结合聚类参数的圆投影模板匹配改进算法

针对圆投影模板匹配方法特征提取过程中损失大量图像信息的缺点,提出了结合聚类模型参数的线性光照鲁棒圆投影模板匹配方法。所提方法采用线性对比度拉伸来消除光照影响,并将模板图像各圆环内像素点的高斯混合模型聚类参数作为模板特征。匹配时通过一次迭代计算即可得到匹配误差,且该匹配过程可通过查找表来提高匹配速度。在目标搜索时使用了降采样搜索方法,并将降采样搜索匹配后各位置的误差均值作为自适应阈值,对匹配误差小于该阈值的降采样点邻域进行逐点匹配,匹配误差最小的位置作为最终匹配结果。试验及分析说明所提方法的定位误差及可靠度与基于归一化相关及均值的圆投影匹配算法相比有较大提高。     

Marr-Hildreth边界检测器定位性能分析

本文分析了Marr-Hildreth边界检测器(-△2G)在检测图象中的阶跃(step)边界时产 生定位误差的三个原因,即由于侧向曲率、高斯滤波和噪声干扰带来的影响.首先导出了拉普 拉斯、二阶梯度方向导数和侧向曲率三者之间的关系式,指出由于侧向曲率的影响,拉普拉斯 在检测弯曲边界时必然产生定位误差.依据按曲率分段逼近阶跃边界的模型,给出了误差的 定量分析.最后解释了高斯滤波和噪声干扰对定位的影响.     

点到隐式曲面的正交投影计算

针对点到隐式曲面的正交投影问题,提出一种稳定的几何迭代算法.首先构造初始点处的一条特殊的法截线,并给出沿着该法截线追踪投影点的二阶泰勒迭代方法;然后将给定点向初始点处的法截线的曲率圆作投影,提出基于曲率的步长控制策略,在此基础上给出了基于梯度的迭代误差矫正方法.仿真结果表明,该算法具有良好的收敛性、鲁棒性以及精确性.     

GPS定位与地图匹配方法研究

由于标准定位服务(SPS)的固有误差和市区环境的共同影响,使得GPS的导航精度难于满足车辆导航的需求.另外,从GPS获得的是参心大地坐标系的大地纬度和大地经度,而在大多数实际应用中,采用的国家坐标系或城市地方坐标系都不相同,因此有必要进行坐标变换.本文介绍了GPS定位原理、GPS所使用的WGS-84坐标系、我国常用的坐标系、高斯投影,采用最短距离法进行地图匹配,通过实验证明该算法能够实现GPS定位与道路实时、可靠的匹配.     

基于极坐标的改进灰度积分投影法的人眼检测

为了克服传统灰度积分投影方法无法有效定位旋转人脸图像中人眼的缺点,提出了一种基于极坐标系的灰度积分投影方法。利用肤色特征对给定图像进行人脸区域的确定,在人脸区域内按极角方向进行灰度积分投影,确定出人眼所在角度,将人眼角度方向的像素灰度值做水平方向积分投影,从而确定出人眼的位置。该方法能够实现同一幅图像中多个不同姿态人脸的人眼定位。大量的仿真实验表明,该方法的识别性能对人脸的旋转变化具有良好的鲁棒性,能够提高灰度积分投影方法对人眼定位的适用范围。     

基于曲率的点云数据配准算法

为了实现不同视角下测得的数据的多视定位,提出一种点云数据配准算法。该算法针对近邻内的点,采用二次曲面逼近的方法来求得每个点的曲率,并根据曲率的Hausdorff距离来寻找有效点集,建立名义上的对应关系,最后用四元组法来求得坐标变换,把数据统一到一个坐标系下。该算法利用曲率的性质准确判断对应点集,解决了任意多视点云的拼合问题,试验结果验证了其有效性和精度。     

基于图形变换的人体经络可视化

提出了一种可以检测并直观表示人体经络分布的实时定位和显示方法。首先,利用多通道经络阻抗检测仪和磁定位跟踪仪确定人体体表经络点的位置,获取经络点的三维信息;其次,对场景摄像机进行标定,并将其结果和经络点的三维信息通过图形变换技术变换到统一的世界坐标系下,获取摄像机的投影矩阵H;最后,根据该投影矩阵H,将经络点三维信息投影到二维图像上,形成二维经络线,并将其融合于场景摄像机拍摄的人体体表实时图像上,实现人体经络的可视化。测试结果表明,该方法能够准确有效地定位和显示人体经络。     

带非线性约束的自适应高斯和卡尔曼滤波目标跟踪算法

无线传感网络中运动目标状态通常满足某种非线性状态约束,为了提高对传感网络中运动目标的跟踪精度,降低非高斯噪声对状态估计的影响,避免高斯项数在迭代过程中的冗余累积,提出一种带非线性约束的权值自适应高斯和卡尔曼滤波算法.算法在每个时刻计算目标当前状态的高斯子项集合,并对每个高斯子项分别以无迹卡尔曼滤波进行状态估计.设计了一种高斯子项权值自适应策略动态调节子项权值,以实现无约束状态下的全局估计.将目标的非线性状态约束引入滤波器结构中时,考虑将其看作一类无约束状态估计的约束投影问题,通过状态约束信息先验来修正运动目标的状态估计.仿真结果表明,该算法与目前的非线性约束卡尔曼滤波相比具有更高的跟踪精度.     

WSN中利用改进FOA-GRNN和迭代Cubature卡尔曼滤波的实时目标跟踪方法

针对传统无线传感器网络(Wireless Sensor Network,WSN)对运动目标的定位和跟踪容易产生明显误差的问题,提出利用改进FOA-GRNN和迭代Cubature卡尔曼滤波的实时目标跟踪方法.基于改进FOA-GRNN法,利用从锚点接收到的运动目标的模拟(RSSI)值和相应的实际目标二维位置对GRNN进行训练,从而获得单个目标在二维运动时的准确初始位置;利用迭代Cubature卡尔曼滤波法对实时目标进行精准定位和测距,获得实时目标的准确定位和跟踪信息;将改进的FOA-GRNN法和迭代Cubature卡尔曼滤波法相结合用于WSN中实时目标跟踪和定位,在提高初始位置精度的同时,还提高了实时目标定位和跟踪信息的准确度.实验结果表明,相比其他几种较新的方法,该方法改善了WSN中实时目标的跟踪性能,降低了误差,提高了跟踪精度.     

基于法矢控制的B样条曲面逼近的PIA方法

提出了一种基于法矢控制的 B 样条曲面逼近的渐进迭代逼近(PIA)算法。一方面该方法将离散数据点的切失、曲率、法矢等几何特征充分应用到离散数据点的逼近问题上,利用数据点两个方向的切矢构造出数据点的法矢约束来控制逼近曲面形状,相比于无法矢控制的 B 样条曲面逼近的渐进迭代逼近(PIA)方法,逼近曲面更光顺,可获得更好的逼近效果。另一方面由于该算法选取主特征点作为控制顶点,所以允许在曲面拟合中控制顶点的数目小于数据点的数目。而且PIA算法的每次迭代过程中的各个步骤都是独立的,很容易被应用到并行计算上,可提高计算效率。本文还给出了一些实例来验证该算法的有效性。     

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.