检索结果-内蒙古大学图书馆

IEEE Nuclear Science Symposium/Medical Imaging Conference (NSS/MIC)/18th International Workshop on Room-Temperature Semiconductor X-Ray and Gamma-Ray Detectors

作者： Bilgot, Anne Desbat, Laurent Perrier, Valerie UJF Grenoble 1 CNRS TIMC IMAG UMR 5525 F-38041 Grenoble France Grenoble INP CNRS TIMC F-38041 Grenoble France

ISBN: (纸本)9781467301206

We consider the Filtered Back Projection reconstruction method in the case of interior data in Computerized Tomography. In this framework we prove that the difference between the FBP reconstruction and the measured function is a continuous function. This demonstrates that the FBP reconstruction contains the discontinuities of the measured image. Thus FBP can be considered as a local reconstruction method in CT. We show numerical experiments on both simulated and real data.

关键词： X-Ray Computed Tomography reconstruction algorithm Tomography discontinuities backprojection observational data Continuous Function

来源：评论

学校读者我要写书评

暂无评论

DEM Construction and Calibration of Hyperspectral Image Data Using Pairs of Radiance Images

DEM Construction and Calibration of Hyperspectral Image Data...

引用

7th International Symposium on Image and Signal Processing and Analysis (ISPA)

作者： Grumpe, Arne M. Woehler, Christian TU Dortmund Fac Elect Engn & Informat Technol Image Anal Grp Otto Hahn Str 4 D-44227 Dortmund Germany

ISBN: (纸本)9789531841597

In lunar remote sensing, the analysis of the spectral reflectance of iron-bearing minerals is a widely used method. For an accurate calibration, elevation information about the surface has to be known. In this paper we present a framework for the reconstruction of digital elevation maps (DEM) from hyperspectral imagery and preexisting elevation data of lower lateral resolution. The reconstruction algorithm consists of a combined photoclinometry and shape from shading scheme, which is extended towards photometric stereo using multiple images. In order to register images of the same surface region acquired under different illumination conditions, an image registration approach is derived from the DEM construction methods. Image registration is performed in the illumination-invariant surface gradient space and is therefore able to cope with images taken under different illumination conditions. Finally, the calibration of hyperspectral imagery based on the DEM is demonstrated by the analysis of extracted spectral features.

关键词： hyperspectral imagery image data images multiple image reconstruction algorithm Region of surface spectral reflectance image registration radiance Calibration Lighting illumination

来源：评论

学校读者我要写书评

暂无评论

RESEARCHES ON THE KEY TECHNOLOGIES FOR TOMOGRAPHIC GAMMA SCANNING

RESEARCHES ON THE KEY TECHNOLOGIES FOR TOMOGRAPHIC GAMMA SCA...

引用

18th International Conference on Nuclear Engineering (ICONE-18)

作者： Zhang Quanhu Hui Weihua Li Feng Gu Zhongmao Qian Shaojun Xian Res Inst High Tech Xian 710025 Shaanxi Peoples R China China Inst Atom Energy Beijing 102413 Peoples R China

ISBN: (纸本)9780791849316

Tomographic Gamma Scanning (TGS) method is one of the most advanced non-destructive assay (NDA) methods. But for measuring heterogeneously distributed media with medium- and high-density, there are still three main problems: experiment's method of the calibration of detection efficiency of TGS is more difficult and complicated because of large voxels, "point-to-point" model and average model can't calculate high-density samples accurately in transmission image reconstruction and computational cost is very large for correction factor in emission image. Calibration of detection efficiency using Monte Carlo method shorten calibration cycle greatly, a new Monte Carlo statistical iteration in TGS transmission image reconstruction method which is based on MC calculation and Numerical Analysis is presented, give a chance for measuring high-density samples;the division method and pre-calculation method in reconstructing TGS emission image is used which saves a great lot of computation time and provide a fast reconstruction algorithm for emission image. Above methods apply to TGS experiment device, the relative errors between experiment and MC calibration were less 5%;the relative errors between reconstructed values and the reference values were less than 4% in transmission image;the corrected experimental results were compared to the standard values and the relative deviation was found to be 7%. It took no more than one hour to complete the reconstruction of TGS emission image for a sample model with 3x3x3 voxels using a 2.0G computer.

关键词： Image communication systems computational time detection efficiency reconstruction algorithm division method reference value Normal Range Keys Image images Imagery (Psychotherapy) relative errors emission Emissions Numerical Analysis

来源：评论

学校读者我要写书评

暂无评论

Solving the Two Color Problem: An Heuristic algorithm

引用

14th International Workshop on Combinatorial Image Analysis (IWCIA)

作者： Barcucci, Elena Brocchi, Stefano Frosini, Andrea Univ Florence Dipartimento Sistemi & Informat I-50134 Florence Italy

ISBN: (纸本)9783642210730

The 2-color problem in discrete tomography requires to construct a 2-colored matrix consistent with a given set of projections representing the number of elements of each color in each one of its rows and columns. In this paper, we describe an heuristic algorithm to find a solution of the 2-color problem, that has been recently proved to be NP-complete. The algorithm starts by computing a solution where elements of different colors may overlap, and then it proceeds in searching for switches that leave unaltered the projections but remove the overlaps. Experimental results show that this heuristic approach finds a solution in a short computational time to almost all the randomly generated 2-color instances, and it provides for the remaining ones a high quality approximation.

关键词： Discrete tomography reconstruction algorithm color problem

来源：评论

学校读者我要写书评

暂无评论

FLUORESCENCE-ENHANCED OPTICAL TOMOGRAPHY WITH A RADIATIVE TRANSFER-BASED MODEL

FLUORESCENCE-ENHANCED OPTICAL TOMOGRAPHY WITH A RADIATIVE TR...

引用

8th IEEE International Symposium on Biomedical Imaging (ISBI) - From Nano to Macro

作者： Lu, Yujie Sevick-Muraca, Eva M. Univ Texas Hlth Sci Ctr Houston Ctr Mol Imaging Brown Fdn Inst Mol Med Houston TX 77030 USA

ISBN: (纸本)9781424441280

Time-dependent measurements of light propagation have been demonstrated to provide more information compared to time-independent, or continuous wave (CW) measurements for image reconstruction, when employing absorption or fluorescence contrast. Time-dependent measurements made in the frequency domain have been experimentally made with good signal-to-noise ratio (SNR) in preclinical and clinical research at modulation frequencies of 100MHz or less. However, measurements of higher modulation frequencies have potential to improve the reconstruction quality, if SNR can be conserved. In addition, the diffusion approximation (DA) has been demonstrated in both time dependent and independent measurements to be inaccurate in small tissue volumes as well as under conditions of high absorption and low scattering. In this paper, we proposed the third-order simplified spherical harmonics approximations (SP3)-based reconstruction algorithm for fluorescence enhanced optical tomography (FEOT) made in the frequency domain for enhanced accuracy at high modulation frequencies. In this algorithm, fully parallel implementation significantly improves the reconstruction speed and makes the large-scale data-based reconstruction possible. With the Monte Carlo-based synthetic data on the digital mouse phantom, the reconstructed results show the advantages of the proposed algorithm compared to DA-based reconstruction method.

关键词： Fluorescence-enhanced optical tomography reconstruction algorithm high frequency information finite element methods parallel computation Monte Carlo methods

来源：评论

学校读者我要写书评

暂无评论

Performance of the CMS Electromagnetic Calorimeter at the LHC

Performance of the CMS Electromagnetic Calorimeter at the LH...

引用

IEEE Nuclear Science Symposium/Medical Imaging Conference (NSS/MIC)/18th International Workshop on Room-Temperature Semiconductor X-Ray and Gamma-Ray Detectors

作者： Della Ricca, Giuseppe Univ Trieste I-34127 Trieste Italy

ISBN: (纸本)9781467301206

The CMS Electromagnetic Calorimeter (ECAL) is a high resolution, fine-grained calorimeter devised to measure photons and electrons at the LHC. Built of lead tungstate crystals, it plays a crucial role in the search for new physics as well as in precision measurements of the Standard Model. A preshower detector composed of sandwiches of lead and silicon strips improves pi(0)/gamma separation in the forward region. The operation and performance of the ECAL during the 2010 run at the LHC, with pp collisions at root s = 7 TeV will be reviewed, and to some extent for the 2011 running as well. Pure samples of electrons and photons from decays of known resonances have been exploited to improve and verify the trigger efficiency, the reconstruction algorithms, the detector calibration and stability, and the particle identification efficiency. A review of these aspects will be given.

关键词： CMS electromagnetic calorimeter ECAL Electromagnetics Energy management Geometry LHC Large Hadron Collider Magnetic separation Photonics Silicon calibration compact muon solenoid detector calibration detector stability electrons fine-grained calorimeter lead strips lead tungstate crystals particle calorimetry particle identification efficiency photons position sensitive particle detectors preshower detector proton+proton collision reconstruction algorithm shower counters silicon strips solid scintillation detectors standard model trigger efficiency

来源：评论

学校读者我要写书评

暂无评论

Enhancing the performance of upper limb gesture reconstruction through sensory fusion

Enhancing the performance of upper limb gesture reconstructi...

引用

Annual International Conference of the IEEE Engineering in Medicine and Biology Society

作者： Federico Lorussi Alessandro Tognetti Nicola Carbonaro Gaetano Anania Danilo De Rossi Interdepartmental Research Center "E.Piaggio"

ISBN: (纸本)9781424441211

A novel method devoted to the reconstruction of the joint angles in a kinematic chain is described. The reconstruction algorithm is based on the fusion of the information deriving from inertial sensors (accelerometers) and conductive elastomer strain sensors. Accelerometers provide a reliable reconstruction when they are employed as inclinometers in quasi-static conditions. They suffer from artifacts when they are used to detect fast movements or when interactions with the environment occur. The knowledge of the frequency components of the movement to be detected permits removal of these artifacts. Conversely, conductive elastomer sensors have a complex dynamic response, but they can easily provide the frequency content of the movement to be detected. A filtering strategy of the inertial sensor signals based on the elastomer sensor response provides a reliable reconstruction of joint variables during the movement.

关键词： reconstruction algorithm Frequency spectra elastic bodies INCLINOMETER Fusion reactions Kinematic chain inertia sensor Reconstructive Surgical Procedures Gestures accelerometers Upper Extremity Fusion, biological reconstructions Artifacts

来源：评论

学校读者我要写书评

暂无评论

A joint acquisition-reconstruction paradigm for correcting inhomogeneity artifacts in MR echo planar imaging

A joint acquisition-reconstruction paradigm for correcting i...

引用

Annual International Conference of the IEEE Engineering in Medicine and Biology Society

作者： Joseph C. Dagher Francois G. Meyer Institute of Cognitive Science University of Colorado Department of Electrical Engineering University of Colorado

ISBN: (纸本)9781424441211

One of the main sources of signal degradation in rapid MR acquisitions, such as Echo Planar Imaging (EPI), is magnetic field variations caused by field inhomogeneities and susceptibility gradients. If unaccounted for during the reconstruction process, this spatially-varying field can cause severe image artifacts. In this paper, we show that correcting for the resulting degradations can be formulated as a blind image deconvolution problem. We propose a novel joint acquisition-processing paradigm to solve this problem. We describe a practical implementation of this paradigm using a multi-image acquisition strategy and a corresponding joint estimation-reconstruction algorithm. The estimation step computes the spatial distribution of the field maps, while the reconstruction step yields a Minimum Mean Squared Error (MMSE) estimate of the imaged slice. Our simulations show that this proposed joint acquisition-reconstruction method is robust and efficient, offering factors of improvement in the quality of the reconstructed image as compared to other traditional methods.

关键词： Echo-Planar Imaging signal attenuation Inhomogeneities Mean square error Artifacts reconstruction algorithm Quality Improvement

来源：评论

学校读者我要写书评

暂无评论

Optimal Analysis Method for Dynamic Contrast-Enhanced Diffuse Optical Tomography

引用

INTERNATIONAL JOURNAL OF BIOMEDICAL IMAGING 2011年第unknown期2011卷 426503-426515页

作者： Ghijsen, Michael Lin, Yuting Hsing, Mitchell Nalcioglu, Orhan Gulsen, Gultekin Univ Calif Irvine John Tu & Thomas Yuen Ctr Funct Onco Imaging Dept Radiol Sci Irvine CA 92697 USA Pusan Natl Univ Dept Cogno Mech Engn Pusan 609735 South Korea

Diffuse Optical Tomography (DOT) is an optical imaging modality that has various clinical applications. However, the spatial resolution and quantitative accuracy of DOT is poor due to strong photon scatting in biological tissue. Structural a priori information from another high spatial resolution imaging modality such as Magnetic Resonance Imaging (MRI) has been demonstrated to significantly improve DOT accuracy. In addition, a contrast agent can be used to obtain differential absorption images of the lesion by using dynamic contrast enhanced DOT (DCE-DOT). This produces a relative absorption map that consists of subtracting a reconstructed baseline image from reconstructed images in which optical contrast is included. In this study, we investigated and compared different reconstruction methods and analysis approaches for regular endogenous DOT and DCE-DOT with and without MR anatomical a priori information for arbitrarily-shaped objects. Our phantom and animal studies have shown that superior image quality and higher accuracy can be achieved using DCE-DOT together with MR structural a priori information. Hence, implementation of a combined MRI-DOT system to image ICG enhancement can potentially be a promising tool for breast cancer imaging.

关键词： Optical Tomography Image quality Breast Cancer US Department of Transportation reconstruction algorithm

来源：评论

学校读者我要写书评

暂无评论

Through-The-Wall Tomographic Imaging Using Chirp Signals

Through-The-Wall Tomographic Imaging Using Chirp Signals

引用

2011 IEEE International Symposium on Antennas and Propagation(APSURSI 2011)

作者： Ling Huang Yilong Lu School of Electrical and Electronic Engineering Nanyang Technological University Singapore

ISBN: (纸本)9781424495627;9781424495634

This paper presents a feasibility study of using chirp signal for through-the-wall radar imaging and indoor positioning applications. Chirp signal enables frequency diversity while multistatic geometry of tomographic imaging enables space diversity. Pulse compression of chirp aims for range compression of received signals. Beamforming reconstruction algorithm is then applied on compressed signals to produce the final image. In the computer simulation experiments, we have considered using chirp signal and pulsed sine signal as transmitting signals for point targets imaging with building walls in different situations. This study draws a conclusion that using chirp signals, high-quality imaging and positioning results can be obtained.

关键词： tomographic imaging chirp signal through-the-wall imaging CHIRP SIGNALS Chirp modulation Tomography sinusoidal signal compressed signal simulation test Buildings-Walls Frequency diversity received signal reconstruction algorithm

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：