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Material driven workability simulation by FEM including 3D processing maps for magnesium alloy 被引量:2
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作者 刘娟 李居强 +2 位作者 崔振山 欧立安 阮立群 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期3011-3019,共9页
The three-dimensional (3D) processing maps considering strain based on the two-dimensional (2D) processing maps proposed by PRASAD can describe the distribution of the efficiency of power dissipation and flow inst... The three-dimensional (3D) processing maps considering strain based on the two-dimensional (2D) processing maps proposed by PRASAD can describe the distribution of the efficiency of power dissipation and flow instability regions at various temperatures, strain rates and strains, which exhibit intrinsic workability related to material itself. Finite element (FE) simulation can obtain the distribution of strain, strain rate, temperature and die filling status, which indicates state-of-stress (SOS) workability decided by die shape and different processing conditions. On the basis of this, a new material driven analysis method for hot deformation was put forward by the combination of FE simulation with 3D processing maps, which can demonstrate material workability of the entire hot deformation process including SOS workability and intrinsic workability. The hot forging process for hard-to-work metal magnesium alloy was studied, and the 3D thermomechanical FE simulation including 3D processing maps of complex hot forging spur bevel gear was first conducted. The hot forging experiments were carried out. The results show that the new method is reasonable and suitable to determine the aoorooriate nrocess narameters. 展开更多
关键词 material driven workability simulation 3d processing maps magnesium alloy hot forging
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D-塔格糖3-差向异构酶的理性设计与机制解析
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作者 郭丁钰 魏婉清 +4 位作者 宋伟 吴静 闻建 胡贵鹏 刘立明 《食品与发酵工业》 北大核心 2025年第4期58-64,共7页
D-阿洛酮糖是一种在自然界中存在极少的酮糖,因其具有与蔗糖相近的甜度但热量更低而备受关注。然而,D-阿洛酮糖的高效生物合成仍然面临挑战,是由于用于生产的酮糖3-差向异构酶的热稳定性较差。该研究通过理性设计,引入二硫键和属性嫁接... D-阿洛酮糖是一种在自然界中存在极少的酮糖,因其具有与蔗糖相近的甜度但热量更低而备受关注。然而,D-阿洛酮糖的高效生物合成仍然面临挑战,是由于用于生产的酮糖3-差向异构酶的热稳定性较差。该研究通过理性设计,引入二硫键和属性嫁接策略,成功获得了热稳定性更高的最佳突变体M03。最佳突变体M03的T m值从52.7℃提高到69.4℃;在无需外源添加金属离子的条件下,55℃时半衰期延长至254.3 min,是野生型的54.1倍;通过分子动力学模拟和结构分析揭示了性能提升的详细机制。该研究为工业化生产D-阿洛酮糖提供了一个有潜力的突变菌株。 展开更多
关键词 d-阿洛酮糖 d-塔格糖3-差向异构酶 热稳定性 蛋白质工程改造 分子动力学模拟
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Secure Image Communication Using Galois Field,Hyper 3D Logistic Map,and B92 Quantum Protocol
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作者 De Rosal Ignatius Moses Setiadi Nova Rijati +2 位作者 Ahmad Rofiqul Muslikh Bonifacius Vicky Indriyono Aceng Sambas 《Computers, Materials & Continua》 SCIE EI 2024年第12期4435-4463,共29页
In this paper,we propose a novel secure image communication system that integrates quantum key distribution and hyperchaotic encryption techniques to ensure enhanced security for both key distribution and plaintext en... In this paper,we propose a novel secure image communication system that integrates quantum key distribution and hyperchaotic encryption techniques to ensure enhanced security for both key distribution and plaintext encryption.Specifically,we leverage the B92 Quantum Key Distribution(QKD)protocol to secure the distribution of encryption keys,which are further processed through Galois Field(GF(28))operations for increased security.The encrypted plaintext is secured using a newly developed Hyper 3D Logistic Map(H3LM),a chaotic system that generates complex and unpredictable sequences,thereby ensuring strong confusion and diffusion in the encryption process.This hybrid approach offers a robust defense against quantum and classical cryptographic attacks,combining the advantages of quantum-level key distribution with the unpredictability of hyperchaos-based encryption.The proposed method demonstrates high sensitivity to key changes and resilience to noise,compression,and cropping attacks,ensuring both secure key transmission and robust image encryption. 展开更多
关键词 Galois field hyper 3d logistic map hyperchaotic map image security improved logistic map secure communication quantum security
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Self-similarity Based Editing of 3D Surface Textures Using Height and Albedo Maps
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作者 DONG Junyu REN Jing CHEN Guojiang 《Journal of Ocean University of China》 SCIE CAS 2007年第2期209-212,共4页
This paper presents an inexpensive method for self-similarity based editing of real-world 3D surface textures by using height and albedo maps. Unlike self-similarity based 2D texture editing approaches which only make... This paper presents an inexpensive method for self-similarity based editing of real-world 3D surface textures by using height and albedo maps. Unlike self-similarity based 2D texture editing approaches which only make changes to pixel color or inten- sity values, this technique also allows surface geometry and reflectance of the captured 3D surface textures to be edited and relit us- ing illumination conditions and viewing angles that differ from those of the original. A single editing operation at a given location affects all similar areas and produces changes on all images of the sample rendered under different conditions. Since surface height and albedo maps can be used to describe seabed topography and geologic features, which play important roles in many oceanic proc- esses, the proposed method can be effectively employed in applications regarding visualization and simulation of oceanic phenom- ena. 展开更多
关键词 3d surface texture SELF-SIMILARITY texture editing bump mapping visualization virtual reality
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Linking a Simulated Annealing Based Optimization Model with PHT3D Simulation Model for Chemically Reactive Transport Processes to Optimally Characterize Unknown Contaminant Sources in a Former Mine Site in Australia
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作者 Bithin Datta Claire Petit +2 位作者 Marine Palliser Hamed K. Esfahani Om Prakash 《Journal of Water Resource and Protection》 2017年第5期432-454,共23页
Historical mining activities often lead to continuing wide spread contaminants in both groundwater and surface water in previously operational mine site areas. The contamination may continue for many years after closi... Historical mining activities often lead to continuing wide spread contaminants in both groundwater and surface water in previously operational mine site areas. The contamination may continue for many years after closing down the mining activities. The essential first step for sustainable management of groundwater and development of remediation strategies is the unknown contaminant source characterization. In a mining site, there are multiple species of contaminants involving complex geochemical processes. It is difficult to identify the potential sources and pathways incorporating the chemically reactive multiple species of contaminants making the source characterization process more challenging. To address this issue, a reactive transport simulation model PHT3D is linked to a Simulated Annealing based the optimum decision model. The numerical simulation model PHT3D is utilized for numerically simulating the reactive transport process involving multiple species in the former mine site area. The simulation results from the calibrated PHT3D model are illustrated, with and without incorporating the chemical reactions. These comparisons show the utility of using a reactive, geochemical transport process’ simulation model. Performance evaluation of the linked simulation optimization methodology is evaluated for a contamination scenario in a former mine site in Queensland, Australia. These performance evaluation results illustrate the applicability of linked simulation optimization model to identify the source characteristics while using PHT3D as a numerical reactive chemical species’ transport simulation model for the hydro-geochemically complex aquifer study area. 展开更多
关键词 Groundwater CONTAMINATION Source Characterization PHT3d Linked simulATION Optimization Methodology Chemically Reactive Transport simulATION MINE SITE CONTAMINATION simulated Annealing
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Influence of Adoptment of Geocentric 3D Coordinate System on Chinese Existent Maps
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作者 CHENJunyong DANGYamin 《Geo-Spatial Information Science》 2005年第2期79-84,103,共7页
If a geocentric 3D coordinate system is adopted in China to replace 2D non-geocentric coordinate system, the coordinates of the surface points will be changed accordingly. The influences on the current maps of China, ... If a geocentric 3D coordinate system is adopted in China to replace 2D non-geocentric coordinate system, the coordinates of the surface points will be changed accordingly. The influences on the current maps of China, especially the topographic maps, are discussed due to the replacement of the coordinate systems. Taking the replacement of Xi’an 80 coordinate system by GRS80 for a numerical example, this paper analyzes the changes of latitude, longitude, Gauss plane coordinates of the surface points, as well as the orientation and the length changes between the points on the map, including the changes of map border lines and sheet corner points. 展开更多
关键词 replacement of coordinate system map geocentric 3d coordinate system
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3DV quality model based depth maps for view synthesis in FTV system
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作者 张秋闻 安平 +2 位作者 张艳 张兆杨 王元庆 《Journal of Shanghai University(English Edition)》 CAS 2011年第4期335-341,共7页
Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts ... Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts in the synthesized views. To solve this problem, a 3D video quality model base depth maps (D-3DV) for virtual view synthesis and depth map coding in the FTV applications is proposed. First, the relationships between distortions in coded depth map and rendered view are derived. Then, a precisely 3DV quality model based depth characteristics is develop for the synthesized virtual views. Finally, based on D-3DV model, a multilateral filtering is applied as a pre-processed filter to reduce rendering artifacts. The experimental results evaluated by objective and subjective methods indicate that the proposed D-3DV model can reduce bit-rate of depth coding and achieve better rendering quality. 展开更多
关键词 free-viewpoint television (FTV) 3d video quality model base depth maps d-3dV) view synthesis
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基于AutoDesk Map 3D的土方量计算 被引量:5
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作者 徐志刚 高鹏 +1 位作者 张金雷 纪王凌 《江西理工大学学报》 CAS 2013年第1期47-50,共4页
为了提高土方量计算的精度及效率,文中提出了基于AutoDesk Map 3D的土方量计算方法.该方法是以AutoDesk Map 3D作为软件开发平台,建立土方量计算原始表面与设计表面的精确地形模型,计算两个曲面之间的组合体积来实现土方量的计算.文中... 为了提高土方量计算的精度及效率,文中提出了基于AutoDesk Map 3D的土方量计算方法.该方法是以AutoDesk Map 3D作为软件开发平台,建立土方量计算原始表面与设计表面的精确地形模型,计算两个曲面之间的组合体积来实现土方量的计算.文中通过对比分析提出了采用混合表示节点及三角形邻接关系的数据结构,建立狄洛尼三角网,然后通过加入约束条件建立带约束条件的狄洛尼三角网来模拟地形模型.根据提出的算法编写程序代码,利用VBA对系统进行开发,生成工程文件,然后加载到Autodesk Map 3D软件平台,建立计算土方量模块. 展开更多
关键词 土方量计算 map 3d dTM
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玩转3D地图——微软3D Maps全接触
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《科技新时代(下半月)》 2007年第4期114-114,共1页
各大搜寻器均提供网上地图服务。然而所提供的服务实在太相似。Microsoft就在这方面追求突破,在其Live Search内的Maps功能中,提供与别不同的3D地图服务。 微软Live Search功能下提供多项服务,用户在选择“Maps”选项后便可开始搜... 各大搜寻器均提供网上地图服务。然而所提供的服务实在太相似。Microsoft就在这方面追求突破,在其Live Search内的Maps功能中,提供与别不同的3D地图服务。 微软Live Search功能下提供多项服务,用户在选择“Maps”选项后便可开始搜寻地址,按“3DMaps”按钮时系统会通知用户安装外挂程序。程序安装完毕后,再进入Live Search网站,首先你需要进行3项初始化设定,用户可以选择三维、一般及最佳三类效果类型,T3建议大家选择最佳效果选项,以便在地图中显示建筑物的完整外貌。之后用户就可以按“Ctrl”键,并通过移动鼠标来平移地图。 在浏览立体地图时,地图浏览器左半部分可以支持立体显示的地点,用户只要点击地点,地图浏览器便会显示该地点的立体地图。现在,你可以试着靠近建筑物,居然可以清楚的看到建筑物门窗哟,而运动场的纹理也清晰可见。 展开更多
关键词 地图服务 maps 3d 微软 Microsoft “Ctrl”键 立体显示 程序安装
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Temperature Distributions in Single Cell of Polymer Electrolyte Fuel Cell Simulated by an 1D Multi-plate Heat-Transfer Model and a 3D Numerical Simulation Model
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作者 Akira Nishimura Masashi Baba +3 位作者 Kotaro Osada Takenori Fukuoka MasafumiHirota Eric Hu 《Journal of Energy and Power Engineering》 2015年第8期687-704,共18页
The purpose of this study is to verify an 1D multi-plate heat-transfer model estimating the temperature distribution on the interface between polymer electrolyte membrane and catalyst layer at cathode in single cell o... The purpose of this study is to verify an 1D multi-plate heat-transfer model estimating the temperature distribution on the interface between polymer electrolyte membrane and catalyst layer at cathode in single cell of polymer electrolyte fuel cell, which is named as reaction surface in this study, with a 3D numerical simulation model solving many governing equations on the coupling phenomena in the cell. The results from both models/simulations agreed well. The effects of initial operation temperature, flow rate, and relative humidity of supply gas on temperature distribution on the reaction surface were also investigated. It was found in both 1D and 3D simulations that, the temperature rise (i.e., Treact-Tini) of the reaction surface from initial operation temperature at 70℃ was higher than that at 80℃ irrespective of flow rate of supply gas. The effect of relative humidity of supply gas on Treact- Tini near the inlet of the cell was small. Compared to the previous studies conducted under the similar operation conditions, the Treact - Tini calculated by 1D multi-plate heat-transfer model in this study as well as numerical simulation using 3D model was reasonable. 展开更多
关键词 Polymer electrolyte fuel cell 1d multi-plate heat-transfer model 3d numerical simulation model temperaturedistribution.
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基于AutoDesk Map 3D的DTM建立及等高线绘制研究 被引量:5
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作者 陈绍杰 徐志刚 《测绘通报》 CSCD 北大核心 2008年第8期36-39,共4页
介绍利用递归生长法、凸闭包收缩、分割-归并法相结合的算法快速生成TIN,并以断裂线、地性线、建筑物边界为约束条件,最终生成具有约束的不规则三角网。然后,以点文件数据为原始数据,基于AutoDesk Map 3D基础软件和上述算法,通过二次开... 介绍利用递归生长法、凸闭包收缩、分割-归并法相结合的算法快速生成TIN,并以断裂线、地性线、建筑物边界为约束条件,最终生成具有约束的不规则三角网。然后,以点文件数据为原始数据,基于AutoDesk Map 3D基础软件和上述算法,通过二次开发功能,使生成的地形模型得到优化,并自动绘制等高线图。 展开更多
关键词 数字地形模型 曲面 AUTOdESK map 3d 等高线
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Autodesk Map 3D在地理基础数据采集中的应用 被引量:2
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作者 陈绍杰 徐志刚 高鹏 《测绘工程》 CSCD 2008年第5期37-40,共4页
Autodesk Map 3D具有为专业制图员和地理信息系统(GIS)专业人士进行设计的功能强大的制图功能,它可以作为GIS前端数据采集软件。介绍Autodesk Map 3D 2005及其在采集DTM、等高线地理基础数据方面的应用,并以点文件为数据源,介绍DTM的建... Autodesk Map 3D具有为专业制图员和地理信息系统(GIS)专业人士进行设计的功能强大的制图功能,它可以作为GIS前端数据采集软件。介绍Autodesk Map 3D 2005及其在采集DTM、等高线地理基础数据方面的应用,并以点文件为数据源,介绍DTM的建立、等高线的绘制、DTM编辑及特征线的应用。 展开更多
关键词 AUTOdESK map 3d GIS 等高线
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MRI T_2 star mapping、T_1 images与3D DESS融合图在隐匿性膝关节软骨损伤中的应用 被引量:4
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作者 范伟雄 杨志企 +3 位作者 程凤燕 黄健 于昭 侯文忠 《临床医学工程》 2017年第4期437-439,共3页
目的探讨T_2 star mapping、T_1 images与3D DESS融合伪彩图在关节软骨损伤中的诊断价值。方法对26例关节软骨损伤患者行T_2 star mapping、T_1 images和3D DESS扫描,并将T_1 images、T_2 star mapping与3D DESS图像融合,评价患者股骨... 目的探讨T_2 star mapping、T_1 images与3D DESS融合伪彩图在关节软骨损伤中的诊断价值。方法对26例关节软骨损伤患者行T_2 star mapping、T_1 images和3D DESS扫描,并将T_1 images、T_2 star mapping与3D DESS图像融合,评价患者股骨、胫骨、髌骨关节软骨损伤程度并与关节镜结果对比,计算融合伪彩图诊断软骨损伤的特异性、敏感性及与关节镜诊断结果一致性。结果 T_1 images-3D DESS融合伪彩图诊断关节软骨损伤的敏感度、特异度及Kappa值分别为92.8%、93.0%、0.769,T_2 star mapping-3D DESS融合伪彩图诊断关节软骨损伤的敏感度、特异度及Kappa值分别为91.4%、94.2%、0.787。结论 T_2 star mapping、T_1 images与3D DESS融合伪彩图在关节软骨早期损伤评价上优于关节镜。 展开更多
关键词 膝关节 关节软骨 磁共振成像 T2 star mapping T1 IMAGES 3d dESS
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3-D Simulation of FINFET 被引量:1
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作者 刘恩峰 刘晓彦 韩汝琦 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第9期909-913,共5页
An SOI MOSFET with FINFET structure is simulated using a 3 D simulator. I V characteristics and sub threshold characteristics,as well as the short channel effect(SCE) are carefully investigated.SCE can be well c... An SOI MOSFET with FINFET structure is simulated using a 3 D simulator. I V characteristics and sub threshold characteristics,as well as the short channel effect(SCE) are carefully investigated.SCE can be well controlled by reducing fin height.Good performance can be achieved with thin height,so fin height is considered as a key parameter in device design.Simulation results show that FINFETs present performance superior to conventional single gate devices. 展开更多
关键词 FINFET 3 d simulation short channel effect
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Autodesk Map 3D在数字测绘中的应用探讨 被引量:6
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作者 曾宪珪 熊涛 《南方冶金学院学报》 2005年第6期1-6,共6页
文章介绍了Autodesk Map 3D 2005的新特点,用户界面,主要下拉菜单及主要 功能,对它在数字测绘中的应用,主要讨论了等高线的绘制及其在土方量计算中的应用.
关键词 AUTOdESK map 3d 等高线 数字测绘平台 GIS
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Using 3D TCAD Simulation to Study Charge Collection of a p-n Junction in a 0.18μm Bulk Process
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作者 梁斌 陈书明 刘必慰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第9期1692-1697,共6页
Single event transient of a real p-n junction in a 0.18μm bulk process is studied by 3D TCAD simulation. The impact of voltage, temperature, substrate concentration, and LET on SET is studied. Our simulation results ... Single event transient of a real p-n junction in a 0.18μm bulk process is studied by 3D TCAD simulation. The impact of voltage, temperature, substrate concentration, and LET on SET is studied. Our simulation results demonstrate that biases in the range 1.62 to 1.98V influence DSET current shape greatly and total collected charge weakly. Peak current and charge collection within 2ns decreases as temperature increases,and temperature has a stronger influence on SET currents than on total charge. Typical variation of substrate concentration in modern VDSM processes has a negligible effect on SEEs. Both peak current and total collection charge increases as LET increases. 展开更多
关键词 charge collection p-n junction very deep sub-micro 3d device simulation RAdIATION
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基于SolidWorks Simulation的3D打印机机体静力学分析 被引量:2
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作者 吕蒙 牛晨旭 杨辰飞 《装备制造技术》 2018年第4期165-167,共3页
近年来,3D打印机作为一种高效率的成型设备被广泛的使用,然而,其高速性、高精度与高可靠性与其机体的轻量化设计存在一定的矛盾关系。通过SolidWorks软件对3D打印机机体进行轻量化设计,并使用集成的Simulation仿真软件对设计模型进行快... 近年来,3D打印机作为一种高效率的成型设备被广泛的使用,然而,其高速性、高精度与高可靠性与其机体的轻量化设计存在一定的矛盾关系。通过SolidWorks软件对3D打印机机体进行轻量化设计,并使用集成的Simulation仿真软件对设计模型进行快速静态力学分析,参照仿真结果对轻量化设计的模型进行验证与优化。通过集成化的三维建模软件和仿真软件,实现了3D打印机的模型设计和模型力学分析,验证了3D打印机设计的合理性和可靠性,为3D打印机的轻量化设计提供理论指导和修改建议,节省设备的研发周期和研发成本。 展开更多
关键词 SOLIdWORKS simulATION 3d打印机 静力学分析 机体结构
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Map3D在数字化瓦斯地质图中的应用研究 被引量:1
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作者 康宇 《煤》 2011年第11期20-22,共3页
瓦斯地质图是指导煤矿瓦斯治理的最重要的基础和技术,它还是瓦斯地质成果的具体体现。编绘瓦斯地质图是一项很重要的工作,文章以AutoCAD Map3D软件在某煤矿数字化瓦斯地质图的应用为例,分别演示数据库、信息查询和缓冲区分析等方面功能... 瓦斯地质图是指导煤矿瓦斯治理的最重要的基础和技术,它还是瓦斯地质成果的具体体现。编绘瓦斯地质图是一项很重要的工作,文章以AutoCAD Map3D软件在某煤矿数字化瓦斯地质图的应用为例,分别演示数据库、信息查询和缓冲区分析等方面功能,从而体现了Map3D在数字化瓦斯地质图方面的优势。 展开更多
关键词 瓦斯地质图 map3d 瓦斯治理
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立体测图数据在AutoCAD Map 3D中的自动预处理
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作者 初启凤 关明 颜小平 《测绘与空间地理信息》 2013年第12期245-246,249,共3页
从各种常用的摄影测量工作站的比较分析出发,针对原来的数字摄影测量工作站所生产的立体测图数据给后期数据编辑工作带来的数据拓扑问题,进行数据分析,并结合实际工作经验,给出一种在AutoCAD Map 3D软件中进行编辑前自动预处理的方法,... 从各种常用的摄影测量工作站的比较分析出发,针对原来的数字摄影测量工作站所生产的立体测图数据给后期数据编辑工作带来的数据拓扑问题,进行数据分析,并结合实际工作经验,给出一种在AutoCAD Map 3D软件中进行编辑前自动预处理的方法,以供读者参考。 展开更多
关键词 AUTOCAd map 3d 数字摄影测量工作站 预处理 拓扑 CLEANUP
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基于Map3D的规划图斑数据转换为系统数据的方法
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作者 刘宓 舒滨 杨钊 《城市勘测》 2016年第1期122-125,共4页
规划数据中的图斑多是以Auto CAD中的填充对象(Hatch)来表示的,这些填充对象无法直接转换为shp数据。本文讨论了基于Map3D平台将规划图斑数据转换为shp的方法,并对转换过程中出现的各种问题提出了相应的解决办法。
关键词 map3d GIS 规划图斑 SHAPEFILE
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