机构

• 长春光学精密机械与物... [3]

采集方式

• OAI收割 [3]

内容类型

• 会议论文 [3]

发表日期

• 2009 [1]
• 2006 [2]

学科主题

筛选

浏览/检索结果: 共3条，第1-3条 帮助 条数/页： 5101520253035404550556065707580859095100 排序方式： 请选择题名升序题名降序提交时间升序提交时间降序作者升序作者降序发表日期升序发表日期降序 Space optics remote sensor focusing components mechanics characteristic analysis based on FEM (EI CONFERENCE) 会议论文  OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Material and Device Technology for Sensors, June 17, 2009 - June 19, 2009, Beijing, China 作者:  Wang B.;  Ren J.-Y.;  Wang B. 收藏  |  浏览/下载：159/0  |  提交时间：2013/03/25 Space optical remote sensor is very important in many fields of science and military significance. It is widely applied. Space optical remote sensor design and manufacturing require precision and stability. Focusing mechanics is an important component of remote sensors. Focusing mechanics can guarantee the stability of the entire mechanics focusing accuracy  therefore the stability of research focusing mechanics is very important. In order to guarantee the space optics remote sensor focusing mechanics the stability  takes steps the space optics remote sensor focusing organization mechanics characteristic analysis from the classics contact theory. This article uses international general non-linear finite element analysis software ABAQUS to carry on mechanics characteristic analysis to the space optics remote sensor focusing mechanics. First acts according to the focusing mechanics unique feature  carries on the finite element to the structural model the grid division  the material attribute disposition and the boundary condition indeed grades. Then establishment contact non-linear finite element model  and to focusing organization finite element model infliction unit action. Like this contacts the result and the equivalent static analysis result which the nonlinear analysis obtains carries on the contrast and the analysis. This article last count result modality is 90HZ  satisfies the space optics remote sensor structure overall modality to request to be bigger than 50HZ.This article when carries on the dynamic analysis  extracts the structure kinetic energy and the acceleration curve. In the dynamic analysis obtained transient response analysis modality 70.5Hz  this also is bigger than 50HZ. The dynamic analysis indicated the structure dynamic stability has the distinct enhancement  has provided certain foundation for the space optics remote sensor following development work  reduced the overall system development cycle. 2009 SPIE.   A new approach for the removal of mixed noise based on wavelet transform (EI CONFERENCE) 会议论文  OAI收割 ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China 作者:  Li Y.;  Li Y. 收藏  |  浏览/下载：38/0  |  提交时间：2013/03/25 This paper proposed a new approach for the removal of mixed noise. There are many different ways in image denoising. Donoho et al have proposed a method for image de-noising by thresholding  ambiguity is often resulted in determining the correspondence of a modulus maximum to a singularity. In the light  and indeed  we combine the merits of the two techniques to form a new approach for the removal of mixed noise. At first  the application of their method to image denoising has been extremely successful. But the method of Donoho is based on the assumption that the type of noise is only additive Gaussian noise  we used wavelet singularity detection (WSD) technique to analyze singularities of signal and noise. According to the characteristic that wavelet transform modulus maxima of impulse noise rapidly decreases as the scale increases in wavelet domain  which is not successful for impulse noise. Mallat has also presented a method for signal denoising by discriminating the noise and the signal singularities through an analysis of their wavelet transform modulus maxima (WTMM). Nevertheless  it can be accurately located with multiscale space by going through dyadic orthogonal wavelet transform and removed. Furthermore the Gaussian noise is also removed through a level-dependent thresholding algorithm  the tracing of WTMM is not just tedious procedure computationally  algorithm. The experimental results demonstrate that the proposed method can effectively detect impulse noise and remove almost all of the noise while preserve image details very well.   A new segmentation method of CR images based on discrete wavelet transform and mathematics morphology (EI CONFERENCE) 会议论文  OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者:  Li Z.;  Li Z. 收藏  |  浏览/下载：68/0  |  提交时间：2013/03/25 In this paper  we propose a segmentation method of CR(computed radiography) images with being rid of under-segmentation and over-segmentation. An under-segmentation occurs when pixels belonging to different objects are grouped into a single region. Such errors are the most dangerous because they can invalidate the whole segmentation process. The phenomenon always takes place when we segment CR images because of the principle of CR. In order to depressed under-segmentation  we enhance the CR images using DWT (discrete wavelet transform) to get more detail of CR image features. As we enhance the CR image  the over-segmentation maybe occurs. Compared with under-segmentation  the over-segmentation occurs when a single objects is subdivided by segmentation into several region. For the purpose of preventing from the over-segmentation  we present a scheme for enhanced CR images based on watershed algorithm that solves over-segmentation problem. We use marker-based watershed algorithm. Together with gradient image and marker image  watershed segmentation can make sure to partition CR image into meaningful object and avoid further segmentation of homogeneous regions. The result of the proposed algorithm are compared with those of other standard methods. Experiments have shown a better result and indeed solved under-segmentation and over-segmentation problems.