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On a General Class of Semiparametric Hazards Regression Models for Recurrent Gap Times

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Acta Mathematicae Applicatae Sinica 2019年第3期35卷 549-563页

作者： qin JIANG hui ZHAO Hong qin Department of Statistics Central China Normal UniversityWuhan 430079China Department of Mathematics Huanggang Normal UniversityHuanggang 438000China Department of Statistics Zhongnan University of Economics and LawWuhan 430073China

In the article,we investigate a general class of semiparametric hazards regression models for recurrent gap *** general class includes the proportional hazards model,the accelerated failure time model and the accelerated hazards models as special *** model is flexible in modelling recurrent gap times since a covariate effect is identified as having two separate components,namely a time-scale change on hazard progression and a relative hazards *** order to infer the model parameters,the procedure is proposed based on estimating *** asymptotic properties of the proposed estimators are established and the finite sample properties are investigated via simulation *** addition,a lack of fit test is presented to assess the adequacy of the model and an application of data from a bladder cancer study is reported for illustration.

关键词： gap times model checking recurrent events estimating equations semiparametric model

Research hotspots and trends in Chinese minority traditional medicine during 2021:a visual bibliometrics analysis

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Traditional Medicine Research 2022年第3期7卷 113-123页

作者： Shao-hui Wang Jing qin xian-Li Meng Yi Zhang School of Ethnic Medicine Chengdu University of Traditional Chinese MedicineChengdu 611137China Medical College of qingdao Binhai University Affiliated Hospital of Qingdao Binhai University/Qingdao Military-Civilian Integration HospitalQingdao 266555China State Key Laboratory of Southwestern Chinese Medicine Resources Innovative Institute of Chinese Medicine and PharmacyChengdu University of Traditional Chinese MedicineChengdu 611137China

Background:Chinese minority traditional medicine(CMTM)is an important component of Chinese traditional culture and medicine that has contributed to the health and prosperity of Chinese people of all ethnic *** this type of medicine has attracted interest,its developmental trends and research status remain ***,we used literature metrology to evaluate the publications on CMTM during 2021 and explore hotspots and frontier ***:Reports associated with CMTM published between January 1,2021,and December 31,2021,were downloaded from the Web of Science *** authors,institutions,countries,journals,keywords,and other standard bibliometric indicators were analyzed and visualized using CiteSpace,and research hotspots and trends were ***:We retrieved 152 CMTM-related publications,among which Tibetan medicine attracted the most *** covering alternative and complementary medicine topics were the most prevalent sources of reports about CMTM,particularly the Journal of *** research in this field was conducted in China and frequently published by traditional Chinese medicine colleges and *** author,Yi Zhang,has extensively investigated Tibetan and Korean *** keyword co-occurrence network revealed that investigations into ethnic groups mainly focused on the pharmacological activities and phytochemical components of ethnic *** keywords of gut microbiota and autophagy in some publications reflect the direction of future CMTM ***:Our findings showed the current status and trends in CMTM *** information will help identify new research directions and hotspots in this field.

关键词： Chinese minority traditional medicine bibliometrics CiteSpace Web of Science Tibetan medicine Mongolian medicine

GPS: graph contrastive learning via multi-scale augmented views from adversarial pooling

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Science China(Information Sciences) 2025年第1期 145-158页

作者： Wei JU Yiyang GU Zhengyang MAO Ziyue QIAO Yifang qin Xiao LUO hui XIONG Ming ZHANG School of Computer Science National Key Laboratory for Multimedia Information ProcessingPeking University Artificial Intelligence Thrust The Hong Kong University of Science and Technology Department of Computer Science University of California

Self-supervised graph representation learning has recently shown considerable promise in a range of fields, including bioinformatics and social networks. A large number of graph contrastive learning approaches have shown promising performance for representation learning on graphs, which train models by maximizing agreement between original graphs and their augmented views(i.e., positive views). Unfortunately, these methods usually involve pre-defined augmentation strategies based on the knowledge of human experts. Moreover, these strategies may fail to generate challenging positive views to provide sufficient supervision signals. In this paper, we present a novel approach named graph pooling contrast(GPS) to address these *** by the fact that graph pooling can adaptively coarsen the graph with the removal of redundancy, we rethink graph pooling and leverage it to automatically generate multi-scale positive views with varying emphasis on providing challenging positives and preserving semantics, i.e., strongly-augmented view and weakly-augmented view. Then, we incorporate both views into a joint contrastive learning framework with similarity learning and consistency learning, where our pooling module is adversarially trained with respect to the encoder for adversarial robustness. Experiments on twelve datasets on both graph classification and transfer learning tasks verify the superiority of the proposed method over its counterparts.

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Synthesis and Characterization of Novel N-Ferrocenesulfonyl Benzimidazole

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Chinese Chemical Letters 2003年第9期14卷 901-903页

作者： Bing qin YANG, Peng hui YANG, Ai Lin ZHU Department of Chemistry, Northwest University, xian 710069 Department of Chemistry Northwest University Xian 710069

A new series of ferrocenesulfonyl benzimidazle has been synthesized and characterized by 1H NMR, FT-IR and elemental analysis. They are expected to have special bio-activity.

关键词： N-Ferrocenesulfonyl benzimidazole synthesis characterization.

Characteristics of alumina particles in dispersion-strengthened copper alloys

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International Journal of Minerals,Metallurgy and Materials 2014年第11期21卷 1115-1119页

作者： Xue-hui Zhang Xiao-xian Li School of Materials Science and Engineering Jiangxi University of Science and Technology School of Metallurgical and Chemical Engineering Jiangxi University of Science and Technology

Two types of alumina dispersion-strengthened copper（ADSC） alloys were fabricated by a novel in-situ reactive synthesis（IRS） and a traditional internal oxidation（IO） process. The features of alumina dispersoids in these ADSC alloys were investigated by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. It is found that nano-sized γ-Al2O3 particles of approximately 10 nm in diameter are homogeneously distributed in the IRS-ADSC composites. Meanwhile, larger-sized, mixed crystal structure alumina with rod-shaped morphology is embedded in the IO-ADSC alloy. The IRS-ADSC composites can obtain better mechanical and physical properties than the IO-ADSC composites; the tensile strength of the IRS-ADSC alloy can reach 570 MPa at room temperature, its electrical conductivity is 85% IACS, and the Rockwell hardness can reach 86 HRB.

关键词： metallic matrix composites alumina copper in-situ reactive synthesis internal oxidation

SOME PROBLEMS WITH THE METHOD OF FUNDAMENTAL SOLUTION USING RADIAL BASIS FUNCTIONS

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Acta Mechanica Solida Sinica 2007年第1期20卷 21-29页

作者： Wang hui qin qinghua College of Civil Engineering and Architecture Henan University of Technology Zhengzhou 450052 China Department of Mechanics Tianjin University Tianjin 300072 China Department of Engineering Australian National University Canberra ACT 0200 Austrulia

The present work describes the application of the method of fundamental solutions （MFS） along with the analog equation method （AEM） and radial basis function （RBF） approximation for solving the 2D isotropic and anisotropic Helmholtz problems with different wave numbers. The AEM is used to convert the original governing equation into the classical Poisson＇s equation, and the MFS and RBF approximations are used to derive the homogeneous and particular solutions, respectively. Finally, the satisfaction of the solution consisting of the homogeneous and particular parts to the related governing equation and boundary conditions can produce a system of linear equations, which can be solved with the singular value decomposition （SVD） technique. In the computation, such crucial factors related to the MFS-RBF as the location of the virtual boundary, the differential and integrating strategies, and the variation of shape parameters in multi-quadric （MQ） are fully analyzed to provide useful reference.

关键词： meshless method analog equation method method of fundamental solution radial basis function singular value decomposition Helmholtz equation

Surface morphology and crystal orientation of electrodeposited tungsten coatings with different pulse parameters

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Rare Metals 2018年第5期37卷 407-412页

作者： xian-qin Fang Ying Zhang Kai-Gui Zhu Wen-Jia Han Jian-Gang Yu Zhe Chen hui-Jun Shi Beijing Key Laboratory of Advanced Nuclear Energy Materials and Physics School of Physics and Nuclear Energy EngineeringBeihang University

This study was conducted to investigate the influence of pulse parameters on the surface morphology and crystal orientation of the tungsten coatings electrodeposited on pure copper substrates. The deposited coatings were analyzed by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and energy-dispersive spectrometer （EDS）. SEM analysis indicates that pulse parameters have significant influences on the surface morphology of the deposited coatings. Meanwhile, the change in grain size of the tungsten coatings demonstrates that the change in frequency and duty cycle could cause the variation of nucleation rate and grain growth of deposits. Moreover, no obvious diffusion layer at the coating/substrate interface is found by line analysis of EDS. XRD results reveal that tungsten coatings are of bcc structure and the preferred orientation of the deposits varies with duty cycle and period.

关键词： Tungsten coating Electrodeposition Pulse parameters Crystal orientation Surface morphology

Transport of Propylene Carbonate-LiTFSI Electrolytes in P(VDF-HFP)Using Time-resolved ATR-FTIR Spectroscopy:Diffusion Coefficients and Molecular Interactions

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Chinese Journal of Polymer Science 2021年第8期39卷 975-983,I0005页

作者： hui-xian Li Lei Hou Pei-Yi Wu National Engineering Research Center for Dyeing and Finishing of Textiles College of ChemistryChemical Engineering and BiotechnologyDonghua UniversityShanghai 201620China

The time-resolved attenuated total reflectance-Fourier transform infrared(ATR-FTIR)spectroscopy is employed to investigate the transport mechanism of gel electrolytes by monitoring the diffusion behavior of propylene carbonate-lithium bis(trifluoromethylsulfonyl)imide(PC-LiTFSI)solution through poly(vinylidene fluoride-co-hexafluoropropylene)(P(VDF-HFP))*** behavior has been observed for both TFSr and *** temperature leads to faster diffusion of TFSI'and PC,which could be related to the increased free volume in P(VDF-HFP)matrix and rapid molecular movements upon *** molecular interactions among LiTFSI,PC and P(VDF-HFP)have been *** the diffusion process,PC molecules,in the form of small clusters,can firstly diffuse through the P(VDF-HFP)film and interact with P(VDF-HFP)by dipole-dipole interaction,acting as the ***,Li+diffuses into P(VDF-HFP)with the help of ion-dipole interactions between Li+and C=0 of ***,TFSI-diffuses through the polymer matrix in solvation *** addition,slight ion-dipole interactions between Li+and P(VDF-HFP)have been observed as *** in this work contribute to a better understanding of transport process in gel polymer electrolytes for lithium-ion batteries and support the development of improved gel polymer electrolytes by rationally regulating molecular interactions.

关键词： ATR-FTIR spectroscopy Gel polymer electrolyte Transport mechanism Molecular interaction Diffusion coefficient

Mechanism of ferrite nucleation induced by Y_(2)O_(2)S inclusion in low carbon steel

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Journal of Iron and Steel Research International 2023年第6期30卷 1291-1299页

作者： Hai-hui Zhang hui-hui Xiong Jing qin Jian-bo Zhang Faculty of Materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou 341000JiangxiChina National Rare Earth Functional Material Innovation Center Ganzhou 341000JiangxiChina

To reveal the mechanism of ferrite nucleation induced by Y_(2)O_(2)S inclusion in steel,the work of adhesion,interfacial energy,structure stability and electronic properties of Fe(111)/YY_(2)O_(2)S(001)interfaces with various terminations were first investigated using the first-principles ***,the steels with and without yttrium were prepared,while the rare earth yttrium-based inclusions in low carbon steel were characterized using an electron probe micro-analyzer,and the grain size of steel was analyzed using a scanning electron microscope with electron backscattered *** results show that the bonding strength of Fe/Y_(2)O_(2)S interfaces with S-and Y-terminations is stronger than that of the interface with *** Fe-hcp-S interfaces with S-termination have the highest work of adhesion(4.01 J/m2)and the lowest interface distance(1.323A).The Fe-hcp-S interface exhibits the highest stability,and its interfacial bonding force is mainly attributed to the strong hybridization of Fe-3d and S-2p orbitals in the energy range of-7.5-0 ***,the interfacial energy of Fe-hcp-S is substantially lower than those of the ferrite(s)/Fe(L)interface and the ferrite-austenite interface,suggesting that Y_(2)O_(2)S inclusions in steel can efficiently promote ferrite *** experimental observations demonstrate that the ferrite grain size of steel containing 0.03 wt.% Y is much more refined than that of the steel without yttrium,and the average grain size of steel with and without Y is 102 and 258μm,*** indicates that the results of our calculations match with experimental findings.

关键词： Ferrite nucleation Inclusion Interfacial energy First-principles calculation Refinement