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CONVERGENCE OF INNER ITERATIONS SCHEME OF THEDISCRETE ORDINATE METHOD IN SPHERICAL GEOMETRY

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Journal of Computational Mathematics 2005年第3期23卷 321-326页

作者： zhi-junShen guang-weiYuan Long-junShen LaboratoryofComputationalPhysics InstituteofAppliedPhysicsandComputationalMathematicsP.O.Box8009Beijing100088China

In transport theory, the convergence of the inner iteration scheme to the spherical neutron transport equation has been an open problem. In this paper, the inner iteration for a positive step function scheme is consid... 详细信息

关键词： transport equation discrete ordinate inner iteration

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土工合成材料加筋垫层的应用研究

山东大学学报（工学版） 2003年第5期33卷 568-571页

作者：付志前王广月姜萍孙加明山东大学土建与水利学院山东济南250061

分析了常用的土工合成材料加筋垫层承载力方法所体现的加筋机理 ,提出了改进的加筋垫层承载力计算方法。

关键词：土工合成材料加筋垫层地基处理

The redshift number density evolution of Mg Ⅱ absorption systems

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Research in Astronomy and Astrophysics 2013年第6期13卷 641-650页

作者： zhi-fu Chen Department of Physics and Telecommunication Engineering Baise University Center for Astrophysics Guangzhou University

We make use of the recent large sample of 17 042 Mg Ⅱ absorption systems from Quider et al. to analyze the evolution of the redshift number density. Regardless of the strength of the absorption line, we find that the evolution of the redshift number density can be clearly distinguished into three different phases. In the intermediate redshift epoch （0.6 ≤ z ≤ 1.6）, the evolution of the redshift number density is consis- tent with the non-evolution curve, however, the non-evolution curve over-predicts the values of the redshift number density in the early （z ≤ 0.6） and late （z ≥ 1.6） epochs. Based on the invariant cross-section of the absorber, the lack of evolution in the red- shift number density compared to the non-evolution curve implies the galaxy number density does not evolve during the middle epoch. The fiat evolution of the redshift number density tends to correspond to a shallow evolution in the galaxy merger rate during the late epoch, and the steep decrease of the redshift number density might be ascribed to the small mass of halos during the early epoch.

关键词： methods: statistical -- galaxies: evolution -- quasars: absorption lines

Single View Based Measurement on Space Planes

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Journal of Computer Science & Technology 2004年第3期19卷 374-382页

作者： guang-HuiWang Zhan-YiHu fu-ChaoWu NationalLaboratoryofPatternRecognition InstituteofAutomationTheChineseAcademyofSciencesBeijing100080P.R.China

The plane metrology using a single uncalibrated image is studied in the paper, and three novel approaches are proposed. The first approach, namely key-line-based method, is an improvement over the widely used key-point-based method, which uses line correspondences directly to compute homography between the world plane and its image so as to increase the computational accuracy. The second and third approaches are both based on a pair of vanishing points from two orthogonal sets of parallel lines in the space plane together with two unparallel referential distances, but the two methods deal with the problem in different ways. One is from the algebraic viewpoint which first maps the image points to an affine space via a transformation constructed from the vanishing points, and then computes the metric distance according to the relationship between the affine space and the Euclidean space, while the other is from the geometrical viewpoint based on the invariance of cross ratios. The second and third methods avoid the selection of control points and are widely applicable. In addition, a brief description on how to retrieve other geometrical entities on the space plane, such as distance from a point to a line, angle formed by two lines, etc., is also presented in the paper. Extensive experiments on simulated data as well as on real images show that the first and the second approaches are of better precision and stronger robustness than the key-point-based one and the third one, since these two approaches are fundamentally based on line information.

关键词： single view metrology projective geometry geometrical parameter retrieval plane homography

Two-dimensional vanadium nanosheets as a remarkably effective catalyst for hydrogen storage in MgH_(2)

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Rare Metals 2021年第11期40卷 3195-3204页

作者： zhi-Yu Lu Hai-Jie Yu Xiong Lu Meng-Chen Song fu-Ying Wu Jia-guang Zheng zhi-Fei Yuan Liu-Ting Zhang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China Analysis and Testing Center Jiangsu University of Science and TechnologyZhenjiang 212003China

Magnesium hydride(MgH_(2)),which possesses high hydrogen density of 7.6 wt%,abundant resource and non-toxicity,has captured intense attention as one of the potential hydrogen storage ***,the practical application of Mg/MgH_(2) system is suffering from high thermal stability,sluggish absorption and desorption ***,two-dimensional(2D) vanadium nanosheets(V_(NS)) were successfully prepared via a facile wet chemical ball milling method and proved to be highly effective on improving the hydrogen storage performance of MgH_(2).For instance,the MgH_(2)+7 wt% V_(NS) composite began to release hydrogen at 187.2℃,152 ℃ lower than that of additive-free MgH_(2).At 300℃,6.3 wt% hydrogen was released from the MgH_(2)+7 wt% V_(NS) composite within 10 *** addition,the fully dehydrogenated sample could absorb hydrogen even at room temperature under hydrogen pressure of 3.2 MPa.X-ray diffractometer(XRD) and transmission electron microscopy(TEM)results confirmed metallic vanadium served as catalytic unit for facilitating the de/rehydrogenation reaction of MgH_(2).This finding presents an example of facile synthesis of two-dimensional(2D) vanadium with excellent catalysis,which may shed light on future design and preparation of highly effective layered catalysts for hydrogen storage and other energy-related areas.

关键词： Hydrogen storage Magnesium hydride Two-dimensional vanadium nanosheets Catalytic effect

Engineering DNA Materials for Sustainable Data Storage Using a DNA Movable-Type System

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Engineering 2023年第10期29卷 130-136页

作者： Zi-Yi Gong Li-fu Song guang-Sheng Pei Yu-Fei Dong Bing-zhi Li Ying-Jin Yuan Frontiers Science Center for Synthetic Biology&Key Laboratory of Systems Bioengineering(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China School of Biomedical Informatics The University of Texas Health Science Center at Houston(UTHealth)HoustonTX 77030USA

DNA molecules are green materials with great potential for high-density and long-term data ***,the current data-writing process of DNA data storage via DNA synthesis suffers from high costs and the production of hazards,limiting its practical ***,we developed a DNA movable-type storage system that can utilize DNA fragments pre-produced by cell factories for data *** this system,these pre-generated DNA fragments,referred to herein as“DNA movable types,”are used as basic writing units in a repetitive *** process of data writing is achieved by the rapid assembly of these DNA movable types,thereby avoiding the costly and environmentally hazardous process of de novo DNA *** this system,we successfully encoded 24 bytes of digital information in DNA and read it back accurately by means of high-throughput sequencing and decoding,thereby demonstrating the feasibility of this *** its repetitive usage and biological assembly of DNA movable-type fragments,this system exhibits excellent potential for writing cost reduction,opening up a novel route toward an economical and sustainable digital data-storage technology.

关键词： Synthetic biology DNA data storage DNA movable types Economical DNA data storage

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矩形基础下加筋砂土地基承载力的研究

山东大学学报（工学版） 2003年第1期33卷 60-68页

作者：付志前王广月侯岱云车强山东大学土建与水利学院山东省济南市250061 山东大学基建处滨州市化工工程监理所

本文通过对矩形基础下的土工格栅加筋砂土地基进行有限元法分析 ,并与模型试验结果进行比较 ,得出加筋砂土地基比无加筋砂土地基的极限承载力有显著的提高 ,探讨了加筋地基中最上层筋材距基底的深度 ,筋材的竖向间距、层数和尺寸等几何... 详细信息

本文通过对矩形基础下的土工格栅加筋砂土地基进行有限元法分析 ,并与模型试验结果进行比较 ,得出加筋砂土地基比无加筋砂土地基的极限承载力有显著的提高 ,探讨了加筋地基中最上层筋材距基底的深度 ,筋材的竖向间距、层数和尺寸等几何参数对加筋地基的极限承载力的影响 ,并且提出了各几何参数砂土的最佳值。

关键词：地基承载力矩形基础/土工格栅加筋砂土

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