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The closed finite-to-one mappings and their applications

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Applied Mathematics(A Journal of Chinese Universities) 2019年第2期34卷 149-161页

作者： YANG Jie lin shou School of Mathematics and Statistics Minnan Normal UniversityZhangzhouFujian 363000China Department of Mathematics Ningde Normal UniversityNingdeFujian 352100China

In this paper,we discuss the closed finite-to-one mapping theorems on generalized metric spaces and their *** is proved that point-G_δ properties,■-snf-countability and csf-countability are invariants and inverse invariants under closed finite-to-one *** the relationships between the weak first-countabilities,we obtain the closed finite-to-one mapping theorems of weak quasi-first-countability,quasi-first-countability,snf-countability,gfcountability and ***,these results are applied to the study of symmetric products of topological spaces.

关键词： nite-to-one mappings closed mappings weak first-countability sn-networks cs-networks symmetric products

On the Countable Tightness of Product Spaces

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Acta Mathematica Sinica,English Series 2005年第4期21卷 929-936页

作者： Chuan LIU shou lin Department of Mathematics Ohio University Zanesville Campus Zanesville OH43701 USA Department of Mathematics Ningde Teachers' College Ningde 352100 P. R. China

In this paper, we discuss the countable tightness of products of spaces which are quotient simages of locally separable metric spaces, or k-spaces with a star-countable k-network. The main result is that the following conditions are equivalent：（1） b = ω1; （2） t（Sω×Sω1）〉 ω; （3） For any pair （X, Y）, which are k-spaces with a point-countable k-network consisting of cosmic subspaces, t（X×Y）≤ω if and only if one of X, Y is first countable or both X, Y are locally cosmic spaces. Many results on the k-space property of products of spaces with certain k-networks could be deduced from the above theorem.

关键词： Countable tightness k-spaces Cosmic spaces Product spaces k-networks Point-countablecollections Star-countable collections

Spaces with σ-point-discrete N_0-weak bases

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Applied Mathematics(A Journal of Chinese Universities) 2013年第1期28卷 116-126页

作者： SHEN Rong-xin lin shou Department of Mathematics Taizhou Teachers' College Department of Mathematics Nanjing University Department of Mathematics Ningde Normal University

It is discussed in this paper the spaces with σ-point-discrete N_0-weak bases. The main results are：（1） A space X has a σ-compact-finite N_0-weak base if and only if X is a k-space with a σ-point-discrete N_0-weak base; （2） Under （CH）, every separable space with a σ-point-discrete N_0-weak base has a countable N_0-weak base.

关键词： N_0-weak base σ-point-discrete network σ-compact-finite network separable space.

Simple zero property of some holomorphic functions on the moduli space of tori

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Science China Mathematics 2019年第11期62卷 2089-2102页

作者： Zhijie Chen Ting-Jung Kuo Chang-shou lin Department of Mathematical Sciences and Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China Department of Mathematics Taiwan Normal UniversityTaipei 11677China Taida Institute for Mathematical Sciences(TIMS) Center for Advanced Study in Theoretical Sciences(CASTS)Taiwan UniversityTaipei 10617China

We prove that some holomorphic functions on the moduli space of tori have only simple *** of computing the derivative with respect to the moduli parameter τ, we introduce a conceptual proof by applying Painlevé Ⅵ equation. As an application of this simple zero property, we obtain the smoothness of the degeneracy curves of trivial critical points for some multiple Green function.

关键词： simple zero property Painlevé Ⅵ equation Green function

MOTION OF TRACER PARTICLES IN A CENTRIFUGAL PUMP AND ITS TRACKING CHARACTERISTICS

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Journal of Hydrodynamics 2012年第5期24卷 785-793页

作者： LI Ya-lin YUAN shou-qi TANG Yue YUAN Jian-ping Research Center of Fluid Machinery Engineering and Technology Jiangsu University Zhenjiang 212013 China

The Basset-Boussinesq-Oseen （BBO） equation can be used for most flows to trace the motion of a particle, but in a centrifugal pump, among the forces that act on the particles, one should also include those due to the impeller rotation, as additional effects. This paper firstly reviews various approximations of the BBO equation for the motion of dispersion particles in a viscous fluid. Then based on the motion equation for particles in low Reynolds number centrifugal pumps, a formula for calculating the tracking characteristics of tracer particles is deduced through the Fourier integral transformation. After that the deviations of the particle motion from the fluid motion, as predicted by the various approximations, are discussed and compared. At last, with an emphasis on the Particle Image Velocimetry （PIV） results, the tracking characteristics of particles are estimated. Also, advantages and disadvantages of different tracer particles are discussed and suitable tracer particles for application in PIV studies for flow fields in centrifugal pumps are suggested.

关键词： tracer particles equations of motion tracking characteristics centrifugal pump Particle Image Velocimetry (PIV)

Some Notes on Closed Sequence-Covering Maps

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Journal of Mathematical Research with Applications 2014年第1期34卷 97-104页

作者： Fucai lin shou lin School of Mathematics and Statistics Minnan Normal University Institute of Mathematics Ningde Teachers' College

In this paper,we mainly discuss the images of certain spaces under closed sequencecovering *** is showed that the property with a locally countable weak base is preserved by closed sequence-covering *** the following question is discussed:Are the closed sequence-covering images of spaces with a point-countable sn-network sn-first countable?

关键词： closed maps sequence-covering maps weak bases sn-networks cs-networks k-semistratifiable spaces.

Researches on point-discrete families

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Frontiers of Mathematics in China 2023年第6期18卷 415-430页

作者： shou lin Rongxin SHEN School of Mathematics and Statistics Minnan Normal UniversityZhangzhou 363000China Institute of Mathematics Ningde Normal UniversityNingde 352100China Department of Mathematics and Physics Taizhou UniversityTaizhou 225300China

Based on the modern development of Metrization theorem for context,the main results obtained in recent ten years on point-discrete families are *** paper mainly introduces the theory of the spaces with opoint-discrete bases,the spaces with certain o-point-discrete networks,and the relationship between the above spaces and the spaces with certain o-compactfinite networks.

关键词： Point-discrete families compact-finite families generalized metrizable spaces k-net weak bases

On Some Aspects of Perturbation Analysis for Matrix Cone Optimization Induced by Spectral Norm

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Journal of the Operations Research Society of China 2015年第3期3卷 275-296页

作者： Shao-Yan Guo Li-Wei Zhang shou-lin Hao School of Mathematical Sciences Institute of Operations Research and Control TheoryDalian University of TechnologyDalian 116024China School of Control Science and Engineering Institute of Advanced Control TechnologyDalian University of TechnologyDalian 116024China

In this paper,we consider a cone problem of matrix optimization induced by spectral norm(MOSN).By Schur complement,MOSN can be reformulated as a nonlinear semidefinite programming(NLSDP)*** we discuss the constraint nondegeneracy conditions and strong second-order sufficient conditions of MOSN and its SDP reformulation,and obtain that the constraint nondegeneracy condition of MOSN is not always equivalent to that of ***,the strong second-order sufficient conditions of these two problems are equivalent without any ***,a sufficient condition is given to ensure the nonsingularity of the Clarke’s generalized Jacobian of the KKT system for MOSN.

关键词： Spectral norm Negative semidefinite cone Strong second-order sufficient condition Constraint nondegeneracy condition

Fine-grained distributed averaging for large-scale radio interferometric measurement sets

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Research in Astronomy and Astrophysics 2021年第4期21卷 93-100页

作者： shou-lin Wei Kai-Da Luo Feng Wang Hui Deng Ying Mei Faculty of Information Engineering and Automation Computer Technology Application Key Lab of Yunnan ProvinceKunming University of Science and TechnologyKunming 650500China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China

The Square Kilometre Array(SKA)would be the world’s largest radio telescope with eventually over a square kilometre of collecting ***,there are enormous challenges in its data *** use of modern distributed computing techniques to solve the problem of massive data processing in the SKA is one of the most important *** this study,basing on the Dask distribution computational framework,and taking the visibility function integral processing as an example,we adopt a multi-level parallelism method to implement distributed averaging over time and *** Array was used to implement super large matrix or arrays with supported *** maximize the usage of memory,we further exploit the data parallelism provided by Dask that intelligently distributes the computational load across a network of computer agents and has a built-in fault tolerance *** validity of the proposed pattern was also verified by using the Common Astronomy Software Application(CASA),wherein we analyze the smearing effects on images reconstructed from different resolution visibilities.

关键词： techniques:interferometric methods:data analysis methods:numerical instrumentation:interferometers