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3-D modeling of rock burst in pillar No. 19 of Fetr6 chromite mine 被引量:3
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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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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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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
关键词 自动化测量 三维模型 3-d 属性 库存 提取 自动化系统 林区
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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 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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A NOVEL 3-D MODEL FOR THE WATER CRESTING IN HORIZONTAL WELLS 被引量:5
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作者 LUO Wan-jing ZHOU Ying-fang WANG Xiao-dong 《Journal of Hydrodynamics》 SCIE EI CSCD 2008年第6期749-755,共7页
In the presence of bottom water, a drop in the reservoir pressure due to fluid production causes the aquifer water to expand and to flow into the reservoir. Therefore, hydrocarbon production from a well is limited by ... In the presence of bottom water, a drop in the reservoir pressure due to fluid production causes the aquifer water to expand and to flow into the reservoir. Therefore, hydrocarbon production from a well is limited by the critical flow rate. The main purpose of this study is to investigate the breakthrough time and the critical rate by using a novel 3-D horizontal well model. Based on the hypothesis that the horizontal well is located in any position of a circular reservoir with no-flow boundary on the top of the reservoir and constant pressure boundary at the bottom, the horizontal well has been regarded as an infinite conductivity line sink and then a 3-D steady-state flow model of the horizontal well is set up. A point sink pressure solution can be obtained with the Fourier transform. The result of the pressure distribution of the uniform flux horizontal well can be presented by means of the principle of superposition. According to the stable water cresting theory, this study confirms the stable height of water cresting and the critical rate. Meanwhile, it can re-confirm the breakthrough time at a specific rate. The output of a comparison between this 3-D model and the reservoir numerical simulator (Eclipse) shows the method presented here can be applied to investigate the behavior of a water cresting and to predict the breakthrough time at the bottom water driver reservoir. 展开更多
关键词 horizontal well bottom reservoir critical rate breakthrough time 3-d model
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3D打印实物模型在颈椎疾患住院医师规范化培训教学中的应用和探讨
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作者 王玉强 许建中 +6 位作者 谭洪宇 鲍恒 李宇 刘会范 王秀玲 马陶然 花卉 《中国毕业后医学教育》 2024年第5期369-372,共4页
目的探讨3 D打印实物模型在提高颈椎疾患住院医师规范化培训(简称住培)教学效果中的作用。方法选取参加骨科住培的颈椎疾患学习的住院医师80名为研究对象,随机分为两组,观察组(40人)以幻灯讲解加3 D打印实物模型教学,对照组(40人)采用... 目的探讨3 D打印实物模型在提高颈椎疾患住院医师规范化培训(简称住培)教学效果中的作用。方法选取参加骨科住培的颈椎疾患学习的住院医师80名为研究对象,随机分为两组,观察组(40人)以幻灯讲解加3 D打印实物模型教学,对照组(40人)采用幻灯讲解教学。课后即时和课后1月分别对住院医师的知识掌握情况和诊疗技术进行现场测试,利用问卷的形式对住院医师的满意度和参与兴趣(10分法)进行调查。结果课后即时观察组的知识掌握情况和对照组相当(P>0.05),但是观察组的诊疗技术测试成绩显著高于对照组(P<0.05),观察组的满意度和参与兴趣评分均显著高于对照组,两者对比差异有统计学意义(均P<0.05);课后1月时,观察组的知识掌握情况和诊疗技术测试成绩均显著高于对照组(均P<0.05)。结论3 D打印实物模型应用于颈椎疾患住培的带教中,可显著提高教学效果,提升住院医师的满意度和参与兴趣,值得在住培教学中推广。 展开更多
关键词 3D打印 实物模型 颈椎 教学 住院医师规范化培训
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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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Modelling of Quasi 3-D Groundwater Flow and Studying of Equivalent Drainage Boundary in Beihai Peninsula,Guangxi 被引量:2
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作者 Chen Chongxi Lin Min Li GuominChina University of Geosciences , Wuhan 430074Jiang Jianmin Ye Shanshi Wu NaidongGeology Bureau of Guangxi Autonomous Region , Naming 530023 《Journal of Earth Science》 SCIE CAS CSCD 1992年第1期109-119,共11页
This paper describes a quasi 3-D finite element model of the groundwater flow in two -aquifer system which is constructed from a sequence of aquifer flow equations coupled by leakage terms representing flow through th... This paper describes a quasi 3-D finite element model of the groundwater flow in two -aquifer system which is constructed from a sequence of aquifer flow equations coupled by leakage terms representing flow through the aquitard . It is applied to evaluate the maximum rate of groundwater resources exploited from the coastal aquifer without seawater intrusion . The main task in this model is to determine the drainage boundary of the aquifer extending under the sea . The information of the boundary can be obtained from the fluctuations of the groundwater level caused by sea-tide fluctuations . A new idea, Equivalent Drainage Boundary (EDB), is proposed and the corresponding methods , determining the EDB, are developed with tidal fluctuations data observed in boreholes . The quasi 3-D model and the methods determining EDB have been applied to the aquifer system of Beihai peninsula , Guangxi Autonomous Region of China for calculating the available groundwater resources . 展开更多
关键词 quad 3 - D model coastal aquifer Equivalent Drainage Boundary available groundwater resources Beihai peninsula .
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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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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 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 cm) 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 磁传感器 定位方法 胶囊 仪器
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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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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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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
关键词 模型验证 疏浚弃土 关键参数 3-d 环境影响评估 性能参数 现场测量 影响模型
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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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