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Evaluating the use of three-dimensional reconstruction visualization technology for precise laparoscopic resection in gastroesophageal junction cancer
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作者 Dan Guo Xiao-Yan Zhu +2 位作者 Shuai Han Yu-Shu Liu Da-Peng Cui 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第5期1311-1319,共9页
BACKGROUND Laparoscopic gastrectomy for esophagogastric junction(EGJ)carcinoma enables the removal of the carcinoma at the junction between the stomach and esophagus while preserving the gastric function,thereby provi... BACKGROUND Laparoscopic gastrectomy for esophagogastric junction(EGJ)carcinoma enables the removal of the carcinoma at the junction between the stomach and esophagus while preserving the gastric function,thereby providing patients with better treatment outcomes and quality of life.Nonetheless,this surgical technique also presents some challenges and limitations.Therefore,three-dimensional reconstruction visualization technology(3D RVT)has been introduced into the procedure,providing doctors with more comprehensive and intuitive anatomical information that helps with surgical planning,navigation,and outcome evaluation.AIM To discuss the application and advantages of 3D RVT in precise laparoscopic resection of EGJ carcinomas.METHODS Data were obtained from the electronic or paper-based medical records at The First Affiliated Hospital of Hebei North University from January 2020 to June 2022.A total of 120 patients diagnosed with EGJ carcinoma were included in the study.Of these,68 underwent laparoscopic resection after computed tomography(CT)-enhanced scanning and were categorized into the 2D group,whereas 52 underwent laparoscopic resection after CT-enhanced scanning and 3D RVT and were categorized into the 3D group.This study had two outcome measures:the deviation between tumor-related factors(such as maximum tumor diameter and infiltration length)in 3D RVT and clinical reality,and surgical outcome indicators(such as operative time,intraoperative blood loss,number of lymph node dissections,R0 resection rate,postoperative hospital stay,postoperative gas discharge time,drainage tube removal time,and related complications)between the 2D and 3D groups.RESULTS Among patients included in the 3D group,27 had a maximum tumor diameter of less than 3 cm,whereas 25 had a diameter of 3 cm or more.In actual surgical observations,24 had a diameter of less than 3 cm,whereas 28 had a diameter of 3 cm or more.The findings were consistent between the two methods(χ^(2)=0.346,P=0.556),with a kappa consistency coefficient of 0.808.With respect to infiltration length,in the 3D group,23 patients had a length of less than 5 cm,whereas 29 had a length of 5 cm or more.In actual surgical observations,20 cases had a length of less than 5 cm,whereas 32 had a length of 5 cm or more.The findings were consistent between the two methods(χ^(2)=0.357,P=0.550),with a kappa consistency coefficient of 0.486.Pearson correlation analysis showed that the maximum tumor diameter and infiltration length measured using 3D RVT were positively correlated with clinical observations during surgery(r=0.814 and 0.490,both P<0.05).The 3D group had a shorter operative time(157.02±8.38 vs 183.16±23.87),less intraoperative blood loss(83.65±14.22 vs 110.94±22.05),and higher number of lymph node dissections(28.98±2.82 vs 23.56±2.77)and R0 resection rate(80.77%vs 61.64%)than the 2D group.Furthermore,the 3D group had shorter hospital stay[8(8,9)vs 13(14,16)],time to gas passage[3(3,4)vs 4(5,5)],and drainage tube removal time[4(4,5)vs 6(6,7)]than the 2D group.The complication rate was lower in the 3D group(11.54%)than in the 2D group(26.47%)(χ^(2)=4.106,P<0.05).CONCLUSION Using 3D RVT,doctors can gain a more comprehensive and intuitive understanding of the anatomy and related lesions of EGJ carcinomas,thus enabling more accurate surgical planning. 展开更多
关键词 Gastroesophageal junction cancer ENDOSCOPY Tumor resection three-dimensional reconstruction visualization Two-dimensional imaging computed tomography
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Computed tomography three-dimensional reconstruction in the diagnosis of bleeding small intestinal polyps:A case report
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作者 Shu-Hui Zhang Ming-Wei Fan +2 位作者 Yan Chen Ying-Bin Hu Cheng-Xia Liu 《World Journal of Clinical Cases》 SCIE 2024年第16期2831-2836,共6页
BACKGROUND Computed tomography(CT)small bowel three-dimensional(3D)reconstruction is a powerful tool for the diagnosis of small bowel disease and can clearly show the intestinal lumen and wall as well as the outside s... BACKGROUND Computed tomography(CT)small bowel three-dimensional(3D)reconstruction is a powerful tool for the diagnosis of small bowel disease and can clearly show the intestinal lumen and wall as well as the outside structure of the wall.The horizontal axis position can show the best adjacent intestinal tube and the lesion between the intestinal tubes,while the coronal position can show the overall view of the small bowel.The ileal end of the localization of the display of excellent,and easy to quantitative measurement of the affected intestinal segments,the sagittal position for the rectum and the pre-sacral lesions show the best,for the discovery of fistulae is also helpful.Sagittal view can show rectal and presacral lesions and is useful for fistula detection.It is suitable for the assessment of inflammatory bowel disease,such as assessment of disease severity and diagnosis and differential diagnosis of the small bowel and mesenteric space-occupying lesions as well as the judgment of small bowel obstruction points.CASE SUMMARY Bleeding caused by small intestinal polyps is often difficult to diagnose in clinical practice.This study reports a 29-year-old male patient who was admitted to the hospital with black stool and abdominal pain for 3 months.Using the combination of CT-3D reconstruction and capsule endoscopy,the condition was diagnosed correctly,and the polyps were removed using single-balloon enteroscopyendoscopic retrograde cholangiopancreatography without postoperative complications.CONCLUSION The role of CT-3D in gastrointestinal diseases was confirmed.CT-3D can assist in the diagnosis and treatment of gastrointestinal diseases in combination with capsule endoscopy and small intestinal microscopy. 展开更多
关键词 Computed tomography three-dimensional reconstruction Capsule endoscopy Single-balloon enteroscopy Gastrointestinal bleeding Case report
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GPU-accelerated three-dimensional reconstruction method of the Compton camera and its application in radionuclide imaging 被引量:1
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作者 Ren-Yao Wu Chang-Ran Geng +6 位作者 Feng Tian Zhi-Yang Yao Chun-Hui Gong Hao-Nan Han Jian-Feng Xu Yong-Shun Xiao Xiao-Bin Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第4期54-68,共15页
A novel and fast three-dimensional reconstruction method for a Compton camera and its performance in radionuclide imaging is proposed and analyzed in this study. The conical surface sampling back-projection method wit... A novel and fast three-dimensional reconstruction method for a Compton camera and its performance in radionuclide imaging is proposed and analyzed in this study. The conical surface sampling back-projection method with scattering angle correction(CSS-BP-SC) can quickly perform the back-projection process of the Compton cone and can be used to precompute the list-mode maximum likelihood expectation maximization(LM-MLEM). A dedicated parallel architecture was designed for the graphics processing unit acceleration of the back-projection and iteration stage of the CSS-BP-SC-based LM-MLEM. The imaging results of the two-point source Monte Carlo(MC) simulation demonstrate that by analyzing the full width at half maximum along the three coordinate axes, the CSS-BP-SC-based LM-MLEM can obtain imaging results comparable to those of the traditional reconstruction algorithm, that is, the simple back-projection-based LM-MLEM. The imaging results of the mouse phantom MC simulation and experiment demonstrate that the reconstruction results obtained by the proposed method sufficiently coincide with the set radioactivity distribution, and the speed increased by more than 664 times compared to the traditional reconstruction algorithm in the mouse phantom experiment. The proposed method will further advance the imaging applications of Compton cameras. 展开更多
关键词 Compton camera three-dimensional reconstruction Radionuclide imaging GPU
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Single exposure passive three-dimensional information reconstruction based on an ordinary imaging system
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作者 窦申成 刘璠 +3 位作者 李虎 姚旭日 刘雪峰 翟光杰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期446-455,共10页
Existing three-dimensional(3D) imaging technologies have issues such as requiring active illumination, multiple exposures, or coding modulation. We propose a passive single 3D imaging method based on an ordinary imagi... Existing three-dimensional(3D) imaging technologies have issues such as requiring active illumination, multiple exposures, or coding modulation. We propose a passive single 3D imaging method based on an ordinary imaging system.Using the point spread function of the imaging system to realize the non-coding measurement on the target, the full-focus images and depth information of the 3D target can be extracted from a single two-dimensional(2D) image through the compressed sensing algorithm. Simulation and experiments show that this approach can complete passive 3D imaging based on an ordinary imaging system without any coding operations. This method can achieve millimeter-level vertical resolution under single exposure conditions and has the potential for real-time dynamic 3D imaging. It improves the efficiency of 3D information detection, reduces the complexity of the imaging system, and may be of considerable value to the field of computer vision and other related applications. 展开更多
关键词 passive three-dimensional imaging single exposure point spread function compressed sensing
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Image processing based three-dimensional model reconstruction for cross-platform numerical simulation
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作者 Yu-cheng Sun Yu-hang Huang +5 位作者 Na Li Xiao Han Ai-long Jiang Jin-wu Kang Ji-wu Wang Hai-liang Yu 《China Foundry》 SCIE CAS CSCD 2023年第2期139-147,共9页
Numerical simulation is the most powerful computational and analysis tool for a large variety of engineering and physical problems.For a complex problem relating to multi-field,multi-process and multi-scale,different ... Numerical simulation is the most powerful computational and analysis tool for a large variety of engineering and physical problems.For a complex problem relating to multi-field,multi-process and multi-scale,different computing tools have to be developed so as to solve particular fields at different scales and for different processes.Therefore,the integration of different types of software is inevitable.However,it is difficult to perform the transfer of the meshes and simulated results among software packages because of the lack of shared data formats or encrypted data formats.An image processing based method for three-dimensional model reconstruction for numerical simulation was proposed,which presents a solution to the integration problem by a series of slice or projection images obtained by the post-processing modules of the numerical simulation software.By means of mapping image pixels to meshes of either finite difference or finite element models,the geometry contour can be extracted to export the stereolithography model.The values of results,represented by color,can be deduced and assigned to the meshes.All the models with data can be directly or indirectly integrated into other software as a continued or new numerical simulation.The three-dimensional reconstruction method has been validated in numerical simulation of castings and case studies were provided in this study. 展开更多
关键词 cross-platform numerical simulation 3D model reconstruction image processing SLICE
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Development of a toroidal soft x-ray imaging system and application for investigating three-dimensional plasma on J-TEXT
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作者 赵传旭 李建超 +9 位作者 张晓卿 王能超 丁永华 杨州军 江中和 严伟 李杨波 毛飞越 任正康 the J-TEXT Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期94-99,共6页
A toroidal soft x-ray imaging(T-SXRI)system has been developed to investigate threedimensional(3D)plasma physics on J-TEXT.This T-SXRI system consists of three sets of SXR arrays.Two sets are newly developed and locat... A toroidal soft x-ray imaging(T-SXRI)system has been developed to investigate threedimensional(3D)plasma physics on J-TEXT.This T-SXRI system consists of three sets of SXR arrays.Two sets are newly developed and located on the vacuum chamber wall at toroidal positionsφof 126.4°and 272.6°,respectively,while one set was established previously atφ=65.50.Each set of SXR arrays consists of three arrays viewing the plasma poloidally,and hence can be used separately to obtain SXR images via the tomographic method.The sawtooth precursor oscillations are measured by T-SXRI,and the corresponding images of perturbative SXR signals are successfully reconstructed at these three toroidal positions,hence providing measurement of the 3D structure of precursor oscillations.The observed 3D structure is consistent with the helical structure of the m/n=1/1 mode.The experimental observation confirms that the T-SXRI system is able to observe 3D structures in the J-TEXT plasma. 展开更多
关键词 SXR imaging J-TEXT tokamak three-dimensional measurement MHD
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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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Three-Dimensional Model Reconstruction of Nonwovens from Multi-Focus Images 被引量:2
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作者 董改革 王荣武 +1 位作者 李成族 尤祥银 《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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A novel technique of three-dimensional reconstruction segmentation and analysis for sliced images of biological tissues 被引量:3
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作者 李晶 赵海燕 +4 位作者 阮兴云 徐永清 孟伟正 李鲲鹏 张景强 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第12期1210-1212,共3页
A novel technique of three-dimensional (3D) reconstruction, segmentation, display and analysis of series slices of images including microscopic wide field optical sectioning by deconvolution method, cryo-electron micr... A novel technique of three-dimensional (3D) reconstruction, segmentation, display and analysis of series slices of images including microscopic wide field optical sectioning by deconvolution method, cryo-electron microscope slices by Fou-rier-Bessel synthesis and electron tomography (ET), and a series of computed tomography (CT) was developed to perform si-multaneous measurement on the structure and function of biomedical samples. The paper presents the 3D reconstruction seg-mentation display and analysis results of pollen spore, chaperonin, virus, head, cervical bone, tibia and carpus. At the same time, it also puts forward some potential applications of the new technique in the biomedical realm. 展开更多
关键词 生物组织 切片图象 三维重建分析 三维分割 X线断层摄影术
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Three-dimensional computed tomography reconstruction diagnosed digestive tract perforation and acute peritonitis caused by Monopterus albus:A case report
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作者 Jin-Han Yang Jin-Ying Lan +2 位作者 An-Yuan Lin Wei-Biao Huang Jin-Yuan Liao 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第10期2351-2356,共6页
BACKGROUND Few reports have described living foreign bodies in the human body.The current manuscript demonstrates that computed tomography(CT)is an effective tool for accurate preoperative evaluation of living foreign... BACKGROUND Few reports have described living foreign bodies in the human body.The current manuscript demonstrates that computed tomography(CT)is an effective tool for accurate preoperative evaluation of living foreign bodies in clinic.The threedimensional(3D)reconstruction technology could clearly display anatomical structures,lesions and adjacent organs,improving diagnostic accuracy and guiding the surgical decision-making process.CASE SUMMARY Herein we describe a 68-year-old man diagnosed with digestive tract perforation and acute peritonitis caused by a foreign body of Monopterus albus.The patient pre-sented to the emergency department with complaints of dull abdominal pain,profuse sweating and a pale complexion during work.A Monopterus albus had entered the patient’s body through the anus two hours ago.During hospitalization,the 3D reconstruction technology revealed a perforation of the middle rectum complicated with acute peritonitis and showed a clear and complete Monopterus albus bone morphology in the abdominal and pelvic cavities,with the Monopterus albus biting the mesentery.Laparoscopic examination detected a large(diameter of about 1.5 cm)perforation in the mid-rectum.It could be seen that a Monopterus albus had completely entered the abdominal cavity and had tightly bitten the mesentery of the small intestine.During the operation,the dead Monopterus albus was taken out.CONCLUSION The current manuscript demonstrates that CT is an effective tool for accurate preoperative evaluation of living foreign bodies in clinic. 展开更多
关键词 Digestive tract perforation Acute peritonitis Monopterus albus three-dimensional computed tomography reconstruction Case report
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A rapid micro-magnetic resonance imaging scanning for three-dimensional reconstruction of peripheral nerve fascicles 被引量:2
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作者 Zhi Yao Li-Wei Yan +7 位作者 Tao Wang Shuai Qiu Tao Lin Fu-Lin He Ru-Heng Yuan Xiao-Lin Liu Jian Qi Qing-Tang Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第11期1953-1960,共8页
The most common methods for three-dimensional reconstruction of peripheral nerve fascicles include histological and radiology techniques. Histological techniques have many drawbacks including an enormous manual worklo... The most common methods for three-dimensional reconstruction of peripheral nerve fascicles include histological and radiology techniques. Histological techniques have many drawbacks including an enormous manual workload and poor image registration. Micro-magnetic resonance imaging(Micro-MRI), an emerging radiology technique, has been used to report results in the brain, liver and tumor tissues. However, micro-MRI usage for obtaining intraneural structures has not been reported. The aim of this study was to present a new imaging method for three-dimensional reconstruction of peripheral nerve fascicles by ~1T micro-MRI. Freshly harvested sciatic nerve samples from an amputated limb were divided into four groups. Two different scanning conditions(Mannerist Solution/GD-DTPA contrast agent, distilled water) were selected, and both T1 and T2 phases programmed for each scanning condition. Three clinical surgeons evaluated the quality of the images via a standardized scale. Moreover, to analyze deformation of the two-dimensional image, the nerve diameter and total area of the micro-MRI images were compared after hematoxylin-eosin staining. The results show that rapid micro-MRI imaging method can be used for three-dimensional reconstruction of the fascicle structure. Nerve sample immersed in contrast agent(Mannerist Solution/GD-DTPA) and scanned in the T1 phase was the best. Moreover, the nerve sample was scanned freshly and can be recycled for other procedures. MRI images show better stability and smaller deformation compared with histological images. In conclusion, micro-MRI provides a feasible and rapid method for three-dimensional reconstruction of peripheral nerve fascicles, which can clearly show the internal structure of the peripheral nerve. 展开更多
关键词 nerve regeneration peripheral nerve fascicular three-dimensional reconstruction fascicular topography micro-magnetic resonanceimaging rapid acquired images contrast agent Mannerist Solution histological techniques deformation analysis peripheral nerve injury neural regeneration
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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 医学图像 图像处理 图像融合 三维重建
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Variational Reconstruction and Simulation Experiments of Sea Surface Wind Field for Ocean Data Buoy
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作者 LI Yunzhou HUANG Sixun +4 位作者 YAN Shen SUN Xuejin QI Suiping WANG Zhongqiu TANG Xiaoyu 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期577-582,共6页
The sea surface wind field is an important physical parameter in oceanography and meteorology.With the continuous refinement of numerical weather prediction,air-sea interface materials,energy exchange,and other studie... The sea surface wind field is an important physical parameter in oceanography and meteorology.With the continuous refinement of numerical weather prediction,air-sea interface materials,energy exchange,and other studies,three-dimensional(3D)wind field distribution at local locations on the sea surface must be measured accurately.The current in-situ observation of sea surface wind parameters is mainly achieved through the installation of wind sensors on ocean data buoys.However,the results obtained from this single-point measurement method cannot reflect wind field distribution in a vertical direction above the sea surface.Thus,the present paper proposes a theoretical framework for the optimal inversion of the 3D wind field structure variation in the area where the buoy is located.The variation analysis method is first used to reconstruct the wind field distribution at different heights of the buoy,after which theoretical analysis verification and numerical simulation experiments are conducted.The results indicate that the use of variational methods to reconstruct 3D wind fields is significantly effective in eliminating disturbance errors in observations,which also verifies the correctness of the theoretical analysis of this method.The findings of this article can provide a reference for the layout optimization design of wind measuring instruments in buoy observation systems and also provide theoretical guidance for the design of new observation buoys in the future. 展开更多
关键词 moored buoy three-dimensional wind field distribution variational analysis wind field reconstruction
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Ultrafast quasi-three-dimensional imaging 被引量:3
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作者 Yiling Lian Lan Jiang +2 位作者 Jingya Sun Jiadong Zhou Yao Zhou 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第4期501-512,共12页
Understanding laser induced ultrafast processes with complex three-dimensional(3D)geometries and extreme property evolution offers a unique opportunity to explore novel physical phenomena and to overcome the manufactu... Understanding laser induced ultrafast processes with complex three-dimensional(3D)geometries and extreme property evolution offers a unique opportunity to explore novel physical phenomena and to overcome the manufacturing limitations.Ultrafast imaging offers exceptional spatiotemporal resolution and thus has been considered an effective tool.However,in conventional single-view imaging techniques,3D information is projected on a two-dimensional plane,which leads to significant information loss that is detrimental to understanding the full ultrafast process.Here,we propose a quasi-3D imaging method to describe the ultrafast process and further analyze spatial asymmetries of laser induced plasma.Orthogonally polarized laser pulses are adopted to illuminate reflection-transmission views,and binarization techniques are employed to extract contours,forming the corresponding two-dimensional matrix.By rotating and multiplying the two-dimensional contour matrices obtained from the dual views,a quasi-3D image can be reconstructed.This successfully reveals dual-phase transition mechanisms and elucidates the diffraction phenomena occurring outside the plasma.Furthermore,the quasi-3D image confirms the spatial asymmetries of the picosecond plasma,which is difficult to achieve with two-dimensional images.Our findings demonstrate that quasi-3D imaging not only offers a more comprehensive understanding of plasma dynamics than previous imaging methods,but also has wide potential in revealing various complex ultrafast phenomena in related fields including strong-field physics,fluid dynamics,and cutting-edge manufacturing. 展开更多
关键词 ultrafast imaging extraction and reconstruction quasi-three-dimension plasma diffraction
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SAR regional all-azimuth observation orbit design for target 3D reconstruction
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作者 WANG Yanan ZHOU Chaowei +1 位作者 LIU Aifang MAO Qin 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期609-618,共10页
Three-dimensional(3D) synthetic aperture radar(SAR)extends the conventional 2D images into 3D features by several acquisitions in different aspects. Compared with 3D techniques via multiple observations in elevation, ... Three-dimensional(3D) synthetic aperture radar(SAR)extends the conventional 2D images into 3D features by several acquisitions in different aspects. Compared with 3D techniques via multiple observations in elevation, e.g. SAR interferometry(InSAR) and SAR tomography(TomoSAR), holographic SAR can retrieve 3D structure by observations in azimuth. This paper focuses on designing a novel type of orbit to achieve SAR regional all-azimuth observation(AAO) for embedded targets detection and holographic 3D reconstruction. The ground tracks of the AAO orbit separate the earth surface into grids. Target in these grids can be accessed with an azimuth angle span of360°, which is similar to the flight path of airborne circular SAR(CSAR). Inspired from the successive coverage orbits of optical sensors, several optimizations are made in the proposed method to ensure favorable grazing angles, the performance of 3D reconstruction, and long-term supervision for SAR sensors. Simulation experiments show the regional AAO can be completed within five hours. In addition, a second AAO of the same area can be duplicated in two days. Finally, an airborne SAR data process result is presented to illustrate the significance of AAO in 3D reconstruction. 展开更多
关键词 synthetic aperture radar(SAR) orbit design all-azimuth observation(AAO) three-dimensional(3D)reconstruction successive coverage
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Three-dimensional(3D)parametric measurements of individual gravels in the Gobi region using point cloud technique
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作者 JING Xiangyu HUANG Weiyi KAN Jiangming 《Journal of Arid Land》 SCIE CSCD 2024年第4期500-517,共18页
Gobi spans a large area of China,surpassing the combined expanse of mobile dunes and semi-fixed dunes.Its presence significantly influences the movement of sand and dust.However,the complex origins and diverse materia... Gobi spans a large area of China,surpassing the combined expanse of mobile dunes and semi-fixed dunes.Its presence significantly influences the movement of sand and dust.However,the complex origins and diverse materials constituting the Gobi result in notable differences in saltation processes across various Gobi surfaces.It is challenging to describe these processes according to a uniform morphology.Therefore,it becomes imperative to articulate surface characteristics through parameters such as the three-dimensional(3D)size and shape of gravel.Collecting morphology information for Gobi gravels is essential for studying its genesis and sand saltation.To enhance the efficiency and information yield of gravel parameter measurements,this study conducted field experiments in the Gobi region across Dunhuang City,Guazhou County,and Yumen City(administrated by Jiuquan City),Gansu Province,China in March 2023.A research framework and methodology for measuring 3D parameters of gravel using point cloud were developed,alongside improved calculation formulas for 3D parameters including gravel grain size,volume,flatness,roundness,sphericity,and equivalent grain size.Leveraging multi-view geometry technology for 3D reconstruction allowed for establishing an optimal data acquisition scheme characterized by high point cloud reconstruction efficiency and clear quality.Additionally,the proposed methodology incorporated point cloud clustering,segmentation,and filtering techniques to isolate individual gravel point clouds.Advanced point cloud algorithms,including the Oriented Bounding Box(OBB),point cloud slicing method,and point cloud triangulation,were then deployed to calculate the 3D parameters of individual gravels.These systematic processes allow precise and detailed characterization of individual gravels.For gravel grain size and volume,the correlation coefficients between point cloud and manual measurements all exceeded 0.9000,confirming the feasibility of the proposed methodology for measuring 3D parameters of individual gravels.The proposed workflow yields accurate calculations of relevant parameters for Gobi gravels,providing essential data support for subsequent studies on Gobi environments. 展开更多
关键词 Gobi gravels three-dimensional(3D)parameters point cloud 3D reconstruction Random Sample Consensus(RANSAC)algorithm Density-Based Spatial Clustering of Applications with Noise(DBSCAN)
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Deep learning-based magnetic resonance imaging reconstruction for improving the image quality of reduced-field-of-view diffusionweighted imaging of the pancreas 被引量:1
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作者 Yukihisa Takayama Keisuke Sato +3 位作者 Shinji Tanaka Ryo Murayama Nahoko Goto Kengo Yoshimitsu 《World Journal of Radiology》 2023年第12期338-349,共12页
BACKGROUND It has been reported that deep learning-based reconstruction(DLR)can reduce image noise and artifacts,thereby improving the signal-to-noise ratio and image sharpness.However,no previous studies have evaluat... BACKGROUND It has been reported that deep learning-based reconstruction(DLR)can reduce image noise and artifacts,thereby improving the signal-to-noise ratio and image sharpness.However,no previous studies have evaluated the efficacy of DLR in improving image quality in reduced-field-of-view(reduced-FOV)diffusionweighted imaging(DWI)[field-of-view optimized and constrained undistorted single-shot(FOCUS)]of the pancreas.We hypothesized that a combination of these techniques would improve DWI image quality without prolonging the scan time but would influence the apparent diffusion coefficient calculation.AIM To evaluate the efficacy of DLR for image quality improvement of FOCUS of the pancreas.METHODS This was a retrospective study evaluated 37 patients with pancreatic cystic lesions who underwent magnetic resonance imaging between August 2021 and October 2021.We evaluated three types of FOCUS examinations:FOCUS with DLR(FOCUS-DLR+),FOCUS without DLR(FOCUS-DLR−),and conventional FOCUS(FOCUS-conv).The three types of FOCUS and their apparent diffusion coefficient(ADC)maps were compared qualitatively and quantitatively.RESULTS FOCUS-DLR+(3.62,average score of two radiologists)showed significantly better qualitative scores for image noise than FOCUS-DLR−(2.62)and FOCUS-conv(2.88)(P<0.05).Furthermore,FOCUS-DLR+showed the highest contrast ratio and 600 s/mm^(2)(0.72±0.08 and 0.68±0.08)and FOCUS-DLR−showed the highest CR between cystic lesions and the pancreatic parenchyma for the b-values of 0 and 600 s/mm2(0.62±0.21 and 0.62±0.21)(P<0.05),respectively.FOCUS-DLR+provided significantly higher ADCs of the pancreas and lesion(1.44±0.24 and 3.00±0.66)compared to FOCUS-DLR−(1.39±0.22 and 2.86±0.61)and significantly lower ADCs compared to FOCUS-conv(1.84±0.45 and 3.32±0.70)(P<0.05),respectively.CONCLUSION This study evaluated the efficacy of DLR for image quality improvement in reduced-FOV DWI of the pancreas.DLR can significantly denoise images without prolonging the scan time or decreasing the spatial resolution.The denoising level of DWI can be controlled to make the images appear more natural to the human eye.However,this study revealed that DLR did not ameliorate pancreatic distortion.Additionally,physicians should pay attention to the interpretation of ADCs after DLR application because ADCs are significantly changed by DLR. 展开更多
关键词 Deep learning-based reconstruction Magnetic resonance imaging Reduced field-of-view Diffusion-weighted imaging PANCREAS
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Digital holographic imaging via direct quantum wavefunction reconstruction
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作者 胡孟军 张永生 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期50-57,共8页
Wavefunction is a fundamental concept of quantum theory.Recent studies have shown surprisingly that wavefunction can be directly reconstructed via the measurement of weak value.The weak value based direct wavefunction... Wavefunction is a fundamental concept of quantum theory.Recent studies have shown surprisingly that wavefunction can be directly reconstructed via the measurement of weak value.The weak value based direct wavefunction reconstruction not only gives the operational meaning of wavefunction,but also provides the possibility of realizing holographic imaging with a totally new quantum approach.Here,we review the basic background knowledge of weak value based direct wavefunction reconstruction combined with recent experimental demonstrations.The main purpose of this work focuses on the idea of holographic imaging via direct wavefunction reconstruction.Since research on this topic is still in its early stage,we hope that this work can attract interest in the field of traditional holographic imaging.In addition,the wavefunction holographic imaging may find important applications in quantum information science. 展开更多
关键词 wavefunction reconstruction weak value hologram imaging
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Artificial Intelligence-Based Image Reconstruction for Computed Tomography: A Survey
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作者 Quan Yan Yunfan Ye +3 位作者 Jing Xia Zhiping Cai Zhilin Wang Qiang Ni 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2545-2558,共14页
Computed tomography has made significant advances since its intro-duction in the early 1970s,where researchers have mainly focused on the quality of image reconstruction in the early stage.However,radiation exposure p... Computed tomography has made significant advances since its intro-duction in the early 1970s,where researchers have mainly focused on the quality of image reconstruction in the early stage.However,radiation exposure poses a health risk,prompting the demand of the lowest possible dose when carrying out CT examinations.To acquire high-quality reconstruction images with low dose radiation,CT reconstruction techniques have evolved from conventional reconstruction such as analytical and iterative reconstruction,to reconstruction methods based on artificial intelligence(AI).All these efforts are devoted to con-structing high-quality images using only low doses with fast reconstruction speed.In particular,conventional reconstruction methods usually optimize one aspect,while AI-based reconstruction has finally managed to attain all goals in one shot.However,there are limitations such as the requirements on large datasets,unstable performance,and weak generalizability in AI-based reconstruction methods.This work presents the review and discussion on the classification,the commercial use,the advantages,and the limitations of AI-based image reconstruction methods in CT. 展开更多
关键词 Computed tomography image reconstruction artificial intelligence
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Asymmetric image encryption algorithm based on a new three-dimensional improved logistic chaotic map
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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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