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On P≥3-factor Deleted Graphs

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Acta Mathematicae Applicatae sinica 2022年第1期38卷 178-186页

作者： si-zhong ZHOU zhi-ren SUN hong-xia liu School of Science Jiangsu University of Science and TechnologyZhenjiang 212100China School of Mathematical Sciences Nanjing Normal UniversityNanjing 210023China School of Mathematics and Information Sciences Yantai UniversityYantai 264005China

A spanning subgraph F of a graph G is called a path factor of G if each component of F is a path.A P≥k-factor means a path factor with each component having at least k vertices,where k≥2 is an ***,Benhamdine,Li and Wozniak[***,***,***,***,Partitioning vertices of 1-tough graph into paths,***.263(2001)255–261.]obtained a toughness condition for a graph to have a P≥*** introduce the concept of a P≥k-factor deleted graph,that is,if a graph G has a P≥k-factor excluding e for every e∈E(G),then we say that G is a P≥k-factor deleted *** this paper,we show four sufficient conditions for a graph to be a P≥3-factor deleted ***,it is shown that four results are best possible in some sense.

关键词： toughness isolated toughness connectivity P≥3-factor P≥3-factor deleted graph

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基于自研光谱仪的痕量气体光解速率测量研究

光谱学与光谱分析 2025年第1期45卷 15-23页

作者：李浩然曾议朱磊窦科刘志宏常振江宇司福祺中国科学院合肥物质科学研究院安徽光学精密机械研究所环境科学与技术重点实验室安徽合肥230031 中国科学技术大学科学岛分院安徽合肥230026 合肥大学生物食品与环境学院安徽合肥230601

光解速率及其测量技术最早由德国科学家提出,21世纪初Metcon公司开发了光解速率测量仪,该技术在国内得到关注,部分高校和公司对光解速率测量系统开展了研究和开发。国外产品一般体积较大,价格昂贵。国内产品中光谱仪、接收器等核心器件... 详细信息

光解速率及其测量技术最早由德国科学家提出,21世纪初Metcon公司开发了光解速率测量仪,该技术在国内得到关注,部分高校和公司对光解速率测量系统开展了研究和开发。国外产品一般体积较大,价格昂贵。国内产品中光谱仪、接收器等核心器件仍依赖于国外进口,易受国外技术封锁影响。在我国“十四五”国家重点研发计划中“大气与土壤、地下水污染综合治理”重点专项对化学气候综合站检测技术与装备需求引导下,研制了测量大气物质光解速率的光谱仪系统,并满足其核心部件国产化的要求。系统采用自主设计的小型光谱仪作为核心部件,配合各向均匀响应的光学接收器,经实验室光学定标后测得各种物质的光解速率。该系统工作波段为285~430 nm,时间分辨率可达0.1 s,可测物质包括NO_(2)、HONO、HCHO、H_(2)O_(2)等,与国外进口测量仪器对比,各气体物质光解速率的测量误差小于5%,相关性均超过0.93。采用该系统在合肥市董铺岛对大气中气体光解速率开展了长时间的连续监测。对NO_(2)光解速率变化趋势以及NO_(2)光解速率与浓度间的相关性进行分析,发现光解反应与驱动光化反应的能量密切相关,晴天的光解速率数值明显高于阴天与雨天。发现NO_(2)光解速率与浓度的积分曲线间存在一种经验公式,相关性大于0.9,可通过测量NO_(2)光解速率对NO_(2)浓度的累积量进行估计。该系统实现了核心部件的国产化,整体结构简单、便携,方便外场试验安装的同时,降低成本,提高经济性。研究为大气污染综合监测治理提供数据支撑,对各地区的环境监测及污染预防具有参考意义。

关键词：光解速率光谱仪辐亮度光学接收器

The isotropic energy function and formation rate of short gamma-ray bursts

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Research in Astronomy and Astrophysics 2021年第10期21卷 127-134页

作者： zhi-Ying liu fu-Wen Zhang si-Yuan Zhu College of Science Guilin University of TechnologyGuilin 541004China Key Laboratory of Dark Matter and Space Astronomy Chinese Academy of SciencesNanjing 210008China

Gamma-ray bursts(GRBs)are brief,intense,gamma-ray flashes in the universe,lasting from a few milliseconds to a few thousand *** short gamma-ray bursts(sGRBs)with duration less than 2 seconds,the isotropic energy(E_(iso))function may be more scientifically meaningful and accurately measured than the luminosity(Lp)*** this work we construct,for the first time,the isotropic energy function of s GRBs and estimate their formation ***,we derive the L_(p)-E_(p) correlation using 22 s GRBs with known redshifts and well-measured spectra and estimate the pseduo redshifts of 334 Fermi s ***,we adopt the Lynden-Bell c-method to study isotropic energy functions and formation rate of s GRBs without any assumption.A strong evolution of isotropic energy E_(iso)∝(1+z)^(5.79) is found,which is comparable to that between L_(p) and *** removing effect of the cosmic evolution,the isotropic energy function can be reasonably fitted by a broken power law,which is φ(E_(iso,0))∝E_(iso,0)^(-0.045) for dim sGRBs andφ(E_(iso,0))∝E_(iso,0)^(-1.11) for bright sGRBs,with the break energy 4.92×10^(49)*** obtain the local formation rate of s GRBs is about 17.43 events Gpc^(-3)yr^(-1).If assuming a beaming angle is 6° to 26°,the local formation rate including off-axis s GRBs is estimated as ρ_(0,all)=155.79-3202.35 events Gpc^(-3)yr^(-1).

关键词： gamma-ray bursts:general methods:data analysis

EntityManager： Managing Dirty Data Based on Entity Resolution

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Journal of Computer Science & Technology 2017年第3期32卷 644-662页

作者： Xue-Li liu hong-zhi Wang Jian-zhong Li hong Gao Massive Data Computing Laboratory Harbin Institute of Technology Harbin 150001 China

Data quality is important in many data-driven applications, such as decision making, data analysis, and data mining. Recent studies focus on data cleaning techniques by deleting or repairing the dirty data, which may cause information loss and bring new inconsistencies. To avoid these problems, we propose EntityManager, a general system to manage dirty data without data cleaning. This system takes real-world entity as the basic storage unit and retrieves query results according to the quality requirement of users. The system is able to handle all kinds of inconsistencies recognized by entity resolution. We elaborate the EntityManager system, covering its architecture, data model, and query processing techniques. To process queries efficiently, our system adopts novel indices, similarity operator and query optimization techniques. Finally, we verify the efficiency and effectiveness of this system and present future research challenges.

关键词： dirty data entity resolution uncertain attribute query processing query optimization

THE USE OF VISCO-ELASTOPLASTIC DAMAGE CONSTITUTIVE MODEL TO siMULATE NONLINEAR BEHAVIOR OF CONCRETE

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维普期刊数据库

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Acta Mechanica Solida sinica 2011年第5期24卷 411-428页

作者： Jun liu Gao Lin Bing fu hong zhong State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116023 China Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong China

A visco-elastoplastic damage constitutive model is proposed for simulating non-linear behavior of concrete. Based on traditional plastic theory, the irreversible deformation is simulated in effective stress space. In order to reflect different stiffness degradation mechanism of concrete under tensile and compressive loading conditions, both tensile and compressive damage variables are introduced, and then on the basis of energy release rate, the model is firmly derived within the concept of irreversible thermodynamics. The rate-dependent model is considered by introducing viscous regularization into the inelastic strain and damage variable, and combined with an additional elastic condition. fully implicit backward-Euler algorithm is used to perform constitutive integration. Results of numerical examples using the proposed model agree well with test results for specimens under uniaxial tension and compression, biaxial loading and triaxial loading. Failure processes of single-edge-notched （SEN） beam and double-edge-notched （DEN） specimen are also simulated to further validate the proposed model.

关键词： damage rate-dependent plasticity thermodynamics energy release rate nonlinear behavior concrete

A protein-enabled protective film with functions of self-adapting and anion-anchoring for stabilizing lithium-metal batteries

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Journal of Energy Chemistry 2022年第1期31卷 485-495,I0013页

作者： Chenxu Wang Xuewei fu Shengnan Lin Jin liu Wei-hong zhong School of Mechanical and Materials Engineering Washington State UniversityPullmanWA 99164USA

Practical implementations of rechargeable lithium(Li)metal batteries have long been plagued by multiple problems of Li anode,such as Li dendrite growth,large volume change,low Coulombic ***,we report a protein-enabled film that can provide effective protection for Li *** protective film with an integrated design of high flexibility,strong adhesion and high Li-ion transference number(0.80)is fabricated by incorporating denatured zein(corn protein)with polyethylene oxide(PEO)acting as an age nt for sustaining the denatured protein chains against refolding via the intermolecular interactions between ***,a conformable zein-enabled protective film(zein@PEO)with simultaneous en hancement in flexibility,modulus and adhesion strength is gen erated to offer both functi ons of self-adapting and anion-anchoring *** results show that the zein@PEO film is able to accommodate the volume change,reduce the side reactions,and homogenize the ion *** from these significant properties/fu nctions,the Li/Cu cell with the zein@PEO film delivers prolonged cycle life for over 500 hours with stable *** with LiMn_(2)O_(4) cathode,the capacity,cycle stability and rate performance of the cell are remarkably improved as well,demonstrati ng the effectiveness in stabilizing Li metal batteries.

关键词： Zein Self-adapting Flexibility Lithium metal Lithium dendrite

Field investigation and numerical simulation on rockfalls in Zhangmu Town, Tibet, China

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Journal of Mountain Science 2022年第3期19卷 740-755页

作者： WANG zhong-fu liu Han-dong HE si-ming BI Dan North China University of Water Resources and Electric Power Zhengzhou 450046China Henan Key Laboratory of Geotechnical and Structure Engineering Zhengzhou 450046China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China China Liaohe Petroleum Engineering co. LTDPanjin124010China

Zhangmu Town in Tibet of China,which lies in the southern piedmont of the median Himalayas,is a small but strategically important port of trade exchange between China and *** rockfall events have occurred in Zhangmu since 1970,resulting in huge economic losses and serious influence on the bilateral *** conducted a detailed field investigation on the high and steep slope in Zhangmu Town,and analyzed the distribution features,stability,failure modes and evolution of dangerous rocks of potential *** we numerically simulated the movement path,velocity and accumulation forms of the rockfall with PFC^(3D) *** results indicated that the dangerous rock belt could be divided into three sections,namely,unstable section,slightly stable section and basically stable *** was estimated that the rock debris and single dangerous rock would be unstable in the case of earthquakes or *** to the terrain constraints,the fallen rocks would scatter near the mouth of the Zhangmu ditch and in the Buqu River through multiple times of rolling,collision-induced diversion and *** reinforcement,the rockfall could cause serious damage to the car parks,gas stations and National Highway 318 along the line from Zhangmu Town to Zhangmu *** on the field survey and numerical simulation,we recommended rockfall removal and interception as the major prevention measures,and protective sheds as auxiliary measure.

关键词： Rockfalls Failure mode Stability analysis Numerical simulation Micro parameters Prevention measures

Variational Principle for Topological Pressure on Subsets of Free Semigroup Actions

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Acta Mathematica sinica,English Series 2021年第9期37卷 1401-1414页

作者： Xing fu zhong zhi Jing CHEN School of Mathematics and Statistics Guangdong University of Foreign StudiesGuangzhou 510006P.R.China School of Mathematics and Systems Science Guangdong Polytechnic Normal UniversityGuangzhou 510665P.R.China

We investigate the relations between Pesin–Pitskel topological pressure on an arbitrary subset and measure-theoretic pressure of Borel probability measures for finitely generated semigroup ***(X,G)be a system,where X is a compact metric space and G is a finite family of continuous maps on *** a continuous function f on X,we define Pesin–Pitskel topological pressure PG(Z,f)for any subset Z■X and measure-theoretical pressure Pμ,G(X,f)for anyμ∈M(X),where M(X)denotes the set of all Borel probability measures on *** any non-empty compact subset Z of X,we show that PG(Z,f)=sup{Pμ,G(X,f):μ∈M(X),μ(Z)=1}.

关键词： Topological pressure measure-theoretic pressure semigroup of continuous maps variational principle

Crystallography of precipitates in Mg alloys

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Journal of Magnesium and Alloys 2021年第2期9卷 416-431页

作者： Zhang-zhi Shi hong-Ting Chen Ke Zhang fu-zhi Dai Xue-Feng liu Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Key Laboratory for Advanced Materials Processing of Ministry of EducationSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China Science and Technology on Advanced functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China

Crystallography of precipitates in Mg alloys is indispensable to explain and predict alloy microstructures and *** order to obtain a global understanding of diversified experimental results,a general theory of singular interface is introduced,which provides the physical base and calculation methodology for interpreting precipitate morphology and orientation relationship(OR),especially useful for understanding irrational facets and *** by the theory,recent experimental findings are systematically summarized,including thermally stable and metastable precipitates with various crystal ***,theoretical advances inspired by the findings are introduced,which deepens our understanding on OR selection and preference of irrational *** last,future research directions in this field are proposed.

关键词： Mg alloys Precipitation Facet Orientation relationship