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Effect of Reclamation on the Groundwater-Lake Water Interaction in chen Lake

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Journal of Earth Science 2024年第3期35卷 1083-1086页

作者： Kun Lei Teng Ma Liuzhu chen Zhenxing Li Yu chen School of Environmental Studies State Key Laboratory of Biogeology and Environmental GeologyChina University of GeosciencesWuhan 430078China

0 INTRODUCTION To relieve the short supply of suitable land for residing,cultivating,and commerce,it is accepted to reclaim land from lakes,river estuaries,and coastal regions in many countries(Mancini et al.,2020).The large-scale reclamation activities have an irreversible effect on the mico-geomorphology and hydrodynamic system of seasonally flooded areas(Zhang et al.,2019;Yu et al.,2018).For example,coastal regions reclaimed extended the groundwater flow paths,as well as created groundwater level rise,resulting in water-logging in the reclaimed area(Hu et al.,2008).Similar changes in groundwater flow systems may alter groundwater-lake water interactions,and it can ultimately affect the water cycle in the lake ***,such detailed studies are presently *** addition,natural exchanges between the lake and groundwater systems can be strongly affected by physical hydrological processes(Javadzadeh et al.,2020),chemical properties(Kamtchueng et al.,2015),and bioto behavior(Hancock et al.,2005).

关键词： groundwater coastal logging

尼罗罗非鱼(Oreochromis nilotica Linn)幼鱼渗透压调节的初步研究

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中国海洋大学学报（自然科学版） 1989年第S2期27卷 88-98页

作者：叶畹初陈大刚马琳青岛海洋大学海洋渔业系

作者提出了放置于水温为19～20℃及30℃,盐度为0,16‰和30‰的各水体中尼罗罗非鱼渗透压调节的时间过程。研究揭示出尼罗罗非鱼幼鱼具有极其灵活的渗透压调节能力力:当水体由于盐度的改变,其冰点下降值Δ°改变114～121.4％时,幼鱼在收... 详细信息

作者提出了放置于水温为19～20℃及30℃,盐度为0,16‰和30‰的各水体中尼罗罗非鱼渗透压调节的时间过程。研究揭示出尼罗罗非鱼幼鱼具有极其灵活的渗透压调节能力力:当水体由于盐度的改变,其冰点下降值Δ°改变114～121.4％时,幼鱼在收容五天后,血液渗透压重新达到平衡,冰点下降值Δ°只增加1.6～4.7％,当水体的Δ°改变292～307.2％,幼鱼血液渗透压的Δ°值只增加4.7～6.2％。作者认为,该幼鱼渗透压的调节过程分为三个阶段,一、失控期,Δ°值迅速增加二,调节期,Δ°缓慢地随收容时间继续增加,直达到最大值,并开始下降;三、趋平期,幼鱼血液的Δ°值下降并达到平衡位置。尼罗罗非鱼渗透压调节的具体时间过程及特点取决于其内外渗透浓度变化的梯度(从淡水到海水或半海水)以及水温、饵料条件。

关键词：尼罗罗非鱼渗透压鳃泌氯细胞

铜催化二氧化碳参与的芳基烯烃不对称硼羧化反应

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有机化学 2024年第3期44卷 1038-1040页

作者：贵永远陈小旺余达刚四川师范大学化学与材料科学学院成都610068 四川大学化学学学院绿色化学与技术教育部重点实验室成都610064

α-手性羧酸在药物、农药、调料及保健品等领域中具有十分广泛的应用.目前工业上合成α-手性羧酸类化合物的主要方法是不饱和酸的不对称氢化反应,其存在原料较难获得、使用贵金属催化剂以及难以构建α-手性季碳羧酸等局限.因此,基于廉... 详细信息

α-手性羧酸在药物、农药、调料及保健品等领域中具有十分广泛的应用.目前工业上合成α-手性羧酸类化合物的主要方法是不饱和酸的不对称氢化反应,其存在原料较难获得、使用贵金属催化剂以及难以构建α-手性季碳羧酸等局限.因此,基于廉价易得工业原料的精准高效转化,发展温和条件下高效高选择性地构建α-手性羧酸的新方法,一直是合成化学家们关注的焦点.另一方面,二氧化碳(CO_(2))作为一种储量丰富、廉价易得、无毒且可再生的C1资源,其高效利用对于推动可持续发展具有重要意义.

关键词：贵金属催化剂手性季碳二氧化碳不饱和酸温和条件羧化反应高选择性铜催化

Meridional deflection of global eddy propagation derived from tandem altimetry: Mechanism and implication

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Science China Earth Sciences 2024年第3期67卷 811-825页

作者： Ge chen Xiaoyan chen Frontiers Science Center for Deep Ocean Multispheres and Earth System School of Marine TechnologyOcean University of ChinaQindao 266100China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQindao 266237China

A common view on meridional deflection of eddy propagation is poleward for cyclones and equatorward for anticyclones. This widely accepted polarity-sensitive pattern has been increasingly undermined given that it is systematically violated on both zonal and regional scales as recently reported. Here, we approach the problem by exploring these violations in terms of eddy effects of spatiotemporal geostrophy, thermal fading, and flow dragging, yielding the following main conclusions.(1) The polarity-dependent deflection discrepancy is a pseudo feature resulting from a biased fit to the normalized eddy tracks which are spatially asymmetric(though azimuthally symmetric) between the two signs;Instead, the primary pattern of eddy deflection appears to be geographically correlated and polarity independent.(2) Geostrophic adjustment plays a critical role in defining the meridional movement of an eddy. Specifically, a consistent poleward(equatorward) trajectory bending of spatially(temporally) ageostrophic eddies is observed irrespective of their polarity.(3) The mechanism of eddy deflection is also determined by its zonal propagation direction. Westward propagating eddies are substantially affected by thermal fading, while opposite ones by flow dragging. A realistic and comprehensive understanding of eddy deflection mechanisms serves as a significant contribution to the prediction of eddy trajectory, and the protection of ocean environment.

关键词： Mesoscale eddies Eddy propagation Eddy meridional deflection Satellite observation Geostrophic adjustment

A refined representation method of the particle size distribution curve based on grading entropy

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Particuology 2024年第5期88卷 302-311页

作者： Xing Li Qun chen Zhaozhao Liu cheng Zhou chen Wang chen chen State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China

The particle size distribution(PSD)curve is an important expression of the basic properties of the *** characteristic parameters such as median particle size D_(50),effective particle size D_(10),and some combinations of characteristic parameters can only represent some points of the PSD curve,failing to represent all information of the PSD *** this paper,a fraction characteristic parameter F that could reflect the fraction size variation of the PSD curve was introduced based on grading *** a new presentation method of the A-B-F three parameters was proposed for a refined representation of the PSD *** was found that the newly constructed model not only better represents the differences in the width of PSD curves but also has a higher sensitivity than the A-B two-parameter model proposed by Lő*** PSD curves with similar distributions,the new presentation method has a higher degree of discrimination than that of the D_(50)-C_(u)-C_(c) three-parameter or the four-parameter combination G_(c) proposed by ***,the application of this new method in describing the spatial nonuniformity distribution of depositions and predicting the soil hydraulic conductivity was *** research results can provide a reference for the refined representation of PSD curves.

关键词： Grading entropy Particle size distribution curve Refined representation

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自适应噪声消除技术与计算机模拟

铁道学报 1988年第2期 22-28页

作者：周大纲陈寒达上海铁道学院

本文从维纳滤波角度简述自适应滤波器及自适应噪声消除的基本原理。在微机上实现对实际语音的自适应消噪处理,其结果为进一步研制实用的自适应消噪器打下了基础。

关键词：计算机模拟自适应噪声消除算法计算机仿真维纳滤波器线性滤波器自适应滤波器自适应噪声抵消器自适应消噪 LMS

嵌入式控制器模块中VME总线接口电路的设计

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测控技术 2000年第4期19卷 31-33页

作者：陈大港李旭陈光 (成都)电子科技大学CAT室 610054

以VXI总线规范为依据 ,并结合国内外最新的工控PC和IC技术 ,详细介绍了一种VME总线接口电路的实现方法 ,对国产VXI总线仪器系统嵌入式控制器命令模块的研制成功具有一定的参考价值。

关键词： VXI总线 VME总线嵌入式控制器模块接口电路

Track correlation algorithm based on CNN-LSTM for swarm targets

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Journal of Systems Engineering and Electronics 2024年第2期35卷 417-429页

作者： chen Jinyang WANG Xuhua chen Xian Research Institute for National Defense Engineering Academy of Military SciencesLuoyang 471023China Information Engineering University Zhengzhou 450001China School of Computer Science and Technology Xidian UniversityXi’an 710071China

The rapid development of unmanned aerial vehicle(UAV) swarm, a new type of aerial threat target, has brought great pressure to the air defense early warning system. At present, most of the track correlation algorithms only use part of the target location, speed, and other information for *** this paper, the artificial neural network method is used to establish the corresponding intelligent track correlation model and method according to the characteristics of swarm ***, a route correlation method based on convolutional neural networks (CNN) and long short-term memory (LSTM)Neural network is designed. In this model, the CNN is used to extract the formation characteristics of UAV swarm and the spatial position characteristics of single UAV track in the formation,while the LSTM is used to extract the time characteristics of UAV swarm. Experimental results show that compared with the traditional algorithms, the algorithm based on CNN-LSTM neural network can make full use of multiple feature information of the target, and has better robustness and accuracy for swarm targets.

关键词： track correlation correlation accuracy rate swarm target convolutional neural network(CNN) long short-term memory(LSTM)neural network

Two-stage Planning Method for Energy Router Considering Its Optimal Operation in Distribution Networks

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 605-616页

作者： Meifu chen Mingchao Xia Qifang chen School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China

An energy router can effectively optimize the network loss and power quality of distribution networks. The optimal configuration of the energy router is relatively complex because issues dynamically influence each other, such as the location of the energy router, optimal number and capacity of its ports, and building new distribution lines for the ports. Presently, there has been very few research studies on the practical problems for the energy router. In this paper, a planning model of an energy router combined with the distribution network is established, which fully exploits the active and reactive power control abilities of the energy router to optimize the operation of the grid. The configuration problem is decoupled into two stages. The upper layer determines the location of the energy router and the parameters of the candidate new distribution lines for the ports. The lower layer calculates the optimal configuration of the energy router by minimizing the total annual cost. Because of the same rated bus voltage in the distribution network, the existing structure of the energy router is changed to be more applicable for the distribution network, and then the power flow model of the energy router is also modified. Due to the nonlinearity of the model, the planning model is converted into a mixed-integer second-order cone model to solve efficiently. In addition, some core factors influencing the optimal scheme of the energy router are also analyzed in this paper. Simulation results show that the optimal scheme of the energy router can significantly improve the economic deployment of the energy router, and optimize the network loss and power quality of the distribution network.

关键词： Capacity allocation distribution network energy router optimal operation