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Cellular interplay to 3D in vitro microphysiological disease model:cell patterning microbiota-gut-brain axis 被引量:1
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作者 Kamare Alam Lakshmi Nair +6 位作者 Souvik Mukherjee Kulwinder Kaur Manjari Singh Santanu Kaity Velayutham Ravichandiran Sugato Banerjee Subhadeep Roy 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第3期320-357,共38页
The microbiota-gut-brain axis(MGBA)has emerged as a key prospect in the bidirectional communication between two major organ systems:the brain and the gut.Homeostasis between the two organ systems allows the body to fu... The microbiota-gut-brain axis(MGBA)has emerged as a key prospect in the bidirectional communication between two major organ systems:the brain and the gut.Homeostasis between the two organ systems allows the body to function without disease,whereas dysbiosis has long-standing evidence of etiopathological conditions.The most common communication paths are the microbial release of metabolites,soluble neurotransmitters,and immune cells.However,each pathway is intertwined with a complex one.With the emergence of in vitro models and the popularity of three-dimensional(3D)cultures and Transwells,engineering has become easier for the scientific understanding of neurodegenerative diseases.This paper briefly retraces the possible communication pathways between the gut microbiome and the brain.It further elaborates on three major diseases:autism spectrum disorder,Parkinson’s disease,and Alzheimer’s disease,which are prevalent in children and the elderly.These diseases also decrease patients’quality of life.Hence,understanding them more deeply with respect to current advances in in vitro modeling is crucial for understanding the diseases.Remodeling of MGBA in the laboratory uses many molecular technologies and biomaterial advances.Spheroids and organoids provide a more realistic picture of the cell and tissue structure than monolayers.Combining them with the Transwell system offers the advantage of compartmentalizing the two systems(apical and basal)while allowing physical and chemical cues between them.Cutting-edge technologies,such as bioprinting and microfluidic chips,might be the future of in vitro modeling,as they provide dynamicity. 展开更多
关键词 Microbiota-gut-brain axis Neurodegeneration 3d disease model Organoid Transwell system
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3D Road Network Modeling and Road Structure Recognition in Internet of Vehicles
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作者 Dun Cao Jia Ru +3 位作者 Jian Qin Amr Tolba Jin Wang Min Zhu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1365-1384,共20页
Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transp... Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transportationsystem. The movement of vehicles and the three-dimensional (3D) nature of the road network cause the topologicalstructure of IoV to have the high space and time complexity.Network modeling and structure recognition for 3Droads can benefit the description of topological changes for IoV. This paper proposes a 3Dgeneral roadmodel basedon discrete points of roads obtained from GIS. First, the constraints imposed by 3D roads on moving vehicles areanalyzed. Then the effects of road curvature radius (Ra), longitudinal slope (Slo), and length (Len) on speed andacceleration are studied. Finally, a general 3D road network model based on road section features is established.This paper also presents intersection and road section recognition methods based on the structural features ofthe 3D road network model and the road features. Real GIS data from a specific region of Beijing is adopted tocreate the simulation scenario, and the simulation results validate the general 3D road network model and therecognitionmethod. Therefore, thiswork makes contributions to the field of intelligent transportation by providinga comprehensive approach tomodeling the 3Droad network and its topological changes in achieving efficient trafficflowand improved road safety. 展开更多
关键词 Internet of vehicles road networks 3d road model structure recognition GIS
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Review of Artificial Intelligence for Oil and Gas Exploration: Convolutional Neural Network Approaches and the U-Net 3D Model
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作者 Weiyan Liu 《Open Journal of Geology》 CAS 2024年第4期578-593,共16页
Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Ou... Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Our review traces the evolution of CNN, emphasizing the adaptation and capabilities of the U-Net 3D model in automating seismic fault delineation with unprecedented accuracy. We find: 1) The transition from basic neural networks to sophisticated CNN has enabled remarkable advancements in image recognition, which are directly applicable to analyzing seismic data. The U-Net 3D model, with its innovative architecture, exemplifies this progress by providing a method for detailed and accurate fault detection with reduced manual interpretation bias. 2) The U-Net 3D model has demonstrated its superiority over traditional fault identification methods in several key areas: it has enhanced interpretation accuracy, increased operational efficiency, and reduced the subjectivity of manual methods. 3) Despite these achievements, challenges such as the need for effective data preprocessing, acquisition of high-quality annotated datasets, and achieving model generalization across different geological conditions remain. Future research should therefore focus on developing more complex network architectures and innovative training strategies to refine fault identification performance further. Our findings confirm the transformative potential of deep learning, particularly CNN like the U-Net 3D model, in geosciences, advocating for its broader integration to revolutionize geological exploration and seismic analysis. 展开更多
关键词 Deep Learning Convolutional Neural Networks (CNN) Seismic Fault Identification U-Net 3d model Geological Exploration
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基于单片机开发板和3D打印的一种多参数呼吸训练装置的研究开发
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作者 赵东升 张龙 +2 位作者 孔康辉 郭鸣周 娄阳 《中国医疗设备》 2024年第6期17-22,29,共7页
目的通过野火骄阳32单片机开发板和3D建模及打印技术进行软硬件开发,实现一种多参数呼吸训练装置的专利样机转化。方法利用野火骄阳32单片机开发板开发应用程序,通过单片机开发板实现流量信号和压力信号的输入,舵机阀、涡轮风机、电磁... 目的通过野火骄阳32单片机开发板和3D建模及打印技术进行软硬件开发,实现一种多参数呼吸训练装置的专利样机转化。方法利用野火骄阳32单片机开发板开发应用程序,通过单片机开发板实现流量信号和压力信号的输入,舵机阀、涡轮风机、电磁阀的控制输出与上位机的数据通信等功能;样机非标零部件通过3D建模及打印技术完成制造,并将单片机开发板、标准零部件和非标零部件进行组合以完成样机开发。结果野火骄阳32单片机开发实现了传感器数据采集、运动部件的控制输出、上位机软件的数据上传和接收;3D建模及打印技术实现了非标零部件及机器外壳的制作,以低成本成功制作出样机;样机通过质控仪检测,流量值误差范围为±15%,气道压力值误差范围为±[2%FS(满量程)+4%×实际读数],样机参数精度满足JJF1234-2018《呼吸机校准规范》要求。结论野火骄阳32单片机开发板和3D建模及打印技术的应用,以低成本实现了样机制作,能够为专利的商业转化提供重要参考,为医工专利转化提供了一种新的思路。 展开更多
关键词 单片机开发板 3d建模及打印技术 专利转化 控制系统 压力传感器 流量传感器
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Building 3D CityGML models of mining industrial structures using integrated UAV and TLS point clouds
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作者 Canh Le Van Cuong Xuan Cao +2 位作者 Anh Ngoc Nguyen Chung Van Pham Long Quoc Nguyen 《International Journal of Coal Science & Technology》 EI CAS CSCD 2023年第5期158-177,共20页
Mining industrial areas with anthropogenic engineering structures are one of the most distinctive features of the real world.3D models of the real world have been increasingly popular with numerous applications,such a... Mining industrial areas with anthropogenic engineering structures are one of the most distinctive features of the real world.3D models of the real world have been increasingly popular with numerous applications,such as digital twins and smart factory management.In this study,3D models of mining engineering structures were built based on the CityGML standard.For collecting spatial data,the two most popular geospatial technologies,namely UAV-SfM and TLS were employed.The accuracy of the UAV survey was at the centimeter level,and it satisfied the absolute positional accuracy requirement of creat-ing all levels of detail(LoD)according to the CityGML standard.Therefore,the UAV-SfM point cloud dataset was used to build LoD 2 models.In addition,the comparison between the UAV-SfM and TLS sub-clouds of facades and roofs indicates that the UAV-SfM and TLS point clouds of these objects are highly consistent,therefore,point clouds with a higher level of detail and accuracy provided by the integration of UAV-SfM and TLS were used to build LoD 3 models.The resulting 3D CityGML models include 39 buildings at LoD 2,and two mine shafts with hoistrooms,headframes,and sheave wheels at LoD3. 展开更多
关键词 3d modelling CityGML-Mining industry UAV Terrestrial laser scanning Point cloud
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Building Information Modeling-Based Secondary Development System for 3D Modeling of Underground Pipelines 被引量:3
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作者 Jun Chen Rao Hu +1 位作者 Xianfeng Guo Feng Wu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第5期647-660,共14页
Underground pipeline networks constitute a major component of urban infrastructure,and thus,it is imperative to have an efficient mechanism to manage them.This study introduces a secondary development system to effici... Underground pipeline networks constitute a major component of urban infrastructure,and thus,it is imperative to have an efficient mechanism to manage them.This study introduces a secondary development system to efficiently model underground pipeline networks,using the building information modeling(BIM)-based software Revit.The system comprises separate pipe point and tubulation models.Using a Revit application programming interface(API),the spatial position and attribute data of the pipe points are extracted from a pipeline database,and the corresponding tubulation data are extracted from a tubulation database.Using the Family class in Revit API,the cluster in the self-built library of pipe point is inserted into the spatial location and the attribute data is added;in the same way,all pipeline instances in the pipeline system are created.The extension and localization of the model accelerated the modeling speed.The system was then used in a real construction project.The expansion of the model database and rapid modeling made the application of BIM technology in three-dimensional visualization of underground pipeline networks more convenient.Furthermore,it has applications in pipeline engineering construction and management. 展开更多
关键词 Building information modeling secondary development underground pipeline 3d modeling visualization.
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Framework system and research flow of uncertainty in 3D geological structure models 被引量:7
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作者 ZHU, Liangfeng ZHUANG, Zhiyi 《Mining Science and Technology》 EI CAS 2010年第2期306-311,共6页
Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error... Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error detection and dynamic correction in 3D geological structure models,we have reviewed the current situation and development trends in 3D geological modeling.The main context of uncertainty in 3D geological structure models is discussed.Major research issues and a general framework system of uncertainty in 3D geological structure models are proposed.We have described in detail the integration of development practices of 3D geological modeling systems,as well as the implementation process for uncertainty evaluation in 3D geological structure models.This study has laid the basis to build theoretical and methodological systems for accuracy assessment and error correction in 3D geological models and can assist in improving 3D modeling techniques under complex geological conditions. 展开更多
关键词 3d geological structure model model quality UNCERTAINTY 3d geological modeling
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Modeling Methods of 3D Model in Digital Twins
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作者 Ruijun Liu Haisheng Li Zhihan Lv 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期985-1022,共38页
To understand the current application and development of 3D modeling in Digital Twins(DTs),abundant literatures on DTs and 3D modeling are investigated by means of literature review.The transition process from 3D mode... To understand the current application and development of 3D modeling in Digital Twins(DTs),abundant literatures on DTs and 3D modeling are investigated by means of literature review.The transition process from 3D modeling to DTs modeling is analyzed,as well as the current application of DTs modeling in various industries.The application of 3D DTs modeling in the􀀀elds of smartmanufacturing,smart ecology,smart transportation,and smart buildings in smart cities is analyzed in detail,and the current limitations are summarized.It is found that the 3D modeling technology in DTs has broad prospects for development and has a huge impact on all walks of life and even human lifestyles.At the same time,the development of DTs modeling relies on the development and support capabilities of mature technologies such as Big Data,Internet of Things,Cloud Computing,Articial Intelligence,and game technology.Therefore,although some results have been achieved,there are still limitations.This work aims to provide a good theoretical support for the further development of 3D DTs modeling. 展开更多
关键词 Digital twins 3d modeling smart manufacturing smart city smart buildings
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3D Modelling of Biological Systems for Biomimetics 被引量:2
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作者 Kevin Hapeshi Ashok K.Bhattacharya 《Journal of Bionic Engineering》 SCIE EI CSCD 2004年第1期20-40,共21页
With the advanced development of computer-based enabling technologies, many engineering, medical, biology, chemistry, physics and food science etc have developed to the unprecedented levels, which lead to many researc... With the advanced development of computer-based enabling technologies, many engineering, medical, biology, chemistry, physics and food science etc have developed to the unprecedented levels, which lead to many research and development interests in various multi-discipline areas. Among them, biomimetics is one of the most promising and attractive branches of study. Biomimetics is a branch of study that uses biological systems as a model to develop synthetic systems. To learn from nature, one of the fundamental issues is to understand the natural systems such animals, insects, plants and human beings etc. The geometrical characterization and representation of natural systems is an important fundamental work for biomimetics research. 3D modeling plays a key role in the geometrical characterization and representation, especially in computer graphical visualization. This paper firstly presents the typical procedure of 3D modelling methods and then reviews the previous work of 3D geometrical modelling techniques and systems developed for industrial, medical and animation applications. Especially the paper discusses the problems associated with the existing techniques and systems when they are applied to 3D modelling of biological systems. Based upon the discussions, the paper proposes some areas of research interests in 3D modelling of biological systems and for Biomimetics. 展开更多
关键词 biomimetics 3d modelling 3d scanners 3d geometry computation biological systems
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3D Model Occlusion Culling Optimization Method Based on WebGPU Computing Pipeline
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作者 Liming Ye Gang Liu +4 位作者 Genshen Chen Kang Li Qiyu Chen Wenyao Fan Junjie Zhang 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期2529-2545,共17页
Nowadays,Web browsers have become an important carrier of 3D model visualization because of their convenience and portability.During the process of large-scale 3D model visualization based on Web scenes with the probl... Nowadays,Web browsers have become an important carrier of 3D model visualization because of their convenience and portability.During the process of large-scale 3D model visualization based on Web scenes with the problems of slow rendering speed and low FPS(Frames Per Second),occlusion culling,as an important method for rendering optimization,can remove most of the occluded objects and improve rendering efficiency.The traditional occlusion culling algorithm(TOCA)is calculated by traversing all objects in the scene,which involves a large amount of repeated calculation and time consumption.To advance the rendering process and enhance rendering efficiency,this paper proposes an occlusion culling with three different optimization methods based on the WebGPU Computing Pipeline.Firstly,for the problem of large amounts of repeated calculation processes in TOCA,these units are moved from the CPU to the GPU for parallel computing,thereby accelerating the calculation of the Potential Visible Sets(PVS);Then,for the huge overhead of creating pipeline caused by too many 3D models in a certain scene,the Breaking Occlusion Culling Algorithm(BOCA)is introduced,which removes some nodes according to building a Hierarchical Bounding Volume(BVH)scene tree to reduce the overhead of creating pipelines;After that,the structure of the scene tree is transmitted to the GPU in the order of depth-first traversal and finally,the PVS is obtained by parallel computing.In the experiments,3D geological models with five different scales from 1:5,000 to 1:500,000 are used for testing.The results show that the proposed methods can reduce the time overhead of repeated calculation caused by the computing pipeline creation and scene tree recursive traversal in the occlusion culling algorithm effectively,with 97%rendering efficiency improvement compared with BOCA,thereby accelerating the rendering process on Web browsers. 展开更多
关键词 WebGPU potential visible set occlusion culling computing pipeline 3d model
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3D Model Construction and Ecological Environment Investigation on a Regional Scale Using UAV Remote Sensing
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作者 Chao Chen Yankun Chen +7 位作者 Haohai Jin Li Chen Zhisong Liu Haozhe Sun Junchi Hong Haonan Wang Shiyu Fang Xin Zhang 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1655-1672,共18页
The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achiev... The acquisition of digital regional-scale information and ecological environmental data has high requirements for structural texture,spatial res-olution,and multiple parameter categories,which is challenging to achieve using satellite remote sensing.Considering the convenient,facilitative,and flexible characteristics of UAV(unmanned air vehicle)remote sensing tech-nology,this study selects a campus as a typical research area and uses the Pegasus D2000 equipped with a D-MSPC2000 multi-spectral camera and a CAM3000 aerial camera to acquire oblique images and multi-spectral data.Using professional software,including Context Capture,ENVI,and ArcGIS,a 3D(three-dimensional)campus model,a digital orthophoto map,and multi-spectral remote sensing map drawing are realized,and the geometric accuracy of typical feature selection is evaluated.Based on a quantitative remote sensing model,the campus ecological environment assessment is performed from the perspectives of vegetation and water body.The results presented in this study could be of great significance to the scientific management and sustainable development of regional natural resources. 展开更多
关键词 Unmanned air vehicle multi-spectral camera oblique photography 3d model construction ecological environment investigation regional scale
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Survey of lightweighting methods of huge 3D models for online Web3D visualization
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作者 Xiaojun LIU Jinyuan JIA Chang LIU 《Virtual Reality & Intelligent Hardware》 EI 2023年第5期395-406,共12页
Background With the rapid development of Web3D technologies, the online Web3D visualization, particularly for complex models or scenes, has been in a great demand. Owing to the major conflict between the Web3D system ... Background With the rapid development of Web3D technologies, the online Web3D visualization, particularly for complex models or scenes, has been in a great demand. Owing to the major conflict between the Web3D system load and resource consumption in the processing of these huge models, the huge 3D model lightweighting methods for online Web3D visualization are reviewed in this paper. Methods By observing the geometry redundancy introduced by man-made operations in the modeling procedure, several categories of light-weighting related work that aim at reducing the amount of data and resource consumption are elaborated for Web3D visualization. Results By comparing perspectives, the characteristics of each method are summarized, and among the reviewed methods, the geometric redundancy removal that achieves the lightweight goal by detecting and removing the repeated components is an appropriate method for current online Web3D visualization. Meanwhile, the learning algorithm, still in improvement period at present, is our expected future research topic. Conclusions Various aspects should be considered in an efficient lightweight method for online Web3D visualization, such as characteristics of original data, combination or extension of existing methods, scheduling strategy, cache man-agement, and rendering mechanism. Meanwhile, innovation methods, particularly the learning algorithm, are worth exploring. 展开更多
关键词 Huge 3d model Lightweighting WEB3d VISUALIZATION Shape descriptor
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3D forward modeling and response characteristics of low-resistivity overburden of the CFS-PML absorbing boundary for ground-well transient electromagnetic method
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作者 Lijuan Zhao Mingzhong Gao +3 位作者 Nengzhong Lei Hongfei Duan Weizhong Qiu Zhaoying Chen 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第12期1541-1550,共10页
This study used the stable and convergent Dufort-Frankel method to differentially discretize the diffusion equation of the ground-well transient electromagnetic secondary field.The absorption boundary condition of com... This study used the stable and convergent Dufort-Frankel method to differentially discretize the diffusion equation of the ground-well transient electromagnetic secondary field.The absorption boundary condition of complex frequency-shifted perfectly matched layer(CFS-PML)was used for truncation so that the low-frequency electromagnetic wave can be better absorbed at the model boundary.A typical three-dimensional(3D)homogeneous half-space model was established and a low-resistivity cube model was analyzed under the half-space condition.The response patterns and drivers of the low-resistivity cube model were discussed under the influence of a low-resistivity overburden.The absorption boundary conditions of CFS-PML significantly affected the low-frequency electromagnetic waves.For a low-resistivity cube around the borehole,its response curve exhibited a single-peak,and the extreme point of the curve corresponded to the center of the low-resistivity body.When the low-resistivity cube was directly below the borehole,the response curve showed three extreme values(two high and one low),with the low corresponding to the center of the low-resistivity body.The total field response of the low-resistivity overburden was stronger than that of the uniform half-space model due to the low-resistivity shielding effect of electromagnetic waves.When the receiving-transmitting distance gradually increased,the effect of the low-resistivity overburden was gradually weakened,and the response of the low-resistivity cube was strengthened.It was affected by the ratio of the overburden resistivity to the resistivity of the low-resistivity body. 展开更多
关键词 Ground-well transient electromagnetic method CFS-PML boundary condition 3d forward modeling Low-resistivity overburden
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3D Modeling and Estimation of the Tonnage of the Granite Quarry of Linguésso (North-West of Côte d’Ivoire) by Electrical Methods
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作者 Yapo Assi Martial Kouame Loukou Nicolas +1 位作者 Aka Ehui Beh Jean Constantin Sombo Boko Celestin 《Journal of Geoscience and Environment Protection》 2023年第3期138-154,共17页
A survey and evaluation was carried out on a potential granitoid quarry site in the locality of Linguésso (North West of Ivory Coast) with the aim of identifying and estimating the quantity of exploitable granite... A survey and evaluation was carried out on a potential granitoid quarry site in the locality of Linguésso (North West of Ivory Coast) with the aim of identifying and estimating the quantity of exploitable granite based on the electrical resistivity methods. The combination of electrical trailing, sounding and tomography techniques allowed the determination of the characteristics of the rock deposit, namely the electrical signature (between 19,259 Ωm and 86,316 Ωm), the extension (N90°), the rooting (between 0 and 45 m) and the fracturing (between N14° and N160°) of the granitic formation sought. The modeling resulted in an estimated mineable rock volume of 2,936,250 m<sup>3</sup> providing a production quantity of 7,927,875 tonnes. 展开更多
关键词 Eelectric Resistivity 3d geoelectric model Granitic Quarry Linguésso Ivory Coast
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基于猪模型和腔镜模拟训练器的3D腔镜系统对比评价
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作者 卢如意 孙静 +3 位作者 金以勒 毛彬 张倩 冯靖祎 《中国医院建筑与装备》 2024年第7期27-32,共6页
基于文献分析、小组讨论、德尔菲法(专家咨询法)等方法,确定了3D腔镜系统评价指标,制定了评价标准及专家评价表,邀请多家医院、多个研究领域的临床专家对品牌A和品牌B两款产品基于猪模型以及腔镜模拟训练器进行对比评价。在该研究样本量... 基于文献分析、小组讨论、德尔菲法(专家咨询法)等方法,确定了3D腔镜系统评价指标,制定了评价标准及专家评价表,邀请多家医院、多个研究领域的临床专家对品牌A和品牌B两款产品基于猪模型以及腔镜模拟训练器进行对比评价。在该研究样本量下,结果显示:在动物实验中品牌A共计25项指标中的24项指标评分结果与品牌B没有显著性差异,在立体感这一指标上显著优于品牌B;在腔镜模拟训练器下,品牌A的视野、清晰度、景深等15项指标的评分结果与品牌B差异无统计学意义,但分辨能力、抗反光能力、图像保真性、视疲劳以及总体印象这5项指标的评分与品牌B差异有统计学意义。该研究采用t检验统计学方法分别对比了在动物实验研究中以及腔镜模拟训练器下,专家对品牌A和品牌B各项指标的评分结果以及参评专家对两款设备的总体表现、景深等方面发表的个人建议,可为企业在设备功能和性能改进方面提供参考。 展开更多
关键词 3d腔镜系统 猪模型 腔镜模拟训练器 医疗设备评价
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Three-dimensional Modeling of Ore-forming Elements and Mineralization Prognosis for the Yechangping Mo Deposit,Henan Province,China
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作者 DING Gaoming JI Genyuan +5 位作者 YAN Guolong XU Yongzhong WANG Kunming XIAO Chun WANG Quanle GUO Dongbao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期736-752,共17页
Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-di... Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-dimensional fine interpolation,analysis of spatial distribution patterns,and extraction of quantitative mineral-seeking markers.The Yechangping molybdenum(Mo)deposit is a significant and extensive porphyry-skarn deposit in the East Qinling-Dabie Mo polymetallic metallogenic belt at the southern margin of the North China Block.Abundant borehole data on oreforming elements underpin deep geochemical predictions.The methodology includes the following steps:(1)Threedimensional geological modeling of the deposit was established.(2)Correlation,cluster,and factor analyses post delineation of mineralization stages and determination of mineral generation sequence to identify(Cu,Pb,Zn,Ag)and(Mo,W,mfe)assemblages.(3)A three-dimensional geochemical block model was constructed for Mo,W,mfe,Cu,Zn,Pb,and Ag using the ordinary kriging method,and the variational function was developed.(4)Spatial distribution and enrichment characteristics analysis of ore-forming elements are performed to extract geological information,employing the variogram and w(Cu+Pb+Zn+Ag)/w(Mo+W)as predictive indicators.(5)Identifying the western,northwestern,and southwestern areas of the mine with limited mineralization potential,contrasted by the northeastern and southeastern areas favorable for mineral exploration. 展开更多
关键词 3d geochemical model ore-forming elements GEOSTATISTICS deep mineralization prediction Yechangping Mo deposit
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3D打印技术在舰船管系三维建模设计中的应用
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作者 王晓橹 《舰船科学技术》 北大核心 2024年第6期165-168,共4页
为提升复杂结构舰船管系的设计灵活性,研究3D打印技术在舰船管系三维建模设计中的应用。利用CAD软件建立舰船管系的二维模型,依据舰船管系三角面片的交线段,确定舰船管系的点、线、面关系,将其转换为舰船管系三维模型。将舰船管系三维模... 为提升复杂结构舰船管系的设计灵活性,研究3D打印技术在舰船管系三维建模设计中的应用。利用CAD软件建立舰船管系的二维模型,依据舰船管系三角面片的交线段,确定舰船管系的点、线、面关系,将其转换为舰船管系三维模型。将舰船管系三维模型,导入切片软件中,利用切片引擎运行3D打印切片引擎增强处理算法,切片处理舰船管系三维模型,输出舰船管系三维模型的Gcode代码文件。将Gcode代码导入3D打印机,采用Z字填充法填充舰船管系3D打印材料,实现舰船管系模型的3D打印。实验结果表明,该方法可以精准打印舰船管系三维模型,打印结果的尺寸偏差小,提升了舰船管系设计的灵活性。 展开更多
关键词 3d打印技术 舰船管系 三维建模设计 三角面片 切片引擎 Z字填充法
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Advancing Wound Filling Extraction on 3D Faces:An Auto-Segmentation and Wound Face Regeneration Approach
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作者 Duong Q.Nguyen Thinh D.Le +2 位作者 Phuong D.Nguyen Nga T.K.Le H.Nguyen-Xuan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2197-2214,共18页
Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical applications.In this paper,we propose an efficient approach for automating 3D facial wound seg... Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical applications.In this paper,we propose an efficient approach for automating 3D facial wound segmentation using a two-stream graph convolutional network.Our method leverages the Cir3D-FaIR dataset and addresses the challenge of data imbalance through extensive experimentation with different loss functions.To achieve accurate segmentation,we conducted thorough experiments and selected a high-performing model from the trainedmodels.The selectedmodel demonstrates exceptional segmentation performance for complex 3D facial wounds.Furthermore,based on the segmentation model,we propose an improved approach for extracting 3D facial wound fillers and compare it to the results of the previous study.Our method achieved a remarkable accuracy of 0.9999993% on the test suite,surpassing the performance of the previous method.From this result,we use 3D printing technology to illustrate the shape of the wound filling.The outcomes of this study have significant implications for physicians involved in preoperative planning and intervention design.By automating facial wound segmentation and improving the accuracy ofwound-filling extraction,our approach can assist in carefully assessing and optimizing interventions,leading to enhanced patient outcomes.Additionally,it contributes to advancing facial reconstruction techniques by utilizing machine learning and 3D bioprinting for printing skin tissue implants.Our source code is available at https://github.com/SIMOGroup/WoundFilling3D. 展开更多
关键词 3d printing technology face reconstruction 3d segmentation 3d printed model
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The Method and Practice of Constructing 3D Geological Model from Coalfield Exploration 2D Maps
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作者 Hui Su Qingyuan Li +4 位作者 Duohu Hao Ke Xiong Wei Hu Xinyong Wei Xuan Zhang 《International Journal of Geosciences》 2023年第7期635-654,共20页
3D geological modeling is an inevitable choice for coal exploration to adapt to the transformation of coal mining for green, fine, transparent and Intelligent mining. In the traditional Coalfield exploration geologica... 3D geological modeling is an inevitable choice for coal exploration to adapt to the transformation of coal mining for green, fine, transparent and Intelligent mining. In the traditional Coalfield exploration geological reports, the spatial expression form for the coal seams and their surrounding rocks are 2D maps. These 2D maps are excellent data sources for constructing 3D geological models of coal field exploration areas. How to construct 3D models from these 2D maps has been studying in coal exploration industry for a long time, and still no breakthrough has been achieved so far. This paper discusses the principle, method and software design idea of constructing 3D geological model of an exploration area with 2D maps made by AutoCAD/MapGIS. At first, the paper analyzes 3D geological surface expression mode in 3D geological modeling software. It is pointed out that although contour method has unique advantages in coal field exploration, TIN (Triangular Irregular Network) is still the standard configuration of 3D modeling software for coal field. Then, the paper discusses the method of 2D line features obtaining elevation and upgrading 2D curve to 3D curve. Next, the method of semi-automatic partition is introduced to build the boundary ring of the surface patch, that is, the user clicks and selects the line feature to build the outer boundary ring of the surface patch. Then, Auto-process method for fault line inside of the outer boundary ring is discussed, it including construction of fault ring, determining fault ring being normal fault ring or reverse fault ring and an algorithm of dealing with normal fault ring. An algorithm of dealing with reverse fault ring is discussed detailly, the method of expanding reverse fault ring and dividing the duplicate area in reverse fault into two portions is introduced. The paper also discusses the method of extraction ridge line/valley line, the construction of fault plane, the construction of stratum and coal body. The above ideas and methods have been initially implemented in the “3D modeling platform for coal field exploration” software, and applied to the 3D modeling practice of data from several coal field exploration areas in Ningxia, Shanxi, Qinghai, etc. 展开更多
关键词 Coalfield Exploration 3d Geological modeling Semi-Automatic Partition Partition Triangulation Reverse Fault Duplicate Area Triangulation
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Numerical three-dimensional modeling of earthen dam piping failure
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作者 Zhengang Wang 《Water Science and Engineering》 EI CAS CSCD 2024年第1期72-82,共11页
A physically-based numerical three-dimensional earthen dam piping failure model is developed for homogeneous and zoned soil dams.This model is an erosion model,coupled with force/moment equilibrium analyses.Orifice fl... A physically-based numerical three-dimensional earthen dam piping failure model is developed for homogeneous and zoned soil dams.This model is an erosion model,coupled with force/moment equilibrium analyses.Orifice flow and two-dimensional(2D)shallow water equations(SWE)are solved to simulate dam break flows at different breaching stages.Erosion rates of different soils with different construction compaction efforts are calculated using corresponding erosion formulae.The dam's real shape,soil properties,and surrounding area are programmed.Large outer 2D-SWE grids are used to control upstream and downstream hydraulic conditions and control the boundary conditions of orifice flow,and inner 2D-SWE flow is used to scour soil and perform force/moment equilibrium analyses.This model is validated using the European Commission IMPACT(Investigation of Extreme Flood Processes and Uncertainty)Test#5 in Norway,Teton Dam failure in Idaho,USA,and Quail Creek Dike failure in Utah,USA.All calculated peak outflows are within 10%errors of observed values.Simulation results show that,for a V-shaped dam like Teton Dam,a piping breach location at the abutment tends to result in a smaller peak breach outflow than the piping breach location at the dam's center;and if Teton Dam had broken from its center for internal erosion,a peak outflow of 117851 m'/s,which is 81%larger than the peak outflow of 65120 m3/s released from its right abutment,would have been released from Teton Dam.A lower piping inlet elevation tends to cause a faster/earlier piping breach than a higher piping inlet elevation. 展开更多
关键词 3d dam breach model 2D shallow water equations 3d slope stability analysis Piping failure Teton Dam Quail Creek Dike
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