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Journal of Analysis and Testing 2024年第1期8卷 40-51页

作者： Xianfen Zhang Wenxian Wang Lijiao Guan huajie chen Dai Li Lipeng Zhang Saipeng Huang School of Chemical Engineering Northwest UniversityXi'an 710069China Chemical Technology Academy of Shandong Province Qingdao University of Science and TechnologyJinan250014China

Trace ferric ion(Fe^(3+))detection has attracted increasing attention as an essential and indispensable role in many physiological and pathological *** green-emitting carbon quantum dots(Green-CQDs)were obtained through a green and facile one-step hydrothermal method for the specific recognition and trace detection of Fe^(3+)in this *** optimal excitation and emission wavelengths of the CQDs were 395 nm and 490 nm,*** stokes shift was up to 95 nm,which can effectively reduce the background fluorescence *** addition,it also exhibited good water solubility,stability,and high *** fluorescence intensity of Green-CQDs was linearly related to the concentration of Fe^(3+)(range of 0-80μmol/L),and the detection limit was as low as 59 nmol/*** good properties were favorable and successful for Fe^(3+)detection in tap water,human serum samples and living *** addition,a fluorescence visual test paper(FP@CQDs)was prepared utilizing filter paper as carrier,which can quickly identify Fe^(3+)in real time,and is suitable for the visualization analysis of Fe^(3+)in *** an efficient nanoprobe,the Green-CQDs held great promise and bright prospects in practical application in prevention and early clinical diagnosis of Fe^(3+)-associated diseases.

关键词： Carbon quantum dots Fluorescent Hydrothermal Fe^(3+)-specific detection Cell imaging

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遥感图像小样本舰船识别跨域迁移学习算法

遥感学报 2024年第3期28卷 793-804页

作者：陈华杰吕丹妮周枭刘俊杭州电子科技大学通信信息传输与融合技术国防重点学科实验室杭州310018

跨域迁移学习旨在利用现有公开数据集,突破源域和目标域样本类别空间须一致的约束,提升目标域样本的识别精度。针对现有跨域迁移学习算法应用于遥感图像小样本舰船目标识别时存在的迁移类别受限和负迁移问题,本文提出一种基于源域样本... 详细信息

跨域迁移学习旨在利用现有公开数据集,突破源域和目标域样本类别空间须一致的约束,提升目标域样本的识别精度。针对现有跨域迁移学习算法应用于遥感图像小样本舰船目标识别时存在的迁移类别受限和负迁移问题,本文提出一种基于源域样本相关性排序的跨域迁移学习算法:首先将目标域样本逆向加入源域分类任务中,根据加入前后各类别源域样本的识别精度变化情况,对源域样本进行相关性排序,将其划分为强/弱/负相关样本;然后采取自监督联合学习策略,在目标域分类网络中引入自监督角度预测辅助分支,筛选出的强相关源域样本仅参与该辅助分支的训练,不改变目标域主分类网络的结构。算法通过相关性排序去除了弱/负相关源域样本,有效避免了负迁移;引入自监督角度预测辅助分支,在保持主分类网络结构完整性的同时,充分利用了强相关源域样本的有效信息,学习到更具泛化能力的目标特征。实验结果显示:在遥感舰船小样本目标数据集上,提出的算法优于跨域迁移学习中广泛使用的Fine-tune (微调)算法;与仅使用主分类网络的目标域识别算法相比,遥感舰船目标识别精度提升了17.59%。

关键词：遥感舰船识别小样本学习跨域迁移学习相关性排序自监督学习

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基于深度学习的舰船目标重识别技术

指挥控制与仿真 2024年第4期46卷 88-96页

作者：莫倩倩刘俊管坚杨麒霖彭冬亮陈华杰谷雨杭州电子科技大学浙江杭州310018

面向行人和车辆的重识别技术已在情报分析领域得到成功应用,但是对于舰船目标的重识别技术研究还比较缺乏,对此本文提出了一种基于双重特征融合的海上去雾重识别网络,用于海面舰船目标的情报分析和监管。首先,为了降低负样本对特征的影... 详细信息

面向行人和车辆的重识别技术已在情报分析领域得到成功应用,但是对于舰船目标的重识别技术研究还比较缺乏,对此本文提出了一种基于双重特征融合的海上去雾重识别网络,用于海面舰船目标的情报分析和监管。首先,为了降低负样本对特征的影响,采用了视角辅助的自适应查询扩展方法和基于相似度的特征融合方法。其次,在重识别分支的浅层嵌入了去雾分支,利用权重共享技术提取无雾特征,并通过上采样技术和金字塔模型重建去雾图像,以增强网络在低能见度场景下的识别能力。最后,提出了一种基于伪交并比的非极大值抑制方法,通过修正检测框置信度来提高船舶目标的检测精度。实验结果表明,所提方法的性能优于现有方法,并且各模块对网络性能都有贡献。

关键词：船舶重识别深度学习卷积神经网络视角辅助

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Defect-modulated and heteroatom-functionalized Ti_(3−x)C_(2)T_(y)MXene 3D nanocavities induce growth of MoSe_(2)nanoflakes toward electrocatalytic hydrogen evolution in all pH electrolytes

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Nano Research 2024年第7期17卷 6294-6304页

作者： Ming Du Xianzhi Yang Jian Zhang Wei chen huajie Huang Xinbao Zhu Xing’ao Li State Key Laboratory for Organic Electronics and Information Displays and Institute of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Centre for Advanced Materials(SICAM)Nanjing University of Posts and Telecommunications(NJUPT)Nanjing 210023China College of Electronic and Optical Engineering and College of Flexible Electronics Nanjing University of Posts and Telecommunications(NJUPT) Nanjing 210023China New Energy Technology Engineering Lab of Jiangsu Province College of ScienceNanjing University of Posts and Telecommunications(NJUPT)Nanjing 210023China College of Pharmaceutical and Chemical Engineering Taizhou UniversityJiaojiang 318000China College of Mechanics and Materials Hohai UniversityNanjing 210098China College of Chemical Engineering Nanjing Forestry UniversityNanjing 210037China

Reducing kinetic energy barriers and developing accessible active sites are critical to deliver high hydrogen evolution reaction(HER)*** this paper,we synthesized defect-modulated and heteroatom(boron)-functionalized three-dimensional(3D)bowl-shaped Ti_(3−x)C_(2)T_(y)MXene(B-TCT)nanocavities coupled with the vertical growth of MoSe_(2)*** B-TCT@MoSe_(2)nanohybrids catalyst delivers the overpotentials of 49.9,52.7,and 67.8 mV to reach a HER current density of 10 mA·cm^(−2)under acidic,alkaline,and neutral conditions,*** outstanding HER activity is predominantly attributed to the heteroatom functionalization,self-adapting Ti vacancy(VTi)defect modulation,and spatial configuration design in the 3D B-TCT nanocavity,which synergistically regulate the electronic structure,activate the basal plane/edge unsaturated sites,and reduce the reaction energy *** and theoretical calculations demonstrate that strong heterogeneous interfacial bonding interactions between B-TCT and MoSe_(2)can dramatically reduce the free energy of hydrogen adsorption and facilitate efficient interfacial charge migration,thus essentially improving the HER *** used this 3D porous nanohybrid system assembled by defectrich lamellar structures to elucidate the advantageous synergistic effects of multiple mechanisms among defect structure,heteroatom functionalization,and interfacial coupling,which provided important insights for the development of efficient hybridtype catalysts.

关键词： electrocatalytic H_(2)evolution three-dimensional(3D)MXene nanocavity MoSe_(2)nanoflake self-adapting Ti vacancy defect heteroatom-functionalized interfacial interaction

Error Estimates of Some Numerical Atomic Orbitals in Molecular Simulations

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Communications in Computational Physics 2015年第6期18卷 125-146页

作者： huajie chen Reinhold Schneider Zentrum Mathematik Technische Universitat MunchenBoltzmannstraße 385747 GarchingGermany Institut fur Mathematik Technische Universitat BerlinStraße des 17.Juni 136D-10623 BerlinGermany

Numerical atomic orbitals have been successfully used in molecular simulations as a basis set,which provides a nature,physical description of the electronic states and is suitable for ■(N)calculations based on the strictly localized *** paper presents a numerical analysis for some simplified atomic orbitals,with polynomial-type and confined Hydrogen-like radial basis functions *** give some a priori error estimates to understand why numerical atomic orbitals are computationally efficient in electronic structure calculations.

关键词： Kohn-Sham density functional theory numerical atomic orbitals Slater-type orbitals a priori error estimate

A TWO-SCALE HIGHER-ORDER FINITE ELEMENT DISCRETIZATION FOR SCHRDINGER EQUATION

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Journal of Computational Mathematics 2009年第2期27卷 315-337页

作者： huajie chen Fang Liu Aihui Zhou LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China Graduate University of Chinese Academy of Sciences Beijing 100190 China School of Applied Mathematics Central University of Finance and Economics Beijing 100081 China

In this paper, a two-scale higher-order finite element discretization scheme is proposed and analyzed for a Schroedinger equation on tensor product domains. With the scheme, the solution of the eigenvalue problem on a fine grid can be reduced to an eigenvalue problem on a much coarser grid together with some eigenvalue problems on partially fine grids. It is shown theoretically and numerically that the proposed two-scale higher-order scheme not only significantly reduces the number of degrees of freedom but also produces very accurate approximations.

关键词： Higher-order Finite element Discretization Eigenvalue Schroedinger equation Two-scale

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利用局部特征匹配的运动小目标光流估计

电光与控制 2024年第2期31卷 98-104页

作者：陈华杰许琮擎周枭占俊杰杭州电子科技大学自动化学院杭州310000

基于深度光流估计的动态背景运动小目标检测,为了保证小目标的检测性能,一般采用较少的下采样次数以维持较高的分辨率,但由此带来了较大的计算耗时。特征匹配是深度光流估计的一个核心处理环节,其耗时在光流估计整体耗时中的占比较大,... 详细信息

基于深度光流估计的动态背景运动小目标检测,为了保证小目标的检测性能,一般采用较少的下采样次数以维持较高的分辨率,但由此带来了较大的计算耗时。特征匹配是深度光流估计的一个核心处理环节,其耗时在光流估计整体耗时中的占比较大,且对下采样次数非常敏感。据此,提出一种基于局部特征匹配的快速光流估计算法:引入目标运动信息,缩小特征匹配的空间范围,减少待处理的数据量;设计分块局部匹配策略,引入批处理机制,避免出现逐点局部匹配策略数据处理耗时过大问题,实现算法加速。在此基础上,在光流估计获取的光流场上,采用CenterNet网络检测运动目标对应的光流异常区域。从光流估计耗时、检测精度等方面开展了实验验证,结果表明:针对运动小目标检测,分块特征匹配光流估计比全局特征匹配光流估计耗时减少约25%,目标检测性能相当。

关键词：运动小目标动态背景光流估计局部特征匹配光流异常区域检测

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Orbital-Free Density Functional Theory for Molecular Structure Calculations

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Numerical Mathematics(Theory,Methods and Applications) 2008年第1期1卷 1-28页

作者： huajie chen Aihui Zhou LSEC Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Graduate University of Chinese Academy of Sciences Beijing 100080 China

We give here an overview of the orbital-free density functional theory that is used for modeling atoms and *** review typical approximations to the kinetic energy,exchange-correlation corrections to the kinetic and Hartree energies, and constructions of the *** discuss numerical discretizations for the orbital-free methods and include several numerical results for illustrations.

关键词：密度功能理论分子结构数值离散化轨道函数

Adaptive Finite Element Approximations for a Class of Nonlinear Eigenvalue Problems in Quantum Physics

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Advances in Applied Mathematics and Mechanics 2011年第4期3卷 493-518页

作者： huajie chen Xingao Gong Lianhua He Aihui Zhou LSEC Institute of Computational Mathematics and Scientific/Engineering ComputingAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Physics Fudan UniversityShanghai 200433China

In this paper,we study an adaptive finite element method for a class of nonlinear eigenvalue problems resulting from quantum physics that may have a nonconvex energy *** prove the convergence of adaptive finite element approximations and present several numerical examples of micro-structure of matter calculations that support our theory.

关键词： Adaptive finite element convergence micro-structure nonlinear eigenvalue

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基于深度强化学习的多目标跟踪技术研究

无线电通信技术 2024年第1期50卷 187-192页

作者：杨麒霖刘俊管坚莫倩倩陈华杰谷雨石义芳杭州电子科技大学通信信息传输与融合技术国防重点学科实验室浙江杭州310018

在随机有限集多目标跟踪过程中,由于跟踪问题的复杂性,会耗费大量的计算成本,特别是在目标和杂波密集的复杂情况中,计算成本呈指数增长。随机有限集中通常采用的分配算法——例如Murty算法的时间复杂度为滤波器生成的代价矩阵规模的三... 详细信息

在随机有限集多目标跟踪过程中,由于跟踪问题的复杂性,会耗费大量的计算成本,特别是在目标和杂波密集的复杂情况中,计算成本呈指数增长。随机有限集中通常采用的分配算法——例如Murty算法的时间复杂度为滤波器生成的代价矩阵规模的三次方。为了减少跟踪耗时,结合组合优化的思想,将代价矩阵重定义为二分图,采用了一种基于深度强化学习的二分图匹配算法,取代传统随机有限集中的分配算法,并通过仿真实验验证了所提方法的可行性。实验表明,所提方法在保证跟踪性能的前提下减少了跟踪耗时,提升了跟踪实时性。

关键词：随机有限集强化学习组合优化

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