基于快速DCT的画面内块的空域内插

主要介绍对边界像素进行约束来恢复画面中块的方法.这种方法基本假设前提是如果对块中丢失和它的边界像素进行DCT变换,含高频成分系数归化为零,这样就可以得到一系列线性方程,通过对这些方程求解就可以求出丢失的像素的近似值.这种方法只需对八个边界像素进行运算.     

NMI特征优化边界敏感的LSC遥感影像分割算法

针对线性谱聚类方法处理复杂场景的高分辨率遥感影像时存在地物边界丢失、过分割问题,提出基于归一化转动惯量特征优化边界敏感的线性谱聚类方法。首先,利用LOG算法提取影像边缘信息,将边缘信息与LSC算法融合,并将存在边缘信息的超像素块的区域质心替代原始聚类中心,改善地物边界信息丢失问题;然后,通过边缘敏感的LSC分割方法,对高分辨率影像进行分割,获取地物完整的初始超像素,并确定微小的超像素;最后,计算微小超像素与相邻超像素相似性度量值,并将其合并到相似性度量值最小的超像素,优化过分割结果。实验结果表明,该方法可以有效地解决地物边界丢失、过分割问题,获取较好的分割结果。     

基于边缘检测及方向加权的H.264帧内错误隐藏算法*

针对H.264帧内错误隐藏忽略边缘纹理信息的问题,提出了一种改进算法。首先对丢失块的相邻块的像素作边缘检测,统计相关像素的个数,确定相邻块的边缘方向;然后通过距离和相关像素进行加权,以估计出丢失块每个像素的插值方向;最后,通过对宏块状态标志进行检测,选择插值方法,完成插值运算。在H.264标准测试平台JM86上对该算法进行验证,结果表明：在像素丢失块达50%的恶劣情况下,该算法的PSNR值比空间像素加权算法提高了211 dB。     

基于模糊识别的块编码图像帧内误码掩盖技术

采用基于模糊识别的误码掩盖方法来对块编码的灰度图像进行帧内的误码掩盖。首先对丢失块进行周围像素匹配,找到最佳匹配块,然后采用模糊识别技术来对最佳匹配块的恢复效果进行模糊分类,并根据分类的结果对恢复较差的块采取相应的修正处理:对于平滑纹理进行改进的像素逐点修正,而对于复杂纹理则采用分块再匹配方法,从而达到有针对性地掩盖误码、改善视觉效果的目的。实验结果表明,对于具有复杂纹理和精细细节的图像,采用本文方法可以获得比较满意的结果,不仅在主观上可以获得较好的恢复效果,而且PSNR也有较大的提高。     

自适应时域差错掩盖方法

差错掩盖作为视频传输中的重要技术之一,可以有效地弥补视频在传输过程中,因为传输环境等原因造成的数据丢失及数据错误,最大程度地保证视频在到达接收端后可以保持令人满意的质量。通过提出一种可应用于基于块编码系统的自适应时域差错掩盖方法,同时估计丢失宏块的运动及丢失宏块中的像素运动,并根据每个像素的不同情况,自适应地将两个估计的运动结合,获得最终的像素恢复值。实验结果表明,该方法相比原有方法,在主观和客观质量上都有较大的提高。     

城市航空影像中建筑群的FCM聚类分割方法

在低分辨率城市航空影像中建筑群由于阴影的存在造成其灰度呈现明暗变化，采用基于像素级的分割方法以及阈值分割方法均不能得到好的结果。为了充分利用这种明暗变化的信息，讨论了一种以图像子块灰度的标准差和直方图的墒作为特征矢量，采用基于模糊C-均值(FCM)的分块聚类方法用于建筑群的粗略分割，由于分块有重叠，造成边界块的归属不明确，因此根据包含边界块的子块的隶属度来确定边界块的归属，从而得到了正确的边界区域，并利用区域生长和闭合运算对边界进行细化。对实际图像进行实验结果表明，该方法是有效的。     

基于分块方向梯度能量的图像修补算法

为了对图像破损区域进行修补和前景去除,提出一种基于样本的图像修补算法.首先引入“分块的方向梯度能量”来评估像素块在某个方向上的整体颜色变化情况;然后利用最大方向梯度能量估算该像素块中存在的边缘的强度与方向.该算法包括像素块填充优先级计算、像素块匹配和更新未知区域边界、可信任度等全局参数的更新3个步骤.在计算像素块填充优先级时,考察像素块在待修补区域边界法向上的方向梯度能量,优先选取包含更强边缘信息的未知区域;而在像素块匹配过程中,除比较像素块对应的颜色值之外,还利用方向梯度能量对它们可能存在的边缘进行比较与匹配.实验结果表明,该算法能够使图像的结构信息正确地传播到待修补的未知区域中,填充后的图像具有较为平滑的边缘.     

时空域相结合的视频差错掩盖方法

为了克服视频解码端时域差错掩盖技术不能准确估计丢失块运动矢量的缺点,提出了一种将解码端运动估计和隐藏运动模型相结合的误码差错掩盖方法。首先,利用丢失块 周围正确接收像素估计丢失块运动矢量,并计算估计的准确性。然后根据准确性,通过隐藏运动模型充分利用丢失块的空域和时域相关性进行差错块的掩盖。仿真结果表明,与现 有的算法相比,该方法能有效提高重建视频图像质量平均近1dB。     

利用改进的图像修复的联合帧间差错隐藏算法

针对图像修补的不足和视频帧间编码的特点,提出利用改进的图像修复的帧间差错隐藏联合算法.根据丢失宏块的周围宏块的运动相关性和正确接收情况对丢失宏块进行运动性和可用性判断,如果丢失宏块属于静止宏块且可用性不为零,则采用改进的图像修补隐藏帧间差错,否则采用外边界匹配准则进行差错隐藏;并在图像修补中对置信度、等照度和修复方向等方面进行了改进.该算法既发挥了图像修复对纹理丰富区域的修复优势,也克服了图像修补对运动区域的隐藏效果不好的缺陷.实验结果表明,该算法可以带来主观和客观质量上的提高,并且明显克服了外边界匹配算法带来的视频抖动.     

基于深度学习的虚拟边界检测方法

针对传统边缘检测方法无法对材料微观图像中不同区域间存在的"虚拟边界"（VB）进行准确检测的问题,提出一种基于卷积神经网络（CNN）的虚拟边界检测模型,称之为"虚拟边界网络"（VBN）。该模型对VGGNet深度学习模型进行了简化,并在模型训练过程中采用了dropout以及Adam算法等优化策略。VBN以图像中每个像素为中心所取的图像块作为输入,然后输出该图像块所属的类别并据此判断中心像素是否属于虚拟边界。在对两类材料图像进行虚拟边界检测的实验中,VBN的平均检测精度到达92.5%,平均召回率达到89.5%,证明该模型能够准确、有效地对图像中的虚拟边界进行检测,是一种替代低效率人工分析方法的有效手段。     

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.