检索结果-内蒙古大学图书馆

A combined integral transform asymptotic expansion method for the characterization of interface flaws through pulsed infrared thermography1

引用

Quantitative InfraRed Thermography Journal 2007年第1期4卷 3-23页

作者： Bendada, Abdelhakim Ibarra-Castanedo, Clemente Maldague, Xavier Computer Vision and Systems Laboratory Department of Electrical and Computer Engineering Université Laval Quebec City G1K7P4 Canada

This work is devoted to the non-destructive evaluation of materials using stimulated infrared thermography. The proposed approach provides simple analytical solutions to evaluate the lateral extent, and the thickness of a plane flaw in a three-dimensional (3D) heat transfer configuration. It is based on the application of a Laplace transform on the time variable t, then a double Fourier transform on the space variables x and y. Reduction of the models is obtained through an asymptotic expansion method. This mathematical formalism leads to the construction of explicit relationships that are very convenient for quantitative inversion. An experimental validation of the inversion procedures is performed on calibrated carbon-epoxy laminates. A particular attention is dedicated in the second part of this work to the experimental analysis of the impact of the definition of the experimental thermal contrast and the sane (i.e., non-defective) area on the inverted parameters. The analysis is carried out through a comparison between two classical definitions of the thermal contrast and a new method, the DAC contrast, developed recently by our team. The impact of a hyper parameter of the inversion procedures (i.e., the Laplace variable) is also analyzed. Both analyses are illustrated through an experiment aiming to estimate the depths of some calibrated flaws in a CFRP laminate. © 2007 Taylor & Francis Group, LLC. All rights reserved.

关键词： 3D heat transfer DAC thermal contrast Flaw characterization Infrared thermography Mathematical perturbations Non destructive evaluation Thermal quadrupoles

来源：评论

学校读者我要写书评

暂无评论

vision-based target geo-location using feature tracking

Vision-based target geo-location using feature tracking

引用

AIAA Guidance, Navigation, and Control Conference 2007

作者： Pachter, Meir Ceccarelli, N. Chandler, P.R. Department of Electrical and Computer Engineering Air Force Institute of Technology Air Force Research Laboratory Wright-Patterson Air Force Base OH 45433 United States Dept. of Electrical and Computer Engineering NRC Air Force Research Laboratory AFRL/VACA United States

ISBN: (纸本)1563479044

A method for determining the location of a fixed ground target when imaged from the air using a camera equipped Micro Air Vehicle (MAV) is developed. The ground objects' elevation is assumed known. Rather than a "one shot" affair, multiple bearing measurements of the ground object taken as the aircraft flies around the target are used. This makes it possible for the adverse effects of both the random measurement errors and the systematic measurement errors, a.k.a., attitude sensor biases, to be mitigated. The main result of this paper is that when bearing measurements of a target are taken over time, the target's position and the MAVs systematic attitude measurement errors can be jointly estimated using linear regression. As a result, the target is accurately geo-located and the attitude sensors are calibrated. If only one target bearing measurement can be taken, the attitude sensors will be calibrated prior to arrival at the target area using an Initial Point (IP). The technique has been successfully tested on actual flight data.

关键词： Target tracking

来源：评论

学校读者我要写书评

暂无评论

Measuring Land Development in Urban Regions using Graph Theoretical Features

Measuring Land Development in Urban Regions using Graph Theo...

引用

International Conference on Recent Advances in Space Technologies (RAST)

作者： Cemr Unsalan Computer Vision Research Laboratory Department of Electrical and Electronics Engineering Yeditepe University Istanbul Turkey

Inferring land use from satellite images is studied extensively. In previous studies, the focus was on classifying large regions due to the resolution of available satellite images. Nowadays, very high resolution satellite imagery (Ikonos and Quickbird) allow researchers to focus on more complex land use problems such as monitoring development in urban regions. Solutions to these complex problems may improve life standards of city residents. To this end, we focus on automatically monitoring construction zones using their very high resolution panchromatic satellite images through time. To monitor land development, we obtain sequential images of a selected region. Then, we extract features from each image in the sequence. Comparing values of these features, we expect to measure the degree of land development through time. Here, we introduce four new graph theoretical features to the existing ones. We test all our existing and new features to measure land development in 19 different urban construction zones. Our test set consists of Ikonos satellite images of these regions imaged in separate times.

关键词： Satellites Image resolution Gray-scale Time measurement Spatial resolution Monitoring Cities and towns Testing Electric variables measurement computer vision

来源：评论

学校读者我要写书评

暂无评论

Detecting Changes in Multispectral Satellite Images using Time Dependent Angle Vegetation Indices

Detecting Changes in Multispectral Satellite Images using Ti...

引用

International Conference on Recent Advances in Space Technologies (RAST)

作者： Cemr Unsalan Computer Vision Research Laboratory Department of Electrical and Electronics Engineering Yeditepe University Istanbul Turkey

Change detection using satellite images is of major concern to government agencies, military, and scientists. Government agencies can monitor the construction activity on a region automatically by detecting changes. They can update maps accordingly. Forests in satellite images may be monitored automatically for any change in their condition. As for military applications, strategic plans may be updated based on the observed changes on targets. After a natural disaster, even if that region can not be reached, automatically detecting changes in the region's satellite image may provide necessary information to measure the effect of the damage. To solve all these and related problems, there exists commercially available high resolution satellite images. The problem here is automatically detecting changes using these images. In this study, we introduce a method using multispectral information to detect changes on Ikonos imagery.

关键词： Vegetation mapping Military satellites Principal component analysis Image resolution Government computerized monitoring Spatial resolution computer vision Condition monitoring Remote sensing

来源：评论

学校读者我要写书评

暂无评论

Editorial: Knowledge engineering, semantics, and signal processing in audio - visual information retrieval

引用

IEEE Transactions on Circuits and Systems for Video Technology 2007年第3期17卷 257-258页

作者： Izquierdo, Ebroul Zhang, Jian Sikora, Thomas Huang, Thomas S. Department of Electrical Engineering Queen Mary University of London London El 4NS United Kingdom Sydney Australia School of Computer Science and Engineering University of New South Wales Australia Communication Systems Group Technical University Berlin Berlin Germany ITG University of Illinois at Urbana-Champaign United States Department of Electrical and Computer Engineering Coordinated Science Laboratory United States Image Formation and Processing Group Beckman Institute for Advanced Science and Technology United States Institute's Major Research Theme Human Computer Intelligent Interaction National Academy of Engineering Chinese Academies of Engineering and Sciences China International Association of Pattern Recognition Optical Society of American United States

No abstract available

关键词： Special issues and sections Knowledge engineering Information retrieval Audio-visual systems

来源：评论

学校读者我要写书评

暂无评论

Spartacus attending the 2005 AAAI conference

Spartacus attending the 2005 AAAI conference

引用

作者： Michaud, F. Côté, C. Létourneau, D. Brosseau, Y. Valin, J.-M. Beaudry, E. Raïevsky, C. Ponchon, A. Moisan, P. Lepage, P. Morin, Y. Gagnon, F. Giguère, P. Roux, M.-A. Caron, S. Frenette, P. Kabanza, F. LABORIUS - Research Laboratory on Mobile Robotics and Intelligent Systems Department of Electrical Engineering and Computer Engineering Université de Sherbrooke Sherbrooke Qué. J1K 2R1 Canada CSIRO ICT Center Sydney Australia

Spartacus is our robot entry in the 2005 AAAI Mobile Robot Challenge, making a robot attend the National Conference on Artificial Intelligence. Designing robots that are capable of interacting with humans in real-life settings can be considered the ultimate challenge when it comes to intelligent autonomous systems. One key issue is the integration of multiple modalities (e.g., mobility, physical structure, navigation, vision, audition, dialogue, reasoning). Such integration increases the diversity and also the complexity of interactions the robot can generate. It also makes it difficult to monitor how such increased capabilities are used in unconstrained conditions, whether it is done while the robot is in operation of afterwards. This paper reports solutions and findings resulting from our hardware, software and decisional integration work on Spartacus. It also outlines perspectives in making intelligent and interaction capabilities evolve for autonomous robots. © Springer Science+Business Media, LLC 2007.

关键词： Robots

来源：评论

学校读者我要写书评

暂无评论

vision aided proportional navigation for micro air vehicles

Vision aided proportional navigation for micro air vehicles

引用

AIAA Guidance, Navigation, and Control Conference 2007

作者： Beard, Randal W. Will Curtis, J. Eilders, Martin Evers, Johnny Cloutier, James R. Brigham Young University Provo UT 84602 United States Air Force Research Laboratory Eglin AFB FL 32542-6810 United States Department of Electrical and Computer Engineering AIAA Munitions Directorate Guidance and Navigation Branch Control Systems Research

ISBN: (纸本)1563479044

Most of the applications envisioned for micro air vehicles require an on-board E(MR camera. It is only natural to investigate using the on-board camera as a sensor for navigation, guidance, and control. This paper investigates the use of an EO/IR sensor as a seeker in a proportional navigation guidance law for micro air vehicles. Proportional navigation strategies require knowledge of the line-of-site rates and range rate between the vehicle and the target. This paper demonstrates how these quantities can be derived from pixel-specific information provided by an EO/IR sensor. The guidance laws are developed for gimbaled and strapdown sensors on both skid-to-turn and bank-to-turn MAV kinematic models.

关键词： Navigation

来源：评论

学校读者我要写书评

暂无评论

computer vision Studies Using Stochastic Resonance/Information-theoretic Methods

Computer Vision Studies Using Stochastic Resonance/Informati...

引用

IEEE International Symposium on Computational Intelligence in Robotics and Automation (CIRA)

作者： D. W. Repperger R. G. Roberts A. R. Pinkus Air Force Research Laboratory OH USA Department of Electrical and Computer Engineering FAMU and FSU College of Engineering Tallahassee FL USA

An investigation into computer vision techniques is conducted using a procedure from nonlinear dynamics termed "stochastic resonance." This work involves concepts from detection theory, information theory and nonlinear dynamics. An information distance metric is synthesized which helps define the dependent measure to be used with the stochastic resonance optimization. Monte Carlo simulations show the efficacy of the proposed method. A class of test objects are presented to fairly evaluate the utility of the proposed methods introduced.

关键词： computer vision Stochastic resonance Strontium Signal processing Physics Information theory Application software Object recognition Noise figure Computational intelligence

来源：评论

学校读者我要写书评

暂无评论

Extrapolating Learned Manifolds for Human Activity Recognition

Extrapolating Learned Manifolds for Human Activity Recogniti...

引用

IEEE International Conference on Image Processing

作者： Tat-Jun Chin Liang Wang Konrad Schindler David Suter Institute for Infocomm Research Singapore Institute for Vision Systems Engineering Monash University VIC Australia Department of CSSE University of Melbourne Australia Computer Vision Laboratory ETH Zurich Switzerland

The problem of human activity recognition via visual stimuli can be approached using manifold learning, since the silhouette (binary) images of a person undergoing a smooth motion can be represented as a manifold in the image space. While manifold learning methods allow the characterization of the activity manifolds, performing activity recognition requires distinguishing between manifolds. This invariably involves the extrapolation of learned activity manifolds to new silhouettes -a task that is not fully addressed in the literature. This paper investigates and compares methods for the extrapolation of learned manifolds within the context of activity recognition. Also, the problem of obtaining dense samples for learning human silhouette manifolds is addressed.

关键词： Humans Extrapolation Image motion analysis Motion analysis Manifolds Image recognition Learning systems Sampling methods Shape Legged locomotion

来源：评论

学校读者我要写书评

暂无评论

A probabilistic framework for content-based diagnosis of retinal disease

A probabilistic framework for content-based diagnosis of ret...

引用

29th Annual International Conference of IEEE-EMBS, engineering in Medicine and Biology Society, EMBC'07

作者： Tobin, Kenneth W. Abdelrahman, Mohamed Chaum, Edward Govindasamy, V. Priya Karnowski, Thomas P. IEEE Image Science and Machine Vision Group Oak Ridge National Laboratory Oak Ridge TN 37831-6075 United States Electrical and Computer Engineering Dept. Tennessee Tech. University Cookeville TN 38505-0001 United States Department of Retinal Diseases Hamilton Eye Institute University of Tennessee Memphis TN 38163 United States

ISBN: (纸本)1424407885

Diabetic retinopathy is the leading cause of blindness in the working age population in the industrialized world. computer assisted analysis has the potential to assist in the early detection of diabetes by regular screening of large populations. The widespread availability of digital fundus cameras today is leading to the accumulation of large image archives of diagnosed patient data that captures historical knowledge of retinal pathology. Through this research we are developing a content-based image retrieval method to verify our hypothesis that retinal pathology can be identified and quantified from visually similar retinal images in an image archive. We will present diagnostic results for specificity and sensitivity on a population of 395 fundus images representing the normal fundus and 14 stratified disease states. © 2007 IEEE.

关键词： Diseases

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：