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Proof of Ding’s Conjecture on Maximal Stable Sets and Maximal Cliques in Planar Graphs

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Acta Mathematicae Applicatae Sinica 2010年第3期26卷 473-480页

作者： Jing Sun zhi-quan Hu Faculty of Mathematics and Statistics Central China Normal University Wuhan 430079 China School of Mathematics and quantitative Economics Hubei University of Education Wuhan 430205 China

X. Deng et al. proved Chvātal＇s conjecture on maximal stable sets and maximal cliques in graphs. G. Ding made a conjecture to generalize Chvátal＇s conjecture. The purpose of this paper is to prove this conjecture ... 详细信息

关键词： Maximal stable set maximal clique planar graph

Representing Topological Relationships Among Heterogeneous Geometry- Collection Features

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Journal of Computer Science & Technology 2004年第3期19卷 280-289页

作者： zhi-NongZhong NingJing LuoChen qiu-YunWu SchoolofElectronicScienceandEngineering NationalUniversityofDefenseTechnologyChangsha310073P.R.China

Topological relationships between two spatial features represent important knowledge in Geographical Information Systems (GIS). In the last few years, many models that represent topological relationships have been proposed. But these models cannot represent the topological relationships between heterogeneous geometrycollection features, which are composed of different dimensional geometries. In this paper, the formal definition of regular heterogeneous geometrycollection and regularization rules are given. Based on the spatial model, two methods for representing topological relationships between these complex features are proposed. The first method is Dimensionally Extended Nine-Intersection Model Based on Components (DE-9IMBC) that extends Dimensionally Extended Nine-Intersection Model (DE-9IM) and takes into account the topological relationships between components of these complex features. The advantage of DE-9IMBC is that a large number of different topological relationships can be checked. The second method extends the definitions of topological relationships in Open Geodata Interoperability Specification (OpenGIS), and redefines the seven named topological relationships:{Disjoint, Touches, Within, Crosses, Overlaps, Contains and Equal}, to represent the topological relationships between heterogeneous geometrycollection features. It is proven that the seven extended topological relationships are complete and mutually exclusive, and they are suitable for being embedded in spatial query languages.

关键词： GIS 拓扑关系几何聚集关系矩阵地理信息系统

Study of semileptonic decay of Bs^-0→φI^+I^- in QCD sum rule

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Communications in Theoretical Physics 2020年第9期72卷 58-69页

作者： Ying-quan Peng Mao-zhi Yang School of Physics Nankai UniversityTianjin 300071China

In this work we study the semileptonic decay of Bs^-0→φI^+I^-(l=e,μ,τ) with the QCD sum rule method. We calculate the Bs^-0→φ ftranslation form factors relevant to this semileptonic decay, then the branching ratios of Bs^-0→φI^+I^-(l=e,μ,τ)decays are calculated with the form factors obtained here. Our result for the branching ratio of Bs^-0→φμ^+μ^- agree very well with the recent experimental data. For the unmeasured decay modes such as Bs^-0→φe^+e^- and Bs^-0→τ^+τ……-, we give theoretical predictions.

关键词： semileptonic decay form factor QCD sum rule

Optimal Design of Co/In/Cu Sputtering Target Assembly Using Finite Element Method and Taguchi Method

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Acta Metallurgica Sinica(English Letters) 2019年第11期32卷 1407-1414页

作者： Lin Jiang Liang Zhang zhi-quan Liu Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 11016China School of Mechatronic Engineering Jiangsu Normal UniversityXuzhou 221116China

Target assembly is a key consumable material for producing thin fi lm used in the electronic packaging and devices. The residual stresses induced during the process of soldering are detrimental to the performance of target assembly. In this work, the intensity and distribution of the soldering residual stress of Co/In/Cu target assembly subjected to a 20 W/(m^2 K) cooling condition corresponding to the actual air cooling process were studied, based on fi nite element simulation and Taguchi method, to optimize the sputtering target assembly. Effects of different control factors, including solder material, thickness of solder layer, target and backing plate, on the soldering residual stress of target assembly are investigated. The maximum residual stress is calculated as 9.28 MPa in the target located at 0.16 mm from target–solder layer interface and at a distance of 0.78 mm from symmetry axis. The optimal design in target assembly has the combination of indium solder material, cobalt target at 12 mm thick, solder layer at 0.8 mm thick, copper backing plate at 15 mm thick. Moreover, solder material is the most important factor among control factors in the target assembly.

关键词： Co target assembly Solder Residual stress Simulation Taguchi method Optimal design

Superoscillation:from physics to optical applications

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Light(Science & Applications) 2019年第1期8卷 688-710页

作者： Gang Chen Zhong-quan Wen Cheng-Wei qiu College of Optoelectronic Engineering Chongqing University174 Shazheng StreetChongqing 400044China Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3Singapore 117583Singapore

The resolution of conventional optical elements and systems has long been perceived to satisfy the classic Rayleigh *** efforts have been made to develop different types of superresolution techniques to achieve optical resolution down to several nanometres,such as by using evanescent waves,fluorescence labelling,and *** imaging techniques,which are noncontact,far field and label free,are highly desirable but challenging to *** concept of superoscillation offers an alternative route to optical superresolution and enables the engineering of focal spots and point-spread functions of arbitrarily small size without theoretical *** paper reviews recent developments in optical superoscillation technologies,design approaches,methods of characterizing superoscillatory optical fields,and applications in noncontact,far-field and label-free superresolution *** work may promote the wider adoption and application of optical superresolution across different wave types and application domains.

关键词： optical oscillation resolution

Recent progress in studies of factors that elicil pancreatic β-cell expansion

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Protein & Cell 2015年第2期6卷 81-87页

作者： qiu Li zhi-Chun Lai Shandong Provincial Hospital Affiliated to Shandong University Jinan 250021 ChinaA Department of Biology The Pennsylvania State University University Park PA 16802 USA Department of Biochemistry and Molecular Biology The Pennsylvania State University University Park PA 16802 USA

The loss of or decreased functional pancreatic β-cell is a major cause of type 1 and type 2 diabetes. Previous studies have shown that adult β-cells can maintain their ability for a low level of turnover through replication and neogenesis. Thus, a strategy to prevent and treat dia- betes would be to enhance the ability of β-cells to increase the mass of functionalβ-cells. Consequently, much effort has been devoted to identify factors that can effectively induce β-cell expansion. This review focuses on recent reports on small molecules and protein fac- tors that have been shown to promote β-cell expansion.

关键词： pancreatic islet β-cell cell proliferation/replication/expansion cell signaling

Magnetic Field Effect on β^＋ Decay in the Crusts of Accreting Neutron Stars

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Communications in Theoretical Physics 2007年第4期47卷 765-768页

作者： ZHANG Jie LIU Men-quan LUO zhi-quan Institute of Physics and Electron Information China West Normal University Nanchong 637002 China

Based on shell model of nuclei, the influence of a high magnetic field on β^＋ decay in the crusts of accreting neutron stars is analyzed. The magnetic field effect on 54 Mn is discussed. The results show that a weak magnetic field makes little effect on β^＋ decay but a strong magnetic field （B 〉 10^11 G） improves β^＋ decay rates obviously. The conclusion derived will benefit to develop further research on nuclear astrophysics in the future.

关键词： β^+ decay strong magnetic field neutron star

Tunable Solid-State Dye Laser with Narrow Linewidth Operation

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Chinese Physics Letters 2001年第2期18卷 225-227页

作者： HONG zhi WANG zhi-Yu YANG Yu CHEN Jun WANG Min-quan BAO Cheng-Fang qiu Wen-Fa State Key Laboratory of Modern Optical Instrumentation Zhejiang UniversityHangzhou 310027 Department of Material Science Zhejiang UniversityHangzhou 310027

Tunable radiation with a linewidth of 0.014 nm was obtained in Rhodamine B,Rhodamine 6G,Perylene orange and Pyrromethene 567-doped GPTMS solid-state dye materials using intracavity grating dispersive *** solid dye samples were specially designed in the way in which they are gelling,drying and ageing between two anti-reflection coated disks,thus without any mechanical and optical *** conversion efficiency of 4.6%and the tunable range of 40 nm from 589-629 nm have been achieved in Rhodamine B-doped *** broadband lasing of 4.4 nm and 54%slope efficiency were also demonstrated in the experiment.

关键词： Tunable dye orange

On a Spanning K-tree Containing Specified Vertices in a Graph

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Acta Mathematicae Applicatae Sinica 2019年第4期35卷 919-923页

作者： Fei-fei SONG zhi-quan HU Department of Information & Computational Science He’nan Agricultural University Zhengzhou 450002 China Faculty ofMath & Statistics Central China Normal UniversityWuhan 430079 China

A k-tree is a tree with maximum degree at most k. In this paper, we give a sharp degree sum condition for a graph to have a spanning k-tree in which specified vertices have degree less than t, where 1≤t≤*** denote by σ_k(G) the minimum value of the degree sum of k independent vertices in a graph G. Let k≥2,s≥0 and 1≤t≤k be integers, and suppose G is an(s + 1)-connected graph with σ_k(G)≥|G|+(k-t)*** for any s specified vertices, G contains a spanning k-tree in which every specified vertex has degree at most t. This improves a result obtained by Matsuda and Matsumura.

关键词： spanning tree k-tree (s + 1)-connected graphs degree sum condition specified vertices