扫描线多边形区域填充算法研究

在CAD系统中,经常需要对封闭区域进行填充,对于一个功能完善的CAD系统而言,区域填充算法是十分重要的内容,同时该算法也是图形学的基本算法之一．单连通多边形是解决复杂区域填充问题的基础,从扫描线区域填充的原理、数据结构的设计、算法实现等几个方面进行了详细的分析．     

BGI注入式种子填充算法及实现

区域填充问题在ＣＡＤ、科学可视化、图形图象处理等领域均有着广泛和深入的应用，研究高效的区域填充算法，是计算机图形学的重要问题之一。多边形填充算法只适用于多边形区域的填充，边界填充算法虽然对区域边界形状无严格要求，但要求区域边界颜色特征一致。为此，提出一个注入式区域填充算法，对于内点定义的区域，不要求边界颜色特征一致，在此基础上，对ＴｕｒｂｏＣ和ＢｏｒｌａｎｄＣ＋＋的图形库函数进行了扩充。该算法及其实现给相关图形的处理带来了极大的方便     

复杂多边形的填充算法

概述区域填充中两两类常用算法－－扫描转换和种子填充和基本思想及其性能。结合两类算法的设计思想，给出了一个复杂多边形的填充算法，并用ＴＵＲＢＯ ＰＡＳＣＡＬ加以实现。     

复杂地质构造的等值线填充及实现

本文实现了一种基于局部多边形的复杂地质构造等值线图的填充算法.算法基本思想是:先对矩形网格的顶点值采用两段法估计,然后把断层线作为约束条件,将矩形网格划分为若干个的三角形网格,最后在三角形网格内完成等值线的追踪和填充.研究实例表明,该算法在油藏描述可视化中有很好的显示与应用效果.     

多边形填充硬件算法的研究与实现

提出一种多边形填充的硬件算法,并通过在Xilinx公司生产的Vertex2 Pro实验板上进行验证,证明该算法的可行性及其良好高效性.     

多边形链式编码方式的改进及其编码方法

由于链式编码以每个区域为单位存储边界,相邻区域的边界被重复存储,所以通过索引机制来检查是否存在多余的多边形,从而避免相邻边界被重复保存。基于多边形拓扑关系的算法,对多边形图形链式编码方式提出了一种改进算法,采用二叉树编码、霍夫曼原理,将链式编码进行了重新编码并转换成可运算的多边形矢量编码,实现了多边形图形的叠置运算功能,同时提高了链式编码方式的数据压缩效率。     

边标志算法实现过程中的常见问题及解决方法

0 引言 区域填充问题是计算机图形学当中的一个基本问题,在图形学的各个应用领域都经常会遇到,主要是研究如何对指定区域内的像素赋予特定的颜色代码.目前常见的区域填充算法可分为基于多边形的填充,基于边的填充及种子填充算法等3种.     

多边形裁剪的新算法——多边形与窗口相互裁剪法

多边形裁剪是计算机图形处理及辅助设计的典型课题之一。国内外已发表的多边形剪裁法已有多种。本文提出的多边形与矩形窗口之间互为裁剪窗口进行裁剪的一种算法，它不需要进行任何判别就能实现多边形裁剪。算法的特点是计算方法简便、计算速度快、占用内存少、应用方便。这种算法已在IBM——PC机上运行，并取得良好效果。它还可应用于有关2维几何造型及装配图绘制的CAD软件包巾。     

地空导弹武器系统仿真中目标与设定区域(多边形)位置关系判别算法

将地空导弹武器系统仿真中诸多问题抽象为目标与设定区域(多边形)位置关系判别问题。提出旋转函数和相关边的概念,设计了判断目标在多边形内外的新算法。综合运用旋转函数与相关边技术,将目标与多边形之间的位置关系转化为目标与其相关边之间的位置关系,首先找出目标点的相关边,再计算该点与其相关边组成的有向三角形的旋转函数,最后利用旋转函数值的正负性来判断目标与多边形的位置关系。在相关边的寻找过程中设计了算法,避免了大量的求交运算,从根本上提高了算法的效率。新算法还简单有效地解决了传统判别算法——射线法中的临界位置问题。程序验证表明：新算法易于实现,适用于简单多边形,在地空导弹武器系统仿真中具有很强的重用性,对避免重复的仿真研究和开发具有重要意义。     

平面多边形简单性确定及其定向算法

给出了一个确定平面多边形为简单多边形的实用算法，同时，又给出了简单多边形为顺时针或逆时针走向的充要条件，利用这些条件，可较好地解决简单多边形走向判断的问题，且易于实现。     

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     

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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Brief Introduction to “Journal of Jilin University( Science Edition) ”

<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has