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The differentiability of solutions for elliptic equations which degenerate on part of the boundary of a convex domain

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Applied Mathematics(A Journal of Chinese Universities) 2018年第4期33卷 421-435页

作者： SONG jia-xin cao Yi Department of Mathematics and Information Science Shaanxi Normal University

In this paper,we study the differentiability of solutions on the boundary for equartions of type L;u=;u/x;+|x|;;u/y;=f（x,y）,where λ is an arbitrary positive number. By introducing a proper metric that is related to the elliptic operator L;, we prove the differentiability on the boundary when some well-posed boundary conditions are satisfied. The main difficulty is the construction of new barrier functions in this article.

关键词： elliptic equations convex domain differentiability

Characterization of polyoxometalates by electrospray ionization mass spectrometry

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Science China Chemistry 2015年第7期58卷 1206-1210页

作者： Qiaodi jia Yan Zhang Jie cao Key Laboratory of Cluster Science Ministry of Education of China Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials School of Chemistry Beijing Institute of Technology

The electrospray behaviors of saturated, substituted, and lacunary polyoxometalates （POMs） with classic Keggin and Dawson structures were investigated systematically by electrospray mass spectrometry （ESI-MS）. The anions included Keggin [SiW12O40]4-, [SiW11O39]8-, [SiW10O36]8 , [SiW9O34]10-, Dawson [P2W18O62]6-, [P2W17O61]10-, and metal-substituted Keggin derivatives such as [PW11MnO40]7-, [SiW10V2O40]6-, and [GeWgCu3O37]10-. Common species observed in the mass spectra arose from the protonation or cationization of either intact or dehydrated precursor ions. Compared to saturated and substituted POMs, lacunary POMs exhibited distinguished MS behaviors such as a much higher degree of cationization and dehydration of the bare polyoxoanions present in the mass spectra. In addition, some of these lacunary POMs were found to undergo subtle speciation change in solution. Freshly prepared solutions are suggested for synthetics for which lacunary POMs are starting materials. The advantages of the cation-exchange process which are prior to MS analysis are illustrated by an example.

关键词： saturated substituted and lacunary POMs electrospray ionization mass spectrometry cation-ion exchange process

Cascading failures in local-world evolving networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1336-1340页

作者： Zhe-jing BAO Yi-jia cao School of Electrical Engineering Zhejiang University Hangzhou 310027 China College of Electrical and Information Engineering Hunan University Changsha 410082 China

The local-world (LW) evolving network model shows a transition for the degree distribution between the exponential and power-law distributions, depending on the LW size. Cascading failures under intentional attacks in LW network models with different LW sizes were investigated using the cascading failures load model. We found that the LW size has a significant impact on the network's robustness against deliberate attacks. It is much easier to trigger cascading failures in LW evolving networks with a larger LW size. Therefore, to avoid cascading failures in real networks with local preferential attachment such as the Internet, the World Trade Web and the multi-agent system, the LW size should be as small as possible.

关键词： Complex network Local world (LW) Cascading failures Power-law Attack

OPTIMIZING DESIGN OF MECHANICAL SELF-CENTERING DEVICE FOR SUSPENSION HEIGHT

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Chinese Journal of Mechanical Engineering 2008年第6期21卷 69-75页

作者： cao min ZHANG Yongchao YU Fan School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China

Firstly, in view of the respective defects of existing self-centering devices for vehicle suspension height, the design scheme of the proposed mechanical self-centering device for suspension height is described. Taking the rear suspension of a certain light bus as a research example, the structures and parameters of the novel device are designed and ascertained. Then, the road excitation models, the performance evaluation indexes and the half-vehicle model are built, the simulation outputs of time and frequency domain are obtained with the road excitations of random and pulse by using MATLAB/Simulink software. So the main characteristics of the self-centering suspension are presented preliminarily. Finally, a multi-objective parameter design optimization model for the self-centering device is built by weighted sum approach, and optimal solution is obtained by adopting complex approach. The relevant choosing-type parameters for self-centering device components are deduced by using discrete variable optimal method, and the optimal results are verified and analyzed. So the performance potentials of the self-centering device are exerted fully in condition of ensuring overall suspension performances.

关键词： Suspension height Self-centering Vehicle height adjustment Optimizing design Multi-objective optimization

A Performance Driven Lot Merging Method with Closed Loop Optimization for Semiconductor Wafer Fabrication

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Chinese Journal of Electronics 2017年第5期26卷 912-918页

作者： cao Zhengcai HUANG Zhexiao LIU min College of Information Science and Technology Beijing University of Chemical Technology Symbolic Computation and Knowledge Engineering of ministry of Education Jilin University Department of Automation Tsinghua University

This paper deals with lot merging problem in semiconductor wafer fabrication *** is the possibility to merge two or more partial lots into single lot if their subsequent process routes are the same,an improved lot merging method is presented by grouping lots belonging to different *** on job information extracted from the buffers,several bin packing and knapsack solving algorithms are used to determine which lots should be *** iterative improvement procedure is introduced for optimizing merging strategy through a heuristic algorithm with resetting the ready time of critical *** closed loop structure with global revision factor is built for minimizing the impact of uncertain events while balancing the different orders processing *** to a simulation semiconductor manufacturing fab,the proposed algorithm can reduce cycle time and tardiness compared with other methods currently.

关键词： Semiconductor wafer fabrication Lot merging Simulation Bin packing

Structural design of organic battery electrode materials:from DFT to artificial intelligence

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Rare Metals 2023年第10期42卷 3269-3303页

作者： Ting-Ting Wu Gao-Le Dai Jin-jia Xu Fang cao Xiao-Hong Zhang Yu Zhao Yu-min Qian jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices Soochow UniversitySuzhou215123China College of Materials Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou311121China Department of Chemistry and Biochemistry University of Missouri–St.LouisSt.LouisMO63121USA Department of Health Technology Technical University of DenmarkKgs.Lyngby2800Denmark Key Lab of Advanced Optoelectronic Quantum Architecture and Measurement Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systemsand School of PhysicsBeijing Institute of TechnologyBeijing100081China

Redox-active organic materials are emerging as the new playground for the design of new exciting battery materials for rechargeable batteries because of the merits including structural diversity and tunable electrochemical properties that are not easily accessible for the inorganic *** importantly,the sustainability developed by using naturally abundant chemical elements(C,H,N,O and S) makes them as an ideal alternative material for Li-ion batteries(LIBs).However,the identification and screening of proper organic materials is still challenging in the past *** by the artificial intelligence,this review will give a summary of the theoretical design aspects of redox-active organic materials from densityfunctional theory(DFT) to machine learning(ML) methods in the past two decades,with a particular emphasis on the calculation method to predict the chemical/electrochemical stability and *** review will also analyze and discuss the challenges and perspectives for the development of organic battery materials.

关键词： Organic battery Density-functional theory(DFT) High-throughput computation Machine learning(ML)

Frozen Quantum Coherence for a Central Two-Qubit System in a Spin-Chain Environment

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Chinese Physics Letters 2018年第8期35卷 1-4页

作者： Yang Yang An-min Wang Lian-Zhen cao jia-Qiang Zhao Huai-Xin Lu 1Shandong Provincial Key Laboratory of Multi-Photon Entanglement and Manipulation Department of Physics and Optoelectronic EngineeringWeifang UniversityWeifang 261061 Department of Modern Physics University of Science and Technology of ChinaHefei 230026

We investigate the dynamics of coherence for a central two-qubit system coupled to an XY spin chain with the Dzyaloshinsky–Moriya interaction. It is found that a sudden transition of coherence exists near the critical point in the weak-coupling case, and an oscillatory envelope appears in the strong-coupling case. In both cases the freezing phenomenon of coherence can be found.

关键词： Frozen Quantum Coherence for a Central Two-Qubit System in a Spin-Chain Environment

A Method of Non-textured Regions Matching

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Chinese Journal of Electronics 2019年第3期28卷 598-603页

作者： jia Di ZHAO mingyuan cao Jun SONG Weidong School of Electronic and Information Engineering Liaoning Technical University School of Computing Informatics Decision System Engineering Arizona State University School of Geomatics Liaoning Technical University

It is difficult for existing dense or quasidense matching algorithms to obtain accurate matching results due to the lack of effective feature information in non-textured regions. This may affect the quality of subsequent 3 D reconstruction and super-resolution reconstruction. We propose a method of non-textured regions matching. To reduce the impact of noise and illumination, vector sampling normalized cross correlation is proposed to directly measure coherence between two colour images by the effective information of multi-channel features. Three mathematical properties are used in affine transformation: 1) Centroid location is not affected by affine transformation; 2) Affine transformation transforms a straight line into another straight line; 3) Affine transformation maintains the linear relation invariant. In non-textured regions, we can construct texture regions which have affine invariant properties to improve the accuracy of template matching. This could provide more information for the diffusion of dense or quasi-dense matching. In experiments, we demonstrate that the method has high accuracy in cases where there is no big distortion between the two viewing angles from two aspects of simulated images and photographic images.

关键词： Stereo matching Dense matching Nontextured region Affine transformation

Hand Vein Recognition Algorithm Based on NMF with Sparsity and Clustering Property Constraints in Feature Mapping Space

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Chinese Journal of Electronics 2019年第6期28卷 1184-1190页

作者： jia Xu SUN Fuming LI Haojie cao Yudong School of Electronics and Information Engineering Liaoning University of Technology School of Software Technology Dalian University of Technology

Most of the existed vein features are lack of robustness to light intensity variation, and some algorithms rely on the specified vein data sets, which leads to the limitation of real applications. To solve the problems,we propose a novel vein recognition algorithm based on Nonnegative matrix factorization(NMF) with double regularization terms. The innovations of our algorithm are mainly reflected in the following two aspects: in order to improve feature robustness, a novel feature mapping function is designed to map the initial Histogram of oriented gradient(HOG) feature to a new space; to enhance the recognition performance, an effective NMF model is presented, which not only reduces feature dimension, but also optimizes the feature sparsity and clustering property simultaneously. Experiments show that the proposed algorithm can achieve satisfactory results in terms of False rejection rate(FRR) and False acceptance rate(FAR), which indicates that our algorithm is valuable for other classification problems.

关键词： Vein recognition Nonnegative matrix factorization(NMF) Mapping function Feature sparsity