基于近红外图像的人眼定位算法

为了能够快速准确地定位人眼,提出了一种基于近红外图像的人眼定位算法。使用主动红外光结构照明来产生亮瞳效应并产生候选区域,对于一些由于眼镜反射等因素没有亮瞳的图像,需要对其进行对称变换来产生候选区域;利用SVM算法对瞳孔区域进行分类确认;利用瞳孔的梯度以及几何特征快速准确定位到其中心位置。实验结果表明,该方法具有较高的可靠性和实时性。     

瞳孔和眼角的梯度特征重构快速定位算法

为了快速提取人脸图像局部特征点,提出一种基于梯度特征重构的瞳孔和眼角快速定位算法.通过分析人眼图像发现眼部区域的梯度特征以瞳孔为中心呈辐射状分布,根据梯度方向与辐射中心的关系提出了有限扩散的梯度能量函数;然后基于有限扩散的梯度能量函数进行瞳孔和眼角的检测与定位;之后,根据瞳孔和眼角几何约束关系进一步对定位结果进行合理化的调整,确保检测结果的稳定性.该算法只利用梯度信息,对光照线性变化不敏感.在Muct数据库和Bio ID数据库以及普通摄像头上进行了测试的结果表明,该算法检测精度高、计算复杂度低、检测速度快,可以满足实时应用.     

虹膜定位的快速算法

基于眼睛图像的几何特性,提出了一种基于最长弦的瞳孔定位算法,该算法能快速地检测到瞳孔的位置。由于图像中的瞳孔并不是规整的圆形,此方法与传统的基于圆灰度梯度检测算子的瞳孔定位算法相比能够更好地拟合瞳孔边界。在精确地定位瞳孔之后,根据瞳孔和虹膜近似同心的特性,利用圆灰度梯度检测算子在小范围内搜索虹膜的外边沿。与传统的虹膜定位方法相比,此算法避免了搜索的盲目性,提高了虹膜定位的速度和精度。     

基于形态学方法的虹膜快速定位算法

为提高虹膜的定位速度,提出一种粗定位与精定位相结合的虹膜快速定位算法。首先,利用阈值对人眼图像进行分割提取瞳孔,对二值化瞳孔区域进行形态学开运算去除瞳孔区域外睫毛等噪声点;然后选用一系列半径递增的结构元素对瞳孔区域进行形态学腐蚀操作,根据腐蚀结果粗略定位虹膜内边缘;最后利用圆梯度算子对虹膜内外边缘进行精确定位。对CASIA（version 1.0）虹膜数据库中100多幅虹膜图像进行定位实验,文中算法平均耗费时间为1.22秒,圆梯度算子耗时10.8秒,Hough变换方法耗时15.7秒。定位结果表明,文中算法对不同质量的虹膜图像定位速度快,精度高,鲁棒性强。     

基于灰度积分投影与霍夫圆变换算法的人眼瞳距自动检测

人眼瞳距在视光学研究中和配置眼镜时都是需要精确测量的基础性参数, 实现瞳距自动检测具有重要的应用价值, 结合高斯肤色模型, 提出一种基于灰度积分投影与霍夫圆变换算法的人眼瞳孔定位和瞳距计算方法. 首先, 通过二维伽马函数的自适应亮度校正方法对图像进行光照补偿预处理, 在此基础上, 利用肤色概率模型检测人脸并提取出面部区域. 再运用灰度积分投影法, 选取合适的阈值对眼部区域进行提取, 经过一系列形态学图像处理, 采用Canny边缘检测算子实现瞳孔边缘检测, 最后通过Hough圆变换算法进行瞳孔定位, 并对其中心距离进行计算. 研究结果表明, 该算法具有较快的瞳孔定位速度, 能够较精确地实现瞳距自动测量, 为瞳孔测距的智能化技术研究奠定了基础.     

基于SUSAN角点和HSV颜色模型的粒子滤波目标跟踪算法

针对传统粒子滤波目标跟踪算法在目标与背景颜色相似情况下目标定位偏差大、易导致丢失目标的缺陷,提出一种基于角点和颜色模型的粒子滤波目标跟踪算法。首先,提出一种改进SUSAN角点检测算法,采用圆形模板邻域内像素灰度值中值代替模板中心像素灰度值作为模板"核"来检测区域目标角点,其改进SUSAN角点算法在继承原有SUSAN算法计算简单、定位准确、具有旋转不变性等特点的同时,具有更好抗噪声性能;其次,利用HSV颜色模型光照不敏锐特性,对检测到的角点建立HSV颜色模型,并将其嵌入到粒子滤波框架中,实现对目标的跟踪。实验结果表明,当背景与目标颜色相近时,该算法能够有效避免背景对目标的干扰,取得了较好的目标跟踪性能。     

视线追踪系统中特征参数提取方法研究

为了提取人眼的高精度亚像素特征参数,利用亮瞳现象,提出了一种基于多通道图像的高精度亚像素特征参数提取方法。该方法首先通过差分图像滤波获得瞳孔区域,进而检测瞳孔区域的边缘,并在眼睛区域附近基于灰度,搜索角膜反射区域; 然后求取其质心用于定位角膜反射区域中心,并对瞳孔边缘做滤波,以消除角膜反射对瞳孔边缘轮廓的影响,进而利用椭圆拟合来定位瞳孔中心;最后提取包括人眼特征和人脸位置的多个参数,另外,还建立了一个多特征参数提取的流程,为下一步的视线估计提供了参数依据。 实验结果及视线追踪系统最终的视线估计结果证明,该方法是有效的。     

采用有向梯度与RANSAC的虹膜定位算法

针对虹膜图像中有较多光斑的情况,提出一种基于有向梯度和随机抽样一致性（RANSAC）相结合的虹膜定位算法。该算法根据瞳孔内某点利用有向梯度提取内缘像素点,采用RANSAC定位虹膜内缘;下采样虹膜图像,利用圆差分算子在瞳孔左右两侧拟合出两个圆,进而合并为一个圆;根据圆的参数在虹膜图像中快速精确定位外缘。实验结果表明：该算法在正确率、定位速度和鲁棒性方面均优于传统的虹膜定位算法。     

梯度估计在眼睛特征提取中的应用

眼睛特征的提取在表情分析、人脸合成和人脸识别等应用中起着非常重要的作用.目前广泛使用的眼睛特征提取算法是基于模板匹配的算法和基于特征点的算法.然而基于模板匹配的算法通常需要进行多个参数的选择,而且匹配过程非常耗时;特征点的算法则存在准确度较低的问题.针对以上问题提出了一种基于梯度信息提取虹膜中心、虹膜外轮廓和眼睛角点等眼睛特征的算法,算法用改进霍夫变换提取虹膜中心和外轮廓.在获得虹膜中心点后,参照中心位置选择眼睛角点候选区域并对其梯度进行分析.依据角点附近梯度分布与其它区域梯度分布不同的性质定位角点.仿真结果表明提出的算法能有效的提取眼睛特征,在测试数据上得到了比其它算法更高的准确率和更快的速度.     

基于YCbCr模型和形态学的瞳孔分割及人脸检测

该文提出了一种精确度高、抗干扰性强的人眼瞳孔分割方法,并利用这种方法定位人脸。先利用YCbCr模型提取人脸候选区域,然后根据人眼瞳孔的圆形特征,从形态学入手,先利用YCbCr模型提取人脸候选区域,然后根据人眼瞳孔的圆形特征．使用形态学方法增强瞳孔和其他区域的对比度,最后对瞳孔进行投影以确定瞳孔位置。当人脸候选区域和瞳孔区域的交集就是要找的人脸,最后对人脸进行归一化处理。该文提出的形态学方法同时保留了艟孔的圆形形状和灰度对比度,并利用这种方法定位人脸。     

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.