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Determination of minimum flood flow for regeneration of floodplain forest from inundated forest width-stage curve

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Water Science and Engineering 2010年第3期3卷 257-268页

作者： song-hao SHANG Xiao-min MAO State Key Laboratory of Hydroscience and Engineering Department of Hydraulic Engineering Tsinghua University Beijing 100084 P. R. China College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 P. R. China

Floods are essential for the regeneration and growth of floodplain forests in arid and semiarid regions. However, river flows, and especially flood flows, have decreased greatly with the increase of water diversion from rivers and/or reservoir regulation, resulting in severe deterioration of floodplain ecosystems. Estimation of the flood stage that will inundate the floodplain forest is necessary for the forest＇s restoration or protection. To balance water use for economic purposes and floodplain forest protection, the inundated forest width method is proposed for estimating the minimum flood stage for floodplain forests from the inundated forest width-stage curve. The minimum flood stage is defined as the breakpoint of the inundated forest width-stage curve, and is determined directly or analytically from the curve. For the analytical approach, the problem under consideration is described by a multi-objective optimization model, which can be solved by the ideal point method. Then, the flood flow at the minimum flood stage （minimum flood flow）, which is useful for flow regulation, can be calculated from the stage-discharge curve. In order to protect the forest in a river floodplain in a semiarid area in Xinjiang subject to reservoir regulation upstream, the proposed method was used to determine the minimum flood stage and flow for the forest. Field survey of hydrology, topography, and forest distribution was carried out at typical cross sections in the floodplain. Based on the survey results, minimum flood flows for six typical cross sections were estimated to be between 306 m3/s and 393 m3/s. Their maximum, 393 m3/s, was considered the minimum flood flow for the study river reach. This provides an appropriate flood flow for the protection of floodplain forest and can be used in the regulation of the upstream reservoir.

关键词： floodplain forest regeneration flow minimum flood stage inundated forest width method ideal point method

A Combined Numerical-Experimental Study on the Noise Power Spectrum Produced by an Electromagnetic Sensor for Slurry Flow

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Fluid Dynamics & Materials Processing 2021年第3期17卷 511-529页

作者： song Gao Xin Jin Qiaohong Liu College of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang471023China School of Medical Instruments Shanghai University of Medicine and Health SciencesShanghai201318China

The signals generated by electromagnetic flow sensors used for slurry fluids are often affected by noise interference produced by interaction with the slurry *** this study,the power spectrum characteristics of the signal are studied,and an attempt is made to determine the relationship between the characteristics of the related noise and the velocity and concentration of the slurry *** experiments are conducted and the related power spectrum curve is obtained processing the signal measured by the sensor with *** simulations are also carried out in the frame of an Eulerian approach in order get additional insights into the considered problem through comparison with the experimental *** following conclusions are drawn:(1)The intensity of noise is directly proportional to the number of solid particles colliding with the electrode of the electromagnetic flow sensor per unit time,and to the square of the average velocity of the flow layer near the pipe wall.(2)With an increase in the slurry noise intensity,the power spectrum curve shifts upward in the logarithmic coordinate system(and vice versa).

关键词： Electromagnetic flow sensor slurry noise power spectrum kinetic energy theorem

Multi-SymplecticWavelet Collocation Method for Maxwell’s Equations

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Advances in Applied Mathematics and Mechanics 2011年第6期3卷 663-688页

作者： Huajun Zhu songhe song Yaming Chen Department of Mathematics and System Science School of ScienceNational University of Defense TechnologyChangsha 410073China

In this paper,we develop a multi-symplectic wavelet collocation method for three-dimensional(3-D)Maxwell’s *** the multi-symplectic formulation of the equations,wavelet collocation method based on autocorrelation functions is applied for spatial discretization and appropriate symplectic scheme is employed for time *** analysis shows that the proposed method is multi-symplectic,unconditionally stable and energy-preserving under periodic boundary *** numerical dispersion relation is *** with splitting scheme,an explicit splitting symplectic wavelet collocation method is also *** experiments illustrate that the proposed methods are efficient,have high spatial accuracy and can preserve energy conservation laws exactly.

关键词： Multi-symplectic wavelet collocation method Maxwell’s equations symplectic conservation laws

Landing route planning method for micro drones based on hybrid optimization algorithm

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Biomimetic Intelligence & Robotics 2021年第1期1卷 26-30页

作者： Liang Shaoran song Bifeng Xue Dong School of Aeronautics Northwestern Polytechnical UniversityXi’anChina

Aiming at the obstacle avoidance trajectory planning problem in the landing process of the micro drone,this paper proposes a swarm optimization algorithm that combines the dragonfly optimization method and the differential evolution *** orthogonal learning mechanism is adopted to realize the adaptive switch between the two *** the process of landing route planning,the planning plane is first obtained by making the gliding plane tangent to the *** the planning plane,the projection of obstacle is transformed into multiple unreachable line *** designing an optimization model,the 3D landing route planning problem is transformed into a 2D obstacle avoidance route optimization *** the shortest route as the optimization objective,the penalty factor is introduced into the cost function to avoid the intersection of the landing route and *** the optimization process,through the orthogonal learning of the intermediate iterative results,the hybrid algorithm can adaptively select the next iterative algorithm,so it can give full play to the respective advantages of the two *** optimization results show that,compared with the single optimization algorithm,the hybrid optimization algorithm proposed in this paper can better solve the problem of landing route planning for micro-small UAVs.

关键词： Route planning Micro drones Dragonfly optimization Hybrid optimization

cDNA cloning, functional expression and cellular localization of rat liver mitochondrial electron-transfer flavoprotein-ubiquinone oxidoreductase protein

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Science China(Life Sciences) 2005年第4期48卷 357-367页

作者： HUANG Shengbing song Wei LIN Qishui Key Laboratory of Molecular Cell Biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China

A membrane-bound protein was purified from rat liver *** being di-gested with V8 protease,two peptides containing identical 14 amino acid residue sequences were *** the 14 amino acid peptide derived DNA sequence as gene specific primer,the cDNA of correspondent gene 5′-terminal and 3′-terminal were obtained by RACE *** full-length cDNA that encoded a protein of 616 amino acids was thus cloned,which included the above mentioned peptide *** full length cDNA was highly homologous to that of human ETF-QO,indicating that it may be the cDNA of rat ***-QO is an iron sulfur protein located in mitochondria inner membrane containing two kinds of redox center:FAD and[4Fe-4S]*** comparing the sequence from the cDNA of the 616 amino acids protein with that of the mature protein of rat liver mitochondria,it was found that the N terminal 32 amino acid residues did not exist in the mature protein,indicating that the cDNA was that of *** the cDNA was expressed in Saccharomyces cerevisiae with inducible vectors,the protein product was enriched in mitochondrial fraction and exhibited electron transfer activity(NBT re-ductase activity)of *** demonstrated that the 32 amino acid peptide was a mito-chondrial targeting peptide,and both FAD and iron-sulfur cluster were inserted properly into the expressed ***-QO had a high level expression in rat heart,liver and *** fu-sion protein of GFP-ETF-QO co-localized with mitochondria in COS-7 cells.

关键词： electron transfer flavoprotein ubiquinone oxidoreductase precursor rat protein purification gene clone tissuespecificity.

Numerical Simulation of Fluid Membranes in Two-Dimensional Space

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Communications in Computational Physics 2008年第4期3卷 794-821页

作者： Peng song Dan Hu Pingwen Zhang LMAM and School of Mathematical Sciences Peking UniversityBeijing 100871China.

The membrane’s dynamics is very important for cells.A membrane in 2-dimensional space can be seen as an incompressible closed curve in a plane or a cylindrical surface in 3-dimensional *** this paper,we design a second-order accurate numerical algorithm to simulate the shape transformation of the *** the algorithm,we use the tangent angles to present the curve and avoid the difficulties from the constraint of curve’s incompressible condition.A lot of interesting phenomena are *** of them are very like the life processes of cells,such as exocytosis and ***,we can see the relation between two dynamic models *** last,considering the influence of the inner incompressible fluids partially,we add a constraint:the area circled by the membrane maintain *** numerical results show the dynamic motions of a curve remaining its local arc length and inner area constant.

关键词： Director model of the membrane reduced model osmotic pressure spontaneous curvature constraint of the area.

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迁移学习在医学图像分类中的研究进展

中国图象图形学报 2022年第3期27卷 672-686页

作者：黎英宋佩华南宁师范大学广西人机交互与智能决策重点实验室南宁530001

医学影像作为医疗数据的主要载体,在疾病预防、诊断和治疗中发挥着重要作用。医学图像分类是医学影像分析的重要组成部分。如何提高医学图像分类效率是一个持续的研究问题。随着计算机技术进步,医学图像分类方法已经从传统方法转到深度... 详细信息

医学影像作为医疗数据的主要载体,在疾病预防、诊断和治疗中发挥着重要作用。医学图像分类是医学影像分析的重要组成部分。如何提高医学图像分类效率是一个持续的研究问题。随着计算机技术进步,医学图像分类方法已经从传统方法转到深度学习,再到目前热门的迁移学习。虽然迁移学习在医学图像分类中得到较广泛应用,但存在不少问题,本文对该领域的迁移学习应用情况进行综述,从中总结经验和发现问题,为未来研究提供线索。1)对基于迁移学习的医学图像分类研究的重要文献进行梳理、分析和总结,概括出3种迁移学习策略,即迁移模型的结构调整策略、参数调整策略和从迁移模型中提取特征的策略;2)从各文献研究设计的迁移学习过程中提炼共性,总结为5种迁移学习模式,即深度卷积神经网络(deep convolution neural network,DCNN)模式、混合模式、特征组合分类模式、多分类器融合模式和二次迁移模式。阐述了迁移学习策略和迁移学习模式之间的关系。这些迁移学习策略和模式有助于从更高的抽象层次展现迁移学习应用于医学图像分类领域的情况;3)阐述这些迁移学习策略和模式在医学图像分类中的具体应用,分析这些策略及模式的优点、局限性及适用场景;4)给出迁移学习在医学图像分类应用中存在的问题并展望未来研究方向。

关键词：医学图像图像分类迁移学习迁移学习策略迁移学习模式

Ultrasonic measurements of single-crystal gold under hydrostatic pressures up to 8 GPa in a Kawai-type multi-anvil apparatus

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Chinese Science Bulletin 2007年第12期52卷 1600-1606页

作者： song MaoShuang Akira YONEDA Eiji ITO Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Institute for Study of the Earth Interior Okayama University Misasa Tottori-ken 683-0193 Japan

Ultrasonic measurements were conducted on single-crystal gold at ambient condition and hydrostatic pressures up to 8 GPa at room temperature in a Kawai-type multi-anvil apparatus. The P-wave velocities measured at high pressures were in good agreement with Daniels and Smith’s ultrasonic study. The three independent elastic constants of gold at ambient condition were determined to be C11=192.7 GPa, C12=162.9 GPa, and C44=42.4 GPa. On the basis of an analysis of previous elastic data and the present ultrasonic data, the pressure derivatives of three elastic constants were estimated to be C1 ′1= 7.12,C 1′2 = 6.24,and C4′4 = 1.82. The calculated values of isothermal bulk modulus (KT0) and its pressure derivatives ( KT ′0) are KT0 = 166.44 GPa and KT ′0= 6.56. This indicates that Anderson et al.’s model of equation of state of gold might underestimates pressure about 1 GPa at pressure around 23 GPa and ambient temperature. Our results explained the discrepancies among the models of equation of state of gold proposed previously.

关键词：单晶体黄金超声波测量高温高压实验流体静力学状态方程

COUPLING ANALYSES OF FRAGILE ECO-ENVIRONMENT IN THE WEST OF THE songNEN PLAIN

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Chinese Geographical Science 2001年第3期11卷 61-67页

作者： Chang-chun song Wei Deng Xin-shan song Zhao-qing Luan Changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China

The fragile eco-environment is a special type of ecosystem,its response to the change of environmental condi -tions is very *** it is rather prone to be disturbed under unfav orable *** activity h as greatly changed the geo-chemical process in the ecosystem,thus caused a series o f positive and negative *** t he ecosys-tem,especially in the fragile eco-e nvironment,different systems and r egimes are interconnected and *** the suntainable development of ecosystem and the protection and rational utilization of resources,it is of great impor-tance to study these internal relati onships and seek rational regulatio n and control *** paper tak es the fragile eco-environment in the west of the songnen Plain as an *** on th e study of the topograph,physiognom y,soil,vegetation and their geographic distribution in the landscape,th e paper explains the structure of the ecologic land-scape and quantifies the ecologic ge o-chemical processes under differe nt landscape *** additio n,the paper al-so tries making coupling analyses of the ecologic succession and the landscape geochemical *** in the pa-per,some research results are given.

关键词： west of the songnen Plain fragile eco-environment ecologic structure coupling of ecologic factors