多层次三维地籍产权体模型的语义表达研究

针对我国不动产传统登记中的二维表达、房地分离的管理模式,在综合分析产权体的定义基础上,提出三维地籍产权体的定义和对象类型,并从概念层次引入一种基于语义的多层次三维地籍产权体模型。该模型能综合考虑土地和房产管理模式,将产权体划分为街坊、三维宗地、三维地籍物、分层空间与单元空间5个空间管理细节层次,探讨根据产权体的权属情况划分产权体层次的过程,并通过语义详细描述每个层次产权体的空间关系、权属关系和几何实体拓扑关系。基于以上的理论和方法,选取了某片区地籍数据作为试验数据,实现了多层次三维地籍产权体模型的语义表达,从而明晰了不动产产权三维登记,为"房地合一"地籍管理模式进一步深化了技术基础。     

三维地籍电子产权证的设计与实现

随着土地从粗放型向着集约化发展,三维地籍的建立势在必行,与之配套的三维产权证,对于三维地籍产权登记不可或缺。文中清晰阐述了三维地籍产权登记对象即三维产权体的概念;以传统房地产证为例分析了二维地籍产权证的设计现状,进而归纳得到地籍产权证的设计目的,并进一步提出三维地籍产权证的设计原则;遵从以上原则具体阐述三维产权证的内容,设计一种C/S架构制作和B/S架构发布相结合的三维地籍电子产权证,并以深圳市几宗三维产权体为实例给予具体构建。     

顾及外拓扑的产权体构建及其3-组合图表达

为构建和表达顾及外拓扑的产权体,以现有楼层平面图为基础,采用"推拉"二维图形的方式生成产权体三维模型,并使用3-组合图表达产权体的内拓扑与外拓扑,提出基于带权关联图与关联矩阵的"推拉"间隔传递方法,基于老新间隔对照关系的组合图飞镖生成方法以及组合图β关系的添加算法。通过"推拉"平面图的方式可以生成产权体三维模型;3-组合图可以表达产权体的内拓扑和外拓扑,并能提高构体效率。     

基于ArcEngine的三维地籍原型系统

为实现土地空间权利的登记和三维空间权属的管理,在三维地籍模型中引入三维地籍基本单元产权体的基础上,采用二维宗地与三维建筑物相结合的方法,依据现行的土地产权制度对三维产权进行了登记。以某小区三维建筑物为研究对象,构建了小区三维地籍数据库;并在.NET开发环境下,结合ArcGIS、ArcGIS Engine等技术开发了三维地籍原型系统。     

空间体对象间三维拓扑构建研究

根据三维拓扑的研究现状以及特定应用领域对三维拓扑的需求,分析了这些特定应用领域的拓扑关系,提出了两种三维拓扑构建方法。这两种方法在兼顾内拓扑的同时主要构建体之间的外拓扑关系。第一种方法是在体单独构建完毕后建立体之间的拓扑关系;第二种方法考虑到当前成熟三维建模软件或CAD软件中的数据大多以离散面方式组织,设计了自动寻体算法,同时构建体之间的外拓扑关系。利用深圳典型地籍数据和建筑设计图生成的三维数据进行实验,验证了此算法的可行性。     

三维地籍建模方法研究与实现

传统的地籍管理是以地表权利为核心的,不能满足地上或地下空间利用权利登记和管理的需求。因此,迫切的需要引入三维地籍来解决这些问题。本文分析了国内外三维地籍的研究现状,从技术角度入手,提出了面向三维地籍产权体的模型。基于该模型,建立了三维地籍系统,实现了诸如产权体的可视化、查询等功能。结果表明,该模型对三维地籍建模具有一定的参考价值和指导意义。     

三维地籍测绘研究及其标准化探索

针对传统的基于二维地籍的土地管理模式不能很好地满足日趋紧张的城市空间管理需求的问题,本文首先分析三维地籍国内外发展现状,提出了基于三维地籍测绘解决土地立体化管理难点、痛点的技术路线,然后开展了三维地籍标准化探索,重点介绍《三维地籍产权体测绘技术规程》的编制过程和主要内容,并将研究路线及此标准应用到典型案例中,以证明该技术路线的可行性和标准的适用性。     

基于层面结构的地质块体拓扑关系的自动构建

在地质建模中,基于层面的地质块体结构模型的获取是其中最重要的环节之一,目前的构建方法仅关注地质块体的提取和算法效率的提高,忽略了对地质块体与其组成面片以及各地质块体之间拓扑关系的建立,为此,本文提出了一种新的构建方法,基本思路是：首先,利用边界线与曲面片的关系,提取方向边和方向三角形,其次,按照右手法则建立面片排序表,最后,按照一定的遍历规则获取每个面片的正体和负体。此方法不仅可以自动确定地质块体与地质曲面片的组成关系,还可间接分析地质块体之间的邻接关系,从而为三维地质体模型的建立以及三维地质体拓扑查询和分析奠定基础。     

混合三维地籍的确权及概念模型研究

随着土地利用的立体化趋势越来越明显,人们对土地的理解从二维变为三维,土地三维权利也逐步确立。以地表权利为核心的传统地籍已不能满足实际需求,有必要建立三维地籍。本文在简介了土地三维产权和三维地籍的基础上,根据我国经济、法律和技术方面的具体情况,分析了三维宗地的相关权利,并提出了适用于我国的混合三维地籍概念模型,并以建筑物为例,设计了三维地籍概念模型。     

基于庞卡莱代数边界理论的三维地籍TEN模型

针对空间权属单元排他性特征,本文对不规则四面体格网的拓扑关系进行有效性筛分,细化出9种有效拓扑关系并对其进行描述,同时,建立相应拓扑规则,完成TEN模型改进并应用于三维地籍建模。基于庞卡莱边界代数和理论,推演了空间权属单元的合并算法,使其聚合为多胞元复合体,用以模拟权属空间。通过分析,提出10个剖分规则,实现了TEN复合体的分割。在VC++开发环境下,对合并与剖分进行了编程实现。实验证明,改进后的地籍TEN模型具有拓扑关系精练、易于实现的优点,能有效构建真三维权属空间,不失为一种简单高效的三维地籍建模方法。     

基于OGRE的高精度三维城市建模技术分析

三维城市模型作为城市三维地理信息系统的重要组成部分,已广泛应用于城市规划、城市建设、建筑设计等领域。随着计算机图形学技术以及虚拟现实技术的不断发展,为快速、自动化生成高精度的三维城市模型提供了条件。本文基于OGRE引擎,阐述了三维城市建模技术的整体架构及关键技术,开发了自动化建模工具及三维可视化平台,实现了城市建筑自动建模及模型实时渲染显示。     

一种基于无人机序列图像的地形地貌三维快速重建方法

提出了一种基于无人机序列图像的地形地貌三维重建方法,该方法采用Harris特征点和SIFT特征向量来提取图像特征,实现图像配准;采用准透视投影模型和因子化方法对未标定的图像序列进行自动标定;通过高效次优解三角化方法获取三维点云坐标;通过准稠密化扩散算法对三维点云进行稠密化;采用捆绑调整算法提高了空间三维点云的精度;采用Possion表面重建方法对三维点云进行了网格化处理.本文为无人机序列图像的应用提供了一个新的思路,拓展了无人机的应用空间.     

SURF算法在无人机倾斜摄影测量三维建模中的应用

针对无人机倾斜摄影测量影像的特点,采用一种影像特征点自动提取匹配算法,解决影像之间的比例尺不一致、分辨率不一致等问题,实现影像的自动精确匹配,最终构建具有精确地理信息的三维模型。实验结果表明构建的三维模型满足数字城市建设的需求,可为城市基础设施建设提供一种科学可靠的依据。     

Construction of 3D Volumetric Objects for a 3D Cadastral System

This article presents a new method to illustrate the feasibility of 3D topology creation. We base the 3D construction process on testing real cases of implementation of 3D parcels construction in a 3D cadastral system. With the utilization and development of dense urban space, true 3D geometric volume primitives are needed to represent 3D parcels with the adjacency and incidence relationship. We present an effective straightforward approach to identifying and constructing the valid volumetric cadastral object from the given faces, and build the topological relationships among 3D cadastral objects on‐the‐fly, based on input consisting of loose boundary 3D faces made by surveyors. This is drastically different from most existing methods, which focus on the validation of single volumetric objects after the assumption of the object's creation. Existing methods do not support the needed types of geometry/topology (e.g. non 2‐manifold, singularities) and how to create and maintain valid 3D parcels is still a challenge in practice. We will show that the method does not change the faces themselves and faces in a given input are independently specified. Various volumetric objects, including non‐manifold 3D cadastral objects (legal spaces), can be constructed correctly by this method, as will be shown from the results.     

三维几何体的验证规则及修复方法研究

为满足三维应用的需要,人们开始关注真三维几何体的创建来支撑现实世界中的各种三维对象,这些三维对象可能是一般三维体,也可能是非流形的三维几何体。给出了一种满足现实世界对象要求的三维几何体定义,详细分析了这种三维几何体所需要满足的各种规则,进而结合实例给出了相应的验证方法,同时就三维建模时三维几何体数据的修复问题进行了讨论。     

基于ArcEngine小区三维排水管网验收系统设计与实现

分析了小区地下排水管网的设计、建设、验收的自动检测系统的必要性,介绍了利用ArcEngine开发GIS软件的优点,实现了小区地下排水管网的三维建模及其自动检测系统,即小区三维排水管网的验收系统;重点讨论了地下排水管网的三维建模方法,解决了以往三维场景中的三维模型只能显示、不能查询编辑的问题。     

GIS中三维模型的设计

研究了三维GIS中的空间信息传输模式 ,探讨了平面地图符号与三维模型的区别与联系 ,阐述了三维模型的确立、定位、简化描述和逻辑性设计     

Automatic 3D modelling of metal frame connections from LiDAR data for structural engineering purposes

The automatic generation of 3D as-built models from LiDAR data is a topic where significant progress has been made in recent years. This paper describes a new method for the detection and automatic 3D modelling of frame connections and the formation of profiles comprising a metal frame from LiDAR data. The method has been developed using an approach to create 2.5D density images for subsequent processing using the Hough transform. The structure connections can be automatically identified after selecting areas in the point cloud. As a result, the coordinates of the connection centre, composition (profiles, size and shape of the haunch) and direction of their profiles are extracted. A standard file is generated with the data obtained from the geometric and semantic characterisation of the connections. The 3D model of connections and metal frames, which are suitable for processing software for structural engineering applications, are generated automatically based on this file. The algorithm presented in this paper has been tested under laboratory conditions and also with several industrial portal frames, achieving promising results. Finally, 3D models were generated, and structural calculations were performed.     

Automatic reasoning for geometric constraints in 3D city models with uncertain observations

This paper presents a novel approach to automated geometric reasoning for 3D building models. Geometric constraints like orthogonality or parallelity play a prominent role in man-made objects such as buildings. Thus, constraint based modelling, that specifies buildings by their individual components and the constraints between them, is a common approach in 3D city models. Since prototyped building models allow one to incorporate a priori knowledge they support the 3D reconstruction of buildings from point clouds and allow the construction of virtual cities. However, high level building models have a high degree of complexity and consequently are not easily manageable. Interactive tools are needed which facilitate the development of consistent models that, for instance, do not entail internal logical contradictions. Furthermore, there is often an interest in a compact, redundancy-free representation. We propose an approach that uses algebraic methods to prove that a constraint is deducible from a set of premises. While automated reasoning in 2D models is practical, a substantial increase in complexity can be observed in the transition to the three-dimensional space. Apart from that, algebraic theorem provers are restricted to crisp constraints so far. Thus, they are unable to handle quality issues, which are, however, an important aspect of GIS data and models. In this article we present an approach to automatic 3D reasoning which explicitly addresses uncertainty. Hereby, our aim is to support the interactive modelling of 3D city models and the automatic reconstruction of buildings. Geometric constraints are represented by multivariate polynomials whereas algebraic reasoning is based on Wu’s method of pseudodivision and characteristic sets. The reasoning process is further supported by logical inference rules. In order to cope with uncertainty and to address quality issues the reasoner integrates uncertain projective geometry and statistical hypothesis tests. Consequently, it allows one to derive uncertain conclusions from uncertain premises. The quality of such conclusions is quantified in a way which is sound both from a logical and a statistical perspective.     

面向数字城市建设的三维建模关键技术研究与应用

三维模型数据以其直观性、客观性和真实性等特性,成为数字城市数据库中的重要组成部分。为了解决三维模型数据获取的精准性和高效性等,在建设数字城市过程中,采取多种技术方式实现三维模型的获取。包括采用传统手工三维建模实现三维精细模型的精准性,采用三维激光扫描技术实现三维模型数据的超精细化,以倾斜摄影测量的半自动建模方式实现快速建模等。本文从技术角度全面总结了在建设数字城市过程中三维模型的具体技术途径及应用方式。三维模型数据应用于数字城市的历史文保、教育、经济等多个领域,为智慧城市的建设奠定了坚实的数据基础。