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Experimental particle's shapes reconstructions from their interferometric images using the error-reduction algorithm

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OPTICS COMMUNICATIONS 2021年 498卷 127229-127229页

作者： Delestre, Barbara Abad, Alexis Talbi, Mohamed Fromager, Michael Brunel, Marc Univ Rouen Normandie CNRS UMR 6614 CORIA Ave UnivBP 12 F-76801 St Etienne Du Rouvray France Univ Caen CNRS UMR 6252 CIMAPCEAEnsicaen 6 Bd Marechal Juin F-14050 Caen France

The error-reduction algorithm is tested to reconstruct the exact 2D-shape of irregular rough particles from their experimental interferometric images. The particles tested are "programmable"particles generated with a digital micromirror device. The method is first applied to centrosymmetric particles, and then to non-centrosymmetric particles where the twin image problem brings additional difficulty.

关键词： Interferometric particle imaging Speckle error reduction algorithm

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Missing Texture Reconstruction Method Based on error reduction algorithm Using Fourier Transform Magnitude Estimation Scheme

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2013年第3期22卷 1252-1257页

作者： Ogawa, Takahiro Haseyama, Miki Hokkaido Univ Grad Sch Informat Sci & Technol Sapporo Hokkaido 0600814 Japan

A missing texture reconstruction method based on an error reduction (ER) algorithm, including a novel estimation scheme of Fourier transform magnitudes is presented in this brief. In our method, Fourier transform magnitude is estimated for a target patch including missing areas, and the missing intensities are estimated by retrieving its phase based on the ER algorithm. Specifically, by monitoring errors converged in the ER algorithm, known patches whose Fourier transform magnitudes are similar to that of the target patch are selected from the target image. In the second approach, the Fourier transform magnitude of the target patch is estimated from those of the selected known patches and their corresponding errors. Consequently, by using the ER algorithm, we can estimate both the Fourier transform magnitudes and phases to reconstruct the missing areas.

关键词： error reduction algorithm Fourier transform magnitude estimation image reconstruction phase retrieval texture analysis

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Compressive image encryption with customized key based on phase retrieval

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OPTICAL ENGINEERING 2017年第2期56卷 023103-023103页

作者： Di, Hong Zhang, Xin Univ Int Relat Dept Informat Sci & Technol Beijing Peoples R China Chinese Acad Sci Brainnetome Ctr Inst Automat Beijing Peoples R China Chinese Acad Sci Natl Lab Pattern Recognit Inst Automat Beijing Peoples R China

Recently, image encryption has been significantly improved by methods originating from optics. Phase retrieval is one method potentially applicable to image encryption. It is the process of algorithmically finding solutions to a phase loss problem due to light detectors only capturing the intensity of lights. Because the phase retrieval can constrain information to the phase with a specified condition, we propose using it to encrypt an image and compress it as phase information simultaneously. Moreover, the encryption will involve a customized key known only to authorized users. The encryption strategy provides dual protection of the encrypted image from unauthorized access. Experiments have been conducted to demonstrate the performance of the encryption method. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)

关键词： image encryption phase retrieval error reduction algorithm image processing

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A TEXTON FOR FAST AND FLEXIBLE GAUSSIAN TEXTURE SYNTHESIS 22

A TEXTON FOR FAST AND FLEXIBLE GAUSSIAN TEXTURE SYNTHESIS

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22nd European Signal Processing Conference (EUSIPCO)

作者： Galerne, Bruno Leclaire, Arthur Moisan, Lionel Univ Paris 05 MAP5 CNRS UMR 8145 Paris France

ISBN: (纸本)9780992862619

Gaussian textures can be easily simulated by convolving an image sample with a white noise. However, this procedure is not very flexible (it does not allow for non-uniform grids in particular), and becomes computationally heavy for very large domains. We here propose an algorithm that summarizes a texture sample into a synthesis-oriented texton, that is, a small image for which the discrete spot noise simulation (summed and normalized randomly-shifted copies of the texton) is more efficient than the classical convolution algorithm. Using this synthesis-oriented texture summary, Gaussian textures can be generated on-demand in a faster, simpler, and more flexible way.

关键词： Spot noise texton Gaussian texture texture synthesis error reduction algorithm

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A TEXTON FOR FAST AND FLEXIBLE GAUSSIAN TEXTURE SYNTHESIS

A TEXTON FOR FAST AND FLEXIBLE GAUSSIAN TEXTURE SYNTHESIS

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European Signal Processing Conference

作者： Bruno Galerne Arthur Leclaire Lionel Moisan Universite Paris Descartes

ISBN: (纸本)9781479946037

Gaussian textures can be easily simulated by convolving an image sample with a white noise. However, this procedure is not very flexible (it does not allow for non-uniform grids in particular), and becomes computationally heavy for very large domains. We here propose an algorithm that summarizes a texture sample into a synthesis-oriented texton, that is, a small image for which the discrete spot noise simulation (summed and normalized randomly-shifted copies of the texton) is more efficient than the classical convolution algorithm. Using this synthesis-oriented texture summary, Gaussian texture can be generated on-demand in a faster, simpler, and more flexible way.

关键词： Spot noise Texton Gaussian texture Texture synthesis error reduction algorithm

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MIMO Radar Waveform Design to support Spectrum Sharing

MIMO Radar Waveform Design to support Spectrum Sharing

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IEEE Military Communications Conference

作者： Amuru, SaiDhiraj Buehrer, R. Michael Tandon, Ravi Sodagari, Shabnam Virginia Tech Bradley Dept Elect & Comp Engn Blacksburg VA 24061 USA

ISBN: (纸本)9780769551241

In this paper, we propose an information theoretic waveform design algorithm for multiple-input multiple-output radars to support co-existence with a communication system under additional constraints on interference reduction from the clutter, minimizing the peak-to-average-power ratio and minimizing correlation levels of the radar. Numerical results are presented which show the performance of the proposed waveform design algorithm in terms of mutual information, interference reduction and sidelobe levels of the radar waveform.

关键词： MIMO radar waveform design co-existence spectrum sharing error reduction algorithm

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3D Reconstruction of 2D Crystals 11

3D Reconstruction of 2D Crystals

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49th Annual Association-for-Computing-Machinery (ACM) Southeast Conference (ACMSE)

作者： Zeng, Xiangyan Glover, James Ervin Hughes, Owen Stahlberg, Henning Ft Valley State Univ 1005 State Univ Dr Ft Valley GA 31030 USA Eon Corp Davis CA 95616 USA Univ Basel CH-4058 Basel Switzerland

ISBN: (纸本)9781450306867

High Resolution three-dimensional (3D) reconstruction of several proteins has been achieved from two-dimensional (2D) crystals by electron crystallography structure determination. However, for badly ordered 2D crystals, especially non-flat crystals, Fourierfiltering based methods fail, while single particle processing approaches can produce reconstructions of superior resolution by aligning particles in 3D space. We have investigated a single particle processing approach combined with the crystallographic method to generate images centered on the unit cells of 2D crystal images. The implemented software uses the predictive lattice node tracking in 2dx/ MRC software to extract particles from the microscope images. These particles are then subjected to a local contrast transfer function (CTF) correction. The tilt geometry obtained in the 2dx software is used to initialize the Euler angles, which along with translations are then refined by a single particle processing approach. Finally, iterative transform algorithms, namely the error reduction algorithm and the hybrid input-output algorithm, are applied to retrieve missing information in the previously obtained 3D reconstruction. Compared with conventional single particle processing for randomly oriented particles, the required computational costs are greatly reduced as the 2D crystals restrict the parameter search space. Preliminary results from a 3D reconstruction of the membrane protein GlpF suggest that the iterative transform process improves 3D resolution.

关键词： 3D reconstruction electron crystallography single particle processing error reduction algorithm hybrid input-output algorithm

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Preliminary Studies on Iterative Transform algorithms for 3D Reconstruction of 2D Crystals

Preliminary Studies on Iterative Transform Algorithms for 3D...

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The 2nd International Conference on Software Engineering and Data Mining(IEEE 第二届国际软件工程和数据挖掘学术大会 SEDM 2010)

作者： Xiangyan Zeng Yen-Wei Chen Owen Hughes Henning Stahlberg Department of Mathematics and Computer Science Fort Valley State University Fort Valley GA 31030. U College of Information Science and Engineering Ritsumeikan University Shiga 525-8577Japan Eon Corporation Davis CA 95616USA Center for Cellular Imaging and Nanoanalytics University Basel CH-4058 Basel Switzerland

ISBN: (纸本)9781424473243;9788988678220;9788988678213

In this paper, we apply iterative transform algorithms,namely the error reduction algorithm and the hybrid input-output algorithm, to retrieve missing data in 3D reconstruction from 2D crystal images. 3D protein structures are determined using cryo-electron microscopy (cryo-EM). Extremely strong noise in cryo-EM brings in unreliable artifacts and a limited number of projections leave missing components in 3D Fourier space. We consider all these cases as missing data problems. The iterative transform algorithms aim at improving 3D resolution through applying constraints in Fourier space and real space. In Fourier space, the “true” signal components, which are either physically measured or assumed, are retained while the delusive components are updated iteratively. In real space, the protein has spatial limitation or “finite support” and possesses non-negativity values. Preliminary results of 3D reconstruction of membrane protein GlpF suggest that the iterative transform process improves 3D resolution.

关键词： 3D reconstruction cryo-electron microscopy error reduction algorithm hybrid input-output algorithm

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Mechanical property measurement by indentation techniques

Mechanical property measurement by indentation techniques

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作者： Janakiraman, Balasubramanian Texas A&M University

The mechanical properties of materials are usually evaluated by performing a tensile or hardness test on the sample. Tensile tests are often time consuming, destructive and need specially prepared specimens. On the other hand, there is no direct theoretical correlation between the hardness number and the mechanical properties of a material although phenomenological relationships do exist. The advantages of indentation techniques are that they are non-destructive, quick, and can be applied to small material samples and localized in fashion. Mechanical properties are typically determined from spherical indentation load-depth curves. This process is again a time consuming one and not suitable for situations where a quick assessment is required such as in the sheet metal rolling industry. In the present study, a novel method of measuring mechanical properties of the material by multiple spherical indentations is developed. A series of indentations are made on the substrate with a spherical indenter with different loads. The diameter of the indentation is related to the load applied to determine the mechanical properties of the material, namely the yield strength and the work hardening parameters. To determine the diameter of the indentation quickly, a fiber optic sensing technique is developed. An incident light beam from a semiconductor laser is coupled back into an optical fiber upon reflection from the metal surface. By measuring the diffused light power reflected from the metal surface, the diameter of the indentation is measured. The spherical indentation technique is difficult for real time mechanical property measurement of sheet metal in a processing line. Problems arise as the strip is traveling at 2,000 to 4,000 ft/min (10,000 to 20,000 mm/sec) in the processing line. As a first step in developing a process that could be implemented in a real time processing line, a preliminary study has been conducted for the prediction of yield strength by laser shock proces

关键词： Yield strength Work hardening coefficients spherical indentation error reduction algorithm fiber optics sensing technique Laser shock processing Book Thesis

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Multispectra method for error reduction of the quantized Fourier modulus in the iterative Fourier transform algorithms used for phase retrieval

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OPTICAL ENGINEERING 2004年第3期43卷 713-717页

作者： Yang, SY Takajo, H Kyushu Inst Technol Dept Elect Engn Kitakyushu Fukuoka 8048550 Japan

A multispectra method is proposed for the error reduction of the quantized Fourier modulus in the iterative Fourier transform. algorithms used for phase retrieval. The Fourier modulus is usually obtained by measuring the Fourier intensity with a digital device, thus the quantization error caused in the measurements of Fourier intensity leads to the error of the reconstructed object when iterative Fourier transform algorithms are used. The idea of the multispectra method uses several Fourier intensity distributions for various measuring ranges to generate a Fourier intensity distribution with low-quantization error. The error reduction of Fourier intensity with the multispectra method connects to the improvement of the phase retrieval with the iterative Fourier transform algorithms. Simulations are performed to demonstrate the effect of the multispectra method for phase retrieval with the iterative hybrid input-output algorithm. (C) 2004 Society of Photo-Optical Instrumentation Engineers.

关键词： iterative Fourier transform algorithm phase retrieval Fourier modulus Fourier intensity quantization error reduction algorithm hybrid input-out algorithm

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