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131.
This article investigates potential differences in risk perception between experts (loss-prevention managers in the U.K. oil and gas production industry) and nonexperts (managers and students). Extant research on expert versus nonexpert perceptions of risk is reviewed, followed by the present study concerning risk perceptions of seven pen-picture scenarios involving the occurrence of hazardous events in the U.K. oil and gas production industry. In contrast to many of the earlier studies of expert versus nonexpert perceptions of risk, the present analysis concludes that experts did not judge the overall riskiness of the portrayed hazardous events as less risky than the nonexperts. Nevertheless, the experts believe more strongly than our nonexperts that the risks portrayed in the scenarios pose little threat to future generations, are more precisely known, and are relatively controllable. Use of multiple regression analysis to help uncover the basis of overall riskiness assessments for expert and lay respondents was inconclusive, however. Finally, little evidence was found that nonexperts were any more heterogeneous in their risk perceptions than experts. It may be that the nature of the risks assessed in the present study may account for the general lack of clear expert versus nonexpert differences in overall perceptions of the riskiness of hazardous events in the North Sea. Earlier findings of strong expert versus nonexpert differences in risk perception assessed hazards of major public concern. It is inferred that using such extreme hazards may have resulted in an exaggerated view of differences in expert versus public (nonexpert) perception of risk.  相似文献   
132.
在分析气藏压力变化后气井储层渗流参数和流体参数变化特征的基础上,利用实例井测试和实验分析数据,分别提出了不同类型气井产能变化规律,对其递减规律进行了理论预测,并使用矿场数据进行了定量分析,且对比了常规研究方法,着重于对产能方程系数的变化分析,尝试利用先前获取的稳定试井资料分析储层压力大幅下降后的产能动态。结果表明,常规气井产能变化主要受流体状态参数的影响;储层压力低于露点压力后,凝析气井组分变化和凝析液析出控制着气井产能的递减;变形储层开采期间储层渗流参数的变化会加快气井产能的递减速度,用修正的勘探阶段测试数据来预测产能递减能够满足工程需要。研究可为优化不同类型气井工作制度提供参考。  相似文献   
133.
通过构建新古典闭合框架下的静态可计算一般均衡(Computable General Equilibrium,CGE)模型,模拟天然气开采业取消政府管制对经济增长、居民福利以及产业绩效的影响.模拟结果显示:无论是在短期内还是长期内取消政府管制不仅能够拉动GDP增长、增加居民收入、改善居民福利,还能够有效降低天然气开采业部门的生产成本、提高生产效率、增加天然气的产量、促进天然气的最终消费.因此,应该逐渐打破政府对天然气开采业的行政垄断,降低政府对市场的不合理干预,逐步建立自由竞争的市场.  相似文献   
134.
燃气涡轮工作转速受进油量、进气量和试验装置特性等多种因素的影响,由于这些因素之间有很强的交叉耦合,很难建立精确的数学模型,因此按经典控制理论很难对燃气涡轮的转速进行控制。针对燃气涡轮系统的转速控制问题,文中提出了一种实用的自寻优FUZZYPI模糊控制方案。利用模糊推理合成规则,得出了模糊控制结果,并用于实际系统控制,获得了成功。  相似文献   
135.
油气管道的保护,不仅关联国家能源安全,而且涉及民众的生命财产安全,是公共安全领域的重要课题之一。欲使油气管道的安全获得切实保护,有关立法必须准确定性油气管道的法律属性,并以此为基础合理配置油气管道安全保护中各方主体的法律权利(或权力)、义务和责任,尤其应当根据油气管道安全事故中的复合侵权情形,建立和完善相应的损害赔偿机制和责任追究机制。  相似文献   
136.
设计、制作了一台可测试气体滑脱因子b及岩芯克氏渗透率K的测试装置,其测试原理基于一种测定岩芯气测渗透率Kg的新方法。利用这种方法,此装置可在一次压力下降过程中记录下多个压力、时间点,从而计算出多个Kg值,然后经最小二乘拟合得出b和K。对测试装置作的重复性测试表明该装置是稳定、可靠的。  相似文献   
137.
Fine particle (PM(2.5)) emissions from traffic have been associated with premature mortality. The current work compares PM(2.5)-induced mortality in alternative public bus transportation strategies as being considered by the Helsinki Metropolitan Area Council, Finland. The current bus fleet and transportation volume is compared to four alternative hypothetical bus fleet strategies for the year 2020: (1) the current bus fleet for 2020 traffic volume, (2) modern diesel buses without particle traps, (3) diesel buses with particle traps, and (4) buses using natural gas engines. The average population PM(2.5) exposure level attributable to the bus emissions was determined for the 1996-1997 situation using PM(2.5) exposure measurements including elemental composition from the EXPOLIS-Helsinki study and similar element-based source apportionment of ambient PM(2.5) concentrations observed in the ULTRA study. Average population exposure to particles originating from the bus traffic in the year 2020 is assumed to be proportional to the bus emissions in each strategy. Associated mortality was calculated using dose-response relationships from two large cohort studies on PM(2.5) mortality from the United States. Estimated number of deaths per year (90% confidence intervals in parenthesis) associated with primary PM(2.5) emissions from buses in Helsinki Metropolitan Area in 2020 were 18 (0-55), 9 (0-27), 4 (0-14), and 3 (0-8) for the strategies 1-4, respectively. The relative differences in the associated mortalities for the alternative strategies are substantial, but the number of deaths in the lowest alternative, the gas buses, is only marginally lower than what would be achieved by diesel engines equipped with particle trap technology. The dose-response relationship and the emission factors were identified as the main sources of uncertainty in the model.  相似文献   
138.
张华  张荣 《中国管理科学》2021,29(3):188-198
鉴于出口国时常出现天然气出口供应安全问题,进口国因基础设施滞后引发的天然气供需矛盾,考虑出口供应安全、基础设施与需求量三者之间的相互影响,文章构建了进出口两国之间的动态博弈模型。运用最优控制等理论,求得了双方的均衡策略及效用。结果表明,天然气出口价格越高,使得进口国的天然气销售价格越高及其对基础设施投入越少;出口国为保障出口供应安全付出的努力与天然气出口价格之间呈倒“U”型关系;与天然气寡头竞争市场相比,出口垄断市场的天然气出口价格、出口供应安全、基础设施存量以及出口国效用更高,进口国效用更低;在寡头竞争市场,与合作方式相比,两国在议价下的天然气出口价格、出口供应安全、基础设施存量以及出口国效用更高,进口国效用更低。  相似文献   
139.
This paper reports on an investigation into strategic project management in the UK upstream oil and gas sector. The management process is represented by a set of elements which covers context, content and output and are balanced across financial, internal business, external environment, and learning and innovation perspectives. The paper uncovers elements that appear to explain successful project management and compares these with the elements to which managers pay greatest attention. There appears to be a mismatch between those elements which are associated with success and those receiving significant management attention.  相似文献   
140.
本文通过对教学统计数据的分析和总结,说明三态英语系统教学理论及其教学法的合理性和必要性,以及在当今大学英语教学中所具有的综合性教学运用价值.  相似文献   
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