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line-primitive linear Spaces with fang-li Parameter gcd（k,r） at Most 12

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Acta Mathematica Sinica,English Series 2011年第4期27卷 657-670页

作者： Sheng lin ZHOU Yan Bo MA Wei Dong fang Department of Mathematics South China University of Technology Guangzhou 510641 P. R. China Department of Mathematics and Information Technology Hanshan Normal University Chaozhou 521041 P. R. China

Let G be a subgroup of the automorphism group of a non-trivial finite linear space $. In this paper we prove that if G is line-primitive with fang-li parameter gcd（k, r） = 11 and 12, then G is also point-primitive. This extends the results of fang and li （1993） and li and liu （2001） which combined gives the result for gcd（k,r） ≤ 10.

关键词： Finite linear spaces line-primitive point-imprimitive

Generalized bounds on the partial periodic correlation of complex roots of unity sequence set

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 207-210页

作者： li-fang FENG Institute of Mobile Communication Southwest Jiaotong University Chengdu 610031 China

In this paper,the generalized bounds are derived on the partial periodic correlation of complex roots of unity sequence set with zero or low correlation zone(ZCZ/LCZ)as the important criteria of the sequence design and *** derived bounds are with respect to family size,subsequence length,maximum partial autocorrelation sidelobe,maximum partial cross-correlation value and the ZCZ/*** results show that the derived bounds include the previous periodic bounds,such as Sarwate bound,Welch bound,Peng-Fan bound and Paterson-Lothian bound,as special cases.

关键词： Partial correlation Zero correlation zone (ZCZ) Low correlation zone (LCZ) CDMA

On the structure and representations of non-balanced quantum doubles

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Applied Mathematics(A Journal of Chinese Universities) 2012年第4期27卷 475-488页

作者： CHEN li-li li fang College of Mathematics and Physics Qingdao University of Science and TechnologyQingdao 266061China Department of Mathematics Zhejiang UniversityHangzhou 310027China

For a field k and two finite groups G and X, when G acts on X from the right by group automorphisms, there is a Hopf algebra structure on k-space （kX°P）＊ kG （see Theorem 2.1）, called a non-balanced quantum double and denoted by Dx（G）. In this paper, some Hopf algebra properties of Dx （G） are given, the representation types of Dx （G） viewed as a k-algebra are discussed, the algebra structure and module category over Dx（G） are studied. Since the Hopf algebra structure of non-balanced quantum double DX （G） generMizes the usual quantum double D（G） for a finite group G, all results about Dx（G） in this paper can also be used to describe D（G） as a special case and the universal R-matrix of Dx （G） provides more solutions of Yang-Baxter equation.

关键词： non-balanced quantum double Hopf Mgebra representation type quasi-triangularity quiver.

A Remark on З-Permutability of Finite Groups

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Acta Mathematica Sinica,English Series 2007年第11期23卷 1985-1990页

作者： li fang WANG School of Mathematics Zhongshan University Guangzhou 510275 P. R. China Department of Mathematics Shanxi Teachers University Linfen 041004 P. R. China lingnan College and School of Mathematics Zhongshan University Guangzhou 510275 P. R. China Department of Mathematics Nanchang University Nanchang 330047 P. R. China

Let З be a complete set of Sylow subgroups of a finite group G, that is, З contains exactly one and only one Sylow p-subgroup of G for each prime p. A subgroup of a finite group G is said to be З-permutable if it permutes with every member of З. Recently, using the Classification of Finite Simple Groups, Heliel, li and li proved tile following result： If the cyclic subgroups of prime order or order 4 iif p = 2） of every member of З are З-permutable subgroups in G, then G is supersolvable.In this paper, we give an elementary proof of this theorem and generalize it in terms of formation.

关键词： З-permutable subgroups supersolvable groups saturated formations

Periodicities in Cluster Algebras and Cluster Automorphism Groups

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Algebra Colloquium 2021年第4期28卷 601-624页

作者： Siyang liu fang li Department of Mathematics Zhejiang University(Yuquan Campus)Hangzhou 310027China Zhejiang Institute of Modern Physics Zhejiang University(Yuquan Campus)Hangzhou 310027China

We study the relations between two groups related to cluster automorphism groups which are defined by Assem,Schiffler and *** establish the relation-ships among(strict)direct cluster automorphism groups and those groups consisting of periodicities of labeled seeds and exchange matrices,respectively,in the language of short exact *** an application,we characterize automorphism-finite cluster algebras in the cases of bipartite seeds or finite mutation ***,we study the relation between the group Aut(A)for a cluster algebra A and the group AutMn(S)for a mutation group Mn and a labeled mutation class S,and we give a negative answer via counter-examples to King and Pressland's problem.

关键词： cluster algebra mutation cluster automorphism group periodicity

Theoretical Study on Dihydrogen Bonds of NH3BH3 with Several Small Molecules

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Chinese Journal of Chemical Physics 2009年第1期22卷 57-62页

作者： An-yong li li-fang Xu Zhou ling School of Chemistry and Chemical Engineering Southwest University Chongqing 400715 China

The dihydrogen bonds B-H...H-X （X= the complexes of NH3BH3 with HF, HCl, F, Cl, Br, C, O, N） in the dimer （NH3BH3）2 and HBr, H2CO, H20, and CH3OH were theoretically studied. The results show that formation of the dihydrogen bond leads to elongation and stretch frequency red shift of the BH and XH bonds, except that in the H2CO system, the CH bond blue shifts. For （NH3BH3）2 and the complexes of the halogenides, red shifts of the XH bonds are caused by the intermolecular hyperconjugation σ（BH）→σ^＊（XH）. For the system of H2CO, a blue shift of the CH bond is caused by a decrease of the intramolecular hyperconjugation n（O→σ^＊（CH）. In the other two systems, the red shift of OH bond is a secondary effect of the stronger traditional red-shifted H-bonds N-H... O. In all these systems, red shifts of the BH bonds are caused by two factors： negative repolarization and negative rehybridization of the BH bond, and decrease of occupancy on σ（BH） caused by the intermolecular hyperconjugation σ（BH）→σ^＊（XH）.

关键词： B-H...H-X dihydrogen bond Red and blue shift Negative repolarization and negative rehybridization

地应力影响下的五孔掏槽爆破岩石损伤效应研究

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火工品 2025年第1期 89-96页

作者：杨赛群葛立芳李洪伟夏治园安徽江南爆破工程有限公司安徽宣城242000 安徽江南化工股份有限公司安徽合肥230088 安徽理工大学化工与爆破学院安徽淮南232001

在地下矿山开采过程中,地应力对巷道掘进效率的影响日益显著。本研究以某地下铁矿为研究对象,采用有限元软件LS-DYNA模拟不同地应力条件下五孔掏槽爆破掏槽孔孔间延期时间对岩石损伤程度的影响。通过现场爆破实验和块度识别软件验证模... 详细信息

在地下矿山开采过程中,地应力对巷道掘进效率的影响日益显著。本研究以某地下铁矿为研究对象,采用有限元软件LS-DYNA模拟不同地应力条件下五孔掏槽爆破掏槽孔孔间延期时间对岩石损伤程度的影响。通过现场爆破实验和块度识别软件验证模拟结果,探究了地应力、孔间延期时间与岩石损伤程度之间的关系。研究结果表明,地应力由0 MPa增加到10 MPa,五孔掏槽爆破掏槽孔最佳延期时间由60 ms减少为10 ms,相应的岩石损伤程度降低79%。地应力对爆破远区岩石裂纹的发育影响较大,而对近区影响较小。现场实验进一步证实了数值模拟的结论,表明可以根据实际地应力大小合理设置延期时间,有效降低大块率,提高爆破效率。

关键词：五孔掏槽爆破地应力延期时间 LS-DYNA 损伤程度

Enhanced visible light photoactivity of TiO_(2)/SnO_(2) films by tridoping with Y/F/Ag ions

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Journal of Rare Earths 2022年第4期40卷 616-625,I0004页

作者： lizhu Zhao Guobao li fang li Mingming Yao School of Chemistry and Chemical Engineering University of JinanJinan 250022China

The Y,F,and Ag tridoped TiO_(2)/SnO_(2) composite nanocrystalline film(YFAg–TS)with prominent photocatalytic performance was prepared by the modified sol–gel method and was characterized by utilizing X-ray diffraction(XRD),differential thermal and thermogravimetric(DTA–TG)analysis,scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),Brunauer–Emmett–Teller(BET)method,ultraviolet–visible diffuse reflectance spectroscopy(UV–vis DRS),and photoluminescence(PL).The XRD and DTA–TG results expose that the YFAg–TS catalyst is a mixed phase consisting of anatase,rutile,and chlorargyrite,which is beneficial to improving the photocatalytic performance of TiO_(2).The SEM,TEM,and BET results disclose that the YFAg–TS film has smaller nanoparticles,higher specific surface area,and narrower pore size compared with pure TiO_(2) *** XRD and TEM results exhibit that a part of yttrium can enter the TiO_(2) lattice to induce lattice *** XPS results confirm the presence of Y^(3+)state in the YFAg–TS sample,and Y^(3+)ions can act as the trapping site of electrons to expedite the separation of electrons and *** UV–vis DRS results reveal that the YFAg–TS film has an obvious absorption edge shift and a narrower bandgap(2.70 eV)compared with pure TiO_(2) *** PL results show that the YFAg–TS film has the highest photogenerated electrons and holes separation efficiency and charges transfer efficiency among all *** photocatalytic activity of the YFAg–TS was assessed by monitoring the degradation of methyl green and formaldehyde *** results manifest that the YFAg–TS film has high stability and excellent photocatalytic *** possible synergistic photocatalytic mechanism of YFAg–TS films has been discussed in this paper.

关键词： TiO_(2)film Y/F/Ag tridoping SnO_(2)coupling Photoactivity Rare earths

VARIATIONAL IMAGE FUSION WITH FIRST AND SECOND-ORDER GRADIENT INFORMATION

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Journal of Computational Mathematics 2016年第2期34卷 200-222页

作者： fang li Tieyong Zeng Department of Mathematics East China Normal University and Shanghai Key Laboratory of Pure Mathematics and Mathematical Practice Shanghai China Department of Mathematics Hong Kong Baptist University Kowloon Tong Hong Kong

Image fusion is important in computer vision where the main goal is to integrate several sources images of the same scene into a more informative image. In this paper, we propose a variational image fusion method based on the first and second-order gradient information. Firstly, we select the target first-order and second-order gradient information from the source images by a new and simple salience criterion. Then we build our model by requiring that the first-order and second-order gradient information of the fused image match with the target gradient information, and meanwhile the fused image is close to the source images. Theoretically, we can prove that our variational model has a unique minimizer. In the numerical implementation, we take use of the split Bregman method to get an efficient algorithm. Moreover, four-direction difference scheme is proposed to discrete gradient operator, which can dramatically enhance the fusion quality. A number of experiments and comparisons with some popular existing methods demonstrate that the proposed model is promising in various image fusion applications.

关键词： Image fusion Feature selection Bounded variation Second bounded variation,Split Bregman