识别判断手绘三角形的类型

为了实现手绘三角形的识别和分类,本文提出了一种手绘三角形的识别分类方法。采用确定笔迹首末点、消除伪角点,最后进行笔迹分割和直线拟合的方式进行手绘三角形的识别,然后模式识别中的几何图形识别来对手绘三角形的类型进行判别,将三角形分为等腰三角形、直角三角形、等腰直角三角形、等边三角形和任意三角形。实验证明该方法有效解决了手绘三角形中小勾和晃动的影响,从而实现了三角形的重建和分类。     

导航星三角形分类选取算法研究

为减小星三角形的冗余度,生成三角形数量最少、分布均匀性好的导航星三角形信息表,提出了一种以支持向量机为基础的导航星三角形选取优化算法．该算法通过一种以统计学习理论为基础的支持向量机寻求最优决策分类面,在由导航星表所生成的三角形中提取导航星三角形．实验结果表明,本算法所生成的导航星三角形表中的星三角形数量少,所需存储空间小,空间分布均匀性良好．     

透析向量与三角形的交汇点

本文主要从利用向量加减法运算三角形形状、向量关系式与三角形各种心的关系、向量的数量积与三角形的关系以及三角形的性质与向量的定比分点的关系等几个方面论述了向量与三角形的几个交汇点。     

椭圆型偏微分方程的三角形单元有限元的数值解法

本文以椭圆型偏微分方程问题为背景研究三角形单元的有限元方法.随着计算机图形学的发展,三角形单元划分取得了巨大的成就,可以得到质量非常好的三角形单元,进而提高偏微分方程的有限元方法的数值解的精度.本文采用节点增量算法,对问题区域进行三角形单元划分,得到的三角形单元满足Delaunay条件,再对三角形单元的所有节点采用自适应编号,最后运用三角形单元的有限元方法得到椭圆型偏微分方程的数值解.通过数值实验,得出相比传统的三角形单元的有限元方法,本文的三角形单元的有限元方法减小了舍入误差,提高了计算精度.     

三角形爷爷的生日宴会

正又是一年一度的重阳节,正巧赶上图形王国里德高望重的三角形爷爷过生日。三角形家族里有一对好兄弟等腰三角形和等边三角形,他们约好一块儿去给三角形爷爷拜寿。两人来到三角形爷爷家时,几乎所有的家族成员都到齐了,正在谈论各种话题。他俩急忙向三角形爷爷问好,然后依次和其     

双曲类二次曲线外切2n+1边形中有向面积的定值定理及其应用

利用有向面积定值法,对双曲线外切2n+1边形中切顶线三角形和对角线三角形进行研究,得到双曲线外切2n+1边形中切顶线三角形有向面积的定值定理以及双曲线外切五边形中切顶线三角形和对角线三角形有向面积的定值定理及其若干推论,其中包括射影几何中著名的Brianchon定理在双曲线外切三角形和五边形中的情形.     

广义杨辉三角形与Lucas数列的关系研究

把杨辉三角形推广到广义杨辉三角形,将广义杨辉三角形与Lucas数列结合,得出了以广义杨辉三角形中某一行为系数的、连续几个Lucas数的和的简洁计算公式。     

含有两个分离三角形的极大平图有一个Hamilton路

一个图若包含Hamilton圈，则这个图是Hamilton图．Whitney已经证明了没有分离三角形的极大平图是Hamilton图．一个三角形若删去其顶点后使图不连通，则这个三角形称为分离三角形。Chuiyuan Chen证明了仅含有一个分离三角形的极大平图仍然是Hamilton图，我们将证明含有两个分离三角形的极大平图有一个Hamilton路。     

抛物线外切2n+1边形中向面积的定值定理及其应用

利用有向面积定值法,对抛曲线外切2n 1切顶线三角形和对角线三角形进行研究,得到抛曲线外切2n 1边形中切顶线三角形有向面积的定值定理以及抛曲线外切五边形中切顶线三角形和对角线三角形有向面积的定值定理及其若干推论,其中包括射影几何中著名的Brianchon定理在抛曲线外切三角形和五边形中的情形.     

寻找全等三角形“六法”

利用全等三角形的性质可以证明分别属于两个三角形中的线段或角相等.在证明线段或角相等时,解题的关键往往是根据条件找到两个可能全等的三角形,再证明这两个三角形全等,最后得出结论.下面介绍六种寻找全等三角形的方法,供同学们参考.     

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.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

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