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291.
We examine the choice of policy instruments (price, quantity or a mix of the two) when two pollutants are regulated and firms' abatement costs are private information. Whether abatement efforts are complements or substitutes is key determining the choice of policies. When pollutants are complements, a mixed policy instrument with a tax on one pollutant and a quota on another is sometimes preferable even if the pollutants are identical in terms of benefits and costs of abatement. Yet, if they are substitutes, the mixed policy is dominated by taxes or quotas. 相似文献
292.
伴随着中国石油企业走出去的步伐不断加快,海外油气项目的规模迅速扩大,相较于国内而言,海外油气项目面临的环境更加复杂,HSE管理难度更大。探索一种科学、高效并且符合现代化管理要求的先进管理手段,与企业的HSE管理有机融合,从而确保企业HSE管理体系良好运行,对于企业具有重要意义。中国某石油企业海外项目(A公司)在此方面进行了大量、有益的实践,其将自身的信息管理系统与HSE体系有机融合,从而实现了HSE管理的信息化。选取A公司的事故预防应急系统作重点介绍,将A公司的事故预防管理与传统事故预防管理进行对比,同时将A公司的应急管理与传统应急管理进行对比,最后提出了针对HSE管理信息化的思考,以期对石油企业海外项目的HSE管理提供帮助。 相似文献
293.
This paper examines changes in disaster response and relief efforts and recent web‐based geospatial technological developments through an evaluation of the experiences of the Center for Geographic Analysis, Harvard University, of the Sichuan (2008) and Haiti (2010) earthquake responses. This paper outlines how conventional GIS (geographic information systems) disaster responses by governmental agencies and relief response organisations and the means for geospatial data‐sharing have been transformed into a more dynamic, more transparent, and decentralised form with a wide participation. It begins by reviewing briefly at historical changes in the employment of geospatial technologies in major devastating disasters, including the Sichuan and Haiti earthquakes (case studies for our geospatial portal project). It goes on to assess changes in the available dataset type and in geospatial disaster responders, as well as the impact of geospatial technological changes on disaster relief effort. Finally, the paper discusses lessons learned from recent responses and offers some thoughts for future development. 相似文献
294.
295.
I analyze the pricing and investment behavior of a firm that signals the environmental attributes of its production technology through its price to uninformed environmentally conscious consumers. I then analyze the effect of change in environmental regulation on the signaling outcome and the firm's ex ante incentive to invest in cleaner technology. When regulation is weak, a firm signals cleaner technology through higher price; in this case, the firm earns lower profit when it has cleaner technology and thus, has no incentive to invest in cleaner technology. The price charged by the clean firm declines sharply beyond a critical level of regulation. When regulation is sufficiently stringent, the firm with cleaner technology charges lower price but earns higher signaling profit, and ex ante the firm has positive incentive to invest in cleaner technology. With weak regulation, the incentive of the firm to directly disclose its environmental performance rather than signal it through price is increasing in the level of regulation; the opposite holds when regulation is sufficiently stringent. 相似文献
296.
This paper presents a simple system for efficient regulation under asymmetric information. Each firm's income is controlled by a tax that depends on the firm's own output and on a parameter construed as a share permit. These “shares of total expected output” lower a firm's tax burden and are acquired in a competitive market. By employing this scheme, the planner only requires knowledge of marginal damage to induce the first-best outcome. Relative to a traditional cap-and-trade approach the system increases expected social welfare. 相似文献
297.
东北典型黑土区坡沟侵蚀耦合关系 总被引:7,自引:3,他引:4
东北黑土区是中国重要的商品粮基地,但是严重的水土流失给其粮食产量带来了严峻考验。论文在遥感和GIS支持下,选择黑龙江省乌裕尔河和讷谟尔河两流域包含的东北典型黑土区作为研究区,以USLE模型和SPOT 5影像为基础,分别获取了2005年研究区的坡面侵蚀量和侵蚀沟分布数据,据此分析了典型黑土区坡面侵蚀和沟蚀之间在不同等级、 坡度、 坡向等方面的耦合关系。研究发现微度侵蚀和轻度侵蚀是坡面侵蚀主要区域,沟蚀发展程度比较剧烈;坡度小于5°时,坡度是沟蚀产生的制约因素,当大于5°时,坡度已经不是侵蚀沟形成过程中的主要控制因素;阳坡坡面侵蚀量高于阴坡的坡面侵蚀量,坡向在东北典型黑土区不是影响沟蚀发育的首要因子;侵蚀强度在2 500 t/(km2·a)以下的地区,随着坡面侵蚀量的增大侵蚀沟密度增大,而当大于2 500 t/(km2·a)以后,侵蚀沟密度比较稳定。 相似文献
298.
分析了数据管理系统在生态环境领域的应用现状,以及页岩气开发生态环境数据的特性和管理需求,提出了基于地理信息系统和关系型数据库有效集成的数据管理系统框架,实现对页岩气开发区域水环境、土壤环境、环境空气及污染源负荷在时间和空间尺度的分析与评价,指出大数据、物联网技术的运用是系统发展的重要方向. 相似文献
299.
Special needs hurricane shelters and the ageing population: development of a methodology and a case study application
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Mark W. Horner Eren Erman Ozguven Jean Michael Marcelin Ayberk Kocatepe 《Disasters》2018,42(1):169-186
Recent experience of hurricanes, particularly in the southeast United States, has heightened awareness of the multifaceted nature of and the challenges to effective disaster relief planning. One key element of this planning is providing adequate shelter at secure locations for people who evacuate. Some of these individuals will have ‘special needs’, yet there is little research on the relationship with shelter space. This study designed a geographic information systems‐based network optimisation methodology for the siting of special needs hurricane relief shelters, with a focus on the transportation component. It sought to find new locations for shelters that maximise accessibility by vulnerable populations, given capacity constraints, concentrating on the ageing population. The framework was implemented in a medium‐sized metropolitan statistical area in the state of Florida where data suggest a possible deficit in special needs shelter space. The study analysed options for increasing special needs shelter capacity, while considering potential uncertainties in transportation network availability. 相似文献
300.
为了对重大毒气泄漏事故的后果影响及相关疏散区域进行分析,构建基于GIS的重大毒气泄漏事故区域疏散分析系统,对区域疏散分析业务流程和数据流程进行分析,对系统总体结构和数据结构进行设计,并结合具体案例,进行扩散模拟,对事故影响区域以及区域疏散效果进行分析,研究结果表明:混合通知方式下的疏散效率最高,毒气泄漏事故发生后应尽早通知周边居民疏散。 相似文献