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Application of the improved dung beetle optimizer,muti-head attention and hybrid deep learning algorithms to groundwater depth prediction in the Ningxia area,China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 18-23页

作者： Jiarui Cai Bo Sun Huijun Wang Yi zheng Siyu Zhou Huixin Li Yanyan Huang Peishu Zong Collaborative Innovation Center on forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjingChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiChina China Meteorological Administration Key Laboratory of Transportation MeteorologyNanjingChina Jiangsu Meteorological Observatory NanjingChina

Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical *** learning can effectively solve this issue and has been proven useful in the prediction of groundwater depth in many *** this study,two new models are applied to the prediction of groundwater depth in the Ningxia area,*** two models combine the improved dung beetle optimizer(DBO)algorithm with two deep learning models:The Multi-head Attention-Convolution Neural Network-long Short Term Memory networks(MH-CNN-LSTM)and the Multi-head Attention-Convolution Neural Network-Gated Recurrent Unit(MH-CNN-GRU).The models with DBO show better prediction performance,with larger R(correlation coefficient),RPD(residual prediction deviation),and lower RMSE(root-mean-square error).Com-pared with the models with the original DBO,the R and RPD of models with the improved DBO increase by over 1.5%,and the RMSE decreases by over 1.8%,indicating better prediction *** addition,compared with the multiple linear regression model,a traditional statistical model,deep learning models have better prediction performance.

关键词： Groundwater depth Multi-head attention Improved dung beetle optimizer CNN-LSTM CNN-GRU Ningxia

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Carrier transport characteristics of H-terminated diamond films prepared using molecular hydrogen and atomic hydrogen

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International Journal of Minerals,Metallurgy and Materials 2017年第7期24卷 850-856页

作者： Jin-long Liu Liang-xian Chen Yu-ting zheng Jing-jing Wang Zhi-hong Feng Cheng-ming Li Institute for Advanced Materials and Technology University of Science and Technology Beijing Science and Technology on ASIC Laboratory Hebei Semiconductor Research Institute

The H-terminated diamond films, which exhibit high surface conductivity, have been used in high-frequency and high-power electronic devices. In this paper, the surface conductive channel on specimens from the same diamond film was obtained by hydrogen plasma treatment and by heating under a hydrogen atmosphere, respectively, and the surface carrier transport characteristics of both samples were compared and evaluated. The results show that the carrier mobility and carrier density of the sample treated by hydrogen plasma are 15 cm^2·V^（-1）·s^（-1） and greater than 5 × 1012 cm^（-2）, respectively, and that the carrier mobilities measured at five different areas are similar. Compared to the hydrogen-plasma-treated specimen, the thermally hydrogenated specimen exhibits a lower surface conductivity, a carrier density one order of magnitude lower, and a carrier mobility that varies from 2 to 33 cm^2·V^（-1）·s^（-1）. The activated hydrogen atoms restructure the diamond surface, remove the scratches, and passivate the surface states via the etching effect during the hydrogen plasma treatment process, which maintains a higher carrier density and a more stable carrier mobility.

关键词： H-termination diamond film surface conductivity carrier mobility plasma treatment

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Four-manifolds with positive isotropic curvature

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Frontiers of Mathematics in China 2016年第5期11卷 1123-1149页

作者： Bing-long CHEN xian-Tao HUANG School of Mathematics Sun Yat-sen University Guangzhou 510275 China Yau Mathematical Sciences Center Tsinghua University Beijing 100084 China

We give a survey on 4-dimensional manifolds with positive isotropic curvature. We will introduce the work of B. L. Chen, S. H. Tang and X. P. Zhu on a complete classification theorem on compact four-manifolds with positive isotropic curvature （PIC）. Then we review an application of the classification theorem, which is from Chen and Zhu＇s work. Finally, we discuss our recent result on the path-connectedness of the moduli spaces of Riemannian metrics with positive isotropic curvature.

关键词： Four-manifolds positive isotropic curvature (PIC) Ricci flow

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Neural Dynamics for Distributed Collaborative Control of Manipulators With Time Delays

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IEEE/CAA Journal of Automatica Sinica 2022年第5期9卷 854-863页

作者： long Jin Xin zheng Xin Luo School of Information Science and Engineering Lanzhou UniversityLanzhou 730000 IEEE State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China School of Computer Science and Technology Chongqing University of Posts and TelecommunicationsChongqing 400065 Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

Time-delay phenomena extensively exist in practical systems,e.g.,multi-agent systems,bringing negative impacts on their *** work analyzes a collaborative control problem of redundant manipulators with time delays and proposes a time-delayed and distributed neural dynamics *** assumptions that the network topology is fixed and connected and the existing maximal time delay is no more than a threshold value,it is proved that all manipulators in the distributed network are able to reach a desired *** proposed distributed scheme with time delays considered is converted into a time-variant optimization problem,and a neural dynamics solver is designed to solve it ***,the proposed neural dynamics solver is proved to be stable,convergent and ***,the allowable threshold value of time delay that ensures the proposed scheme’s stability is *** examples and comparisons are provided to intuitively prove the validity of the proposed neural dynamics scheme and solver.

关键词： Distributed collaborative control neural dynamics redundancy resolution repetitive motion planning(RMP) time delay

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Inversion for atmosphere duct parameters using real radar sea clutter

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Chinese Physics B 2012年第2期21卷 618-623页

作者： Sheng zheng Fang Han-xian Institute of Meteorology PLA University of Science and TechnologyNanjing 211101China Sate Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China

This paper addresses the problem of estimating the lower atmospheric refractivity （M profile） under nonstandard propagation conditions frequently encountered in low altitude maritime radar applications. The vertical structure of the refractive environment is modeled using five parameters and the horizontal structure is modeled using five parameters. The refractivity model is implemented with and without a priori constraint on the duct strength as might be derived from soundings or numerical weather-prediction models. An electromagnetic propagation model maps the refractivity structure into a replica field. Replica fields are compared with the observed clutter using a squared-error objective function. A global search for the 10 environmental parameters is performed using genetic algorithms. The inversion algorithm is implemented on the basis of S-band radar sea-clutter data from Wallops Island, Virginia （SPANDAR）. Reference data are from range-dependent refractivity profiles obtained with a helicopter. The inversion is assessed （i） by comparing the propagation predicted from the radar-inferred refractivity profiles with that from the helicopter profiles, （ii） by comparing the refractivity parameters from the helicopter soundings with those estimated. This technique could provide near-real-time estimation of ducting effects.

关键词： atmosphere duct radar clutter refractivity from clutter genetic algorithm

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Nonparametric M-estimation for Functional Stationary Ergodic Data

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 491-512页

作者： xian-zhu XIONG zheng-yan LIN College of Mathematics and Computer Science Fuzhou UniversityFuzhou 350108China Department of Mathematics Zhejiang UniversityHangzhou 310027China

This paper considers a nonparametric M-estimator of a regression function for functional stationary ergodic *** precisely,in the ergodic data setting,we consider the regression of a real random variable Y over an explanatory random variable X taking values in some semi-metric abstract *** some mild conditions,the weak consistency and the asymptotic normality of the M-estimator are ***,a simulated example is provided to examine the finite sample performance of the M-estimator.

关键词： nonparametric M-estimator functional stationary ergodic data weak consistency asymptotic normality

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Quantum secure direct dialogue using Einstein-Podolsky-Rosen pairs

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1238-1243页

作者： zheng Chao long GuoFei State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua University Tsinghua National Laboratory for Information Science and Technology Department of Physics Shandong University Department of Physics Loughborough University

A two-step quantum secure direct dialogue protocol using Einstein-Podolsky-Rosen(EPR)pair block is *** the protocol,the dialogue messages are encoded on series of qubits and sent through a quantum channel *** security of the protocol is assured by its connection to the two-step quantum secure direct communication protocol,which has been proved *** protocol has several *** is a direct communication protocol that does not require a separate classical communication for the *** has high capacity as two bits of secret messages can be transmitted by an EPR *** a dialogue protocol,the two parties can speak to each other either simultaneously or sequentially.

关键词： quantum communication QSDC QSDD EPR pairs

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Strain-induced Precipitation Behavior ofδPhase in Inconel 718 Alloy

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Journal of Iron and Steel Research International 2014年第3期21卷 375-381页

作者： xian-ping WEI Wen-jie zheng Zhi-gang SONG Ting LEI Qi-long YONG Qing-cheng XIE Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Central Iron and Steel Research Institute No.704 Institute of China Shipbuilding Industry Corporation

To study the precipitation dynamics of 3 phase in Inconel 718 alloy, two-stage interrupted compression method was used in the region of cold deformation temperatures and the temperatures range from 875 to 975 ℃. The precipitation-time-temperature （PTT） curve of 3 phase was obtained by analyzing the softening kinetics curves. For verifying the type of the precipitates and confirming the validity of the test, the transmission electron microscopy （TEM）, scanning transmission electron microscopy （STEM） and energy dispersion spectrum （EDS） were em- ployed. Experimental results indicated that the PTT curve for 3 precipitation exhibited a typical ＂C＂ shape and the nose points of start and finish precipitation were about 5 s at 920 ℃ and 2 815 s at 940 ℃, respectively. In addition, the nucleation of δ was heterogeneous. The nucleation sites varied with temperatures, including dislocation, grain boundary and stacking fault within γ″ phase. And 3 particles grew quickly at higher temperature with lower density. Moreover, the driving force of nucleation was mainly including chemical free energy, interracial energy and disloca- tion distorted energy. And the dislocation distorted energy could decide the density of nucleation in the strain-induced process.

关键词： Inconel 718 alloy strain-induced precipitation cold deformation nucleation site

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Elemental Partitioning Characteristics of Equilibrium Phases in Inconel 718 Alloy at 600-1100℃

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Journal of Iron and Steel Research International 2013年第6期20卷 88-94页

作者： WEI xian-ping zheng Wen-jie SONG Zhi-gang LEI Ting YONG Qi-long XIE Qing-cheng Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Central Iron and Steel Research Institute No.704 Institute of China Shipbuilding Industry Corporation

The optimization of heat treatment and chemical composition for Inconel 718 alloy has been investigated uninterruptedly because of its excellent mechanical properties and metallurgical *** species , chemical compositions and content of equilibrium phases of Inconel 718alloy in the temperature range of 600-1 100℃ were calculated by using thermodynamic software ＂ Thermo-Calc ＂ and the latest relevant datebase of Ni-base superalloys.A concept of elemental partitioning fraction was used to study the partitioning characteristics of alloying elements in each equilibrium phase at different temperatures , such as Ni , Cr , Fe , Nb , Mo , Al , Ti and C , and some calculation results were confirmed under a scanning transmission electron microscope （ STEM ） .The results showed that the elemental partitioning characteristics with the change of temperature revealed the selective partitioning characteristic of alloying elements in equilibrium phases at different temperatures , such as Nb was mainly distributed in δ and γ′phase , C in carbides , Al and Ti in γ′phase and Cr , Mo in Laves *** the same time , the effect of the change of component and quantity for each precipitated phase on matrix phase can be helpfully understood , which provided a theoretic foundation to optimize the chemical composition and heat treatment in different environments for Inconel 718alloy.

关键词： Inconel 718alloy Thermo-Calc thermodynamic calculation elemental partitioning fraction

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Effects of Carbon Content on Mechanical Properties of Inconel 718 Alloy

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Journal of Iron and Steel Research International 2015年第1期22卷 78-83页

作者： Wen-jie zheng xian-ping WEI Zhi-gang SONG Qi-long YONG Han FENG Qing-cheng XIE Central Iron and Steel Research Institute Materials Research Center Dong Fang Steam Turbine Works No.704 Institute of China Shipbuilding Industry Corporation

For improving the service performance of Inconel 718 alloy, especially used as a corrosion-resistant alloy for special environment, the microstructure and mechanical property of different carbon-containing Inconel 718 alloys were investigated by the Thermo-Calc software and experiments. The experimental results indicated that the mor- phology, distribution and types of carbides mainly existing in the form of MC＇were hardly influenced by solution treatment at 1050 ℃ for 1 h. The precipitation amount and particle size of carbides decreased with the decrease of carbon content, which was the main reason resulting in the increase of ductility and toughness. In addition, moving dislocation could be restrained by the precipitation of carbides. Therefore, the strength could benefit from the precip- itation strengthening of carbides when the precipitation of γ′/γ″ phase was not influenced by the precipitation of carbides.

关键词： Inconel 718 alloy microstructure carbide mechanical property precipitation strengthening

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