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RATE OF CONVERGENCE OF SCHWARZ ALTERNATING METHOD FOR TIME-DEPENDENT CONVECTION-DIFFUSION PROBLEM

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Journal of Computational Mathematics 2002年第5期20卷 479-490页

作者： Jian-wei hu Cai-hua Wang School of Mathematical Sciences Nankai University300071 Tianjin China Laboratory of Computational Physics IAPCM100088 Beijing China Department of Mathematics Tianjin Normal University300073 Tianjin China

Presents a study that examined the application of an overlapping domain decomposition method to the solution of time-dependent convection-diffusion problems. Background on the Schwartz alternating procedure; Applicati... 详细信息

关键词： rate of convergence Schwarz alternating method convection-diffusion problem

Synthesis and Characterization of Zirconia Nanocrystallites by Cationic Surfactant and Anionic Surfactant

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1133-1139页

作者： YU Jian-Chang hu Sheng-wei College of Material Science and Engineering Fuzhou University Fuzhou 350002 China

Study on nanomaterials has attracted great interests in recent years. In this article, zirconia nanocrystallites of different structures have been successfully synthesized via hydrothermal methods with cationic surfactant （CTAB） and anionic surfactant （SDS）, respectively. Differential Scanning Calorimeter （DSC-TG）, X-ray Diffractometer （XRD）, Transmission Electron Microscope （TEM）, Ultraviolet-Visible （UV-vis） and N2 adsorption-desorption analyses are used for their structure characteristics. The results show that the cationic surfactant has a distinctive direction effect on the formation of zirconia nanocrystallites, while the anionic surfactant has a self-assembly synergistic effect on them. The sample synthesized with the cationic surfactant presents good dispersion with the main phase of tetragonal zirconia, and the average nanocrystal size is around 15 nm after calcination at 500 ℃. While the sample synthesized with the anionic surfactant exhibits a worm-like mesoporous structure with pure tetragonal phase after calcination at 500 ℃ and with good thermal stability.

关键词： cationic surfactant anionic surfactant zirconia nanocrystallites,mesoporous zirconia

Elliptic curve with Optimal mixed Montgomery-Edwards model for low-end devices

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Science China(Information Sciences) 2015年第11期58卷 67-74页

作者： LIU Zhe hu Zhi WU wei University of Luxembourg School of Mathematics and Statistics Central South University School of Mathematics and Computer Science Fujian Normal University

This paper introduces a special family of twisted Edwards curve named Optimal mixed MontgomeryEdwards(OME) curves. The OME curve is proposed by exploiting the fact that every twisted Edwards curve is birationally equivalent to some elliptic curve in Montgomery form. The OME curves achieve optimal group arithmetic for both of twisted Edwards model and Montgomery model. In particular, the Montgomery model of OME curves only requires 3M + 2S and 1M + 3S + 3C to perform the point addition and point doubling operations, while 7M and 3M + 4S are needed for executing a point addition and point doubling for the twisted Edwards model of them. We also make effort to carefully choose the curve parameters and the underlying implementation field to achieve high performance. An example of OME curve is E /Fp:-x2+y2= 1-27822·x2y2over p = 2192- 264- 1. Our implementation results on the widely used 8-bit micro-controller platforms(i.e.,AVR Atmega128) further demonstrate and highlight the practical benefits of proposed OME curve on low-end device. In particular, our implementation, performed in constant-time, reduces the execution time by up to14% and 18% for fixed point and random point scalar multiplication, respectively, when comparing with the state-of-the-art implementation on the identical platform.

关键词： cryptography elliptic curve scalar multiplication efficient implementation 8-bit AVR processors

Quantitative Geoscience and Geological Big data Development： A Review

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1490-1515页

作者： CHEN Jianping XIANG Jie hu Qiao YANG wei LAI Zili hu Bin wei wei School of Earth Sciences and Resources China University of Geosciences Beijing 100083 Beijing Land and Resources Information Research and Development Key Laboratory Beijing 100083

After long-term development, mathematical geology has today become an independent discipline. Big data science, which has become a new scientific paradigm in the 21st century, gives rise to the geological Big data, i.e. mathematical geology and quantitative geoscience. Thanks to a robust macro strategy for big data, China＇s quantitative geoscience and geological big data＇s rapid development meets present requirements and has kept up with international levels. This paper presents China＇s decade-long achievements in quantitative prediction and assessment of mineral resources, geoscience information and software systems, geological information platform development, etc., with an emphasis on application of geological big data in informatics, quantitative mineral prediction, geological environment and disaster management, digital land survey, digital city, etc. Looking ahead, mathematical geology is moving towards ＂Digital Geology＂, ＂Digital Land＂ and ＂Geological Cloud＂, eventually realizing China＇s grand ＂Digital China＂ blueprint, and these valuable results will be showcased on the international academic arena.

关键词： mathematical geology big data geological big data digital land

Water on silicene： A hydrogen bond-autocatalyzed physisorption-chemisorption-dissociation transition

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Nano Research 2017年第7期10卷 2223-2233页

作者： wei hu Zhenyu Li Jinlong Yang Hefei National Laboratory for Physical Sciences at Microscale Department of Chemical Physics and Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China Hefei 230026 China Computational Research Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA

A single water molecule is nothing special. However, macroscopic water displays many anomalous properties at interfaces, such as hydrophobicity and hydrophilicity. Although the underlying mechanisms remain elusive, hydrogen bonds between water molecules are expected to play a major role in these interesting phenomena. An important question concerns whether water clusters containing few molecules are qualitatively different from a single molecule. Using the water adsorption behavior as an example and by carefully choosing two-dimensional silicene as the substrate material, we demonstrate that water monomers, dimers, and trimers show distinct adsorption properties at the substrate surface. On silicene, the additional water molecules in dimers and trimers induce a transition from physisorption to chemisorption and then to dissociation, arising from the enhancement of charge transfer and proton transfer processes induced by hydrogen bonding. Such a hydrogen bond autocatalytic effect is expected to have broad applications in metal-free catalysis for the oxygen reduction reaction and water dissociation.

关键词： hydrogen bond silicene physisorption chemisorption dissociation density functional theory

Postulation of Leaf Rust Resistance Genes in Seven Chinese Spring Wheat Cultivars

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Journal of Integrative Agriculture 2013年第9期12卷 1580-1588页

作者： SHI Li-hong ZHANG Na hu Ya-ya wei Xue-jun YANG Wen-xiang LIU da-qun Department of Plant Pathology College of Plant Protection/Biological Control Center for Plant Diseases and Plant Pests of HebeiAgricultural University of Hebei

To detect the leaf rust resistance genes in the 7 Chinese spring wheat clultivars Shenmian 99025, Shenmia 99042, Shenmian 85, Shenmian 91, Shenmian 96, Shenmian 1167 and Shenmian 962, Thatcher, Thatcher backgrounded near-isogenic lines and 15 pathotypes of P. triticina were used for gene postulate at the seedling stage, and 9 of the 15 pathotypes were used in the field tests. Molecular markers closely linked to, or co-segregated with resistance genes Lrl, Lr9, LrlO, Lrl9, Lr20, Lr21, Lr24, Lr26, Lr28, Lr29, Lr32, Lr34, Lr35, Lr37, Lr38, and Lr47 were screened to assist detection of the resistance genes. As results, 4 known resistance genes, including Lrl, Lr9, Lr26, and Lr34, and other unknown resistance genes were postulated singly or in combination in the tested cultivars. Shenmian 85, Shenmian 91, Shenmian 96, Shenmian 962, Shenmian 1167, and Shenmian 99042 are potentially useful for wheat production and breeding programs. The result suggested that combining gene postulation, molecular markers and pedigrees is effective and more accuracy method to know the resistance genes in cultivars.

关键词： gene postulation molecular marker Triticum aestivum Puccinia triticina resistance gene

Identification of QTLs associated with cadmium concentration in rice grains

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Journal of Integrative Agriculture 2018年第7期17卷 1563-1573页

作者： hu da-wei SHENG Zhong-hua LI Qian-long CHEN wei wei Xiang-jin XIE Li-hong JIAO Gui-ai SHAO Gao-neng WANG Jian-long TANG Shao-qing hu Pei-song State Key Laboratory of Rice Biology Ministry of Science and Technology/Key Laboratory of Rice Biology and Breeding Ministry of Agriculture/China National Rice Research Institute College of Agronomy Hunan Agricultural University

Cadmium（Cd） contamination in rice has been a hot topic of research because of its potential risk to human health. In this study, a double haploid（DH） population derived from Zhongjiazao 17（YK17）（an early-season indica cultivar）×D50（a tropical japonica cultivar） was used to identify quantitative trait loci（QTLs） associated with Cd concentration in brown rice（CCBR） and Cd concentration in milled rice（CCMR）. Continuous and wide variation for CCBR and CCMR were observed among the DH population. Correlation analysis revealed a positive and highly significant correlation between the two traits. A total of 18 QTLs for CCBR and 14 QTLs for CCMR were identified in five different pot and field trials. Two pairs of QTLs for CCBR（qCCBR2-1 and qCCBR2-2, qCCBR9-1 and qCCBR9-2） and one pair of QTLs for CCMR（qCCMR5-1 and qCCMR5-2） were detected in multiple trials. The alleles increasing CCBR at the qC CBR2-1/qC CBR2-2 and qC CBR9-1/qC CBR9-2 QTLs were contributed by YK17 and D50, respectively, whereas the D50 allele at the qCCMR5-1/qCCMR5-2 QTLs increased CCMR. Eight pairs of QTLs for CCBR and CCMR, qCCBR2-2 and qCCMR2-2, qCCBR3 and qCCMR3, qCCBR4-2 and qCCMR4-1, qCCBR4-3 and qCCMR4-2, qCCBR4-4 and qCCMR4-3, qCCBR5 and qCCMR5-2, qCCBR7 and qCCMR7, and qCCBR11-1 and qCCMR11-2, co-localized on chromosomes 2, 3, 4, 5, 7, and 11, respectively. For all of these QTL pairs, except qCCBR5/qCCMR5-2, the additive effects came from YK17. In addition, four CCMR QTLs showing significant additive×environment interaction and two pairs of CCMR QTLs with bi-allelic epistatic interactions were identified. The results of this study could facilitate marker-assisted selection of breeding rice varieties with low Cd accumulation in grain.

关键词： Cd concentration in grain QTL mapping brown rice milled rice

Effectively modeling piecewise planar urban scenes based on structure priors and CNN

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Science China(Information Sciences) 2019年第2期62卷 206-210页

作者： wei WANG wei GAO Zhanyi hu School of Network Engineering Zhoukou Normal University National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences University of Chinese Academy of Sciences

Dear editor,Piecewise planar stereo methods can approximately reconstruct the complete structures of a scene by overcoming challenging difficulties (e.g.,poorly textured regions) that pixel-level stereos appear powerless. In general, these methods have three basic steps:(1) over-segmenting the image into several regions (superpixels) without overlapping;(2) generating candidate planes from initial 3D points;(3) assigning the optimal plane for each superpixel using a global method. However,

关键词： Effectively modeling piecewise planar urban scenes based on structure priors and CNN Hs MRF

First-principles kinetics study of carbon monoxide promoted Ostwald ripening of Au particles on FeO/Pt(111)

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Journal of Energy Chemistry 2019年第3期28卷 108-113页

作者： Sulei hu Runhai Ouyang wei-Xue Li State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Department of Chemical Physics School of Chemistry and Materials ScienceiCHeMCAS Excellence Center for NanoscienceUniversity of Science and Technology of ChinaHefei 230026AnhuiChina Hefei National Laboratory for Physical Sciences at the Microscale Hefei 230026AnhuiChina University of Chinese Academy of Sciences Beijing 100049China

The dynamic and kinetic evolution of supported metal particles in the presence of reactants is decisive in shaping the nature of the catalytic active sites and the deactivation process. Ostwald ripening of FeO/Pt(111) supported Au particles in the presence of carbon monoxide is addressed here by firstprinciples kinetics. It is found that CO stabilizes the ripening monomer(Au atom) by forming favorable Au carbonyls with lower total activation energy, and corresponding phase diagram at wide range of temperature and CO pressures is constructed. Evolution of particle number, dispersion and particle size distribution of supported Au particles are explored. Great influence of CO promotion on ripening kinetics is revealed and explored in details, and mbar range of CO can lower the onset temperature of ripening by a few hundred kelvins. The present work reveals the crucial role of the metal-reactant complexes formed under reaction conditions on ripening of metal catalysts.

关键词： Carbon monoxide Au particles Ostwald ripening First-principles kinetics FeO/Pt(111)