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Sparse-view neutron CT 3D image reconstruction algorithm based on split Bregman method
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作者 Teng-Fei Zhu Yang Liu +1 位作者 Zhi Luo Xiao-Ping Ouyang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第9期41-55,共15页
As a complement to X-ray computed tomography(CT),neutron tomography has been extensively used in nuclear engineer-ing,materials science,cultural heritage,and industrial applications.Reconstruction of the attenuation m... As a complement to X-ray computed tomography(CT),neutron tomography has been extensively used in nuclear engineer-ing,materials science,cultural heritage,and industrial applications.Reconstruction of the attenuation matrix for neutron tomography with a traditional analytical algorithm requires hundreds of projection views in the range of 0°to 180°and typically takes several hours to complete.Such a low time-resolved resolution degrades the quality of neutron imaging.Decreasing the number of projection acquisitions is an important approach to improve the time resolution of images;however,this requires efficient reconstruction algorithms.Therefore,sparse-view reconstruction algorithms in neutron tomography need to be investigated.In this study,we investigated the three-dimensional reconstruction algorithm for sparse-view neu-tron CT scans.To enhance the reconstructed image quality of neutron CT,we propose an algorithm that uses OS-SART to reconstruct images and a split Bregman to solve for the total variation(SBTV).A comparative analysis of the performances of each reconstruction algorithm was performed using simulated and actual experimental data.According to the analyzed results,OS-SART-SBTV is superior to the other algorithms in terms of denoising,suppressing artifacts,and preserving detailed structural information of images. 展开更多
关键词 Neutron CT OS-SART Sparse-view 3d reconstruction Split Bregman Total variation
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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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Efficacy of laparoscopic low anterior resection for colorectal cancer patients with 3D-vascular reconstruction for left coronary artery preservation
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作者 Ye Wang Zhi-Sheng Liu +2 位作者 Zong-Bao Wang Shawn Liu Feng-Bo Sun 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1548-1557,共10页
BACKGROUND Laparoscopic low anterior resection(LLAR)has become a mainstream surgical method for the treatment of colorectal cancer,which has shown many advantages in the aspects of surgical trauma and postoperative re... BACKGROUND Laparoscopic low anterior resection(LLAR)has become a mainstream surgical method for the treatment of colorectal cancer,which has shown many advantages in the aspects of surgical trauma and postoperative rehabilitation.However,the effect of surgery on patients'left coronary artery and its vascular reconstruction have not been deeply discussed.With the development of medical imaging technology,3D vascular reconstruction has become an effective means to evaluate the curative effect of surgery.AIM To investigate the clinical value of preoperative 3D vascular reconstruction in LLAR of rectal cancer with the left colic artery(LCA)preserved.METHODS A retrospective cohort study was performed to analyze the clinical data of 146 patients who underwent LLAR for rectal cancer with LCA preservation from January to December 2023 in our hospital.All patients underwent LLAR of rectal cancer with the LCA preserved,and the intraoperative and postoperative data were complete.The patients were divided into a reconstruction group(72 patients)and a nonreconstruction group(74 patients)according to whether 3D vascular reconstruction was performed before surgery.The clinical features,operation conditions,complications,pathological results and postoperative recovery of the two groups were collected and compared.RESULTS A total of 146 patients with rectal cancer were included in the study,including 72 patients in the reconstruction group and 74 patients in the nonreconstruction group.There were 47 males and 25 females in the reconstruction group,aged(59.75±6.2)years,with a body mass index(BMI)(24.1±2.2)kg/m^(2),and 51 males and 23 females in the nonreconstruction group,aged(58.77±6.1)years,with a BMI(23.6±2.7)kg/m^(2).There was no significant difference in the baseline data between the two groups(P>0.05).In the submesenteric artery reconstruction group,35 patients were type Ⅰ,25 patients were type Ⅱ,11 patients were type Ⅲ,and 1 patient was type Ⅳ.There were 37 type Ⅰ patients,24 type Ⅱ patients,12 type Ⅲ patients,and 1 type Ⅳ patient in the nonreconstruction group.There was no significant difference in arterial typing between the two groups(P>0.05).The operation time of the reconstruction group was 162.2±10.8 min,and that of the nonreconstruction group was 197.9±19.1 min.Compared with that of the reconstruction group,the operation time of the two groups was shorter,and the difference was statistically significant(t=13.840,P<0.05).The amount of intraoperative blood loss was 30.4±20.0 mL in the reconstruction group and 61.2±26.4 mL in the nonreconstruction group.The amount of blood loss in the reconstruction group was less than that in the control group,and the difference was statistically significant(t=-7.930,P<0.05).The rates of anastomotic leakage(1.4%vs 1.4%,P=0.984),anastomotic hemorrhage(2.8%vs 4.1%,P=0.672),and postoperative hospital stay(6.8±0.7 d vs 7.0±0.7 d,P=0.141)were not significantly different between the two groups.CONCLUSION Preoperative 3D vascular reconstruction technology can shorten the operation time and reduce the amount of intraoperative blood loss.Preoperative 3D vascular reconstruction is recommended to provide an intraoperative reference for laparoscopic low anterior resection with LCA preservation. 展开更多
关键词 Laparoscopic low anterior resection 3d vascular reconstruction Coronary artery Colorectal cancer Retrospective cohort study
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Multi-View Image-Based 3D Reconstruction in Indoor Scenes:A Survey
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作者 LU Ping SHI Wenzhe QIAO Xiuquan 《ZTE Communications》 2024年第3期91-98,共8页
Three-dimensional reconstruction technology plays an important role in indoor scenes by converting objects and structures in indoor environments into accurate 3D models using multi-view RGB images.It offers a wide ran... Three-dimensional reconstruction technology plays an important role in indoor scenes by converting objects and structures in indoor environments into accurate 3D models using multi-view RGB images.It offers a wide range of applications in fields such as virtual reality,augmented reality,indoor navigation,and game development.Existing methods based on multi-view RGB images have made significant progress in 3D reconstruction.These image-based reconstruction methods not only possess good expressive power and generalization performance,but also handle complex geometric shapes and textures effectively.Despite facing challenges such as lighting variations,occlusion,and texture loss in indoor scenes,these challenges can be effectively addressed through deep neural networks,neural implicit surface representations,and other techniques.The technology of indoor 3D reconstruction based on multi-view RGB images has a promising future.It not only provides immersive and interactive virtual experiences but also brings convenience and innovation to indoor navigation,interior design,and virtual tours.As the technology evolves,these image-based reconstruction methods will be further improved to provide higher quality and more accurate solutions to indoor scene reconstruction. 展开更多
关键词 3d reconstruction MVS NeRF neural implicit surface
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Equilibrium reconstruction method for self-organized plasmas on reversed field pinches with polarimeter-interferometer
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作者 Yuhua HUANG Ke LIU +17 位作者 Wenzhe MAO Caoxiang ZHU Tao LAN Yiming ZU Yongkang ZHOU Xingkang WANG Peng DENG Li WANG Pai PENG Adi LIU Chu ZHOU Haifeng LIU Hong LI Jinlin XIE Yuhong XU Weixing DING Wandong LIU Ge ZHUANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第12期31-40,共10页
In the reversed field pinch(RFP),plasmas exhibit various self-organized states.Among these,the three-dimensional(3D)helical state known as the“quasi-single-helical”(QSH)state enhances RFP confinement.However,accurat... In the reversed field pinch(RFP),plasmas exhibit various self-organized states.Among these,the three-dimensional(3D)helical state known as the“quasi-single-helical”(QSH)state enhances RFP confinement.However,accurately describing the equilibrium is challenging due to the presence of 3D structures,magnetic islands,and chaotic regions.It is difficult to obtain a balance between the available diagnostic and the real equilibrium structure.To address this issue,we introduce KTX3DFit,a new 3D equilibrium reconstruction code specifically designed for the Keda Torus eXperiment(KTX)RFP.KTX3DFit utilizes the stepped-pressure equilibrium code(SPEC)to compute 3D equilibria and uses polarimetric interferometer signals from experiments.KTX3DFit is able to reconstruct equilibria in various states,including axisymmetric,doubleaxis helical(DAx),and single-helical-axis(SHAx)states.Notably,this study marks the first integration of the SPEC code with internal magnetic field data for equilibrium reconstruction and could be used for other 3D configurations. 展开更多
关键词 equilibrium reconstruction polarimeter-interferometer multi-region relaxed MHd 3d self-organized states reversed field pinch
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Comparison of Efficacy between 3D Navigation-Assisted Percutaneous Iliosacral Screw and Minimally Invasive Reconstruction Plate in Treating Sacroiliac Complex Injury 被引量:3
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作者 Qi-lin LU Yi-liang ZHU +5 位作者 Xu-gui LI Wei XIE Xiao-zhen WANG Xue-zhen SHAO Xian-hua CAI Xi-ming LIU 《Current Medical Science》 SCIE CAS 2019年第1期81-87,共7页
The clinical efficacy was compared between 3D navigation-assisted percutaneous iliosacral screw(3DPS)and minimally invasive reconstruction plate(MIRP)in treating sacroiliac complex injury and the surgical procedures o... The clinical efficacy was compared between 3D navigation-assisted percutaneous iliosacral screw(3DPS)and minimally invasive reconstruction plate(MIRP)in treating sacroiliac complex injury and the surgical procedures of 3DPS were introduced.A retrospective analysis was performed on 49 patients with sacroiliac complex injury from March 2013 to May 2017.Twenty-one cases were treated by 3DPS,and 28 cases by MIRP.Intraoperative indexes as operative time,blood loss,incision length,length of hospital stay and postoperative complications were respectively documented.Quality of reduction was postoperatively evaluated by Matta radiological criteria,and clinical effect was assessed by Majeed scoring criteria at the last followup.Operative time and hospital stay were significantly shortened,and blood loss,and incision length were significantly reduced in 3DPS group as compared with those in MIRP group(P<0.05).No statistically significant difference was found between 3DPS group and MIRP group in the assessment of reduction and function(P>0.05).It was concluded that both 3DPS and MIRP can effectively treat the sacroiliac complex injury,and 3DPS can provide an accurate,safe and minimally invasive fixation with shorter operative time and hospital stay. 展开更多
关键词 SACROILIAC complex injury 3d navigation-assisted system PERCUTANEOUS iliosacral SCREW MINIMALLY INVASIVE reconstruction plate
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3D Shape Reconstruction of Lumbar Vertebra From Two X-ray Images and a CT Model 被引量:3
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作者 Longwei Fang Zuowei Wang +3 位作者 Zhiqiang Chen Fengzeng Jian Shuo Li Huiguang He 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2020年第4期1124-1133,共10页
Structure reconstruction of 3 D anatomy from biplanar X-ray images is a challenging topic. Traditionally, the elastic-model-based method was used to reconstruct 3 D shapes by deforming the control points on the elasti... Structure reconstruction of 3 D anatomy from biplanar X-ray images is a challenging topic. Traditionally, the elastic-model-based method was used to reconstruct 3 D shapes by deforming the control points on the elastic mesh. However, the reconstructed shape is not smooth because the limited control points are only distributed on the edge of the elastic mesh.Alternatively, statistical-model-based methods, which include shape-model-based and intensity-model-based methods, are introduced due to their smooth reconstruction. However, both suffer from limitations. With the shape-model-based method, only the boundary profile is considered, leading to the loss of valid intensity information. For the intensity-based-method, the computation speed is slow because it needs to calculate the intensity distribution in each iteration. To address these issues, we propose a new reconstruction method using X-ray images and a specimen’s CT data. Specifically, the CT data provides both the shape mesh and the intensity model of the vertebra. Intensity model is used to generate the deformation field from X-ray images, while the shape model is used to generate the patient specific model by applying the calculated deformation field.Experiments on the public synthetic dataset and clinical dataset show that the average reconstruction errors are 1.1 mm and1.2 mm, separately. The average reconstruction time is 3 minutes. 展开更多
关键词 2d/2d registration 2d/3d registration 3d reconstruction vertebra model X-ray image
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祖先序列重建增强D-阿洛酮糖3-差向异构酶的热稳定性
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作者 管立军 朱玲 +7 位作者 王崑仑 李家磊 高扬 严松 张馨笛 陈晴 季妮娜 李波 《食品工业科技》 CAS 北大核心 2024年第21期121-128,共8页
为解决现有D-阿洛酮糖3-差向异构酶(DAEase)热稳定性差的产业问题,本文采用系统发育指导的大数据挖掘、合理修饰和祖先序列重建策略(ASR),重建了具有不同催化结构域DAEase的祖先序列,构建了表达载体,通过重组表达与分子对接筛选出了DAEa... 为解决现有D-阿洛酮糖3-差向异构酶(DAEase)热稳定性差的产业问题,本文采用系统发育指导的大数据挖掘、合理修饰和祖先序列重建策略(ASR),重建了具有不同催化结构域DAEase的祖先序列,构建了表达载体,通过重组表达与分子对接筛选出了DAEase A13并进行酶学性质表征,此外,还基于结构分析与分子动力学模拟揭示了DAEase A13热稳定性增强的分子机制。结果表明,基于ASR策略所构建的A13 70℃时半衰期可达8.4 h,其热稳定性较野生(WT)酶显著增强,最大转化率为31%,催化活性也略高于WT酶。立体结构模拟与分子动力学模拟揭示了ASR A13中大量氢键和疏水作用的增加维持了高温下酶分子结构的稳定性,是其热稳定性增强的主要因素。研究结果证实了ASR策略可以改造DAEase使其稳定性、活性和混杂性增强,可以为D-阿洛酮糖工业生产提供良好的生物催化剂。 展开更多
关键词 祖先序列重建 d-阿洛酮糖 d-阿洛酮糖3-差向异构酶 热稳定性
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3D Reconstruction for Motion Blurred Images Using Deep Learning-Based Intelligent Systems 被引量:4
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作者 Jing Zhang Keping Yu +2 位作者 Zheng Wen Xin Qi Anup Kumar Paul 《Computers, Materials & Continua》 SCIE EI 2021年第2期2087-2104,共18页
The 3D reconstruction using deep learning-based intelligent systems can provide great help for measuring an individual’s height and shape quickly and accurately through 2D motion-blurred images.Generally,during the a... The 3D reconstruction using deep learning-based intelligent systems can provide great help for measuring an individual’s height and shape quickly and accurately through 2D motion-blurred images.Generally,during the acquisition of images in real-time,motion blur,caused by camera shaking or human motion,appears.Deep learning-based intelligent control applied in vision can help us solve the problem.To this end,we propose a 3D reconstruction method for motion-blurred images using deep learning.First,we develop a BF-WGAN algorithm that combines the bilateral filtering(BF)denoising theory with a Wasserstein generative adversarial network(WGAN)to remove motion blur.The bilateral filter denoising algorithm is used to remove the noise and to retain the details of the blurred image.Then,the blurred image and the corresponding sharp image are input into the WGAN.This algorithm distinguishes the motion-blurred image from the corresponding sharp image according to the WGAN loss and perceptual loss functions.Next,we use the deblurred images generated by the BFWGAN algorithm for 3D reconstruction.We propose a threshold optimization random sample consensus(TO-RANSAC)algorithm that can remove the wrong relationship between two views in the 3D reconstructed model relatively accurately.Compared with the traditional RANSAC algorithm,the TO-RANSAC algorithm can adjust the threshold adaptively,which improves the accuracy of the 3D reconstruction results.The experimental results show that our BF-WGAN algorithm has a better deblurring effect and higher efficiency than do other representative algorithms.In addition,the TO-RANSAC algorithm yields a calculation accuracy considerably higher than that of the traditional RANSAC algorithm. 展开更多
关键词 3d reconstruction motion blurring deep learning intelligent systems bilateral filtering random sample consensus
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A Systematic Approach for Making 3D-Printed Patient-Specific Implants for Craniomaxillofacial Reconstruction 被引量:3
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作者 Ruxu Du Yu-Xiong Su +7 位作者 Yu Yan Wing Shan Choi Wei-Fa Yang Chunyu Zhang Xianshuai Chen Justin Paul Curtin Jianglin Ouyang Bitao Zhang 《Engineering》 SCIE EI 2020年第11期1291-1301,共11页
Craniomaxillofacial reconstruction implants,which are extensively used in head and neck surgery,are conventionally made in standardized forms.During surgery,the implant must be bended manually to match the anatomy of ... Craniomaxillofacial reconstruction implants,which are extensively used in head and neck surgery,are conventionally made in standardized forms.During surgery,the implant must be bended manually to match the anatomy of the individual bones.The bending process is time-consuming,especially for inexperienced surgeons.Moreover,repetitive bending may induce undesirable internal stress concentration,resulting in fatigue under masticatory loading in v iv o and causing various complications such as implant fracture,screw loosening,and bone resorption.There have been reports on the use of patient-specific 3D-printed implants for craniomaxillofacial reconstruction,although few reports have considered implant quality.In this paper,we present a systematic approach for making 3D-printed patientspecific surgical implants for craniomaxillofacial reconstruction.The approach consists of three parts:First,an easy-to-use design module is developed using Solidworks®software,which helps surgeons to design the implants and the axillary fixtures for surgery.Design engineers can then carry out the detailed design and use finite-element modeling(FEM)to optimize the design.Second,the fabrication process is carried out in three steps:0 testing the quality of the powder;(2)setting up the appropriate process parameters and running the 3D printing process;and (3)conducting post-processing treatments(i.e.,heat and surface treatments)to ensure the quality and performance of the implant.Third,the operation begins after the final checking of the implant and sterilization.After the surgery,postoperative rehabilitation follow-up can be carried out using our patient tracking software.Following this systematic approach,we have successfully conducted a total of 41 surgical cases.3D-printed patient-specific implants have a number of advantages;in particular,their use reduces surgery time and shortens patient recovery time.Moreover,the presented approach helps to ensure implant quality. 展开更多
关键词 Patient-specific implant Craniomaxillofacial reconstruction 3d printing Surgery
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First-principles Study on Geometric and Electronic Structures of Si(111)-√7× √3-In Surface Reconstruction
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作者 商波 袁岚峰 杨金龙 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第4期403-408,I0003,共7页
In order to determine the structures of Si(111)-√7 √3-In surfaces and to understand their electronic properties, we construct six models of both hexagonal and rectangular types and perform first-principles calcula... In order to determine the structures of Si(111)-√7 √3-In surfaces and to understand their electronic properties, we construct six models of both hexagonal and rectangular types and perform first-principles calculations. Their scanning tunneling microscopic images and work functions are simulated and compared with experimental results. In this way, the hex-H3' and rect-T1 models are identified as the experimental configurations for the hexagonal and rectangular types, respectively. The structural evolution mechanism of the In/Si(lll) surface with indium coverage around 1.0 monolayer is discussed. The 4×1 and -√7× √3 phases are suggested to have two different types of evolution mechanisms, consistent with experimental results. 展开更多
关键词 Surface reconstruction Si(111)-√7× 3In density functional theory Scanning tunnueling microscopic image
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Application of computer tomography-based 3D reconstruction technique in hernia repair surgery 被引量:2
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作者 Feng Wang Xiao-Feng Yang 《World Journal of Clinical Cases》 SCIE 2020年第23期5944-5951,共8页
BACKGROUND Hernia is a common condition requiring abdominal surgery.The current standard treatment for hernia is tension-free repair using meshes.Globally,more than 200 new types of meshes are licensed each year.Howev... BACKGROUND Hernia is a common condition requiring abdominal surgery.The current standard treatment for hernia is tension-free repair using meshes.Globally,more than 200 new types of meshes are licensed each year.However,their clinical applications are associated with a series of complications,such as recurrence(10%-24%)and infection(0.5%-9.0%).In contrast,3D-printed meshes have significantly reduced the postoperative complications in patients.They have also shortened operating time and minimized the loss of mesh materials.In this study,we used the myopectineal orifice(MPO)data obtained from preoperative computer tomography(CT)-based 3D reconstruction for the production of 3D-printed biologic meshes.AIM To investigate the application of multislice spiral CT-based 3D reconstruction technique in 3D-printed biologic mesh for hernia repair surgery.METHODS We retrospectively analyzed 60 patients who underwent laparoscopic tension-free repair for inguinal hernia in the Department of General Surgery of the First Hospital of Shanxi Medical University from September 2019 to December 2019.This study included 30 males and 30 females,with a mean age of 40±5.6 years.Data on the MPO were obtained from preoperative CT-based 3D reconstruction as well as from real-world intraoperative measurements for all patients.Anatomic points were set for the purpose of measurement based on the definition of MPO:A:The pubic tubercle;B:Intersection of the horizontal line extending from the summit of the inferior edge of the internal oblique and transversus abdominis and the outer edge of the rectus abdominis,C:Intersection of the horizontal line extending from the summit of the inferior edge of the internal oblique and transversus abdominis and the inguinal ligament,D:Intersection of the iliopsoas muscle and the inguinal ligament,and E:Intersection of the iliopsoas muscle and the superior pubic ramus.The distance between the points was measured.All preoperative and intraoperative data were analyzed using the t test.Differences with P<0.05 were considered significant in comparative analysis.RESULTS The distance between points AB,AC,BC,DE,and AE based on preoperative and intraoperative data was 7.576±0.212 cm vs 7.573±0.266 cm,7.627±0.212 cm vs 7.627±0.212 cm,7.677±0.229 cm vs 7.567±0.786 cm,7.589±0.204 cm vs 7.512±0.21 cm,and 7.617±0.231 cm vs 7.582±0.189 cm,respectively.All differences were not statistically significant(P>0.05).CONCLUSION The use of multislice spiral CT-based 3D reconstruction technique before hernia repair surgery allows accurate measurement of data and relationships of different anatomic sites in the MPO region.This technique can provide precise data for the production of 3D-printed biologic meshes. 展开更多
关键词 HERNIA INGUINAL Myopectineal orifice 3d-printed biologic meshes Computer tomography-based 3d reconstruction Inguinal hernia
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Deep-Learning-Empowered 3D Reconstruction for Dehazed Images in IoT-Enhanced Smart Cities 被引量:2
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作者 Jing Zhang Xin Qi +1 位作者 San Hlaing Myint Zheng Wen 《Computers, Materials & Continua》 SCIE EI 2021年第8期2807-2824,共18页
With increasingly more smart cameras deployed in infrastructure and commercial buildings,3D reconstruction can quickly obtain cities’information and improve the efficiency of government services.Images collected in o... With increasingly more smart cameras deployed in infrastructure and commercial buildings,3D reconstruction can quickly obtain cities’information and improve the efficiency of government services.Images collected in outdoor hazy environments are prone to color distortion and low contrast;thus,the desired visual effect cannot be achieved and the difficulty of target detection is increased.Artificial intelligence(AI)solutions provide great help for dehazy images,which can automatically identify patterns or monitor the environment.Therefore,we propose a 3D reconstruction method of dehazed images for smart cities based on deep learning.First,we propose a fine transmission image deep convolutional regression network(FT-DCRN)dehazing algorithm that uses fine transmission image and atmospheric light value to compute dehazed image.The DCRN is used to obtain the coarse transmission image,which can not only expand the receptive field of the network but also retain the features to maintain the nonlinearity of the overall network.The fine transmission image is obtained by refining the coarse transmission image using a guided filter.The atmospheric light value is estimated according to the position and brightness of the pixels in the original hazy image.Second,we use the dehazed images generated by the FT-DCRN dehazing algorithm for 3D reconstruction.An advanced relaxed iterative fine matching based on the structure from motion(ARI-SFM)algorithm is proposed.The ARISFM algorithm,which obtains the fine matching corner pairs and reduces the number of iterations,establishes an accurate one-to-one matching corner relationship.The experimental results show that our FT-DCRN dehazing algorithm improves the accuracy compared to other representative algorithms.In addition,the ARI-SFM algorithm guarantees the precision and improves the efficiency. 展开更多
关键词 3d reconstruction dehazed image deep learning fine transmission image structure from motion algorithm
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PCA-based 3D Shape Reconstruction of Human Foot Using Multiple Viewpoint Cameras 被引量:2
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作者 Edmée Amstutz Tomoaki Teshima +2 位作者 Makoto Kimura Masaaki Mochimaru Hideo Saito 《International Journal of Automation and computing》 EI 2008年第3期217-225,共9页
This paper describes a multiple camera-based method to reconstruct the 3D shape of a human foot. From a foot database, an initial 3D model of the foot represented by a cloud of points is built. The shape parameters, w... This paper describes a multiple camera-based method to reconstruct the 3D shape of a human foot. From a foot database, an initial 3D model of the foot represented by a cloud of points is built. The shape parameters, which can characterize more than 92% of a foot, are defined by using the principal component analysis method. Then, using "active shape models", the initial 3D model is adapted to the real foot captured in multiple images by applying some constraints (edge points' distance and color variance). We insist here on the experiment part where we demonstrate the efficiency of the proposed method on a plastic foot model, and also on real human feet with various shapes. We propose and compare different ways of texturing the foot which is needed for reconstruction. We present an experiment performed on the plastic foot model and on human feet and propose two different ways to improve the final 3D shapers accuracy according to the previous experiments' results. The first improvement proposed is the densification of the cloud of points used to represent the initial model and the foot database. The second improvement concerns the projected patterns used to texture the foot. We conclude by showing the obtained results for a human foot with the average computed shape error being only 1.06 mm. 展开更多
关键词 Shape measurement 3d reconstruction from multiview cameras principal component analysis
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Using on-site liver 3-D reconstruction and volumetric calculations in split liver transplantation 被引量:3
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作者 Trevor W Reichman Brittany Fiorello +5 位作者 Ian Carmody Humberto Bohorquez Ari Cohen John Seal David Bruce George E Loss 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2016年第6期587-592,共6页
BACKGROUND: Split liver transplantation increases the number of grafts available for transplantation. Pre-recovery assessment of liver graft volume is essential for selecting suitable recipients. The purpose of this ... BACKGROUND: Split liver transplantation increases the number of grafts available for transplantation. Pre-recovery assessment of liver graft volume is essential for selecting suitable recipients. The purpose of this study was to determine the ability and feasibility of constructing a 3-D model to aid in surgical planning and to predict graft weight prior to an in situ division of the donor liver. METHODS: Over 11 months, 3-D volumetric reconstruction of 4 deceased donors was performed using Pathfinder Scout liver volumetric software. Demographic, laboratory, operative, perioperative and survival data for these patients along with donor demographic data were collected prospectively and analyzed retrospectively. RESULTS: The average predicted weight of the grafts from the adult donors obtained from an in situ split procedure were 1130 g (930-1458 g) for the extended right lobe donors and 312 g (222-396 g) for left lateral segment grafts. Actual adult graft weight was 92% of the predicted weight for both the extended right grafts and the left lateral segment grafts. The predicted and actual graft weights for the pediatric donors were 176 g and 210 g for the left lateral segment grafts and 308 g and 280 g for the extended right lobe grafts,respectively. All grafts were transplanted except for the right lobe from the pediatric donors due to the small graft weight.CONCLUSIONS: On-site volumetric assessment of donors provides useful information for the planning of an in situ split and for selection of recipients. This information may expand the donor pool to recipients previously felt to be unsuitable due to donor and/or recipient weight. 展开更多
关键词 split liver transplantation reduced-size liver transplantation 3-d reconstruction
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Low-Cost CSI Using Forensic GPR, 3D Reconstruction, and GIS 被引量:1
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作者 Pier Matteo Barone Rosa Maria Di Maggio 《Journal of Geographic Information System》 2019年第5期493-499,共7页
At a time in which several law enforcement agencies all around the world are facing severe expenditure reviews, the increasing use of low-cost solutions during crime scene investigations (CSI) can be a sustainable sol... At a time in which several law enforcement agencies all around the world are facing severe expenditure reviews, the increasing use of low-cost solutions during crime scene investigations (CSI) can be a sustainable solution without being detracting from a scientific and rigorous forensic approach. Recently, some private companies are trying to satisfy the growing needs of the police to have cheaper and faster techniques to survey crime scenes and to obtain results with scientifically high-level outputs, more or less comparable with similar outputs from more expensive instruments. This paper reported results from a crime scene in which a low-cost GPR instrument, a free 3D photogrammetry software, and an open-source geographical information system (GIS) were deployed. The collection, processing, and analyses of these data will provide a very promising starting point for future low-cost and professional applications. 展开更多
关键词 GPR CSI Forensic GEOSCIENCE 3d reconstruction GIS
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3D打印技术用于经鼻蝶窦入路垂体腺瘤切除术应用效果及对血清MMP-9和IGF-1水平的影响
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作者 韩莹 陈兴河 +2 位作者 王永恒 赵锦程 吴磊 《中国医学装备》 2024年第4期112-116,共5页
目的:探究3D打印技术在经鼻蝶窦入路垂体腺瘤(PA)切除术的应用效果及对血清基质金属蛋白酶-9(MMP-9)和胰岛素样生长因子-1(IGF-1)水平的影响。方法:选取2020年5月至2022年5月秦皇岛市第一医院收治的84例PA患者,按照随机数表法将其分为... 目的:探究3D打印技术在经鼻蝶窦入路垂体腺瘤(PA)切除术的应用效果及对血清基质金属蛋白酶-9(MMP-9)和胰岛素样生长因子-1(IGF-1)水平的影响。方法:选取2020年5月至2022年5月秦皇岛市第一医院收治的84例PA患者,按照随机数表法将其分为观察组和对照组,每组42例。对照组行经鼻蝶窦入路垂体腺瘤切除术,观察组行经鼻蝶窦入路垂体腺瘤切除术联合应用3D打印技术,比较两组肿瘤切除效果、围术期指标、视力改善情况、MMP-9和IGF-1水平,以及鼻腔功能的鼻气道阻力(NAR)、T&T嗅觉测试评分及并发症。结果:观察组肿瘤切除效果优于对照组,差异有统计学意义(U=2.286,P<0.05);观察组手术时间、术中出血量及住院时间均少于对照组,差异有统计学意义(t=4.780、11.438、11.842,P<0.05);术后3 d、7 d时观察组血清MMP-9和IGF-1水平低于对照组,差异有统计学意义(F=7.526、4.985,P<0.05);术后1个月、3个月时观察组NAR及T&T嗅觉测试评分低于对照组,差异有统计学意义(F=6.359、8.436,P<0.05);两组视力视野改善情况及并发症发生率比较,差异无统计学意义(P>0.05)。结论:3D打印技术用于经鼻蝶窦入路垂体腺瘤切除术可提高肿瘤切除效果,优化手术操作,减少创伤,有利于减轻疼痛,改善嗅觉功能与视力视野,并能降低血清MMP-9、IGF-1水平,且安全性较高。 展开更多
关键词 垂体腺瘤 经鼻蝶窦入路垂体腺瘤(PA)切除术 3d打印技术 基质金属蛋白酶-9(MMP-9) 胰岛素样生长因子-1(IGF-1)
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骨质疏松症患者PINP、25-(OH)VitD_(3)、BMP-2与中医辨证分型的相关性研究
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作者 刘莎莎 郭洪科 《四川中医》 2024年第6期87-91,共5页
目的:分析骨质疏松症患者血清总I型胶原氨基末端前肽(PINP)、25-羟维生素D3[25-(OH)VitD_(3)]及骨形态发生蛋白2(BMP-2)与其中医辨证分型的相关性。方法:收集我院2020年8月~2023年8月医院收治的157例骨质疏松症患者的一般资料及中医四... 目的:分析骨质疏松症患者血清总I型胶原氨基末端前肽(PINP)、25-羟维生素D3[25-(OH)VitD_(3)]及骨形态发生蛋白2(BMP-2)与其中医辨证分型的相关性。方法:收集我院2020年8月~2023年8月医院收治的157例骨质疏松症患者的一般资料及中医四诊资料进行回顾性分析,并统计骨质疏松症患者中医辨证分型结果,对不同症型患者基本资料、PINP、25-(OH)VitD_(3)、BMP-2水平进行比较。结果:157例骨质疏松症患者中医辨证分型属肾阳虚证34例,脾肾阳虚证43例,肝肾阴虚证49例,血瘀气滞证31例。不同中医辨证分型的骨质疏松患者血清PINP、25-(OH)VitD_(3)及BMP-2水平整体相比,差异有统计学意义(P<0.05);其中,血瘀气滞组PINP水平显著高于肾阳虚组、脾肾阳虚组及肝肾阴虚组患者(P<0.05),而其余3组两两间相比,差异无统计学意义(P>0.05);脾肾阳虚证患者25-(OH)VitD_(3)水平明显低于肾阳虚组、肝肾阴虚组及血瘀气滞组(P<0.05),且肾阳虚组低于肝肾阴虚组及血瘀气滞组(P<0.05),而其余两组相比差异无统计学意义(P>0.05);血瘀气滞组BMP-2水平显著低于肾阳虚组、脾肾阳虚组及肝肾阴虚组患者(P<0.05),而其余3组两两间相比,差异无统计学意义(P>0.05);二分类logistics回归分析结果显示,血瘀气滞与PINP呈正相关(P<0.05),与BMP-2呈负相关(P<0.05);脾肾阳虚与25-(OH)VitD_(3)呈负相关(P<0.05)。结论:骨质疏松症患者的血清PINP、25-(OH)VitD_(3)、BMP-2水平与其中医辨证分型具有一定相关性,可作为评估患者中医辨证分型的参考指标。 展开更多
关键词 骨质疏松症 总I型胶原氨基末端前肽 25-羟维生素d3 骨形态发生蛋白2 中医辨证分型
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儿童矮小症与25羟基维生素D,IGF-1,IGFBP-3的相关性
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作者 王辉 栾生林 《贵州医药》 2024年第1期78-79,共2页
目的探讨儿童矮小症与25-(OH)D、IGF-1、IGFBP-3的相关性。方法以60例儿童矮小症作为观察组;另选择同期于本院体检健康的儿童32例作为参照组。采用化学发光免疫分析法测定IGF-1,IGFBP-3表达;采取酶联免疫吸附试验对血清内的25-(OH)D含... 目的探讨儿童矮小症与25-(OH)D、IGF-1、IGFBP-3的相关性。方法以60例儿童矮小症作为观察组;另选择同期于本院体检健康的儿童32例作为参照组。采用化学发光免疫分析法测定IGF-1,IGFBP-3表达;采取酶联免疫吸附试验对血清内的25-(OH)D含量开展检测。比较两组25-(OH)D、IGF-1、IGFBP-3表达阳性率,分析其与儿童矮小症的相关性。结果入组儿童的性别、年龄以及父母身高比较无差异(P>0.05);相比参照组,矮小症三组患儿的25-(OH)D、IGF-1、IGFBP-3均呈下降趋势,其中ISS组、PGHD组的25-(OH)D、IGF-1、IGFBP-3水平高于CGHD组,差异有统计学意义(P<0.05),ISS组、PGHD组的25-(OH)D、IGF-1、IGFBP-3水平比较无差异(P>0.05),25-(OH)D、IGF-1、IGFBP-3水平与矮小症均呈负相关,差异有统计学意义(P<0.05)。结论儿童矮小症与25-(OH)D、IGF-1、IGFBP-3之间关系密切,对矮小症的诊断和综合评价具有重要意义,可作为该病的确诊指标之一。 展开更多
关键词 儿童矮小症 25羟基维生素d 胰岛素样生长因子-1 胰岛素生长因子结合蛋白-3
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3D Web Reconstruction of a Fibrous Filter Using Sequential Multi-Focus Images
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作者 Lingjie Yu Guanlin Wang +1 位作者 Chao Zhi Bugao Xu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2019年第5期365-372,共8页
A fibrous filtering material is a kind of fiber assembly whose structure exhibits a three-dimensional(3D)network with dense microscopic open channels.The geometrical/morphological attributes,such as orientations,curva... A fibrous filtering material is a kind of fiber assembly whose structure exhibits a three-dimensional(3D)network with dense microscopic open channels.The geometrical/morphological attributes,such as orientations,curvatures and compactness,of fibers in the network is the key to the filtration performance of the material.However,most of the previous studies were based on materials’2D micro-images,which were unable to accurately measure these important 3D features of a filter’s structure.In this paper,we present an imaging method to reconstruct the 3D structure of a fibrous filter from its optical microscopic images.Firstly,a series of images of the fiber assembly were captured at different depth layers as the stage moved vertically.Then a fusion image was established by extracting fiber edges from each layered image.Thirdly,the 3D coordinates of the fiber edges were determined using the sharpness/clarity of each edge pixel in the layered images.Finally,the 3D structure the fiber system was reconstructed through distance transformation based on the locations of fiber edges. 展开更多
关键词 3d reconstruction SHARPNESS EVALUATION FIBER WEB
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