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Large-scale model testing of high-pressure grouting reinforcement for bedding slope with rapid-setting polyurethane 被引量:2
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作者 ZHANG Zhichao TANG Xuefeng +2 位作者 LIU Kan YE Longzhen HE Xiang 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3083-3093,共11页
Bedding slope is a typical heterogeneous slope consisting of different soil/rock layers and is likely to slide along the weakest interface.Conventional slope protection methods for bedding slopes,such as retaining wal... Bedding slope is a typical heterogeneous slope consisting of different soil/rock layers and is likely to slide along the weakest interface.Conventional slope protection methods for bedding slopes,such as retaining walls,stabilizing piles,and anchors,are time-consuming and labor-and energy-intensive.This study proposes an innovative polymer grout method to improve the bearing capacity and reduce the displacement of bedding slopes.A series of large-scale model tests were carried out to verify the effectiveness of polymer grout in protecting bedding slopes.Specifically,load-displacement relationships and failure patterns were analyzed for different testing slopes with various dosages of polymer.Results show the great potential of polymer grout in improving bearing capacity,reducing settlement,and protecting slopes from being crushed under shearing.The polymer-treated slopes remained structurally intact,while the untreated slope exhibited considerable damage when subjected to loads surpassing the bearing capacity.It is also found that polymer-cemented soils concentrate around the injection pipe,forming a fan-shaped sheet-like structure.This study proves the improvement of polymer grouting for bedding slope treatment and will contribute to the development of a fast method to protect bedding slopes from landslides. 展开更多
关键词 POLYURETHANE Bedding slope GROUTING Slope protection large-scale model test
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The enlightenment of artificial intelligence large-scale model on the research of intelligent eye diagnosis in traditional Chinese medicine 被引量:1
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作者 GAO Yuan WU Zixuan +4 位作者 SHENG Boyang ZHANG Fu CHENG Yong YAN Junfeng PENG Qinghua 《Digital Chinese Medicine》 CAS CSCD 2024年第2期101-107,共7页
Eye diagnosis is a method for inspecting systemic diseases and syndromes by observing the eyes.With the development of intelligent diagnosis in traditional Chinese medicine(TCM);artificial intelligence(AI)can improve ... Eye diagnosis is a method for inspecting systemic diseases and syndromes by observing the eyes.With the development of intelligent diagnosis in traditional Chinese medicine(TCM);artificial intelligence(AI)can improve the accuracy and efficiency of eye diagnosis.However;the research on intelligent eye diagnosis still faces many challenges;including the lack of standardized and precisely labeled data;multi-modal information analysis;and artificial in-telligence models for syndrome differentiation.The widespread application of AI models in medicine provides new insights and opportunities for the research of eye diagnosis intelli-gence.This study elaborates on the three key technologies of AI models in the intelligent ap-plication of TCM eye diagnosis;and explores the implications for the research of eye diagno-sis intelligence.First;a database concerning eye diagnosis was established based on self-su-pervised learning so as to solve the issues related to the lack of standardized and precisely la-beled data.Next;the cross-modal understanding and generation of deep neural network models to address the problem of lacking multi-modal information analysis.Last;the build-ing of data-driven models for eye diagnosis to tackle the issue of the absence of syndrome dif-ferentiation models.In summary;research on intelligent eye diagnosis has great potential to be applied the surge of AI model applications. 展开更多
关键词 Traditional Chinese medicine(TCM) Eye diagnosis Artificial intelligence(AI) large-scale model Self-supervised learning Deep neural network
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Remote Control and Telemetry System for Large-scale Model Test at Sea 被引量:4
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作者 孙树政 李积德 +2 位作者 赵晓东 栾景雷 王长涛 《Journal of Marine Science and Application》 2010年第3期280-285,共6页
Physical testing of large-scale ship models at sea is a new experimental method.It is a cheap and reliable way to research the environment adaptability of a ship in complex and extreme wave conditions.It is necessary ... Physical testing of large-scale ship models at sea is a new experimental method.It is a cheap and reliable way to research the environment adaptability of a ship in complex and extreme wave conditions.It is necessary to have a stable experimental system for the test.Since the experimental area is large, a remote control system and a telemetry system are essential, and were designed by the authors.An experiment was conducted on the Songhuajiang River to test the systems.The relationship between the model's speed and its electromotor's revolutions was also measured during the model test.The results showed that the two systems make it possible to carry out large-scale model tests at sea. 展开更多
关键词 large scale model remote control telemetry systerm model test
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Design of a large-scale model for wind tunnel test of a multiadaptive flap concept 被引量:1
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作者 Mürüvvet Sinem SICIM DEMIRCI Rosario PECORA Metin Orhan KAYA 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第2期58-80,共23页
The design and application of morphing systems are ongoing issues compelling the aviation industry.The Clean Sky-program represents the most significant aeronautical research ever launched in Europe on advanced techno... The design and application of morphing systems are ongoing issues compelling the aviation industry.The Clean Sky-program represents the most significant aeronautical research ever launched in Europe on advanced technologies for greening next-generation aircraft.The primary purpose of the program is to develop new concepts aimed at decreasing the effects of aviation on the environment,increasing reliability,and promoting eco-friendly mobility.These ambitions are pursued through research on enabling technologies fostering noise and gas emissions reduction,mainly by improving aircraft aerodynamic performances.Within the Clean Sky framework,a multimodal morphing flap device was designed based on tight industrial requirements and tailored for large civil aircraft applications.The flap is deployed in one unique setting,and its cross section is morphed differently in take-off and landing to get the necessary extra lift for the specific flight phase.Moreover,during the cruise,the tip of the flap is deflected for load control and induced drag reduction.Before manufacturing the first flap prototype,a high-speed(Ma=0.3),large-scale test campaign(geometric scale factor 1:3)was deemed necessary to validate the performance improvements brought by this novel system at the aircraft level.On the other hand,the geometrical scaling of the flap prototype was considered impracticable due to the unscalability of the embedded mechanisms and actuators for shape transition.Therefore,a new architecture was conceived for the flap model to comply with the scaled dimensions requirements,withstand the relevant loads expected during the wind tunnel tests and emulate the shape transition capabilities of the true-scale flap.Simplified strategies were developed to effectively morph the model during wind tunnel tests while ensuring the robustness of each morphed configuration and maintaining adequate stiffness levels to prevent undesirable deviations from the intended aerodynamic shapes.Additionally,a simplified design was conceived for the flap-wing interface,allowing for quick adjustments of the flap setting and enabling load transmission paths like those arising between the full-scale flap and the wing.The design process followed for the definition of this challenging wind tunnel model has been addressed in this work,covering the definition of the conceptual layout,the numerical evaluation of the most severe loads expected during the test,and the verification of the structural layout by means of advanced finite element analyses. 展开更多
关键词 Morphing structures Smart aircraft Morphing flap Adaptive systems Finger-like ribs Wind tunnel tests large-scale morphing archi-tectures Variable camber airfoil
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Influence of differential settlement on pavement structure of widened roads based on large-scale model test 被引量:14
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作者 Xiaolin Weng Wei Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE 2011年第1期90-96,共7页
This study introduced at first the background of numerous highway widening projects that have been developed in recent years in China.Using a large ground settlement simulator and a fiber Bragg grating(FBG)strain sens... This study introduced at first the background of numerous highway widening projects that have been developed in recent years in China.Using a large ground settlement simulator and a fiber Bragg grating(FBG)strain sensor network system,a large-scale model test,with a similarity ratio of 1:2,was performed to analyze the influence of differential settlement between new and old subgrades on pavement structure under loading condition.The result shows that excessive differential settlement can cause considerable tensile strain in the pavement structure of a widened road,for which a maximum value(S)of 6 cm is recommended.Under the repetitive load,the top layers of pavement structure are subjected to the alternate action of tensile and compressive strains,which would eventually lead to a fatigue failure of the pavement.However,application of geogrid to the splice between the new and the old roads can reduce differential settlement to a limited extent.The new subgrade of a widened road is vulnerable to the influence of dynamic load transferred from the above pavement structures.While for the old subgrade,due to its comparatively high stiffness,it can well spread the load on the pavement statically or dynamically.The test also shows that application of geogrid can effectively prevent or defer the failure of pavement structure.With geogrid,the modulus of resilience of the subgrade is increased and inhomogeneous deformation can be reduced;therefore,the stress/strain distribution in pavement structure under loading condition becomes uniform.The results obtained in this context are expected to provide a helpful reference for structural design and maintenance strategy for future highway widening projects. 展开更多
关键词 widened subgrade differential settlement fiber Bragg grating(FBG)strain sensor model test
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Recent Progresses in Synthesis of Cyclic Polymers in Large-scale and Some Functionalized Composites
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作者 QU Kairu GUO Lyuzhou +3 位作者 WANG Wenbin YAN Xuzhou CAO Xuezheng YANG Zhenzhong 《高等学校化学学报》 北大核心 2026年第1期42-57,共16页
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam... Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering. 展开更多
关键词 Cyclic polymer large-scale synthesis Single-chain nanoparticle Performance Composite
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Four-dimensional integrated standardization practice in the construction of large-scale complex information systems
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作者 Zhang Qi Chen Shuang Ni Xibing 《China Standardization》 2026年第2期62-66,共5页
Large-scale complex systems are integral to the functioning of various organizations within the national economy.Despite their significance,the lengthy construction cycles and the involvement of multiple entities ofte... Large-scale complex systems are integral to the functioning of various organizations within the national economy.Despite their significance,the lengthy construction cycles and the involvement of multiple entities often result in the deprioritization of standardized management practices,as they do not yield immediate benefits.The implementation of such systems typically encompasses the integrated phases of "development,construction,utiliz ation,and operation and maintenance".To enhance the overall delivery quality of these systems,it is imperative to dismantle the management barriers among these phases and adopt a holistic approach to standardized management.This paper takes a specific system project as a research object to identify common challenges,and proposes improvement strategies in the implementation of standar dized management.Empirical results indicate a substantial reduction in the system s full-lifecycle costs. 展开更多
关键词 large-scale complex information systems quality management STANDARDIZATION
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Two Unconventional Types of Large-scale Circulation Anomalies Inducing Heavy Rainfall over the Yangtze River Basin
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作者 Xinyu LI Mengyao CHEN Riyu LU 《Advances in Atmospheric Sciences》 2026年第3期565-577,共13页
Summer rainfall in the Yangtze River basin(YRB)is favored by two key factors in the lower troposphere:the tropical anticyclonic anomaly over the western North Pacific and the extratropical northeasterly anomalies to t... Summer rainfall in the Yangtze River basin(YRB)is favored by two key factors in the lower troposphere:the tropical anticyclonic anomaly over the western North Pacific and the extratropical northeasterly anomalies to the north of the YRB.This study,however,found that approximately 46%of heavy rainfall events in the YRB occur when only one factor appears and the other is opposite signed.Accordingly,these heavy rainfall events can be categorized into two types:the extratropical northeasterly anomalies but tropical cyclonic anomaly(first unconventional type),and the tropical anticyclonic anomaly but extratropical southwesterly anomalies(second unconventional type).Anomalous water vapor convergence and upward motion exists for both types,but through different mechanisms.For the first type,the moisture convergence and upward motion are induced by a cyclonic anomaly over the YRB,which appears in the mid and lower troposphere and originates from the upstream region.For the second type,a mid-tropospheric cyclonic anomaly over Lake Baikal extends southward and results in southwesterly anomalies over the YRB,in conjunction with the tropical anticyclonic anomaly.The southwesterly anomalies transport water vapor to the YRB and lead to upward motion through warm advection.This study emphasizes the role of mid-tropospheric circulations in inducing heavy rainfall in the YRB. 展开更多
关键词 Yangtze River basin heavy rainfall large-scale circulation anomalies
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Adaptive event-triggered decentralized control for nonlinear interconnected large-scale systems with actuator failures:a fully actuated system approach
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作者 Yueyao Ye Yanan Qi +2 位作者 Yiyu Feng Xiaofeng Xu Xianfu Zhang 《Control Theory and Technology》 2026年第1期82-95,共14页
This study develops an event-triggered control strategy utilizing the fully actuated system approach for nonlinear interconnected large-scale systems containing actuator failures.First,to reduce the complexity of the ... This study develops an event-triggered control strategy utilizing the fully actuated system approach for nonlinear interconnected large-scale systems containing actuator failures.First,to reduce the complexity of the design process,we transform the studied system into the form of a fully actuated system through a state transformation.Then,to address the unknown nonlinear functions and actuator fault parameters,we employ neural networks and adaptive estimation techniques,respectively.Moreover,to reduce the control cost and improve the control efficiency,we introduce event-triggered inputs into the control strategy.It is proved by the Lyapunov stability analysis that all signals of the closed-loop system are bounded and the output of system eventually converge to a bounded region.The efficacy of the control approach is ultimately demonstrated via the simulation of an actual machine feeding system. 展开更多
关键词 Nonlinear interconnected large-scale systems Fully actuated system approach Actuator failures Neural networks
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Evolution and triggering mechanism of fault-slip rockbursts in deep tunnels:Insights from 3D printed large-scale physical models
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作者 Shi-Ming Mei Xia-Ting Feng +3 位作者 Zheng-Wei Li Ben-Guo He Cheng-Xiang Yang Wei Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期6821-6836,共16页
The excavation of deep tunnels crossing faults is highly prone to triggering rockburst disasters,which has become a significant engineering issue.In this study,taking the fault-slip rockbursts from a deep tunnel in so... The excavation of deep tunnels crossing faults is highly prone to triggering rockburst disasters,which has become a significant engineering issue.In this study,taking the fault-slip rockbursts from a deep tunnel in southwestern China as the engineering prototype,large-scale three-dimensional(3D)physical model tests were conducted on a 3D-printed complex geological model containing two faults.Based on the selfdeveloped 3D loading system and excavation device,the macroscopic failure of fault-slip rockbursts was simulated indoors.The stress,strain,and fracturing characteristics of the surrounding rock near the two faults were systematically evaluated during excavation and multistage loading.The test results effectively revealed the evolution and triggering mechanism of fault-slip rockbursts.After the excavation of a highstress tunnel,stress readjustment occurred.Owing to the presence of these two faults,stress continued to accumulate in the rock mass between them,leading to the accumulation of fractures.When the shear stress on a fault surface exceeded its shear strength,sudden fault slip and dislocation occurred,thus triggering rockbursts.Rockbursts occurred twice in the vault between the two faults,showing obvious intermittent characteristics.The rockburst pit was controlled by two faults.When the faults remained stable,tensile failure predominated in the surrounding rock.However,when the fault slip was triggered,shear failure in the surrounding rock increased.These findings provide valuable insights for enhancing the comprehension of fault-slip rockbursts. 展开更多
关键词 Fault-slip rockbursts Evolution mechanism 3D printing large-scale physical model test Deep tunnel
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Engine Failure Prediction on Large-Scale CMAPSS Data Using Hybrid Feature Selection and Imbalance-Aware Learning
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作者 Ahmad Junaid Abid Iqbal +3 位作者 Abuzar Khan Ghassan Husnain Abdul-Rahim Ahmad Mohammed Al-Naeem 《Computers, Materials & Continua》 2026年第4期1485-1508,共24页
Most predictive maintenance studies have emphasized accuracy but provide very little focus on Interpretability or deployment readiness.This study improves on prior methods by developing a small yet robust system that ... Most predictive maintenance studies have emphasized accuracy but provide very little focus on Interpretability or deployment readiness.This study improves on prior methods by developing a small yet robust system that can predict when turbofan engines will fail.It uses the NASA CMAPSS dataset,which has over 200,000 engine cycles from260 engines.The process begins with systematic preprocessing,which includes imputation,outlier removal,scaling,and labelling of the remaining useful life.Dimensionality is reduced using a hybrid selection method that combines variance filtering,recursive elimination,and gradient-boosted importance scores,yielding a stable set of 10 informative sensors.To mitigate class imbalance,minority cases are oversampled,and class-weighted losses are applied during training.Benchmarking is carried out with logistic regression,gradient boosting,and a recurrent design that integrates gated recurrent units with long short-term memory networks.The Long Short-Term Memory–Gated Recurrent Unit(LSTM–GRU)hybrid achieved the strongest performance with an F1 score of 0.92,precision of 0.93,recall of 0.91,ReceiverOperating Characteristic–AreaUnder the Curve(ROC-AUC)of 0.97,andminority recall of 0.75.Interpretability testing using permutation importance and Shapley values indicates that sensors 13,15,and 11 are the most important indicators of engine wear.The proposed system combines imbalance handling,feature reduction,and Interpretability into a practical design suitable for real industrial settings. 展开更多
关键词 Predictive maintenance CMAPSS dataset feature selection class imbalance LSTM-GRUhybrid model INTERPRETABILITY industrial deployment
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Applicable Regions of Spherical and Plane Wave Models for Extremely Large-Scale Array Communications
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作者 Li Renwang Sun Shu Tao Meixia 《China Communications》 2025年第5期128-151,共24页
Extremely large-scale array(XL-array)communications can significantly improve the transmission rate,spectral efficiency,and spatial resolution,and has great potential in next-generation mobile communication networks.A... Extremely large-scale array(XL-array)communications can significantly improve the transmission rate,spectral efficiency,and spatial resolution,and has great potential in next-generation mobile communication networks.A crucial problem in XLarray communications is to determine the boundary of applicable regions of the plane wave model(PWM)and spherical wave model(SWM).In this paper,we propose new PWM/SWM demarcations for XL-arrays from the viewpoint of channel gain and rank.Four sets of results are derived for four different array setups.First,an equi-power line is derived for a point-touniform linear array(ULA)scenario,where an inflection point is found at±π6 central incident angles.Second,an equi-power surface is derived for a point-touniform planar array(UPA)scenario,and it is proved that cos2(ϕ)cos2(φ)=12 is a dividing curve,where ϕ andφdenote the elevation and azimuth angles,respectively.Third,an accurate and explicit expression of the equi-rank surface is obtained for a ULA-to-ULA scenario.Finally,an approximated expression of the equirank surface is obtained for a ULA-to-UPA scenario.With the obtained closed-form expressions,the equirank surface for any antenna structure and any angle can be well estimated.Furthermore,the effect of scatterers is also investigated,from which some insights are drawn. 展开更多
关键词 effective rank extremely large-scale array(XL-array) near-/far-field Rayleigh distance spherical/plane wave
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Integrating geographic information system and 3D virtual reality for optimized modeling of large-scale photovoltaic wind hybrid system:A case study in Dakhla City,Morocco 被引量:1
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作者 Elmostafa Achbab Rachid Lambarki +1 位作者 Hassan Rhinane Dennoun Saifaoui 《Energy Geoscience》 2025年第2期174-193,共20页
This research pioneers the integration of geographic information systems(GIS)and 3D modeling within a virtual reality(VR)framework to assess the viability and planning of a 20 MW hybrid wind-solarphotovoltaic(PV)syste... This research pioneers the integration of geographic information systems(GIS)and 3D modeling within a virtual reality(VR)framework to assess the viability and planning of a 20 MW hybrid wind-solarphotovoltaic(PV)system connected to the local grid.The study focuses on Dakhla,Morocco,a region with vast untapped renewable energy potential.By leveraging GIS,we are innovatively analyzing geographical and environmental factors that influence optimal site selection and system design.The incorporation of VR technologies offers an unprecedented level of realism and immersion,allowing stakeholders to virtually experience the project's impact and design in a dynamic,interactive environment.This novel methodology includes extensive data collection,advanced modeling,and simulations,ensuring that the hybrid system is precisely tailored to the unique climatic and environmental conditions of Dakhla.Our analysis reveals that the region possesses a photovoltaic solar potential of approximately2400 k Wh/m^(2) per year,with an average annual wind power density of about 434 W/m^(2) at an 80-meter hub height.Productivity simulations indicate that the 20 MW hybrid system could generate approximately 60 GWh of energy per year and 1369 GWh over its 25-year lifespan.To validate these findings,we employed the System Advisor Model(SAM)software and the Global Solar Photovoltaic Atlas platform.This comprehensive and interdisciplinary approach not only provides a robust assessment of the system's feasibility but also offers valuable insights into its potential socio-economic and environmental impact. 展开更多
关键词 Geographic information systems 3D virtual reality(VR)modeling Wind energy Solar photovoltaic(PV)energy Hybrid renewable energy system assessment
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A Survey of Large-Scale Deep Learning Models in Medicine and Healthcare
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作者 Zhiwei Chen Runze Liu +2 位作者 Shitao Huang Yangyang Guo Yongjun Ren 《Computer Modeling in Engineering & Sciences》 2025年第7期37-81,共45页
The rapid advancement of artificial intelligence technology is driving transformative changes in medical diagnosis,treatment,and management systems through large-scale deep learning models-a process that brings both g... The rapid advancement of artificial intelligence technology is driving transformative changes in medical diagnosis,treatment,and management systems through large-scale deep learning models-a process that brings both groundbreaking opportunities and multifaceted challenges.This study focuses on the medical and healthcare applications of large-scale deep learning architectures,conducting a comprehensive survey to categorize and analyze their diverse uses.The survey results reveal that current applications of large models in healthcare encompass medical data management,healthcare services,medical devices,and preventive medicine,among others.Concurrently,large models demonstrate significant advantages in the medical domain,especially in high-precision diagnosis and prediction,data analysis and knowledge discovery,and enhancing operational efficiency.Nevertheless,we identify several challenges that need urgent attention,including improving the interpretability of large models,strengthening privacy protection,and addressing issues related to handling incomplete data.This research is dedicated to systematically elucidating the deep collaborative mechanisms between artificial intelligence and the healthcare field,providing theoretical references and practical guidance for both academia and industry. 展开更多
关键词 Large models healthcare artificial intelligence data management medical applications
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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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A model LayerDFN for characterizing the inherent anisotropic rocks with large-scale and dense joints
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作者 Gang Han Shuling Huang +4 位作者 Chuanqing Zhang Xiuli Ding Yuting Zhang Yang Gao Jun He 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1569-1584,共16页
Large-scale and heavily jointed rocks have inherent planes of anisotropy and secondary structural planes,such as dominant joint sets and random fractures,which result in significant differences in their failure mechan... Large-scale and heavily jointed rocks have inherent planes of anisotropy and secondary structural planes,such as dominant joint sets and random fractures,which result in significant differences in their failure mechanism and deformation behavior compared to other rock types.To address this issue,inherent anisotropic rocks with large-scale and dense joints are considered to be composed of the rock matrix,inherent planes of anisotropy,and secondary structural planes.Then a new implicit continuum model called LayerDFN is developed based on the crack tensor and damage tensor theories to characterize the mechanical properties of inherent anisotropic rocks.Furthermore,the LayerDFN model is implemented in the FLAC3D software,and a series of numerical results for typical example problems is compared with those obtained from the 3DEC,the analytical solutions,similar classical models,laboratory uniaxial compression tests,and field rigid bearing plate tests.The results demonstrate that the LayerDFN model can effectively capture the anisotropic mechanical properties of inherent anisotropic rocks,and can quantitatively characterize the damaging effect of the secondary structural planes.Overall,the numerical method based on the LayerDFN model provides a comprehensive and reliable approach for describing and analyzing the behavior of inherent anisotropic rocks,which will provide valuable insights for engineering design and decision-making processes. 展开更多
关键词 Inherent anisotropic rocks Secondary structural planes Constitutive model Crack tensor Damage tensor
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Large-scale complex physical modeling and precisionanalysis 被引量:6
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作者 吴满生 狄帮让 +4 位作者 魏建新 梁向豪 周翼 刘依谋 孔昭举 《Applied Geophysics》 SCIE CSCD 2014年第2期245-251,255,共8页
Large-scale 3D physical models of complex structures can be used to simulate hydrocarbon exploration areas. The high-fidelity simulation of actual structures poses challenges to model building and quality control. Suc... Large-scale 3D physical models of complex structures can be used to simulate hydrocarbon exploration areas. The high-fidelity simulation of actual structures poses challenges to model building and quality control. Such models can be used to collect wideazimuth, multi-azimuth, and full-azimuth seismic data that can be used to verify various 3D processing and interpretation methods. Faced with nonideal imaging problems owing to the extensive complex surface conditions and subsurface structures in the oil-rich foreland basins of western China, we designed and built the KS physical model based on the complex subsurface structure. This is the largest and most complex 3D physical model built to date. The physical modeling technology advancements mainly involve 1) the model design method, 2) the model casting flow, and 3) data acquisition. A 3D velocity model of the physical model was obtained for the first time, and the model building precision was quantitatively analyzed. The absolute error was less than 3 mm, which satisfies the experimental requirements. The 3D velocity model obtained from 3D measurements of the model layers is the basis for testing various imaging methods. Furthermore, the model is considered a standard in seismic physical modeling technology. 展开更多
关键词 complex structure seismic physical modeling modeling construction ACQUISITION
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Large-scale model test study on the water pressure resistance of construction joints of karst tunnel linings 被引量:1
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作者 Meng HUANG Mingli HUANG +2 位作者 Ze YANG Yuan SONG Zhien ZHANG 《Frontiers of Structural and Civil Engineering》 SCIE EI CSCD 2023年第8期1249-1263,共15页
Model tests and numerical calculations were adopted based on the New Yuanliangshan tunnel project to investigate the water pressure resistance of lining construction joints in high-pressure and water-rich karst tunnel... Model tests and numerical calculations were adopted based on the New Yuanliangshan tunnel project to investigate the water pressure resistance of lining construction joints in high-pressure and water-rich karst tunnels.A large-scale model test was designed and conducted,innovatively transforming the external water pressure of the lining construction joint into internal water pressure.The effects of the embedded position and waterstop type on the water pressure resistance of the construction joint were analyzed,and the reliability of the model test was verified via numerical calculations.The results show that using waterstops can significantly improve the water pressure resistance of lining construction joints.The water pressure resistance of the lining construction joint is positively correlated with the lining thickness and embedded depth of the waterstop.In addition,the type of waterstop significantly influences the water pressure resistance of lining construction joints.The test results show that the water pressure resistance of the embedded transverse reinforced waterstop is similar to that of the steel plate waterstop,and both have more advantages than the rubber waterstop.The water pressure resistance of the construction joint determined via numerical calculations is similar to the model test results,indicating that the model test results have high accuracy and reliability.This study provides a reference for similar projects and has wide applications. 展开更多
关键词 karst tunnel lining construction joint water pressure resistance large-scale model test numerical calculations
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Large-Scale Model Meets Federated Learning:A Hierarchical Hybrid Distributed Training Mechanism for Intelligent Intersection Large-Scale Model
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作者 Chang Liu Shaoyong Guo +2 位作者 Fangfang Dang Xuesong Qiu Sujie Shao 《Big Data Mining and Analytics》 CSCD 2024年第4期1031-1049,共19页
The large-scale model(LSM)can handle large-scale data and complex problems,effectively improving the intelligence level of urban intersections.However,the traffic conditions at intersections are becoming increasingly ... The large-scale model(LSM)can handle large-scale data and complex problems,effectively improving the intelligence level of urban intersections.However,the traffic conditions at intersections are becoming increasingly complex,so the intelligent intersection LSMs(I2LSMs)also need to be continuously learned and updated.The traditional cloud-based training method incurs a significant amount of computational and storage overhead,and there is a risk of data leakage.The combination of edge artificial intelligence and federated learning provides an efficient and highly privacy protected computing mode.Therefore,we propose a hierarchical hybrid distributed training mechanism for I2LSM.Firstly,relying on the intelligent intersection system for cloud-network-terminal integration,we constructed an I2LSM hierarchical hybrid distributed training architecture.Then,we propose a hierarchical hybrid federated learning(H2Fed)algorithm that combines the advantages of centralized federated learning and decentralized federated learning.Further,we propose an adaptive compressed sensing algorithm to reduce the communication overhead.Finally,we analyze the convergence of the H2Fed algorithm.Experimental results show that the H2Fed algorithm reduces the communication overhead by 21.6%while ensuring the accuracy of the model. 展开更多
关键词 intelligent intersections large-scale models edge artificial intelligence(AI) federated learning compressed sensing
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Validating the Runoff from the PRECIS Model Using a Large-Scale Routing Model 被引量:3
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作者 曹丽娟 董文杰 +2 位作者 许吟隆 张勇 Michael SPARROW 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第5期855-862,共8页
The streamflow over the Yellow River basin is simulated using the PRECIS (Providing REgional Climates for Impacts Studies) regional climate model driven by 15-year (1979-1993) ECMWF reanalysis data as the initial ... The streamflow over the Yellow River basin is simulated using the PRECIS (Providing REgional Climates for Impacts Studies) regional climate model driven by 15-year (1979-1993) ECMWF reanalysis data as the initial and lateral boundary conditions and an off-line large-scale routing model (LRM). The LRM uses physical catchment and river channel information and allows streamflow to be predicted for large continental rivers with a 1°×1° spatial resolution. The results show that the PRECIS model can reproduce the general southeast to northwest gradient distribution of the precipitation over the Yellow River basin, The PRECIS- LRM model combination has the capability to simulate the seasonal and annual streamflow over the Yellow River basin. The simulated streamflow is generally coincident with the naturalized streamflow both in timing and in magnitude. 展开更多
关键词 regional climate model large-scale routing model model validation RUNOFF the Yellow River
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