结合梯度投影稀疏重构和复数小波的图像重构

压缩感知主要包括随机投影和重构两部分。针对迭代收缩算法收敛速度较慢,普通二维小波变换缺少方向性表示的缺点,利用置乱离散余弦变换（PDCT）实现随机投影,重构时采用梯度投影算法,在简化计算的基础上,通过迭代的方式完善图像在双树复数小波域的变换系数,最后经反变换后得到重构图像。在同一重构算法下,比较了利用双树复数小波变换和双正交小波变换的重构结果,结果表明前者重构后的图像在细节和平滑度上优于后者,在峰值信噪比（PSNR）上平均高出约1.5 dB;同一稀疏域中,梯度投影算法的收敛速度优于迭代收缩算法;相同稀疏域和重构算法下,PDCT与结构随机矩阵相比在PSNR上略高。     

基于复数小波域的多聚焦图像融合

提出了一种基于Q-shift双树复数小波变换的图像融合方法,该方法利用Q-shift双树复数小波变换对图像进行分解,根据低、高频系数相关性的特点,采用邻域梯度取大和"合成图像模值取大"相结合的融合方法对低、高频系数分别进行融合,并对高频融合结果进行"一致性"校验。实验表明,本文算法具有优于基于小波变换方法的性能。由于Q-shift双树复数小波近似的平移不变性和良好的方向选择性,因此能够有效地避免空间域融合算法存在的对比度低、块效应等问题以及基于小波变换融合算法存在的"伪影"和"振铃效应"。     

一种基于双树复小波变换的图像融合方法

提出了一种基于双树复小波变换的图像融合方法。采用双树复小波变换对源图像进行分解后,该方法首先对各频域分别定义一种活性测度和匹配测度,再通过相应的匹配测度来计算各频域的融合因子,然后采用加权与选择相结合的规则融合高频系数和低频系数,得到融合图像的各频域系数。最后,采用双树复小波逆变换重构得到融合图像。实验表明,该融合方法具有良好的客观评价性能和主观视觉效果。     

基于复数小波域广义高斯分布模型的纹理图像检索

由于在频域用能量参数来表示图像的特征矢量缺乏准确性,而且实数离散小波变换具有平移变化性和弱的方向选择性,为此针对以上问题提出了一种基于复数小波域广义高斯分布模型的纹理图像检索方法。该方法首先利用双树复数小波变换系数的统计特性来建立广义高斯分布的统计模型;然后基于该模型提取图像的特征矢量;最后利用Kullback-Leibler distance(KLD)测度算法进行纹理图像检索。对Brodatz图像库的仿真表明,新方法较双树复数小波算法的查准率提高6.96%,较基于Gabor纹理特征检索法的查准率提高了18.8%。同时复数小波系数统计模型具有旋转不变性。新方法对今后的纹理图像检索具有重要的理论与实际意义。     

基于区域特性的压缩感知多聚焦融合算法

传统的基于压缩感知的图像融合算法是对整个系数进行稀疏处理,而小波分解后的低频系数不稀疏,导致压缩重构质量降低,并且传统的融合规则不易简单、全面地提取高频系数的特征值。针对这一问题,分别对小波分解得到的高、低频系数采取不同的融合规则进行处理,提出了一种改进的区域特性高频压缩感知的融合算法。其中,低频系数采用区域方差加权绝对值最大融合;高频系数首先通过具有较好RIP性质的随机观测矩阵进行压缩采样,得到的观测值基于能量匹配度的不同进行相加或加权融合,以融合不同方向的高频子带特征信息,再用正交匹配追踪重构算法对高频部分进行信号重构。最后,低频、高频信息在小波逆变换下重构出融合图像。实验结果表明,与以往的基于压缩感知的融合方法相比,此算法的融合图像更清晰,新算法无论是在主观评价还是客观评价指标上都有利于图像信号重构,并具有较好的使用性。     

基于复数小波域广义高斯分布模型的

由于在频域用能量参数来表示图像的特征矢量缺乏准确性,而且实数离散小波变换具有平移变化性和弱的方向选择性,为此针对以上问题提出了一种基于复数小波域广义高斯分布模型的纹理图像检索方法。该方法首先利用双树复数小波变换系数的统计特性来建立广义高斯分布的统计模型;然后基于该模型提取图像的特征矢量;最后利用KullbackLeibler distance(KLD)测度算法进行纹理图像检索。对Brodatz图像库的仿真表明,新方法较双树复数小波算法的查准率提高6.96%,较基于Gabor纹理特征检索法的查准率提高了18.8%。同时复数小波系数统计模型具有旋转不变性。新方法对今后的纹理图像检索具有重要的理论与实际意义。     

基于单层双树小波变换和平滑零范数法的压缩感知图像重构

基于压缩感知理论,从图像稀疏变换方式和压缩感知恢复算法两方面出发,对原有算法进行改进,提出了基于单层双树小波变换和平滑零范数法(Smoothed-L0)的压缩感知图像重构算法(DTSL0 )。该算法的思想是:对原始图像进行双树实系数小波稀疏变换,并使用Smoothed-L0压缩感知恢复算法予以重构。仿真实验表明:该算法在图像重构质量、执行速度,以及鲁棒性方面均有显著提升。     

基于压缩感知理论的图像融合方法

基于压缩感知（Compressed Sensing,CS）理论,提出了一种采样点少且结构简单易实现的图像融合方法。对需要处理的两幅或多幅图像进行小波变换,分别对得到的小波系数进行稀疏处理得到稀疏矩阵,通过系数绝对值较大法进行融合,对融合后的系数矩阵通过随机观测获取压缩采样,而图像恢复则是对得到的压缩采样通过求解最优化的问题得到。由于对小波系数进行了稀疏处理,故该方法可以用少量的采样点来恢复图像。实验结果表明,在相同采样点下,该方法得到的图像质量（PSNR）明显优于传统的系数绝对值较大法融合;在少量采样点下,采用该方法也可以使融合的图像达到较好的效果。     

一种改进小波变换的图像融合方法*

基于压缩感知理论,本研究针对于图像的小波分解系数的特点,提出了一种改进的小波稀疏表示的压缩感知图像融合算法。首先,本算法通过Mallat快速算法对图像进行稀疏分解;然后,利用绝对值最大融合规则对小波系数在压缩域进行融合;最后,使用最小全变分的方法重构融合图像。实验结果表明,该算法具有良好的融合效果。     

结合NSDTCT和压缩感知PCNN的图像融合算法

针对基于传统小波变换的图像融合算法存在的不足,提出一种基于非下采样双树复轮廓波变换(NSDTCT)和压缩感知脉冲耦合神经网络(CS-PCNN)的图像融合算法.首先将源图像经过NSDTCT分解后得到低频子带及高频子带系数;对于低频子带系数,提出了基于区域平均梯度、区域能量和S函数相结合的自适应加权融合规则;对于数据量较大的高频子带系数,提出了基于CS-PCNN理论的融合规则,并将改进的拉普拉斯能量和作为PCNN的外部输入;最后对融合系数进行NSDTCT逆变换,得到融合图像.实验结果表明,该算法可以有效地提高图像融合的计算效率和质量,在视觉效果及客观指标上均优于一些经典的融合算法.     

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。     

基于QTE的蒙古文显示机制研究与实现

蒙古语言是中国蒙古族使用的通用语言,由于蒙古文区别于其他文字的书写方式和其自身变形机制等特点,在很多通用的文字处理引擎中都不被支持。在嵌入式产品开发与应用领域中Linux加QTE已经成为流行方式。该文给出了一种在QTE环境上实现基于标准Unicode的蒙古文点阵显示和变形算法, 并自定义了支持蒙古文的QTE组件,扩展了QTE功能,为在Linux加QTE方式的嵌入式体系结构中处理蒙古文提供了一种解决方法。