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Evaluating the hydrological effects of the Three Gorges Reservoir based on a large-scale coupled hydrological-hydrodynamic-dam operation model

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Journal of Geographical Sciences 2023年第5期33卷 999-1022页

作者： ZENG Sidong LIU Xin- XIA Jun DU Hong chen minghao HUANG Renyong Chongqing Institute of Green and Intelligent Technology CASChongqing400714China Chongqing School University of Chinese Academy of SciencesChongqing400714China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China College of Resources and Environmental Science South-Central Minzu UniversityWuhan430074China Yangtze River Scientific Research Institute Wuhan430010China

Understanding the hydrological effects of the Three Gorges Dam operation in the entire reservoir area is significant to achieving optimal dam regulation. In this paper, a large-scale coupled hydrological-hydrodynamic-dam operation model is developed to comprehensively evaluate the hydrological effects of the river-type Three Gorges Reservoir. The results show that the coupled model is effective for hydrological, hydrodynamic regime and hydropower simulations in the reservoir area. Dam operation could have a notable positive effect on flood control and could reduce the maximum daily flood peak by up to 26.2%. It also contributes a large amount of hydropower, approximately 94.27 TWh/year, and a water supply increase for the downstream area of up to 22% during the dry season. In the flood season, the water level at Cuntan would increase under the condition that the water level of the dam is higher than approximately 158 m due to dam operation. In the dry season, attention should be paid to the low flow velocity near the dam in the reservoir area.

关键词： hydrological effects Three Gorges Reservoir coupled model flood control

Homogenous metallic deposition regulated by abundant lithiophilic sites in nickel/cobalt oxides nanoneedle arrays for lithium metal batteries

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Journal of Energy Chemistry 2023年第2期77卷 11-18,I0001页

作者： Fenqiang Luo Dawei Xu Yongchao Liao minghao chen Shuirong Li Dechao Wang Zhifeng Zheng Fujian Provincial Industry Technologies Development Base for New Energy Fujian Provincial Engineering and Research Center of Clean and High-valued Technologies for BiomassXiamen Key Laboratory for High-valued Conversion Technology of Agricultural BiomassCollege of EnergyXiamen UniversityXiamen 361102FujianChina China Fujian Innovation Laboratory of Energy Materials Science and Technology(Tan Kah Kee Innovation Laboratory) Xiamen 361102FujianChina

Although lithium(Li)metal delivers the highest theoretical capacity as a battery anode,its high reactivity can generate Li dendrites and"dead"Li during cycling,resulting in poor reversibility and low Li *** uniform Li plating/stripping is the core of solving these ***,we design a highly lithiophilic carbon film with an outer sheath of the nanoneedle arrays to induce homogeneous Li plating/*** excellent conductivity and 3D framework of the carbon film not only offer fast charge transport across the entire electrode but also mitigate the volume change of Li metal during *** abundant lithiophilic sites ensure stable Li plating/stripping,thereby inhibiting the Li dendritic growth and"dead"Li *** resulting composite anode allows for stable Li stripping/plating under 0.5 mA cm^(-2) with a capacity of 0.5 mA h cm^(-2) for 4000 h and 3 mA cm^(-2) with a capacity of3 mA h cm^(-2) for 1000 *** Ex-SEM analysis reveals that lithiophilic property is different at the bottom,top,or channel in the structu re,which can regulate a bottom-up uniform Li deposition *** cells paired with LFP show a stable capacity of 155 mA h g^(-1) under a current density of *** pouch cell can keep powering light-emitting diode even under 180°bending,suggesting its good flexibility and great practical applications.

关键词： Nickel/cobalt oxides Nanoneedle arrays Lithiophilic sites Lithium metal batteries

Inverting the rock mass P-wave velocity field ahead of deep buried tunnel face while borehole drilling

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International Journal of Mining Science and Technology 2024年第5期34卷 681-697页

作者： Liu Liu Shaojun Li Minzong Zheng Dong Wang minghao chen Junbo Zhou Tingzhou Yan Zhenming Shi State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China China Railway Eryuan Engineering Group CO. LTD.Chengdu 610031China Department of Hydraulic and Hydropower Engineering Tsinghua UniversityBeijing 100084China Hubei Communications Planning and Design Institute CO. LTD.Wuhan 430051China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China

Imaging the wave velocity field surrounding a borehole while drilling is a promising and urgently needed approach for extending the exploration range of the borehole *** paper develops a drilling process detection(DPD)system consisting of a multifunctional sensor and a pilot geophone installed at the top of the drilling rod,geophones at the tunnel face,a laser rangefinder,and an onsite computer.A weighted adjoint-state first arrival travel time tomography method is used to invert the P-wave velocity field of rock mass while borehole drilling.A field experiment in the ongoing construction of a deep buried tunnel in southwestern China demonstrated the DPD system and the tomography ***-frequency analysis of typical borehole drilling detection data shows that the impact drilling source is a pulse-like seismic exploration wavelet.A velocity field of the rock mass in a triangular area defined by the borehole trajectory and geophone receiving line can be *** the borehole core and optical image validate the inverted P-wave velocity field.A numerical simulation of a checkerboard benchmark model is used to test the tomography *** rapid convergence of the misfits and consistent agreement between the inverted and observed travel times validate the P-wave velocity imaging.

关键词： Deep buried tunnel Wave velocity field Borehole drilling Tomography Rock mass

A Method for Implementing Multi-Joint Coordination in Hybrid Articulated Manipulator Design

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A Method for Implementing Multi-Joint Coordination in Hybrid...

基于双层深度强化学习的园区综合能源系统多时间尺度优化管理

第43届中国控制会议

作者： Yinghua Cao Mingrui Luo minghao chen En Li Gang chen Rui Guo Institute of Automation Chinese Academy of Sciences The School of Artifcial Intelligence University of Chinese Academy of Sciences Jiaxing University State Grid Shandong Electric Power Company

The cable-driven segmented manipulator, drawing inspiration from the undulating movements of snakes,is renowned for its exceptional flexibility and adaptability, rendering it highly suitable for deployment in intricate and confined spaces. However, challenges arise in scenarios involving a multitude of joints, encompassing an excessive number of driving motors, elevated manufacturing costs, and heightened control complexity. To address these challenges, our proposed approach focuses on achieving flexible coordination among multiple joints in the design of a hybrid manipulator. The method enables isometric rotation among a variable number of adjacent links by adjusting the configuration of synchronous wheels. This design approach allows the flexible configuration of joint sets in cable-driven segmented manipulators to adapt to various working environments. The proposed design method was employed to fabricate prototypes of two-joint and three-joint linked manipulators. Kinematic equations were formulated considering the unique characteristics of linked joints. Following assembly and control system design, experiments validated the method's effectiveness. This innovative approach streamlines multi-joint hybrid manipulator structures, reducing manufacturing costs.

关键词： Multi-Joint linkage Hybrid manipulator Synchronous wheel

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电工技术学报 2023年第7期38卷 1864-1881页

作者：陈明昊孙毅谢志远华北电力大学电气与电子工程学院北京102206 华北电力大学(保定)电气与电子工程学院保定071000

园区综合能源系统(PIES)的能源转换结构复杂性、新能源出力与多能负荷的不确定性以及不同能源系统管理时间尺度的差异性,是阻碍PIES实现高效管理与经济效益优化的主要原因。该文提出了一种基于双层深度强化学习的园区综合能源系统多时... 详细信息

园区综合能源系统(PIES)的能源转换结构复杂性、新能源出力与多能负荷的不确定性以及不同能源系统管理时间尺度的差异性,是阻碍PIES实现高效管理与经济效益优化的主要原因。该文提出了一种基于双层深度强化学习的园区综合能源系统多时间尺度优化管理方法。该方法面向包含燃气、热力、电力三种能源的园区综合能源系统模型,构建上、下两层深度确定性策略梯度(DDPG)管理模型,分别以0.5h和5min为长短时间尺度滚动制定燃气与热力系统、电力系统的管理方案。仿真结果表明,所提方法不仅能有效克服深度强化学习算法在训练过程中出现“维数灾难”情况,还能以差异化时间尺度滚动制定PIES的不同能源系统管理方案,并优化其总体经济效益。

关键词：综合能源系统深度强化学习深度确定性策略梯度(DDPG) 经济效益储能管理

A Monocular Pose Estimation Network for Slender Tubular Train Couplers

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A Monocular Pose Estimation Network for Slender Tubular Trai...

第43届中国控制会议

作者： Ao Zhang minghao chen Dejie Luan Guodong Yang En Li Institute of Automation Chinese Academy of Sciences The School of Artificial Intelligence University of Chinese Academy of Sciences The School of Automation and Intelligence Beijing Jiaotong University

Pose estimation of train couplers is a crucial task for the train uncoupling robot. Existing pose estimation methods are commonly employed for extracting convex-shaped objects;however, their applicability is limited when dealing with the slender tubular geometry characteristic of train couplers. To address this issue, we propose a novel method for estimating the pose of train couplers directly from RGB images. Our method utilizes a robust backbone composed of pure convolution modules to effectively capture essential geometric features from monocular images. We also incorporate dynamic snake convolution into the network to specifically focus on the slender tubular structural feature of the train coupler. Finally, a novel adaptive weighted pose loss function is proposed to further improve the precision of the train coupler pose. Experimental results on our custom coupler dataset and the Linemod dataset demonstrate significant improvements achieved by our proposed method.

关键词： Pose estimation Monocular vision Train coupler Dynamic snake convolution

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多源模糊信息系统中的属性约简

华南理工大学学报（自然科学版） 2020年第12期48卷 144-152页

作者：李蒙蒙庞晋中陈明浩哈尔滨工业大学数学学院黑龙江哈尔滨150001 大连理工大学数学科学学院辽宁大连116024

人们从多个渠道得到大量的模糊信息,将这些信息进行融合以得到更加精确的信息就变得尤为重要。文中首先利用条件熵构造了多源模糊信息系统的融合模型,此模型通过利用新的条件熵将多个模糊信息系统最终融合成一个模糊信息表;然后利用任... 详细信息

人们从多个渠道得到大量的模糊信息,将这些信息进行融合以得到更加精确的信息就变得尤为重要。文中首先利用条件熵构造了多源模糊信息系统的融合模型,此模型通过利用新的条件熵将多个模糊信息系统最终融合成一个模糊信息表;然后利用任意两个模糊集合之间的贴进度来构造两个模糊关系之间的相似度,建立了3种模糊关系相似度。此外,基于多源模糊信息系统融合后的模糊信息表,根据3种模糊关系相似度来对融合后的模糊信息表进行属性约简,进而实现多源模糊信息系统的属性约简;最后通过实验验证了所分析与设计模型的正确性和有效性。结果表明,文中提出的多源模糊信息系统的约简方法在处理模糊数据方面具有一定的价值,丰富了知识发现的理论基础。

关键词：属性约简模糊信息系统多源信息融合粗糙集

使用time-lapse筛选早期IVF/ICSI胚胎及其临床结局

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南方医科大学学报 2015年第12期35卷 1760-1764,1781页

作者：陈明颢黄军钟影全松南方医科大学南方医院妇产科生殖医学中心广东广州510515 成都市锦江区妇幼保健院生殖医学中心四川成都610016

目的通过比较使用time-lapse（延迟摄像）和传统形态学方法筛选IVF/ICSI胚胎的临床结局,评价time-lapse用于早期胚胎观察和筛选的价值。方法回顾性分析139个IVF/ICSI周期的资料,根据胚胎的筛选方法,分为time-lapse monitoring组（TLM组... 详细信息

目的通过比较使用time-lapse（延迟摄像）和传统形态学方法筛选IVF/ICSI胚胎的临床结局,评价time-lapse用于早期胚胎观察和筛选的价值。方法回顾性分析139个IVF/ICSI周期的资料,根据胚胎的筛选方法,分为time-lapse monitoring组（TLM组）（n=68）和对照组（n=71）,比较两组间的βHCG阳性率、临床妊娠率和胚胎着床率,并根据女方年龄、受精方式进行亚组分析。结果 TLM组的βHCG阳性率、临床妊娠率、胚胎着床率分别为：66.2%、61.8%、47.1%;对照组的βHCG阳性率、临床妊娠率、胚胎着床率分别为：47.9%、43.7%、30.3%;TLM组的βHCG阳性率、临床妊娠率、胚胎着床率均高于对照组,且差异均有统计学意义（P〈0.05）。亚组分析显示：相较于年龄≤30岁的患者,年龄31~35岁的患者利用time-lapse更能明显改善临床结局;利用time-lapse能明显提高IVF周期的βHCG阳性率、临床妊娠率、胚胎着床率,但对于ICSI和TESA周期,效果则不理想。结论使用time-lapse动态监测胚胎并根据胚胎的形态动力学参数对胚胎进行评价和筛选,与传统方法相比,能获得更好的临床结局;年龄较大的（〉30岁）或者是进行IVF周期的患者更能从中获益。

关键词： time-lapse 传统形态学方法胚胎筛选临床妊娠率胚胎着床率

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开放式电源模块损耗及散热的分析与优化

南京航空航天大学学报 2014年第4期46卷 544-551页

作者：陈明浩陈乾宏任小永杨鸣强南京航空航天大学江苏省新能源发电与电能变换重点实验室南京210016

开放式电源模块作为模块电源的一个发展方向,其PCB铜层不仅作为导电线路,同时承担散热器作用.本文基于有源箝位正激拓扑,完善了开放式电源模块的损耗模型分析,给出磁件铁损和线路损耗的精确计算,引入随负载变化的温度系数,实现了全负载... 详细信息

开放式电源模块作为模块电源的一个发展方向,其PCB铜层不仅作为导电线路,同时承担散热器作用.本文基于有源箝位正激拓扑,完善了开放式电源模块的损耗模型分析,给出磁件铁损和线路损耗的精确计算,引入随负载变化的温度系数,实现了全负载范围内对损耗特性的准确预计.在精确建模的基础上,综合考虑满载效率、空载损耗及散热要求,给出模块电源优化的系统思路,并结合18～36 V输入、5 V/150W输出的指标,给出了开关频率、同步整流管并联只数、PCB铜厚影响的定量分析和具体优化方法.此外,结合损耗分析,通过对温升的估算给出过孔、敷铜面积、PCB层数的散热分析与优化设计.最后,样机实验验证了理论分析的正确性.

关键词：模块电源开放式损耗优化散热分析系统思路