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Learning a hierarchical image manifold for Web image classification

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第10期13卷 719-735页

作者： Rong ZHU Min YAO li-hua ye Jun-ying XUAN School of Information Engineering Jiaxing UniversityJiaxing 314001China School of Computer Science and Technology Zhejiang UniversityHangzhou 310027China

Image classification is an essential task in content-based image ***,due to the semantic gap between low-level visual features and high-level semantic concepts,and the diversification of Web images,the performance of traditional classification approaches is far from users' *** an attempt to reduce the semantic gap and satisfy the urgent requirements for dimensionality reduction,high-quality retrieval results,and batch-based processing,we propose a hierarchical image manifold with novel distance measures for *** that the images in an image set describe the same or similar object but have various scenes,we formulate two kinds of manifolds,object manifold and scene manifold,at different levels of semantic *** manifold is developed for object-level classification using an algorithm named extended locally linear embedding(ELLE) based on intra-and inter-object difference *** manifold is built for scene-level classification using an algorithm named locally linear submanifold extraction(LLSE) by combining linear perturbation and region *** results show that our method is effective in improving the performance of classifying Web images.

关键词： Web image classification Manifold learning Image manifold Semantic granularity Distance measure

Site Occupation of Nb in γ-TiAI:Beyond the Point Defect Gas Approximation

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Acta Metallurgica Sinica(English Letters) 2019年第12期32卷 1511-1520页

作者： Wei Diao li-hua ye Zong-Wei Ji Rui Yang Qing-Miao Hu Institute of Metal Research Chinese Academy of SciencesWenhua Road 72Shenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaJinzhai Road 96Hefei 230026China University of Chinese Academy of Sciences Yuquan Road 19ABeijing 100049China

Microalloying is an effective approach to improve the mechanical properties of γ-TiAl intermetallic *** about the site occupancy of the ternary alloying element in the crystal lattice ofγ-TiAl is highly demanded in order to understand the physics underlying the alloying *** first-principle methods-based thermodynamic models for the determination of the site occupancy were based on the point defect gas approximation with the interaction between the point defects *** the present work,we include the point defect interaction energy in the thermodynamic model,which allows us to predict the site occupancy of the ternary alloying element inγ-TiAl beyond the point defect gas *** model is applied to theγ-TiAl-Nb *** show that,at low temperature,the site occupancy of Nb atoms depends on the composition of the alloy:Nb atoms occupy the A1 sublattice for the Ti-rich alloy but occupy Ti sublattice for the Al-rich *** fraction of Nb atoms occupying A1 sublattice in the Ti-rich alloy decreases drastically,whereas the fraction of Nb atoms on the Ti sublattice in the Al-rich alloy decreases slightly with increasing *** high temperature,Nb atoms occupy dominantly the Ti sublattice for both the Ti-rich and Al-rich *** interaction between the point defects makes the Ti sublattice more favorable for the Nb atoms to occupy.

关键词： Site preference Titanium aluminides Special quasi-random structures First principles method

Structural characteristics and mechanism of hydrogen-induced disproportionation of the ZrCo alloy

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International Journal of Minerals,Metallurgy and Materials 2012年第11期19卷 1010-1015页

作者： Xiu-mei Guo Shu-mao Wang Xiao-peng liu Zhi-nian li Jian-hua ye Hui-ping Yuan li-jun Jiang Energy Material and Technology Institute General Research Institute for Nonferrous Metals Beijing 100088 China

The intermetallic compound ZrCo was prepared, and its hydrogen-induced disproportionation in hydrogen desorption processes was investigated. The hydrogenation-dehydrogenation thermodynamics of the ZrCo alloy was evaluated by pressure-composition isotherm measurements at different temperatures. The kinetic processes of hydrogen-induced disproportionation at different temperatures under certain pressures were detailedly studied. The disproportionation rate of the ZrCo alloy increased with the increases of temperature and initial hy- drogen pressure under experimental conditions. However, the maximum attainable extent of disproportionation did not change much with an increase in temperature or initial hydrogen pressure. The crystallographic structure analysis of the ZrCo alloy combining with its corre- sponding dehydrogenation kinetic curves under the conditions of an initial hydrogen pressure of 0.2 MPa and a temperature of 723 K indi- cated that the basic process of disproportionation reactions was composed of four stages： rapid dehydrogenation of ZrCoH3, equilibrium of dehydrogenation, simultaneity of dehydrogenation and disproportionation, and completion of disproportionation.

关键词： zirconium compounds cobalt compounds hydrogenation dehydrogenation structural analysis thermodynamics

China top brand strategy and innovation

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Chinese Business Review 2007年第5期6卷 37-41,65页

作者： ZHAO Jian-hua li Yan ye Jian liU Yi School of Economics and Management China Three Gorges University Yichang 443002 China

The Chinese economy appears the double-restraint characteristic at present stage including mainly resources restraint and market restraint. With the policy of reform and opening up, and especially after accelerating the two fundamental changes put forward by central government, the transformation of the economic growth mode achieved positive progress in China. There was still no brand from China mainland belonging to the 100 top world valuable brands according to Business Weekly of America in 2006. By 2007, a total of 1957 China top brand, 10 world famous China top brand are awarded in china to form a powerful enterprise group. But how to assess a brand is still troublesome. This paper shows the evolution of the policy and discusses the dilemma expecting the advice from the domestic and abroad.

关键词： China top brand strategy innovation

Cascade quantum teleportation

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Optoelectronics Letters 2006年第6期2卷 455-458页

作者： ZHOU Nan-run GONG li-hua liU ye Department of Electronics Information Engineering Nanchang University Nanchang 330029 China

In this letter a cascade quantum teleportation scheme is *** proposed scheme needs less local quantum operations than those of quantum multi-teleportation.A quantum teleportation scheme based on entanglement swapping is presented and compared with the cascade quantum teleportation *** two schemes can effectively teleport quantum information and extend the distance of quantum communication.

关键词：叶栅量子运输纠缠交换技术量子无线电物理

非金属原子边缘修饰InSe纳米带的磁电子学特性及应变调控

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物理学报 2019年第19期68卷 287-296页

作者：李野华范志强张振华柔性电子材料基因工程湖南省重点实验室长沙理工大学物理与电子科学学院

利用基于密度泛函理论的第一性原理计算方法,研究了Se边用H饱和、In边用各种非金属元素X(X=H,B,N,P,F和Cl)端接的锯齿型In Se纳米带(H-ZN(7)-X)的几何结构、磁电子特性及应变效应.计算的形成能和Forcite退火模拟表明H-ZN(7)-X具有稳定... 详细信息

利用基于密度泛函理论的第一性原理计算方法,研究了Se边用H饱和、In边用各种非金属元素X(X=H,B,N,P,F和Cl)端接的锯齿型In Se纳米带(H-ZN(7)-X)的几何结构、磁电子特性及应变效应.计算的形成能和Forcite退火模拟表明H-ZN(7)-X具有稳定的几何结构.F和Cl端接时,纳米带具有和H端接时类似的磁金属性质.N端接时,纳米带磁性最强.但B和P端接使得纳米带边缘的磁性完全消失.特别是,我们发现外加的机械应变可以增强H-ZN(7)-N磁稳定性,并且有效地调节费米能级处的自旋极化率(SP),能在0-92%之间变化,这意味着可设计机械开关来控制低偏压下的自旋输运.应变调制机制与应变诱导的键长变化导致不成对的电子的重新分布或消失有关.N-ZN(7)-N的磁性主要来源于In,Se及N原子的p轨道,这对于研发非过渡金属磁性材料有重要意义.

关键词： InSe 纳米带非金属原子磁电子学特性应变效应

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 192-201页

作者： Shuai li Zhen Ma Jin-hua Gao School of Science Hebei University of Science and Technology School of Electronics and Information Zhengzhou University of Light Industry School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and Technology

We theoretically investigate the spin resolved Friedel oscillation （FO） and quasiparticle interference （QPI） in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r-2in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as *** spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment (***ález-Herrero et al.,Science 352,437 （2016）).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states （FT-LDOS）.Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

Prussian Blue Analogue‑Templated Nanocomposites for Alkali‑Ion Batteries:Progress and Perspective

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Nano-Micro Letters 2025年第1期17卷 216-261页

作者： Jian‑En Zhou Yilin li Xiaoming lin Jiaye ye Key Laboratory of Theoretical Chemistry of Environment Ministry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006People’s Republic of China School of Chemistry and Physics Faculty of ScienceQueensland University of Technology2 George StreetBrisbaneQLD 4000Australia Centre for Materials Science Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia

lithium-ion batteries(liBs)have dominated the portable electronic and electrochemical energy markets since their commercialisation,whose high cost and lithium scarcity have prompted the development of other alkali-ion batteries(AIBs)including sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs).Owing to larger ion sizes of Na^(+)and K^(+)compared with li^(+),nanocomposites with excellent crystallinity orientation and well-developed porosity show unprecedented potential for advanced lithium/sodium/potassium *** enticing open rigid framework structures,Prussian blue analogues(PBAs)remain promising self-sacrificial templates for the preparation of various nanocomposites,whose appeal originates from the well-retained porous structures and exceptional electrochemical activities after thermal *** review focuses on the recent progress of PBA-derived nanocomposites from their fabrication,lithium/sodium/potassium storage mechanism,and applications in AIBs(liBs,SIBs,and PIBs).To distinguish various PBA derivatives,the working mechanism and applications of PBA-templated metal oxides,metal chalcogenides,metal phosphides,and other nanocomposites are systematically evaluated,facilitating the establishment of a structure–activity correlation for these *** on the fruitful achievements of PBA-derived nanocomposites,perspectives for their future development are envisioned,aiming to narrow down the gap between laboratory study and industrial reality.

关键词： Prussian blue analogues Self-sacrificial template lithium-ion batteries Sodium-ion batteries Potassium-ion batteries

Relationship Between Several Biochemical Indexes and Resistance of Aegilops Species to Oat-Bird Cherry Aphids(Homoptera:Aphididae)

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Agricultural Sciences in China 2003年第9期2卷 994-999页

作者： li Qing, ye hua zhi, YANG Qun fang and JIANG Su rong (College of Agronomy, Sichuan Agricultural University, Yaan 625014, P.R.China) College of Agronomy Sichuan Agricultural University Yaan 625014 P.R.China

The biochemical mechanism of resistance of 9 Aegilops species including ***,***, ***, *** var. varianilis, ***, ***, ***, *** and *** in Triticeae to oat bird cherry aphid ( Rhopalosiphum padi ) were reported for the first time. The results showed that the content of total phenols in seedling was not associated with resistance to this aphid. The level of DIMBOA was negatively related to intrinsic innate rate of increase ( r m ) of R. padi. Neither of soluable sugar nor total phenols in adult stage was associated with resistance level. However, concentrations of free proline and serine in leaf were positively related to r m of R. padi ( r m =0.0636+0.23x pro ** +1.982x ser *). The content of DIMBOA was high negatively related to r m of R. padi ( r =0.819 ** ). The low level of free proline and serine and high concentration of DIMBOA could be regarded as important elements for resistance of Aegilops species to R. padi.

关键词： Aegilops Resistance mechanism Rhopalosiphum padi