一种用于视频超分辨率重建的块匹配图像配准方法

图像配准是超分辨率重建中的一个关键问题, 直接影响超分辨率重建图像的质量. 本文在自适应十字搜索(Adaptive rood pattern search, ARPS)块匹配算法的基础上, 根据小波域中各图像之间的相关性, 提出一种分层块匹配算法---基于小波变换的改进的自适应十字模式搜索算法(Improved adaptive rood pattern search algorithm based on wavelet transform, W-IARPS), 该方法在小波变换域完成匹配宏块的搜索, 有效地减少了匹配点的搜索个数, 且配准图像的峰值信噪比相比全搜索算法下降不到0.l dB, 保持了较高的配准精度. 最后采用凸集投影(Projections onto convex sets, POCS)算法对配准后的图像进行超分辨率重建, 取得了较好的视觉效果. 实验结果表明, 该方法具有较高的配准精度和重建效果, 算法稳健可靠.     

一种多幅欠采样图像的凸集投影超分辨率重建方法

介绍了一种由多幅欠采样低分辨率图像重建一幅高分辨率图像的凸集投影超分辨率重建技术。首先介绍了超分辨率空间域迭代重建方法中一个至关重要的因素--成像过程模型;其次通过介绍凸集投影的理论依据,给出了插值-模拟采样迭代超分辨率重建方法的模型和重建步骤;最后通过实验数据对算法进行了验证。     

压缩视频的正则化投影超分辨率重建

压缩视频超分辨率（SR）技术利用压缩后的低分辨率（LR）图像序列来重建高分辨率（HR）图像的技术,是当前视频超分辨率技术研究的热点。在正则化理论和凸集投影理论的基础上,利用比特流中的量化信息,提出了一种正则化投影超分辨率重建算法;通过正则化代价函数引入图像序列的时间域和空间域的先验信息,使用迭代梯度下降算法对正则化代价函数求解得到重建图像,最后利用凸集投影算法对求得的估计图像进行DCT域投影重建。仿真实验结果表明,该自适应算法较传统算法,其重建图像的主、客观质量有一定的提高,适合压缩图像的应用。     

基于小波的POCS超分辨率图像重建

本文在分析现有SR重建方法的基础上,提出了基于小波的POCS超分辨率图像重建算法。此算法是传统POCS算法的扩展,在小波域执行一些凸投影操作,并利用随机小波系数优化技术来修正高分辨率图像估计的小波子图像系数。     

基于小波域HMT模型的序列图像超分辨率重建*

鉴于基于小波域隐马尔可夫树的噪声抑制性和较好的边缘保持性,提出一种基于小波域隐马尔可夫树的序列图像的超分辨率重建算法。针对小波系数进行统计建模,讨论了不同尺度小波系数之间的隐马尔可夫树结构,利用了序列图像的运动信息,运用极大后验概率估计和贝叶斯原理,将小波域HMT作为图像先验知识并给出了超分辨率重建算法,最终通过EM算法和共轭梯度算法的交替迭代进行优化计算。实验结果表明方法的重建效果得到了明显的改进。     

基于压缩感知的声纳图像超分辨率重建算法

超分辨率重建通用方法中,图像分解后对应小波基只能有效稀疏表示单一成分,往往只侧重边缘成分而忽略了光滑成分等。针对这个问题,本文改进了一种基于压缩感知的声纳图像超分辨率重建算法。该算法基于三种不同稀疏字典小波变换模型,运用一种基于K-均值聚类算法的结构化字典训练法,并采用Newton-Raphson法进行迭代算法处理,实现声纳图像压缩感知的超分辨率重建。最后通过仿真实验,验证了此种算法的可行性和有效性。实验结果表明,该算法获得的超分辨率图像能够很好地重建并保持原图像的特征,能高效地改善并提高重建质量。     

空间移不变系统图像超分辨复原的快速解耦算法

超分辨率图像复原是当今一个重要的热门研究课题. 本文提出了一种基于全变差模型的超分辨率复原快速解耦算法. 利用半二次正则化思想, 提出了一个新的解耦TV (Total variation)模型. 利用交替最小化方法和线性空间不变模糊的性质将上采样融合、去模糊和去噪分步进行. 算法中对上采样融合采用非迭代的直接计算方法; 去模糊过程采用基于变换的预处理共轭梯度迭代算法, 而去噪过程采用了子空间投影方法. 本文算法降低了算法复杂度; 超分辨率重建图像在去除噪声的同时, 不仅能够保证图像平坦区域的保真度, 较好地抑制阶梯效应的产生, 而且能够保持图像中边缘等重要几何结构的清晰度.     

基于小波域CHMT模型的超分辨率图像重建

从图像重建的Bayesian方法出发,提出一种基于小波域分类隐马尔可夫树(CHMT)模型的超分辨率图像重建算法.将CHMT模型作为自然图像小波域的先验知识,采用混合高斯模型刻画备子带系数的概率分布,将起分辨率图像重建问题转化为一个约束最优化问题,并采用共轭梯度算法进行求解.同时,提出了自适应的规整化参数选择方法.实验结果表明,该算法具有较低的计算复杂度,在峰值信噪比和视觉效果方面都有所提高.     

基于Curvelet变换的压缩传感超分辨率重建

为了在无训练集的情况下,改善单帧退化图像的分辨率,实现了一种基于Curvelet变换和快速迭代收缩阈值法(FIST)的压缩传感超分辨率重建算法(Curvelet-FIST)。算法首先对低分辨率图像建立伪星形采样的采样方式,利用压缩传感理论,在Curvelet变换域,通过快速迭代收缩阈值法由采样值恢复出高分辨率图像。仿真实验表明,此超分辨率重建算法比传统的插值算法以及基于Wavelet变换和FIST的压缩传感重建算法(Wavelet-FIST)有更高的峰值信噪比。     

可实现图像自修复的压缩感知超分辨率成像

为了在不增加系统复杂度的前提下实现对降质图像的传输、修复及超分辨率成像,基于压缩感知理论和图像的退化模型建立了一个新型的压缩感知系统.该系统利用图像退化模型中降采样操作和模糊算子改进测量矩阵,并提出了基于小波-Shearlet的图像变换作为稀疏表示方法,在重构端结合迭代硬阈值算法重建图像.实验结果表明,文中系统在重构图像的质量和运算效率上均具备一定优势.     

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.