检索结果-内蒙古大学图书馆

CONF ON VISUAL COMMUNICATIONS AND IMAGE PROCESSING : IMAGE PROCESSING

作者： HWANG, H HADDAD, RA Polytechnic Univ. (United States)

ISBN: (纸本)0819407437

We present two robust adaptive median filters with variable window size which are capable of removing a mixture of positive and negative impulse noise while preserving sharpness of an edge. In the first case, we assume that each pixel at (i J ) is corrupted by an impulse with probabilitype independent of other pixels corrupted or not. The impulse corrupted pixel takes on the minimum pixel value smm with probability q or the maximum pixel value mwith probability 1 when the original pixel s is corrupted by a negative or a positive impulse, respectively. Let {x } be the noise corrupted image. Then I e,1 with Pe xii = 1 with 1 The RAMF algorithm is based on a test for the presence of an impulse at the center pixel followed by a test for the detection of residual impulse in the median filter output. In the second model, the noise corrupted pixel is x =s +n1 , where n1 is iid impulsive noise having Laplacian, or Cauchy, or a mixture of Gaussian and Cauchy distributions. The SAMF algorithm in this instance detects the width of the impulse and adjusts the window accordingly until the noise is eliminated. These algorithms were tested on standard images. The RAMF is shown to be supenor to the nonlinear mean L filter[1] while the SAMF is better performing and simpler than [in's adaptive scheme[3].

关键词： Digital filtering Image filtering Image processing Nonlinear filtering Visual communications Quantum efficiency Aluminum Computer engineering detection and tracking algorithms Field emission displays

来源：评论

学校读者我要写书评

暂无评论

REAL-TIME MAP-BUILDING FOR FAST MOBILE ROBOT OBSTACLE AVOIDANCE

REAL-TIME MAP-BUILDING FOR FAST MOBILE ROBOT OBSTACLE AVOIDA...

引用

CONF ON MOBILE ROBOTS 5

作者： BORENSTEIN, J KOREN, Y Univ. of Michigan (United States)

ISBN: (纸本)0819404551

This paper introduces HIMM (histogramic in-motion mapping) a new method for real-time map building with a mobile robot in motion. HIMM represents data in a two-dimensional array (called a histogram gjid) that is updated through rapid continuous sampling of the onboard range sensors during motion. Rapid in-motion sampling results in a statistical map representation that is well-suited to modeling inaccurate and noisy range-sensor data. HIMM is integral part of an obstacle avoidance algorithm and allows the robot to immediately use the mapped information in real-time obstacleavoidance. The benefits of this integrated approach are twofold: (1) quick accurate mapping and (2) safe navigation of the robot toward a given target. HIMM has been implemented and tested on a mobile robot. Its dual functionality was demonstrated through numerous tests in which maps of unknown obstacle courses were created while the robot simultaneously performed real-time obstacle avoidance maneuvers at speeds of up to 0. 78m/sec.

关键词： Sensors Mobile robots Ultrasonics Distance measurement Data modeling Acoustics Motion models Associative arrays Statistical modeling detection and tracking algorithms

来源：评论

学校读者我要写书评

暂无评论

SCANNING STRATEGIES FOR TARGET detection

SCANNING STRATEGIES FOR TARGET DETECTION

引用

CONF ON DATA STRUCTURES AND TARGET CLASSIFICATION

作者： GERTNER, I ZEEVI, Y Rutgers Univ. (United States)

ISBN: (纸本)0819405795

This paper presents a new method of image scanning based on the solution of a set of linear congruences, called generalized raster scan (GRS), which is a generalization of the classic raster scan. The main properties of the GRS and algorithms for its implementations are elaborated. The GRS can be regarded as a linear combination of raster and random scans. The new method is in particular instrumental in applications where on-line acquisition and hierarchical processing is of importance. As such, the new approach is suitable for target finding, clustering, and visual inspection. It is also suitable for image processing and/or transmission with progressive resolution.

关键词： Raster graphics Target detection Image processing Data acquisition Algorithm development detection and tracking algorithms Fourier transforms Image resolution Image compression Target acquisition

来源：评论

学校读者我要写书评

暂无评论

SCHUR RLS ADAPTIVE FILTERING USING SYSTOLIC ARRAYS

SCHUR RLS ADAPTIVE FILTERING USING SYSTOLIC ARRAYS

引用

CONF ON ADAPTIVE SIGNAL PROCESSING

作者： STROBACH, P Siemens AG (Germany)

ISBN: (纸本)0819406937

An interpretation of the tracking behavior of fast RLS adaptive filters is given. It is shown that the overall performance of an RLS adaptive filter is solely dependent on the forgetting function, which is involved in coefficient updating. Fast RLS adaptive filters restrict themselves to simple exponential or rectangular forgetting functions. Their tracking behavior is quite limited and sometimes even disappointing when compared to the much simpler LMS algorithm. These limitations can be circumvented with the advent of Schur RLS adaptive filters which allow the application of arbitrarily shaped forgetting functions in the coefficient updating process. Schur RLS adaptive filters are closely connected to the theory of discrete transmission lines. They are flexible in their possible configuration and share excellent structural and numerical properties, which make them highly attractive candidates for concurrent implementations. Systolic arrays of the Schur RLS adaptive filters are presented and their performance is demonstrated with a typical example.

关键词： Digital filtering Filtering (signal processing) Signal processing Electronic filtering Radon Modulation detection and tracking algorithms Digital signal processing Algorithm development Receivers

来源：评论

学校读者我要写书评

暂无评论

NEURAL NETWORKS APPLICATION IN AUTONOMOUS PATH GENERATION FOR MOBILE ROBOTS

NEURAL NETWORKS APPLICATION IN AUTONOMOUS PATH GENERATION FO...

引用

1990 MIDWEST CONF ON APPLICATIONS OF OPTICAL ENGINEERING : ( OE/MIDWEST 90 )

作者： POURBOGHRAT, F Southern Illinois Univ./Carbondale (United States)

ISBN: (纸本)0819404772

The problem of collision-free path generation for mobile robots is considered This task is formulated into an optimization problem for which a recurrent neural network similar to Hopfield''s is useiL The outputs of the units in the network correspond to the position of some intermediate points on the path which would be connected by straight lines. The steady-state values of the outputs of the units in the network correspond to the coordinates of the position of the intermediate points on the shortest collision-free path to the targets To derive the dynamics of the network first an eneri function corresponding to the distance from the target the total length of the path and the degree of closeness to the obstacles is derived1 The dynamics of the network is then derived according to a gradient descent algorithms 1 .

关键词： Neural networks Mobile robots Optical engineering Algorithm development Collision avoidance Evolutionary algorithms Robots detection and tracking algorithms Electrical engineering Robotics

来源：评论

学校读者我要写书评

暂无评论

EFFECT OF IMAGE SIZE AND CONTRAST ON THE RECOGNITION OF INSECTS IN RADIOGRAMS

EFFECT OF IMAGE SIZE AND CONTRAST ON THE RECOGNITION OF INSE...

引用

CONF ON OPTICS IN AGRICULTURE

作者： SCHATZKI, TF KEAGY, PM U.S. Dept. of Agriculture (United States)

ISBN: (纸本)0819404462

Radiograms of individual wheat kernels some of which contained immature insects (weevils moths or borers) were captured using microscopy into a 512x512x8 frame buffer 16. 4 pm/pixel. The resulting image was reduced repeatedly to half-size to produce collages containing 4 16 64 and 256 reduced images. Half the collages contained one and half no insect. Subjects were shown sets of 500 images on a 13 " monitor and were asked to determine whether an insect was present. Since hidden insects are typically characterized by a light insect inside a dark ring (the hole) inside a light kernel we measured the size of the recognizable region as the length (major diameter) and width of the hole in pixels in the reduced image. Contrast was represented as the square root of the variance of the pixel intensity along length or width. We find that recognition can be predicted to 80-90 by length alone contrast or width add little. The length for 50 recognition amounts to 12. 20. 6 22. 10. 7 and 19. 80. 6 pixels for weevils moths and borers resp. It is suggested that insect recognition depends on recognizing as yet unknown image features which are lost when images are reduced beyond this size. 1."

关键词： Agriculture detection and tracking algorithms Image enhancement Image processing Data modeling Target recognition Optical inspection Radio optics Radiography Visualization

来源：评论

学校读者我要写书评

暂无评论

CONTROL OF FLEXIBLE, KINEMATICALLY REDUNDANT ROBOT MANIPULATORS

CONTROL OF FLEXIBLE, KINEMATICALLY REDUNDANT ROBOT MANIPULAT...

引用

CONF ON COOPERATIVE INTELLIGENT ROBOTICS IN SPACE

作者： NGUYEN, LA WALKER, ID DEFIGUEIREDO, RJP Rice Univ. (United States) Univ. of California/Irvine (United States)

ISBN: (纸本)0819404543

The use of kinematic redundancy in control algorithms to avoid singularities evade obstacles minimize joint torques manipulator kinetic energy end effector contact forces etc. . . has been among the most active research topics in the field of robotics in the past few years. However these approaches have been associated mainly with rigid manipulators where there is no unpredictable flexible motions. When dealing with flexible manipulators the flexibility of the system will cause undesired inaccuracy in end effector motion. If these manipulators are kinematically redundant their kinematic redundancy can be used to compensate for the end effector motion inaccuracy and in many cases help damp out the vibrations. This paper examines this issue and introduces new control algorithms designed to regulate the flexibility while maintaining precise tracking of the end effector trajectory. The dynamic model used is a special case of the general multi-body dynamics designed to maximize its computational efficiency.

关键词： Robotics Space robots Control systems Kinematics Fourier transforms Motion controllers Computer simulations Numerical simulations detection and tracking algorithms Motion models

来源：评论

学校读者我要写书评

暂无评论

Two methods of fractal dimension computation applied to millimeter wave radar stationary target detection 16

Two methods of fractal dimension computation applied to mill...

引用

16th International Conference on Infrared and Millimeter Waves 1991

作者： Butterfield, Jill I. Georgia Tech Research Institute Georgia Institute of Technology AtlantaGA30332 United States

In recent years, millimeter wave (MMW) radar stationary target detection algorithms have employed methods which exploit the geometric nature of targets and clutter in order to eliminate high amplitude clutter returns. Traditional adaptive amplitude thresholding techniques (e.g., constant false alarm rate, CFAR, processing) could not yield the desired high probabilities of detection because thresholds had to be set high enough to eliminate the high amplitude clutter. Man-made targets and high amplitude clutter tend to have different geometrical characteristics. In order to improve detection results while keeping false alarms to a minimum, these differences must be exploited.

关键词： Fractal analysis Extremely high frequency Radar Target detection detection and tracking algorithms Image resolution

来源：评论

学校读者我要写书评

暂无评论

detection AND tracking OF LOW-OBSERVABLE TARGETS THROUGH DYNAMIC-PROGRAMMING

DETECTION AND TRACKING OF LOW-OBSERVABLE TARGETS THROUGH DYN...

引用

CONF ON SIGNAL AND DATA PROCESSING OF SMALL TARGETS 1990

作者： ARNOLD, J PASTERNACK, H SRI International (United States)

ISBN: (纸本)0819403563

A dynamic programming (DP) technique has been developed for the detection of subpixel-sized, low-SNR targets observed by mosaic imaging sensors. The primary advantages of DP are its sensitivity to weak targets along with its robustness to target maneuvers and sensor instabilities. Such enhancements are achieved by performing target data association and detection in a single optimization procedure. To the extent that the target motion and noise behavior can be accurately modeled, the DP algorithm is shown to be optimal for this task. A prototype JR tracking system based on the DP approach was developed and tested for a step-staring IR camera application. Performance analysis indicates a sensitivity improvement of several dB over conventional sequential detection tracking approaches.

关键词： Target detection detection and tracking algorithms Sensors Signal processing Cameras Computer programming Data processing Optical filters 3D acquisition Image filtering

来源：评论

学校读者我要写书评

暂无评论

USE OF SPATIAL LIGHT MODULATORS IN FREQUENCY-MODULATION RETICLE TRACKERS

引用

OPTICAL ENGINEERING 1990年第11期29卷 1398-1403页

作者： DRIGGERS, RG HALFORD, CE BOREMAN, GD UNIV CENT FLORIDA CTR RES ELECT OPT & LASERSDEPT ELECT ENGNORLANDOFL 32816

Advances in spatial light modulator (SLM) technology have resuited in an active search for signal processing algorithms for use with SLMs in incoherent electro-optical systems. This paper presents an effective means of generating tracking algorithms for locating small targets with a single detector using FM reticle theory. A simple "barrel transformation" of a spinning FM reticle pattern to an SLM is shown to allow tracking systems to be constructed with solid state devices and avoids the need for moving parts. Also, SLMs allow the FM patterns to change over time, allowing adaptive interrogation of targets in a particular region of a system's field of view.

关键词： Spatial light modulators Reticles Frequency modulation Fermium Signal detection Modulation Sensors detection and tracking algorithms Electronics Target detection

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：