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MODELING OF 3-D IMAGES AND SPACE MARKOV CUBIC MESH MODELS
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作者 钱唯 《Journal of Electronics(China)》 1990年第3期280-284,共5页
Three-dimensional(3-D)Markov cubic random mesh models are presented andproved in the form of two theorems in details.Its applications to the modeling and description of3-D images are described.The model presented here... Three-dimensional(3-D)Markov cubic random mesh models are presented andproved in the form of two theorems in details.Its applications to the modeling and description of3-D images are described.The model presented here is a appropriate mathematical tool for thesegmentation,modeling,classification and other processing.Finally,an example is given. 展开更多
关键词 markov CUBIC MESH model modeling 3-d IMAGE
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3-D Geological Modeling-Concept,Methods and Key Techniques 被引量:17
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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:15
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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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Numerical study on residual current and its impact on mass transport in the Hangzhou Bay and the Changjiang Estuary I. A3-D joint model of the Hangzhou Bay and the Changjiang Estuary 被引量:5
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作者 Zhu Shouxian 1,2 ,Shi Fengyan 1,Zhu Jianrong 1,Ding Pingxing 11 .StateKeyLaboratoryofEstuarineandCoastalResearch ,EastChinaNormalUniversity ,Shanghai 2 0 0 0 6 2 ,China   2.MeteorologyInstituteofthePLAScienceandEngineeringUniversity ,Nanjing 2 11 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2001年第1期1-13,共13页
A 3-D numerical model is set up in a large domain covering the Hangzhou Bay and the Changjiang Estuary based on the ECOM model in orthogonal curvilinear coordinates.The numerical schemes for baroclinic pressure gradie... A 3-D numerical model is set up in a large domain covering the Hangzhou Bay and the Changjiang Estuary based on the ECOM model in orthogonal curvilinear coordinates.The numerical schemes for baroclinic pressure gradient (BPG)terms and convective terms are improved in the paper according to the characteristics of velocity field and mass transport in the area.The model is validated by the simulations of residual current and salinity transport in the Hangzhou Bay and the Changjiang Estuary. 展开更多
关键词 3-d numerical model the Hangzhou Bay the Changjiang Estuary baroclinic pressure gradient convective
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Building 3-D Human Data Based on Handed Measurement and CNN
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作者 Bich Nguyen Binh Nguyen +3 位作者 Hai Tran Vuong Pham Le Nhi Lam Thuy Pham The Bao 《Computers, Materials & Continua》 SCIE EI 2023年第2期2431-2441,共11页
3-dimension(3-D)printing technology is growing strongly with many applications,one of which is the garment industry.The application of human body models to the garment industry is necessary to respond to the increasin... 3-dimension(3-D)printing technology is growing strongly with many applications,one of which is the garment industry.The application of human body models to the garment industry is necessary to respond to the increasing personalization demand and still guarantee aesthetics.This paper proposes amethod to construct 3-D human models by applying deep learning.We calculate the location of the main slices of the human body,including the neck,chest,belly,buttocks,and the rings of the extremities,using pre-existing information.Then,on the positioning frame,we find the key points(fixed and unaltered)of these key slices and update these points tomatch the current parameters.To add points to a star slice,we use a deep learning model tomimic the form of the human body at that slice position.We use interpolation to produce sub-slices of different body sections based on the main slices to create complete body parts morphologically.We combine all slices to construct a full 3-D representation of the human body. 展开更多
关键词 3-d human model deep learning INTERPOLATION
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3-D modeling of rock burst in pillar No. 19 of Fetr6 chromite mine 被引量:4
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作者 S. Dehghan K. Shahriar +1 位作者 P. Maarefvand K. Goshtasbi 《International Journal of Mining Science and Technology》 SCIE EI 2013年第2期237-242,共6页
Fetr6 is an underground mine in which chromite is extracted using stope and pillar mining method. Despite of all improving works such as roof supporting and replacing of ore pillars with concrete pillars, pillar No. 1... Fetr6 is an underground mine in which chromite is extracted using stope and pillar mining method. Despite of all improving works such as roof supporting and replacing of ore pillars with concrete pillars, pillar No. 19 failed and other pillars failed progressively as a domino effect and 4000 m2 of mine collapsed within a few minutes, consequently. For detail investigation, two 3-D numerical models were developed by 3Dec. The first, a base model, was used for estimation of stress on pillars just before failure and the other for investigation of rock burst in pillar No. 19. The results show that discontinuity parameters such as friction angle and shear stiffness is critical parameters in this pillar failure. In addition, it indicates that W/H ratio equal 0.3, the lack of ore extraction strategy and inadequate roof support are the major reasons for this failure. In this paper, the procedure of study was described. 展开更多
关键词 Rock burst Stope and pillar 3-d modeling 3Dec Domino effect Faryab mine
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Simulation of subcritical flow pattern in 180° uniform and convergent open-channel bends using SSIIM 3-D model 被引量:1
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作者 Rasool GHOBADIAN Kamran MOHAMMADI 《Water Science and Engineering》 EI CAS 2011年第3期270-283,共14页
In meandering rivers, the flow pattern is highly complex, with specific characteristics at bends that are not observed along straight paths. A numerical model can be effectively used to predict such flow fields. Since... In meandering rivers, the flow pattern is highly complex, with specific characteristics at bends that are not observed along straight paths. A numerical model can be effectively used to predict such flow fields. Since river bends are not uniform-some are divergent and others convergent-in this study, after the SSIIM 3-D model was calibrated using the result of measurements along a uniform 180° bend with a width of 0.6 m, a similar but convergent 180v bend, 0.6 m to 0.45 m wide, was simulated using the SSI1M 3-D numerical model. Flow characteristics of the convergent 180° bend, including lengthwise and vertical velocity profiles, primary and secondary flows, lengthwise and widtbwise slopes of the water surface, and the helical flow strength, were compared with those of the uniform 180° bend. The verification results of the model show that the numerical model can effectively simulate the flow field in the uniform bend. In addition, this research indicates that, in a convergent channel, the maximum velocity path at a plane near the water surface crosses the channel's centerline at about a 30° to 40° cross-section, while in the uniform bend, this occurs at about the 50° cross-section. The varying range of the water surface elevation is wider in the convergent channel than in the uniform one, and the strength of the helical flow is generally greater in the uniform channel than in the convergent one. Also, unlike the uniform bend, the convergent bend exhibits no rotational cell against the main direction of secondary flow rotation at the 135° cross-section. 展开更多
关键词 flow pattern numerical simulation convergent 180° bend SSIIM 3-d model
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3-D Magnetic Sensor Module for Locating and Tracking MEMS Swallowable Capsule Based on Scalar Form of Magnetic Dipole Model 被引量:2
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作者 WU Xu-dong PENG Cheng-lin HOU Wen-sheng ZHENG Xiao-lin FANG Xing 《Chinese Journal of Biomedical Engineering(English Edition)》 2007年第2期79-86,共8页
MEMS swallowable capsule is a novel technology in the non-invasive surgery. This technology provides a way to diagnose directly into the deep intestinal where the traditional invasive technology implemented, such as X... MEMS swallowable capsule is a novel technology in the non-invasive surgery. This technology provides a way to diagnose directly into the deep intestinal where the traditional invasive technology implemented, such as X-Ray, endoscopy. It is a key for us to locate and track the position of a MEMS capsule in clinical applications. To solve this problem, we implemented a magnetic sensor module based on the scalar form of the magnetic dipole model,which was designed with very small size (5.2 * 2. 1 * 1.2 em) and easy to assemble to satisfy the system requirement. Here we discuss in detail the principle of magnetic dipole model, rules of selecting sensor and functions of the module. Some trials are established to test the characteristic of the module. The results of the Cm experiment demonstrates that the module follows the rules of the new magnetic dipole model form. 展开更多
关键词 sealar form of magnetic dipole model 3-d magnetic sensor module
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3-D crustal-scale gravity model of the San Rafael Block and Payenia volcanic province in Mendoza,Argentina
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作者 Daniel Richarte Marianela Lupari +2 位作者 Agustina Pesce Silvina Nacif Mario Gimenez 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第1期239-248,共10页
The San Rafael Block(SRB)is part of one of the main retroarc volcanic provinces in southern Central Andes in Mendoza,Argentina.This block is located in the Andean foothills between the orogenic front and foreland base... The San Rafael Block(SRB)is part of one of the main retroarc volcanic provinces in southern Central Andes in Mendoza,Argentina.This block is located in the Andean foothills between the orogenic front and foreland basement uplifts of late Miocene age.In order to analyze the geochronological evolution of the Quaternary volcanism in the region,several geologic and geophysical studies have been conducted.Nevertheless,the crust,where the SRB is located,has not been well characterized yet.Based on gravimetric and magnetic data,together with isostatic and elastic thickness analyses,we modeled the crustal structure of the area.Information obtained has allowed us to understand the crust where the SRB and the Payenia volcanic province are located.Bouguer anomalies indicate that the SRB presents higher densities to the North of Cerro Nevado and Moho calculations suggest depths for this block between 40 and 50 km.Determinations of elastic thickness would indicate that the crust supporting the San Rafael Block presents values of approximately 10 km,being enough to support the block loading.However,in the Payenia region,elastic thickness values are close to zero due to the regional temperature increase. 展开更多
关键词 SAN Rafael BLOCK Payenia 3-d CRUSTAL model Asthenospheric wedge
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3-D MODELLING OF COMPUTER AIDED GARMENT DESIGN
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作者 杨建国 朱辉 《Journal of China Textile University(English Edition)》 EI CAS 1991年第1期7-10,共4页
This paper describes a method of the computer aided garment design,and discusses 3-D humanbody,wire frame modelling,approaches of expressing and a shading model of the 3-D garment.
关键词 COMPUTER aided design GARMENTS 3-d human BODY model wire FRAME GARMENT model
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3-D physical model in strong ground motion numerical simulation:A case study of Kunming basin
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作者 张冬丽 徐锡伟 +2 位作者 赵伯明 陈桂华 解廷伟 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第2期194-205,共12页
Seismic hazard assessment based on urban active faults can provide scientific bases for city planning and project construction, while numerical simulation of strong ground motion is an important method for seismic haz... Seismic hazard assessment based on urban active faults can provide scientific bases for city planning and project construction, while numerical simulation of strong ground motion is an important method for seismic hazard prediction and assessment. A 3-D physical model in conformity with real strata configuration of (mainly) the Quaternary is a prerequisite to ensure the reliability of the simulation results. In this paper, we give a detailed account of the technical scheme and process for creating a 3-D physical model in Kunming basin. The data used are synthe- sized from seismogeological data, borehole data, topographic data, digital elevation mode (DEM) data, seismic exploration results and wave velocity measurements. Strafigraphic division is based mainly on shear wave velocity, with strata sequence taken into consideration. The model construction is finally accomplished with ArcGIS and many relevant programming techniques via layer-by-layer stacking (in depth direction) of the adjacent medium interfaces (meshes). Meanwhile, a database of 3-D physical models is set up, which provides model data and parameters for strong ground motion simulation. Some processing methods and significant issues are also addressed in the paper in accordance with different types of exploration and experimental data. 展开更多
关键词 strong ground motion 3-d physical model QUATERNARY Kunming basin
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Research of the ATR system based on the 3-D models and L-M BP neural network
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作者 穆成坡 袁志杰 +2 位作者 王纪元 陈远迁 董清先 《Journal of Beijing Institute of Technology》 EI CAS 2014年第3期306-310,共5页
Automatic target recognition (ATR) is an important issue for military applications, the topic of the ATR system belongs to the field of pattern recognition and classification. In the paper, we present an approach fo... Automatic target recognition (ATR) is an important issue for military applications, the topic of the ATR system belongs to the field of pattern recognition and classification. In the paper, we present an approach for building an ATR system with improved artificial neural network to recog- nize and classify the typical targets in the battle field. The invariant features of Hu invariant moments and roundness were selected to be the inputs of the neural network because they have the invari- ances of rotation, translation and scaling. The pictures of the targets are generated by the 3-D mod- els to improve the recognition rate because it is necessary to provide enough pictures for training the artificial neural network. The simulations prove that the approach can be implement ed in the ATR system and it has a high recognition rate and can be applied in real time. 展开更多
关键词 ATR system 3-d models pictures generation pattern recognition Hu invariant round- ness BP neural networ
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Statistical Model of the 3-D Braided Composites Strength
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作者 XIAO Laiyuan ZUO Weiwei CAI Ganwei LIAO Daoxun 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期1077-1082,共6页
Based on the statistical model for the tensile statistical strength of unidirectional composite materials and the stress analysis of 3-D braided composites, a new method is proposed to calculate the tensile statistica... Based on the statistical model for the tensile statistical strength of unidirectional composite materials and the stress analysis of 3-D braided composites, a new method is proposed to calculate the tensile statistical strength of the 3-D braided compos- ites. With this method, the strength of 3-D braided composites can be calculated with very large accuracy, and the statistical parameters of 3-D braided composites can be determined. The numerical result shows that the tensile statistical strength of 3-D braided composites can be predicted using this method. 展开更多
关键词 3-d braided composites strength calculation statistical model
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Field-Based Automated Survey for Extracting Tree Inventory Attributes and 3-D Models in a Forested Area
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作者 Jasmee Jaafar Juazer Rizal Abdul Hamid Roslina ldris Azman All M. Habib 《Journal of Earth Science and Engineering》 2012年第9期561-570,共10页
Acquisition of tree inventory parameters such as tree position with respect to a local reference coordinate system, tree height, dbh (diameter breast height) and other associated tree attributes is a tedious process... Acquisition of tree inventory parameters such as tree position with respect to a local reference coordinate system, tree height, dbh (diameter breast height) and other associated tree attributes is a tedious process, time consuming, costly and labour intensive. An automatic collection and processing in the field could expedite the process of tree inventory survey and data management. The advent of handheld laser equipments such as the MDL LaserAce 300, should allow rapid acquisition of tree attributes. The instrument measures distances, differences in height and horizontal bearing automatically. This paper describes a study about the automated process of retrieving tree positions, their respective attributes and the creation of 3-D model (three-dimensional model). A software developed in-house known as ASSIST (automated spatial survey information system) was utilized together with the MI)I, LaserAce 300, being the hardware component of the automated system. The capability of MDL LaserAce 9300 in extracting information regarding tree inventory attributes and the 3-D model encompassing the study area was investigated. The results were checked against the data sets acquired by a total station traversing and tacheometric survey respectively. The accuracy of the horizontal and vertical position of points gathered was critically assessed. The accuracy of the MDL LaserAce 300 was found to be less than ±2 m for both planimetric (horizontal) and vertical (height) in the construction of the 3-D model. The study demonstrates the effectiveness of a field-based automation system as a viable option to support forest application requirement. 展开更多
关键词 Measuring laser tree inventory 3-d model.
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A 3-D in vitro tumor model for investigation of bacteria-mediated gene delivery
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作者 Nelita T.Elliott 《医用生物力学》 EI CAS CSCD 2010年第S1期1-2,共2页
Introduction Cancer is an attractive target of gene therapy and currently represents the disease in most clinical trials[1]. Strategies for cancer gene therapy include: (1) stimulation of immune responses to tumor cel... Introduction Cancer is an attractive target of gene therapy and currently represents the disease in most clinical trials[1]. Strategies for cancer gene therapy include: (1) stimulation of immune responses to tumor cells,(2) delivery of specific enzymes 展开更多
关键词 GENE A 3-d in vitro tumor model for investigation of bacteria-mediated gene delivery
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Investigation of Key Parameters for 3-D Dredging Plume Model Validation
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作者 Junsheng Jiang 《Journal of Shipping and Ocean Engineering》 2014年第5期129-139,共11页
Dredging plume dispersion studies, use dredging plume models to predict the fate of sediment plumes resulting from dredging activities and dredge spoil disposal. The model results are applied as input to environmental... Dredging plume dispersion studies, use dredging plume models to predict the fate of sediment plumes resulting from dredging activities and dredge spoil disposal. The model results are applied as input to environmental impact assessment of the proposed dredging, particularly those associated with suspended sediments and sedimentation. Model validation and performance are still not resolved because of the difficulty of site measurements and the understanding of the parameters used in the model. This paper presents a 3-D dredging plume model based on the MIKE3 software package to investigate parameters which affect the model performances. As a result of lack of site data for the public domain uses, the model scenarios are designed artificially for sensitive runs to identify the key parameters affecting plume behaviours. The factors include dredging spill rates using different dredging methods, equipment and sediment settling velocities. The influence of wave and wind effects combined with tidal forces on the sediment re-suspended rates and the advection/dispersion scales are also assessed. 展开更多
关键词 3-d dredging plume model settling velocity sediment measurement.
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3-D Modelling of the Confederation Bridge Using Data of Full Scale Tests
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作者 Lan Lin 《Open Journal of Civil Engineering》 2013年第3期18-25,共8页
Long-span bridges are special structures that require advanced analysis techniques to examine their performance. This paper presents a procedure developed to model the Confederation Bridge using 3-D beam elements. The... Long-span bridges are special structures that require advanced analysis techniques to examine their performance. This paper presents a procedure developed to model the Confederation Bridge using 3-D beam elements. The model was validated using the data collected before the opening of the bridge to the public. The bridge was instrumented to conduct fullscale static and dynamic tests. The static tests were to measure the deflection of the bridge pier while the dynamic tests to measure the free vibrations of the pier due to a sudden release of the static load. Confederation Bridge is one of the longest reinforced concrete bridges in the world. It connects the province of Prince Edward Island and the province of New Brunswick in Canada. Due to its strategic location and vital role as a transportation link between these two provinces, it was designed using higher safety factors than those for typical highway bridges. After validating the present numerical model, a procedure was developed to evaluate the performance of similar bridges subjected to traffic and seismic loads. It is of interest to note that the foundation stiffness and the modulus of elasticity of the concrete have significant effects on the structural responses of the Confederation Bridge. 展开更多
关键词 3-d Numerical modeling Finite Element Technique Static TESTS Dynamic TESTS ACCELERATION Time HISTORY FOURIER Analysis Full Scale Test SEISMIC Evaluation Confederation BRIDGE
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3-D技术有突破HP Direct Model为3-D加速
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《中国计算机用户》 1997年第16期71-71,共1页
关键词 3-d技术 HP公司 DIRECT model 3-d加速 图形软件技术
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Formation of the Tibetan Plateau during the India-Eurasia Convergence:Insight from 3-D Multi-Terrane Thermomechanical Modeling
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作者 Jile Chen Peimin Zhu +1 位作者 Yuefeng Yuan Guifan Chen 《Journal of Earth Science》 SCIE CAS CSCD 2024年第1期112-130,共19页
Various models exist to explain the formation of the Tibetan Plateau,including“tectonic escape”,“pure shear thickening”,“convective removal of the lithospheric mantle”,and“lower crustal flow”model.The first tw... Various models exist to explain the formation of the Tibetan Plateau,including“tectonic escape”,“pure shear thickening”,“convective removal of the lithospheric mantle”,and“lower crustal flow”model.The first two models are primarily constructed on pure mechanical models but are unable to reasonably explain the tension and shear phenomena inside the plateau.The latter two are rheological dynamic models based on deep geophysical observations.However,the spatial range of the lower crustal flow and its role in the plateau formation/uplift remain controversial.Five multi-terrane viscoplastic thermomechanical models were constructed to simulate the uplift and lithospheric structure change of the Tibetan Plateau during the post-collision stage(since 35 Ma)under the convergence of the Indian Plate.Results show that the plateau's formation begins with crustal thickening,blocked by strong terranes at the northern plateau,and expanded laterally to the east.The lithosphere thickens gradually and experiences delamination at its base,elevating temperature within the crust and forming partial melting layers in the central plateau.As convergence persists on the southern side,the northern plateau's lithosphere bends downward and undergoes delamination,further heating the crust and promoting the northward and eastward flow of partial melting layers,leading to secondary uplift around the plateau. 展开更多
关键词 3-d thermomechanical modeling Tibetan Plateau plateau uplift crustal flow
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A Higher-Efficient Non-Hydrostatic Finite Volume Model for Strong Three-Dimensional Free Surface Flows and Sediment Transport 被引量:1
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作者 LIU Xin MA Dian-guang ZHANG Qing-he 《China Ocean Engineering》 SCIE EI CSCD 2017年第6期736-746,共11页
In order to accurately simulate strong three-dimensional (3-D) free surface flows and sediment transport, the fully 3- D non-hydrostatic pressure models are developed based on the incompressible Navier-Stokes equati... In order to accurately simulate strong three-dimensional (3-D) free surface flows and sediment transport, the fully 3- D non-hydrostatic pressure models are developed based on the incompressible Navier-Stokes equations and convection-diffusion equation of sediment concentration with the mixing triangle and quadrilateral grids. The governing equations are discretized with the unstructured finite volume method in order to provide conservation properties of mass and momentum, and flexibility with practical application. It is shown that it is first-order accurate on nonuniform plane two-dimensional (2-D) grids and second-order accurate on uniform plane grids. A third-order approximation of the vertical velocity at the top-layer is applied. In such a way, free surface zero stress boundary condition is satisfied maturely, and very few vertical layers are needed to give an accurate solution even for complex discontinuous flow and short wave simulation. The model is applied to four examples to simulate strong 3-D free surface flows and sediment transport where non-hydrostatic pressures have a considerable effect on the velocity field. The newly developed model is verified against analytical solutions with an excellent agreement. 展开更多
关键词 higher-efficient NON-HYDROSTATIC strong 3-d free surface flows sediment transport 3-d numerical model
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