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Delaminated lower slab thermal regime before slab break-off in the Pamirs:Implications from 3D kinematic modeling
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作者 Haris Faheem YingFeng Ji +6 位作者 Waqar Ahmed Rui Qu Ye Zhu Fitriani Fitriani Jun Yang Shoichi Yoshioka Nobuaki Suenaga 《Earth and Planetary Physics》 2026年第1期13-21,共9页
The intracontinental subduction of a>200-km-long section of the Tajik-Tarim lithosphere beneath the Pamir Mountains is proposed to explain nearly 30 km of shortening in the Tajik fold-thrust belt and the Pamir upli... The intracontinental subduction of a>200-km-long section of the Tajik-Tarim lithosphere beneath the Pamir Mountains is proposed to explain nearly 30 km of shortening in the Tajik fold-thrust belt and the Pamir uplift.Seismic imaging revealed that the upper slab was scraped and that the lower slab had subducted to a depth of>150 km.These features constitute the tectonic complexity of the Pamirs,as well as the thermal subduction mechanism involved,which remains poorly understood.Hence,in this study,high-resolution three-dimensional(3D)kinematic modeling is applied to investigate the thermal structure and geometry of the subducting slab beneath the Pamirs.The modeled slab configuration reveals distinct along-strike variations,with a steeply dipping slab beneath the southern Pamirs,a more gently inclined slab beneath the northern Pamirs,and apparent upper slab termination at shallow depths beneath the Pamirs.The thermal field reveals a cold slab core after delamination,with temperatures ranging from 400℃to 800℃,enveloped by a hotter mantle reaching~1400℃.The occurrence of intermediate-depth earthquakes aligns primarily with colder slab regions,particularly near the slab tear-off below the southwestern Pamirs,indicating a strong correlation between slab temperature and seismicity.In contrast,the northern Pamirs exhibit reduced seismicity at depth,which is likely associated with thermal weakening and delamination.The central Pamirs show a significant thermal anomaly caused by a concave slab,where the coldest crust does not descend deeply,further suggesting crustal detachment or mechanical failure.The lateral asymmetry in slab temperature possibly explains the mechanism of lateral tearing and differential slab-mantle coupling. 展开更多
关键词 PAMIRS SUBDUCTION 3D kinematic modeling slab geometry intermediate-depth earthquake crustal delamination seismicity distribution
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Automatic gating and riser system design and defect control for K4169 superalloy guide blade casting based on parametric 3D modeling-simulation integrated system
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作者 Le-chuan Li Ya-jun Yin +4 位作者 Bing-zheng Fan Guo-yan Shui Xiao-yuan Ji Jian-xin Zhou Lei Jin 《China Foundry》 2026年第1期20-30,共11页
Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical si... Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical simulation plays a significant role in quantitatively evaluating current processes and making targeted improvements,but its limitations lie in the inability to dynamically reflect the formation outcomes of castings under varying process conditions,making real-time adjustments to gating and riser designs challenging.In this study,an automated design model for gating and riser systems based on integrated parametric 3D modeling-simulation framework is proposed,which enhances the flexibility and usability of evaluating the casting process by simulation.Firstly,geometric feature extraction technology is employed to obtain the geometric information of the target casting.Based on this information,an automated design framework for gating and riser systems is established,incorporating multiple structural parameters for real-time process control.Subsequently,the simulation results for various structural parameters are analyzed,and the influence of these parameters on casting formation is thoroughly investigated.Finally,the optimal design scheme is generated and validated through experimental verification.Simulation analysis and experimental results show that using a larger gate neck(24 mm in side length) and external risers promotes a more uniform temperature distribution and a more stable flow state,effectively eliminating shrinkage cavities and enhancing process yield by 15%. 展开更多
关键词 numerical simulation automatic design investment casting parametric 3D modeling gating and riser system
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Solubility and Thermodynamic Modeling of 3⁃Nitro⁃1,2,4⁃triazole⁃5⁃one(NTO)in Different Binary Solvents 被引量:1
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作者 GUO Hao-qi YANG Yu-lin 《含能材料》 北大核心 2025年第3期295-303,共9页
Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging f... Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging from 278.15 K to 318.15 K.The solubility in each system was found to be positively correlated with temperature.Furthermore,solubility data were analyzed using four equations:the modified Apelblat equation,Van’t Hoff equation,λh equation and CNIBS/R-K equations,and they provided satisfactory results for both two systems.The average root-mean-square deviation(105RMSD)values for these models were less than 13.93.Calculations utilizing the Van’t Hoff equation and Gibbs equations facilitated the derivation of apparent thermodynamic properties of NTO dissolution in the two systems,including values for Gibbs free energy,enthalpy and entropy.The%ζ_(H)is larger than%ζ_(TS),and all the%ζ_(H)data are≥58.63%,indicating that the enthalpy make a greater contribution than entropy to theΔG_(soln)^(Θ). 展开更多
关键词 3-nitro-l 2 4-triazole-5-one(NTO) SOLUBILITY thermodynamic models apparent thermodynamic analysis
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Development of Patient-Derived Conditionally Reprogrammed 3D Breast Cancer Culture Models for Drug Sensitivity Evaluation
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作者 Jing Cai Haoyun Zhu +4 位作者 Weiling Guo Ting Huang Pangzhou Chen Wen Zhou Ziyun Guan 《Oncology Research》 2026年第1期500-520,共21页
Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual pat... Background:Therapeutic responses of breast cancer vary among patients and lead to drug resistance and recurrence due to the heterogeneity.Current preclinical models,however,are inadequate for predicting individual patient responses towards different drugs.This study aimed to investigate the patient-derived breast cancer culture models for drug sensitivity evaluations.Methods:Tumor and adjacent tissues from female breast cancer patients were collected during surgery.Patient-derived breast cancer cells were cultured using the conditional reprogramming technique to establish 2D models.The obtained patient-derived conditional reprogramming breast cancer(CRBC)cells were subsequently embedded in alginate-gelatin methacryloyl hydrogel microspheres to form 3D culture models.Comparisons between 2D and 3D models were made using immunohistochemistry(tumor markers),MTS assays(cell viability),flow cytometry(apoptosis),transwell assays(migration),and Western blotting(protein expression).Drug sensitivity tests were conducted to evaluate patient-specific responses to anti-cancer agents.Results:2D and 3D culture models were successfully established using samples from eight patients.The 3D models retained histological and marker characteristics of the original tumors.Compared to 2D cultures,3D models exhibited increased apoptosis,enhanced drug resistance,elevated stem cell marker expression,and greater migration ability—features more reflective of in vivo tumor behavior.Conclusion:Patient-derived 3D CRBC models effectively mimic the in vivo tumor microenvironment and demonstrate stronger resistance to anti-cancer drugs than 2D models.These hydrogel-based models offer a cost-effective and clinically relevant platform for drug screening and personalized breast cancer treatment. 展开更多
关键词 Patient-derived breast cancer cells conditional reprogramming hydrogel microsphere 3D culture model drug screening
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DNASE1L3 Mediates Hepatocellular Carcinoma Tumor Growth and Organoid Models via the Wnt/β-Catenin Signaling Pathway
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作者 Shulong Zhang Yijun Zhao +5 位作者 Li Geng Feihong Song Li Feng Jun Jiang Qianqian Cai Fei Fan 《Oncology Research》 2026年第3期691-724,共34页
Background:Hepatocellular carcinoma(HCC)is a highly lethal malignancy driven by both intrinsic oncogenic pathways and immune microenvironmental regulation.Emerging evidence suggests that DNASE1L3 may influence tumor b... Background:Hepatocellular carcinoma(HCC)is a highly lethal malignancy driven by both intrinsic oncogenic pathways and immune microenvironmental regulation.Emerging evidence suggests that DNASE1L3 may influence tumor biology and immune responses;however,its specific roles in HCC progression and macrophage-mediated regulation remain unclear.This study aimed to elucidate the biological functions of DNASE1L3 in HCC and to determine how it modulates tumor behavior and immune interactions.Methods:Bioinformatics analyses of the GSE41804 and Cancer Genome Atlas-Liver Hepatocellular Carcinoma(TCGA-LIHC)datasets were used to identify hub genes.Functional assays assessed the impact of DNASE1L3 on HCC cell proliferation,migration,invasion,and cell cycle progression.The effects of DNASE1L3 on macrophage polarization and the Wnt/β-catenin signaling pathway were examined using a co-culture system.An HCC organoid model was established to further validate its regulatory function.Results:Eight prognostic signature genes were identified,with deoxyribonuclease I-like 3(DNase I-like 3)selected as the hub gene.DNASE1L3 overexpression suppressed HCC cell growth,inhibited migration and invasion,induced G1 arrest,and modulated epithelial-mesenchymal transition(EMT)markers.DNASE1L3 knockdown promoted M2-like macrophage polarization.Mechanistically,DNASE1L3 interacted withβ-catenin to enhance its ubiquitination and degradation,thereby inhibiting Wnt/β-catenin signaling and reducing PD-L1 expression.DNASE1L3 overexpression similarly restricted organoid growth and suppressed pathway activity.Conclusion:DNASE1L3 acts as a negative regulator of HCC progression by targeting the Wnt/β-catenin pathway and reducing PD-L1 expression,thereby influencing both tumor cell behavior and macrophage-mediated immune responses. 展开更多
关键词 Hepatocellular carcinoma DNASE1L3 Wnt/β-catenin signaling pathway organoid models tumor growth
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Automatic identification of discontinuities and refined modeling of rock blocks from 3D point cloud data of rock surfaces 被引量:1
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作者 Yaopeng Ji Shengyuan Song +5 位作者 Jianping Chen Jingyu Xue Jianhua Yan Yansong Zhang Di Sun Qing Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期3093-3106,共14页
The spatial distribution of discontinuities and the size of rock blocks are the key indicators for rock mass quality evaluation and rockfall risk assessment.Traditional manual measurement is often dangerous or unreach... The spatial distribution of discontinuities and the size of rock blocks are the key indicators for rock mass quality evaluation and rockfall risk assessment.Traditional manual measurement is often dangerous or unreachable at some high-steep rock slopes.In contrast,unmanned aerial vehicle(UAV)photogrammetry is not limited by terrain conditions,and can efficiently collect high-precision three-dimensional(3D)point clouds of rock masses through all-round and multiangle photography for rock mass characterization.In this paper,a new method based on a 3D point cloud is proposed for discontinuity identification and refined rock block modeling.The method is based on four steps:(1)Establish a point cloud spatial topology,and calculate the point cloud normal vector and average point spacing based on several machine learning algorithms;(2)Extract discontinuities using the density-based spatial clustering of applications with noise(DBSCAN)algorithm and fit the discontinuity plane by combining principal component analysis(PCA)with the natural breaks(NB)method;(3)Propose a method of inserting points in the line segment to generate an embedded discontinuity point cloud;and(4)Adopt a Poisson reconstruction method for refined rock block modeling.The proposed method was applied to an outcrop of an ultrahigh steep rock slope and compared with the results of previous studies and manual surveys.The results show that the method can eliminate the influence of discontinuity undulations on the orientation measurement and describe the local concave-convex characteristics on the modeling of rock blocks.The calculation results are accurate and reliable,which can meet the practical requirements of engineering. 展开更多
关键词 Three-dimensional(3D)point cloud Rock mass Automatic identification Refined modeling Unmanned aerial vehicle(UAV)
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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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Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures
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作者 Muhammad Qasim Khan Fazal Malik +1 位作者 Fahad Alturise Noor Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期123-153,共31页
Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important a... Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important and scarce network resources such as bandwidth and processing power.There have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial losses.This paper draws its motivation from such real network disaster incidents attributed to signaling storms.In this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and countermeasures.We provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding solutions.Another important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a table.This paper presents an update and an extension of our earlier conference publication.To our knowledge,no similar survey study exists on the subject. 展开更多
关键词 Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication
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3D Computational Modeling and Stability Analysis of Highway Slope:A Case Study from the X104 Section in Ganxian County
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作者 Fujie Dai Yiwen Jin +1 位作者 Yongliang Wang Jiajun Li 《Journal of Electronic Research and Application》 2025年第2期65-68,共4页
Highway planning requires geological surveys and stability analysis of the surrounding area.In the early stage of the survey,the modeling and stability analysis of the survey area can be carried out by using GIS softw... Highway planning requires geological surveys and stability analysis of the surrounding area.In the early stage of the survey,the modeling and stability analysis of the survey area can be carried out by using GIS software to intuitively understand the topography of the study area.The use of DEM to extract terrain factors can be used for simple stability analysis and the source data is easy to obtain,simple to operate,fast to analyze,and reliable analysis results.In this paper,taking the X104 road section in Ganxian County as an example,the ArcGIS platform is used to carry out 3D modeling visualization and stability analysis,and the stability evaluation map of the study area is obtained. 展开更多
关键词 3D modeling STABILITY GIS Highway planning
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Research and experimental validation for 3GPP ISAC channel modeling standardization
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作者 Yuxiang Zhang Jianhua Zhang +5 位作者 Jiwei Zhang Yuanpeng Pei Yameng Liu Lei Tian Tao Jiang Guangyi Liu 《Digital Communications and Networks》 2025年第5期1601-1613,共13页
Integrated Sensing and Communication(ISAC)is considered a key technology in 6G networks.An accurate sensing channel model is crucial for the design and sensing performance evaluation of ISAC systems.The widely used Ge... Integrated Sensing and Communication(ISAC)is considered a key technology in 6G networks.An accurate sensing channel model is crucial for the design and sensing performance evaluation of ISAC systems.The widely used Geometry-Based Stochastic Model(GBSM),typically applied in standardized channel modeling,mainly focuses on the statistical fading characteristics of the channel.However,it fails to capture the characteristics of targets in ISAC systems,such as their positions and velocities,as well as the impact of the targets on the background.To address this issue,this paper proposes an Extended-GBSM(E-GBSM)sensing channel model that incorporates newly discovered channel characteristics into a unified modeling framework.In this framework,the sensing channel is divided into target and background channels.For the target channel,the model introduces a concatenated modeling approach,while for the background channel,a parameter called the power control factor is introduced to assess impact of the target on the background channel,making the modeling framework applicable to both mono-static and bi-static sensing modes.To validate the proposed model’s effectiveness,measurements of target and background channels are conducted across a wide range of indoor and outdoor scenarios,covering various sensing targets such as metal plates,reconfigurable intelligent surfaces,human bodies,unmanned aerial vehicles,and vehicles.The experimental results provide important theoretical support and empirical data for the standardization of ISAC channel modeling. 展开更多
关键词 ISAC Channel modeling 3GPP standardization Channel measurement
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Vector Extraction from Design Drawings for Intelligent 3D Modeling of Transmission Towers
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作者 Ziqiang Tang Chao Han +5 位作者 Hongwu Li Zhou Fan Ke Sun Yuntian Huang Yuhang Chen Chenxing Wang 《Computers, Materials & Continua》 2025年第2期2813-2829,共17页
Accurate vector extraction from design drawings is required first to automatically create 3D models from pixel-level engineering design drawings. However, this task faces the challenges of complicated design shapes as... Accurate vector extraction from design drawings is required first to automatically create 3D models from pixel-level engineering design drawings. However, this task faces the challenges of complicated design shapes as well as cumbersome and cluttered annotations on drawings, which interfere with the vector extraction heavily. In this article, the transmission tower containing the most complex structure is taken as the research object, and a semantic segmentation network is constructed to first segment the shape masks from the pixel-level drawings. Preprocessing and postprocessing are also proposed to ensure the stability and accuracy of the shape mask segmentation. Then, based on the obtained shape masks, a vector extraction network guided by heatmaps is designed to extract structural vectors by fusing the features from node heatmap and skeleton heatmap, respectively. Compared with the state-of-the-art methods, experiment results illustrate that the proposed semantic segmentation method can effectively eliminate the interference of many elements on drawings to segment the shape masks effectively, meanwhile, the model trained by the proposed vector extraction network can accurately extract the vectors such as nodes and line connections, avoiding redundant vector detection. The proposed method lays a solid foundation for automatic 3D model reconstruction and contributes to technological advancements in relevant fields. 展开更多
关键词 Design drawings semantic segmentation deep learning vector extraction DIGITIZATION 3D modeling
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Evaluation of scale effects in physical modeling of combined ogee and sharp-crested weir flow using a 3D CFD model
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作者 James Zulfan Bobby Minola Ginting Ravi Anthony Tartandyo 《Water Science and Engineering》 2025年第2期225-235,共11页
Research on scale effects on flows over weirs has been conducted on a limited basis, primarily focusing on flows upstream of a single-type weir, such as ogee, broad-crested, and sharp-crested (linear and non-linear) w... Research on scale effects on flows over weirs has been conducted on a limited basis, primarily focusing on flows upstream of a single-type weir, such as ogee, broad-crested, and sharp-crested (linear and non-linear) weirs. However, the scale effects downstream of these single-type weirs have not been thoroughly investigated. This study examined the scale effects on flows over a combined weir system consisting of an ogee weir and a sharp-crested weir, both upstream and downstream, utilizing physical modeling at a 1:33.33 scale based on Froude similarity and three-dimensional (3D) computational fluid dynamics (CFD) modeling. The sharp-crested weir in this study was represented by two sluice gates that remain closed and submerged during flood events. The experimental data confirmed that the equivalent discharge coefficients of the combined weir system behaved similarly to those of a sharp-crested weir across various H/P (where H is the total head, and P is the weir height) values. However, scale effects on the discharge rating curve due to surface tension and viscosity could only be minimized when H/P > 0.4, Re > 26 959, and We > 240 (where Re and We are the Reynolds and Weber numbers, respectively), provided that the water depth exceeded 0.042 m above the crest. Additionally, Re greater than 4 × 104 was necessary to minimize scale effects caused by viscosity in flows in the spillway channel and stilling basin (with baffle blocks). The limiting criteria aligned closely with existing literature. This study offers valuable insights for practical applications in hydraulic engineering in the future. 展开更多
关键词 3D CFD Ogee weir Physical modeling Sharp-crested weir Sluice gate Scale effects
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A novel heuristic pathfinding algorithm for 3D security modeling and vulnerability assessment
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作者 Jun Yang Yue-Ming Hong +2 位作者 Yu-Ming Lv Hao-Ming Ma Wen-Lin Wang 《Nuclear Science and Techniques》 2025年第5期152-166,共15页
Vulnerability assessment is a systematic process to identify security gaps in the design and evaluation of physical protection systems.Adversarial path planning is a widely used method for identifying potential vulner... Vulnerability assessment is a systematic process to identify security gaps in the design and evaluation of physical protection systems.Adversarial path planning is a widely used method for identifying potential vulnerabilities and threats to the security and resilience of critical infrastructures.However,achieving efficient path optimization in complex large-scale three-dimensional(3D)scenes remains a significant challenge for vulnerability assessment.This paper introduces a novel A^(*)-algorithmic framework for 3D security modeling and vulnerability assessment.Within this framework,the 3D facility models were first developed in 3ds Max and then incorporated into Unity for A^(*)heuristic pathfinding.The A^(*)-heuristic pathfinding algorithm was implemented with a geometric probability model to refine the detection and distance fields and achieve a rational approximation of the cost to reach the goal.An admissible heuristic is ensured by incorporating the minimum probability of detection(P_(D)^(min))and diagonal distance to estimate the heuristic function.The 3D A^(*)heuristic search was demonstrated using a hypothetical laboratory facility,where a comparison was also carried out between the A^(*)and Dijkstra algorithms for optimal path identification.Comparative results indicate that the proposed A^(*)-heuristic algorithm effectively identifies the most vulnerable adversarial pathfinding with high efficiency.Finally,the paper discusses hidden phenomena and open issues in efficient 3D pathfinding for security applications. 展开更多
关键词 Physical protection system 3D modeling and simulation Vulnerability assessment A^(*)Heuristic Pathfinding Dijkstra algorithm
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Error modeling of 3-RSR parallel robot based on D-H transformation matrix 被引量:3
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作者 李瑞琴 杨斌 《Journal of Measurement Science and Instrumentation》 CAS 2014年第3期53-59,2,共7页
By selecting any one limb of 3-RSR parallel robot as a research object, the paper establishes a position and orienta- tion relationship matrix between the moving platform and the base by means of Denavit-Hartenberg (... By selecting any one limb of 3-RSR parallel robot as a research object, the paper establishes a position and orienta- tion relationship matrix between the moving platform and the base by means of Denavit-Hartenberg (D-H) transformation matrix. The error mapping model is derived from original error to the error of the platform by using matrix differential method. This model contains all geometric original errors of the robot. The nonlinear implicit function relation between po- sition and orientation error of the platform and the original geometric errors is simplified as a linear explicit function rela- tion. The results provide a basis for further studying error analysis and error compensation. 展开更多
关键词 error modeling 3-RSR parallel robot Denavit-Hartenberg (D-H) transformation matrix
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Study upon Modeling and Visualization of 3D Geologic Body Based on Generalized Tri-Prism 被引量:3
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作者 唐勇 江南 《Journal of Landscape Research》 2010年第9期1-3,55,共4页
According to the characteristics of bore data,a model of 3D geologic body with generalized tri-prism as the primitive modeling element is constructed while the modeling process and key algorithms of modeling are prese... According to the characteristics of bore data,a model of 3D geologic body with generalized tri-prism as the primitive modeling element is constructed while the modeling process and key algorithms of modeling are presented here in detail.Using this method,the original bore data go through Delaunay triangulation to generate irregular triangular network on the surface,and then links stratum segments on the adjoining bores in session to form tri-prisms which would be pinched out.Finally stratified 3D geologic body model is built by an iterated search which searches for consecutive layer of the same property.The result shows that this method can effectively simulate stratified stratum modeling. 展开更多
关键词 3D geological body modeling VISUALIZATION GENERALIZED tri-prism DELAUNAY triangulation
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3-D Geological Modeling-Concept,Methods and Key Techniques 被引量:19
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作者 PAN Mao LI Zhaoliang +2 位作者 GAO Zhongbo YANG Yang WU Gengyu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第4期1031-1036,共6页
3-D geological modeling plays an increasingly important role in Petroleum Geology, Mining Geology and Engineering Geology. The complexity of geological conditions requires different modeling methods in different situa... 3-D geological modeling plays an increasingly important role in Petroleum Geology, Mining Geology and Engineering Geology. The complexity of geological conditions requires different modeling methods in different situations. This paper summarizes the general concept of geological modeling; compares the characteristics of borehole-based modeling, cross-section based modeling and multi- source interactive modeling; analyses key techniques in 3-D geological modeling; and highlights the main difficulties and directions of future studies. 展开更多
关键词 3-D geological modeling geological interpretation methods of modeling quality of models
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Application of 3-D Geoscience Modeling Technology for the Estimation of Solid Mineral Reserves 被引量:17
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作者 PAN Mao LI Jun +1 位作者 WANG Zhangang JIN Jiangjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期655-660,共6页
Applying new approaches, methods, and technologies for the estimation of reserves can effectively improve the efficiency and accuracy of assessments of solid mineral resources. After analyzing the development of 3-D g... Applying new approaches, methods, and technologies for the estimation of reserves can effectively improve the efficiency and accuracy of assessments of solid mineral resources. After analyzing the development of 3-D geoscience modeling technology (3-D GMT), this paper discusses the application of 3-D GMT for the estimation of solid mineral reserves, emphatically introducing its workflow and two key technologies, 3-D orebody surface modeling, and property modeling. Moreover, the paper analyzes the limitations of traditional methods, such as the section method and geological block method, and points out the advantages of 3-D GMT: building more accurate 3-D orebody models, expressing the internal inhomogeneous attributes of an orebody, reducing the potential for errors in the estimation of reserves, and implementing dynamic estimations of reserves. 展开更多
关键词 3-D geoscience modeling solid mineral resource estimation of reserves surface modeling property modeling
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Modeling rock specimens through 3D printing: Tentative experiments and prospects 被引量:24
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作者 Quan Jiang Xiating Feng +3 位作者 Lvbo Song Yahua Gong Hong Zheng Jie Cui 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第1期101-111,共11页
Current developments in 3D printing (3DP) technology provide the opportunity to produce rock-like specimens and geotechnical models through additive man- ufacturing, that is, from a file viewed with a computer to a ... Current developments in 3D printing (3DP) technology provide the opportunity to produce rock-like specimens and geotechnical models through additive man- ufacturing, that is, from a file viewed with a computer to a real object. This study investigated the serviceability of 3DP products as substitutes for rock specimens and rock-type materials in experimental analysis of deformation and failure in the laboratory. These experiments were performed on two types of materials as follows: (1) compressive experiments on printed sand-powder specimens in different shapes and structures, including intact cylinders, cylinders with small holes, and cuboids with pre-existing cracks, and (2) com- pressive and shearing experiments on printed polylactic acid cylinders and molded shearing blocks. These tentative tests for 3DP technology have exposed its advantages in produc- ing complicated specimens with special external forms and internal structures, the mechanical similarity of its product to rock-type material in terms of deformation and failure, and its precision in mapping shapes from the original body to the trial sample (such as a natural rock joint). These experiments and analyses also successfully demonstrate the potential and prospects of 3DP technology to assist in the deformation and failure analysis of rock-type materials, as well as in the sim- ulation of similar material modeling experiments. 展开更多
关键词 Rock mechanics Similar material 3Dprinting Geotechnical model Deformation and failure
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The parallel 3D magnetotelluric forward modeling algorithm 被引量:28
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作者 Tan Handong Tong Tuo Lin Changhong 《Applied Geophysics》 SCIE CSCD 2006年第4期197-202,共6页
The workload of the 3D magnetotelluric forward modeling algorithm is so large that the traditional serial algorithm costs an extremely large compute time. However, the 3D forward modeling algorithm can process the dat... The workload of the 3D magnetotelluric forward modeling algorithm is so large that the traditional serial algorithm costs an extremely large compute time. However, the 3D forward modeling algorithm can process the data in the frequency domain, which is very suitable for parallel computation. With the advantage of MPI and based on an analysis of the flow of the 3D magnetotelluric serial forward algorithm, we suggest the idea of parallel computation and apply it. Three theoretical models are tested and the execution efficiency is compared in different situations. The results indicate that the parallel 3D forward modeling computation is correct and the efficiency is greatly improved. This method is suitable for large size geophysical computations. 展开更多
关键词 Magnetotelluric 3D forward modeling MPI parallel programming design 3D staggered-grid finite difference method parallel algorithm.
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Cavity 3D modeling and correlative techniques based on cavity monitoring 被引量:25
20
作者 罗周全 刘晓明 +2 位作者 张保 鹿浩 李畅 《Journal of Central South University of Technology》 EI 2008年第5期639-644,共6页
According to the mining method for Dongguashan Copper Mine and Tongkeng Mine in China, and with the help of the cavity monitoring system(CMS) and mining software Surpac, the 3D cavity models were established exactly... According to the mining method for Dongguashan Copper Mine and Tongkeng Mine in China, and with the help of the cavity monitoring system(CMS) and mining software Surpac, the 3D cavity models were established exactly. A series of correlative techniques for calculating stope over-excavation and under-excavation, stope dilution and ore loss rates, and the blasting design of the pillar with complicated irregular boundaries were developed. These techniques were applied in Dongguashan Copper Mine and Tongkeng Mine successfully. Using these techniques, the dilution rates of stopes 52-2^#, 52-6^#, 52-8^#and 52-10^# of Dongguashan Copper Mine are calculated to be 2.12%, 8.46%, 12-67% and 10.68%, respectively, and the ore loss rates of stopes 52-6^# and 5-8^# are 4.41% and 3.70%, severally. Furthermore, according to the design accomplished by the technique for a pillar of Tongkeng Mine with irregular boundary, the volume, total length of boreholes and the dynamite quantity of the pillar are computed to be 1.2 ×10^4 m^3, 2.98 km and 10.97 t, correspondingly. 展开更多
关键词 cavity 3D modeling cavity monitoring system STOPE DILUTION loss rate pillar blasting
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