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Geological environment is the decisive factor affecting the development of underground space especially in historic urban areas with many constraints. It is important to evaluate the suitability of geological environment for the development of underground space. Considering the geological and historical environment of Guanqian district in Suzhou, 13 evaluation indexes were selected and each combined weight was calculated based on the combination of analytic hierarchy process and entropy weight method. The evaluation results calculated by fuzzy comprehensive evaluation method were displayed in 3D visualization by ArcGIS. The results show that about 18. 7% of the shallow underground space is suitable for development, 59. 1% of the shallow underground space is sub-suitable, 21. 2% of the shallow underground space is generally suitable, and only 1. 0% of the shallow underground space is poor suitability. About 11. 6% of the sub-shallow underground space is suitable for development, 76. 7% of the sub-shallow underground space is sub- suitable, 11. 7% of the sub-shallow underground space is generally suitable, and there is no space with poor suitability for sub-shallow underground space. [ABSTRACT FROM AUTHOR]

BACKGROUND: Currently, there have been studies on three-dimensional digitalization and visualization systems for adult acupoints, but there are not many reports on the visualization of pediatric acupoints based on real pediatric digital sectional anatomical datasets. OBJECTIVE: To design and develop a digital three-dimensional visualization system for children’s neck acupoints, to provide a basis for acupuncture and moxibustion, meridian and acupoint science teaching, clinical practice, acupuncture manipulation practice, and acupuncture safety research, and to provide a basis for the development of children’s acupoint simulation system. METHODS: Based on a real cross-sectional anatomical dataset of pre-school boys, a three-dimensional digital virtual anatomical model of the neck region of children and internal multi-organ three-dimensional reconstruction were completed using PhotoShop 2021 and Digihuman Reconstruction System software. A database of 11 acupoints was compiled, including Fengfu and Fengchi, using the Unity database language. A three-dimensional model of children’s neck anatomy, acupoint database, and writing acupuncture operation codes were integrated in Unity3D software. A three-dimensional digital visualization system for children’s neck acupoints was successfully created, which integrated simulation acupoint positioning, three-dimensional acupoint anatomy, acupuncture training, clinical teaching, and acupuncture safety research. RESULTS AND CONCLUSION: (1) This study was based on real child specimens. Manual layer by layer segmentation of cross-sectional images was used to ensure the accuracy of the three-dimensional model to the greatest extent possible. The 3D software Digihuman Reconstruction System was utilized to extract and save independent segmentation data. PhotoShop 2021 software was collaborated with to complete dozens of three-dimensional reconstruction anatomical models of the outer skin of the neck and its internal bone structure, cervical spinal cord, blood vessels and nerves, muscles, and ligaments in children. The basic morphology and overall contour integrity verification of each independent structure were completed in MeshLab software. The 3-material research 13.0 software was applied for final fine tuning and anatomical position confirmation, successfully simulating and restoring the true anatomical morphology of the neck of preschool children. (2) Based on and referring to the national standards of the People’s Republic of China, a database of commonly used acupoints in children’s neck region was collected and organized, including their names, meridians, positioning, local anatomy, needle insertion levels, acupuncture methods, acupuncture accidents and prevention, acupoint indications, and two-dimensional anatomical sectional images. (3) Unity3D software was employed to integrate the three-dimensional model of children’s neck, acupuncture simulation operation, and acupoint database, and a three-dimensional digital children’s neck acupoint acupuncture visualization system was successfully constructed. The system displayed information on children’s neck acupoints, two-dimensional and three-dimensional anatomical structures, and achieved two-dimensional and three-dimensional acupuncture simulation functions and acupuncture safety research functions for children’s neck acupoints. Based on the ultra-thin sectional anatomical dataset of real child specimens, the first three-dimensional digital and visualization system for acupoints in the neck region of children had been constructed. Compared with previous acupoint acupuncture systems, it is more in line with the anatomical and morphological development characteristics of Asian children and has high application value in the fields of acupuncture safety research, clinical teaching, and acupuncture simulation training. [ABSTRACT FROM AUTHOR]

This study aims to integrate and visually present the drilling, geophysical, and pollution monitoring data of contaminated sites in three-dimensional space. By employing web front-end rendering technology based on VTK, this research designs a specialized three-dimensional visualization software and develops it to enable detailed analysis of the underground space on site. The study processes and models raw data from a specific contaminated site, develops corresponding data interfaces, and utilizes VTK technology for front-end three-dimensional visualization rendering. Not only does the research enhance the visual presentation of data, but it also achieves advanced functions such as online sectioning, thereby enriching the technical methods for web-based three-dimensional visualization overlay analysis of contaminated sites. [ABSTRACT FROM AUTHOR]

Objectives: Accurately describing and understanding the bridge construction process is of great significance to students' learning and field personnel's fine management. However, the bridge construction process involves a large number of objects, complex behaviors, and variable states, which leads to problems such as poor standardization and low cognitive efficiency in expression. Methods: This paper proposes a knowledge-guided three-dimensional visualization method of spatiotemporal narrative of bridge construction process. First, we construct a bridge construction knowledge map with "object-behavior-state" three-domain association by analyzing the bridge construction process, then break through the key technologies of narrative element analysis and matching, 3D scene mapping and instantiation, and 3D dynamic visualization of spatiotemporal narrative. Finally, we develop a prototype system and carries out case study experimental analysis. Results: The results show that the correct rate of answering questions in the experimental group reaches 76.5%, which is 13.2% higher than that of the control group; under the comprehensive perspective of clarity, richness and comprehension difficulty, 78.8% of the personnel in the experimental group have good cognitive experience, which is 45.5% higher than that of the control group. Conclusions: By accurately describing the bridge construction objects, features and interrelationships, the unified expression and association management of bridge construction knowledge map is realized, and based on this, the three-dimensional dynamic visualization expression of the bridge construction process is carried out by using spatiotemporal narratives, which effectively enhances the education level of bridge construction process cognition with the help of interactivity and immersion of three-dimensional scenes. [ABSTRACT FROM AUTHOR]

With the continuous development of dredging engineering and dredging business, the requirements for monitoring the dredging construction process are also increasing. Aiming at the problems of poor display effect and low accuracy in 3D visualization monitoring during the dredging process of existing dredgers, a universal 3D visualization system for dredger construction operations was designed and developed based on the Unity3D engine. The system realizes the 3D visualization display of key dredging equipment driving, underwater terrain generation and rendering, and real-time terrain reconstruction. Through actual dredger application verification, the system can effectively improve construction efficiency and quality, enhance construction accuracy, reduce the occurrence of missed excavation and over excavation, and has important engineering application value. [ABSTRACT FROM AUTHOR]

In order to achieve visual management of geological hazard in Huangshui River Basin of Qinghai Province and improve the efficiency of disaster information processing, the design and development of a disaster 3D visualization system and a backend information management system were carried out through oblique photogrammetry and field investigation, combined with database, front-end and back-end technologies. The 3D visualization system was based on the Cesium engine, which has the functions of multidimensional display of the earth, fast positioning, and base map addition. It has expanded and developed three characteristic modules: data loading, spatial processing, and roaming display. It can load vector data, image data, and oblique photography models of the research area, meeting the needs of spatial measurement. It has achieved the dual control analysis of “ hidden danger points + risk areas” by drawing labels on the model and combining on-site investigation results. The backend information management system has achieved spatial query and analysis of basic disaster situations, development trends, precipitation, population, GDP and other information within the region, providing technical support for geological disaster risk assessment and protection. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Urban Geology is the property of Urban Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Journal of Oral & Maxillofacial Surgery is the property of Shanghai Jiao Tong University, College of Stomatology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To evaluate the clinical application of the terminal branches portal vein embolization and multimode imaging technology in precise hepatectomy for patients with huge hepatocellular carcinoma. Methods Clinical data of 52 patients of huge hepatocellular carcinoma underwent precise hepatectomy with the help of multimode imaging technology in Yuebei People′s Hospital between Feb. 2018 and Nov. 2021 were retrospectively analyzed. According to the treatment method, the patients were divided into direct surgical resection group (control group, 27 cases). And terminal branches portal vein embolization followed by surgical resection group (study group, 25 cases). The multimode imaging technology fusing three-dimensional reconstruction which converted from CT imaging, three-dimensional visualization, three dimensional printing and augmented reality in assessing the hepatic anatomy, instructing preoperative planning and navigating operation. The terminal branches portal vein embolization technology blocked the interconnected portal vein of the two sides of the liver, and promoted the future liver remnant before surgery. Perioperative results and postoperative efficacy of the two groups such as the surgical methods, operative time, intraoperative blood loss, and postoperative complications were observed and analyzed. Results The multimode imaging technology were successfully applied in all 52 patients, achieved satisfying preoperative assessment, surgical planning, and intraoperative navigation. The future liver remnant of patients in the study group were promoted effectively, (93 ~ 322 mL, media183 mL). All patients underwent surgery successfully, there were none perioperative death, no serious postoperative complications such as bleeding, biliary leakage and liver failure occurred. The hepatic blood flow occlusion time, intraoperative blood loss, postoperative length of stay and the incidence of postoperative complications of the study group were (27.6 ± 11.6) min, 236 (100) mL, (10.8 ± 2.4) d, 12.0% (3/25), respectively. Significantly less than which in the control group (34.4 ± 10.9 min, 292 (150) mL, (13.1 ± 4.1) d, 37.0% (10/27) (P < 0.05). The operative time were (209.6 ± 36.5) min and (237.0 ± 69.1) min in the control group respectively, there was no significant difference (P > 0.05). There were 5 and 11 cases of recurrence respectively in two groups, but no statistical difference between two groups (χ² = 0.735, P > 0.05). Conclusion The terminal branches portal vein embolization and multimode imaging technology can improve the safety and effect of precise hepatectomy for patients with huge hepatocellular carcinoma through augmented the future liver remnant, accurate preoperative planning and surgical navigation. [ABSTRACT FROM AUTHOR]

Objective: To explore the clinical value of MRI three-dimensional visualization (3DV) reconstruction technology in the evaluation of complex anal fistula. Methods: The preoperative MRI data of 46 patients with complicated anal fistula confirmed by operation were collected retrospectively and divided into 2D-MRI group and 3DV-MRI group according to the image. The number of internal orifice, fistula and pus cavity were observed respectively, and the images of the two groups were scored according to the scoring standard of Likert scale from the four aspects of clinical concern. Results: In the two groups, 64 (81.0%) and 70 (88.6%) internal orifices, 82 (85.4%) and 84 (87.5%) fistulas, 33 (91.7%) and 32 (88.9%) pus cavities were detected respectively. Conclusion　Both 2D MRI and 3DV MRI reconstruction images have a high detection rate and accuracy in the preoperative diagnosis of complex anal fistula; Compared with conventional 2D-MRI, 3DV-MRI images can provide more valuable guidance information for clinicians in the diagnosis and treatment of complex anal fistula, increase clinicians' understanding of the extent, scope and adjacent structures of the disease, and have better clinical application value in reducing postoperative recurrence and damage to the anal sphincter. [ABSTRACT FROM AUTHOR]

At present, browsers are becoming more and more mature in 3D graphics display technology. Using WebGL's third-party library Three. js to display fish 3D models is not only simple and convenient but also has obvious cross-platform advantages. Through the study of Three. js, the problems of building a fish 3D display system in the past technology, such as fewer functions,complicated construction, the need to install plug-ins to browse, and cannot to be used across platforms, can promote the related applications of fish visualization. This research mainly uses 3ds MAX software to build the fish model and herbarium model, realizes loading and interaction of models through the Three. js library, and combines Three. js with Bootstrap framework, PHP technology, MySQL and other technologies to build the fish model display system. After completing the system construction, deploy the system to the Tencent Cloud server to complete the performance test. The results show that: this system realizes fish model search and viewing, paging display, second loading in an online environment, step-by-step loading of fish herbarium scene models, viewing fish models in Mobile VR mode, and users uploading models and displaying models online, sharing models and other functions, with good application value. This research can provide references for fish modeling, fish 3D model compression, fishery large model scene loading, and fishery visualization. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Railway bridge construction is long and complex in its process with low visualization, involving a variety of professionals, resulting in low efficiency and low refinement. In view of this development status, BIM technology is used to refine the railway swivel bridge construction to solve the problems of scheme feasibility, structural collision, schedule control and collaborative management in traditional construction modes. Based on the swivel bridge on the Beijing -Harbin Railway Line and the BIM technology, refined management of the construction is realized, the visual interactive analysis of bridge and site information is completed, and a collaborative management platform is independently developed for the project management, which accelerates the speed of the construction works and improves the efficiency. It has practical significance for promoting intelligent construction of bridge works. [ABSTRACT FROM AUTHOR]

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of East China Geology / Huadong dizhi is the property of Editorial Department of East China Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the risk of over-impoundment under the condition of flood control of the reservoir, taking Gaobei hydrojunction project of Hanjiang River as the research object, an over-impoundment model of reservoir area based on 2D shallow water equations and Villemonte formula was established. The model is reasonable and reliable. Considering the uncertainty of actual water inflow and dispatching scheme, the dynamic factors such as inflow and dispatching scheme were introduced into the model to realize the dynamic analysis model of over-impoundment inundation risk of Gaobei hydro-junction, and the simulation of over-impoundment and three-dimensional(3D) visual display under any inflow and dispatch schemes based on 3D real scene modeling technology were realized. The research results can provide decision-making support for the early warning and forecasting of the risk of over-impoundment inundation, reservoir operation, flood avoidance and transfer, and the formulation and improvement of flood control measures in Gaobei reservoir area. It can also provide reference for other reservoirs. [ABSTRACT FROM AUTHOR]

Copyright of Uranium Geology is the property of Uranium Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to visually display the three dimensional spatial distribution of pollutants and define the volume polluted contaminated soil, a three-dimensional visual model can be built to achieve this goal. Based on EVS software, this paper adopts three-dimensional stratum modeling method and takes a slag dump Yuxi city as the research object to carry out three-dimensional spatial interpolation analysis of pollutants. The mercury pollution range and volume in Kriging, IDWS, IDWM and NN interpolation models were compared, and the model accuracy was evaluated by cross-validation method. The results show that the mean error (ME ) and mean absolute error ( MAE) of the four interpolation models are NN > IDWS > IDWN > Kriging, root mean square error (RMSE) is NN> IDWS> Kriging > IDWM and Kriging interpolation models have the highest interpolation accuracy. Mercury pollution was concentrated in the slag layer, and the Kriging interpolation model calculated that the contaminated volume of soil was 36787.968 m³ • The results of this study have broad application prospects in soil remediation in the future. [ABSTRACT FROM AUTHOR]

Copyright of Railway Investigation & Surveying is the property of Railway Investigation & Surveying Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geology & Resources is the property of Geology & Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nonferrous Metals (Mining Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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BACKGROUND: For complex intertrochanteric fractures, there is lack of effective preoperative planning, which lead to prolonged operation time and increased difficulty. At the same time, the application of digital orthopedics three-dimensional (3D) visualization technology in the operation of intertrochanteric fracture lacks clinical application verification. OBJECTIVE: 3D visualization technology for digital orthopedics can be used to clarify the displacement of complex intertrochanteric fractures and realize preoperative simulated reduction and fixation, thus providing ideas and methods for intraoperative reduction and fixation of complex intertrochanteric fractures. METHODS: Patients with complex intertrochanteric fractures (AO typing: A2 and A3) admitted to Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from January 2019 to January 2020 were selected and randomly divided into Mimics 3D reconstruction simulation reduction group and control group according to the order of admission. According to medical procedures, all the patients were implemented with plain X-ray examination of the affected hip and CT scanning of the affected hip. Patients in the Mimics 3D reconstruction simulation reduction group achieved 3D reconstruction through Mimics 17.0 software, and then the shattered fracture blocks were simulated reduction and fixation. Patients in the control group were treated with internal fixation only according to preoperative imaging examination. Data were collected to compare the differences between the two groups in terms of operation time, intraoperative blood loss, hip reduction quality score, and hip function during follow-up. RESULTS AND CONCLUSION: (1) The operation time was significantly shorter in the Mimics 3D reconstruction simulation reduction group than that in the control group, and intraoperative blood loss was significantly reduced in the Mimics 3D reconstruction simulation reduction group compared with the control group, and the difference between the two groups was statistically significant (P < 0.05). (2) The excellent and good rate of hip reduction quality score was significantly higher in the Mimics 3D reconstruction simulation reduction group (96%) than that in the control group (82%) (P < 0.05). (3) The hip function score was significantly higher in the Mimics 3D reconstruction simulation reduction group (95.7±5.8) points than that in the control group (82.9±10.2) points 6 months after surgery (P < 0.05). (4) The results confirmed that for complex femoral intertrochanteric fractures, preoperative 3D reconstruction simulations by Mimics software reset can help to get a comprehensive understanding of fracture displacement, detailed guide the choice of intraoperative fracture reduction and internal fixation, help to shorten the operation time, lessen intraoperative blood loss, and improve the curative effect of intertrochanteric fracture. [ABSTRACT FROM AUTHOR]

Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

为提高结构施工监测管理的信息化程度,实现结构施工监测及预警信息的三维可视化和信息共享,提出在BIM平台上开发适用于超高层及大跨空间结构施工过程的结构健康监测管理系统。在明确系统需求,定义相应的功能模块,描述系统工作流程,建立系统整体框架的基础上,基于Revit API二次开发搭建了系统平台,并将该平台应用于实际项目的结构施工监测管理中。研究表明,该平台可实现监测数据的快速获取及三维可视化查看,通过建立BIM与现场监测数据的融合机制,提高了施工过程中监测信息流通,能够进行施工现场集成通讯与动态监管、施工时变结构监测及预警,最终打破常规监测信息管理方法,实现建设全过程的监测信息分享。

Copyright of Journal of Beijing University of Technology is the property of Journal of Beijing University of Technology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shenzhen University Science & Engineering is the property of Editorial Department of Journal of Shenzhen University Science & Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the continuous improvement of user needs and the continuous enrichment of spatial data, the same geospatial scope includes different types of spatial data such as terrain, remote sensing images, and 3D models of oblique photogrammetry. 3D WebGIS cannot effectively load different types of spatial da⁃ ta in the same scene . This paper proposes a spatial data loading optimization method for 3D WebGIS to op⁃ timize the efficient loading of multiple types of spatial data. First, using the structural features of 3D Tiles with regular enclosing volume shapes and overlapping regions, a fast growth algorithm based on binary tree is proposed to locate and extract the outer boundary of 3D model. Then, there were jagged protrusions on the outer boundary of the roughly extracted polygon. In order to solve the problem, a polygon simplification method based on two neighboring points was proposed to optimize the outer boundary of the polygon to achieve accurate extraction of the outer boundary of the 3D model. Finally, by judging the inclusion of map tile and terrain tile data relationship to achieve selective loading of tile data. Experiments show that when the viewpoint height is below 300 meters, the total load of map tile data can be reduced by about 40%, indi⁃ cating that the optimization method in this paper can significantly improve the data loading efficiency of the system without affecting the visualization of 3D WebGIS . [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Interventional treatment can also be used as a palliative treatment for patients who cannot be surgically removed. However, the positioning of the lesion at the beginning of the operation or the catheter during the interventional treatment can only be accurately and clearly displayed through the two-dimensional image, and is related to the operator’s own experience and understanding of the image. The 3D printing model is a physical model with high simulation and individualized features, and has the advantages of individualization and precision in the medical field. It is currently widely used in orthopedics, oral and maxillofacial surgery, but the application in the treatment of craniocerebral aneurysms is rarely reported. OBJECTIVE: To summarize the classification and treatment status of cerebral aneurysms, and to prospect the application prospect of 3D printing technology in the treatment of cerebral aneurysms. METHODS: The authors retrieved CNKI, WanFang, PubMed, and EI database. The search terms were “cerebral aneurysm, clinical classification, treatment, 3D printing”. A total of 96 relevant literatures were retrieved, and 51 articles were summarized according to the inclusion and exclusion criteria. Specifically, it included the classification of cerebral aneurysms, craniotomy and interventional therapy, and the application status of 3D printing technology. RESULTS AND CONCLUSION: At present, the treatment methods of cerebral aneurysms commonly used in clinical practice have their own advantages and limitations. In this case, 3D visualization and 3D printing technology are proposed, which is an important supplement for the clinical treatment of patients with cerebral aneurysms. It can display organ anatomy and spatial structure more intuitively and accurately through operations such as enlargement, rotation and transparency. At the same time, it can accurately locate the aneurysm site, calculate the aneurysm size and volume, and define the aneurysm morphology. This is significant in preoperative diagnosis, planning of surgery, precise operation during surgery, and improvement of surgical success rate for the brain aneurysm. Simultaneously, the solid model of 3D printing is also widely used in the aspects of disease communication and training of resident surgical operations. By summarizing the research progress of 3D printing technology in the treatment of cerebral aneurysms, we have a clearer understanding of the application of 3D visualization and 3D printing technology. Whether it is combined with fluid mechanics for hemodynamic research or refined treatment based on existing treatment schemes, it has promoted the development of clinical research. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Computer Engineering & Applications is the property of Beijing Journal of Computer Engineering & Applications Journal Co Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In view of the frequent occurrence of flood disasters in changing environments and the limitation of 2D display of flood simulation results, a high-resolution numerical model is coupled with 3D visualization technology. Taking the flooding process of Fengxi, Shaanxi Province and Morpeth, England as examples, it is simulated by the numerical model based on GPU, so as to obtain more accurate information of flood time and inundation area. The study realizes the coupling of the numerical model and the Unity 3D platform, 3D visual display of flood process and preliminarily realizes the flood simulation based on 3D stereo imaging through the shutter 3D technology. The results show that the calculated results are in good agreement with the measured datas, the average relative errors of the accumulated water area are 6.235% and 1.505%, respectively, and the interactive display of water disaster process information in 3D environment is truly realized. It can be used as an effective collaborative platform to enhance the communication and collaboration between relevant personnel, and provide accurate and effective scientific basis for decision-makers, which has a good application prospect in the field of water resources. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Vascular structure is an important basis for maintaining cervical spinal cord function. To evaluate the involvement of microvessels in cervical spinal cord injury and treatment, it is necessary to carry out a good three-dimensional visualization and accurate quantitative analysis of the normal cervical spinal cord microvascular structure, but there are few reports about it. OBJECTIVE: To investigate the three-dimensional visualization and quantitative analysis of normal cervical spinal cord microvascular structure in rats by barium sulfate perfusion combined with micro-CT scanning, and to lay a foundation for the later evaluation of the involvement degree of microvessels in cervical spinal cord injury and the measurement of therapeutic effect. METHODS: Five adult male SD rats weighing 280-320 g were included. All animal operation procedures were implemented in accordance with the relevant national guidelines for the use of laboratory animals, and were approved by the Animal Use Ethics Committee of Southern Medical University. After rats were deeply anesthetized, vascularization was performed with warm heparin normal saline, polyformaldehyde and barium sulfate perfusion through cardiac puncture. Cervical spinal cord tissue was taken and placed in micro-CT for scanning and three-dimensional reconstruction. Quantitative analysis of the ratio of microvascular volume to tissue volume, ratio of vascular surface area to tissue volume, number of blood vessels, diameter of blood vessels, separation degree of blood vessels, connectivity density, structural model index and the number, percentage and volume of microvessels with different diameters were quantitatively analyzed. RESULTS AND CONCLUSION:（1） After three-dimensional reconstruction and visualization, the microvascular structure in the cervical spinal cord was clearly visible, showing the anterior and posterior arteries of the cervical spinal cord as well as several branch arteries.（2） Quantitative analysis results of microvascular index showed that ratio of microvascular volume to tissue volume was 0.022±0.002; ratio of vascular surface area to tissue volume was（52.370±6.271） mm-1; number of blood vessels was（0.604±0.076） mm-1; diameter of blood vessels was（0.040±0.005） μm; separation degree of blood vessels was（1.762±0.255） μm; connectivity density was（2.661±0.757） mm-3; structural model index was（4.400±0.129）. The number, percentage and volume of microvessels in cervical spinal cord with different diameters were quantified successfully.（3） Barium sulfate perfusion combined with micro-CT scanning can achieve three-dimensional visualization and accurate quantitative analysis of normal cervical spinal cord microvascular structure in rats, laying a good foundation for the later evaluation of the involvement of microvessels during cervical spinal cord injury and the measurement of therapeutic eff ect. [ABSTRACT FROM AUTHOR]

In order to solve the formation control problem for unmanned aerial vehicle（UAV）in a complex environment， a distributed formation controller is designed considering the external disturbance and incomplete feedback of state information. By using the position feedback，a state observer is proposed based on second⁃order precise differentiator. Then，the velocity of UAV and the estimate of external disturbance are derived. Combining the estimation information and the positions and velocities of its adjacent UAVs，the formation controller and attitude tracking controller are designed based on the continuous twisting sliding mode control method. The stability analysis ensures the stability of UAV's closed loop system. The control algorithm is verified on the Matlab/Simulink and a software - in - the - loop simulation platform，and the proposed method is verified and demonstrated via 3D visualization. [ABSTRACT FROM AUTHOR]

The pore structure in the compacted zone is the key factor affecting the underflow concentration of gravity in the full tailings. The quantitative analysis o£ its geometric characteristics is rare. The in-situ morphology and distribution of pores were obtained by CT tomography and 3D reconstruction technology. The variation characteristics of key parameters such as porosity, Feret diameter, and pore roundness were analyzed, and the shearing effect on the pore structure of high-concentration bed unclassified-tailings was revealed. The results show that the addition of 2 rpm shear decreases the porosity o£ the tailings bed by 13. 43%，but the average number of pores does not change significantly. The pores with/without shear are distributed in the range of 0 -- 20 ptm of Feret diameter, occupying 30. 67% and 46. 07%. The shearing effect reduces the pore roundness by 9. 86% in the range of 0. 9 -- 1，but the pore elongation and flatness do not change much； the pore number decreases by 14. 45% in the range of 0. 45_0. 5 and 0. 95 -- 1. 0. Therefore，the shearing effect can reduce the porosity of the tailings compacted bed and decrease the number of pore Feret diameters in the range of 0 -- 20 pm，but it has little effect on the average number of pores. Shearing action can reduce the number of pores in the range of 0. 9 -- 1 roundness, but there is no obvious effect on the elongation and flatness. The influence of the roughness in the range of 0. 45 -- 0. 5 and 0. 9 -- 1 is large. [ABSTRACT FROM AUTHOR]

The traditional protection of this kind of cultural heritage focuses on text, pictures, and video, leading to poor user experience and dissemination. This paper proposed a new approach of digitalization by using three dimensional (3D) laser scanning, 3D visualization and virtual reality. Taking the bronze acupuncture figure with acupoints collected by Hubei Provincial Museum as an example, this paper firstly applied 3D laser scanning technology to capture 3D point cloud data of it. Secondly, it represented and stored knowledge models of traditional Chinese medicine through XML(extensible markup language ). Thirdly, it proposed a mesh simplification algorithm based on modified quadric error metric and progressive mesh construction to automatically generate multi resolution 3D models. Finally, this paper developed a Unity engine based virtual and interactive system for bronze acupuncture figure, and provided the 3D visualization and interactive query of acupoints, meridians and common diseases. The proposed method is able to provide a reference solution for the digital protection and dissemination of historical relics and intangible cultural heritage. [ABSTRACT FROM AUTHOR]

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Special Oil & Gas Reservoirs is the property of Special Oil & Gas Reservoirs Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)