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环境流计算新方法:水文变化的生态限度法 被引量:13
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作者 董哲仁 赵进勇 张晶 《水利水电技术》 CSCD 北大核心 2017年第1期11-17,共7页
水文变化的生态限度框架(ELOHA)是环境流理论最新成果。ELOHA要求对河流按照水文情势特征进行分类,相同类型河流的水文—生态关系具有相似性。ELOHA还要求对开发前后水文情势变化进行分析,计算现状水文条件与基准水文条件的偏离程度。EL... 水文变化的生态限度框架(ELOHA)是环境流理论最新成果。ELOHA要求对河流按照水文情势特征进行分类,相同类型河流的水文—生态关系具有相似性。ELOHA还要求对开发前后水文情势变化进行分析,计算现状水文条件与基准水文条件的偏离程度。ELOHA提出了水文情势变化预期生态响应的若干假定,总结了一套为建立水文—生态关系采用的生态指标。在建立大型水文和生物数据库的基础上,运用统计学方法拟合水文—生态函数关系。最后,各利益相关者对水文变化引起的生态风险进行评估,认定可以接受的生态风险水平,再依据水文—生态曲线,确定环境流标准。 展开更多
关键词 环境流评价 水文变化的生态限度 生态指标 水文情势改变 生态响应
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Numerical simulation of construction project environmental impact on the tides and tidal currents in Aojiang offshore of Wenzhou
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作者 吕和娜 汪一航 +2 位作者 张钊 单慧洁 岳云飞 《Marine Science Bulletin》 CAS 2014年第2期13-27,共15页
This paper have collected the measured tides and certain tidal current data in different stages of many projects during past three to five years near the Aojiang River. The harmonic method is used to analyze tide and ... This paper have collected the measured tides and certain tidal current data in different stages of many projects during past three to five years near the Aojiang River. The harmonic method is used to analyze tide and tidal current data observed at five stations in the sea adjacent to Aojiang River. The results show that the tide is mainly regular and semidiumal in the sea near Aojiang of Wenzhou. The tidal amplitudes of M2 constituent are between 170 cm - 193 cm and the lags are between 260~ - 280~, According to the comparison of analytical results of harmonic constants of these stations in 2007, 2010 and 2011, the maximum change of tidal amplitudes and phase-lag range for the main semidiurnal tides (M2, $2, N2), the diurnal tide (K1, O1) and the shallow water tide (M4, MS4, M6) are 1.8 cm - 4.4 cm and 3~ - 7~, respectively. After analyzing the tide and tidal current characteristics of Aojiang River, this paper uses an unstructured grid and Finite-Volume Coastal Ocean Model (FVCOM) to test the results of simulation. The simulated results agree well with the measured data. The new shoreline and depth which are produced by the construction projects closed in important major years, and the tide and tidal current field for the new shoreline and depth are constructed, which describe the superimposed influences of construction engineering in Aojiang estuary. 展开更多
关键词 Aojiang estuary tide and tidal current environmental impact numericalsimulation POST-EVALUATION
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Assessment of temporal and spatial variations in surface water quality using multivariate statistical techniques: A case study of Nenjiang River basin, China 被引量:2
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作者 郑力燕 于宏兵 王启山 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3770-3780,共11页
Assessment of temporal and spatial variations in surface water quality is important to evaluate the health of a watershed and make necessary management decisions to control current and future pollution of receiving wa... Assessment of temporal and spatial variations in surface water quality is important to evaluate the health of a watershed and make necessary management decisions to control current and future pollution of receiving water bodies. In this work, surface water quality data for 12 physical and chemical parameters collected from 10 sampling sites in the Nenjiang River basin during the years(2012-2013) were analyzed. The results show that river water quality has significant temporal and spatial variations. Hierarchical cluster analysis(HCA) grouped 12 months into three periods(LF, MF and HF) and classified 10 monitoring sites into three regions(LP, MP and HP) based on the similarity of water quality characteristics. The principle component analysis(PCA)/factor analysis(FA) was used to recognize the factors or origins responsible for temporal and spatial water quality variations. Temporal and spatial PCA/FA revealed that the Nenjiang River water chemistry was strongly affected by rock/water interaction, hydrologic processes and anthropogenic activities. This work demonstrates that the application of HCA and PCA/FA has achieved meaningful classification based on temporal and spatial criteria. 展开更多
关键词 Nenjiang River basin water quality hierarchical cluster analysis(HCA) principal component analysis(PCA) factor analysis
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IMPACT EVALUATION OF HAIZUKA DAM ON ITS UP STREAM A CASE STUDY IN HIROSHIMA PREFECTURE, JAPAN
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作者 Forood AZARI DEHKORDI Nobukazu NAKAGOSHI 《Chinese Geographical Science》 SCIE CSCD 2004年第4期350-354,共5页
Japan ranks fifth in the world for the number of large dams. Environmental impacts of large dams are known, such as enormous losses of water or disruption of fish spawning, however, impacts of the dams on their up str... Japan ranks fifth in the world for the number of large dams. Environmental impacts of large dams are known, such as enormous losses of water or disruption of fish spawning, however, impacts of the dams on their up streams are functions of topography of the up stream. Haizuka Dam is located in Hiroshima Prefecture, Japan and its implementation will start in 2006. This large dam influences its up stream through dam making activities, which occurs in order and with different spatial presences that were categorized into chronological and spatial impacts. In this case study, spatial impacts were further divided into horizontal and vertical ones. The horizontal impacts were identified as new roads, diversion tunnel, dam lake, and submerged cultivated land, while vertical impacts were recognized as submerged historical monuments, slope protections, dam body, and deforested area in the reservoir. There were convergences of spatial and temporal impacts, however, the extent of the impacts was limited to the lake boundary. 展开更多
关键词 dam impact up stream Haizuka Dam JAPAN
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Strategic Bidding Model for Power Generation Company Based on Repast Platform
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作者 Zhigang Zhang Guangwen Ma 《Journal of Systems Science and Information》 2008年第4期381-388,共8页
: The bidding strategies of power generations in the market are a dynamic and complex problem. It is difficult to analyze and compute with the traditional mathematical methods, which is conspicuous in the middle or l... : The bidding strategies of power generations in the market are a dynamic and complex problem. It is difficult to analyze and compute with the traditional mathematical methods, which is conspicuous in the middle or long-term transactions. This paper pro- poses a modelity which is the middle or long-term bidding strategy in two-tiers electricity market that is based on the optimal power flow (OPF). Uncertainties in the outside world are regarded as the agent (Agent) of "external environment." Under this conditions, Agent through environment evaluation judges to select viable strategic. Through learning from experiences and opponent's behaviors, Agent guides the purpose of the best production. The adaptability and superiority of this model is tested based on Repast with a standard IEEE-5 bus 6 notes test system. 展开更多
关键词 electricity market reinforcement learning RL AGENT REPAST
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