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Journal of Geographical Sciences 2024年第8期34卷 1537-1557页

作者： SUN Zhaohua LI Zhiqing CHEN Li fan jiewei LIU Ya State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China Yellow River Water&Hydropower Development Group Co. Ltd.Jiyuan 459017HenanChina Changjiang River Scientific Research Institute Wuhan 430010China

Floodplain lakes are important water storage areas in lowland regions that often undergo geomorphologic evolution,and timely topographic data are generally *** this study,to assess the impacts of lakebed deformation on hydraulic performance in Dongting Lake,a set of semi-empirical methods was proposed to establish performance graphs(PGs)using only hydrological *** methods were used to evaluate the changes in water level,storage capacity,and flood detention ability in Dongting Lake caused by topographic adjustment after the Three Gorges Reservoir *** methods showed that PGs can effectively simulate the water level and outflow processes of Dongting Lake with Nash-Sutcliffe efficiency coefficients(NSEs)above 0.9.A comparison of the estimated water level and discharge using PGs from different periods suggested that bed erosion in Dongting Lake caused water level decreases of 0.18 m and 0.32 m during the flood and dry seasons,*** the magnitude of erosion at high elevations in the lake is small,the impacts of bed adjustment on the storage capacity and flood detention ability are not currently *** study showed that the hydraulic performance of a floodplain lake can be evaluated independently of topographic data under the condition of no reverse flows or negative watersurface slopes.

关键词： Dongting Lake hydraulic performance graph bed adjustment semi-empirical approach backwater effect

Analysis of critical river discharge for saltwater intrusion control in the upper South Branch of the Yangtze River Estuary

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Journal of Geographical Sciences 2020年第5期30卷 823-842页

作者： SUN Zhaohua fan jiewei YAN Xin XIE Cuisong State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Shanghai Water Affairs Bureau Shanghai 200050China

Saltwater intrusion in the estuary area threatens the use of freshwater *** river discharge increases to a critical value,then saltwater intrusion frequency and salinity level *** this study,long-term river discharge and tidal range data in the Yangtze River Estuary(YRE)and salinity data obtained in the upper South Branch of the YRE were used to analyze the characteristics of different variables and the basic law of their *** methods,namely,the material analysis method and empirical models,were applied to determine the critical river discharge for saltwater intrusion *** are as follows:(1)the salinity might exceed the drinking water standard of China when the river discharge was less than 30,000 m^3/*** 69%of salinity excessive days occurred when the river discharge was less than 15,000 m^3/s;(2)the tidal range in the YRE roughly varied in sinusoidal pattern with a 15-day cycle *** relationship existed between daily salinity(chlorinity)and daily mean tidal *** these two features with the cumulative frequency statistics of tidal ranges,it was showed that notable saltwater intrusion occurred when the tidal range was more than 2.7 m at Qinglonggang ***,the critical discharge was found to be slightly higher than 11,000 m^3/s;(3)various of empirical models for salinity prediction could be chosen to calculate the critical *** values obtained by different models were in the range of 11,000–12,000 m^3/s;(4)the proposed critical discharge to reduce notable saltwater intrusion was 11,500 m^3/*** the Three Gorges Reservoir operation,the minimum river discharge into the YRE in 2008–2017 was below the critical discharge,thereby suggesting an increase in the minimum river discharge by reservoir regulation in drought periods.

关键词： critical discharge saltwater intrusion control empirical model the Yangtze River Estuary

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考虑回水影响的河道水位流量关系确定方法

水科学进展 2021年第2期32卷 259-270页

作者：孙昭华周歆玥范杰玮熊海滨谈广鸣武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

为评估长江中游受回水影响河段内河床调整引起的水位变幅,提出一种仅依赖水文资料的多值型水位—流量关系确定方法。结果表明:单值型关系无法区分河床调整与回水因素的影响,而已有的多值型方法可操作性受限;长江中游河道断面的河宽与水... 详细信息

为评估长江中游受回水影响河段内河床调整引起的水位变幅,提出一种仅依赖水文资料的多值型水位—流量关系确定方法。结果表明:单值型关系无法区分河床调整与回水因素的影响,而已有的多值型方法可操作性受限;长江中游河道断面的河宽与水深之间,以及流量与糙率之间都具有明显制约关系,依据这些制约关系对恒定渐变流方程简化,可得到上下游水位与河段内流量之间的多值型函数关系;确定出多年平均水位—流量关系之后,计算水位与实测水位之间的残差能够反映河床调整的影响;在长江中游3个不同类型典型河段的应用表明,河床稳定情况下的计算与实测水位之间决定系数R 2值超过0.99,河床调整情况下,新方法更易识别水位变幅。

关键词：回水顶托水位—流量关系河床调整水位变幅长江中游

微拟球藻高pH沉降采收的响应面法优化及其培养基的循环利用

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渔业现代化 2015年第2期42卷 16-22页

作者：胡群菊向文洲杨芳芳贾其坤吴华莲李涛何慧范杰伟中国科学院南海海洋研究所热带海洋生物资源可利用重点实验室广东省海洋药物重点实验室广州510301 中国科学院大学北京100049

针对微藻采收成本高的难题,以一株微拟球藻(Nannochloropsis sp.)为研究材料,采用响应面法优化该藻株的高p H沉降采收技术,并初步评估其培养基的循环利用。结果显示,藻株培养液的细胞密度、沉降p H及处理时间3种因素对其生物量采收率(B... 详细信息

针对微藻采收成本高的难题,以一株微拟球藻(Nannochloropsis sp.)为研究材料,采用响应面法优化该藻株的高p H沉降采收技术,并初步评估其培养基的循环利用。结果显示,藻株培养液的细胞密度、沉降p H及处理时间3种因素对其生物量采收率(BRR)具有显著影响。预测最优采收参数为:藻细胞光密度OD750=2.08;沉降p H=12.20;处理时间12 h,预测BRR为98.97%,验证实验实测BRR为98.31%。采收藻细胞后的上清液经过滤、p H调整及营养盐补充后,探究高p H采收后的培养基上清液的循环利用。与新鲜培养基相比,高p H采收回收培养基中的藻细胞生长和油脂含量有小幅度的降低,但总脂分级特性及脂肪酸组成无显著差异。该藻株的高p H采收及其培养基的回收利用方法具有可行性。

关键词：微拟球藻高pH采收响应面法培养基回收生物柴油 EPA

自平衡策略的电流互感器取能调速风冷装置设计

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电机与控制学报 2024年第5期28卷 1-8页

作者：何杰伟刘自程黄秋萍刘杉姜喆刘志刚华中科技大学电气与电子工程学院湖北武汉430074 国网智能电网研究院有限公司北京100084 江苏腾炎电气有限公司江苏苏州215000

随着我国电力系统输电量逐年上升,输电网络中的换流变压器阀侧套管等关键设备部件热功率也随之增大,因此有必要设计开发散热风机等设备,实现过热故障多发点的主动散热。设计研发一种电流互感器(CT)取能调速风冷装置,利用CT从输电线路上... 详细信息

随着我国电力系统输电量逐年上升,输电网络中的换流变压器阀侧套管等关键设备部件热功率也随之增大,因此有必要设计开发散热风机等设备,实现过热故障多发点的主动散热。设计研发一种电流互感器(CT)取能调速风冷装置,利用CT从输电线路上获取能量为散热风机供能,以解决输电线路现场常规电源无法使用的难题。针对CT的取能能力随着输电线路电流不断变化且不受控的问题,设计一种功率主动自平衡新策略,通过利用负载的控制自由度来适应CT二次侧电流的宽变化范围,从而扩展装置的稳定运行区间,提升电源的取能能力。将装置套装在交流输电母排上进行实验验证,母排电流的有效值在上千安培范围内变化,装置始终稳定且保持60%以上的功率容量利用率。

关键词：换流变压器阀侧套管电流互感器取能电源调速风冷功率平衡稳定运行区间

A　Study　on　Increasing　Economic　Benefit　of　a　State－owned　Enterprise　in　Liaoning　Province

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Systems Science and Systems Engineering 1995年第2期5卷 97-105页

作者： ZHANG jiewei (Dalian University of Technology,Dalian,116024,China)fan Jin(Institute of Technology of Yangzhou University Yangzhou,225001,China)

In this paper,Delphi method is used to study the reasons for lower economic benefit and plots for increasing economic benefit of a state-owned enterprise.

关键词： economic benefit Delphi method reasons plots.

Psychoacoustic Study on Contribution of fan Noise to Engine Noise

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Chinese Journal of Mechanical Engineering 2012年第4期25卷 809-815页

作者： ZHANG Junhong LIU Hai BI Fengrong NI Guangjian ZHANG Guichang LIN jiewei YU Hanzhengnan State Key Laboratory of Engines Tianjin University Tianjin 300072 China

There are more researches on engine fan noise control focusing on reducing fan noise level through optimizing fan structure,and a lot of research achievements have been ***,researches on the effect of fan noise to engine noise quality are *** influences of the effects of fan structure optimization on the engine noise quality are ***,there will be a decline in fan noise level,but the deterioration of engine noise *** at the above problems,in consideration of fan structure design and engine noise quality,an innovative method to analyze the contribution of fan noise to engine noise quality using psychoacoustic theory is *** noises of diesel engine installing different cooling fans are measured by using the acoustic pressure *** experiment results are regarded as analysis *** model of sensory pleasantness is used to analyze the sound quality of a diesel engine with different cooling *** show that after installing 10-blade fan in medium diameter the sensory pleasantness at each test point is increased,and the increase is 13.53% on average,which indicate the improvement of the engine noise *** order to verify the psychoacoustical analysis,the subjective assessment is carried *** test result shows the noise quality of engine installed10-blade fan in medium diameter is most superior.1/3 octave frequency spectrum analysis is used to study the reason of the improvement of engine noise *** is found that after installing proper cooling fan the sound pressure level below 400 Hz are obviously increased,the frequency assignment and spectral envelope are more reasonable and a proper cooling fan can optimize the spectrum structure of the engine *** psychoacoustic study is applied in the contribution of fan noise to engine noise,and the idea of engine sound quality improvement through the structure optimization is proposed.

关键词： sound quality psychoacoustic engine noise fan noise

有晶状体眼后房型人工晶状体植入术中拱高与术后拱高的相关性研究

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中华眼外伤职业眼病杂志 2024年第4期46卷 289-296页

作者：张帅吴万民刘文洁畅颖杨李春樊泽琦刘杰为山西医科大学太原030001 山西医科大学附属山西省眼科医院白内障科太原030002

目的分析有晶状体眼后房型人工晶状体(pIOL)植入术中拱高与术后拱高的相关性。方法回顾性病例系列研究。纳入山西省眼科医院2022年1月至2022年3月接受V4c型可植入式接触镜(ICL)植入术的屈光不正者36例(67眼),使用术中OCT获得术中黏弹剂... 详细信息

目的分析有晶状体眼后房型人工晶状体(pIOL)植入术中拱高与术后拱高的相关性。方法回顾性病例系列研究。纳入山西省眼科医院2022年1月至2022年3月接受V4c型可植入式接触镜(ICL)植入术的屈光不正者36例(67眼),使用术中OCT获得术中黏弹剂去除前后的ICL拱高图像,术后用ImageJ进行分析处理,根据术中去除黏弹剂后的拱高分为3组:低拱高组(750μm)6眼,使用前节OCT测量术后1 d、1个月、3个月的ICL中央厚度及拱高,比较术中黏弹剂去除前后以及术后不同时间段的ICL拱高差异并分析术中与术后拱高的相关性。结果所有受术者术中黏弹剂去除前后以及术后1 d、1个月、3个月的拱高分别为(200.42±120.65)、432.00(310.00,581.00)、(592.99±202.62)、(535.75±158.35)、(509.66±157.92)μm,两两比较不同时间点的拱高差异均有统计学意义(均P<0.05),术后拱高有随时间下降趋势,且下降幅度逐渐减小,拱高逐渐趋于稳定。Spearman相关性分析显示术后不同时间的拱高均与前房深度、ICL型号、术中黏弹剂去除前、黏弹剂去除后的拱高呈正相关(均P<0.05)。术中前房黏弹剂去除前后的拱高相差为(254.13±185.96)μm,二者均与术后3个月的拱高线性相关,R^(2)分别为0.219、0.249(均P<0.001)。Kruskal-Wallis检验结果显示3组间术后1 d、1个月、3个月的拱高差异均有统计学意义(H=9.28、12.78、10.16,P=0.010、0.002、0.006),而前房深度、ICL型号差异无统计学意义(H=1.58、1.02,P=0.453、0.599)。在术后1个月、3个月时,低拱高组、正常拱高组均与高拱高组的术后拱高差异有统计学意义(均P<0.05),而术后1 d时,仅低拱高组与高拱高组的术后拱高差异有统计学意义(P=0.007)。结论PICL植入术后拱高会随时间下降,术中拱高对于预测术后拱高有指导价值,二者具有显著相关性,术中高拱高则术后拱高偏高。

关键词：有晶状体眼后房型人工晶状体相关性,拱高,术中,术后光学相干断层扫描

Unbalanced Load Simulation of Electronic Power Transformer in Distribution System

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Electricity 2006年第1期17卷 38-43页

作者： Wang Dan Mao Chengxiong Lu Jiming fan Shu Cao jiewei Wang Ben（Translated） Huazhong University of Science and Technology 不详

A control scheme of electronic power transformer (EPT) in a three-phase four-wire distribution system, which included an input section, an isolating section and an output section, was researched under unbalanced loads. The simple and appropriate control scheme was developed through analyzing the system requirements of the primary side and the load requirements of the secondary side. In the input section, a dual-loop control in synchronous rotating d-q coordinates was introduced, and in the output section, a dual-loop control based on instantaneous output voltage was used. Load characteristics of EPT were investigated by using Matlab/Simulink software. Simulation results showed that, with the proposed control scheme, the EPT has good performances and the sinusoidal input current and constant output voltage can be realized under both balanced and unbalanced loads.

关键词： electronic power transformer distribution system unbalanced load

An Analysis of Reliability and Competitiveness of a Corporation in China

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Systems Science and Systems Engineering 1996年第2期6卷 129-136页

作者： fan Jin(Yangzhou University, Yangrhou 225009, China)ZHANG jiewei(Dalian University of Technology, Dalian 116024, China)SHEN Ji(Yangzhou University, YangZhou 225009, Chian)

This paper, by using the theory of reliability, studies operating of a corporation in China. Firstly, the paper clarifies new characteristics of a corporation in China. Secondly, the paper analyses three kinds of systems that include series connection model, parellel connection model and mixed connection model. In the end, the paper studies four kinds of corporations and makes a forecast that are market-oriented corporation, innovation-oriented market, scale-oriented market and power-oriented market in China.

关键词： reliability corporation series connection parellel connection mixed connection market-oriented innovation-oriented scale-oriented power-oriented.