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Induced Subgraphs with Large Degrees at End-vertices for Hamiltonicity of Claw-free Graphs

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Acta Mathematica Sinica,English Series 2016年第7期32卷 845-855页

作者： Roman CADA Bin Long LI bo ning Sheng Gui ZHANG Department of Mathematics University of West Bohemia Centre of Excellence ITI - Institute for Theoretical Computer Science Charles University European Centre of Excellence NTIS - New Technologies for the Information Society P.O. Box 314 306 14 Pilsen Czech Republic Department of Applied Mathematics Northwestern Polytechnical University Xi'an 710072 P. R. China Center for Applied Mathematics Tianjin University Tianjin 300072 P. R. China

A graph is called claw-free if it contains no induced subgrapn lsomorpmc to K1,3. Matthews and Sumner proved that a 2-connected claw-free graph G is Hamiltonian if every vertex of it has degree at least （[V（G）I - 2）/3. At the workshop CSzC （Novy Smokovec, 1993）, Broersma conjectured the degree condition of this result can be restricted only to end-vertices of induced copies of N （the graph obtained from a triangle by adding three disjoint pendant edges）. Fujisawa and Yamashita showed that the degree condition of Matthews and Sumner can be restricted only to end-vertices of induced copies of Z1 （the graph obtained from a triangle by adding one pendant edge）. Our main result in this paper is a characterization of all graphs H such that a 2-connected claw-free graph G is Hamiltonian if eachend-vertex of every induced copy of H in G has degree at least IV（G）I/3 ＋ 1. This gives an affirmative solution of the conjecture of Broersma up to an additive ***-vertex of every induced copy of H in G has degree at least IV（G）I/3 ＋ 1. This gives an affirmative solution of the conjecture of Broersma up to an additive constant.

关键词： Induced subgraph large degree end-vertex claw-free graph Hamiltonian graph

Deformation bands in fully pearlitic steel during wire drawing

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Science China(Technological Sciences) 2014年第4期57卷 796-803页

作者： GUO ning SONG bo LUAN BaiFeng CHEN ZhiQian LIU Qing School of Materials Science and Engineering Southwest University School of Materials Science and Engineering Chongqing University

The deformation of fully pearlitic steels during wire drawing has been investigated for botb longitudinal section and transverse section by back-scattered electron imaging （BSEI）, electron back-scattered diffraction （EBSD）, and transmission electron mi- croscope （TEM）. The results show that a large number of deformation bands （DBs） composed of a mixture of kink-like bands and shear-like bands were observed both in the longitudinal section and the traverse section of the drawn wires. The formation of such bands involves two aspects： heterogeneous deformation in the scale of pearlite colonies and instability of fer- rite-cementite interfaces due to stress concentration during wire drawing. The development of suck bands in fully pearlitic steels dominates the formation of metallograpbic texture, reduces the pearlite interlamellar spacing and promotes the development of 〈 110〉 fiber crystalline texture of ferrite matrix during wire drawing.

关键词： pearlitic steel wire drawing deformation bands microstructure

Multiquadric Finite Difference (MQ-FD) Method and its Application

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Advances in Applied Mathematics and Mechanics 2009年第5期1卷 615-638页

作者： Yong Yuan Shan chang Shu ning Qin Department of Mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 119260Singapore Department of Mechanical Engineering University of SheffieldMappin StreetSheffield S13JDUnited Kingdom

The conventional finite difference(FD)schemes are based on the low order polynomial approximation in a local *** paper shows that when the polynomial approximation is replaced by the multiquadric(MQ)function approximation in the same region,a new FD method,which is termed as MQ-FD method in this work,can be *** paper gives analytical formulas of the MQ-FD method and carries out a performance study for its derivative approximation and solution of Poisson equation and the incompressible Navier-Stokes *** addition,the effect of the shape parameter c in MQ on the formulas of the MQFD method is *** approximation in one-dimensional space and Poisson equation in two-dimensional space are taken as model problems to study the accuracy of the MQ-FD ***,a lid-driven flow problem in a square cavity is simulated by the MQ-FD *** obtained results indicate that this method may solve the engineering problem very accurately with a proper choice of the shape parameter c.

关键词： MQ-FD method shape parameter central FD method

Metabolism of high density lipoproteins in liver cancer

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World Journal of Gastroenterology 2007年第23期13卷 3159-3163页

作者： Jing-Ting Jiang ning Xu chang-Ping Wu Department of Tumor Biological Treatment the Third Affiliated Hospital of Suzhou University Changzhou 213003 Jiangsu Province China Section of Clinical Chemistry & Pharmacology Lund University S-221 85 Lund Sweden

Liver plays a vital role in the production and catabolism of plasma lipoproteins. It depends on the integrity of cellular function of liver, which ensures homeostasis of lipid and lipoprotein metabolism. When liver ca... 详细信息

关键词： High density lipoproteins Metabolism Liver cancer

A wideband fast multipole boundary element method for half-space/plane-symmetric acoustic wave problems

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Acta Mechanica Sinica 2013年第2期29卷 219-232页

作者： chang-Jun Zheng Hai-bo Chen Lei-Lei Chen Department of Modern Mechanics University of Science and Technology of China

This paper presents a novel wideband fast multipole boundary element approach to 3D half-space/planesymmetric acoustic wave *** half-space fundamental solution is employed in the boundary integral equations so that the tree structure required in the fast multipole algorithm is constructed for the boundary elements in the real domain ***,a set of symmetric relations between the multipole expansion coefficients of the real and image domains are derived,and the half-space fundamental solution is modified for the purpose of applying such relations to avoid calculating,translating and saving the multipole/local expansion coefficients of the image *** wideband adaptive multilevel fast multipole algorithm associated with the iterative solver GMRES is employed so that the present method is accurate and efficient for both lowand high-frequency acoustic wave *** for exterior acoustic problems,the Burton-Miller method is adopted to tackle the fictitious eigenfrequency problem involved in the conventional boundary integral equation *** on the implementation of the present method are described,and numerical examples are given to demonstrate its accuracy and efficiency.

关键词： Helmholtz equation·boundary element method·Half-space/plane-symmetric problem·Wideband fast multipole method·Noise barrier

Positron Emission Tomography Lung Image Respiratory Motion Correcting with Equivariant Transformer

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Computers, Materials & Continua 2024年第5期79卷 3355-3372页

作者： Jianfeng He Haowei Ye Jie ning Hui Zhou bo She Faculty of Information Engineering and Automation Kunming University of Science and TechnologyYunnan Key Laboratory of Artificial IntelligenceKunming650500China School of Physics and Electronic Engineering Yuxi Normal UniversityYuxi653100China PET/CT Center Affiliated Hospital of Kunming University of Science and TechnologyFirst People’s Hospital of Yunnan ProvinceKunming650031China

In addressing the challenge of motion artifacts in Positron Emission Tomography (PET) lung scans, our studyintroduces the Triple Equivariant Motion Transformer (TEMT), an innovative, unsupervised, deep-learningbasedframework for efficient respiratory motion correction in PET imaging. Unlike traditional techniques,which segment PET data into bins throughout a respiratory cycle and often face issues such as inefficiency andoveremphasis on certain artifacts, TEMT employs Convolutional Neural Networks (CNNs) for effective featureextraction and motion ***’s unique approach involves transforming motion sequences into Liegroup domains to highlight fundamental motion patterns, coupled with employing competitive weighting forprecise target deformation field generation. Our empirical evaluations confirm TEMT’s superior performancein handling diverse PET lung datasets compared to existing image registration networks. Experimental resultsdemonstrate that TEMT achieved Dice indices of 91.40%, 85.41%, 79.78%, and 72.16% on simulated geometricphantom data, lung voxel phantom data, cardiopulmonary voxel phantom data, and clinical data, respectively. Tofacilitate further research and practical application, the TEMT framework, along with its implementation detailsand part of the simulation data, is made publicly accessible at https://***/yehaowei/temt.

关键词： PET lung scans respiratory motion correction triple equivariant motion transformer lie group motion decomposition

A novel simple bifunctional catalyst for the direct aldol reaction

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Chinese Chemical Letters 2011年第6期22卷 651-654页

作者： chang Lu Liu Hao Zhang ning Wang ab School of Chemistry and Chemical Engineering Southwest UniversityChongqing 400715China Department of Chemistry Sichuan University of Arts and SciencesDazhou 635000China

Direct aldol reactions of aldehydes and ketones can proceed smoothly in the presence of a catalytic amount of naphthol/sodium naphtholate（5 mol%） to afford the corresponding products with yields up to 98%.Such a bif... 详细信息

关键词： Aldol reactions Naphthol Sodium naphtholate Bifunctional catalyst Acid-base

Synthesis of highly active Cu(Ⅰ)-Y(Ⅲ)-Y zeolite and its selective adsorption desulfurization performance in presence of xylene isomers

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Petroleum Science 2021年第1期18卷 295-306页

作者： bo-Long Jiang Nan Jiang You-Xin chang Innovation Institute for Sustainable Maritime Architecture Research and Technology Qingdao University of TechnologyQingdao 266000China Chongqing changshou Sino French Water Co.Ltd. Chongqing 404100China

A bimetal-exchanged NaY zeolite(Cu(Ⅰ)-Y(Ⅲ)-Y)with a desirable adsorptive desulfurization(ADS)performance was prepared and characterized by means of X-ray diffraction,specific surface area measurements,X-ray fluorescence spectrometer,X-ray photoelectron spectroscopy,thermal gravity analysis and Fourier transform infrared *** effect of Y(Ⅲ)ions on ADS in the presence of the xylenes was *** indicated that the ADS performance of Y(Ⅲ)-Y is higher than that of most reported *** Y(Ⅲ)-based Cu(Ⅰ)-Y(Ⅲ)-Y demonstrated the higher breakthrough loading than those of reported Ce(Ⅲ)/Ce(Ⅳ)-based transition metal Y zeolites,showing that Y(Ⅲ)ions play a promoting role in improving the ADS *** Cu(Ⅰ)-Y(Ⅲ)-Y,a new strong S-M interaction(S stands for sulfur,while M stands for metal)active site was formed,which might be caused by the synergistic effect between Cu(Ⅰ)and Y(Ⅲ).The Cu(Ⅰ)-Y(Ⅲ)-Y,which combined the advantages of Cu(I)-Y and Y(Ⅲ)-Y,is a kind of promising *** breakthrough loading decreased in the order of Cu(Ⅰ)-Y(Ⅲ)-Y>Y(Ⅲ)-Y>Cu(Ⅰ)-Y,and the effect of xylene isomers on the sulfur removal was in the order of ortho-xylene>meta-xylene>para-xylene,which exhibited the same trend with the bond order of xylenes.

关键词： Desulfurization Yttrium Copper Y zeolite Competitive adsorption Xylenes

A Time-dependent Interaction Problem Between an Electromagnetic Field and an Elastic body

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Acta Mathematicae Applicatae Sinica 2020年第1期36卷 95-118页

作者： chang-kun WEI Jia-qing YANG bo ZHANG Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China

This paper considers the scattering of a time-dependent electromagnetic plane wave by a bounded elastic *** appropriate decomposition of the coupling interface conditions is proposed according to the Voigt’s model between the electromagnetic and elastic *** original unbounded scattering problem is equivalently reduced into an initial-boundary value problem in a bounded domain by introducing an exact transparent boundary condition(TBC)on a sufficiently large *** use of the Lax-Milgram lemma,the abstract inversion theorem of Laplace transform and the energy method,we verify the well-posedness and stability for the reduced ***,a priori estimates are established for the electromagnetic field and elastic displacement by taking special test functions directly in the time domain variational formulation.

关键词： electromagnetic elastic Laplace transform Lax-Milgram lemma energy method well-posedness