实测数据驱动的小型植物三维重建研究

以小型植物为对象,根据植物的形态结构特点,采用三维数字化技术获取植物主干和枝条的空间信息,重建植物枝干骨架拓扑结构模型;然后以植物器官的三维网格模型为模板,结合不同器官在植物上的生长规律,实现植物形态结构的精细三维重建.实验结果表明,该方法能较好地实现不同类型小型植物不同生长时期植株形态结构的多分辨率三维重建,用户可以根据需要调整三维模型的精细程度,从而为开展植物株型分析研究、植物品种展示及植物三维资源库开发等应用提供了简单、灵活的技术.     

篌竹出笋成竹生长规律研究

对篌竹生长规律进行了研究。结果表明,篌竹出笋时间约始于4月8日,历时约32d,出笋初期出笋少,盛期、末期出笋数较多,但末期持续时间较长,退笋率随着笋期的推移先不断增加后下降。砍伐样方的成竹率比未砍伐样方的高。较早同生群幼竹高生长遵循逻辑斯蒂曲线方程,而较晚同生群幼竹高生长符合指数函数曲线方程,较早同生群的高度高于较晚同生群。     

基于空间结构的杉木枝下高可视化模拟研究

【目的】定量研究林分空间结构对杉木枝下高的影响,构建基于空间结构的枝下高模型,结合杉木生长模型,应用三维可视化技术,实现杉木枝下高可视化模拟。【方法】利用湖南省黄丰桥国有林场6块杉木人工林临时样地的调查数据,选择5个常用枝下高基础模型,分析水平空间结构参数(P_H)、垂直空间结构参数(P_V)和空间结构单元平均距离(d_DIS)及其组合对枝下高的影响,构建综合指标较好且变量少的枝下高模型。基于林分三维模型实时生成方法,建立一种枝干可控的杉木三维模型;结合单木胸径连年生长量模型、树高-曲线模型和冠幅面积估计模型,模拟林木的生长状态。【结果】Logistic模型综合指标较好且模型参数可解释,可选为基础模型;3个空间结构参数中垂直空间结构影响较为显著,将P_V加入到Logistic模型中,改善了枝下高模型的拟合效果,决定系数(R²)从0.717提升到0.741,估计值的标准差从1.407 m减小到1.321 m,并使各项模型检验误差指标有所减小;构建的杉木三维模型可以动态调节枝干,实现了杉木枝下高模拟。【结论】构建的枝下高模型可以应用于林木年龄和部分林分信息未知的杉木林中,体现了林木间的相互竞争影响;结合枝干可控的杉木三维模型,模拟杉木生长过程,形象直观地表现了杉木枝下高的变化,为进一步研究林分生长动态可视化模拟和森林经营可视化模拟提供支持。     

火龙果花和果实的动态发育规律研究

本研究观察了火龙果花朵和果实完整的动态发育过程,测量了其花的长度、宽度和重量等指标以及其果实的纵向直径、横向直径、重量等指标.结果表明:本研究建立了夏季火龙果花从冒芽到开花共20天的动态生长曲线,获得了花发育相关指标的动态规律;建立了果实从授粉结束到果实成熟共30天的动态生长曲线,获得了果实发育相关指标的动态规律.本研究结果可为火龙果的杂交育种及火龙果的施肥、灌溉和采收等种植管理提供理论参考.     

基于像散的并行全场三维检测新方法

基于像散原理，提出了一种全场并行三维检测新方法，该检测方法利用微透镜阵列产生的二维点光源阵列来实现并行像散光路，实现了对测量表面的全场同步检测．利用像散特性曲线中的线性关系，实现在较大采样间距下获得较高的轴向分辨率．介绍了并行全场三维检测的测量原理，对像散光学系统的性能参数和影响因素进行了分析和讨论，并进行了可行性实验．实验结果中像散特性与理论分析是基本吻合的，表明像散法在并行三维检测中可以应用．     

中国杉王整枝复壮后新枝生长研究

生长在贵州省习水县太坪村的中国杉王，栽植于宋代，距今己800多年，其树高达44．8米，胸径达238厘米，冠幅达21米，主干立木蓄积达88．94立方米，由于多年管理工作未及时跟上，出现了严重的顶端部份腐烂、枝干干枯、树冠部份出现病虫危害、枝叶发黄，新枝萌发明显减少，呈现出严重的树体老化现象。在2007年至2008年期间，经过多方面的调查、分析，研究，编制了《中国杉王整枝复壮工程实施方案》，经过综合治理，中国杉王新发枝的生长情况特别明显，通过采枝取样检测与附近不同树龄与林木当年新枝检测数据表明：经过整枝复壮技术处理后，取得了非常明显的成效。     

界面扩散控制晶粒生长动力学的计算机模拟

建立一个模拟晶粒生长过程的三维计算机模型，利用该模型可以方便地模拟不同条件下的晶粒生长过程，对不同温 度、体积分数和激活能条件下的生长过程进行了模拟运算结果表明：三维晶粒尺寸ｒ随时间ｔ演化的生长过程满足关系ｒ－ｔ＾１／ｎ，ｎ的值约为６，该模型的计算机模拟对纳米相生长动力学等实验具有一定的理论预见的指导意义。     

环形磁控溅射成膜生长速率及厚度均匀性研究

对目前广泛用于制备高Ｔｃ超导薄膜的环形磁控溅射成膜提出了一种新的理论模型，采用泰勒展开计算出了三阶近似的解析结果，通过计算机作出了薄膜生长速率及厚度均匀性随薄膜位置变化关系的三维曲线，得到了生长大面积均匀薄膜、快速生长薄膜的最佳位置，并同使用较广泛的平面磁控溅射的一些计算结果进行了比较。     

制冷工质R11池沸腾换热气泡行为的可视化研究

采用可视化实验技术对压力为0.1MPa的条件下、制冷工质R11池沸腾气泡行为进行了深入观察和分析．可视化实验结果表明，气泡底部微液层的蒸发对气泡的生长具有极其重要的作用．在气泡生长过程中，未发现气泡底部的微液层有液体补充．研究结果表明，随着壁面过热度的升高，气泡脱离直径与脱离时间减小，而气泡脱离频率升高．此外，通过对实验图像资料的分析，得到了气泡直径及气泡底部干斑直径随时间的变化曲线以及沸腾表面汽化核心密度随热流变化的关联式．基于实验结果，利用动态微液层模型对制冷工质R11的池沸腾曲线进行了预测，结果显示，预测值与实验值在高热流密度条件下符合较好．     

基于ArcGISEngine的洪水淹没三维可视化研究

在ArcGIS软件中,不能直接创建Multipatch模型,但是可以通过ArcGISEngine编程实现或导入其他建模软件的模型、本文以GIS的shapefile数据为基础,在skeethup中建立区域三维地形、房屋、植被等要素模型。采用水文动力的基本原理计算河道水位．并用C#结合ArcGISEngine创建水面TIN模型,利用ArcsceneControl控件创建三维场景,叠加三维地形仿真模型与水面TIN模型,对洪水演进模拟进行了可视化研究,实现了基于ArcGISEngine的洪水淹没三维可视化动态模拟。为利用AE,完成洪水淹没三维可视化研究提供了一种逼真的、简便有效的方法。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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