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In-situ three-dimensional visualization of dynamic tension deformation in ferrite stainless steels
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作者 ZHANG Zhixia BI Hongyun LI Xin 《Baosteel Technical Research》 CAS 2013年第4期56-61,共6页
An improved three-dimensional (3-D) experimental visualization methodology is presented tor evaluating the fracture mechanisms of ferritic stainless steels by in-situ tensile testing with an environmental scanning e... An improved three-dimensional (3-D) experimental visualization methodology is presented tor evaluating the fracture mechanisms of ferritic stainless steels by in-situ tensile testing with an environmental scanning electron microscope (ESEM). The samples were machined with a radial notched shape and a sloped surface. Both planar surface deformation and sloping surface deformation-induced microvoids were observed during dynamic tension experiments, where a greater amount of information could be obtained from the sloping surface. The results showed that microvoids formed at the grain boundaries of highly elongated large grains. The microvoids nucleated in the severely deformed regions grew nearly parallel to the tensile axis, predominantly along the grain boundaries. The microvoids nucleated at the interface of particles and the matrix did not propagate due to the high plasticity of the matrix. The large microvoids propagated and showed a zigzag shape along the grain boundaries,seemingly a consequence of the fracture of the slip bands caused by dislocation pile-ups. The final failure took place due to the reduction of the load-beating area. 展开更多
关键词 three-dimensional (3-D) visualization MICROVOIDS in-situ dynamic tensile testing ferritic stainless steels
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Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions
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作者 Chentong GAO Huiyu SUN +1 位作者 Jianping GU W.M.HUANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期123-138,共16页
Currently,there are a limited number of dynamic models available for braided composite plates with large overall motions,despite the incorporation of three-dimensional(3D)braided composites into rotating blade compone... Currently,there are a limited number of dynamic models available for braided composite plates with large overall motions,despite the incorporation of three-dimensional(3D)braided composites into rotating blade components.In this paper,a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established.Based on Kirchhoff's plate assumptions,the displacement variables of the plate are expressed.By incorporating the braiding directions into the constitutive equation of the braided composites,the dynamic model of the plate considering braiding directions is obtained.The effects of the speeds,braiding directions,and braided angles on the responses of the plate with fixed-axis rotation and translational motion,respectively,are investigated.This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions.It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications. 展开更多
关键词 three-dimensional(3D)braided composite braiding direction composite thin plate large overall motion dynamic model
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Hybrid CO_(2) thermal system for post-steam heavy oil recovery:Insights from microscopic visualization experiments and molecular dynamics simulations
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作者 Ning Lu Xiaohu Dong +4 位作者 Haitao Wang Huiqing Liu Zhangxin Chen Yu Li Deshang Zeng 《Energy Geoscience》 2025年第2期233-248,共16页
The hybrid CO_(2) thermal technique has achieved considerable success globally in extracting residual heavy oil from reserves following a long-term steam stimulation process.Using microscopic visualization experiments... The hybrid CO_(2) thermal technique has achieved considerable success globally in extracting residual heavy oil from reserves following a long-term steam stimulation process.Using microscopic visualization experiments and molecular dynamics(MD)simulations,this study investigates the microscopic enhanced oil recovery(EOR)mechanisms underlying residual oil removal using hybrid CO_(2) thermal systems.Based on the experimental models for the occurrence of heavy oil,this study evaluates the performance of hybrid CO_(2) thermal systems under various conditions using MD simulations.The results demonstrate that introducing CO_(2) molecules into heavy oil can effectively penetrate and decompose dense aggregates that are originally formed on hydrophobic surfaces.A stable miscible hybrid CO_(2) thermal system,with a high effective distribution ratio of CO_(2),proficiently reduces the interaction energies between heavy oil and rock surfaces,as well as within heavy oil.A visualization analysis of the interactions reveals that strong van der Waals(vdW)attractions occur between CO_(2) and heavy oil molecules,effectively promoting the decomposition and swelling of heavy oil.This unlocks the residual oil on the hydrophobic surfaces.Considering the impacts of temperature and CO_(2) concentration,an optimal gas-to-steam injection ratio(here,the CO_(2):steam ratio)ranging between 1:6 and 1:9 is recommended.This study examines the microscopic mechanisms underlying the hybrid CO_(2) thermal technique at a molecular scale,providing a significant theoretical guide for its expanded application in EOR. 展开更多
关键词 Heavy oil Hybrid CO_(2)thermal system Microscopic visualization experiment Molecular dynamics simulation Microscopic mechanism
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Integration system research and development for three-dimensional laser scanning information visualization in goaf 被引量:2
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作者 罗周全 黄俊杰 +2 位作者 罗贞焱 汪伟 秦亚光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1985-1994,共10页
An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, clo... An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable. 展开更多
关键词 GOAF laser scanning visualization integration system 1 Introduction The goaf formed through underground mining of mineral resources is one of the main disaster sources threatening mine safety production [1 2]. Effective implementation of goaf detection and accurate acquisition of its spatial characteristics including the three-dimensional morphology the spatial position as well as the actual boundary and volume are important basis to analyze predict and control disasters caused by goaf. In recent years three-dimensional laser scanning technology has been effectively applied in goaf detection [3 4]. Large quantities of point cloud data that are acquired for goaf by means of the three-dimensional laser scanning system are processed relying on relevant engineering software to generate a three-dimensional model for goaf. Then a general modeling analysis and processing instrument are introduced to perform subsequent three-dimensional analysis and calculation [5 6]. Moreover related development is also carried out in fields such as three-dimensional detection and visualization of hazardous goaf detection and analysis of unstable failures in goaf extraction boundary acquisition in stope visualized computation of damage index aided design for pillar recovery and three-dimensional detection
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DKP-SLAM:A Visual SLAM for Dynamic Indoor Scenes Based on Object Detection and Region Probability
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作者 Menglin Yin Yong Qin Jiansheng Peng 《Computers, Materials & Continua》 SCIE EI 2025年第1期1329-1347,共19页
In dynamic scenarios,visual simultaneous localization and mapping(SLAM)algorithms often incorrectly incorporate dynamic points during camera pose computation,leading to reduced accuracy and robustness.This paper prese... In dynamic scenarios,visual simultaneous localization and mapping(SLAM)algorithms often incorrectly incorporate dynamic points during camera pose computation,leading to reduced accuracy and robustness.This paper presents a dynamic SLAM algorithm that leverages object detection and regional dynamic probability.Firstly,a parallel thread employs the YOLOX object detectionmodel to gather 2D semantic information and compensate for missed detections.Next,an improved K-means++clustering algorithm clusters bounding box regions,adaptively determining the threshold for extracting dynamic object contours as dynamic points change.This process divides the image into low dynamic,suspicious dynamic,and high dynamic regions.In the tracking thread,the dynamic point removal module assigns dynamic probability weights to the feature points in these regions.Combined with geometric methods,it detects and removes the dynamic points.The final evaluation on the public TUM RGB-D dataset shows that the proposed dynamic SLAM algorithm surpasses most existing SLAM algorithms,providing better pose estimation accuracy and robustness in dynamic environments. 展开更多
关键词 visual SLAM dynamic scene YOLOX K-means++clustering dynamic probability
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YGC-SLAM:A visual SLAM based on improved YOLOv5 and geometric constraints for dynamic indoor environments
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作者 Juncheng ZHANG Fuyang KE +2 位作者 Qinqin TANG Wenming YU Ming ZHANG 《虚拟现实与智能硬件(中英文)》 2025年第1期62-82,共21页
Background As visual simultaneous localization and mapping(SLAM)is primarily based on the assumption of a static scene,the presence of dynamic objects in the frame causes problems such as a deterioration of system rob... Background As visual simultaneous localization and mapping(SLAM)is primarily based on the assumption of a static scene,the presence of dynamic objects in the frame causes problems such as a deterioration of system robustness and inaccurate position estimation.In this study,we propose a YGC-SLAM for indoor dynamic environments based on the ORB-SLAM2 framework combined with semantic and geometric constraints to improve the positioning accuracy and robustness of the system.Methods First,the recognition accuracy of YOLOv5 was improved by introducing the convolution block attention model and the improved EIOU loss function,whereby the prediction frame converges quickly for better detection.The improved YOLOv5 was then added to the tracking thread for dynamic target detection to eliminate dynamic points.Subsequently,multi-view geometric constraints were used for re-judging to further eliminate dynamic points while enabling more useful feature points to be retained and preventing the semantic approach from over-eliminating feature points,causing a failure of map building.The K-means clustering algorithm was used to accelerate this process and quickly calculate and determine the motion state of each cluster of pixel points.Finally,a strategy for drawing keyframes with de-redundancy was implemented to construct a clear 3D dense static point-cloud map.Results Through testing on TUM dataset and a real environment,the experimental results show that our algorithm reduces the absolute trajectory error by 98.22%and the relative trajectory error by 97.98%compared with the original ORBSLAM2,which is more accurate and has better real-time performance than similar algorithms,such as DynaSLAM and DS-SLAM.Conclusions The YGC-SLAM proposed in this study can effectively eliminate the adverse effects of dynamic objects,and the system can better complete positioning and map building tasks in complex environments. 展开更多
关键词 visual SLAM dynamic SLAM Target detection Geometric constraints
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PPS-SLAM: Dynamic Visual SLAM with a Precise Pruning Strategy
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作者 Jiansheng Peng Wei Qian Hongyu Zhang 《Computers, Materials & Continua》 2025年第2期2849-2868,共20页
Dynamic visual SLAM (Simultaneous Localization and Mapping) is an important research area, but existing methods struggle to balance real-time performance and accuracy in removing dynamic feature points, especially whe... Dynamic visual SLAM (Simultaneous Localization and Mapping) is an important research area, but existing methods struggle to balance real-time performance and accuracy in removing dynamic feature points, especially when semantic information is missing. This paper presents a novel dynamic SLAM system that uses optical flow tracking and epipolar geometry to identify dynamic feature points and applies a regional dynamic probability method to improve removal accuracy. We developed two innovative algorithms for precise pruning of dynamic regions: first, using optical flow and epipolar geometry to identify and prune dynamic areas while preserving static regions on stationary dynamic objects to optimize tracking performance;second, propagating dynamic probabilities across frames to mitigate the impact of semantic information loss in some frames. Experiments show that our system significantly reduces trajectory and pose errors in dynamic scenes, achieving dynamic feature point removal accuracy close to that of semantic segmentation methods, while maintaining high real-time performance. Our system performs exceptionally well in highly dynamic environments, especially where complex dynamic objects are present, demonstrating its advantage in handling dynamic scenarios. The experiments also show that while traditional methods may fail in tracking when semantic information is lost, our approach effectively reduces the misidentification of dynamic regions caused by such loss, thus improving system robustness and accuracy. 展开更多
关键词 visual SLAM dynamic SLAM YOLOv8
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Correction:Neural Dynamics of Visual Stream Interactions During Memory-Guided Actions Investigated by Intracranial EEG
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作者 Sofiia Moraresku Jiri Hammer +6 位作者 Vasileios Dimakopoulos Michaela Kajsova Radek Janca Petr Jezdik Adam Kalina Petr Marusic Kamil Vlcek 《Neuroscience Bulletin》 2025年第9期1709-1709,共1页
Correction to:Neuroscience Bulletin https://doi.org/10.1007/s12264-025-01371-x In this article the affiliation"Department of Circuit Theory,Faculty of Electrical Engineering,Czech Technical University in Prague,M... Correction to:Neuroscience Bulletin https://doi.org/10.1007/s12264-025-01371-x In this article the affiliation"Department of Circuit Theory,Faculty of Electrical Engineering,Czech Technical University in Prague,Member of the Epilepsy Research Centre Prague-EpiReC Consortium,Prague,Czechia"should only be assigned to Radek Janca and Petr Jezdik.It is removed from the authors:Jiri Hammer,Michaela Kajsova,Adam Kalina,Petr Marusic,and Kamil Vlcek. 展开更多
关键词 visual stream interactions memory guided actions neural dynamics neuroscience intracranial EEG
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Current trends in three-dimensional visualization and real-time navigation as well as robot-assisted technologies in hepatobiliary surgery 被引量:14
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作者 Yun Wang Di Cao +3 位作者 Si-Lin Chen Yu-Mei Li Yun-Wen Zheng Nobuhiro Ohkohchi 《World Journal of Gastrointestinal Surgery》 SCIE 2021年第9期904-922,共19页
With the continuous development of digital medicine,minimally invasive precision and safety have become the primary development trends in hepatobiliary surgery.Due to the specificity and complexity of hepatobiliary su... With the continuous development of digital medicine,minimally invasive precision and safety have become the primary development trends in hepatobiliary surgery.Due to the specificity and complexity of hepatobiliary surgery,traditional preoperative imaging techniques such as computed tomography and magnetic resonance imaging cannot meet the need for identification of fine anatomical regions.Imaging-based three-dimensional(3D)reconstruction,virtual simulation of surgery and 3D printing optimize the surgical plan through preoperative assessment,improving the controllability and safety of intraoperative operations,and in difficult-to-reach areas of the posterior and superior liver,assistive robots reproduce the surgeon’s natural movements with stable cameras,reducing natural vibrations.Electromagnetic navigation in abdominal surgery solves the problem of conventional surgery still relying on direct visual observation or preoperative image assessment.We summarize and compare these recent trends in digital medical solutions for the future development and refinement of digital medicine in hepatobiliary surgery. 展开更多
关键词 Hepatobiliary surgery three-dimensional visualization three-dimensional printing Electromagnetic tracking Real-time navigation Robot-assisted surgery
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Three-dimensional dynamics of supported pipes conveying fluid 被引量:9
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作者 L.Wang T.L.Jiang H.L.Dai 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第6期1065-1074,共10页
This paper deals with the three-dimensional dynamics and postbuckling behavior of flexible supported pipes conveying fluid, considering flow velocities lower and higher than the critical value at which the buckling in... This paper deals with the three-dimensional dynamics and postbuckling behavior of flexible supported pipes conveying fluid, considering flow velocities lower and higher than the critical value at which the buckling instability occurs. In the case of low flow velocity, the pipe is stable with a straight equilibrium position and the dynamics of the system can be examined using linear theory. When the flow velocity is beyond the critical value, any motions of the pipe could be around the postbuckling configuration(non-zero equilibrium position) rather than the straight equilibrium position, so nonlinear theory is required. The nonlinear equations of perturbed motions around the postbuckling configuration are derived and solved with the aid of Galerkin discretization. It is found, for a given flow velocity,that the first-mode frequency for in-plane motions is quite different from that for out-of-plane motions. However, the second-or third-mode frequencies for in-plane motions are approximately equal to their counterparts for out-of-plane motions, keeping almost constant values with increasing flow velocity. Moreover, the orientation angle of the postbuckling configuration plane for a buckled pipe can be significantly affected by initial conditions, displaying new features which have not been observed in the same pipe system factitiously supposed to deform in a single plane. 展开更多
关键词 Pipe conveying fluid three-dimensional dynamics INSTABILITY Natural frequency Postbuckling configuration
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Three-dimensional Computational Fluid Dynamics Modeling of Two-phase Flow in a Structured Packing Column 被引量:4
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作者 张小斌 姚蕾 +1 位作者 邱利民 张学军 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第9期959-966,共8页
Characterizing the complex two-phase hydrodynamics in structured packed columns requires a power- ful modeling tool. The traditional two-dimensional model exhibits limitations when one attempts to model the de- tailed... Characterizing the complex two-phase hydrodynamics in structured packed columns requires a power- ful modeling tool. The traditional two-dimensional model exhibits limitations when one attempts to model the de- tailed two-phase flow inside the columns. The present paper presents a three-dimensional computational fluid dy- namics (CFD) model to simulate the two-phase flow in a representative unit of the column. The unit consists of an CFD calculations on column packed with Flexipak 1Y were implemented within the volume of fluid (VOF) mathe- matical framework. The CFD model was validated by comparing the calculated thickness of liquid film with the available experimental data. Special attention was given to quantitative analysis of the effects of gravity on the hy- drodynamics. Fluctuations in the liquid mass flow rate and the calculated pressure drop loss were found to be quali- tatively in agreement with the experimental observations. 展开更多
关键词 structured packing column two-phase flow computational fluid dynamics three-dimension
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Three-dimensional visualization technology for guiding one-step percutaneous transhepatic cholangioscopic lithotripsy for the treatment of complex hepatolithiasis 被引量:3
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作者 Yong-Qing Ye Ya-Wen Cao +6 位作者 Rong-Qi Li En-Ze Li Lei Yan Zhao-Wei Ding Jin-Ming Fan Ping Wang Yi-Xiang Wu 《World Journal of Gastroenterology》 SCIE CAS 2024年第28期3393-3402,共10页
BACKGROUND Biliary stone disease is a highly prevalent condition and a leading cause of hospitalization worldwide.Hepatolithiasis with associated strictures has high residual and recurrence rates after traditional mul... BACKGROUND Biliary stone disease is a highly prevalent condition and a leading cause of hospitalization worldwide.Hepatolithiasis with associated strictures has high residual and recurrence rates after traditional multisession percutaneous transhepatic cholangioscopic lithotripsy(PTCSL).AIM To study one-step PTCSL using the percutaneous transhepatic one-step biliary fistulation(PTOBF)technique guided by three-dimensional(3D)visualization.METHODS This was a retrospective,single-center study analyzing,140 patients who,between October 2016 and October 2023,underwent one-step PTCSL for hepatolithiasis.The patients were divided into two groups:The 3D-PTOBF group and the PTOBF group.Stone clearance on choledochoscopy,complications,and long-term clearance and recurrence rates were assessed.RESULTS Age,total bilirubin,direct bilirubin,Child-Pugh class,and stone location were similar between the 2 groups,but there was a significant difference in bile duct strictures,with biliary strictures more common in the 3D-PTOBF group(P=0.001).The median follow-up time was 55.0(55.0,512.0)days.The immediate stone clearance ratio(88.6%vs 27.1%,P=0.000)and stricture resolution ratio(97.1%vs 78.6%,P=0.001)in the 3D-PTOBF group were significantly greater than those in the PTOBF group.Postoperative complication(8.6%vs 41.4%,P=0.000)and stone recurrence rates(7.1%vs 38.6%,P=0.000)were significantly lower in the 3D-PTOBF group.CONCLUSION Three-dimensional visualization helps make one-step PTCSL a safe,effective,and promising treatment for patients with complicated primary hepatolithiasis.The perioperative and long-term outcomes are satisfactory for patients with complicated primary hepatolithiasis.This minimally invasive method has the potential to be used as a substitute for hepatobiliary surgery. 展开更多
关键词 HEPATOLITHIASIS One-step percutaneous transhepatic cholangioscopic lithotripsy Biliary disease three-dimensional visualization Clinical efficacy
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Three-dimensional visualization interactive system for digital twin workshop 被引量:8
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作者 Zhang Qinglei Yang Zhiwei +2 位作者 Duan Jianguo Liu Zhen Qin Jiyun 《Journal of Southeast University(English Edition)》 EI CAS 2021年第2期137-152,共16页
To improve the human-physical-virtual coordination and integration of the digital twin workshop,3D visual monitoring and human-computer interaction of the digital twin workshop was studied.First,a novel 6D model of th... To improve the human-physical-virtual coordination and integration of the digital twin workshop,3D visual monitoring and human-computer interaction of the digital twin workshop was studied.First,a novel 6D model of the 3D visualization interactive system for digital twin workshops is proposed.As the traditional 5D digital twin model ignores the importance of human-computer interaction,a new dimension of the user terminal was added.A hierarchical real-time data-driven mapping model for the workshop production process is then proposed.Moreover,a real-time data acquisition method for the industrial Internet of things is proposed based on OPC UA(object linking and embedding for process control unified architecture).Based on the 6D model of the system,the process of creating a 3D visualization virtual environment based on virtual reality is introduced,in addition to a data-driven process based on the data management cloud platform.Finally,the 6D model of the system was confirmed using the blade rotor test workshop as the object,and a 3D visualization interactive system is developed.The results show that the system is more transparent,real-time,data-driven and more efficient,as well as promotes the coordination and integration of human-physical-virtual,which has practical significance for developing digital twin workshops. 展开更多
关键词 digital twin workshop three-dimensional visualization human-computer interaction data driven OPC UA(object linking and embedding for process control unified architecture)
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DESIGN AND APPLICATION OF DYNAMIC MONITORING AND VISUALIZATION MANAGEMENT INFORMATION SYSTEM OF KARST LAND ROCKY DESERTIFICATION 被引量:3
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作者 HUBao-qing LIAOChi-mei YANZhi-qiang LILing QINKai-xian 《Chinese Geographical Science》 SCIE CSCD 2004年第2期122-128,共7页
In order to study the spatial-temporal change and environmental management of regional karst LUCC (land use and land cover change) and its causative environmental effect-rocky desertification by integrating qualitativ... In order to study the spatial-temporal change and environmental management of regional karst LUCC (land use and land cover change) and its causative environmental effect-rocky desertification by integrating qualitative analysis and quantitative analysis, and relying on RS, GIS and GPS (3S) techniques, karst land rocky derification dynamic monitoring and visualization management information system (KLRD.DMVM.IS) is framed, which includes design aim and structure model, function design, database design and model system design. The model system design gives priority to dynamic monitoring, drive force diagnosis, comprehensive evaluation and decision support of karst rocky desertification. From the viewpoint of model type, mathematic expression and its meaning, the dynamic monitoring models are concretely devised to reflect the spatial and temporal changing features and the trend of karst LUCC and rocky desertification. Taking Du'an Yao Autonomic County of Guangxi as an example, the KLRD.DMVM.IS is systematically analyzed in the application of the process and trend of karst LUCC and rocky desertification in Du'an County, and it provides the technical support for the study on karst land rocky desertification. 展开更多
关键词 karst rocky desertification GIS secondary development dynamic monitoring visualization management
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Science Letters:Dynamic concision for three-dimensional reconstruction of human organ built with virtual reality modelling language (VRML) 被引量:3
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作者 禹正杨 郑树森 +2 位作者 陈雷霆 何晓乾 王建军 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第7期611-616,共6页
This research studies the process of 3D reconstruction and dynamic concision based on 2D medical digital images using virtual reality modelling language (VRML) and JavaScript language, with a focus on how to realize t... This research studies the process of 3D reconstruction and dynamic concision based on 2D medical digital images using virtual reality modelling language (VRML) and JavaScript language, with a focus on how to realize the dynamic concision of 3D medical model with script node and sensor node in VRML. The 3D reconstruction and concision of body internal organs can be built with such high quality that they are better than those obtained from the traditional methods. With the function of dynamic concision, the VRML browser can offer better windows for man-computer interaction in real-time environment than ever before. 3D reconstruction and dynamic concision with VRML can be used to meet the requirement for the medical observation of 3D reconstruction and have a promising prospect in the fields of medical imaging. 展开更多
关键词 Virtual Reality Modelling Language (VRML) Direct texture mapping three-dimensional reconstruction dynamic concision
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Three-dimensional visualization of soil pore structure using computed tomography 被引量:1
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作者 Qiaoling Han Xibo Zhou +2 位作者 Lei Liu Yandong Zhao Yue Zhao 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第3期1053-1061,共9页
The geometric and spatial characteristics of pore structures determine the permeability and water retention of soils, which have important effects on soil functional diversity and ecological restoration. Until recentl... The geometric and spatial characteristics of pore structures determine the permeability and water retention of soils, which have important effects on soil functional diversity and ecological restoration. Until recently, there have not been tools and methods to visually and quantitatively describe the characteristics of soil pores. To solve this problem, this research reconstructs the geometry and spatial distribution of soil pores by the marching cubes method, texture mapping method and the ray casting method widely used in literature. The objectives were to explore an optimal method for three-dimensional visualization of soil pore structure by comparing the robustness of the three methods on soil CT images with single pore structure and porosity ranging from low (2–5%) to high (12–18%), and to evaluate the reconstruction performance of the three methods with different geometric features. The results demonstrate that there are aliases (jagged edges) and deficiency at the boundaries of the model reconstructed by the marching cubes method and pore volumes are smaller than the ground truth, whereas the results of the texture mapping method lack the details of pore structures. For all the soil images, the ray casting method is preferable since it better preserves the pore characteristics of the ground truth. Furthermore, the ray casting method produced the best soil pore model with higher rendering speed and lower memory consumption. Therefore, the ray casting method provides a more advanced method for visualization of pore structures and provides an optional technique for the study of the transport of moisture and the exchange of air in soil. 展开更多
关键词 Soil PORE STRUCTURE X-ray COMPUTED TOMOGRAPHY three-dimensional reconstruction PORE visualization
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Three-dimensional coordinates test method with uncertain projectile proximity explosion position based on dynamic seven photoelectric detection screen 被引量:2
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作者 Han-shan Li Xiao-qian Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第9期1643-1652,共10页
To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test ... To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test method, which is made up of six plane detection screens and a flash photoelectric dynamic detection screen. The three-dimensional coordinates calculation model of the projectile proximity explosion position based on seven plane detection screens with dynamic characteristics is established.According to the relation of the dynamic seven photoelectric detection screen planes and the time values,the analytical function of the projectile proximity explosion position parameters under non-linear motion is derived. The projectile signal filtering method based on discrete wavelet transform is explored in this work. Additionally, the projectile signal recognition algorithm using an improved particle swarm is proposed. Based on the characteristics of the time duration and the signal peak error for the projectile passing through the detection screen, the signals attribution of the same projectile passing through six detection screens are analyzed for obtaining precise time values of the same projectile passing through the detection screens. On the basis of the projectile fuze proximity explosion test, the linear motion model and the proposed non-linear motion model are used to calculate and compare the same group of projectiles proximity explosion position parameters. The comparison of test results verifies that the proposed test method and calculation model in this work accurately obtain the actual projectile proximity explosion position parameters. 展开更多
关键词 dynamic multi-screen array plane Flash photoelectric detection target Projectile signal processing Particle swarm Proximity explosion fuze three-dimensional coordinate
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Dynamic Visualization Approach of the Multiphase Flow Using Electrical Capacitance Tomography 被引量:1
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作者 王泽璞 陈琪 +2 位作者 王雪瑶 李志宏 韩振兴 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第2期380-388,共9页
Identifying the flow patterns is vital for understanding the complicated physical mechanisms in multiphase flows.For this purpose,electrical capacitance tomography(ECT) technique is considered as a promising visualiza... Identifying the flow patterns is vital for understanding the complicated physical mechanisms in multiphase flows.For this purpose,electrical capacitance tomography(ECT) technique is considered as a promising visualization method for the flow pattern identification,in which image reconstruction algorithms play an important role.In this paper,a generalized dynamic reconstruction model,which integrates ECT measurement information and physical evolution information of the objects of interest,was presented.A generalized objective functional that simultaneously considers the spatial constraints,temporal constraints and dynamic evolution information of the objects of interest was proposed.Numerical simulations and experiments were implemented to evaluate the feasibility and efficiency of the proposed algorithm.For the cases considered in this paper,the proposed algorithm can well reconstruct the flow patterns,and the quality of the reconstructed images is improved,which indicates that the proposed algorithm is competent to reconstruct the flow patterns in the visualization of multiphase flows. 展开更多
关键词 electrical capacitance tomography visualization flow pattern identification dynamic reconstruction algorithm
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Dynamic graph exploration by interactively linked node-link diagrams and matrix visualizations 被引量:1
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作者 Michael Burch Kiet Bennema ten Brinke +3 位作者 Adrien Castella Ghassen Karray Sebastiaan Peters Vasil Shteriyanov Rinse Vlasvinkel 《Visual Computing for Industry,Biomedicine,and Art》 EI 2021年第1期219-232,共14页
The visualization of dynamic graphs is a challenging task owing to the various properties of the underlying relational data and the additional time-varying property.For sparse and small graphs,the most efficient appro... The visualization of dynamic graphs is a challenging task owing to the various properties of the underlying relational data and the additional time-varying property.For sparse and small graphs,the most efficient approach to such visualization is node-link diagrams,whereas for dense graphs with attached data,adjacency matrices might be the better choice.Because graphs can contain both properties,being globally sparse and locally dense,a combination of several visual metaphors as well as static and dynamic visualizations is beneficial.In this paper,a visually and algorithmically scalable approach that provides views and perspectives on graphs as interactively linked node-link and adjacency matrix visualizations is described.As the novelty of this technique,insights such as clusters or anomalies from one or several combined views can be used to influence the layout or reordering of the other views.Moreover,the importance of nodes and node groups can be detected,computed,and visualized by considering several layout and reordering properties in combination as well as different edge properties for the same set of nodes.As an additional feature set,an automatic identification of groups,clusters,and outliers is provided over time,and based on the visual outcome of the node-link and matrix visualizations,the repertoire of the supported layout and matrix reordering techniques is extended,and more interaction techniques are provided when considering the dynamics of the graph data.Finally,a small user experiment was conducted to investigate the usability of the proposed approach.The usefulness of the proposed tool is illustrated by applying it to a graph dataset,such as e co-authorships,co-citations,and a Comprehensible Perl Archive Network distribution. 展开更多
关键词 dynamic graph visualization Node-link diagrams Adjacency matrices LAYOUTS Reorderings
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Evaluating the use of three-dimensional reconstruction visualization technology for precise laparoscopic resection in gastroesophageal junction cancer 被引量:1
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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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