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Three-dimensional image simulation of primary diaphragmatic hemangioma: A case report
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作者 Pei-Yi Chu Kuan-Hsun Lin +2 位作者 Hao-Lun Kao Yi-Jen Peng Tsai-Wang Huang 《World Journal of Clinical Cases》 SCIE 2019年第24期4307-4313,共7页
BACKGROUND Fewer than 200 cases of diaphragmatic tumors have been reported in the past century. Diaphragmatic hemangiomas are extremely rare. Only nine cases have been reported in English literature to date. We report... BACKGROUND Fewer than 200 cases of diaphragmatic tumors have been reported in the past century. Diaphragmatic hemangiomas are extremely rare. Only nine cases have been reported in English literature to date. We report a case of cavernous hemangioma arising from the diaphragm. Pre-operative three-dimensional(3D)simulation and minimal invasive thoracoscopic excision were performed successfully, and we describe the radiologic findings and the surgical procedure in the following article.CASE SUMMARY A 40-year-old man was referred for further examination of a mass over the right basal lung without specific symptoms. Contrast-enhanced computed tomography revealed a poorly-enhanced lesion in the right basal lung, abutting to the diaphragm, measuring 3.1 cm × 1.5 cm in size. The mediastinum showed a clear appearance without evidence of abnormal mass or lymphadenopathy. A preoperative 3D image was reconstructed, which revealed a diaphragmatic lesion. Video-assisted thoracic surgery was performed, and a red papillary tumor was found, originating from the right diaphragm. The tumor was resected, and the pathological diagnosis was cavernous hemangioma.CONCLUSION In this rare case of diaphragmatic hemangioma, 3D image simulation was helpful for the preoperative evaluation and surgical decision making. 展开更多
关键词 Diaphragmatic tumor HEMANGIOMA Case report three-dimensional image simulation Video-assisted thoracic surgery THORACOSCOPY
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Research on Clothing Simulation Design Based on Three-Dimensional Image Analysis 被引量:1
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作者 Wenyao Zhu Xue Li Young-Mi Shon 《Computers, Materials & Continua》 SCIE EI 2020年第10期945-962,共18页
Traditional clothing design models based on adaptive meshes cannot reflect.To solve this problem,a clothing simulation design model based on 3D image analysis technology is established.The model uses feature extractio... Traditional clothing design models based on adaptive meshes cannot reflect.To solve this problem,a clothing simulation design model based on 3D image analysis technology is established.The model uses feature extraction and description of image evaluation parameters,and establishes the mapping relationship between image features and simulation results by using the optimal parameter values,thereby obtaining a three-dimensional image simulation analysis environment.On the basis of this model,by obtaining the response results of clothing collision detection and the results of local adaptive processing of clothing meshes,the cutting form and actual cutting effect of clothing are determined to construct a design model.The simulation results show that compared with traditional clothing design models,clothing simulation design based on 3D image analysis technology has a better effect,with the definition of fabric folds increasing by 40%.More striking contrast between light and dark,the resolution increasing by 30%,and clothing details getting a more real manifestation. 展开更多
关键词 3D image analysis clothing simulation feature extraction optimal solution mapping relationship collision detection grid layout cutting effect
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The Three-dimensional Images and Intracellular Calcium Analysis of Weigela Floridacv and Lonicera Japonica Thunb Pollen 被引量:2
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作者 Dongwu Liu Zhiwei Chen +2 位作者 Xue Wang Hongzhi Xu Lina Wang 《Nano Biomedicine & Engineering》 2009年第1期57-60,共4页
Confocal microscope,which is a major advance upon normal light microscope,has been used in a number of scientific fields.Moreover,the three-dimensional images of specimens can be reconstructed with confocal microscope... Confocal microscope,which is a major advance upon normal light microscope,has been used in a number of scientific fields.Moreover,the three-dimensional images of specimens can be reconstructed with confocal microscope.It is ideal to analyze the three dimensional specimens for the non-destructive,non-invasive nature of the confocal microscope.In the present studies,a series of Weigela floridacv and Lonicera japonica thunb pollen optical sections were acquired with confocal microscope.Then the three-dimensional images of the pollen were reconstructed with the software of confocal microscope.In addition,intracellular calcium in the pollens was detected with the probe Fluo-3 AM,and the distribution of calcium in the pollens was analyzed with confocal microscope.Our results indicate that it is a very easy job to analyze the three-dimensional digital images of the pollen and intracellular calcium in the pollens with confocal microscope and the probes Acridine orange(AO)and Fluo-3 AM. 展开更多
关键词 Confocal microscope POLLEN three-dimensional image RECONSTRUCTION CALCIUM
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Training image analysis for three-dimensional reconstruction of porous media
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作者 滕奇志 杨丹 +2 位作者 徐智 李征骥 何小海 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期415-421,共7页
In order to obtain a better sandstone three-dimensional (3D) reconstruction result which is more similar to the original sample, an algorithm based on stationarity for a two-dimensional (2D) training image is prop... In order to obtain a better sandstone three-dimensional (3D) reconstruction result which is more similar to the original sample, an algorithm based on stationarity for a two-dimensional (2D) training image is proposed. The second-order statistics based on texture features are analyzed to evaluate the scale stationarity of the training image. The multiple-point statistics of the training image are applied to obtain the multiple-point statistics stationarity estimation by the multi-point density function. The results show that the reconstructed 3D structures are closer to reality when the training image has better scale stationarity and multiple-point statistics stationarity by the indications of local percolation probability and two-point probability. Moreover, training images with higher multiple-point statistics stationarity and lower scale stationarity are likely to obtain closer results to the real 3D structure, and vice versa. Thus, stationarity analysis of the training image has far-reaching significance in choosing a better 2D thin section image for the 3D reconstruction of porous media. Especially, high-order statistics perform better than low-order statistics. 展开更多
关键词 three-dimensional reconstruction training image stationarity porous media multiple-point statistics
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Revolutionizing hepatobiliary surgery:Impact of three-dimensional imaging and virtual surgical planning on precision,complications,and patient outcomes
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作者 Himanshu Agrawal Himanshu Tanwar Nikhil Gupta 《Artificial Intelligence in Gastroenterology》 2025年第1期39-51,共13页
BACKGROUND Hepatobiliary surgery is complex and requires a thorough understanding of the liver’s anatomy,biliary system,and vasculature.Traditional imaging methods such as computed tomography(CT)and magnetic resonanc... BACKGROUND Hepatobiliary surgery is complex and requires a thorough understanding of the liver’s anatomy,biliary system,and vasculature.Traditional imaging methods such as computed tomography(CT)and magnetic resonance imaging(MRI),although helpful,fail to provide three-dimensional(3D)relationships of these structures,which are critical for planning and executing complicated surgeries.AIM To explore the use of 3D imaging and virtual surgical planning(VSP)technologies to improve surgical accuracy,reduce complications,and enhance patient recovery in hepatobiliary surgeries.METHODS A comprehensive review of studies published between 2017 and 2024 was conducted through PubMed,Scopus,Google Scholar,and Web of Science.Studies selected focused on 3D imaging and VSP applications in hepatobiliary surgery,assessing surgical precision,complications,and patient outcomes.Thirty studies,including randomized controlled trials,cohort studies,and case reports,were included in the final analysis.RESULTS Various 3D imaging modalities,including multidetector CT,MRI,and 3D rotational angiography,provide high-resolution views of the liver’s vascular and biliary anatomy.VSP allows surgeons to simulate complex surgeries,improving preoperative planning and reducing complications like bleeding and bile leaks.Several studies have demonstrated improved surgical precision,reduced complications,and faster recovery times when 3D imaging and VSP were used in complex surgeries.CONCLUSION 3D imaging and VSP technologies significantly enhance the accuracy and outcomes of hepatobiliary surgeries by providing individualized preoperative planning.While promising,further research,particularly randomized controlled trials,is needed to standardize protocols and evaluate long-term efficacy. 展开更多
关键词 three-dimensional imaging Virtual surgical planning Hepatobiliary surgery Surgical precision Preoperative planning
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Future directions of image-guided thermal ablation in colorectal cancer lung oligometastases
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作者 Yu-Yin Wang Cui-Ping Zhang +3 位作者 Qing-Biao Zhang Xing-Yan Le Jun-Bang Feng Chuan-Ming Li 《World Journal of Gastroenterology》 2026年第2期162-166,共5页
Colorectal cancer(CRC)with lung oligometastases,particularly in the presence of extrapulmonary disease,poses considerable therapeutic challenges in clinical practice.We have carefully studied the multicenter study by ... Colorectal cancer(CRC)with lung oligometastases,particularly in the presence of extrapulmonary disease,poses considerable therapeutic challenges in clinical practice.We have carefully studied the multicenter study by Hu et al,which evaluated the survival outcomes of patients with metastatic CRC who received image-guided thermal ablation(IGTA).These findings provide valuable clinical evidence supporting IGTA as a feasible,minimally invasive approach and underscore the prognostic significance of metastatic distribution.However,the study by Hu et al has several limitations,including that not all pulmonary lesions were pathologically confirmed,postoperative follow-up mainly relied on dynamic contrast-enhanced computed tomography,no comparative analysis was performed with other local treatments,and the impact of other imaging features on efficacy and prognosis was not evaluated.Future studies should include complete pathological confirmation,integrate functional imaging and radiomics,and use prospective multicenter collaboration to optimize patient selection standards for IGTA treatment,strengthen its clinical evidence base,and ultimately promote individualized decision-making for patients with metastatic CRC. 展开更多
关键词 Colorectal cancer Lung oligometastases Extrapulmonary metastases imageguided thermal ablation Dynamic contrast-enhanced computed tomography Functional imaging
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Study on Estimation Method of Rock Mass Discontinuity Shear Strength Based on Three-Dimensional Laser Scanning and Image Technique 被引量:22
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作者 唐辉明 葛云峰 +3 位作者 王亮清 苑谊 黄磊 孙淼军 《Journal of Earth Science》 SCIE CAS CSCD 2012年第6期908-913,共6页
The estimation of shear strength of rock mass discontinuity is always a focal, but difficult, problem in the field of geotechnical engineering. Considering the disadvantages and limitation of exist- ing estimation met... The estimation of shear strength of rock mass discontinuity is always a focal, but difficult, problem in the field of geotechnical engineering. Considering the disadvantages and limitation of exist- ing estimation methods, a new approach based on the shadow area percentage (SAP) that can be used to quantify surface roughness is proposed in this article. Firstly, by the help of laser scanning technique, the three-dimensional model of the surface of rock discontinuity was established. Secondly, a light source was simulated, and there would be some shadows produced on the model surface. Thirdly, to obtain the value of SAP of each specimen, the shadow detection technique was introduced for use. Fourthly, compared with the result from direct shear testing and based on statistics, an empirical for- mula was found among SAP, normal stress, and shear strength. Data of Yujian (~ River were used as an example, and the following conclusions have been made. (1) In the case of equal normal stress, the peak shear stress is positively proportional to the SAP. (2) The formula for estimating was derived, and the predictions of peak-shear strength made with this equation well agreed with the experimental re- suits obtained in laboratory tests. 展开更多
关键词 rock mechanics rock mass discontinuity shear strength estimation method three-dimensional laser scanning technique image recognition technique.
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Three-dimensional positions of scattering centers reconstruction from multiple SAR images based on radargrammetry 被引量:3
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作者 钟金荣 文贡坚 +1 位作者 回丙伟 李德仁 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1776-1789,共14页
A method and procedure is presented to reconstruct three-dimensional(3D) positions of scattering centers from multiple synthetic aperture radar(SAR) images. Firstly, two-dimensional(2D) attribute scattering centers of... A method and procedure is presented to reconstruct three-dimensional(3D) positions of scattering centers from multiple synthetic aperture radar(SAR) images. Firstly, two-dimensional(2D) attribute scattering centers of targets are extracted from 2D SAR images. Secondly, similarity measure is developed based on 2D attributed scatter centers' location, type, and radargrammetry principle between multiple SAR images. By this similarity, we can associate 2D scatter centers and then obtain candidate 3D scattering centers. Thirdly, these candidate scattering centers are clustered in 3D space to reconstruct final 3D positions. Compared with presented methods, the proposed method has a capability of describing distributed scattering center, reduces false and missing 3D scattering centers, and has fewer restrictionson modeling data. Finally, results of experiments have demonstrated the effectiveness of the proposed method. 展开更多
关键词 multiple synthetic aperture radar(SAR) images three-dimensional scattering center position reconstruction radargrammetry
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Specimen aspect ratio and progressive field strain development of sandstone under uniaxial compression by three-dimensional digital image correlation 被引量:15
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作者 H. Munoz A. Taheri 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第4期599-610,共12页
The complete stress-strain characteristics of sandstone specimens were investigated in a series of quasistatic monotonic uniaxial compression tests.Strain patterns development during pre-and post-peak behaviours in sp... The complete stress-strain characteristics of sandstone specimens were investigated in a series of quasistatic monotonic uniaxial compression tests.Strain patterns development during pre-and post-peak behaviours in specimens with different aspect ratios was also examined.Peak stress,post-peak portion of stress-strain,brittleness,characteristics of progressive localisation and field strain patterns development were affected at different extents by specimen aspect ratio.Strain patterns of the rocks were obtained by applying three-dimensional(3D) digital image correlation(DIC) technique.Unlike conventional strain measurement using strain gauges attached to specimen,3D DIC allowed not only measuring large strains,but more importantly,mapping the development of field strain throughout the compression test,i.e.in pre-and post-peak regimes.Field strain development in the surface of rock specimen suggests that strain starts localising progressively and develops at a lower rate in pre-peak regime.However,in post-peak regime,strains increase at different rates as local deformations take place at different extents in the vicinity and outside the localised zone.The extent of localised strains together with the rate of strain localisation is associated with the increase in rate of strength degradation.Strain localisation and local inelastic unloading outside the localised zone both feature post-peak regime. 展开更多
关键词 Uniaxial compression test Aspect ratio Strain patterns Digital image correlation(DIC)
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An image encryption scheme based on three-dimensional Brownian motion and chaotic system 被引量:6
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作者 Xiu-Li Chai Zhi-Hua Gan +2 位作者 Ke Yuan l Yang Lu Yi-Ran Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期99-113,共15页
At present, many chaos-based image encryption algorithms have proved to be unsafe, few encryption schemes permute the plain images as three-dimensional(3D) bit matrices, and thus bits cannot move to any position, th... At present, many chaos-based image encryption algorithms have proved to be unsafe, few encryption schemes permute the plain images as three-dimensional(3D) bit matrices, and thus bits cannot move to any position, the movement range of bits are limited, and based on them, in this paper we present a novel image encryption algorithm based on 3D Brownian motion and chaotic systems. The architecture of confusion and diffusion is adopted. Firstly, the plain image is converted into a 3D bit matrix and split into sub blocks. Secondly, block confusion based on 3D Brownian motion(BCB3DBM)is proposed to permute the position of the bits within the sub blocks, and the direction of particle movement is generated by logistic-tent system(LTS). Furthermore, block confusion based on position sequence group(BCBPSG) is introduced, a four-order memristive chaotic system is utilized to give random chaotic sequences, and the chaotic sequences are sorted and a position sequence group is chosen based on the plain image, then the sub blocks are confused. The proposed confusion strategy can change the positions of the bits and modify their weights, and effectively improve the statistical performance of the algorithm. Finally, a pixel level confusion is employed to enhance the encryption effect. The initial values and parameters of chaotic systems are produced by the SHA 256 hash function of the plain image. Simulation results and security analyses illustrate that our algorithm has excellent encryption performance in terms of security and speed. 展开更多
关键词 image encryption logistic-tent system(LTS) memristive chaotic system three-dimensional(3D) Brownian motion
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Three-Dimensional Model Reconstruction of Nonwovens from Multi-Focus Images 被引量:2
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作者 DONG Gaige WANG Rongwu +1 位作者 LI Chengzu YOU Xiangyin 《Journal of Donghua University(English Edition)》 CAS 2022年第3期185-192,共8页
The three-dimensional(3D)model is of great significance to analyze the performance of nonwovens.However,the existing modelling methods could not reconstruct the 3D structure of nonwovens at low cost.A new method based... The three-dimensional(3D)model is of great significance to analyze the performance of nonwovens.However,the existing modelling methods could not reconstruct the 3D structure of nonwovens at low cost.A new method based on deep learning was proposed to reconstruct 3D models of nonwovens from multi-focus images.A convolutional neural network was trained to extract clear fibers from sequence images.Image processing algorithms were used to obtain the radius,the central axis,and depth information of fibers from the extraction results.Based on this information,3D models were built in 3D space.Furthermore,self-developed algorithms optimized the central axis and depth of fibers,which made fibers more realistic and continuous.The method with lower cost could reconstruct 3D models of nonwovens conveniently. 展开更多
关键词 three-dimensional(3D)model reconstruction deep learning MICROSCOPY NONWOVEN image processing
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An Iterative Algorithm for Angle-limited Three-dimensional Image Reconstruction 被引量:2
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作者 Gang-rong Qu Yong-sheng Lan Ming Jiang 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2008年第1期157-166,共10页
We establish an improved GP iterative algorithm for the extrapolation of band-limited function to fully 3-dimensional image reconstruction by the convolution-backprojection algorithm. Numerical experiments demonstrate... We establish an improved GP iterative algorithm for the extrapolation of band-limited function to fully 3-dimensional image reconstruction by the convolution-backprojection algorithm. Numerical experiments demonstrate that the image resolving power of IGP algorithm is better than that of the original GP algorithm for noisy data. 展开更多
关键词 Fully 3-dimensional image reconstruction convolution-back projection algorithm angle-limited image reconstruction
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Segmentation of retinal fluid based on deep learning:application of three-dimensional fully convolutional neural networks in optical coherence tomography images 被引量:4
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作者 Meng-Xiao Li Su-Qin Yu +4 位作者 Wei Zhang Hao Zhou Xun Xu Tian-Wei Qian Yong-Jing Wan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第6期1012-1020,共9页
AIM: To explore a segmentation algorithm based on deep learning to achieve accurate diagnosis and treatment of patients with retinal fluid.METHODS: A two-dimensional(2D) fully convolutional network for retinal segment... AIM: To explore a segmentation algorithm based on deep learning to achieve accurate diagnosis and treatment of patients with retinal fluid.METHODS: A two-dimensional(2D) fully convolutional network for retinal segmentation was employed. In order to solve the category imbalance in retinal optical coherence tomography(OCT) images, the network parameters and loss function based on the 2D fully convolutional network were modified. For this network, the correlations of corresponding positions among adjacent images in space are ignored. Thus, we proposed a three-dimensional(3D) fully convolutional network for segmentation in the retinal OCT images.RESULTS: The algorithm was evaluated according to segmentation accuracy, Kappa coefficient, and F1 score. For the 3D fully convolutional network proposed in this paper, the overall segmentation accuracy rate is 99.56%, Kappa coefficient is 98.47%, and F1 score of retinal fluid is 95.50%. CONCLUSION: The OCT image segmentation algorithm based on deep learning is primarily founded on the 2D convolutional network. The 3D network architecture proposed in this paper reduces the influence of category imbalance, realizes end-to-end segmentation of volume images, and achieves optimal segmentation results. The segmentation maps are practically the same as the manual annotations of doctors, and can provide doctors with more accurate diagnostic data. 展开更多
关键词 optical COHERENCE tomography imageS FLUID segmentation 2D fully convolutional NETWORK 3D fully convolutional NETWORK
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A novel approach:successful management of vasectomy reversal with a three-dimensional digital image microscope system 被引量:3
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作者 Peng Li Er-Lei Zhi +2 位作者 Chen-Cheng Yao Shu-Jie Xia Zheng Li 《Asian Journal of Andrology》 SCIE CAS CSCD 2021年第1期118-119,共2页
Dear Editor,Microsurgical vasovasostomy,most commonly performed for vasectomy reversal,remains the most successful procedure for restoring patency to the vas deferens with the return of sperm to the ejaculate.Although... Dear Editor,Microsurgical vasovasostomy,most commonly performed for vasectomy reversal,remains the most successful procedure for restoring patency to the vas deferens with the return of sperm to the ejaculate.Although the excellent results depend on the surgeons skill and technique,optimal vision and ergonomics are also crucial factors contributing to the achievement of good results during male infertility microsurgery. 展开更多
关键词 RETURN image SYSTEM
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Asymmetric image encryption algorithm based on a new three-dimensional improved logistic chaotic map 被引量:1
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作者 叶国栋 吴惠山 +1 位作者 黄小玲 Syh-Yuan Tan 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期153-163,共11页
Based on some analyses of existing chaotic image encryption frameworks and a new designed three-dimensional improved logistic chaotic map(3D-ILM),an asymmetric image encryption algorithm using public-key Rivest–Shami... Based on some analyses of existing chaotic image encryption frameworks and a new designed three-dimensional improved logistic chaotic map(3D-ILM),an asymmetric image encryption algorithm using public-key Rivest–Shamir–Adleman(RSA)is presented in this paper.In the first stage,a new 3D-ILM is proposed to enhance the chaotic behavior considering analysis of time sequence,Lyapunov exponent,and Shannon entropy.In the second stage,combined with the public key RSA algorithm,a new key acquisition mathematical model(MKA)is constructed to obtain the initial keys for the 3D-ILM.Consequently,the key stream can be produced depending on the plain image for a higher security.Moreover,a novel process model(NPM)for the input of the 3D-ILM is built,which is built to improve the distribution uniformity of the chaotic sequence.In the third stage,to encrypt the plain image,a pre-process by exclusive OR(XOR)operation with a random matrix is applied.Then,the pre-processed image is performed by a permutation for rows,a downward modulo function for adjacent pixels,a permutation for columns,a forward direction XOR addition-modulo diffusion,and a backward direction XOR addition-modulo diffusion to achieve the final cipher image.Moreover,experiments show that the the proposed algorithm has a better performance.Especially,the number of pixels change rate(NPCR)is close to ideal case 99.6094%,with the unified average changing intensity(UACI)close to 33.4634%,and the information entropy(IE)close to 8. 展开更多
关键词 three-dimensional improved logistic chaotic map(3D-ILM) Rivest–Shamir–Adleman(RSA)algorithm image encryption CONFUSION ENTROPY
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Research and Realization of Medical Image Fusion Based on Three-Dimensional Reconstruction 被引量:5
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作者 TAO Ling QIAN Zhi-yu CHEN Chun-xiao 《Chinese Journal of Biomedical Engineering(English Edition)》 2007年第3期117-122,共6页
A new medical image fusion technique is presented.The method is based on three-dimensional reconstruction.After reconstruction,the three-dimensional volume data is normalized by three-dimensional coordinate conversion... A new medical image fusion technique is presented.The method is based on three-dimensional reconstruction.After reconstruction,the three-dimensional volume data is normalized by three-dimensional coordinate conversion in the same way and intercepted through setting up cutting plane including anatomical structure,as a result two images in entire registration on space and geometry are obtained and the images are fused at last.Compared with traditional two-dimensional fusion technique,three-dimensional fusion technique can not only resolve the different problems existed in the two kinds of images,but also avoid the registration error of the two kinds of images when they have different scan and imaging parameter.The research proves this fusion technique is more exact and has no registration,so it is more adapt to arbitrary medical image fusion with different equipments. 展开更多
关键词 medical image volume data three-dimensional reconstruction image cutting image fusion
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Using restored two-dimensional X-ray images to reconstruct the three-dimensional magnetopause 被引量:2
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作者 RongCong Wang JiaQi Wang +3 位作者 DaLin Li TianRan Sun XiaoDong Peng YiHong Guo 《Earth and Planetary Physics》 EI CSCD 2024年第1期133-154,共22页
Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space physics.The Soft X-ray Imager(SXI)carried by the Solar wind Magnetosph... Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space physics.The Soft X-ray Imager(SXI)carried by the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)aims to capture two-dimensional(2-D)images of the Earth’s magnetosheath by using soft X-ray imaging.However,the observed 2-D images are affected by many noise factors,destroying the contained information,which is not conducive to the subsequent reconstruction of the three-dimensional(3-D)structure of the magnetopause.The analysis of SXI-simulated observation images shows that such damage cannot be evaluated with traditional restoration models.This makes it difficult to establish the mapping relationship between SXIsimulated observation images and target images by using mathematical models.We propose an image restoration algorithm for SXIsimulated observation images that can recover large-scale structure information on the magnetosphere.The idea is to train a patch estimator by selecting noise–clean patch pairs with the same distribution through the Classification–Expectation Maximization algorithm to achieve the restoration estimation of the SXI-simulated observation image,whose mapping relationship with the target image is established by the patch estimator.The Classification–Expectation Maximization algorithm is used to select multiple patch clusters with the same distribution and then train different patch estimators so as to improve the accuracy of the estimator.Experimental results showed that our image restoration algorithm is superior to other classical image restoration algorithms in the SXI-simulated observation image restoration task,according to the peak signal-to-noise ratio and structural similarity.The restoration results of SXI-simulated observation images are used in the tangent fitting approach and the computed tomography approach toward magnetospheric reconstruction techniques,significantly improving the reconstruction results.Hence,the proposed technology may be feasible for processing SXI-simulated observation images. 展开更多
关键词 Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) soft X-ray imager MAGNETOPAUSE image restoration
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Three-dimensional image authentication using binarized images in double random phase integral imaging 被引量:2
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作者 Weitao Song Qijia Cheng +3 位作者 Yue Liu Yuanjin Zheng Zhiping Lin Yongtian Wang 《Chinese Optics Letters》 SCIE EI CAS CSCD 2019年第5期21-25,共5页
We proposed a three-dimensional (3D) image authentication method using binarized phase images in double random phase integral imaging (Ini). Two-dimensional (2D) element images obtained from Ini are encoded using a do... We proposed a three-dimensional (3D) image authentication method using binarized phase images in double random phase integral imaging (Ini). Two-dimensional (2D) element images obtained from Ini are encoded using a double random phase encryption (DRPE) algorithm. Only part of the phase information is used in the proposed method rather than using all of the amplitude and phase information, which can make the final data sparse and beneficial to data compression, storage, and transmission. Experimental results verified the method and successfully proved the developed 3D authentication process using a nonlinear cross correlation method. 展开更多
关键词 three-dimensional(3D) Two-dimensional(2D) DOUBLE RANDOM phase encryption(DRPE)
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Hierarchical MPS-Based Three-Dimensional Geological Structure Reconstruction with Two-Dimensional Image(s) 被引量:3
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作者 Weisheng Hou Hengguang Liu +2 位作者 Tiancheng Zheng Wenjie Shen Fan Xiao 《Journal of Earth Science》 SCIE CAS CSCD 2021年第2期455-467,共13页
Multiple-point statistics(MPS)is a useful approach to reconstruct three-dimensional models in the macroscopic or microscopic field.Extracting spatial features for three-dimensional reconstruction from two-dimensional ... Multiple-point statistics(MPS)is a useful approach to reconstruct three-dimensional models in the macroscopic or microscopic field.Extracting spatial features for three-dimensional reconstruction from two-dimensional training images(TIs),and characterizing non-stationary features with directional ductility are two key issues in MPS simulation.This study presents a step-wise MPS-based three-dimensional structures reconstruction algorithm with the sequential process and hierarchical strategy based on two-dimensional images.An extension method is proposed to construct three-dimensional TIs.With a sequential simulation process,an initial guess at the coarsest scale is simulated,in which hierarchical strategy is used according to the characteristics of TIs.To obtain a more refined realization,an expectation-maximization like iterative process with global optimization is implemented.A concrete example of chondrite micro-structure simulation,in which one scanning electron microscopy(SEM)image of the Heyetang meteorite is used as TI,shows that the presented algorithm can simulate complex non-stationary structures. 展开更多
关键词 multiple-point statistics hierarchical strategy CHONDRITE two-dimensional image(s)
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