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Science china(Technological Sciences) 2009年第11期52卷 3401-3405页

作者： men baohui1 & liu changming2.1 renewable energy institute,{1., Beijing 102.06, china 2 Key Laboratory of Water Cycle and Related Land Surface Process, institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 1.01.1. china 1. renewable {1. institute North China Electric Power University Beijing 102206 China 2. Key Laboratory of Water Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Transporting sediment is a natural function of the river. To maintain the normal evolution of the river certain amount of water flow is required, which is called the instream flow requirements for transporting sediment (IFRTS). We defined the permitting flow velocity by the conception of IFRTS, and also put forward the ecological hydraulic radius model (EHRM) to estimate IFRTS. The calculating process of EHRM is explained by the example of Daofu Hydrological Station on Xianshui branch of Yalong River in the west line first-stage construction of South-north Water Transfer Project. The result shows that the IFRTS occupied 29.7%―59.5% of annual mean discharge in flood season, the average of IFRTS was about 1.0.2 m3/s during 1.66―1.87, it is close to the IFRTS 90 m3/s calculated by IFRTS conception. Hence, it is feasible to use EHRM to calculate IFRTS.

关键词： ecological hydraulic radius model (EHRM) instream flow requirements for transporting sediment (IFRTS) permitting flow velocity ecological hydraulic radius for transporting sediment

A new criterion for defining the breakpoint of the wetted perimeter-discharge curve and its application to estimating minimum instream flow requirements

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Science china(Technological Sciences) 2012年第10期55卷 2686-2693页

作者： men {1. liu changming LIN ChunKun National Engineering Laboratory for Biomass Power Generation EquipmentRenewable Energy InstituteNorth China Electric Power UniversityBeijing 102206China Key Laboratory of Water Cycle and Related Land Surface ProcessInstitute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Water Science Beijing Normal UniversityBeijing 100875China

The wetted perimeter method(WPM) is used in hydrology and hydraulics to calculate instream *** WPM requires few *** requires only the values of the wetted perimeter,flow and water level,which can be obtained from the hydrologic stations of the river in *** addition,the WPM is not limited by the impacts of human activities on the river ***,this method is generally suitable for the current conditions in ***,the process of applying the WPM involves two key aspects:how to plot the curve describing the relationship between the wetted perimeter and the discharge and how to confirm the breakpoint of the wetted perimeter-discharge *** traditional method is to calculate the curvature or the slope of the wetted perimeter-discharge curve to obtain the minimum *** to this method,the minimum flow corresponds to the point of maximum curvature or to the point at which the slope of the curve is equal to *** wetted perimeter-discharge curve of a natural river is only part of the complete ***,the instream flow calculated by the traditional method is the minimum or maximum *** new criterion for defining the breakpoint of the wetted perimeter-discharge curve is that the slope at the breakpoint is a relative maximum,the second-largest *** discharges at the breakpoints corresponded to the minimum flow levels required to maintain the ecological function of the *** minimum instream flow requirements(MIFRs) of four typical reaches,Zhuba,Daofu,Ganzi and Zumuzu hydrological stations on the West Course of the First Stage Project of the South-{1. Water Transfer Project(WCFSPSNWTP),are calculated using an improved wetted perimeter method(IWPM).The results show that the MIFRs of Zhuba,Daofu,Ganzi and Zumuzu are approximately 9.06-1..5 m 3 s-1.20.7-43.5 m3 s-1.38.8-77.2 m 3 s-1.and 40.4-59.5 m 3 s-1.corresponding to 1..7%-33.9%,1..2%-37.6%,1..4%-28.4% and 1..5%-30.2%,respectively of the annual average flow(A

关键词： wetted perimeter method slope curvature the West Course of the First Stage Project of South-north Water Transfer Project (WCFSPSNWTP) Tennant method

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东北电网水库群发电调度风险分析

水电能源科学 2010年第5期28卷 163-165页

作者：段金长宋雅坪纪昌明张验科国网电力科学研究院江苏南京210003 东北电网有限公司调度通信中心辽宁沈阳110006 华北电力大学可再生能源学院北京102206

针对水库调度风险分析一直为水库调度理论研究的重点及难点之一,借助东北电网水调自动化项目及多年水库调度运行经验,结合风险分析的基础理论,采用蒙特卡罗法研究了发电调度风险分析,选取一系列风险指标建立了发电调度风险分析模型,并... 详细信息

针对水库调度风险分析一直为水库调度理论研究的重点及难点之一,借助东北电网水调自动化项目及多年水库调度运行经验,结合风险分析的基础理论,采用蒙特卡罗法研究了发电调度风险分析,选取一系列风险指标建立了发电调度风险分析模型,并开发了相应风险分析软件。通过在东北电网水库调度自动化系统的应用,证明了该模型计算结果的合理性,为发电调度风险分析提供了一种合理可行的途径,也给调度管理人员提供了决策支持。

关键词：风险分析风险指标水库调度风险分析模型发电调度风险分析东北电网

交流电压下油纸绝缘放电发展过程中电-磁-声特征参量的变化规律

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高电压技术 2024年第8期50卷 3805-3813页

作者：江长明黄猛郝震李雨刘健马鑫晟国家电网有限公司华北分部北京100053 华北电力大学新能源电力系统全国重点实验室北京102206 华北电力科学研究院有限责任公司北京100045

沿面放电是变压器油纸绝缘结构最严重的放电故障类型之一。为了准确获取交流电压下油纸绝缘沿面放电发展过程中特征参量的变化规律,搭建了沿面放电发展过程模拟试验平台并建立了1.能够满足对放电发展过程中电、磁、声这3种物理量同步... 详细信息

沿面放电是变压器油纸绝缘结构最严重的放电故障类型之一。为了准确获取交流电压下油纸绝缘沿面放电发展过程中特征参量的变化规律,搭建了沿面放电发展过程模拟试验平台并建立了1.能够满足对放电发展过程中电、磁、声这3种物理量同步在线监测需求的测量系统。在此基础上,提取沿面放电发展过程中多物理参量的典型特征,通过对特征参量全过程幅值变化规律的分析对放电过程进行阶段划分,并给出相应的阶段特征及机理概述。试验结果表明,通过分析多参量典型特征及变化规律可以将沿面放电发展过程划分为4个阶段:微小能量放电阶段、低能量放电阶段、高能量放电阶段、临近击穿阶段,阶段特征与电荷分布及绝缘材料耐受强度有关。相比常规单参量监测手段,多参量同步检测方法为变压器沿面故障诊断和及时预警提供了更可靠准确的参考依据。

关键词：变压器油纸绝缘沿面放电多参量信号变化规律阶段划分

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基于云理论的北京市水环境承载力综合评价

水力发电 2019年第11期45卷 4-8页

作者：门宝辉丽娜·托库华北电力大学可再生能源学院

随着人类社会和经济的发展,水资源消耗及水污染的问题很大程度上降低了人类的生活质量,开展水环境承载力的研究可为协调人与自然的矛盾,以及城市经济的绿色发展提供理论依据和数据支持。基于驱动力-压力-状态-响应模型构建评价指标体系... 详细信息

随着人类社会和经济的发展,水资源消耗及水污染的问题很大程度上降低了人类的生活质量,开展水环境承载力的研究可为协调人与自然的矛盾,以及城市经济的绿色发展提供理论依据和数据支持。基于驱动力-压力-状态-响应模型构建评价指标体系,结合熵权法求取指标权重,运用云理论推算出2004年~2.17年北京市各年的水环境承载力水平。结果表明,近1.年来,北京市的水环境承载力整体呈现上升趋势,2004年最低,2.10年达到较高水平后趋于稳定;虽然北京市水环境承载力水平得到了一定的改善,但整体仍处于超载状态。

关键词：水环境承载力综合评价云理论北京市

Effect of long-term fluorination on surface electrical performance of ethylene propylene rubber

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High Voltage 2019年第4期4卷 339-344页

作者： Rujia men Zhipeng Lei Tao Han Davide Fabiani Chuanyang Li Simone Vincenzo Suraci Jian Wang Shanxi Key Laboratory of Mining electrical Equip{1.t and Intelligent Control College of Electrical and Power EngineeringTaiyuan University of TechnologyTaiyuan 030024People's Republic of China Department of {1.al Electronicand Information Engineering‘Guglielmo Marconi’University of BolognaViale Risorgimento 2Bologna 40136Italy Key Laboratory of Smart Grid of Education Ministry School of Electrical and Information Engineering Tianjin UniversityTianjin 300072People's Republic of China State Key Laboratory of Alternate electrical {1. System with renewable energy Sources North China Electric Power UniversityChangping DistrictBeijing 102206People's Republic of China

To investigate the effect of fluorination on surface electrical performance of ethylene propylene rubber(EPR),four pieces of EPR speci{1.s are prepared and fluorinated for different duration ranging from 1.0 min to 480 *** surface morphology and ele{1.t compositions of experi{1.tal speci{1.s are *** surface potential decay and complex permittivity are *** tracking discharge property and the erosion properties after tracking test are *** surface charge transport and electrical property tailoring mechanism are *** results show that when the fluorination duration is from 1.0 min to 360 min,the surface morphology gradually becomes flat and compact with time,and the surface resistance to electrical tracking is *** an excessive fluorination with the duration of 480 min leads to a significant increase in surface conductivity and a weakening in the resistance to electrical tracking,which is mainly due to a change in surface *** recom{1.ded fluorination duration for an optimised surface property is between 240 and 360 min for EPR speci{1..

关键词： electrical propylene rubber

基于模糊集对分析的京津冀水资源可持续利用评价

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华北水利水电大学学报（自然科学版） 2018年第4期39卷 79-88页

作者：门宝辉刘焕龙华北电力大学可再生能源学院北京102206

京津冀地区是重度"资源型"缺水地区,人均水资源量显著不足,评价该区域水资源可持续利用的现状及发展趋势,可为京津冀地区水资源的管理提供更好的理论依据和数据支撑。结合社会-经济-生态复合系统建立评价指标体系,采用粗糙集和模糊理论... 详细信息

京津冀地区是重度"资源型"缺水地区,人均水资源量显著不足,评价该区域水资源可持续利用的现状及发展趋势,可为京津冀地区水资源的管理提供更好的理论依据和数据支撑。结合社会-经济-生态复合系统建立评价指标体系,采用粗糙集和模糊理论相结合的方法确定指标权重,分别应用基于属性识别法和同异反层次法的模糊集对分析理论对京津冀地区2004—2.15年的水资源可持续利用情况进行评价,并在计算综合联系度过程中引入可变模糊集理论中的S型函数,最后用Spearman相关系数法对得到的多组结果进行相关性分析。结果表明:近1.年,京津冀地区的水资源可持续利用水平整体呈现上升趋势;基于S型函数的模糊集对分析法在京津冀地区水资源可持续利用评价中是可行的。

关键词：集对分析法可变模糊集理论水资源可持续利用京津冀地区

Bootstrapped Multi-Model Neural-Network Super-Ensembles for Wind Speed and power Forecasting

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energy and {1. Engineering 2014年第11期6卷 340-348页

作者： Zhongxian men Eugene Yee Fue-Sang Lien Hua Ji Yongqian {1. Waterloo CFD Engineering Consulting Inc. Waterloo Ontario Canada Department of Mechanical & Mechatronics Engineering University of Waterloo Waterloo Onatrio Canada Defence Research and Development Canada Suffield Research Centre Medicine Hat Alberta Canada School of renewable {1. North China Electric Power University Beijing China

The bootstrap resampling method is applied to an ensemble artificial neural network (ANN) approach (which combines machine learning with physical data obtained from a numerical weather prediction model) to provide a multi-ANN model super-ensemble for application to multi-step-ahead forecasting of wind speed and of the associated power generated from a wind turbine. A statistical combination of the individual forecasts from the various ANNs of the super-ensemble is used to construct the best deterministic forecast, as well as the prediction uncertainty interval associated with this forecast. The bootstrapped neural-network methodology is validated using measured wind speed and power data acquired from a wind turbine in an operational wind farm located in northern china.

关键词： Artificial Neural Network Bootstrap Resampling Numerical Weather Prediction Super-Ensemble Wind Speed power Forecasting

考虑水流时滞的梯级水电站水库群短期发电优化调度

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电力系统自动化 2020年第6期44卷 45-51页

作者：张验科刘源纪昌明张佳新华北电力大学可再生能源学院北京市102206

在梯级水电站水库群短期发电优化调度过程中,为了规避水流时滞的影响,基于线性空间原理,建立了上级水库的出库流量、区间入流、下库水位所构成的空间与下级水库的入库流量空间的映射函数,并综合应用数据挖掘中的人工神经网络、K-means和... 详细信息

在梯级水电站水库群短期发电优化调度过程中,为了规避水流时滞的影响,基于线性空间原理,建立了上级水库的出库流量、区间入流、下库水位所构成的空间与下级水库的入库流量空间的映射函数,并综合应用数据挖掘中的人工神经网络、K-means和Relief方法对其进行求解,构建了考虑水流时滞的梯级水电站水库群短期发电优化调度模型。应用于雅砻江流域锦官电源组短期发电优化调度的算例分析表明,所建立的模型能够提高短期发电优化调度方案制作的精度。

关键词：水流时滞梯级水电站水库群短期发电优化调度线性空间

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考虑动态水流滞时的梯级水库群日优化调度

水力发电学报 2019年第8期38卷 37-47页

作者：纪昌明刘源张验科梁小青华北电力大学可再生能源学院北京102206 甘肃民族师范学院物理与水电工程系甘肃合作747000

梯级水电站水库群短期优化调度中,通常忽略梯级水库间水流滞时的影响或将其作为常数进行考虑,实际上水流滞时是随着上级水库出库流量大小、河道槽蓄状态、区间入流等因素动态变化,想要准确预测下级水库入流是存在困难的。因此,采用多种... 详细信息

梯级水电站水库群短期优化调度中,通常忽略梯级水库间水流滞时的影响或将其作为常数进行考虑,实际上水流滞时是随着上级水库出库流量大小、河道槽蓄状态、区间入流等因素动态变化,想要准确预测下级水库入流是存在困难的。因此,采用多种方法筛选出影响下级水库入库流量的主要因素作为输入,利用神经网络建立输入与下级水库入库流量之间的动态函数关系。以锦东和官地水库梯级为例,建立考虑动态滞时的梯级水电站水库群日优化调度模型,并采用逐次优化法对采用动态滞时与固定滞时的优化方案进行求解和对比分析。结果表明:与固定滞时相比,动态滞时下能够更准确地描述梯级水库间的水流联系,同时能够在一定程度上增加梯级水电站水库群发电效益。

关键词：短期优化调度水流滞时神经网络梯级水电站逐次优化法