):3665-3674
The paper develops a biological-economic evaluation tool to analyse the consequences for trawl fishers of implementing more selective fishing technologies. This is done by merging a dynamic biological population model and an economic cost–benefit evaluation framework to describe the consequences for the fish stocks, fishermen and society. The bio-economic evaluation is applied to the case of the Danish trawl fishery in Kattegat and Skagerrak, which experiences a high level of discards and bycatches of several species. Four different kinds of selectivity scenarios are evaluated in comparison with a baseline. The results from the evaluation are indicators for the consequences on ecological and economic levels. The results show that implementation of different selective fishing gear in the Kattegat and Skagerrak mixed trawl fisheries generally implies a trade off over time between rebuilding the stocks and economic loss. Moreover, the analysis shows that implementation of more selective gear is not always beneficial. 相似文献
824.
Cost/Benefit Considerations for Recent Saltcedar Control,Middle Pecos River,New Mexico 总被引:2,自引:1,他引:1
Major benefits were weighed against major costs associated with recent saltcedar control efforts along the Middle Pecos River,
New Mexico. The area of study was restricted to both sides of the channel and excluded tributaries along the 370 km between
Sumner and Brantley dams. Direct costs (helicopter spraying, dead tree removal, and revegetation) within the study area were
estimated to be $2.2 million but possibly rising to $6.4 million with the adoption of an aggressive revegetation program.
Indirect costs associated with increased potential for erosion and reservoir sedimentation would raise the costs due to increased
evaporation from more extensive shallows in the Pecos River as it enters Brantley Reservoir. Actions such as dredging are
unlikely given the conservative amount of sediment calculated (about 1% of the reservoir pool). The potential for water salvage
was identified as the only tangible benefit likely to be realized under the current control strategy. Estimates of evapotranspiration
(ET) using Landsat TM data allowed estimation of potential water salvage as the difference in ET before and after treatment,
an amount totaling 7.41 million m3 (6010 acre-ft) per year. Previous saltcedar control efforts of roughly the same magnitude found that salvaged ET recharged
groundwater and no additional flows were realized within the river. Thus, the value of this recharge is probably less than
the lowest value quoted for actual in-channel flow, and estimated to be < $63,000 per year. Though couched in terms of costs
and benefits, this paper is focused on what can be considered the key trade-off under a complete eradication strategy: water
salvage vs. erosion and sedimentation. It differs from previous efforts by focusing on evaluating the impacts of actual control
efforts within a specific system. Total costs (direct plus potential indirect) far outweighed benefits in this simple comparison
and are expected to be ongoing. Problems induced by saltcedar control may permanently reduce reservoir capacity and increase
reservoir evaporation rates, which could further deplete supplies on this water short system. These potential negative consequences
highlight that such costs and benefits need to be considered before initiating extensive saltcedar control programs on river
systems of the western United States. 相似文献
825.
Water Quality Improvement Policies: Lessons Learned from the Implementation of Proposition O in Los Angeles,California 总被引:1,自引:0,他引:1
This article evaluates the implementation of Proposition O, a stormwater cleanup measure, in Los Angeles, California. The
measure was intended to create new funding to help the city comply with the Total Maximum Daily Load requirements under the
federal Clean Water Act. Funding water quality objectives through a bond measure was necessary because the city had insufficient
revenues to deploy new projects in its budget. The bond initiative required a supermajority vote (two-thirds of the voters),
hence the public had to be convinced that such funding both was necessary and would be effective. The bond act language included
project solicitation from the public, as well as multiple benefit objectives. Accordingly, nonprofit organizations mobilized
to present projects that included creating new parks, using schoolyards for flood control and groundwater recharge, and replacing
parking lots with permeable surfaces, among others. Yet few, if any, of these projects were retained for funding, as the city
itself also had a list of priorities and higher technical expertise in justifying them as delivering water quality improvements.
Our case study of the implementation of Proposition O points to the potentially different priorities for the renovation of
urban infrastructure that are held by nonprofit organizations and city agencies and the importance of structuring public processes
clearly so that there are no misimpressions about funding and implementation responsibilities that can lead to disillusionment
with government, especially under conditions of fiscal constraints. 相似文献
826.
Robyn Robertson Author Vitae Ward Vanlaar Author Vitae Herb Simpson Author Vitae 《Journal of Safety Research》2009,40(1):25-31
Introduction
This article summarizes the main findings from a study designed to examine the legal process in Canada as it applies to alcohol-impaired driving from the point of view of Crown prosecutors and defense counsel, and to identify evidentiary or procedural factors that may impact the legal process, the rights of the accused, and interactions of all parts in the legal process.Method
The data in this study were collected by means of a survey that was mailed out to the population of Crown prosecutors and defense counsel in Canada. In total, 765 prosecutors and 270 defense lawyers or an estimated 33% of all Canadian prosecutors and 15% of defense lawyers completed and returned the questionnaire. The "systems improvement" paradigm was used to interpret the findings and draw conclusions. Such an approach acknowledges the importance of the context in which countermeasures are implemented and delivered and the structures or entities used to deliver countermeasures to a designated target group.Results
Results on type of charges and breath alcohol concentration, caseload, case outcomes, case preparation time, conviction rate at trial and overall conviction rate, reasons for acquittals and time to resolve cases are described.Discussion
The findings from this national survey suggest that there are important challenges within the criminal justice system that impede the effective and efficient processing of impaired driving cases. Some of these challenges occur as a function of practices and policies, while others occur as a function of legislation.Impact on industry
This study illustrates that a "system improvements" approach that acknowledges the importance of all elements of the criminal justice system and the interaction between those elements, can be beneficial in overcoming the alcohol-impaired driving problem. 相似文献827.
随着经济发展,审计工作将从以财务审计为主导的传统审计,逐渐向以绩效审计为主导的现代审计过渡,在关注经济效益的同时,也更加关注生态效益.作为绩效审计的分支--环境绩效审计也将引起关注.首先对绩效审计、环境绩效审计的含义、目标、特点等作一介绍,然后分析了这2种审计的关系,最后就如何开展环境绩效审计进行了初步探讨. 相似文献
828.
829.
Recycling contaminated soil as alternative raw material in cement facilities: Life cycle assessment 总被引:1,自引:0,他引:1
Volcanic soil can be used to remove metals from wastewaters. Once used, it is disposed in landfills. The utilization of this material in the cement industry as an alternative raw material was evaluated using life cycle assessment (LCA) methodology. This possibility has been studied from an environmental point of view in a Chilean cement facility, representative of the current operation state of art, including both technical and economic analysis. Two scenarios were compared: Scenario 1, which corresponds to the existing cement production process, and Scenario 2, which represents cement production using spent volcanic soil. With the exception of the categories of carcinogens (C) and minerals (M), the comparative results are favourable to Scenario 2, specially regarding to the category of ecotoxicity (E), mainly due to the avoided landfilling emissions of the volcanic soil. When considering the damage assessment, damage to human health (HH), ecosystem quality (EQ) and resources (R) are lower in Scenario 2. In addition, sensitivity analyses were performed to study the influence of particular parameters (i.e., transport of spent volcanic soil, CO2 emissions from the clinkerization process and heavy metals leaching from the spent volcanic soil) on the results of the assessment. The use of alternative raw materials (in this case, spent volcanic soil), which present the advantage to be wastes from other technical systems, appear to allow the development of cement production in a more sustainable way, slightly improving the economy of the process. The spent volcanic soil can be treated with zero cost for the wastewater treatment plant with savings of 0.23€ for each tonne of clinker production. Establishing a sound management way for the spent volcanic soil could foment its possible use as mineral adsorbent in industrial wastewater treatment facilities. 相似文献
830.
浅论经济、社会与环境三效益的矛盾与统一 总被引:1,自引:0,他引:1
阐述了经济效益、社会效益与环境效益之间的相互对立统一的辨证关系,从概念和内涵对其矛盾与统一进行了分析,从其相互关系及综合评价中说明了存在的矛盾问题及解决的方法,只有运用可持续发展的理论改变传统的发展观、自然观,人类就一定能够与环境和谐共存,达到经济、社会与环境三效益的结合与统一。 相似文献