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Defect Mode Computation in Two-Dimensional Photonic Crystals Consisting of Nearly-Free-Electron Metals

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Chinese Physics Letters 2001年第9期18卷 1218-1221页

作者： xiao san-shui HE Sai-Ling LIN Qing-Chun SHEN Lin-Fang Centre for Optical and Electromagnetic Research State Key Laboratory for Modern Optical InstrumentationZhejiang UniversityHangzhou 310027 Department of Electromagnetic Theory Royal Institute of TechnologyS-10044 StockholmSweden Department of Physics Zhejiang UniversityHangzhou 310027

Defect modes in two-dimensional photonic crystals consisting of nearly-free-electron metals are considered. To avoid any time-consuming time convolution, modified time stepping formulae are used in a finite-difference time-domain (FDTD) method. Compared to the FDTD transmission spectra method, the present method significantly reduces the computation domain. With the present method one can also find defect modes that are not excited by the incident plane wave in the FDTD transmission spectra method.

关键词： method. Crystal Electron

Theoretical Analysis of a Vertical Channel Dropping Tunnelling Process in a Photonic Crystal for Wavelength Division Demultiplexing

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Chinese Physics Letters 2001年第12期18卷 1613-1616页

作者： FU Jian HE Sai-Ling xiao san-shui QIU Min HE Jian-Jun Centre for Optical and Electromagnetic Research State Key Laboratory for Modern Optical InstrumentationZhejiang UniversityHangzhou 310027 Department of Electromagnetic Theory Royal Institute of TechnologyS-10044 StockholmSweden

A theoretical analysis is presented for a channel drop tunnelling structure composed of a horizontal input channel, a vertical output channel and a multi-mode cavity in a photonic crystal. Criteria for a complete transfer are derived for applications of wavelength division demultiplexing. The analytical results are verified with a numerical simulation using a finite difference time domain method. The vertical channel dropping tunnelling system makes the demultiplexing device much more compact, as compared to the conventional parallel channel dropping system.

关键词： channel multiplexing Crystal

低频和高频区域内大禁带的二维各向异性光子晶体

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物理学报 2002年第12期51卷 2858-2864页

作者：肖三水沈林放何赛灵浙江大学现代光学仪器国家重点实验室光及电磁波研究中心杭州310027

采用一种改进的平面波展开法 ,运用一种有效的设计二维各向异性光子晶体的方法 ,在低频和高频区域内获得了具有较大禁带的两种二维光子晶体 .低频区域内 ,找到具有最大禁带宽度的光子晶体的禁带宽度为Δω =0 0 76 (2πc a) ,中心频率... 详细信息

采用一种改进的平面波展开法 ,运用一种有效的设计二维各向异性光子晶体的方法 ,在低频和高频区域内获得了具有较大禁带的两种二维光子晶体 .低频区域内 ,找到具有最大禁带宽度的光子晶体的禁带宽度为Δω =0 0 76 (2πc a) ,中心频率为 0 76 9(2πc a) (这里的a为晶格常量 ) .高频区域内 ,找到的光子晶体的最大禁带宽度为Δω =0 1(2πc α) ,中心频率为 1 6 5 3(2πc a) .同时在低频区域内 ,发现一种很简单的正方网格结构 ,它的禁带宽度为Δω =0 0 5 74 (2πc a) ,禁带宽度与禁带的中心频率之比为Δω ωc =11 782 % .

关键词：低频高频大禁带光子晶体平面波展开法各向异性材料完全禁带介质周期结构电磁波

MULTIPLICITY-PRESERVING TRIANGULAR SET DECOMPOSITION OF TWO POLYNOMIALS

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Journal of Systems Science & Complexity 2014年第6期27卷 1320-1344页

作者： CHENG Jin-san GAO xiao-Shan Key Laboratory of Mathematics Mechanization Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of Sciences

In this paper, a multiplicity-preserving triangular set decomposition algorithm is proposed for a system of two polynomials, which involves only computing the primitive polynomial remainder sequence of two polynomials once and certain GCD computations. The algorithm decomposes the unmixed variety defined by two polynomials into square free and disjoint （for non-vertical components, see Definition 4） algebraic cycles represented by triangular sets which may have negative multiplicities. Thus, the authors can count the multiplicities of the non-vertical components. In the bivariate case, the amthors give a complete algorithm to decompose tile system into zeros represented by triangular sets with multiplicities. The authors also analyze the complexity of the algorithm in the bivariate ease. The authors implement the algorithm and show the effectiveness of the method with extensive experiments.

关键词： Algebraic cycle multiplicity-preserving primitive polynomial remainder sequence trian-gular set decomposition.

Entanglement of Two-Qubit Quantum Heisenberg XYZ Chain

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Chinese Physics Letters 2002年第8期19卷 1044-1047页

作者： Xi xiao-Qiang, Hao san-Ru Institute of Modern Physics Northwest University Fundamental Department Xi"an Institute of Posts and Telecommunications

We derive the analytic expression of the concurrence in the quantum Heisenberg XYZ model and discuss the influence of parameters J, Δ and Γ on the concurrence. By choosing different values of Γ and Δ, we obtain the XX, XY, XXX and XXZ chains. The concurrence decreases with increasing temperature. When T→0, the concurrence reaches its maximum value 1, i.e. the entangled state, |Ψ> = (((2)^1/2)/2)(|01>-|10>), is maximum entanglement. For the XXZ chain, when , the concurrence will meet its maximum value Cmax = (sinh (1/T))/(cosh (1/T)).

关键词： Chains

Thermal Entanglement of an XY Two-Qutrit Spin Chain with Dzialoshinski—Moriya Interaction

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Communications in Theoretical Physics 2009年第11期52卷 825-828页

作者： MA xiao-san WANG An-Min School of Electric Engineering and Information Anhui University of Technology Ma＇anshan 243002 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China

The effect of Dzialoshinski-Moriya(DM)interaction on thermal entanglement of an XY two-qutrit spinchain is *** find that DM interaction and the anisotropy parameter can enhance quantum thermal entanglementto a maximal value ***,when both of them take large values,the entanglement is notenhanced,but is *** analysis will shed some light on the understanding of the effect of the DM interactionon thermal entanglement of an XY two-qutrit spin chain.

关键词： thermal entanglement XY spin chain DM interaction

Geometric Phases Corrected by Stochastic Dephasing

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Communications in Theoretical Physics 2008年第5期49卷 1179-1181页

作者： MA xiao-san WANG An-Min Department of Modern Physics University of Science and Technology of China Hefei 230026 China

We analyze the effect of stochastic dephasing on geometric phases. The result implies that the correction of geometric phases relies on not only the fluctuation of the random variable in the stochastic process, but al... 详细信息

关键词： stochastic dephasing geometric phase

Meta label associated loss for fine-grained visual recognition

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Science China(Information Sciences) 2024年第6期67卷 230-247页

作者： Yanchao LI Fu xiao Hao LI Qun LI shui YU School of Computer Science Nanjing University of Posts and Telecommunications School of Network Engineering Zhoukou Normal University School of Computer Science University of Technology Sydney

Recently, intensive attempts have been made to design robust models for fine-grained visual recognition, most notably are the impressive gains for training with noisy labels by incorporating a reweighting strategy into a meta-learning framework. However, it is limited to up or downweighting the contribution of an instance for label reweighting approaches in the learning process. To solve this issue, a novel noise-tolerant method with auxiliary web data is proposed. Specifically, first, the associations made from embeddings of well-labeled data with those of web data and back at the same class are measured. Next, its association probability is employed as a weighting fusion strategy into angular margin-based loss, which makes the trained model robust to noisy datasets. To reduce the influence of the gap between the well-labeled and noisy web data, a bridge schema is proposed via the corresponding loss that encourages the learned embeddings to be coherent. Lastly, the formulation is encapsulated into the meta-learning framework, which can reduce the overfitting of models and learn the network parameters to be noise-tolerant. Extensive experiments are performed on benchmark datasets, and the results clearly show the superiority of the proposed method over existing state-of-the-art approaches.

关键词： label associated loss weighting noisy samples fine-grained visual recognition noise-tolerant learning meta-learning

Characterization of the protein expression and localization of hnRNP family members during murine spermatogenesis

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Asian Journal of Andrology 2023年第3期25卷 314-321页

作者： xiao-Li Wang Jin-Mei Li shui-Qiao Yuan Institute of Reproductive Health Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Laboratory of Animal Center Huazhong University of Science and TechnologyWuhan 430030China Shenzhen Huazhong University of Science and Technology Research Institute Shenzhen 518057China

Mammalian testis exhibits remarkably high transcriptome complexity,and spermatogenesis undergoes two periods of transcriptional *** make the RNA-binding proteins(RBPs)the utmost importance during male germ cell *** nuclear ribonucleoproteins(hnRNPs)are a large family of RBPs implicated in many steps of RNA processing;however,their roles in spermatogenesis are largely ***,we investigated the expression pattern of 12 hnRNP family members in mouse testes and found that most detected members are highly expressed in the ***,we found that most of the detected hnRNP proteins(hnRNPD,hnRNPK,hnRNPQ,hnRNPU,and hnRNPUL1)display the highest signals in the nuclei of pachytene spermatocytes,round spermatids,and Sertoli cells,whereas hnRNPE1 exclusively concentrates in the manchette of elongating *** expression of these hnRNP proteins showed both similarities and specificity,suggesting their diverse roles in spermatogenesis.

关键词： gene expression heterogeneous nuclear ribonucleoproteins mice Sertoli cells spermatogenesis