化学结构的计算机处理（Ⅲ）：立体化学的贮存与检索

目前应用最广泛的基于连接表的化学结构表述方法本质上只适于表述这分子的拓扑、即只能考虑分子原子间的连接关系，而不能描述它们在空间中的排布，然而，两上具有相同原子拓年的分子，在三维空间听真实结构可能是不相同的，其性质也 相同，这种现象称为分子结构的立体化学、衫和的计算机化学结构描述方法必须能处理立体化学、本文简要地综述了基于连接表的手性中心和双键立体化学的描述方法。     

模糊非线性奇偶方程故障诊断方法

研究基于模糊模型和奇偶(一致性)方程的非线性系统执行器故障诊断方法.讨论了全 解耦奇偶方程的产生方法,并给出了全解耦奇偶向量存在的条件.由全解耦奇偶方程产生的残 差仅对特定执行器故障敏感,而与系统状态、扰动输入和其它执行器输入无关.用T-S模糊模型 描述非线性系统,并与全解耦奇偶方程相结合得到了模糊奇偶方程,解决了奇偶方程在非线性 系统中的应用问题.将执行器故障模型用刻度因子和偏差表示,用模糊奇偶方程产生残差,从而 可以估计故障模型的参数.文章给出了某飞机非线性模型的仿真实例.     

一种立体空间布局模型及布局算法

本文首先讨论了空间布局的同态变换求解思想，分析了基于长方体的立体布局的空间关系，借助图论中的某些概念，建立了一种立体空间布局模型ＳＯＳＧ图，给出了该模型表达立人本空间布局的完备性与封闭性。本文还讨论了基于该模型的布局算法，简要介绍了该方法在计算机结构布局中的应用。     

奇偶交换排序算法性能的研究

文中给出了实现奇偶交换排序策略的一种算法,并对该算法进行了算法分析和实验测试结果的讨论,在此基础上,提出了奇偶交换排序算法的应用建议。     

CA与生命游戏演化的组合模型*

基于摩尔奇偶型CA,提出一种结合生命游戏的演化模型.首先设置初始构型进行摩尔奇偶型规则演化,再引入生命游戏规则,按游戏规则演化;最后依此重复摩尔奇偶规则和生命游戏规则,直到演化整个元胞空间.证实在摩尔奇偶型CA的基础上,结合生命游戏在很大程度上减小了演化过程对初始构型的依赖,出现更为丰富的图元以及基于图元和演化框架的动态图案,且演化过程仍然符合摩尔奇偶型CA的演化规律.结合模型可以避免演化过度依赖初始构型以及演化过程的单调性,而且组合演化模型可以应用于图案生成,生成保持风格的规则几何纹理图案,丰富图案的生成方法.     

L-丙交酯和D,L-丙交酯共聚物立体化学构型的计算机模拟

运用Monte Carlo法,模拟D,L-丙交酯(DLLA)与L-丙交酯(LLA)共聚体系,在不同投料比情况下的立体化学构型,计算了两种立体异构体在共聚高分子链中所占的比例,与各种异构体序列的长度分布;计算了轮数R;分析了竞聚率r和投料比p对DLLA-LLA共聚物的立体化学结构的影响,发现r直接影响立体异构序列的交替程度;计算了共聚链上四单元组和六单元组的含量,引用文献提供的13C NMR谱图进行验证;研究了共聚组成、重均序列长度等模拟结果与某些物性实验数据之间的关系,发现共聚物的结晶速率和一定范围内的重均序列长度有关。     

立体二叉树及其应用

文章提出了立体二叉树的数据结构,对立体二叉树的基本概念和性质进行了讨论;对满立体二叉树结构的结点分布和结点编码之和问题进行了研究并给出了有关的公式;最后探讨了立体二叉树在分类中的应用,提出了立体堆的分类方法,并对它的算法实现进行设计与分析,得出了立体堆分类方法在最坏情况下的时间复杂性,从而减少了堆分类方法的时间复杂性的常数因子。     

一种用于立体感增强的SFS改进算法

表面重建是计算机立体视觉中的一个重要研究领域,SFS(shape from shading)是单帧图像立体感增强的有效方法之一。为了更好地利用SFS对图像进行增强,在对朗伯体表面反射模型进行详细分析和对影响3维重建结果的关键因素进行讨论的基础上,提出了一种改进的SFS算法,并给出了具体的步骤和计算方法。实验表明,该算法的确改善了立体显示的效果。     

计算机视觉技术在根系形态和构型分析中的应用解析

基于对计算机视觉技术在根系形态和构型分析中应用的研究,首先,阐述计算机视觉技术基本内容。然后,分析计算机视觉技术在根系形态和构型分析中的应用现状。最后,给出根系形态和构型分析中,计算机视觉技术的应用,包括图像分割技术的应用、细化技术的应用等。     

雷达维修训练模拟器中的虚拟测量方法

文章提出了虚拟测量的设计思想，详细讨论了虚拟测量的实现方法，将该方法应用到雷达维修训练模拟器中，形象地对显示在计算机屏幕上的雷达组合电路板块进行信号波形、电压、电流、电阻的测量，并将结果显示在计算机屏幕上。     

Probabilistic voxel mapping using an adaptive confidence measure of stereo matching

In this paper, we describe a probabilistic voxel mapping algorithm using an adaptive confidence measure of stereo matching. Most of the 3D mapping algorithms based on stereo matching usually generate a map formed by point cloud. There are many reconstruction errors. The reconstruction errors are due to stereo reconstruction error factors such as calibration errors, stereo matching errors, and triangulation errors. A point cloud map with reconstruction errors cannot accurately represent structures of environments and needs large memory capacity. To solve these problems, we focused on the confidence of stereo matching and probabilistic representation. For evaluation of stereo matching, we propose an adaptive confidence measure that is suitable for outdoor environments. The confidence of stereo matching can be reflected in the probability of restoring structures. For probabilistic representation, we propose a probabilistic voxel mapping algorithm. The proposed probabilistic voxel map is a more reliable representation of environments than the commonly used voxel map that just contains the occupancy information. We test the proposed confidence measure and probabilistic voxel mapping algorithm in outdoor environments.     

Generalized parallel-perspective stereo mosaics from airborne video

In this paper, we present a new method for automatically and efficiently generating stereoscopic mosaics by seamless registration of images collected by a video camera mounted on an airborne platform. Using a parallel-perspective representation, a pair of geometrically registered stereo mosaics can be precisely constructed under quite general motion. A novel parallel ray interpolation for stereo mosaicing (PRISM) approach is proposed to make stereo mosaics seamless in the presence of obvious motion parallax and for rather arbitrary scenes. Parallel-perspective stereo mosaics generated with the PRISM method have better depth resolution than perspective stereo due to the adaptive baseline geometry. Moreover, unlike previous results showing that parallel-perspective stereo has a constant depth error, we conclude that the depth estimation error of stereo mosaics is in fact a linear function of the absolute depths of a scene. Experimental results on long video sequences are given.     

The Space of All Stereo Images

A theory of stereo image formation is presented that enables a complete classification of all possible stereo views, including non-perspective varieties. Towards this end, the notion of epipolar geometry is generalized to apply to multiperspective images. It is shown that any stereo pair must consist of rays lying on one of three varieties of quadric surfaces. A unified representation is developed to model all classes of stereo views, based on the concept of a quadric view. The benefits include a unified treatment of projection and triangulation operations for all stereo views. The framework is applied to derive new types of stereo image representations with unusual and useful properties. Experimental examples of these images are constructed and used to obtain 3D binocular object reconstructions.     

Stereo and Alternating-Pair Techniques for Display of Computer-Generated Images

Electro-optical stereo pair displays and alternating-pair displays are both viable methods for true 3-D representation of computer-generated images.     

GLSV: Graphics library stereo vision for OpenGL

This work proposes the development of an auxiliary library for use with OpenGL, to facilitate the creation of graphic applications incorporating stereoscopic representation. This library, christened graphics library stereo vision (GLSV), is designed to remove all calculations involving knowledge of stereo vision theory from the task performed by the programmer without the latter having to change the way he/she has been working with the OpenGL library. The GLSV is distributed under the terms of the GNU Library General Public License agreement.     

On adjustment of stereo parameters in multiview synthesis for planar 3D displays

This paper investigates the impacts of stereo parameters in multiview synthesis for planar 3D display and presents a novel parameter adjustment method for reducing visual discomforts and geometric distortions. The proposed method combines the geometry of stereoscopic capturing system with the comfortable viewing rules for the human vision system in three steps. First, an identically sized representation between the virtual space and the display space is established, and the virtual camera parameters are derived based on the stereo geometry. Second, the scale factor between the physical space and the virtual space is computed based on the depth of focus theory to diminish vergence–accommodation conflicts. Last, the capturing and displaying parameters are adjusted according to the comfortable viewing zone and personal preference. Experimental results demonstrated that a reliable basis for multiview image synthesis and a more comfortable stereo perception can be achieved by applying the proposed method.     

Noise Reduction in Surface Reconstruction from a Given Gradient Field

We present a gradient space technique for noise reduction in surfaces reconstructed from a noisy gradient field. We first analyze the error sources in the recovered gradient field of a surface using a three-image photometric stereo method. Based on this analysis, we propose an additive noise model to describe the errors in the surface gradient estimates. We then use a vector space formulation and construct a multiscale orthonormal expansion for gradient fields. Using the sparse representation properties of this expansion, we develop techniques for reducing the gradient field noise by coefficient selection with thresholding. The simulation results indicate that the proposed technique provides significant improvement on the noise levels of both the estimated gradient fields and the reconstructed surfaces under heavy noise levels. Furthermore, the experiments using noisy photometric stereo image triplets of real range data suggest that the additive model remains viable after the nonlinear photometric stereo operation to provide accurate noise removal.     

A stereo matching paradigm based on the Walsh transformation

Describes a new feature-based stereo matching technique which exploits the Walsh transformation. The established matching strategy adopts and integrates the fundamental steps of the stereo vision problem: (a) detecting and locating feature points, (b) searching for potential matches, (c) validating a match through a global consistency check, and (d) determining the disparity of the matched feature points. The unique representation of stereo images into Walsh-based attributes unites the aforementioned steps into an integrated process which yields accurate disparity extraction. It is shown that the first and second Walsh attributes are used as operators approximating the first and second derivatives for the extraction and localization of feature points. The complete set of these attributes are then used as matching primitives contributing equally to the decision-making process and providing relevant information on both the characterization of a potential match and its validation through a consistency check. Computer results using images of varying complexities prove the soundness and the relatively fast processing time of this stereo matching technique     

Computer graphics for cellular reconstruction

The use of computer graphics to study the three-dimensional structure of tissues within an organism such as a human is considered. A system called Sterecon, which uses stereo views of thick sections of tissues and a high-voltage electron microscope, is described. Contours of structures are traced in stereo and entered into a graphics database. Using thick sections decreases the work by ten- to twenty-fold. The database can be manipulated to display cellular organization using various graphics representations