A Web-Based Approach for the Efficient Management of Massive Multi-source 3D Models

Effectively managing extensive,multi-source,and multi-level real-scene 3D models for responsive retrieval scheduling and rapid visualization in the Web environment is a significant challenge in the current development of real-scene 3D applications in China.In this paper,we address this challenge by reorganizing spatial and temporal information into a 3D geospatial grid.It introduces the Global 3D Geocoding System(G_(3)DGS),leveraging neighborhood similarity and uniqueness for efficient storage,retrieval,updating,and scheduling of these models.A combination of G_(3)DGS and non-relational databases is implemented,enhancing data storage scalability and flexibility.Additionally,a model detail management scheduling strategy(TLOD)based on G_(3)DGS and an importance factor T is designed.Compared with mainstream commercial and open-source platforms,this method significantly enhances the loadable capacity of massive multi-source real-scene 3D models in the Web environment by 33%,improves browsing efficiency by 48%,and accelerates invocation speed by 40%.

DATA MODEL AND VISUALIZATION OF 3D CITY LANDSCAPE BASED ON INTEGRATED DATABASES

Data acquisition and modeling are the two important, difficult and costful aspects in a Cybercity project. 2D-GIS is mature and can manage a lot of spatial data. Thus 3D-GIS should make the best of data and technology of 2D-GIS. Construction of a useful synthetic environment requires integration of multiple types of information like DEM, texture images and 3D representation of objects such as buildings. In this paper, the method for 3D city landscape data model and visualization based on integrated databases is presented. Since the data volume of raster are very huge, special strategies(for example, pyramid gridded method) must be adopted in order to manage raster data efficiently. Three different methods of data acquisition, the proper data structure and a simple modeling method are presented as well. At last, a pilot project of Shanghai Cybercity is illustrated.

Methods of 3D map storage based on geo-referenced image database

In order to store and manage a large amount of ground and indoor image data with high resolution, an integrated data management system needs to be developed. Possible strategies for this purpose were discussed together with initial test on the newly defined 3D maps. The features of such 3D maps, data organization, key techniques used for the map storage, such as image compression based on wavelet transformation, quadtree index, update and retrieval, were analyzed, with the goals of bringing some profits to the storage and management of the digital data in the visual construction of digital mine, digital city and digital community.

3D打印技术及典型病例数据库在骨科教学中的应用

目的探讨3D打印技术及典型病例数据库在五年制骨科临床教学中的应用和效果。方法按照教学大纲要求筛选合适的骨关节创伤病例,收集临床资料及X-ray、CT等影像资料建立数据库,应用数据库资料及3D打印实物实施教学,与传统教学方法比较授课效果。结果采用3D打印技术及典型病例数据库加深了学生对骨关节创伤知识的理解,有效提高了学习成绩。结论3D打印技术及典型病例数据库的建立,丰富了骨关节损伤的临床教学资源,并使之标准化,能有效提高教学效果,特别有助于学生临床技能的培养和胜任力的提升。

磷脂酰肌醇蛋白聚糖3和泛素D基因在肝细胞癌中的异常表达及其相互作用

目的利用基因组学和表观遗传组学分析工具,分析磷脂酰肌醇蛋白聚糖3(GPC3)和泛素D(UBD)在肝细胞癌(HCC)中的异常表达情况,以及两者对HCC患者预后的影响。方法利用ULCAN(http://ualan.path.uab.edu)和Gene Expression Profiling Interative Analysis(GEPIA)数据库,分析UBD和GPC3在正常肝组织和HCC组织的异常表达情况和甲基化水平,以及对HCC患者生存的影响。利用Gene Cards数据库分析UBD和GPC3的定位。利用STRING数据库对UBD和GPC3分别构建蛋白质互相作用(PPI)网络,并对UBD和GPC3进行基因注释。基于皮尔森相关系数,计算UBD和GPC3在HCC发生发展中的关联。结果UBD和GPC3在HCC组织中表达上调,启动子甲基化水平下降。UBD位于6p22.1,主要表达于细胞核;GPC3位于Xq26.2,主要表达于细胞膜、细胞外基质、内质网、溶酶体和高尔基体。富集分析显示,UBD主要与蛋白酶体活动相关:翻译后蛋白修饰、泛素化和去泛素化;GPC3主要参与黏多糖的生物合成和分解过程,介导的生物通路主要涉及癌症多聚糖、细胞外基质受体相互作用和细胞黏附分子。关联分析显示,UBD和GPC3成线性正相关,共同调控HCC的发生发展。预后分析显示,GPC3对HCC的预后有明显的影响。结论UBD和GPC3在HCC的表达均上调,甲基化水平均降低,GPC3对HCC的预后影响较大,或许可以作为预后评估的生物标志。

AutoCAD Map 3D在城镇地籍数据库建设中的应用

AutoCAD Map 3D软件是创建和管理空间数据的设计平台,在CAD和GIS之间架起了一座桥梁。强大的图形编辑和空间分析功能使地图制作更加方便快捷、开源的FDO数据访问技术使其能够直接无缝地访问存储于关系数据库、文件和基于web的空间数据。本文主要讨论AutoCAD Map 3D的功能和特点以及它在城镇地籍数据库建设中的应用。

GIS Applications for Building 3D Campus, Utilities and Implementation Mapping Aspects for University Planning Purposes

In city planning managing, the third dimension is becoming a necessity. Using 3D GIS modeling offers a flexible interactive system while providing one of the best visual interpretation of data which supports planning and decision processes for city planners. As a result, 3D GIS model expresses terrain features in an intuitive way which enhances the management and analysis of a proposed project through 3D visualization. This paper discusses the concept of 3D GIS modeling techniques using a simple procedure to generate a university campus model （real 3D GIS model） which will show the effectiveness of this approach. The 3D GIS model provides access to mapping data to support planning, design and data management. Intelligent GIS models and GIS tools help community planning and apply regional and discipline-specific standards. Integration of GIS spatial data with campus organization helps to improve quality, productivity and asset management. The following study built 3D GIS map and all utility information for AI al-Bayt University campus as an example. The primary objective is to improve data management （e.g., maps, plans, usage of facilities and services） and to develop methods using 3D spatial analysis for specific applications at the university.

水利水电工程3维地质建模系统一体化设计

针对水利水电3维地质建模软件在地质信息数据库与建模系统分离的弱点,提出结合3维地质数据库与3维建模软件交互设计的方法,并在CATIA软件上开发了适用于水利水电工程的3维地质建模平台。利用Microsoft SQL 8.0软件建立3维地质建模数据库,实现了数据的录入、查询、删除、EXCEL模版导入导出等功能;利用Visual Basic.net软件搭建3维地质建模平台,包括3维地质建模中所需的覆盖层、地质层、水文层、模型分析等基本模块,并将3维地质建模数据库嵌入到3维地质建模平台中,实现了钻孔数据的导入、虚拟钻孔以及3维地质模型任意剖切出图等功能,从而实现了3维地质建模数据库与3维建模平台一体化的设计理念。

3维场景中地名信息查询定位技术的研究与实现

研究了3维地形场景中地名信息的查询定位与可视化技术。基于1∶50000地名数据库,利用C#结合Di-rectX,运用面向对象技术从底层开发、设计和实现了3维地形场景中地名数据的查询定位与可视化功能。系统可快速模糊搜索、实时定位、动态调度地名数据,为其他各类专题信息的表达提供了一种有效的思路。

采油平台三维建模CAD系统的开发与应用

主要讨论了采油平台三维建模CAD系统的开发,即针对国内采油平台设计的现状,按照结构化生命周期法的原理,开发了一套适合采油平台设计使用的软件,并将研究成果成功应用于海上平台的三维图设计,显著提高了海上平台设计水平,提高了设计品质;在开发方法、设计分析方法、参数化建模、信息化管理、版本管理等方面的技术研究,也能适用于其他工程领域的设计,具有一定的推广实用价值。

基于SolidWorks工程机械三维模型库的开发与应用

通过对三维模型库在工程机械设计中的需求及其可行性分析,提出了基于Solidworks的工程机械三维模型库的建库思想,建立了基于Solidworks的三维模型库系统并通过网页设计和网站建设实现视频文件的网络浏览。

Design and Implementation of 3D Model Database for General-Purpose 3D GIS

To improve the reusability of three-dimensional （3D） models and simplify the complexity of natural scene reconstruction, this paper presents a 3D model database for universal 3D GIS. After the introduction of its extensible function architecture, accompanied by the conclusion of implicit spatial-temporal hierarchy of models in any reconstructed scene of 3D GIS for general purpose, several key issues are discussed in detail, such as the storage and management of 3D models and related retrieval and load method, as well as the interfaces for further on-demand development. Finally, the validity and feasibility of this model database are proved through its application in the development of 3D visualization system of railway operation.

锅炉房汽水系统CAD开发思路的探讨与实现

探讨了面向方案的概念在开发锅炉房汽水系统CAD软件中的具体应用 ,其中包括开放的设备数据库、三维设计环境、设计知识的组织和管理等 ,从而形成了一套完整的CAD软件的开发与实现模式。

A star-based data structure to store efficiently 3D topography in a database

For storing and modeling three-dimensional(3D)topographic objects(e.g.buildings,roads,dykes,and the terrain),tetrahedralizations have been proposed as an alternative to boundary representations.While in theory they have several advantages,current implementations are either not space efficient or do not store topological relationships(which makes spatial analysis and updating slow,or require the use of an expensive 3D spatial index).We discuss in this paper an alternative data structure for storing tetrahedralizations in a database management system(DBMS).It is based on the idea of storing only the vertices and stars of edges;triangles and tetrahedra are represented implicitly.It has been used previously in main memory,but not in a DBMS.We describe how to modify it to obtain an efficient implementation in a DBMS,and we describe how it can be used for modeling 3D topography.As we demonstrate with different real-world examples,the structure is compacter than known alternatives,it permits us to store attributes for any primitives,and has the added benefit of being topological,which permits us to query it efficiently.The structure can be easily implemented in most DBMS(we describe our implementation in PostgreSQL),and we present some of the engineering choices we made for the implementation.

The Use of Three-Dimensional Integrated Design System in Smart Substation Design

The traditional power design, construction, has been able to meet the requirements, but it has not been established engineering data database support and the correlation between the data is poor, due to inadequate coordination among design professionals, design easily lead to mistakes, field problems, and design results failed in all aspects of the project to be fully utilized. With the technology of three-dimensional integrated design system penetrates in all walks of life, the introduction of three-dimensional integrated design system substation design solutions and the application of common devices of State Grid Corporation in recent years, which provide technical conditions for the application of virtual reality technology in substation design. According to its own characteristics of substation project, we now propose prospect on virtual reality technology in substation design application.

Fluorometric Discrimination Technique of Phytoplankton Population Based on Wavelet Analysis

The discrete excitation-emission-matrix fluorescence spectra (EEMS) at 12 excitation wavelengths (400, 430, 450, 460, 470, 490, 500, 510, 525, 550, 570, and 590 nm) and emission wavelengths ranging from 600-750 nm were determined for 43 phytoplankton species. A two-rank fluorescence spectra database was established by wavelet analysis and a fluorometric discrimination technique for determining phytoplankton population was developed. For laboratory simulatively mixed samples, the samples mixed from 43 algal species (the algae of one division accounted for 25%, 50%, 75%, 85%, and 100% of the gross biomass, respectively), the average discrimination rates at the level of division were 65.0%, 87.5%, 98.6%, 99.0%, and 99.1%, with average relative contents of 18.9%, 44.5%, 68.9%, 73.4%, and 82.9%, respectively; the samples mixed from 32 red tide algal species (the dominant species accounted for 60%, 70%, 80%, 90%, and 100% of the gross biomass, respectively), the average correct discrimination rates of the dominant species at the level of genus were 63.3%, 74.2%, 78.8%, 83.4%, and 79.4%, respectively. For the 81 laboratory mixed samples with the dominant species accounting for 75% of the gross biomass (chlorophyll), the discrimination rates of the dominant species were 95.1% and 72.8% at the level of division and genus, respectively. For the 12 samples collected from the mesocosm experiment in Maidao Bay of Qingdao in August 2007, the dominant species of the 11 samples were recognized at the division level and the dominant species of four of the five samples in which the dominant species accounted for more than 80% of the gross biomass were discriminated at the genus level; for the 12 samples obtained from Jiaozhou Bay in August 2007, the dominant species of all the 12 samples were recognized at the division level. The technique can be directly applied to fluorescence spectrophotometers and to the developing of an in situ algae fluorescence auto-analyzer for phytoplankton population.

Integration of Digital Technologies into Underground Utility Asset Management

Installation, detection, maintenance, mapping, and management of underground utility assets present challenges to owners, engineers and contractors. Industry-wide practices include the use of geophysical and similar technologies to determine depth and location, and 2D as-built plans integrated with GIS databases for information management. The feasibility of incorporating 3D BIM models of the subsurface to replace the 2D plans to improve visualization and data management is examined in this paper. Obtaining an accurate image of the underground infrastructure would help minimize excavation accidents due to equipment-utility collisions and prevent property damage. Further, the inclusion of automated data collection and sharing features realized through BIM technology can enhance operations of smart cities. The research methodology consists of a state-of-the-art review of the current underground utility management systems, combined with statistical analysis of survey responses received from utility providers and one-call centers in the U.S. Three categories of utility practices are identified based on the level of digital technology integration. It is found that a vast majority of utility firms have adopted GIS databases with 2D plans, depth and other asset information, while a smaller percentage of providers have achieved full GIS-BIM integration, incorporating a wide range of asset data. Future progress on broader implementation appears to be constrained by the digital literacy of personnel and high costs of technology acquisition and application. A three-step framework for converting 2D plans to 3D BIM models is also presented and discussed. The process model proposed for this purpose allows the utilization of commercially available software with minimal need for additional coding.

3D face recognition:A comprehensive survey in 2022

In the past ten years,research on face recognition has shifted to using 3D facial surfaces,as 3D geometric information provides more discriminative features.This comprehensive survey reviews 3D face recognition techniques developed in the past decade,both conventional methods and deep learning methods.These methods are evaluated with detailed descriptions of selected representative works.Their advantages and disadvantages are summarized in terms of accuracy,complexity,and robustness to facial variations(expression,pose,occlusion,etc.).A review of 3D face databases is also provided,and a discussion of future research challenges and directions of the topic.

Modelling and mapping third dimension in a spatial database

In this paper,an overview of phases for modelling and mapping third dimension of spatial objects in a database is presented based on a selected spatial database management system(DBMS).These phases include(1)defining a spatial reference system for representing three-dimensional(3D)objects with real-world coordinates,(2)geometric modelling of 3D objects in the database,(3)3D spatial indexing for fast accessing/querying the 3D data,3D spatial queries and representation of 3D data.Then,a case study is performed to assess needs,possibilities and potential limitations of 3D data modelling in the spatial database.

基于C/S模式的女子体型识别及应用

采用C/S模式,建立女子体型的识别和应用系统。目的在于经过对三维人体数据的研究,生成符合人体尺寸的服装样板,应用于服装企业的生产中,以满足消费者的个性化需求。首先,通过三维人体扫描仪,采集江浙青年女子人体数据,构建人体数据库;再次,根据企业的服装款式,建立基本的样板数据库;最后,利用BP神经网络对个体特征参数进行识别分类,形成个性的服装样板图。这一系统通过VB.NET平台的自制软件得以实现,企业试用效果良好。