检索结果-内蒙古大学图书馆

2nd conference on image reconstruction from incomplete data

作者： Abrams, MC Cain, SC ITT Industries Inc. (United States) Indiana Univ.-Purdue Univ./Fort Wayne (United States)

ISBN: (纸本)0819445592

In this paper, a Bayesian-based image reconstruction scheme is utilized for estimating a high resolution temperature map of the top of the earth's atmosphere using the GOES-8 (Geostationary Operational Environmental Satellite) imager infrared channels. By simultaneously interpolating the image while estimating temperature, the proposed algorithm achieves a more accurate estimate of the sub-pixel temperatures than could be obtained by performing these operations independently of one another. The proposed algorithm differs from other Bayesian-based image interpolation schemes in that it estimates brightness temperature as opposed to image intensity and incorporates a detailed optical model of the GOES multi-channel imaging system. The temperature estimation scheme is compared to deconvolution via pseudo-inverse filtering using two metrics. One metric is the mean squared temperature error. This metric describes the radiometric accuracy of the image estimate. The second metric is the recovered Modulation Transfer Function (MTF) of the image estimate. This method has traditionally been used to evaluate the quality of image recovery techniques. It will be shown in this paper that there is an inconsistency between these two metrics in that an image with high spatial frequency content can be reconstructed with poor radiometric, accuracy. The ramifications of this are discussed in order to evaluate the two metrics for use in quantifying the performance of image reconstruction algorithms.

关键词： Imaging systems image restoration reconstruction algorithms Sensors image resolution Modulation transfer functions Radiometry data modeling Satellite imaging Satellites

来源：评论

学校读者我要写书评

暂无评论

Processing synthetic aperture sonar data from novel hydrophone arrays

Processing synthetic aperture sonar data from novel hydropho...

引用

conference on image reconstruction from incomplete data

作者： Millane, RP Gough, PT Univ Canterbury Dept Elect & Elect Engn Christchurch 1 New Zealand

ISBN: (纸本)0819437689

In synthetic aperture sonar, the highest platform speed is limited as a result of the low speed of sound in water and the requirement for adequate sampling in the along-track direction. This can result in slow seafloor mapping, The highest allowable platform speed can be increased by using a linear array of hydrophones. The signal-to-noise can also be improved by using multiple sets of hydrophone arrays. Maximum-likelihood estimation of images using data from sets of hydrophone arrays that each undersample the underlying signal to different degrees is described, Simulations for synthetic aperture sonar imaging show that this improves the images obtained over those from a single array.

关键词： synthetic aperture sonar aliasing maximum-likelihood

来源：评论

学校读者我要写书评

暂无评论

Self Tuning Kalman Filter Estimation of Atmospheric Warp

Self Tuning Kalman Filter Estimation of Atmospheric Warp

引用

conference on image reconstruction from incomplete data V

作者： Tahtali, Murat Lambert, Andrew Fraser, Donald UNSW ADFA Sch Aerosp Civil & Mech Engn Canberra ACT 2600 Australia UNSW ADFA Sch Informat Technol & Elect Engn Canberra ACT 2600 Australia

ISBN: (纸本)9780819472960

In our previous work we have demonstrated that the perceived wander of image intensities as seen through the windows" of each pixel due to atmospheric turbulence can be modelled as a simple oscillator pixel-by-pixel and a linear Kalman filter (KF) can be finetuned to predict to a certain extent short term future deformations. In this paper, we are expanding the Kalman filter into a Hybrid Extended Kalman filter (HEKF) to fine tune itself by relaxing the oscillator parameters at each individual pixel. Results show that HEKF performs significantly better than linear KF.

关键词： Kalman filter image registration shiftmaps atmospheric warp image restoration

来源：评论

学校读者我要写书评

暂无评论

Unified imaging theory for X-ray and acoustic computerized tomography

Unified imaging theory for X-ray and acoustic computerized t...

引用

conference on image reconstruction from incomplete data III

作者： Liu, PY Wang, G Boyer, A Stanford Univ Dept Radiat Oncol Stanford CA 94305 USA

ISBN: (纸本)0819455008

X-ray computerized tomography (CT) and acoustic CT are two main medical imaging modalities based on two intrinsically different physical phenomena. X-ray CT is based on xray's attenuation when x-ray passes through medium. It has been well known that the Radon transform is the imaging theory for x-ray CT. Photoacoustic CT is a type of acoustic CT, which is based on differentiating electromagnetic energy absorption among media. In 1998 a new 3D reconstruction concept, the P-transform, was proposed to serve the imaging theory for photoacoustic CT. In this paper it was rigorously proved that both x-ray CT and photoacoustic CT are governed by a unified imaging theory. 3D data acquisition can be completed in 2pi stereoangle. This new imaging theory realized, in part, the dream of all physicists, including Albert Einstein, who have long believed that our world is ultimately governed by few simple rules.

关键词： image reconstruction P-transform Radon transform

来源：评论

学校读者我要写书评

暂无评论

Newton-style optimization for emission tomographic estimation

引用

JOURNAL OF ELECTRONIC IMAGING 2000年第3期9卷 269-282页

作者： Thibault, JB Sauer, K Bouman, C Global Technol Operat Gen Elect Med Syst Waukesha WI 53188 USA Univ Notre Dame Dept Elect Engn Notre Dame IN 46556 USA Purdue Univ Sch Elect Engn W Lafayette IN 47907 USA

Emission computed tomography is widely applied in medical diagnostic imaging, especially to determine physiological function. The available set of measurements is, however, often incomplete and corrupted, and the quality of image reconstruction is enhanced by the computation of a statistically optimal estimate. Most formulations of the estimation problem use the Poisson model to measure fidelity to data. The intuitive appeal and operational simplicity of quadratic approximations to the Poisson log likelihood make them an attractive alternative, but they imply a potential loss of reconstruction quality which has not often been studied. This paper presents quantitative comparisons between the two models and shows that a judiciously chosen quadratic, as part of a short series of Newton-style steps, yields reconstructions nearly indistinguishable from those under the exact Poisson model. (C) 2000 SPIE and IS&T. [S1017-9909(00)00502-X].

关键词： Tomography image analysis Head Optimization (mathematics) reconstruction algorithms Positron emission tomography Single photon emission computed tomography Expectation maximization algorithms Photon counting Signal to noise ratio

来源：评论

学校读者我要写书评

暂无评论

JSR-NET: A DEEP NETWORK FOR JOINT SPATIAL-RADON DOMAIN CT reconstruction from incomplete data 44

JSR-NET: A DEEP NETWORK FOR JOINT SPATIAL-RADON DOMAIN CT RE...

引用

44th IEEE International conference on Acoustics, Speech and Signal Processing (ICASSP)

作者： Zhang, Haimiao Dong, Bin Liu, Baodong Peking Univ Beijing Peoples R China Chinese Acad Sci Beijing Peoples R China Univ Chinese Acad Sci Beijing Peoples R China

ISBN: (纸本)9781479981311

CT image reconstruction from incomplete data, such as sparse views and limited angle reconstruction, is an important and challenging problem in medical imaging. This work proposes a new deep convolutional neural network (CNN), called JSR-Net, that jointly reconstructs CT images and their associated Radon domain projections. JSR-Net combines the traditional model based approach with deep architecture design of deep learning. A hybrid loss function is adopted to improve the performance of the JSR-Net making it more effective in protecting important image structures. Numerical experiments demonstrate that JSR-Net outperforms some latest model based reconstruction methods, as well as a recently proposed deep model.

关键词： Joint spatial-Radon domain reconstruction Sparse-view CT Limited angle CT Convolutional neural networks Deep learning

来源：评论

学校读者我要写书评

暂无评论

Oblique surface reconstruction to approximate cone-beam helical data in multi-slice CT

Oblique surface reconstruction to approximate cone-beam heli...

引用

conference on image reconstruction from incomplete data

作者： Chen, LG Heuscher, DJ Liang, Y Purdue Univ Sch Hlth Sci W Lafayette IN 47907 USA

ISBN: (纸本)0819437689

Multi-slice helical beam scanning involves cone-beam geometry. The primary advantages for use of divergent cone-beams include reduced data acquisition, improved image resolution and optimized photon utilization. Due to the complexity of 3-dimensional cone-beam reconstruction, approximate algorithms have been sought to handle the cone-beam reconstruction. This paper presents a new approximate algorithm termed as oblique surface reconstruction (OSR). Theoretical considerations as well as the reconstruction of simulated phantom data in comparison to the current standard 180 degrees LI are presented. OSR is shown to be effective and practical to generate images with diagnostic quality.

关键词： spiral CT multi-slice CT cone-beam reconstruction oblique surface reconstruction

来源：评论

学校读者我要写书评

暂无评论

Determining wind fields in atmospheric mountain waves using sailplane flight data

Determining wind fields in atmospheric mountain waves using ...

引用

conference on image reconstruction from incomplete data viI

作者： Zhang, Ni Millane, Rick P. Enevoldson, Einar Murray, James E. Univ Canterbury Dept Elect & Comp Engn Computat Imaging Grp Christchurch 1 New Zealand NASA Dryden Flight Res Ctr Edwardsville IL 93523 USA

ISBN: (纸本)9780819492173

The problem of estimating wind velocities from limited flight data recordings is considered, with application to sailplane flights in high-altitude atmospheric mountain waves. Sailplane flight recorders routinely measure only GPS position and the problem is highly underdetermined. The nature of this problem is studied and a maximum a posteriori estimator is developed using prior information on the wind velocity and the sailplane airspeed and heading. The method is tested by simulation and by application to sailplane flight data.

关键词： Maximum a posteriori wind velocity aircraft sailplane mountain wave atmospheric wave

来源：评论

学校读者我要写书评

暂无评论

TOMOGRAPHIC image reconstruction from incomplete INFORMATION BY CONVEX PROJECTIONS AND DIRECT FOURIER INVERSION: SUGGESTED APPLICATIONS TO SPOTLIGHT-MODE SYNTHETIC APERTURE RADAR (SAR) IMAGING.

TOMOGRAPHIC IMAGE RECONSTRUCTION FROM INCOMPLETE INFORMATION...

引用

Proceedings of the 1984 conference on Information Sciences and Systems.

作者： Sezan, M.Ibrahim Stark, Henry Rensselaer Polytechnic Inst Troy NY USA Rensselaer Polytechnic Inst Troy NY USA

Spotlight-mode synthetic aperture radar (SAR) imaging has a close resemblance to tomographic image reconstruction from incomplete view data. A new algorithm (PRDF), designed for reconstructing tomographic imagery from incomplete view data, is described. The results of applying the PRDF algorithm to reconstruct a human thorax cross-section from simulated X-ray projection data are furnished. An algorithm which is basically a special case of PRDF is suggested for spotlight-mode SAR imaging.

关键词： image PROCESSING

来源：评论

学校读者我要写书评

暂无评论

Obtaining three dimensional probability density functions from projected data

Obtaining three dimensional probability density functions fr...

引用

conference on image reconstruction from incomplete data

作者： Jaffe, JS Univ Calif San Diego Scripps Inst Oceanog Marine Phys Lab La Jolla CA 92093 USA

ISBN: (纸本)0819437689

In many experimental observation systems where the goal is to record a 3-dimensional observation of an object, or a set of objects, a lower dimensional projection of the intended subject is obtained. In some situations only the statistical properties of such objects is desired: the three dimensional probablility density function. This article demonstrates that under special symmetries this function can be obtained from a two dimensional probability density function which, has been obtained from the observed, projected data. Standard tomographic theorems can be used to guarantee the uniqueness of this function and a natural basis set can be used in computing the three dimensional function from the two dimensional projection. Here, the theory of this inversion is explored from a theoretical and numerical point of view with some examples of data functions taken from scientific experiments

关键词： tomography probability density function inverse theory

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：