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Pion Cloud Effects on △-N Mass Splitting from Quark Models

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Communications in Theoretical Physics 2002年第8期38卷 189-194页

作者： dong Yu-Bing FENG qing-Guo Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918-4 Beijing 100039 China Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918-4 Beijing 100039 China

Pion cloud effects on △-N mass splitting are studied based on quark models. Pseudo-scalar pion-quarkcoupling is discussed in the relativistic and nonrelativistic frameworks. We separately calculate the pion cloud effects bythe one-pion exchange potential and by another method which is consistent with the baryon chiral perturbation *** able discrepancy in the mass splitting between the two methods is shown.

关键词： quark models, coupling constants, pion cloud, △-N mass splitting

Fatigue Life Evaluation Method for Foundry Crane Metal Structure Considering Load Dynamic Response and Crack Closure Effect

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Computer Modeling in Engineering & Sciences 2020年第2期122卷 525-553页

作者： qing dong Bin He Gening Xu School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuanChina.

To compensate for the shortcomings of quasi-static law in anti-fatigue analysis of foundry crane metal structures,the fatigue life evaluation method of foundry crane metal structure considering load dynamic response and crack closure effect is *** line with the theory of mechanical vibration,a dynamic model of crane structure during the working cycle is constructed,and dynamic coefficients under diverse actions are *** models of the internal force dynamic change process of dangerous cross-sections and a simulation model of first principal stress-time history are established by using the steel structure design criteria,which is utilised to extract the change of first principal stress of danger points over ***,the double-parameter stress spectrum is obtained by the rain flow counting *** fatigue life calculation formula is corrected by introducing a crack closure parameter that can be calculated by the stress ratio and the effective stress *** the finite element model imported into ***,crack propagation analysis is performed by the growth method in the fatigue integration module *** the metal structure of a 100/40t-28.5m foundry crane with track offset as an example,the accuracy of calculation results and the feasibility and applicability of the proposed method are verified by theoretical calculation and finite element simulation,which provide a theoretical basis for improvement of the fatigue resistance design of foundry cranes.

关键词： Metal structure of foundry crane load dynamic effect crack closure effect crack propagation fatigue life.

A point cloud segmentation method for power lines and towersbased on a combination of multiscale density features andpoint-based deep learning

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International Journal of Digital Earth 2023年第1期16卷 620-644页

作者： Wenbo Zhao qing dong Zhengli Zuo Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China International Research Center of Big Data for Sustainable Development Goals BeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China Laboratory of Target Microwave Properties Deqing Academy of Satellite ApplicationsZhejiangPeople’s Republic of China

The point segmentation of power lines and towers aims to use unmanned aerial vehicles(UAVs)for the inspection of power facilities,risk detection and *** of the unclear spatial relationship between the point clouds,the point segmentation of power lines and towers is *** this paper,the power line and tower point datasets are constructed using Light Detection and Ranging(LiDAR)and a point segmentation method is proposed based on multiscale density features and a point-based deep learning ***,the data are blocked and the neighbourhood is ***,the point clouds are downsampled to produce sparse point *** point clouds before and after sampling are rotated,and their density is ***,a direct mapping method is selected to fuse the density information;a lightweight network is built to learn the ***,the point clouds are segmented by concatenating the local features provided by *** algorithm performs effectively on different types of power lines and *** mean interaction over union is 82.73%,and the overall accuracy can reach 91.76%.This approach can achieve the end-to-end integration of segmentation and provide theoretical support for the segmentation of large scenic point clouds.

关键词： Power lines and power towers point cloud segmentation multiscale density features PointCNN

Uniform Homeomorphisms of Unit Spheres and Property H of Lebesgue–Bochner Function Spaces

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Acta Mathematica Sinica,English Series 2017年第5期33卷 681-690页

作者： qing Jin CHENG Yun Bai dong School of Mathematical Sciences Xiamen University School of Mathematics and Computer Wuhan Textile University

Assume that the unit spheres of Banach spaces X and Y are uniformly *** we prove that all unit spheres of the Lebesgue–Bochner function spaces Lp(μ, X) and Lq(μ, Y)are mutually uniformly homeomorphic where 1 ≤ p, q < ∞. As its application, we show that if a Banach space X has Property H introduced by Kasparov and Yu, then the space Lp(μ, X), 1 ≤ p < ∞,also has Property H.

关键词： Banach space uniform classification Property H Novikov conjecture

A New Generalization of Extended Tanh—Function Method for Solving Nonlinear Evolution Equations

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Communications in Theoretical Physics 2003年第6期39卷 647-652页

作者： ZHENGXue-dong CHENYong LIBiao ZHANGHong-qing DepartmentofAppliedMathematics DalianuniversityOfTechnologyDalian116024China

Making use of a new generalized ans?tze and a proper transformation, we generalized the extended tanh-function method. Applying the generalized method with the aid of Maple, we consider some nonlinear evolution equations. As a result, we can successfully recover the previously known solitary wave solutions that had been found by the extended tanh-function method and other more sophisticated methods. More importantly, for some equations, we also obtain other new and more general solutions at the same time. The results include kink-profile solitary-wave solutions, bell-profile solitary-wave solutions, periodic wave solutions, rational solutions, singular solutions and new formal solutions.

关键词： nonlinear evolution equations exact solutions symbolic computation Riccati equation

Marine spatio-temporal process semantics and its applications-taking the El Nio Southern Oscilation process and Chinese rainfall anomaly as an example

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Acta Oceanologica Sinica 2012年第2期31卷 16-24页

作者： XUE Cunjin dong qing XIE Jiong Key Laboratory of Digital Earth Science Center for Earth Observation and Digital EarthChinese Academy of SciencesBeijing 100094China State Key Laboratory of Resource and Environment Information System Institute of GeographicalScience and Natural ResourcesChinese Academy of SciencesBeijing 100101China

Spatio-temporal semantics based on ＂object views＂ or ＂event views＂ has few abilities to represent and model the continuity and gradual oceanic phenomena or objects, which seriously limits the specific marine applications and knowledge discovery and data mining, so this paper proposes a hierarchical abstraction semantics with ＂marine spatio-temporal process-life span phases-evolution sequences--state units＂ and process objects included by level with ＂marine process objects--phase objects--sequence object---state objects＂ with the oceanic process characteristics into the marine process semantics. In addition, this paper designs the storage and representation of marine process objects using the backus normal forms （BNF） and abstract data type （ADT）. Base on E1 Nifio Southern Oscilation （ENSO） index and Chinese rain gauging station data, this paper also gives a case of study. The spatio-temporal analysis between ENSO process and Chinese rainfall anomalies shows that the marine spatio-temporal semantics not only can illustrate the spatial distribution of Chinese rainfall anomalies in different time scales at ENSO process, life span phases and state units, but also analyze the dynamic changes of Chinese rainfall anomalies in different life span phases or state units within ENSO evolution.

关键词： marine process semantics hierarchical abstraction and inclusion by level ENSO proc ess rainfall anomalies

An Interpolation of Hardy Inequality and Moser–Trudinger Inequality on Riemannian Manifolds with Negative Curvature

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Acta Mathematica Sinica,English Series 2016年第7期32卷 856-866页

作者： Yan qing dong Qiao Hua YANG School of Mathematics and Statistics Wuhan University

Let M be a complete, simply connected Riemannian manifold with negative curvature. We obtain an interpolation of Hardy inequality and Moser-Trudinger inequality on M. Furthermore, the constant we obtain is sharp.

关键词： Moser-Trudinger inequality Hardy inequality Riemannian manifold negative curvature

DETACHED EDDY SIMULATION OF HYDRAULIC CHARACTERISTICS ALONG THE SIDE-WALL AFTER A NEW ARRANGEMENT-SCHEME OF THE SUDDEN LATERAL ENLARGEMENT AND THE VERTICAL DROP

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Journal of Hydrodynamics 2011年第5期23卷 669-675页

作者： LI Guo-jing DAI Guang-qing YANG qing MA Xu-dong State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

In order to study the cavitation damage in a side-wall when a sudden lateral enlargement and a vertical drop are imposed at the radial gate, a new arrangement-scheme is proposed, where the sudden lateral enlargement and the vertical drop can be imposed at the outlet of the gate chamber. The hydraulic characteristics along the side-wall are simulated by the detached eddy simulation and the Volume Of Fluid （VOF） method. The numerical results agree well with those of experiment. The experimental and numerical results show that the flow condition is smooth with only a weak water-wing appearing behind the lateral cavity, and the length of the lateral cavity becomes longer and is mainly affected by the size of the lateral enlargement and the zone of negative pressure after the water impacts the side-wall would disappear. The hydraulic characteristics of the new arrangement-scheme are beneficial to the prevention of the cavitation damage in the side-wall and the Detached Eddy Simulation （DES） with the VOF method can well predict the hydraulic characteristics after the new arrangement-scheme of the sudden lateral enlargement and the vertical drop.

关键词： model test aeration to prevent cavitation damage realizable k - ε turbulent model Detached Eddy Simulation (DES) Volume Of Fluid (VOF) method

Regioregular Asymmetric Diketopyrrolopyrrole Copolymers with Good Molecular Ordered Assembly Ability for High-performance Polymer Transistors

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Chinese Journal of Polymer Science 2023年第8期41卷 1215-1222,I0006页

作者： qing-qing Liu Jia-Xin Yang Man Zhao Can Gao Bo Guan Huan-Li dong Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

Introduction of asymmetric units into conjugated polymers is an important strategy to regulate the photophysical and electronic properties of polymers,as asymmetric units can not only regulate solubility and energy levels,but also molecular stacking and orientation,thus giving much higher optoelectronic ***,very few studies have been reported in this *** semiconducting properties of conjugated polymers could be regulated through regioregularity ***,we took the asymmetric thiophene/pyridine side group DPP as core and developed the regioregular monomer T-Py-DPP through three steps:alkyl chain introduction,tin monomer coupling and NBS double *** T-Py-DPP monomer was polymerized into reg-PPy TDPP-2FBT with a head-to-head *** regioregularity of T-Py-DPP unit endowed reg-PPy TDPP-2FBT with backbone planarity,self-assembly orientation,network-like morphology and high crystallinity in films,thus the superior bipolar transport *** highest hole and electron mobilities of reg-PPy TDPP-2FBT were 0.93 and 0.57 cm^(2)·V^(-1)·s^(-1),respectively,with 40%improvement relative to the regiorandom polymer.

关键词： Asymmetric copolymers Regioregularity Good orientation Organic field-effect transistor Enhanced performance