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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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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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Three-dimensional reconstruction of industrial parts from a single image
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作者 Zhenxing Xu Aizeng Wang +1 位作者 Fei Hou Gang Zhao 《Visual Computing for Industry,Biomedicine,and Art》 2024年第1期340-351,共12页
This study proposes an image-based three-dimensional(3D)vector reconstruction of industrial parts that can gener-ate non-uniform rational B-splines(NURBS)surfaces with high fidelity and flexibility.The contributions o... This study proposes an image-based three-dimensional(3D)vector reconstruction of industrial parts that can gener-ate non-uniform rational B-splines(NURBS)surfaces with high fidelity and flexibility.The contributions of this study include three parts:first,a dataset of two-dimensional images is constructed for typical industrial parts,including hex-agonal head bolts,cylindrical gears,shoulder rings,hexagonal nuts,and cylindrical roller bearings;second,a deep learning algorithm is developed for parameter extraction of 3D industrial parts,which can determine the final 3D parameters and pose information of the reconstructed model using two new nets,CAD-ClassNet and CAD-ReconNet;and finally,a 3D vector shape reconstruction of mechanical parts is presented to generate NURBS from the obtained shape parameters.The final reconstructed models show that the proposed approach is highly accurate,efficient,and practical. 展开更多
关键词 Three-dimensional reconstruction Non-uniform rational B-splines Industrial parts Deep learning
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Assessment of Gastric Cancer: Value of Two-phase Multidetector-row Spiral CT Three-dimensional Reconstruction Technique 被引量:4
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作者 李震 胡道予 +2 位作者 肖明 张进华 宋金梅 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第6期365-368,共4页
Abstract Objective: To evaluate the diagnostic value of two-phase multidetector-row spiral CT threedimensional reconstruction technique in TNM staging of gastric cancer. Methods: In 29 patients with gastric carcinom... Abstract Objective: To evaluate the diagnostic value of two-phase multidetector-row spiral CT threedimensional reconstruction technique in TNM staging of gastric cancer. Methods: In 29 patients with gastric carcinoma pathologically conformed, plan scans were done firstly. Two-phase spiral CT was performed within one breathhold each. Distension of the stomach was achieved by intravenous application of anisodamine and effervescent granules. After bolus injection of contrast medium, scanning was performed in the arterial and venous phase, and the source images were thin reconstructed. The stomach to three-dimension analysis was constructed by volume rendering (VR) multiplanaz volume reconstruction (MPVR), shaded surface display (SSD) and CT virtual gastroscopy (CTVG) technique. In combination with the sources images, gastric tumour invasion and lymph node metastasis was assessed, and TNM staging was performed. Results: In 29 cases of gastric carcinoma, the sensitivity and specificity of two-phase multidetector-row spiral CT three-dimensional reconstruction technique in T1, T2, T3 and Ta staging, the sensitivity and specificity was 50% and 50%, 87.5% and 77.8%, 83.3% and 76.9% and 100% and 80% respectively. For the N staging, the sensitivity and specificity in No, N1, and N2 N3 was 83.3% and 71.4%, 87.5% and 77.8% and 81.8% and 75% respectively. The sensitivity and the specificity for M1 staging was 100%. Conclusion: The reconstruction technique in combination with 16-slices spiral-CT can perform TNM staging well and effectively guide the choice of the surgical procedures for gastric cancer. 展开更多
关键词 SPIRAL-CT gastric carcinoma three-dimensional reconstruction
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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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Deciphering Water Oxidation Catalysts:The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion
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作者 Li An Jianyi Li +7 位作者 Yuanmiao Sun Jiamin Zhu Justin Zhu Yeow Seow Hong Zhang Nan Zhang Pinxian Xi Zhichuan J.Xu Chun‑Hua Yan 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期340-354,共15页
Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has ... Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity enhancement.Here,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is reported.The substituting Fe content influences both current change tendency and surface reconstruction degree.LaNi_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)series.The reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based catalysts.Besides,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term stability.Furthermore,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction degree.The effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface reconstruction.This finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation. 展开更多
关键词 Oxygen evolution reaction Perovskite oxides DOPING Activation and reconstruction
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Navigating medial patellotibial ligament reconstruction:Clinical perspectives and surgical strategies
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作者 Juan Pablo Zicaro Ignacio Garcia-Mansilla 《World Journal of Clinical Cases》 SCIE 2025年第1期6-10,共5页
The surgical approach for patellar instability usually refers to reconstruction of the medial patellofemoral ligament associated with an osteotomy of the tibial tuberosity or a trochleoplasty when required.The medial ... The surgical approach for patellar instability usually refers to reconstruction of the medial patellofemoral ligament associated with an osteotomy of the tibial tuberosity or a trochleoplasty when required.The medial patellotibial ligament and the medial patellomeniscal ligament are secondary stabilizers of the patella.Despite this,both the medial patellotibial and patellofemoral ligaments aid in patellar rotation and tilt when the knee is flexed beyond 45°.The medial patellotibial ligament plays a particularly important role in the final stages of stretching in extension and between 40 degrees to 90 degrees of flexion.The clinical relevance and surgical indications for medial patellotibial ligament reconstruction associated with medial patellofemoral ligament reconstruction are still controversial.This editorial explores the surgical indications and clinical results for medial patellotibial ligament reconstruction to improve readers’understanding of this technique,especially because reported clinical outcomes have remained sparse. 展开更多
关键词 Medial patellotibial ligament Patellar instability reconstruction SURGICAL
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Reviews on Post-earthquake Reconstruction of Qiang Culture: Three-dimensional Pattern
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作者 许虹 《Journal of Landscape Research》 2011年第9期11-13,18,共4页
Through the introduction of disaster situation of Qiang Culture after Wenchuan Earthquake, the paper emphasized that carriers of Qiang Culture had been seriously damaged, the inheritance of Qiang Culture had been affe... Through the introduction of disaster situation of Qiang Culture after Wenchuan Earthquake, the paper emphasized that carriers of Qiang Culture had been seriously damaged, the inheritance of Qiang Culture had been affected, and the environment for Qiang Culture was difficult to recover. It highlighted that three-dimensional reconstruction of Qiang Culture should stress the core task and timely and effectively rescue endangered cultural heritages of Qiang Nationality from the perspectives of material and spiritual life. It had explained focuses of three-dimensional pattern construction in detail. In terms of spatial reconstruction, it should reconstruct native culture and history while material culture was constructed, and reconstruct Qiang culture highland by depending on aborigines; in terms of cluster reconstruction, it should give support to large tourism enterprises and perfect tourism chain; in terms of ecological reconstruction, it should enhance construction and demonstration of "ecological protection pilot area of Qiang culture"; in terms of development reconstruction, it should realize coordinated unity between protection and development according to classification protection, characteristic protection and key protection, so as to form the virtuous circle of post-disaster recovery protection and sustainable development. 展开更多
关键词 Qiang CULTURE POST-EARTHQUAKE reconstruction THREE-dimensional PATTERN
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Exploration of Gas‑Dependent Self‑Adaptive Reconstruction Behavior of Cu_(2)O for Electrochemical CO_(2) Conversion to Multi‑Carbon Products
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作者 Chaoran Zhang Yichuan Gu +7 位作者 Qu Jiang Ziyang Sheng Ruohan Feng Sihong Wang Haoyue Zhang Qianqing Xu Zijian Yuan Fang Song 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期280-296,共17页
Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially understood.Here,we report that CO_(2)acc... Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially understood.Here,we report that CO_(2)accessibility results in a universal self-adaptive structural reconstruction from Cu_(2)O to Cu@CuxO composites,ending with feeding gas-dependent microstructures and catalytic performances.The CO_(2)-rich atmosphere favors reconstruction for CO_(2)RR,whereas the CO_(2)-deficient one prefers that for hydrogen evolution reaction.With the assistance of spectroscopic analysis and theoretical calculations,we uncover a CO_(2)-induced passivation behavior by identifying a reductionresistant but catalytic active Cu(I)-rich amorphous layer stabilized by*CO intermediates.Additionally,we find extra CO production is indispensable for the robust production of C2H4.An inverse correlation between durability and FECO/FEC2H4 is disclosed,suggesting that the selfstabilization process involving the absorption of*CO intermediates on Cu(I)sites is essential for durable electrolysis.Guided by this insight,we design hollow Cu_(2)O nanospheres for durable and selective CO_(2)RR electrolysis in producing C2H4.Our work recognizes the previously overlooked passivation reconstruction and self-stabilizing behavior and highlights the critical role of the local atmosphere in modulating reconstruction and catalytic processes. 展开更多
关键词 CO_(2)reduction reaction ELECTROCATALYSTS Cu_(2)O reconstruction Self-adaptive electrocatalysis
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Magnamosis for rectal reconstruction in canines
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作者 Shi-Qi Liu Hong-Ke Zhang +3 位作者 Yi Lv Xiang-Hua Xu Yu-Feng Li Dong-Wen Quan 《World Journal of Gastrointestinal Surgery》 2025年第2期227-236,共10页
BACKGROUND The magnamosis,a minimal invasive,suture-free procedure,has been used for digestive tract or vessel reconstruction,such as gastrointestinal anastomosis,bilioenteric anastomosis,and coronary artery bypass.Al... BACKGROUND The magnamosis,a minimal invasive,suture-free procedure,has been used for digestive tract or vessel reconstruction,such as gastrointestinal anastomosis,bilioenteric anastomosis,and coronary artery bypass.Although some case reports have demonstrated the potential of magnamosis for the treatment of congenital rectal atresia(RA),they cannot provide strong evidence for its widespread application.AIM To assess the feasibility and safety of magnamosis in treating RA in dogs as compared to suturing anastomosis.The findings of this study can be beneficial in guiding the clinical application of magnamosis.METHODS Thirty-six dogs were randomly assigned to the magnamosis group(n=18)and the suturing anastomosis group(n=18).The rectum was freed laparoscopically in all dogs.In the magnamosis group,rectal anastomosis was performed using a pair of magnetic rings,while the suturing anastomosis group underwent a straight-sighted end-to-end rectal anastomosis with 4-0 absorbable sutures.The anastomosis time was recorded,and abdominal plain film examination was performed to locate the magnets until they were expelled postoperatively.Specimens of the anastomosis were evaluated at one month,three months,and six months after surgery.RESULTS The mean time for rectal anastomosis was significantly shorter in the magnamosis group(12.22±2.78 minutes)than the suturing anastomosis group(18.11±1.68 minutes).There was one incidence of anastomotic bleeding in the suturing anastomosis group,whereas no complication was recorded in the magnamosis group.The magnets were discharged post-surgery in 7.17±1.30 days in all the dogs.The histopathological examination revealed a smoother healing of anastomotic mucosa in the magnamosis group as compared to that in the suturing anastomosis group.Moreover,the fiber alignment was also more natural in the magnamosis group with minimal inflammation.CONCLUSION Rectal reconstruction using magnamosis is a feasible,safe,and effective alternative to suturing anastomosis in dogs,with the added benefit of faster and more natural healing of the anastomosis. 展开更多
关键词 Rectal reconstruction CANINES Magnamosis DOGS
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Action Based Approach to Archaeological Reconstruction Projects: Case of the Karnak Temple in Egypt
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作者 Anis Semlali 《Journal of Civil Engineering and Architecture》 2025年第1期27-35,共9页
The proposed paper deals with a numerical approach that could better assist the archaeologist in the archaeological reconstruction projects.The goal of our research is to explore and study the use of computerized tool... The proposed paper deals with a numerical approach that could better assist the archaeologist in the archaeological reconstruction projects.The goal of our research is to explore and study the use of computerized tools in archaeological reconstruction projects of monumental architecture in order to propose new ways in which such technology can be used. 展开更多
关键词 Architectural heritage archaeological reconstruction process and actions action-based modeling architecture and complexity
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From Imperfection to Perfection: Advanced 3D Facial Reconstruction Using MICA Models and Self-Supervision Learning
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作者 Thinh D.Le Duong Q.Nguyen +1 位作者 Phuong D.Nguyen H.Nguyen-Xuan 《Computer Modeling in Engineering & Sciences》 2025年第2期1459-1479,共21页
Research on reconstructing imperfect faces is a challenging task.In this study,we explore a data-driven approach using a pre-trained MICA(MetrIC fAce)model combined with 3D printing to address this challenge.We propos... Research on reconstructing imperfect faces is a challenging task.In this study,we explore a data-driven approach using a pre-trained MICA(MetrIC fAce)model combined with 3D printing to address this challenge.We propose a training strategy that utilizes the pre-trained MICA model and self-supervised learning techniques to improve accuracy and reduce the time needed for 3D facial structure reconstruction.Our results demonstrate high accuracy,evaluated by the geometric loss function and various statistical measures.To showcase the effectiveness of the approach,we used 3D printing to create a model that covers facial wounds.The findings indicate that our method produces a model that fits well and achieves comprehensive 3D facial reconstruction.This technique has the potential to aid doctors in treating patients with facial injuries. 展开更多
关键词 3D face reconstruction self-supervised learning face defect 3D printed prototypes
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Novel surgical approach-cadaveric inferior vena cava graft reconstruction following leiomyosarcoma resection:A case report
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作者 Hadeel A AlOmran Bayan AlMatar +3 位作者 Mohammed AlMonsained Shoukat Bojal Hammam Momani Mohammed S AlQahtani 《World Journal of Gastrointestinal Surgery》 2025年第2期285-290,共6页
BACKGROUND Inferior vena cava(IVC)leiomyosarcomas are rare and aggressive tumors.Complete cure depends on achieving R0 resection,which often requires circumferential resection and reconstruction.Synthetic grafts have ... BACKGROUND Inferior vena cava(IVC)leiomyosarcomas are rare and aggressive tumors.Complete cure depends on achieving R0 resection,which often requires circumferential resection and reconstruction.Synthetic grafts have traditionally been used when venous continuity must be restored.However,the use of cadaveric IVC grafts for reconstruction has not been widely reported.CASE SUMMARY Herein,we present the case of a 64-year-old woman diagnosed with an intrahepatic IVC leiomyosarcoma with local invasion.The patient responded favorably to chemotherapy and subsequently underwent an en bloc right hepatectomy,retrohepatic IVC resection,and reconstruction with an interpositional cadaveric IVC graft.Serial imaging follow-ups until 2 years after the operation showed persistent patency of the graft and no graft-related complications.CONCLUSION Cadaveric IVC grafts are an alternative to synthetic grafts for reconstruction,with acceptable outcomes.Larger,long-term studies are necessary to validate these findings. 展开更多
关键词 Inferior vena cava leiomyosarcoma Vascular sarcoma Vascular reconstruction Venous cadaveric graft Case report
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Emergent 3×3 charge order on the Cs reconstruction of kagome superconductor CsV3Sb5
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作者 Xianghe Han Zhongyi Cao +4 位作者 Zihao Huang Zhen Zhao Haitao Yang Hui Chen Hong-Jun Gao 《Chinese Physics B》 2025年第1期46-51,共6页
The alkali adatoms with controlled coverage on the surface have been demonstrated to effectively tune the surface band of quantum materials through in situ electron doping.However,the interplay of orderly arranged alk... The alkali adatoms with controlled coverage on the surface have been demonstrated to effectively tune the surface band of quantum materials through in situ electron doping.However,the interplay of orderly arranged alkali adatoms with the surface states of quantum materials remains unexplored.Here,by using low-temperature scanning tunneling microscopy/spectroscopy(STM/S),we observed the emergent 3×3 super modulation of electronic states on the√3×√3R30°(R3)Cs ordered surface of kagome superconductor CsV3Sb5.The nondispersive 3×3 superlattice at R3 ordered surface shows contrast inversion in positive and negative differential conductance maps,indicating a charge order origin.The 3×3 charge order is suppressed with increasing temperature and undetectable at a critical temperature of~62 K.Furthermore,in the Ta substituted sample CsV_(2.6)Ta_(0.4)Sb_(5),where long-range 2×2×2 charge density wave is significantly suppressed,the 3×3 charge order on the R3 ordered surface becomes blurred and much weaker than that in the undoped sample.It indicates that the 3×3 charge order on the R3 ordered surface is directly correlated to the bulk charge density waves in CsV_(3)Sb_(5.O)ur work provides a new platform for understanding and manipulating the cascade of charge orders in kagome superconductors. 展开更多
关键词 CsV3Sb5 surface reconstruction alkali atoms charge order scanning tunneling microscope/spectroscopy
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Automatic three-dimensional reconstruction based on four-view stereo vision using checkerboard pattern 被引量:5
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作者 XIONG Jie ZHONG Si-dong +1 位作者 LIU Yong TU Li-fen 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1063-1072,共10页
An automatic three-dimensional(3D) reconstruction method based on four-view stereo vision using checkerboard pattern is presented. Mismatches easily exist in traditional binocular stereo matching due to the repeatable... An automatic three-dimensional(3D) reconstruction method based on four-view stereo vision using checkerboard pattern is presented. Mismatches easily exist in traditional binocular stereo matching due to the repeatable or similar features of binocular images. In order to reduce the probability of mismatching and improve the measure precision, a four-camera measurement system which can add extra matching constraints and offer multiple measurements is applied in this work. Moreover, a series of different checkerboard patterns are projected onto the object to obtain dense feature points and remove mismatched points. Finally, the 3D model is generated by performing Delaunay triangulation and texture mapping on the point cloud obtained by four-view matching. This method was tested on the 3D reconstruction of a terracotta soldier sculpture and the Buddhas in the Mogao Grottoes. Their point clouds without mismatched points were obtained and less processing time was consumed in most cases relative to binocular matching. These good reconstructed models show the effectiveness of the method. 展开更多
关键词 three-dimensional reconstruction four-view STEREO VISION CHECKERBOARD pattern DENSE point
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Disagreement in middle ear volume estimation between tympanometry and three-dimensional volume reconstruction in the context of tympanic membrane perforation 被引量:2
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作者 David J.Carpenter Debara L.Tucci +1 位作者 David M.Kaylie Dennis O.Frank-Ito 《Journal of Otology》 CSCD 2017年第2期74-79,共6页
Introduction: Middle ear volume(MEV) is a clinically relevant parameter across middle ear diseases. MEV values between these techniques have never before been tested for agreement in ears with perforated tympanic memb... Introduction: Middle ear volume(MEV) is a clinically relevant parameter across middle ear diseases. MEV values between these techniques have never before been tested for agreement in ears with perforated tympanic membranes(TMs).Methods: Middle ears were identified from 36 patients ranging 18-89 years of age with TM perforations who underwent tympanometry and temporal bone computed tomography(CT) between 2005 and 2015. MEVs calculated by both tympanometry and three-dimensional volume reconstruction(3DVR) were analyzed for agreement using Bland Altman plots. The differences between tympanometric and 3DVR MEV values for each given middle ear were characterized across MEV quartiles(1= smallest; 4= largest) and across increasing states of middle ear disease using Kruskale Wallis and Wilcoxon testing with Bonferroni correction.Results: Bland Altman plots demonstrated significant disagreement between MEV measurement techniques. Differences between tympanometric(T) and 3DVR MEV values were significantly greater with increasing average(i.e.(Tt3DVR)/2)) MEV per linear regression(p < 0.0001). Significance was demonstrated between fourth and first average MEV quartiles(p= 0.0024), fourth and second quartiles(p= 0.0024), third and first quartiles(p= 0.0048), and third and second quartiles(p= 0.048). Absolute MEV difference was not significantly different across varying states of middle ear disease(p= 0.44).Conclusion: Statistically and clinically significant disagreement was demonstrated between tympanometric and 3DVR MEV values. Studies that vary in MEV estimation techniques may be expected to demonstrate significantly different results. These preliminary results suggest that clinicians should endeavor to seek further confirmation when interpreting high tympanometric MEV values. 展开更多
关键词 Middle EAR VOLUME TYMPANOMETRY THREE-dimensional VOLUME reconstruction Tympanic membrane PERFORATION
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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 Reconstruction of Geological Solids Based on Section Topology Reasoning 被引量:13
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作者 HE Zhenwen WU Chonglong +1 位作者 TIAN Yiping MAO Xiaoping 《Geo-Spatial Information Science》 2008年第3期201-208,共8页
In order to solve the dynamic reconstruction and local updating problem of three-dimensional geological solids, topology reasoning is used for three-dimensional geological modeling. This can advance the level of the c... In order to solve the dynamic reconstruction and local updating problem of three-dimensional geological solids, topology reasoning is used for three-dimensional geological modeling. This can advance the level of the corresponding section automation in implementing the 3D geological solid dynamical reconstruction by the construction of and reasoning on topology on the 3D curved surface. This method has been successfully used in the Nanjing city geological modeling and the Zijin gold mine modeling. The results prove that this method adapts to coplanar section and noncoplanar section data, and improves the efficiency of 3D geological modeling. 展开更多
关键词 geological section topology reasoning 3D geological solid reconstruction
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Three-dimensional reconstruction of human spinal cord based on histological serial sections 被引量:1
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作者 Guangming Lü Huiqun Wu +3 位作者 Lemin Tang Xiao Han Dafeng Ji Xiaosong Gu 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第7期697-700,共4页
BACKGROUND: It is not possible to reconstruct the inner structure of the spinal cord, such as gray matter and spinal tracts, from the Visual Human Project database or CT and MRI databases, due to low image resolution... BACKGROUND: It is not possible to reconstruct the inner structure of the spinal cord, such as gray matter and spinal tracts, from the Visual Human Project database or CT and MRI databases, due to low image resolution and contrast in macrosection images. OBJECTIVE: To explore a semi-automatic computerized three-dimensional (3D) reconstruction of human spinal cord based on histological serial sections, in order to solve issues such as low contrast. DESIGN, TIME AND SETTING: An experimental study combining serial section techniques and 3D reconstruction, performed in the laboratory of Human Anatomy and Histoembryology at the Medical School of Nantong University during January to April 2008. SETTING: Department of Anatomy, Institute of Neurobiology, Jiangsu Province Key Laboratory of Neural Regeneration, Laboratory of Image Engineering. MATERIALS: A human lumbar spinal cord segment from fresh autopsy material of an adult male. METHODS: After 4% paraformaldehyde fixation for three days, serial sections of the lumbar spinal cord were cut on a Leica cryostat and mounted on slides in sequence, with eight sections aligned separately on each slide. All sections were stained with Luxol Fast Blue to reveal myelin sheaths. After gradient dehydration and clearing, the stained slides were coverslipped. Sections were observed and images recorded under a light microscope using a digital camera. Six images were acquired at x25 magnification and automatically stitched into a complete section image. After all serial images were obtained, 96 complete serial images of the human lumbar cord segment were automatically processed with "Curves", "Autocontrast", "Gray scale 8 bit", "Invert", "Image resize to 50%" steps using Photoshop 7.0 software. All images were added in order into 3D-DOCTOR 4.0 software as a stack, where serial images were automatically realigned with neighboring images and semi-automatically segmented for white matter and gray matter. Finally, simple surface and volume reconstruction were completed on a personal computer. The reconstructed human lumbar spinal cord segment was interactively observed, cut, and measured. MAIN OUTCOME MEASURES: The reconstructed human lumbar spinal cord segment. RESULTS: Compared with serial images obtained from other image modalities, such as CT, MRI, and macrosections from The Visual Human Project database, the Luxol Fast Blue stained histological serial section images exhibited higher resolution and contrast between gray and white matter. Image processing and 3D reconstruction steps were semi-automatically performed with related software. The 3D reconstructed human lumbar cord segment were observed, cut, and measured on a PC. CONCLUSION: A semi-automatically computerized method, based on histological serial sections, is an effective way to 3D-reconstruct the human spinal cord. 展开更多
关键词 Luxol Fast Blue reconstruction serial sections surface THREE-dimensional visible human project VOLUME
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Three-Dimensional Reconstruction of Welding Pool Surface by Binocular Vision 被引量:8
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作者 Zunan Gu Ji Chen Chuansong Wu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第3期272-284,共13页
Current research of binocular vision systems mainly need to resolve the camera’s intrinsic parameters before the reconstruction of three-dimensional(3D)objects.The classical Zhang’calibration is hardly to calculate ... Current research of binocular vision systems mainly need to resolve the camera’s intrinsic parameters before the reconstruction of three-dimensional(3D)objects.The classical Zhang’calibration is hardly to calculate all errors caused by perspective distortion and lens distortion.Also,the image-matching algorithm of the binocular vision system still needs to be improved to accelerate the reconstruction speed of welding pool surfaces.In this paper,a preset coordinate system was utilized for camera calibration instead of Zhang’calibration.The binocular vision system was modified to capture images of welding pool surfaces by suppressing the strong arc interference during gas metal arc welding.Combining and improving the algorithms of speeded up robust features,binary robust invariant scalable keypoints,and KAZE,the feature information of points(i.e.,RGB values,pixel coordinates)was extracted as the feature vector of the welding pool surface.Based on the characteristics of the welding images,a mismatch-elimination algorithm was developed to increase the accuracy of image-matching algorithms.The world coordinates of matching feature points were calculated to reconstruct the 3D shape of the welding pool surface.The effectiveness and accuracy of the reconstruction of welding pool surfaces were verified by experimental results.This research proposes the development of binocular vision algorithms that can reconstruct the surface of welding pools accurately to realize intelligent welding control systems in the future. 展开更多
关键词 Surface reconstruction Welding pool Binocular imaging Gas metal arc welding Feature points matching
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