基于辅助信息的无人机图像批处理三维重建方法

随着我国低空空域对民用的开放,无人机 (Unmanned aerial vehicles, UAVs)的应用将是一个巨大的潜在市场. 目前,如何对轻便的无人机获取的图像进行全自动处理,是一项急需解决的瓶颈技术. 本文将探索如何将近年来在视频、图像领域获得巨大成功的三维重建技术应用到无人机图像处理领域, 对无人机图像进行全自动的大场景三维重建.本文首先给出了经典增量式三维重建方法Bundler在无人机图像处理中存在的问题, 然后通过分析无人机图像的辅助信息的特点,提出了一种基于批处理重建(Batch reconstruction)框架下的鲁棒无人机图像三维重建方法.多组无人机图像三维重建实验表明: 本文提出的方法在算法鲁棒性、三维重建效率与精度等方面都具有很好的结果.     

深度学习背景下的图像三维重建技术进展综述

三维重建是指从单幅或多幅二维图像中重建出物体的三维模型并对三维模型进行纹理映射的过程。三维重建可获取从任意视角观测并具有色彩纹理的三维模型,是计算机视觉领域的一个重要研究方向。传统的三维重建方法通常需要输入大量图像,并进行相机参数估计、密集点云重建、表面重建和纹理映射等多个步骤。近年来,深度学习背景下的图像三维重建受到了广泛关注,并表现出了优越的性能和发展前景。本文对深度学习背景下的图像三维重建的技术方法、评测方法和数据集进行全面综述。首先对三维重建进行分类,根据三维模型的表示形式可将图像三维重建方法分类为基于体素的三维重建、基于点云的三维重建和基于网格的三维重建;根据输入图像的类型可将图像三维重建分类为单幅图像三维重建和多幅图像三维重建。随后介绍了不同类别的三维重建方法,从三维重建方法的输入、三维模型表示形式、模型纹理颜色、重建网络的基准值类型和特点等方面进行总结,归纳了深度学习背景下的图像三维重建方法的常用数据集和实验对比,最后总结了当前图像三维重建领域的待解决问题以及未来的研究方向。     

基于VTK的医学图像三维重建研究与实现

医学图像三维重建在放疗规划、解剖教学、医学诊断等方面具有重要的作用。本文首先介绍了可视化工具包VTK,然后对三维重建算法进行了概述,并重点研究了面绘制方法中的移动立方体算法和体绘制方法中的光线投射算法,最后,在VC++6.0环境下,采用可视化工具包VTK分别实现了移动立方体算法和光线投射算法,取得的良好的三维重建效果,并将其应用到了计算机辅助医学诊断软件中。     

医学图像三维重建系统设计与应用

随着现代计算机辅助技术、虚拟现实等现代技术的发展,人们对直观的三维医学图像的需求也日益增强,医学图像三维可视化近来成为医学成像发展的热点。本文以MATLAB为基础,设计并实现了一种便携式医学图像三维重建系统,其利用MATLAB软件的图像处理工具箱、GUI开发工具箱等,深入的集成了现代三维重建相关技术。并以具体的操作和医学实例介绍了MATLAB在医学图像三维重建中的应用。     

基于多景深融合模型的显微三维重建方法

鉴于激光共聚焦三维重建技术在金属样本的显微三维重建过程中具有重建速度慢的不足,在保证重建精度的前提下,提出一种基于多景深融合模型的显微三维重建方法来提升重建效率.该方法将三维重建问题转化为二维图像景深融合问题,首先提出一种基于非降采样Contourlet变换与多态脉冲耦合神经网络的图像融合方法,对不同景深图像序列运用该方法进行融合操作,得到的初代融合图像最大程度保留了原始图像信息;然后提出一种基于相关系数的区域图像匹配方法,得到以原始图像为基础的二次融合图像和初代高度映射图;最后定义一个能量泛函模型以消除二次融合图像中存在的假点信息,其极小化过程保证二次融合图像收敛于初代融合图像,同时初代高度映射图按照相同的方式演化,迭代结束即完成三维重建.运用文中方法对微尺度金属样本进行三维重建实验的结果表明,相比于激光共聚焦三维重建,该方法在保证三维重建结果具有较高精度与较好抗噪性的基础上,提升了重建效率.     

基于仿射CPD的股骨医学图像配准方法*

股骨医学图像配准是股骨三维重建技术的主要研究内容,通过机器辅助获得配准的参数决定了三维重建的准确性。针对传统ICP算法普遍存在的准确度和鲁棒性的较低问题,提出一种基于仿射CPD的股骨医学图像配准方法,使配准自动化以及精准化。该方法通过边缘提取获得浮动、参考点集;在配准后获取结果参数;通过结果参数将股骨通用模型摆成股骨个体化骨折姿态。实验结果：平移、旋转的平均误差分别小于2.1mm、 1.6;配准失败率仅在10%左右;三维重建后的3D图像真实度较高。结论：本文所述的方法对于图像配准和三维重建是可行的和高效的。     

基于图像运动的三维重建及虚拟化应用

提出了一种稳定、快速地获取摄像机视频运动图像的三维重建方法,并对该运动图像做适当的虚拟化处理以展示重建效果。采用基于尺度不变特征点匹配的摄像机标定进行三维重建。尺度不变特征对于视频图像中的特征具有优秀敏锐的匹配能力,极大地放宽了摄像机标定对于设备上的限制,拓宽了实时三维重建的适用范围。通过对系统的一系列优化,不但提升了三维重建的精度,减少了错误匹配对摄像机标定的影响,而且进一步提升了处理速度。通过在三维重建的基础之上进行虚拟化处理,展示了本系统的三维重建效果。实验结果表明,该系统适用范围广,处理速度较快,重建精度高,实现了基于视频运动图像的三维重建。     

采用密集多尺度卷积网络的胰腺分割方法

胰腺是人体内重要的消化器官,受个体年龄、健康状况等因素的影响,它的形状、尺寸和位置可能会发生较大变化.胰腺自动分割一直以来是医学图像分析和计算机辅助诊断领域一个具有挑战性的问题.近年来,深度学习在医学图像分割领域上得到了广泛的应用,本文提出了一种密集多尺度卷积网络(Dense multi-scale convolutional networks, DMC-net)以用于进行胰腺的自动分割.本文将多层图像作为网络输入,采用密集卷积和密集多尺度卷积连接代替了U-net的常规卷积和长跳跃连接,此外在训练过程中本文还采用了边界损失函数对胰腺的形状进行约束.在NIH胰腺公开数据集上的结果表明,文中方法的分割结果Dice系数可以达到86.19%,证明了本文提出的胰腺分割方法的有效性.     

基于SIFT特征匹配算子的三维重建方法研究

为了改善基于双目立体视觉的逆向工程中零件三维重建的精度,提出了一种基于尺度不变特征变换(SIFT)算子的三维重建方法.该方法通过SIFT算子搜索得到两幅对应的数字图像中的匹配特征点,并利用标定好的摄像机参数将图像特征点映射成空间直线,最后采用异面直线公垂线中点逼近法求取三维空间点的坐标.该方法不需要额外的设备来辅助特征点的匹配,实验结果表明该方法具有良好的鲁棒性.     

生物医学图像信息分析的相关研究

生物医学图像信息分析,是当今的前沿研究课题。文章介绍了在生物医学图像信息分析方面开展的相关研究及其方法,主要包括生物医学显微三维成像技术、心室压力-容积关系的超声图像分析与辅助诊断研究、基于光栅投影三维成像与三维重建的美容整容的设计技术。     

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。