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1.
沈国庆  郑东  王彦碧 《环境技术》2020,38(4):112-118
磁浮列车正常行进过程中对外部环境的电磁辐射安全性近年来受到各科技强国的广泛重视。本文采用多线传输线MTL方法,对磁浮列车电磁辐射场进行了电磁建模与仿真分析,并基于IEEE-Std-C95.1-2005、IEEEStd-C95.6-2002和ICNIP-2010以及GB8702-2014,标准,采用传感器法和接收天线法,现场测试验证了磁浮列车在不同运行状态下的电磁辐射场,开展电磁环境评估工作。研究表明:50~110 kHz,磁浮列车12 m处的辐射磁场呈周期性结构分布,仿真的最大值为69.4 dBuA/m;1~120 kHz频段内,磁浮列车的辐射磁场测量值小于90 mA/m;在9 kHz~18 GHz频段内,磁浮列车的辐射电场均小于110 dBuV/m(0.316 V/m),磁浮列车对外电磁辐射量值比相关国际标准限值至少低30 dB。本论文的研究工作可为我国新型高速磁浮列车电磁安全性研究奠定基础。  相似文献   

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环境信息能力建设评估研究   总被引:1,自引:0,他引:1  
环境信息能力建设评估可发挥导向作用,促进我国环境信息能力建设长效可持续发展。本文从环境信息能力建设评估体系和评估模型两方面对环境信息能力建设评估做了透彻的分析,并为环境信息能力建设评估体系的应用提出了相关建议,为国内开展环境信息能力建设评估指明了方向。  相似文献   

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寿命评估是可靠性研究中的重要分支,如今主流的寿命评估方法主要集中在单设备单部件级,随着科技的发展,装备逐渐向大型化、智能化和复杂化的方向发展,如何评估复杂装备的系统寿命成为一个待解难题。本文应用具体案例,基于层次结构模型并结合相似产品分析法对系统的寿命评估进行了研究和探讨。  相似文献   

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采用澳大利亚源流域水量水质模型模拟东山小流域内2001-2010年9种不同土地利用类型产生的降雨径流及总氮和总磷的污染负荷,模拟结果为:流域内多年平均径流量为6 150万m3/a,总氮输出负荷为270 t/a,总磷负荷为22 t/a。模拟结果表明:水产养殖塘和高地茶果树是东山地区主要的营养物来源。通过三个情景方案的模拟,说明当地环境管理方案可以有效地削减入湖的营养负荷,其中第二个情景方案的削减量最大,总氮和总磷负荷分别削减了18%和25%。  相似文献   

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科学划分控制单元是实现流域水环境精准、高效管理的重要基础。为满足新时期中国流域系统治理和“三水”统筹的新要求、新任务,设计建立了一种新的控制单元划分技术方法,将中国重点流域划分为3442个断面控制单元和822个流域控制单元。基于控制单元划分成果,进一步构建了包含流域—流域控制单元—断面控制单元—控制断面—水功能区5个层级逐步细化的流域空间管控体系。实际案例分析与论证表明,新的流域空间管控体系能有效促进流域水环境管理各项措施落地,可进一步推动流域治理科学化、精细化、差异化,并为“三水”统筹提供决策支持。  相似文献   

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《"十三五"全国环境保护法规和环境经济政策建设规划》(以下简称《规划》)绘制了"十三五"时期我国环境保护法规和环境经济政策的创新与改革蓝图。"十三五"以来,《规划》实施推动了环境经济政策在生态文明建设生态环境保护工作中的地位快速上升,在筹集环保资金、调控环境行为、激励企业减排等方面发挥了重要作用。为了更好推进环境经济政策改革与创新,本研究采用逻辑框架法对《规划》中期实施进展进行了系统评价,结果表明:在28项《规划》任务中,绿色信贷、环境信息披露制度、环境污染强制责任险等13项任务进展良好,生态环境损害赔偿制度等11项任务进展较好;环境信用建设"入法"等4项规划任务进展较小或者进展一般。研究表明《规划》总体实施顺利,评估工作也为完成2020年《规划》目标提供了重要技术支撑。  相似文献   

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以流域为单元进行水资源综合规划和管理是实现水环境改善的重要途径。本文以太湖流域第二大省界湖泊—淀山湖为例,在综合分析流域水环境质量基础上,利用GIS 分析工具划分流域治理片区并制定分区管控策略。根据流域所含骨干河流流向、骨干河流与淀山湖交汇特点、上中下游不同河段及镇域行政边界,将淀山湖流域分为吴淞江流域、千灯浦- 淀山湖流域、昆南湖荡流域、元荡湖荡流域、太浦河流域五大片区138 个子评价单元。通过水环境容量与压力两类空间叠加分析,构建形成污染重点减排区、污染综合治理区、产业绿色化提升区、生态环境保育区等四个类型区域,并提出差异化的产业准入和环境治理措施。本研究不仅为以流域为治理单元的水环境治理规划提供了较为可行的技术体系,而且为太湖流域水环境综合整治思路创新提供了可借鉴的案例。  相似文献   

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复杂信息系统各功能正常运行依赖于内部各数据处理节点之间的高效协作和数据交互。针对复杂信息系统运行情况评估的需求,提出了一种基于工作流模型的评估方法,能够依据系统运行过程中各节点之间的数据交互关系建立模型,通过该模型对系统的记录数据进行自动化处理,实现系统整体运行情况、各节点运行情况以及各项功能完成情况的统计和分析,实现故障问题的隔离和定位。  相似文献   

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Abstract: The Soil and Water Assessment Tool (SWAT) model was evaluated for estimation of continuous daily flow based on limited flow measurements in the Upper Oyster Creek (UOC) watershed. SWAT was calibrated against limited measured flow data and then validated. The Nash‐Sutcliffe model Efficiency (NSE) and mean relative error values of daily flow estimations were 0.66 and 15% for calibration, and 0.56 and 4% for validation, respectively. Also, further evaluation of the model’s estimation of flow at multiple locations was conducted with parametric paired t‐test and nonparametric sign test at a 95% confidence level. Among the five main stem stations, four stations were statistically shown to have good agreement between predicted and measured flows. SWAT underestimated the flow of the fifth main stem station possibly because of the existence of complex flood control measures near to the station. SWAT estimated the daily flow at one tributary station well, but with relatively large errors for the other two tributaries. The spatial pattern of predicted flows matched the measured ones well. Overall, it was concluded from the graphical comparisons and statistical analyses of the model results that SWAT was capable of reproducing continuous daily flows based on limited flow data as is the case in the UOC watershed.  相似文献   

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生态红线管控绩效考核技术方案及制度保障研究   总被引:2,自引:1,他引:2  
基于生态红线管控绩效考核必要性的分析,在尽可能规避目前我国环境绩效考核诸多弊端的前提下,制定了生态红线绩效考核框架及技术方案:从绩效考核主体、客体、考核内容与考核方法等方面完成了生态红线绩效考核框架的构建,确定了考核指标、计量模型和考核标准,并详细探讨了考核程序、考核成果的管理与应用等问题。研究旨在为地方政府实施生态红线管控绩效考核提供支撑。  相似文献   

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An Experiment in Participative Environmental Decision Making   总被引:2,自引:0,他引:2  
Summary The paper presents a method of participatory decision-making involving the authorities at local level, experts and the public. It studies how to solve the problems caused by the heterogeneity of the parties taking part in the decision-making process. The method builds on mutual learning and consideration among the participants following a systematic approach led by a moderator. The method was tested at a workshop simulating a real-life situation. The test case studied at the workshop was the problem of identifying the best site for a low and intermediate level radioactive waste repository among three alternatives. The learning phase was the Krško Nuclear Power Plant cooling problem. The results show that the participants were able to reach agreement on the prioritisation of the alternatives and to end up with suprisingly complex and fully reasonable decision models. We believe that this was achieved particularly due to the well defined procedure that guided the decision-making process, and the ability of all participants to see the influence of their views on the decision model.  相似文献   

14.
吴勇  刘娉 《中国环境管理》2024,16(1):145-153
为促进流域的司法保护,我国一些地方法院成立了专门的流域环境法庭。但从流域环境法庭和流域环境巡回法庭的实践情况来看,还不能满足流域整体性保护的需要,也不能适应流域法的发展需求。我国流域司法机制建设,宜从流域环境法庭逐渐转到流域环境法院。流域环境法院的建立在我国环境司法专门化进程中具有必要性和可行性。按照流域法的保护理念和环境司法专门化的要求,流域环境法院的建设首先要合理设置审判机构,其次要科学设计程序制度,为流域生态环境保护提供强有力的司法保障。  相似文献   

15.
黄本生  王里奥  李晓红 《四川环境》2003,22(3):57-60,68
随着社会的进步和经济的发展,随之带来的城市污染也日益严重,进行城市流域科学、合理的规划和综合整治,具有十分重要的意义。本文以重庆市清水溪流域为例,在分析流域现状的基础上,结合重庆市总体规划,提出了城市流域综合整治的措施:沿岸两例污水管网建设、两岸垃圾整治、河道清淤及防洪、两岸绿化带及景点建设、水土保持、水源地涵养区规划与建设等。并从生态、社会和经济方面进行分析,对产生的环境效益进行评价:整治工程建成后清水溪流域接纳的污染物CODcr将削减857lt/a、总磷削减160t/a、SS削减6156t/a;流域生态环境大大改善;同时将带来巨大的直接经济效益;整治工程是为民造福的民心工程。  相似文献   

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Chaffin, B.C., R.L. Mahler, J.D. Wulfhorst, and B. Shafii, 2011. Collaborative Watershed Groups in Three Pacific Northwest States: A Regional Evaluation of Group Metrics and Perceived Success. Journal of the American Water Resources Association (JAWRA) 48(1): 113‐122. DOI: 10.1111/j.1752‐1688.2011.00599.x Abstract: Watershed management through collaborative groups has become important throughout the United States over the past two decades. Although several studies of Oregon and Washington watershed groups exist, a definitive regional analysis of Pacific Northwest (PNW) watershed groups’ success is lacking. This paper uses data collected from a single survey instrument to determine the status, structure, and success of watershed groups in Idaho, Oregon, and Washington, respectively. Results indicate that watershed group member satisfaction with elements of group structure correlates with levels of perceived group success. Strong leadership within a group and a clear mission statement also indicate higher levels of perceived success. Contrasting realized successes among PNW watershed groups with metrics of perceived success constructed from survey data define watershed groups’ missions and goals and is validated by analysis of the Washington State planning groups’ responses. Overall, PNW watershed groups identified themselves as largely successful. Therefore, the structure, function, and operation identified as characteristic of PNW watershed groups could be used as a model for developing watershed group programming in regions with similar conditions.  相似文献   

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The Phase 5.3 Watershed Model simulates the Chesapeake watershed land use, river flows, and the associated transport and fate of nutrient and sediment loads to the Chesapeake Bay. The Phase 5.3 Model is the most recent of a series of increasingly refined versions of a model that have been operational for more than two decades. The Phase 5.3 Model, in conjunction with models of the Chesapeake airshed and estuary, provides estimates of management actions needed to protect water quality, achieve Chesapeake water quality standards, and restore living resources. The Phase 5.3 Watershed Model tracks nutrient and sediment load estimates of the entire 166,000 km2 watershed, including loads from all six watershed states. The creation of software systems, input datasets, and calibration methods were important aspects of the model development process. A community model approach was taken with model development and application, and the model was developed by a broad coalition of model practitioners including environmental engineers, scientists, and environmental managers. Among the users of the Phase 5.3 Model are the Chesapeake watershed states and local governments, consultants, river basin commissions, and universities. Development and application of the model are described, as well as key scenarios ranging from high nutrient and sediment load conditions if no management actions were taken in the watershed, to low load estimates of an all‐forested condition.  相似文献   

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Economic costs, water quantity/quality benefits, and cost effectiveness of agricultural best management practices (BMPs) at a watershed scale are increasingly examined using integrated economic‐hydrologic models. However, these models are typically complex and not user‐friendly for examining the effects of various BMP scenarios. In this study, an open source geographic information system (GIS)‐based decision support system (DSS), named the watershed evaluation of BMPs (WEBs), was developed for creating BMP scenarios and simulating economic costs and water quantity/quality benefits at farm field, subbasin, and watershed scales. This DSS or WEBs interface integrated a farm economic model, the Soil and Water Assessment Tool (SWAT), and an optimization model within Whitebox Geospatial Analysis Tools (GAT), an open source GIS software. The DSS was applied to the 14.3‐km2 Gully Creek watershed, a coastal watershed in southern Ontario, Canada that drains directly into Lake Huron. BMPs that were evaluated included conservation tillage, nutrient management, cover crop, and water and sediment control basins. In addition to assessing economic costs, water quantity/quality benefits, and cost effectiveness of BMPs, the DSS can be also used to examine prioritized BMP types/locations and corresponding economic and water quantity/quality tradeoffs in the study watershed based on environmental targets or budget constraints. Further developments of the DSS including interface transfer to other watersheds are also discussed. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   

19.
Kang, Min‐Goo and Gwang‐Man Lee, 2011. Multicriteria Evaluation of Water Resources Sustainability in the Context of Watershed Management. Journal of the American Water Resources Association (JAWRA) 47(4):813‐827. DOI: 10.1111/j.1752‐1688.2011.00559.x Abstract: To evaluate water resources sustainability at the watershed scale within a river basin’s context, the Water Resources Sustainability Evaluation Model is developed. The model employs 4 criteria (economic efficiency, social equity, environmental conservation, and maintenance capacity) and has 16 indicators, integrating them using their relative weights. The model is applied to evaluate the water resources sustainability of watersheds in the Geum River basin, South Korea. A geographic information system is employed to efficiently build a database for the indicators, and the values of the indicators are normalized using the probability distribution functions fitted to the datasets of the indicators. The evaluation results show that, overall, the water resources sustainability of the watersheds in the upper basin is better than other areas due to the good environmental conditions and the dam management policies of South Korea. The analysis of the correlations among the model’s components and the comparison between the results of the model and the Water Poverty Index show that the model can provide reasonable evaluation results for the water resources sustainability of watersheds. Consequently, it is concluded that the model can be an effective tool for evaluating the states of water resource management from the perspective of sustainable development and provide a basis on which to create policies for improving any inadequacies in watersheds.  相似文献   

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