A Semantic-Sensitive Approach to Indoor and Outdoor 3D Data Organization

Building model data organization is often programmed to solve a specific problem,resulting in the inability to organize indoor and outdoor 3D scenes in an integrated manner.In this paper,existing building spatial data models are studied,and the characteristics of building information modeling standards(IFC),city geographic modeling language(CityGML),indoor modeling language(IndoorGML),and other models are compared and analyzed.CityGML and IndoorGML models face challenges in satisfying diverse application scenarios and requirements due to limitations in their expression capabilities.It is proposed to combine the semantic information of the model objects to effectively partition and organize the indoor and outdoor spatial 3D model data and to construct the indoor and outdoor data organization mechanism of“chunk-layer-subobject-entrances-area-detail object.”This method is verified by proposing a 3D data organization method for indoor and outdoor space and constructing a 3D visualization system based on it.

Indoor Space Modeling and Parametric Component Construction Based on 3D Laser Point Cloud Data

In order to enhance modeling efficiency and accuracy,we utilized 3D laser point cloud data for indoor space modeling.Point cloud data was obtained with a 3D laser scanner and optimized with Autodesk Recap and Revit software to extract geometric information about the indoor environment.Furthermore,we proposed a method for constructing indoor elements based on parametric components.The research outcomes of this paper will offer new methods and tools for indoor space modeling and design.The approach of indoor space modeling based on 3D laser point cloud data and parametric component construction can enhance modeling efficiency and accuracy,providing architects,interior designers,and decorators with a better working platform and design reference.

Fabrication of polyetheretherketone(PEEK)-based 3D electronics with fine resolution by a hydrophobic treatment assisted hybrid additive manufacturing method

Additive manufacturing(AM)is a free-form technology that shows great potential in the integrated creation of three-dimensional(3D)electronics.However,the fabrication of 3D conformal circuits that fulfill the requirements of high service temperature,high conductivity and high resolution remains a challenge.In this paper,a hybrid AM method combining the fused deposition modeling(FDM)and hydrophobic treatment assisted laser activation metallization(LAM)was proposed for manufacturing the polyetheretherketone(PEEK)-based 3D electronics,by which the conformal copper patterns were deposited on the 3D-printed PEEK parts,and the adhesion between them reached the 5B high level.Moreover,the 3D components could support the thermal cycling test from-55℃ to 125℃ for more than 100 cycles.Particularly,the application of a hydrophobic coating on the FDM-printed PEEK before LAM can promote an ideal catalytic selectivity on its surface,not affected by the inevitable printing borders and pores in the FDM-printed parts,then making the resolution of the electroless plated copper lines improved significantly.In consequence,Cu lines with width and spacing of only60μm and 100μm were obtained on both as-printed and after-polished PEEK substrates.Finally,the potential of this technique to fabricate 3D conformal electronics was demonstrated.

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.

A novel method for virtual clearance computation of high-speed train based on model integration and convex hull

The 3D clearance of a high-speed train(HST) is critical to ensure the safety of railway transportation. Many studies have been conducted on the inspection of the clearance profile in railway operation based on the vision system, but few researchers have focused on the computation of the 3D clearance in the design phase of an HST. This paper summarizes the virtual 3D clearance computation of an HST based on model integration and the convex hull method. First, both the aerodynamic and kinetic analysis models of the HST are constructed. The two models are then integrated according to the corresponding relationship map, and an array of transformation matrixes of the HST is created to drive the designed model simulating the physical railway motion. Furthermore, the convex hull method is adopted to compute the 3D envelope of the moving train. Finally, the Hausdorff metric is involved in the measurement of the minimum clearance model and the 3D envelope model. In addition, the color map of the Hausdorff distance is established to verify that the designed shape of the HST meets the national standards. This paper provides an effective method to accurately calculate the 3D clearance for the shape design of an HST, which greatly reduces the development cost by minimizing the physical prototype that must be built.

Application of 3D CAD Modeling in Designing 330 kV Outdoor Switch Yard Layout

The Development of 3D CAD technology presents a new effective tool in designing outdoor switch yard for power plant. A new layout pattern of 330 kV switch yard (SWYD) of aligned type was studied with this method. Some issues about computerized 3D modes applied in SWYD design are also discussed in this paper.

Coping with uncertainties through an automated workflow for 3D reservoir modelling of carbonate reservoirs

Reliable 3D modelling of underground hydrocarbon reservoirs is a challenging task due to the complexity of the underground geological formations and to the availability of different types of data that are typically affected by uncertainties. In the case of geologically complex depositional environments, such as fractured hydrocarbon reservoirs, the uncertainties involved in the modelling process demand accurate analysis and quantification in order to provide a reliable confidence range of volumetric estimations. In the present work, we used a 3D model of a fractured carbonate reservoir and populated it with different lithological and petrophysical properties. The available dataset also included a discrete fracture network(DFN) property that was used to model the fracture distribution. Uncertainties affecting lithological facies, their geometry and absolute positions(related to the fault system), fracture distribution and petrophysical properties were accounted for. We included all different types of uncertainties in an automated approach using tools available in today’s modelling software packages and combining all the uncertain input parameters in a series of statistically representative geological realizations. In particular, we defined a specific workflow for the definition of the absolute permeability according to an equivalent, single porosity approach, taking into account the contribution of both the matrix and the fracture system. The results of the analyses were transferred into a 3D numerical fluid-dynamic simulator to evaluate the propagation of the uncertainties associated to the input data down to the final results, and to assess the dynamic response of the reservoir following a selected development plan. The "integrated approach" presented in this paper can be useful for all technicians involved in the construction and validation of 3D numerical models of hydrocarbon-bearing reservoirs and can potentially become part of the educational training for young geoscientists and engineers, since an integrated and well-constructed workflow is the backbone of any reservoir study.

Metallogenic model of the Shuangjianzishan Ag-Pb-Zn district,Northeast China:Revealed from integrated geophysical investigation

The Shuangjianzishan deposit in Inner Mongolia is a typical Ag-Pb-Zn deposit of the southern Great Xing’an Range.Proven reserves of Ag,Pb,and Zn in this deposit have reached the scale of super-large deposits,with favorable metallogenic conditions,strong prospecting signs,and high metallogenic potential.This paper reports a study involving integrated geophysical methods,including controlled-source audio-frequency magnetotelluric,gravity,magnetic,and shallow-seismic-reflection methods,to determine the spatial distribution of ore-controlling structures and subsurface intrusive rock for a depth range of<2000 m in the Shuangjianzishan ore district.The objective of this study is to construct a metallogenic model of the ore district and provide a scientific basis for the exploration of similar deposits in the deep and surrounding regions.We used three-dimensional inversion for controlled-source audio-frequency magnetotelluric data based on the limited memory quasi-Newton algorithm,and three-dimensional physical-property inversion for the gravity and magnetic data to obtain information about the subsurface distribution of ore-controlling structures and intrusive rocks.Under seismic reflection results,regional geology,petrophysical properties,and borehole information,the geophysical investigation shows that the Dashizhai group,which contains the main ore-bearing strata in the ore district,is distributed within a depth range of<1239 m,and is thick in the Xinglongshan ore block and the eastern part of the Shuangjianzishan ore block.The mineralization is spatially associated with a fault system characterized by NE-,NW-,and N-trending faults.The magnetic and electrical models identify large,deep bodies of intrusive rock that are inferred to have been involved in mineralization,with local shallow emplacement of some intrusions.Combining the subsurface spatial distributions of ore-bearing strata,ore-controlling faults,and intrusive rock,we propose two different metallogenic models for the Shuangjianzishan ore district,which provide a scientific basis for further prospecting in the deep regions of the ore district and surrounding areas.

Perspectives on point cloud-based 3D scene modeling and XR presentation within the cloud-edge-client architecture

With the support of edge computing,the synergy and collaboration among central cloud,edge cloud,and terminal devices form an integrated computing ecosystem known as the cloud-edge-client architecture.This integration unlocks the value of data and computational power,presenting significant opportunities for large-scale 3D scene modeling and XR presentation.In this paper,we explore the perspectives and highlight new challenges in 3D scene modeling and XR presentation based on point cloud within the cloud-edge-client integrated architecture.We also propose a novel cloud-edge-client integrated technology framework and a demonstration of municipal governance application to address these challenges.

A unified 3D space-based navigation model for seamless navigation in indoor and outdoor

Seamless navigation has attracted lots of attention and many methods have been reported in the literature or made available as commercial applications.The process of navigation can be interpreted as a continuous movement of 3D objects from one unoccupied 3D indoor/outdoor space to another.From a technical perspective,a 3D navigation model is one of the critical components that should be available to perform successful navigation.A major approach to build a unified navigation model to support seamless path computation is linking indoor navigation networks to outdoor road/street-based networks.Because of different sources of indoor and outdoor navigation networks,the major approach fails to build up true seamless navigation models.With regards to this,we propose a unified 3D space-based navigation model(U3DSNM).The presented model ensures all types of spaces for navigation(indoor,semi-indoor,semi-outdoor,and outdoor)have the same representation,management methods,and network derivation approach,thereby building up unified navigation networks to support seamless navigation paths planning.The model can be linked to the international standards(data models)that are also based on spaces,such as IndoorGML and the on-going version of CityGML 3.0.Three navigation path planning cases show the feasibility of U3DSNM.

基于数字孪生的室内外一体化建模仿真研究与验证

面对日趋复杂的网络架构,数字孪生技术将成为精准预测网络性能的有效手段之一。本文提出了一种基于数字孪生的室内外一体化建模仿真方法,通过结合使用建筑信息模型和地理信息系统技术,将室内外环境融合并实现场景孪生,萃取出无线信道特性并完成区域网络性能预测。最后通过将预测结果与实测结果进行对比,验证了基于数字孪生的室内外一体化建模方案对网络覆盖预测性能有显著提升作用。

室内外一体化三维建模技术探索与实现

针对建筑物室内外建模的不同特点及室内外一体化建模的需求,综合考虑建模效率、精度、成本等因素,开展了基于无人机倾斜摄影测量的大场景三维建模技术及基于设计图的区域室内建模技术探索,实现了无像控点的高精度室外三维模型快速构建,并基于SketchUp构建了具备动态交互效果的室内三维模型,打通了室内外三维建模技术流程,可为三维模型建设及相关应用提供技术参考。

基于3DS MAX的校园三维模型室内外一体化制作

研究了基于3DS MAX软件的校园三维模型的制作步骤和方法,讨论了校区建模的数据采集、纹理生成、模型修改等关键技术;特别阐述了室内建模的制作方法和技巧,弥补了三维室内建模的空白。

基于3D建模和射线跟踪算法的5G室内深度覆盖预测方法研究

由于5G室内覆盖的方案设计过程中,有着较高的复杂性,同时也具有着多样性的特征,因此就使得在运行的过程中,5G室内覆盖的效果难以进行准确的预测。因此,在分析过程中,就着重针对3D建模以及射线跟踪算法下,对其5G舍内深度覆盖进行预测方法的分析和研究,以此帮助相关领域的工作人员进行研究。

倾斜三维实景模型与BIM模型融合的室内外一体化场景构建

倾斜三维实景模型以其高空间精度、高分辨率、真纹理的优势在各行各业尤其是数字城市的建设中应用广泛;BIM技术包含丰富的建筑信息,是建筑管理功能的集大成者。本文基于倾斜摄影测量技术,采用飞马D2000无人机获取测区影像并构建三维实景模型,采用飞马SLAM100手持激光扫描仪获取目标建筑的室内点云数据,并结合BIM技术构建室内BIM模型,选用易智瑞GeoScene Pro平台,实现模型的融合及室内外一体化场景的创建、模型属性查询及管理分析应用,以期为实景三维建设的相关应用提供借鉴。

3D integrated modeling approach to geo-engineering objects of hydraulic and hydroelectric projects

Aiming at 3D modeling and analyzing problems of hydraulic and hydroelectric en-gineering geology,a complete scheme of solution is presented. The first basis was NURBS-TIN-BRep hybrid data structure. Then,according to the classified thought of the object-oriented technique,the different 3D models of geological and engi-neering objects were realized based on the data structure,including terrain class,strata class,fault class,and limit class;and the modeling mechanism was alterna-tive. Finally,the 3D integrated model was established by Boolean operations be-tween 3D geological objects and engineering objects. On the basis of the 3D model,a series of applied analysis techniques of hydraulic and hydroelectric engineering geology were illustrated. They include the visual modeling of rock-mass quality classification,the arbitrary slicing analysis of the 3D model,the geological analysis of the dam,and underground engineering. They provide powerful theoretical prin-ciples and technical measures for analyzing the geological problems encountered in hydraulic and hydroelectric engineering under complex geological conditions.

室内外一体化的三维GIS原型系统设计与开发

目前,在全球卫星系统、立体视觉技术的支持下,室外场景三维地图的漫游导航功能已高度完善,对于卫星无法覆盖但场景更加复杂的室内场景,其三维地图的绘制和路径规划等功能的实现则相对落后,无法满足用户室内寻址的要求。因此,构建室内三维地图并与室外地图结合实现市内外一体的三维GIS系统具有重要意义。论文以南京邮电大学校园为实验区域,基于Skyline平台提供的二次开发接口,应用Web GIS技术设计并开发了室内外一体的三维GIS原型系统。该系统中,基于遥感图像、CAD数据和相关属性数据,建立了校园建筑三维模型,并构建了室外和室内一体的三维校园,实现了直观的室内外三维漫游,同时具备了三维测量和分析、室内外一体化路径规划等功能,能够使用户快速熟悉校园空间信息,为用户提供沉浸式的体验。

3D indoor scene modeling from RGB-D data:a survey

3D scene modeling has long been a fundamental problem in computer graphics and computer vision. With the popularity of consumer-level RGB-D cameras,there is a growing interest in digitizing real-world indoor 3D scenes. However,modeling indoor3 D scenes remains a challenging problem because of the complex structure of interior objects and poor quality of RGB-D data acquired by consumer-level sensors.Various methods have been proposed to tackle these challenges. In this survey,we provide an overview of recent advances in indoor scene modeling techniques,as well as public datasets and code libraries which can facilitate experiments and evaluation.

基于变电站机房室内外一体的建模技术研究

变电站机房是一项重要的国家基础设施。变电站机房维护管理部门需要对变电站机房进行周期性的电力巡检以防止和杜绝安全事故的发生。在多视图立体几何匹配的技术支撑下,获取高精度、高完整度的变电站机房室内外一体的三维模型能够为电力巡检、调度维护提供更全面的监测数据和解决方案。该文分析建模中的关键技术,并通过摄像机采集的变电站机房视频、图像数据进行实景三维重建,研究多视图重建在电力巡检与调度指挥方面的相关技术实现和应用研究,并采用主流算法软件平台实现变电站机房室内外一体的真实场景模型的重建及展示。

基于单轨道InSAR的矿区地表三维形变监测研究

【目的】基于单轨道InSAR进行长时序地表三维形变监测,解决时空失相干问题,分析总结研究区域的沉降规律。【方法】采用时序D-InSAR和概率积分模型融合方法对红庆河煤矿的长时序地表形变进行监测,获取地表三维形变进行分析。【结果】融合方法解算的三维形变与实测数据较为一致,融合方法垂直向、东西向及南北向的精度分别为0.100 m、0.018 m、0.025 m。【结论】大梯度形变引起的失相干引起问题得到解决,融合方法对三维形变的监测精度均有提高;红庆河煤矿沉降影响范围沿工作面开采方向减小;东西、南北向形变在工作面呈对称分布。