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Evaluation of Maxillary Dental Arch Widths in Individuals Having Unilateral and Bilateral Cleft Lip and Palate Using Three-Dimensional Digital Models
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作者 Ege Dogan Abdü +2 位作者 lkadir Iş ik Servet Dogan 《Open Journal of Stomatology》 2019年第7期159-167,共9页
Aim: Maxillary dental arch widths were evaluated in individuals having unilateral (UCLP) and bilateral (BCLP) cleft lip and palate (CLP) using three-dimensional (3D) digital models. Material and Method: The study had ... Aim: Maxillary dental arch widths were evaluated in individuals having unilateral (UCLP) and bilateral (BCLP) cleft lip and palate (CLP) using three-dimensional (3D) digital models. Material and Method: The study had been conducted on 80 individuals aged between 14 - 17 years having UCLP and BCLP. 40 of the individuals had UCLP, whereas 40 had BCLP. The maxillary dental models taken from patients before the treatment were scanned using Orthomodel Programme (v.1.01, Orthomodel Inc., Istanbul, Turkey) to obtain 3D imagery. Student’s t-test was used in order to assess the data obtained by using SPSS software version 22.0. Results: In BCLP, the average inter-canine distance was 17.44 ± 1.31 mm, the average inter-molar distance was 36.57 ± 1.12 mm, while inter-canine/inter-molar ratio was 0.47. Whereas in UCLP, it was 25.10 ± 0.63 mm, 42.20 ± 0.53 mm and 0.59. The inter-canine distance in UCLP was found to be large enough to be statistically significant (p 0.05), even though there were differences in inter-molar widths. Conclusion: For the stable orthodontic treatment results, one of the most important points is arch form and widths to be coherent with each other. In our study, the increase of inter-canine distance seen in UCLP indicates that in the cleft region, the maxillary arch is inclined over to the back, while the same situation in BCLP suggests that the maxillary segments are collapsed inside. The difference in the arch is highly affected by the primary surgical treatment. 展开更多
关键词 UNILATERAL CLEFT LIP and PALATE Bilateral CLEFT LIP and PALATE three-dimensional digital models
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Measurement Problem of Enterprise Digital Transformation:New Methods and Findings Based on Large Language Models
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作者 Jin Xingye Zuo Congjiang +2 位作者 Fang Mingyue Li Tao Nie Huihua 《China Economist》 2025年第2期70-95,共26页
Despite broad consensus on the importance of enterprise digital transformation,significant discrepancies persist regarding its actual effects.This divergence stems primarily from two key measurement challenges:(1)a la... Despite broad consensus on the importance of enterprise digital transformation,significant discrepancies persist regarding its actual effects.This divergence stems primarily from two key measurement challenges:(1)a lack of clear and consistent definitions of enterprise digital transformation,and(2)a lack of rigorous and accurate measurement methodologies.These shortcomings lead to research findings that are incomparable,difficult to replicate,and often conflicting.To effectively address the aforementioned challenges,this paper employs machine learning and large language models(LLMs)to construct a novel set of indicators for enterprise digital transformation.The work begins by manually annotating sentences from annual reports of listed companies in China from 2006 to 2020.These labeled sentences are then used to train and fine-tune several machine learning models,including LLMs.The ERNIE model,demonstrating the best classification performance among the models tested,is selected as the sentence classifier to predict sentence labels across the full text of the annual reports,ultimately constructing the enterprise digital transformation metrics.Both theoretical analysis and multiple data cross-validations demonstrate that the metrics developed in this paper are more accurate than existing approaches.Based on these metrics,the paper empirically examines the impact of enterprise digital transformation on financial performance.Our findings reveal three key points:(1)enterprise digital transformation significantly enhances financial performance,with big data,AI,mobile internet,cloud computing,and the Internet of Things(IoT)all playing a significant role;however,blockchain technology does not show a significant effect;(2)the significant positive effect of digital transformation on financial performance is primarily observed in firms with weaker initial financial performance;and(3)enterprise digital transformation improves financial performance mainly through enhancing efficiency and reducing costs.This research has practical implications for promoting enterprise digital transformation and fostering high-quality economic development. 展开更多
关键词 Enterprise digital transformation digital economy digital technology AI large language models(LLMs)
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Real-time model updating and prediction of three-dimensional timevarying consolidation settlement using machine learning
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作者 Huaming Tian Yu Wang Danni Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第9期5954-5969,共16页
The development of digital twins for geotechnical structures necessitates the real-time updates of threedimensional(3D)virtual models(e.g.numerical finite element method(FEM)model)to accurately predict time-varying ge... The development of digital twins for geotechnical structures necessitates the real-time updates of threedimensional(3D)virtual models(e.g.numerical finite element method(FEM)model)to accurately predict time-varying geotechnical responses(e.g.consolidation settlement)in a 3D spatial domain.However,traditional 3D numerical model updating approaches are computationally prohibitive and therefore difficult to update the 3D responses in real time.To address these challenges,this study proposes a novel machine learning framework called sparse dictionary learning(T-3D-SDL)for real-time updating of time-varying 3D geotechnical responses.In T-3D-SDL,a concerned dataset(e.g.time-varying 3D settlement)is approximated as a linear superposition of dictionary atoms generated from 3D random FEM analyses.Field monitoring data are then used to identify non-trivial atoms and estimate their weights within a Bayesian framework for model updating and prediction.The proposed approach enables the real-time update of temporally varying settlements with a high 3D spatial resolution and quantified uncertainty as field monitoring data evolve.The proposed approach is illustrated using an embankment construction project.The results show that the proposed approach effectively improves settlement predictions along temporal and 3D spatial dimensions,with minimal latency(e.g.within minutes),as monitoring data appear.In addition,the proposed approach requires only a reasonably small number of 3D FEM model evaluations,avoids the use of widely adopted yet often criticized surrogate models,and effectively addresses the limitations(e.g.computational inefficiency)of existing 3D model updating approaches. 展开更多
关键词 digital twin three-dimensional(3D)finite element method(FEM) Time-varying 3D settlement Real-time model update Sparse dictionary learning(SDL)
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Development of a Digital Model of a Gear Rotor System for Fault Diagnosis Using the Finite Element Method and Machine Learning
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作者 Anubhav Srivastava Rajiv Tiwari 《Journal of Dynamics, Monitoring and Diagnostics》 2025年第2期121-136,共16页
Geared-rotor systems are critical components in mechanical applications,and their performance can be severely affected by faults,such as profile errors,wear,pitting,spalling,flaking,and cracks.Profile errors in gear t... Geared-rotor systems are critical components in mechanical applications,and their performance can be severely affected by faults,such as profile errors,wear,pitting,spalling,flaking,and cracks.Profile errors in gear teeth are inevitable in manufacturing and subsequently accumulate during operations.This work aims to predict the status of gear profile deviations based on gear dynamics response using the digital model of an experimental rig setup.The digital model comprises detailed CAD models and has been validated against the expected physical behavior using commercial finite element analysis software.The different profile deviations are then modeled using gear charts,and the dynamic response is captured through simulations.The various features are then obtained by signal processing,and various ML models are then evaluated to predict the fault/no-fault condition for the gear.The best performance is achieved by an artificial neural network with a prediction accuracy of 97.5%,which concludes a strong influence on the dynamics of the gear rotor system due to profile deviations. 展开更多
关键词 digital model finite element modeling gear profile errors geared-rotor system machine learning
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Three-Dimensional Prospectivity Modeling of Jinshan Ag-Au Deposit,Southern China by Weights-of-Evidence
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作者 Fan Xiao Qiuming Cheng +1 位作者 Weisheng Hou Frederik P.Agterberg 《Journal of Earth Science》 2025年第5期2038-2057,共20页
To comprehensively utilize the valuable geological map,exploration profile,borehole,and geochemical logging data and the knowledge on the formation of the Jinshan Ag-Au deposit for forecasting the exploration targets ... To comprehensively utilize the valuable geological map,exploration profile,borehole,and geochemical logging data and the knowledge on the formation of the Jinshan Ag-Au deposit for forecasting the exploration targets of concealed ore bodies,three-dimensional Mineral Prospectivity Modeling(MPM)of the deposit has been conducted using the weights-of-evidence(WofE)method.Conditional independence between evidence layers was tested,and the outline results using the prediction-volume(P-V)and Student's t-statistic methods for delineating favorable mineralization areas from continuous posterior probability map were critically compared.Four exploration targets delineated ultimately by the Student's t-statistic method for the discovery of minable ore bodies in each of the target areas were discussed in detail.The main conclusions include:(1)three-dimensional modeling of a deposit using multi-source reconnaissance data is useful for MPM in interpreting their relationships with known ore bodies;(2)WofE modeling can be used as a straightforward tool for integrating deposit model and reconnaissance data in MPM;(3)the Student's t-statistic method is more applicable in binarizing the continuous prospectivity map for exploration targeting than the PV approach;and(4)two target areas within high potential to find undiscovered ore bodies were diagnosed to guide future near-mine exploration activities of the Jinshan deposit. 展开更多
关键词 three-dimensional modeling mineral prospectivity mapping exploration targeting WEIGHTS-OF-EVIDENCE C-V fractal model Jinshan Ag-Au deposit mineral deposits economic geology
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Research on the Digital Transformation of Corporate Finance Based on the Shared Services Model
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作者 Chenyue Xu 《Proceedings of Business and Economic Studies》 2025年第2期127-133,共7页
Against the backdrop of the rapid development of the digital economy,corporate financial management faces unprecedented challenges and opportunities.This paper will start with the concept of financial shared services ... Against the backdrop of the rapid development of the digital economy,corporate financial management faces unprecedented challenges and opportunities.This paper will start with the concept of financial shared services to deeply explore the role and significance of the financial shared service model in the digital transformation of corporate finance.It analyzes the existing problems in the current process of digital transformation of corporate finance and proposes corresponding solutions,providing valuable references and guidance for enterprises to achieve digital transformation of finance. 展开更多
关键词 Financial sharing Service model Corporate finance digital transformation
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Mixed integer programming modeling for the satellite three-dimensional component assignment and layout optimization problem
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作者 Yufeng XIA Xianqi CHEN +3 位作者 Zhijia LIU Weien ZHOU Wen YAO Zhongneng ZHANG 《Chinese Journal of Aeronautics》 2025年第6期427-447,共21页
Satellite Component Layout Optimization(SCLO) is crucial in satellite system design.This paper proposes a novel Satellite Three-Dimensional Component Assignment and Layout Optimization(3D-SCALO) problem tailored to en... Satellite Component Layout Optimization(SCLO) is crucial in satellite system design.This paper proposes a novel Satellite Three-Dimensional Component Assignment and Layout Optimization(3D-SCALO) problem tailored to engineering requirements, aiming to optimize satellite heat dissipation while considering constraints on static stability, 3D geometric relationships between components, and special component positions. The 3D-SCALO problem is a challenging bilevel combinatorial optimization task, involving the optimization of discrete component assignment variables in the outer layer and continuous component position variables in the inner layer,with both influencing each other. To address this issue, first, a Mixed Integer Programming(MIP) model is proposed, which reformulates the original bilevel problem into a single-level optimization problem, enabling the exploration of a more comprehensive optimization space while avoiding iterative nested optimization. Then, to model the 3D geometric relationships between components within the MIP framework, a linearized 3D Phi-function method is proposed, which handles non-overlapping and safety distance constraints between cuboid components in an explicit and effective way. Subsequently, the Finite-Rectangle Method(FRM) is proposed to manage 3D geometric constraints for complex-shaped components by approximating them with a finite set of cuboids, extending the applicability of the geometric modeling approach. Finally, the feasibility and effectiveness of the proposed MIP model are demonstrated through two numerical examples"and a real-world engineering case, which confirms its suitability for complex-shaped components and real engineering applications. 展开更多
关键词 Mixed integer programming modeling three-dimensional component assignment Layout optimization Phi-function Finite-rectangle method
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Research on the Application of Digital Modeling Technology in Nixing Pottery from the Perspective of Maker Education Theory
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作者 Jiaqing Lyu Xue Bai Zhi Liao 《Journal of Contemporary Educational Research》 2025年第7期152-157,共6页
In the context of global digital transformation and the rising prominence of maker education,this study explores the innovative integration of digital modeling technologies with traditional Nixing Pottery craftsmanshi... In the context of global digital transformation and the rising prominence of maker education,this study explores the innovative integration of digital modeling technologies with traditional Nixing Pottery craftsmanship.By constructing a teaching framework under maker education theory,the research investigates how 3D modeling,CAD design,and 3D printing technologies can empower learners to address challenges in cultural heritage preservation and artistic innovation.Through experimental teaching and case analysis,the study verifies that this integrated approach significantly enhances learners’digital literacy,creative thinking,and cultural identity while optimizing Nixing Pottery’s production processes and design possibilities.The findings contribute to theoretical models of technology-enhanced craft education and provide practical pathways for the digital transformation of intangible cultural heritage. 展开更多
关键词 Maker education theory digital modeling technology Nixing Pottery Educational innovation Cultural heritage digitization 3D printing Cross-disciplinary education Artisan revitalization
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Special Topic on Digital Twin Online Channel Modeling for 6G and Beyond
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作者 WANG Chengxiang HUANG Chen 《ZTE Communications》 2025年第2期1-2,共2页
Channel characterization and modeling are fundamental to communication system design,development,testing,and deployment.As the innate digital twins of wireless channels,channel models replicate real-world channel beha... Channel characterization and modeling are fundamental to communication system design,development,testing,and deployment.As the innate digital twins of wireless channels,channel models replicate real-world channel behaviors,e.g.,large-scale/small-scale fading,spatio-temporal-frequency non-stationarity,through mathematical and data-driven methods.This enables simulation-based validation across system development stages—from protocol design to network optimization-without costly physical testing. 展开更多
关键词 simulation G VALIDATION communication system channel modeling channel characterization digital twin protocol design
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Current Situation of Urban Energy Consumption Under the Digital Economy Model
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作者 Yun Huang Tao Qian 《Proceedings of Business and Economic Studies》 2025年第6期1-6,共6页
The digital economy has injected continuous momentum into the development of urban economy and plays a positive and important role in the transformation and upgrading of urban energy consumption.Specifically,the digit... The digital economy has injected continuous momentum into the development of urban economy and plays a positive and important role in the transformation and upgrading of urban energy consumption.Specifically,the digital economy can significantly improve the efficiency of urban energy consumption by virtue of its distinctive characteristics of low pollution and high efficiency.Moreover,empowered by the digital economy,the pace of transformation and upgrading of high-pollution traditional industries has been accelerated.Particularly importantly,the urban energy consumption structure has been optimized and adjusted through the indirect role of intermediate factors.From this perspective,studying the current situation and countermeasures of urban energy consumption under the digital economy holds important practical significance both in theory and practice.This paper first briefly summarizes the relevant literature on the impact of the digital economy on the energy consumption structure;then,it focuses on detailed data to explore the current situation of urban energy consumption under the digital economy model;finally,based on the summary of the current situation,it puts forward practical and feasible suggestions,hoping to provide a decision-making basis for the implementation of policies in different types of cities and offer innovative ideas for promoting the high-quality development of urban energy systems. 展开更多
关键词 Current situation digital economy model Suggestions Urban energy consumption
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Research on the Optimization of Digital Technology-Based Higher Education Teaching Models
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作者 Yuanwei Zhao 《Journal of Contemporary Educational Research》 2025年第6期100-105,共6页
With the advancement of digital technology,new technologies such as artificial intelligence,big data,and cloud computing have gradually permeated higher education,leading to fundamental changes in teaching and learnin... With the advancement of digital technology,new technologies such as artificial intelligence,big data,and cloud computing have gradually permeated higher education,leading to fundamental changes in teaching and learning methods.Therefore,in the process of reforming and developing higher education,it is essential to take digital technology empowering the optimization of the education industry as a breakthrough,focusing on five key areas:the construction of smart classrooms,the digital integration of teaching resources,the development of personalized learning support systems,the reform of online-offline hybrid teaching,and the intelligentization of educational management.This paper also examines the experiences,challenges,and shortcomings of typical universities in using digital technology to improve teaching quality,optimize resource allocation,and innovate teaching management models.Finally,corresponding countermeasures and suggestions are proposed to facilitate the smooth implementation of digital transformation in higher education institutions. 展开更多
关键词 digital technology Higher education Teaching model optimization Smart classroom Hybrid teaching
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A Synergistic Management Framework Integrating Building Information Modeling and Digital Twins in Large-Scale Complex Construction Projects
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作者 Longyan Tian 《Journal of World Architecture》 2025年第5期44-50,共7页
The management of large-scale architectural engineering projects(e.g.,airports,hospitals)is plagued by information silos,cost overruns,and scheduling delays.While building information modeling(BIM)has improved 3D desi... The management of large-scale architectural engineering projects(e.g.,airports,hospitals)is plagued by information silos,cost overruns,and scheduling delays.While building information modeling(BIM)has improved 3D design coordination,its static nature limits its utility in real-time construction management and operational phases.This paper proposes a novel synergistic framework that integrates the static,deep data of BIM with the dynamic,real-time capabilities of digital twin(DT)technology.The framework establishes a closed-loop data flow from design(BIM)to construction(IoT,drones,BIM 360)to operation(DT platform).We detail the technological stack required,including IoT sensors,cloud computing,and AI-driven analytics.The application of this framework is illustrated through a simulated case study of a mega-terminal airport construction project,demonstrating potential reductions in rework by 15%,improvement in labor productivity by 10%,and enhanced predictive maintenance capabilities.This research contributes to the field of construction engineering by providing a practical model for achieving full lifecycle digitalization and intelligent project management. 展开更多
关键词 Building information modeling digital twin Construction management Internet of Things
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Artificial intelligence-aided semi-automatic joint trace detection from textured three-dimensional models of rock mass
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作者 Seyedahmad Mehrishal Jineon Kim +1 位作者 Yulong Shao Jae Joon Song 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期1973-1985,共13页
It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimens... It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimensional(3D)models are relatively straightforward but time-consuming.One potential solution to enhance this process is to use machine learning algorithms to detect the 3D traces.In this study,a unique pixel-wise texture mapper algorithm generates a dense point cloud representation of an outcrop with the precise resolution of the original textured 3D model.A virtual digital image rendering was then employed to capture virtual images of selected regions.This technique helps to overcome limitations caused by the surface morphology of the rock mass,such as restricted access,lighting conditions,and shading effects.After AI-powered trace detection on two-dimensional(2D)images,a 3D data structuring technique was applied to the selected trace pixels.In the 3D data structuring,the trace data were structured through 2D thinning,3D reprojection,clustering,segmentation,and segment linking.Finally,the linked segments were exported as 3D polylines,with each polyline in the output corresponding to a trace.The efficacy of the proposed method was assessed using a 3D model of a real-world case study,which was used to compare the results of artificial intelligence(AI)-aided and human intelligence trace detection.Rosette diagrams,which visualize the distribution of trace orientations,confirmed the high similarity between the automatically and manually generated trace maps.In conclusion,the proposed semi-automatic method was easy to use,fast,and accurate in detecting the dominant jointing system of the rock mass. 展开更多
关键词 Automatic trace detection digital joint mapping Rock discontinuities characterization three-dimensional(3D)trace network
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Research on the Teaching Reform Path of Digital Empowerment for Business Model Innovation from the Perspective of Ideological and Political Education in Courses
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作者 Ling Peng Xiong Deng +1 位作者 Zhenfeng Zhu Lina Peng 《Journal of Contemporary Educational Research》 2025年第6期72-79,共8页
Under the dual impetus of the fundamental task of“cultivating virtue and nurturing talent”and the national strategy of digitalizing education,promoting the deep integration of ideological and political education in ... Under the dual impetus of the fundamental task of“cultivating virtue and nurturing talent”and the national strategy of digitalizing education,promoting the deep integration of ideological and political education in courses with digital technology has become a core issue in the curriculum reform of colleges and universities.This paper takes the course“Business Model Innovation”as the research object and focuses on the problems existing in the current course,such as lagging content update,superficial application of digital tools,and weakening elements of ideological and political education.This paper proposes a teaching reform path that is supported by digital means and centered on value guidance,and focuses on how to systematically optimize teaching content design,interactive teaching scenarios,evaluation and feedback mechanisms,and teacher collaboration systems through specific tools such as“Rain Classroom,”“Enterprise Sand Table,”and“Smart Classroom Platform.”We aim to build a digital model of ideological and political education in the curriculum that integrates knowledge imparting,ability training,and value shaping,and to provide practical reference and path support for the cultivation of high-quality business talents in the new era. 展开更多
关键词 Course-based ideological and political education Business model innovation digital empowerment Teaching reform Blended learning
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Characteristics of Channel Sand Body Based on 3D Digital Outcrop Model:A Case Study of Shaximiao Formation Outcrop,in Sichuan Basin,China
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作者 Xianghui Zhang Changmin Zhang +3 位作者 Wei Yang Wenjun Fu Zhihong Wang Qinghai Xu 《Journal of Earth Science》 2025年第4期1766-1779,共14页
To address the shortage of characterization scale of field outcrops,we used the characteristics of unmanned aerial vehicle(UAV)oblique photography with a wide field of view and a high degree of quantification for imag... To address the shortage of characterization scale of field outcrops,we used the characteristics of unmanned aerial vehicle(UAV)oblique photography with a wide field of view and a high degree of quantification for image acquisition,data processing,and geological interpretation of the outcrops of the Shaximiao Formation in the Sichuan Basin.We established a 3D digital outcrop model(DOM),which combines the advantages of visualization and digitization the 3D DOM to interpret the characteristics of typical channel sand bodies.Within the study area,we have identified three types of channel deposition:composite channel deposition,crevasse channel deposition,and abandoned channel deposition.Among these,the composite channel deposition was mainly sandstone,the bottom contains conglomerate,with large cross-bedding,and the maximum thickness of the single sand body was 1.96 m.The crevasse channel deposition was mainly fine sandstone and siltstone,with massive bedding and small cross-bedding,and the maximum thickness of the single sand body was 0.64 m.The abandoned channel deposition dominated by mudstone with thin sandstone,the sandstone was mainly lenticular in section,and the maximum thickness of the single sand body was 0.28 m.We identified the depositional model of the studied region,which is dominated by braided river deposition,based on the growth size and correspondence of the sand bodies.The research provides a comparative foundation for the detailed characterisation of the underground reservoir sands found in the Jurassic Shaximiao Formation in the Sichuan Basin.It also serves as a reference for the effective study of UAV oblique photography technology in the field. 展开更多
关键词 unmanned aerial vehicle oblique photography digital outcrop model channel sand body Shaximiao Formation Sichuan Basin
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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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Three-Dimensional TIN Algorithm for Digital Terrain Modeling 被引量:7
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作者 ZHU Qing ZHANG Yeting LI Fengchun 《Geo-Spatial Information Science》 2008年第2期79-85,共7页
The problem of taking an unorganized point cloud in 3D space and fitting a polyhedral surface to those points is both important and difficult. Aiming at increasing applications of full three dimensional digital terrai... The problem of taking an unorganized point cloud in 3D space and fitting a polyhedral surface to those points is both important and difficult. Aiming at increasing applications of full three dimensional digital terrain surface modeling, a new algorithm for the automatic generation of three dimensional triangulated irregular network from a point cloud is pro- posed. Based on the local topological consistency test, a combined algorithm of constrained 3D Delaunay triangulation and region-growing is extended to ensure topologically correct reconstruction. This paper also introduced an efficient neighbor- ing triangle location method by making full use of the surface normal information. Experimental results prove that this algo- rithm can efficiently obtain the most reasonable reconstructed mesh surface with arbitrary topology, wherein the automati- cally reconstructed surface has only small topological difference from the true surface. This algorithm has potential applica- tions to virtual environments, computer vision, and so on. 展开更多
关键词 three dimensional triangulated irregular network digital terrain surface modeling Delaunay triangulation
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From Digital Human Modeling to Human Digital Twin: Framework and Perspectives in Human Factors 被引量:1
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作者 Qiqi He Li Li +5 位作者 Dai Li Tao Peng Xiangying Zhang Yincheng Cai Xujun Zhang Renzhong Tang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期1-14,共14页
The human digital twin(HDT)emerges as a promising human-centric technology in Industry 5.0,but challenges remain in human modeling and simulation.Digital human modeling(DHM)provides solutions for modeling and simulati... The human digital twin(HDT)emerges as a promising human-centric technology in Industry 5.0,but challenges remain in human modeling and simulation.Digital human modeling(DHM)provides solutions for modeling and simulating human physical and cognitive aspects to support ergonomic analysis.However,it has limitations in real-time data usage,personalized services,and timely interaction.The emerging HDT concept offers new possibilities by integrating multi-source data and artificial intelligence for continuous monitoring and assessment.Hence,this paper reviews the evolution from DHM to HDT and proposes a unified HDT framework from a human factors perspective.The framework comprises the physical twin,the virtual twin,and the linkage between these two.The virtual twin integrates human modeling and AI engines to enable model-data-hybrid-enabled simulation.HDT can potentially upgrade traditional ergonomic methods to intelligent services through real-time analysis,timely feedback,and bidirectional interactions.Finally,the future perspectives of HDT for industrial applications as well as technical and social challenges are discussed.In general,this study outlines a human factors perspective on HDT for the first time,which is useful for cross-disciplinary research and human factors innovation to enhance the development of HDT in industry. 展开更多
关键词 Human digital twin digital human modeling Human factors Human-centric technology
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Oxygen tension modulates cell function in an in vitro three-dimensional glioblastoma tumor model 被引量:1
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作者 Sen Wang Siqi Yao +8 位作者 Na Pei Luge Bai Zhiyan Hao Dichen Li Jiankang He J.Miguel Oliveira Xiaoyan Xue Ling Wang Xinggang Mao 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第3期307-319,共13页
Hypoxia is a typical feature of the tumor microenvironment,one of the most critical factors affecting cell behavior and tumor progression.However,the lack of tumor models able to precisely emulate natural brain tumor ... Hypoxia is a typical feature of the tumor microenvironment,one of the most critical factors affecting cell behavior and tumor progression.However,the lack of tumor models able to precisely emulate natural brain tumor tissue has impeded the study of the effects of hypoxia on the progression and growth of tumor cells.This study reports a three-dimensional(3D)brain tumor model obtained by encapsulating U87MG(U87)cells in a hydrogel containing type I collagen.It also documents the effect of various oxygen concentrations(1%,7%,and 21%)in the culture environment on U87 cell morphology,proliferation,viability,cell cycle,apoptosis rate,and migration.Finally,it compares two-dimensional(2D)and 3D cultures.For comparison purposes,cells cultured in flat culture dishes were used as the control(2D model).Cells cultured in the 3D model proliferated more slowly but had a higher apoptosis rate and proportion of cells in the resting phase(G0 phase)/gap I phase(G1 phase)than those cultured in the 2D model.Besides,the two models yielded significantly different cell morphologies.Finally,hypoxia(e.g.,1%O2)affected cell morphology,slowed cell growth,reduced cell viability,and increased the apoptosis rate in the 3D model.These results indicate that the constructed 3D model is effective for investigating the effects of biological and chemical factors on cell morphology and function,and can be more representative of the tumor microenvironment than 2D culture systems.The developed 3D glioblastoma tumor model is equally applicable to other studies in pharmacology and pathology. 展开更多
关键词 HYPOXIA GLIOMA three-dimensional glioma model In vitro
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Research Progress in Predictive Maintenance of Offshore Platform Structures Based on Digital Twin Technology
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作者 Jincheng Sha Jiancheng Leng +2 位作者 Houbin Mao Jinyuan Pei Kaixin Diao 《哈尔滨工程大学学报(英文版)》 2025年第5期877-899,共23页
Offshore platforms are large,complex structures designed for long-term service,and they are characterized by high risk and significant investment.Ensuring the safety and reliability of in-service offshore platforms re... Offshore platforms are large,complex structures designed for long-term service,and they are characterized by high risk and significant investment.Ensuring the safety and reliability of in-service offshore platforms requires intelligent operation and maintenance strategies.Digital twin technology can enable the accurate description and prediction of changes in the platform’s physical state through real-time monitoring data.This technology is expected to revolutionize the maintenance of existing offshore platform structures.A digital twin system is proposed for real-time assessment of structural health,prediction of residual life,formulation of maintenance plans,and extension of service life through predictive maintenance.The system integrates physical entities,digital models,intelligent predictive maintenance tools,a visualization platform,and interconnected modules to provide a comprehensive and efficient maintenance framework.This paper examines the current development status of core technologies in physical entity monitoring,digital model construction,and intelligent predictive maintenance.It also outlines future directions for the advancement of these technologies within the digital twin system,offering technical insights and practical references to support further research and applications of digital twin technology in offshore platform structures. 展开更多
关键词 Offshore platform digital twin Physical entity monitoring digital model construction Predictive maintenance
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