检索结果-内蒙古大学图书馆

IEEE Southeastcon

作者： D.B. Dunn Jiangang Xia Ting-Chung Poon P.P. Banerjee Optical Image Processing Laboratory The Bradley Department of Electrical Engineering Virginia Polytechnic Institute and State University VA USA Virginia Polytechnic Institute and State University Blacksburg VA US Center for Applied Optics Department of Electrical and Computer Engineering University of Alabama Huntsville Huntsville AL USA

We present a novel and simple cascaded acousto-optic image processing system to perform image processing. The system consists of two imaging lenses and two acousto-optic modulators that are placed in series. Real time image processing is achieved by Bragg diffraction. computer simulation is given and compared to an optical image processing system which uses a single acousto-optic modulator.

关键词： image processing Optical imaging Lenses Optical modulation Fourier transforms Transfer functions Equations Laboratories computer simulation Acoustic beams

来源：评论

学校读者我要写书评

暂无评论

Performance enhancement in acousto-optic image processing

Performance enhancement in acousto-optic image processing

引用

IEEE Southeastcon

作者： P.P. Banejee D. Cao T.-C. Poon Dept. of Electr. & Comput. Eng. Alabama Univ. Huntsville AL USA Department of Electrical and Computer Engineering University of Alabama Huntsville Huntsville AL USA Optical Image Processing Laboratory The Bradley Department of Electrical Engineering Virginia Polytechnic Institute and State University Blacksburg VA USA

From the transfer functions of an acousto-optic (AO) cell, it is found that some basic image processing can be accomplished by using AO cells. Instead of frequency-plane filters, the AO cells are placed directly behind the object. The one dimensional edge enhancement results using one AO cell can be improved by using two acousto-optic cells which are put in tandem and with contra-propagating sound. The dominant second derivative operation obtained from the transfer function of the undiffracted order works like a one-dimensional Laplacian operator which enables improved edge enhancement.

关键词： image processing Numerical simulation Digital images image edge detection Propagation delay Laplace equations

来源：评论

学校读者我要写书评

暂无评论

An FDTD near- to far-zone transformation for scatterers buried in stratified grounds

引用

IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 1996年第8期44卷 1150-1157页

作者： Demarest, K Huang, ZB Plumb, R Radar Systems and Remote Sensing Laboratory Department of Electrical Engineering and Computer Science University of Kansas Lawrence KS USA

The finite-difference time-domain (FDTD) technique is being used with increasing frequency for modeling the scattering characteristics of buried objects, FDTD has, for some time, been able to model the near-zone scatterered fields of buried objects due to near-zone sources. This is adequate for modeling the scattered returns of ground-based ground-penetrating radars, but not for airborne radars, This paper describes an FDTD-compatible technique whereby far-zone scattered fields of objects buried in a stratified ground can be calculated, This technique uses the equivalence principle to model a buried object in terms of equivalent electric and magnetic currents, The fields radiated by these currents in the presence of a stratified ground are then calculated using the reciprocity theorem and the wed-known field equations for plane waves in stratified media, Numerical results are presented that show excellent agreement between this technique and both analytical and numerical results.

关键词： airborne radar electric current electromagnetic fields electromagnetic wave propagation electromagnetic wave scattering finite difference time-domain analysis radar cross-sections EM wave propagation analytical results buried objects burie Electromagnetic wave propagation Scattering RECIPROCITY THEOREM electric current Electromagnetic wave scattering airborne radar Buried object detection Finite difference time domain method Electromagnetic fields Electricity Radar cross section EQUIVALENCE PRINCIPLE wave propagation

来源：评论

学校读者我要写书评

暂无评论

Three-dimensional electromagnetic imaging of dielectric scatterers

引用

JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS 1996年第7期10卷 955-972页

作者： Chaturvedi, P Plumb, RG Huang, Z Demarest, KR Department of Electrical Engineering and Computer Science Radar Systems and Remote Sensing Laboratory The University of Kansas Lawrence KS 66045 USA

Solutions to two-dimensional electromagnetic imaging problems have been investigated extensively in recent years. Three-dimensional imaging problems have not been as well researched due to the inherent complexity of the formulation. Moreover, most of the work on imaging has concentrated on targets embedded in free space. In this paper, a technique for three-dimensional imaging based on an iterative Born method is presented. Targets with higher dielectric contrast for which the linear Born approximation is not valid can be imaged by using multiple iterations with this method. The extension of the technique to image a target buried in an inhomogeneous background is achieved by evaluating numerically the dyadic Green's function. Numerical simulations are presented to illustrate the applicability of the imaging algorithm. The results for a simulation are compared against those obtained with the inverse source method, and the difference in the performance of the two techniques is discussed. The convergence of the Born iterative method is also investigated in this paper.

关键词： Electromagnetic wave scattering

来源：评论

学校读者我要写书评

暂无评论

A system for vehicle classification from range imagery

A system for vehicle classification from range imagery

引用

Southeastern Symposium on System Theory

作者： Shiquan Peng C.A. Harlow Department of Electrical and Computer Engineering and Remote Sensing and Image Processing Laboratory Louisiana State University Baton Rouge LA USA

ISBN: (纸本)0818673524

In this project we consider automated vehicle location and classification systems. Current systems which utilize loop detectors or video cameras have deficiencies. Video based systems are sensitive to environmental conditions and do not perform well in vehicle classification. The new generation of range or distance sensors that are being developed offer the promise of sensors which are not sensitive to lighting conditions and provide information which should give better vehicle detection and classification percentages than current systems. The focus of this project is to develop an automated vehicle location and classification system based upon imagery obtained from range sensors. image analysis operators and classification methods are developed for vehicle classification. Preliminary results indicate that accurate vehicle classification can be obtained.

关键词： Vehicle detection Radar detection Sensor systems Costs Infrared detectors Laser radar image processing Road transportation Machine vision Surveillance

来源：评论

学校读者我要写书评

暂无评论

A hybrid formulation for the probe-to-patch attachment-mode current for rectangular microstrip antennas

引用

IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 1996年第5期44卷 677-686页

作者： Chatterjee, D Plumb, RG Department of Electrical Engineering and Computer Science Systems and Remote Sensing Laboratory University of Kansas Lawrence KS USA

In this paper, we present a hybrid representation for the attachment-mode current existing on the surface of a coaxially fed rectangular microstrip patch antenna, The hybrid representation consists of a one- or two-term residue and an eigenfunction series which gives the attachment-mode current at all points on-the patch surface, including the probe-to-patch junction, It is numerically demonstrated that the residue and eigenfunction series blend smoothly in the close vicinity of the Stokes region which includes the probe-to-patch junction, The Stokes region is a very narrow region over which the attachment-mode current changes rapidly, The residue and eigenfunction series are used outside and within this Stokes region, respectively, This hybrid representation can be used in either spectral- or space-domain techniques for a full-wave solution to the microstrip antenna problem, The residue series is obtained by using an equivalent contour integral representation of the infinite eigenfunction series, which subsequently reduces to the Watson transform under the assumption of a slightly lossy substrate, At or near the Stokes regions the residue series is inadequate,as it cannot model the rapidly varying junction currents there, Examination of the residue series shows that the attachment mode is a superposition of exponentially attenuated, leaky, surface-traveling modes;This hybrid representation is expected to provide the optimum trade-off between speed and accuracy for computations involving electrically large finite arrays.

关键词： Microstrip antennas Feeds Microstrip antenna arrays Coaxial components Eigenvalues and eigenfunctions Predictive models Frequency Probes Impedance Patch antennas

来源：评论

学校读者我要写书评

暂无评论

A new time series classification approach

引用

SIGNAL processing 1996年第2期54卷 191-199页

作者： Plataniotis, KN Androutsos, D Venetsanopoulos, AN Lainiotis, DG Department of Electrical and Computer Engineering Digital Signal & Image Processing Laboratory University of Toronto 10 King's College Rd. Toronto Ontario M5S 3G4 Canada Intelligent Systems Technology 3207 S. Hwy. A1A Melbourne Beach FL-32951 USA

A new, robust and computationally attractive approach to the problem of time series classification is discussed in this paper. Both the Bayesian as well as a new adaptive classification scheme for source selection are... 详细信息

关键词： time series classification neural networks logistic function

来源：评论

学校读者我要写书评

暂无评论

remote sensing of the near surface-ocean wind vector under low-wind conditions using scatterometry

Remote sensing of the near surface-ocean wind vector under l...

引用

IEEE International Symposium on Geoscience and remote sensing (IGARSS)

作者： J. Carswell W. Donnelly R. McIntosh Microwave Remote Sensing Laboratory Department of Electrical Computer Engineeringersity of Massachusetts Amherst MA USA Microwave Remote Sensing Laboratory Department of Elecetrical Computer Engineering University of Massachusetts Amherst MA USA Microwave Remote Sensing Laboratory Department of Electrical Computer Engineering University of Massachusetts Amherst MA USA

The University of Massachusetts collected C- and Ku-band ocean backscatter measurements at 21.0/spl deg/, 31.0/spl deg/, 41.5/spl deg/ and 52.0/spl deg/ incidence, using a C-band and a Ku-band conical scanning airborne scatterometer. These high spatial resolution backscatter measurements differ significantly, for low-wind cases, from the predicted responses of the CMOD4 and SASS-II model functions. The nulls in the azimuthal backscatter response tend to decrease at a much faster rate than predicted as the winds decrease below 5 m s/sup -1/, the measured backscatter response does not follow a power-law relationship with wind speed nor with wind stress, and a cutoff wind speed, below which the backscatter drops to immeasurable quantities, is present. These characteristics are predicted by the Donelan and Pierson (1987) model, and comparing the measured results with this model shows good agreement. However, when the spatial resolution of the measurements are degraded to an area equivalent to that of satellite-based measurements, the deep nulls and fast fall off rate are no longer present. Such effects may bias the backscatter measurements from satellite-based platforms towards the higher winds within the footprint, and thus overestimate the wind speed.

关键词： remote sensing Sea measurements Backscatter Wind speed Predictive models Spatial resolution Wind forecasting Velocity measurement Area measurement Sea surface

来源：评论

学校读者我要写书评

暂无评论

3D segmentation and labeling using self-organizing Kohonen network for volumetric measurements on brain CT imaging to quantify TBI recovery

3D segmentation and labeling using self-organizing Kohonen n...

引用

Annual International Conference of the IEEE engineering in Medicine and Biology Society (EMBC)

作者： M.N. Ahmed A.A. Farag Computer Vision and Image Processing Laboratory Department of Electrical Engineering University of Louisville Louisville KY USA

In this paper, we present a new system to segment and label CT brain slices using a self-organizing Kohonen network. Our aim is to extract reliable and robust measures from CT images of Traumatic Brain Injury (TBI) patients that can accurately describe the morphological changes in the brain as recovery progresses. Segmentation is performed by assigning a feature pattern to each voxel, consisting of a scaled family of differential geometrical invariant features. The invariant feature pattern is input to Kohonen network for an unsupervised classification of the voxels into regions.

关键词： Labeling Volume measurement image segmentation Computed tomography Layout Electric variables measurement engineering in Medicine and Biology Society Brain injuries Data mining Filters

来源：评论

学校读者我要写书评

暂无评论

Dual-frequency three-dimensional images of clouds

Dual-frequency three-dimensional images of clouds

引用

IEEE International Symposium on Geoscience and remote sensing (IGARSS)

作者： J.M. Firda S.M. Sekelsky R.E. McIntosh Microwave Remote Sensing Laboratory Department of Electrical & Computer Engineering University of Massachusetts Amherst MA USA

This paper presents a method of forming three-dimensional representations of clouds and precipitation by combining series of two dimensional scans. In April of 1995 the Cloud Profiling Radar System (CPRS) collected dual-frequency Doppler radar data of several cloud scenarios. images of reflectivity and linear depolarization ratio are presented from different viewpoints of a precipitating cloud with a well defined melting layer.

关键词： Clouds Doppler radar Spaceborne radar Radar imaging Radar antennas Radar polarimetry Reflectivity Frequency remote sensing Antenna measurements

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：