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Fredholm Composition Operators on Riemann Surfaces

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Acta Mathematica Sinica,English Series 2005年第4期21卷 869-872页

作者： guang Fu cao Department of Mathematics Guangzhou University Guangzhou 510405 P. R. China

It is proved that the invertibility of a composition operator on the differential form space for a Riemann surface is equivalent to its Fredholmness. In addition, the Fredholmness of weighted composition operators is ... 详细信息

关键词： Riemann surface Composition operator Fredholm operator

Trace Class Toeplitz Operators with Unbounded Symbols on Weighted Bergman Spaces

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Acta Mathematica Sinica,English Series 2010年第8期26卷 1567-1574页

作者： Sui HUANG guang Fu cao Departement of Mathematics Guangzhou University Guangzhou 510006 P. R. China

In this note we construct a function φ in L2（Bn,dμ） which is unbounded on any neighborhood of each boundary point of Bn such that Tφ is a trace class operator on weighted Bergman space Lα2（Bn,dμ） for several ... 详细信息

关键词： Toeplitz operator unbounded function compact operator

The Role of BMOA in the Boundedness of Weighted Composition Operators on the Unit Ball

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Acta Mathematica Sinica,English Series 2014年第2期30卷 323-330页

作者： Chao ZHANG guang Fu cao College of Mathematics and Information Sciences Guangzhou University

We study the weighted composition operators Wh,on Hardy space H2（B） whenever h ∈ BMOA（resp.h ∈ VMOA）.Analogous results are given for Hp（B） spaces and the scale of weighted Bergman *** the latter case,BMOA is... 详细信息

关键词： Weighted composition operator boundedness compactness BMOA VMOA

New high-T_c iron-selenide superconductor with hydroxide spacer layers

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Science China Materials 2015年第1期58卷 1-2页

作者： guang-Han cao Department of Physics Zhejiang University

Iron-based superconductors include pnictides and *** far,the chalcogenides are much fewer in number[1],thus it is particularly valuable to find new superconductors in iron chalcogenides,for the'ultimate'understanding of iron-based *** tetragonal binary iron selenide(β-Fe1+δSe)is the structurally simplest iron-based superconductor with a superconducting critical temperature(Tc)of 8.5 K at ambient pressure[2].By intercalation of alkali metal ions into

关键词： high New high-T_c iron-selenide superconductor with hydroxide spacer layers Chen

Prediction of the Charpy V-notch impact energy of low carbon steel using a shallow neural network and deep learning

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International Journal of Minerals,Metallurgy and Materials 2021年第8期28卷 1309-1320页

作者： Si-wei Wu Jian Yang guang-ming cao State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

The impact energy prediction model of low carbon steel was investigated based on industrial data. A three-layer neural network, extreme learning machine, and deep neural network were compared with different activation functions, structure parameters, and training functions. Bayesian optimization was used to determine the optimal hyper-parameters of the deep neural network. The model with the best performance was applied to investigate the importance of process parameter variables on the impact energy of low carbon steel. The results show that the deep neural network obtains better prediction results than those of a shallow neural network because of the multiple hidden layers improving the learning ability of the model. Among the models, the Bayesian optimization deep neural network achieves the highest correlation coefficient of 0.9536, the lowest mean absolute relative error of 0.0843, and the lowest root mean square error of 17.34 J for predicting the impact energy of low carbon steel. Among the variables, the main factors affecting the impact energy of low carbon steel with a final thickness of7.5 mm are the thickness of the original slab, the thickness of intermediate slab, and the rough rolling exit temperature from the specific hot rolling production line.

关键词： prediction shallow neural network deep neural network impact energy low carbon steel

Tebufenozide resistance is associated with sex-linked inheritance in Plutella xylostella

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Insect Science 2015年第2期22卷 235-242页

作者： guang-Chun cao Zhao-Jun Han Entomology Department/Key Laboratory of Monitoring and Management of Plant Diseases and Insects Ministry of Agriculture NanjingAgricultural University Nanjing State Key Laboratory for Biology of Plant Disease and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural Sciences Beijing China

The diamondback moth （DBM）, Plutella xylostella （L.）, is a major pest of cruciferous crops. Tebufenozide, a novel nonsteroidal ecdysone agonist, exhibits good efficacy and has played an increasingly important role in the control of Lepidopteran pests in China. For its resistance management, the genetic basis of tebufenozide resistance was studied using a laboratory selected resistant strain of DBM （resistant ratio, RR = 268）. A series of crosses with laboratory susceptible and resistant strains revealed that tebufenozide resistance in this pest was partially biased toward female heredity, with a large difference in RR for F1 （RR = 29） and rF1 progeny （RR = 147）. The dominance calculated for these 2 cross progeny was -0.788 and 0.09, respectively. Further analysis showed that the susceptible male and female larvae were similar in theft sensitivity to tebufenozide, but the resistant female larvae showed significantly higher resistance than the resistant male larvae. The heredity of tebufenozide resistance in DBM might be linked with the W sex chromosome, which suggested that DBM has the ability to develop high levels of resistance to tebufenozide. This is the first report of sex-linked inheritance oftebufenozide resistance in P xylostella （L.）.

关键词： insecticide resistance Plutella xylostella sex linkage tebufenozide

Wandering Subspaces and Quasi-wandering Subspaces in the Hardy-Sobolev Spaces

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Acta Mathematica Sinica,English Series 2017年第12期33卷 1684-1692页

作者： Jie Sheng XIAO guang Fu cao Nanhu College Jiaxing University Department of Mathematics South China Apicultural University

In this paper, we prove that for -1/2≤β≤0, suppose M is an invariant subspaces of the Hardy Sobolev spaces Hβ^2（D） for Tz^β, then M zM is a generating wandering subspace of M, that is, M = [M zM]Tz^β. Moreover, any non-trivial invariant subspace M of Hβ^2（D） is also generated by the quasi-wandering subspace PMTz^βM^⊥, that is, M = [PMTz^βM^⊥]Tz^β.

关键词： Hardy-Sobolev space invariant subspace wandering subspace quasi-wandering sub- space Beurling type theorem

Toeplitz Operators with BMO Symbols of Several Complex Variables

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Acta Mathematica Sinica,English Series 2012年第3期28卷 599-608页

作者： Zhong Hua HE guang Fu cao School of Mathematics and Information Sciences Guangzhou University

In this note we prove that the boundedness and compactness of the Toeplitz operator on the Bergman space L2a （Bn） for several complex variables with a BMO1 symbol is completely determined by the boundary behavior of... 详细信息

关键词： Toeplitz operator Bergman space Berezin transform

Operators on Differential Form Spaces for Riemann Surfaces

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Acta Mathematica Sinica,English Series 2007年第5期23卷 925-934页

作者： guang Fu cao Xiao Feng WANG Department of Mathematics Guangzhou University Guangzhou 510405 P. R. China

In the present paper, a problem of Ioana Mihaila is negatively answered on the invertibility of composition operators on Riemann surfaces, and it is proved that the composition operator Cp is Predholm if and only if it is invertible if and only if p is invertible for some special cases. In addition, the Toeplitz operators on ∧1 2, a（M） for Riemann surface M are defined and some properties of these operators are discussed.

关键词： Riemann surface Composition operator Toeplitz operator