基于投影匹配的目标姿态测量方法研究

提出一种在图像投影匹配基础上进行的目标姿态测量新方法,避免了传统姿态测量中左右像面目标的特征匹配或灰度匹配.二维投影相关法是基于二维投影的灰度相关匹配算法,主要利用匹配图像相邻像素的灰度值的大小关系应该相同的原理进行图像匹配.在此基础上采用双目视觉测量空间轴对称目标姿态,应用面面交会法获取轴对称目标在像面的轴线,进行三维姿态测量.模拟实验结果表明:该方法姿态角测量误差小于0.2°;且计算速度快,结果稳定,能够满足处理的要求.     

空间轴对称目标三维姿态测量方法的研究

提出一种双目视觉测量空间轴对称目标姿态的新方法,应用线性方法获取轴对称目标在像面的轴线,通过两像面轴线与各自光心所成的平面相交,得到被测目标的轴线的方向矢量,进行三维姿态测量,避免了传统姿态测量中左右像面目标特征点的特征匹配或灰度匹配。模拟实验结果表明:该方法姿态角测量误差小于0.5°;且计算速度快,结果稳定,能够满足实时处理的要求。     

基于改进ORB算法的双目视觉定位测量方法

针对基于传统特征点检测的双目视觉测量中匹配时间长、误匹配率高和测量精度低的问题,提出了基于改进ORB算法的双目视觉定位测量方法。首先对特征点邻域内的像素点灰度值进行加权,再采用灰度质心法提取特征点的主方向,最后以字符串描述子代替传统二进制描述子对特征点进行描述,在测量中采用二维二次函数精确拟合特征点的亚像素坐标,实验结果表明,该改进方法在特征点匹配正确率和测量精度上都有很大的提升,特征点匹配正确率提升了31.8%,测量最低误差达到0.42%,满足双目视觉测量的精度要求。     

飞行目标落地姿态视觉测量方法研究

飞行目标落地姿态是评定飞行目标系统性能的重要技术指标.为了测量飞行目标落地姿态,采用放置在落弹点区域附近的凝视等待式双目视觉摄像机,高速摄影交汇测量飞行目标的落地姿态.根据目标在摄像机像面成像特点,将目标进行分类,并采用了不同的姿态测量方案.模拟实验与理论分析表明:该姿态测量方法正确、可靠,大目标和过渡目标姿态角测量误差小于1°,为飞行目标的姿态测量提供了一条新的便捷可靠的途径.     

便携式车轮定位参数视觉检测系统研究

将双目视觉测量技术应用到汽车四轮定位中,采用两个摄像机的立体视觉方法,采集目标板图像并提取目标板上特征点,并根据几何模型计算特征点的空间位置,求得目标板的空闯位姿,通过分析车轮运动模型建立车轮参数模型,进而得到需要的角度;完成了亚像素级角点提取并正确匹配,标定了两个摄像机的内外参数与视觉系统参数,得到了目标板的空间位姿,通过实验的方法,验证了方案的可行性,分析了误差来源,同时初步搭建了WINCE嵌入式实验平台进行嵌入式算法研究.     

空间编码与外极线斜率约束相结合的立体精匹配方法

三维型面非接触测量在工业领域有着广泛的应用前景。双目视觉是一种有效获取三维轮廓信息的方法，其中立体匹配是关键的一个步骤。本文提出了结合空间二进制编码与外极线斜率约束来实现立体精匹配的方案。首先利用空间编码将被测物空间划分成众多的不同编码区域．然后结合外极线斜率约束在左右两幅图像中具有相同编码的区城内寻找匹配点。该方法能够实现亚像素级的立体精匹配，改善了交向摆放姿态双目立体视觉系统的匹配质量。     

非接触目标相对姿态测量方法研究

针对空间中非接触目标相对位置、姿态角测量问题,采用双目摄像机、电控角位移台和电控旋转台建立物体相对姿态测量系统。提出了一种利用双目视觉结合物体刚体运动学原理,利用Harris算子提取物体特征角点进行相对姿态角解算。将卫星模型作为实验对象,运动过程中进行了非接触目标相对姿态测量方法的验证试验,实验结果表明姿态角测量误差小于±0.56°,证明了算法的有效性。     

一种基于双目视觉的奥制齿轮刀具参数测量方法

将双目视觉技术应用于奥利康齿制螺旋锥齿轮铣刀盘刀具的参数测量,通过双目标定获得系统的内外参数,并对待测刀具图像进行双目极线校正;提取待测刀具图像边缘轮廓并采用最小二乘法对直线边缘进行拟合,将共面直线交点作为匹配特征点,依据理想平行双目视觉系统三维重建方法求出刀具特征点的三维空间点坐标;利用空间点和空间平面的位置关系求取奥制齿轮刀具参数,通过实验对算法进行验证,实验结果证明了该测量方法的有效性,并具有一定的实际应用价值。     

砂轮地貌双目图像特征点提取和匹配研究

特征提取和匹配是双目视觉中的关键点和难点。对SIFT和Harris两种特征点提取算法应用于双目砂轮地貌图像的角点检测进行了研究,通过对SIFT特征采用欧式距离进行匹配,对Harris角点采用零均值归一化互相关算法(ZNCC)进行模板匹配,采用RANSAC算法剔除误匹配特征点对。实验结果表明,SIFT算法在双目砂轮地貌图像上应用较Harris算法效果理想。     

基于双目视觉的引磁片定位与测量研究

为了提高大批量生产中超薄磁性车载手机支架铁片的测量精度,提出采用双目视觉技术对引磁片定位,并基于鞍点法建立坐标系实现引磁片的高精度测量。首先通过HALCON的系统标定实现引磁片图像对的立体校正;利用金字塔算法与带有缩放的亚像素形状模板匹配实现引磁片特征点的提取。然后基于归一化互相关NCC(Normalized Cross-Correlation)的灰度匹配算法快速完成特征点的立体匹配;结合双目测距原理、坐标仿射转换对特征点重构获取以左相机为参考系下的3D坐标。最后通过空间曲线拟合公式和点积运算实现引磁片的高精度测量。实验结果表明,测量半径的误差小于0.1 mm、误差率小于1%;测量厚度误差小于0.1 mm、误差率小于6%,可有效的对超薄引磁片进行定位及尺寸测量。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.