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Frontiers of Structural and Civil Engineering 2019年第3期13卷 701-715页

作者： Hamid Taghavi GANJI Mohammad ALEMBAGHERI Mohammad Houshmand KHANEGHAHI Department of Civil and Environmental Engineering Amirkabir University of TechnologyTehranIran Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran Department of Civil Engineering Shahid Beheshti UniversityTehranIran

The seismic performance of gravity dam-reservoir-foundation coupled system is investigated utilizing probabilistic approach.In this research,the uncertainties associated with modeling parameters are incorporated in nonlinear response history simulations to realistically quantify their effects on the seismic performance of the system.The methodology is applied to Pine Flat gravity dam and the foundation is considered to be inhomogeneous assuming a constant spatial geometry but with various rock material properties.The sources of uncertainty are taken into account in the reliability analysis using Latin Hypercube Sampling procedure.The effects of the deconvolution process,number of samples,and foundation inhomogeneity are investigated.

关键词： gravity dams dam-reservoir-foundation interaction seismic reliability inhomogeneous foundation earthquake deconvolution

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切比雪夫加权反卷积波束形成方法研究

Journal of Marine Science and Application 2022年第3期21卷 228-235页

作者：王舒徽卢明洋梅继丹崔文婷 Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001China Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China

This paper studies a deconvolved Chebyshev beamforming(Dcv-Che-BF)method.Compared with other deconvolution beamforming methods,Dcv-Che-BF can preset sidelobe levels according to the actual situation,which can achieve higher resolution performance.However,the performance of Dcv-Che-BF was not necessarily better with a lower preset sidelobe level in the presence of noise.Instead,it was much better when the preset side lobe level matched the signal to noise ratio of the signal.The performance of the Dcv-Che-BF method with different preset sidelobe levels was analyzed using simulation.The Dcv-Che-BF method achieved a lower sidelobe level and better resolution capability when the preset sidelobe level was slightly greater than the noise background level.To validate the feasibility and performance of the proposed method,computer simulations and sea trials were analyzed.The results show that the Dcv-Che-BF method is a robust high-resolution beamforming method that can achieve a narrow mainlobe and low sidelobe.

关键词： Chebyshev weighting deconvolution Beamforming High resolution Robust

Development of cryptotanshinone-loaded pellets for angina chronotherapy:In vitro/in vivo prediction and evaluation

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Asian Journal of Pharmaceutical Sciences 2018年第4期13卷 310-316页

作者： Zhenghua Li Shuangshuang Zhang Hongxiang Yan Jianping Liu Department of Pharmaceutics China Pharmaceutical University

The clinical manifestations of variant angina is unevenly distributed during the 24 h, thusthe in vivo performance of drugs should be tailored according to the angina circadianrhythm. Cryptotanshinone(CTN) is one of the representative bioactive lipid-soluble com-ponents of Danshen which has been commonly used for cardiovascular diseases such asangina pectoris. The aim of this study was to develop a novel CTN sustained-released pel-lets(CTN-SRPs) to precisely synchronize the CTN plasma concentrations with predictedoccurrence of angina pectoris for angina chronotherapy. A deconvolution-based methodwas applied to develop and optimize the CTN-SRPs. The plasma concentration-time curveof CTN immediate-released formulation after oral administration in rats was used as theweight function. The predicted plasma concentration-time curve of CTN-SRPs simulatedaccording to the incidence of variant angina during 24 h was used as the response func-tion. Then the desired drug release profile of CTN-SRPs was calculated based on deconvo-lution using weight function and response function, and subsequently used for guiding theformulation optimization. CTN-SRPs were prepared with the combinations of PVP, polox-amer 127 and EC as matrix using fluidized bed technology. An orthogonal design was em-ployed to obtain the optimal formulation with its release profile similar with the desiredone. Pharmacokinetic studies validated that the actual plasma concentration-time curve ofthese optimized CTN-SRPs was similar with the predicted one. In addition, the percent er-rors(%PE) of CTN plasma concentrations in 8–12 h were less than 10%. In conclusion, thisdeconvolution-based method could be applied to adjust the in vivo performance of drugs forangina chronotherapy.

关键词： Chronotherapy deconvolution Angina pectoris Cryptotanshinone In vitro/in vivo performance Control release

Point spread function estimation from projected speckle illumination

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Light(Science & Applications) 2015年第1期4卷 92-98页

作者： Nizan Meitav Erez N Ribak Shy Shoham Department of Biomedical Engineering Technion-Israel Institute of TechnologyTechnion CityHaifa 32000Israel Department of Physics Technion-Israel Institute of TechnologyTechnion CityHaifa 32000Israel

The resolution of an imaging apparatus is ideally limited by the diffraction properties of the light passing through the system aperture,but in many practical cases,inhomogeneities in the light propagating medium or imperfections in the optics degrade the image resolution.Here we introduce a powerful and practical new approach for estimating the point spread function(PSF)of an imaging system on the basis of PSF Estimation from Projected Speckle Illumination(PEPSI).PEPSI uses the fact that the speckles’phase randomness cancels the effects of the aberrations in the illumination path,thereby providing an objective pattern for measuring the deformation of the imaging path.Using this approach,both wide-field-of-view and local-PSF estimation can be obtained by calibration-free,single-speckle-pattern projection.Finally,we demonstrate the feasibility of using PEPSI estimates for resolution improvement in iterative maximum likelihood deconvolution.

关键词： deconvolution microscopy optical aberrations speckle pattern

Optical imaging of post-embryonic zebrafish using multi orientation raster scan optoacoustic mesoscopy

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Light(Science & Applications) 2016年第1期5卷 336-341页

作者： Murad Omar Johannes Rebling Kai Wicker Tobias Schmitt-Manderbach Mathias Schwarz Jérôme Gateau Hérnan López-Schier Timo Mappes Vasilis Ntziachristos Chair for Biological Imaging Technische Universität MünchenMünchen D-81675Germany Institute for Biological and Medical Imaging Helmholtz Zentrum MünchenNeuherberg D-85764Germany Carl Zeiss AG Corporate Research and TechnologyJena D-07745Germany ESPCI Paris PSL Research UniversityCNRSINSERMInstitut LangevinParis F-75005France Research Unit Sensory Biology and Organogenesis Helmholtz Zentrum MünchenNeuherberg D-85764Germany Carl Zeiss Vision International GmbH Technology&InnovationAalen D-73430Germany

Whole-body optical imaging of post-embryonic stage model organisms is a challenging and long sought-after goal.It requires a combination of high-resolution performance and high-penetration depth.Optoacoustic(photoacoustic)mesoscopy holds great promise,as it penetrates deeper than optical and optoacoustic microscopy while providing high-spatial resolution.However,optoacoustic mesoscopic techniques only offer partial visibility of oriented structures,such as blood vessels,due to a limited angular detection aperture or the use of ultrasound frequencies that yield insufficient resolution.We introduce 3601 multi orientation(multi-projection)raster scan optoacoustic mesoscopy(MORSOM)based on detecting an ultra-wide frequency bandwidth(up to 160 MHz)and weighted deconvolution to synthetically enlarge the angular aperture.We report unprecedented isotropic inplane resolution at the 9–17μm range and improved signal to noise ratio in phantoms and opaque 21-day-old Zebrafish.We find that MORSOM performance defines a new operational specification for optoacoustic mesoscopy of adult organisms,with possible applications in the developmental biology of adulthood and aging.

关键词： deconvolution development mesoscopy multiview optoacoustics photoacoustics

Study of measuring methods on spatial resolution of a GEM imaging detector

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Chinese Physics C 2012年第3期36卷 228-234页

作者：吕新宇樊瑞睿陈元柏欧阳群刘荣光刘鹏祁辉荣张健赵平平赵东旭赵豫斌章红宇盛华义董丽媛 Institute of High Energy Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences State Key Laboratory of Particle Detection and Electronics School of Nuclear Science and Technology Lanzhou University

In this paper, the limitations of the common method measuring intrinsic spatial resolution of the GEM imaging detector are presented. Through theoretical analysis and experimental verification, we have improved the common method to avoid these limitations. Using these improved methods, a more precise measurement of intrinsic spatial resolutions are obtained.

关键词： spatial resolution imaging detector GEM convolution deconvolution

Improved Channel Reciprocity for Secure Communication in Next Generation Wireless Systems

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Computers, Materials & Continua 2021年第5期67卷 2619-2630页

作者： Imtisal Qadeer Muhammad Khurram Ehsan Faculty of Engineering Bahria UniversityLahore CampusLahorePakistan

To secure the wireless connection between devices with low computational power has been a challenging problem due to heterogeneity in operating devices,device to device communication in Internet of Things(IoTs)and 5G wireless systems.Physical layer key generation(PLKG)tackles this secrecy problem by introducing private keys among two connecting devices through wireless medium.In this paper,relative calibration is used as a method to enhance channel reciprocity which in turn increases the performance of the key generation process.Channel reciprocity based key generation is emerged as better PLKG methodology to obtain secure wireless connection in IoTs and 5G systems.Circulant deconvolution is proposed as a promising technique for relative calibration to ensure channel reciprocity in comparison to existing techniques Total Least Square(TLS)and Structured Total Least Square(STLS).The proposed deconvolution technique replicates the performance of the STLS by exploiting the possibility of higher information reuse and its lesser computational complexity leads to less processing time in comparison to the STLS.The presented idea is validated by observing the relation between signalto-noise ratio(SNR)and the correlation coefficient of the corresponding channel measurements between communicating parties.

关键词： Channel measurements physical layer key generation channel reciprocity Internet of things deconvolution

Advantages of cluster analysis for multifunctional and intercrossing brain area distribution Evaluation by functional magnetic resonance imaging

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Neural Regeneration Research 2008年第6期3卷 604-609页

作者： Hongchang Zhai Xudong Xu Shengyong Xiao Department of Psychology Guangzhou University Education College Guangzhou 510006 Guangdong Province China

BACKGROUND： Multiple linear regression, general linear test and calculation of correlation values are commonly used in studies of brain function using functional magnetic resonance imaging （fMRI）. However, there are some limitations in their applications. In non-signal data statistics, cluster analysis functions as a very mature method, but it is not reliable in signal data statistics. OBJECTIVE： To investigate the spatial distribution of complex function in brain areas during motor tasks by cluster analysis, and to compare this with multiple linear regression. DESIGN, TIME AND SETTING： Block design, performed at the MR laboratory of Guangzhou University of Chinese Medicine. PARTICIPANTS： Fifteen right-handed, healthy university students （10 males and 5 females, aged 19-21 years）. METHODS： fMRI was performed while the subjects performed a finger movement task with the right hand. The screen showed a gray hand, with red spots presented in a random order on one of the index, middle, ring and little fingers. The subjects were required to remember the sequence of the red spots on the display. After a delay of 14 seconds, the subjects tapped their fingers according to the order of the red spots, as soon as the red spots turned green. After an interval of 14 seconds, another sequence appeared. Every sequence lasted for 28 seconds, including preparation and execution phases. A total of nine sequences per subject were performed. The data were analyzed using deconvolution and cluster methods, and program ＂cluster＂ was used to statistically analyze the coordinate positions of deconvolution and cluster data. MAIN OUTCOME MEASURES： Brain activation maps by deconvolution and brain function maps by clustering of the maximum peak values; blood oxygenation level dependent curves by deconvolution; coordinates of peak values and activation volumes by the two methods. RESULTS： The deconvolution method could not integrate the brain activation maps during different tasks into one activation picture, which made it difficult to identif

关键词： functional magnetic resonance motion cluster deconvolution

Unfolding analysis of LaBr3:Ce gamma spectrum with a detector response matrix constructing algorithm based on energy resolution calibration

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Nuclear Science and Techniques 2018年第1期29卷 23-31页

作者： Rui Shi Xian-Guo Tuo Huai-Liang Li Yang-Yang Xu Fan-Rong Shi Jian-Bo Yang Yong Luo Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory Southwest University of Science and Technology Mianyang 621010 China Sichuan University of Science and Engineering Zigong 643000 China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

With respect to the gamma spectrum, the energy resolution improves with increase in energy. The counts of full energy peak change with energy, and this approximately complies with the Gaussian distribution. This study mainly examines a method to deconvolve the LaBr_3:Ce gamma spectrum with a detector response matrix constructing algorithm based on energy resolution calibration.In the algorithm, the full width at half maximum(FWHM)of full energy peak was calculated by the cubic spline interpolation algorithm and calibrated by a square root of a quadratic function that changes with the energy. Additionally, the detector response matrix was constructed to deconvolve the gamma spectrum. Furthermore, an improved SNIP algorithm was proposed to eliminate the background. In the experiment, several independent peaks of ^(152)Eu,^(137)Cs, and ^(60)Co sources were detected by a LaBr_3:Ce scintillator that were selected to calibrate the energy resolution. The Boosted Gold algorithm was applied to deconvolve the gamma spectrum. The results showed that the peak position difference between the experiment and the deconvolution was within ± 2 channels and the relative error of peak area was approximately within 0.96–6.74%. Finally, a ^(133) Ba spectrum was deconvolved to verify the efficiency and accuracy of the algorithm in unfolding the overlapped peaks.

关键词： Detector response matrix Energy resolution calibration LaBr3:Ce scintillator SNIP background elimination Boosted Gold deconvolution algorithm