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181.
对消防经济学理论与方法研究框架的探讨 总被引:1,自引:0,他引:1
本文分析了国内外消防经济学的研究概况,从宏观和微观两个方面对消防经济学的研究框架、基本理论与方法等进行了全面论述,并对我国消防经济学韵研究及应用前景进行了展望。目的在于为填补我国在该研究领域的空白提供探索性的指导。 相似文献
182.
缺氧-好氧生物脱氮工艺曝气量在线控制策略分析 总被引:4,自引:1,他引:4
曝气控制是生物脱氮工艺重要的控制变最,它决定着整个处理系统的处理效果和运行费用.应用Benchmark-BSM1平台模型对缺氧-好氧生物脱氮工艺几种典型的曝气控制策略进行了研究,结果表明,前馈-反馈曝气量控制最优,其次为反馈控制、恒DO控制和恒曝气量控制.前馈-反馈控制和恒DO控制相比较,出水氨氮浓度大约降低24%,最大出水氨氮浓度降低18%,曝气能耗降低9%,获得了曝气量最优控制方法以及在不同运行条件下应采用的曝气控制策略,为了实现缺氧-好氧生物脱氮工艺硝化反应的最优控制,应同时控制曝气量和好氧区体积. 相似文献
183.
排污权交易定价下的COD和氨氮削减成本分析研究 总被引:1,自引:0,他引:1
调查测算了工业废水COD和氨氮削减成本并进行了分析。总成本中折旧费和日常运行费各占35%和65%;COD和氨氮削减成本为1 287元/t~29 035元/t和2 433元/t~46 560元/t,加权均值为4 936元/t和17 755元/t,二者之比为3.60∶1,90%置信区间为(4 647,8 514)和(13 989,24 617);70%和63.2%的企业以6 837元/t和20 083元/t以内的成本削减了73.7%的COD和42.1%的氨氮。不同企业和行业COD和氨氮削减成本差异明显,以概率分布确定综合成本用于排污权交易定价可能更合理。 相似文献
184.
快速交通对区域中心城市日常可达性影响——以长江三角洲地区为例 总被引:2,自引:0,他引:2
近年来高速公路、高速铁路等快速交通不断发展,城市区域可达性得到大幅提高。基于栅格数据的成本加权距离法,利用平均旅行时间、等时圈以及日常可达性等区域可达性指标,比较分析有无高速公路和有无高速铁路情况下长三角地区中心城市可达性空间格局变化,探索两种快速交通方式对中心城市可达性的影响差异。结果显示:由于高速公路网发育程度较好,对城市区域可达性的影响较为均衡,而高速公路桥能显著缩短两岸旅行时间;高速铁路运行速度更快,但主要沿大城市带呈线状分布,因此对沿线可达性改善明显,尤其是对铁路端点城市;高速铁路较高速公路对城市之间日常可达时间优化效果显著;高速公路和高速铁路对于可达性影响各异,需衔接配合方能大幅提高城市日常可达性,促进区域经济社会公平快速发展 相似文献
185.
全世文 《中国人口.资源与环境》2017,(9):46-55
科学地评估空气质量的经济价值是政府制定空气污染治理政策的必要前提。近年来选择实验方法逐渐兴起,并被研究者广泛应用于环境价值评估。与其他陈述偏好方法相比,选择实验的一个优势是其具有更高的外部效度。选择实验方法在国内的应用研究尚处在起步阶段。本研究分别在2015年和2016年对北京市居民开展了两次基于选择实验方法的网络调查,在调查数据的基础上采用随机参数Logit和广义多元Logit模型分析了北京市居民对空气质量的偏好,并据此估算了空气质量价值。根据2015年样本的估算结果,雾霾天气(PM_(2.5)超标)和沙尘天气(PM_(10)超标)对北京市居民的平均边际价值分别为6.32元/d和2.69元/d;根据2016年样本的估算结果,两个价值分别为7.72元/d和2.81元/d。上述估算结果在两次调查样本中基本稳定,而且,在多种模型设定下都具有较强的稳健性,与近年来的同类研究结果基本一致。以2016年样本的估算结果为基础,2015年北京市雾霾天气和沙尘天气引起的价值损失分别为239.61亿元和45.13亿元,占北京市当年GDP总量的1.04%和0.20%。进一步研究发现,北京市2015年和2016年空气质量改善的价值均低于北京市政府同年用于治理空气污染投入的财政资金总量,说明资金使用效率有待进一步提高;此外,虽然空气质量对高收入居民具有更高的价值,但是,以收入水平为指标设计的累进税率并不比固定税率更优。 相似文献
186.
中国环保产业市场定价策略探索 总被引:6,自引:0,他引:6
本文运用成本定律来分析环保产业的定价策略,提出有利于我国环保产业发展的合理价格机制。 相似文献
187.
188.
The Energy Policy Act of 1992 motivated transit agencies to utilize alternative-fuel transit buses in addition to their popular diesel buses. Transit agencies have planned to add a significant number of alternative-fuel buses to their current transit fleets. This study is to inform policy makers who may allocate public funds for alternative-fuel bus projects to make a smarter decision in this regard. For each of the eight alternative-fuel buses, technologies introduced by the ACT, fuel efficiency, life-cycle cost (LCC) and emission are estimated and compared with the available information for the ultralow-sulfur diesel (ULSD) fuel buses. A case study in the State of Delaware is presented to demonstrate how the proposed approaches can be employed to evaluate the relative importance of the most viable alternative-fuel transit buses according to the predefined set of criteria. The results show that buses propelled by hybrid-diesel engine have the least LCC and emissions and are the most suitable alternative for the ULSD buses in the short- and midterm. 相似文献
189.
Weber R Gaus C Tysklind M Johnston P Forter M Hollert H Heinisch E Holoubek I Lloyd-Smith M Masunaga S Moccarelli P Santillo D Seike N Symons R Torres JP Verta M Varbelow G Vijgen J Watson A Costner P Woelz J Wycisk P Zennegg M 《Environmental science and pollution research international》2008,15(5):363-393
BACKGROUND, AIM AND SCOPE: Once they have been generated, polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and other persistent organic pollutants (POPs) can persist in soils and sediments and in waste repositories for periods extending from decades to centuries. In 1994, the US EPA concluded that contaminated sites and other reservoirs are likely to become the major source of contemporary pollution problems with these substances. With this in mind, this article is the first in a new series in ESPR under the title 'Case Studies on Dioxin and POP Contaminated Sites--Contemporary and Future Relevance and Challenges', which will address this important issue. The series will document various experiences from sites contaminated with PCDD/F and other POPs. This article provides an overview of the content of the articles comprising the series. In addition, it provides a review of the subject in its own right and identifies the key issues arising from dioxin/POP-contaminated sites. Additionally, it highlights the important conclusions that can be drawn from these examples. The key aim of this article and of the series as a whole is to provide a comprehensive overview of the types of PCDD/F contaminated sites that exist as a result of historical activities. It details the various processes whereby these sites became contaminated and attempts to evaluate their contemporary relevance as sources of PCDD/Fs and other POPs. It also details the various strategies used to assess these historical legacies of contamination and the concepts developed, or which are under development, to effect their remediation. MAIN FEATURES: Special sessions on 'Contaminated sites--Cases, remediation, risk and policy' were held at the DIOXIN conferences in 2006 and 2007, and this theme will be continued at DIOXIN 2008 to be held in Birmingham. Selected cases from the approximately 70 contributions made to these sessions, together with some additional invited case studies are outlined together with the key issues they raise. By evaluating these cases and adding details of experiences published in the current literature, an overview will be given of the different features and challenges of dioxin and POP-contaminated sites. RESULTS: This article provides a systematic categorisation of types of PCDD/F and POP-contaminated sites. These are categorised according to the chemical or manufacturing process, which generated the PCDD/Fs or POPs and also includes the use and disposal aspects of the product life cycle in question. The highest historical PCDD/F and dioxin-like polychlorinated biphenyl (PCB) contamination burdens have arisen as a result of the production of chlorine and of chlorinated organic chemicals. In particular, the production of chlorinated pesticides, PCBs and the related contaminated waste streams are identified being responsible for historical releases of toxic equivalents (TEQs) at a scale of many tonnes. Along with such releases, major PCDD/F contaminated sites have been created through the application or improper disposal of contaminated pesticides, PCBs and other organochlorine chemicals, as well through the recycling of wastes and their attempted destruction. In some extreme examples, PCDD/F contaminated sites have also resulted from thermal processes such as waste incinerators, secondary metal industries or from the recycling or deposition of specific waste (e.g. electronic waste or car shredder wastes), which often contain chlorinated or brominated organic chemicals. The examples of PCDD/F and dioxin-like PCB contamination of fish in European rivers or the impact of contaminated sites upon fishing grounds and upon other food resources demonstrate the relevance of these historical problems to current and future human generations. Many of the recent food contamination problems that have emerged in Europe and elsewhere demonstrate how PCDD/F and dioxin like PCBs from historical sources can directly contaminate human and animal feedstuffs and indeed highlight their considerable contemporary relevance in this respect. Accordingly, some key experiences and lessons learnt regarding the production, use, disposal and remediation of POPs from the contaminated sites are summarised. DISCUSSION: An important criterion for evaluating the significance and risks of PCDD/Fs and other POPs at contaminated sites is their present or future potential for mobility. This, in turn, determines to a large degree their propensity for off-site transport and environmental accessibility. The detailed evaluation of contaminated site cases reveals different site-specific factors, which influence the varied pathways through which poor water-soluble POPs can be mobilised. Co-contaminants with greater water solubility are also typically present at such sites. Hence, pumping of groundwater (pump and treat) is often required in addition to attempting to physically secure a site. At an increasing number of contaminated sites, securing measures are failing after relatively short time spans compared to the time horizon, which applies to persistent organic pollutant contamination. Due to the immense costs and challenges associated with remediation of contaminated sites 'monitored natural attenuation' is increasingly gaining purchase as a conceptual remediation approach. However, these concepts may well prove limited in their practical application to contaminated sites containing persistent organic pollutants and other key pollutants like heavy metals. CONCLUSIONS: It is inevitable, therefore, that dioxin/POP-contaminated sites will remain of contemporary and future relevance. They will continue to represent an environmental issue for future generations to address. The securing and/or remediation of dioxin/POP-contaminated sites is very costly, generally in the order of tens or hundreds of millions of dollars. Secured landfills and secured production sites need to be considered as constructions not made for 'eternity' but built for a finite time scale. Accordingly, they will need to be controlled, supervised and potentially repaired/renewed. Furthermore, the leachates and groundwater impacted by these sites will require ongoing monitoring and potential further remediation. These activities result in high maintenance costs, which are accrued for decades or centuries and should, therefore, be compared to the fully sustainable option of complete remediation. The contaminated site case studies highlight that, while extensive policies and established funds for remediation exist in most of the industrialised western countries, even these relatively well-regulated and wealthy countries face significant challenges in the implementation of a remediation strategy. This highlights the fact that ultimately only the prevention of contaminated sites represents a sustainable solution for the future and that the Polluter Pays Principle needs to be applied in a comprehensive way to current problems and those which may emerge in the future. RECOMMENDATIONS AND PERSPECTIVES: With the continuing shift of industrial activities in developing and transition economies, which often have poor regulation (and weak self-regulation of industries), additional global challenges regarding POPs and other contaminated sites may be expected. In this respect, a comprehensive application of the "polluter pays principle" in these countries will also be a key to facilitate the clean-up of contaminated areas and the prevention of future contaminated sites. The threats and challenges of contaminated sites and the high costs of securing/remediating the problems highlight the need for a comprehensive approach based upon integrated pollution prevention and control. If applied to all polluting (and potentially polluting) industrial sectors around the globe, such an approach will prove to be both the cheapest and most sustainable way to underpin the development of industries in developing and transition economies. 相似文献
190.
基于空间距离和时间成本的中小文化旅游城市可达性研究 总被引:4,自引:0,他引:4
在区域旅游发展中,中小文化旅游城市是其重要内容之一。除旅游景点本身的吸引力之外,旅游目的地的可达性及旅游景点基础设施的完善是其旅游发展的重要内容,因此中小文化旅游城市的可达性研究具有重要意义。基于GIS软件,论文从空间距离和时间成本角度对全国34个中小文化旅游城市的可达性进行研究。结果表明:我国中小文化旅游城市的可达性表现出非均衡的空间分布特征,其3 h可达服务范围(即游客市场)并未覆盖全国。其中,东北地区、华南地区、内蒙古高原、青藏高原等地区因中小文化旅游城市分布较少而出现可达服务范围的空白区域,而长江三角洲、成渝、鲁西南和海峡西岸等地区中小文化旅游城市的可达服务范围已绵延成片,具有较大的区域旅游合作潜力。此外,通过对中小文化旅游城市的旅游收入、旅游人数与可达范围内社会经济属性进行相关性分析,发现旅游收入与1 h可达范围内的GDP相关性最高,而旅游人数与50 km范围内的GDP相关性最高。 相似文献