INTEGRATION BETWEEN SURFACE AND SUBSURFACE SPATIAL OBJECTS FOR DEVELOPING OMAN 3D SDI BASED ON THE CITYGML STANDARD

Abstract. The paper investigates the capability to integrate the surface and subsurface 3D spatial objects data structure within the 3D spatial data infrastructure (3D SDI) based on the CityGML standards. In fact, a number of countries around the world have started applying the 3D city models for their planning and infrastructure management. While others are still working toward 3D SDI by using CityGML standards. Moreover, most of these initiatives focus on the surface spatial objects with less interest to model subsurface spatial objects. However, dealing with 3D SDI requires both surface and subsurface spatial objects with clear consideration on the issues and challenges in terms of the data structure. On the other hand, the study has used geospatial tools and databases such as FME, PostgreSQL-PostGIS, and 3D City Database to generate the 3D model and to test the capability for integrating the surface and subsurface 3D spatial objects data structure within the 3D SDI. This paper concludes by describing a framework that aims to integrate surface and subsurface 3D geospatial objects data structure in Oman SDI. The authors believe that there are possible solutions based on CityGML standards for surface and subsurface 3D spatial objects. Moreover, solving the issues in data structure can establish a better vision and open new avenues for the 3D SDI.

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Services Oriented Smart City Platform Based On 3d City Model Visualization

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsannals-ii-4-59-2014 ◽

2014 ◽

Vol II-4 ◽

pp. 59-64 ◽

Cited By ~ 8

Author(s):

F. Prandi ◽

M. Soave ◽

F. Devigili ◽

M. Andreolli ◽

R. De Amicis

Keyword(s):

Spatial Data ◽

Smart City ◽

Smart Cities ◽

Geographical Information ◽

Data Infrastructure ◽

3D City Models ◽

3D City Model ◽

Key Factor ◽

City Model ◽

City Models

The rapid technological evolution, which is characterizing all the disciplines involved within the wide concept of smart cities, is becoming a key factor to trigger true user-driven innovation. However to fully develop the Smart City concept to a wide geographical target, it is required an infrastructure that allows the integration of heterogeneous geographical information and sensor networks into a common technological ground. In this context 3D city models will play an increasingly important role in our daily lives and become an essential part of the modern city information infrastructure (Spatial Data Infrastructure). The work presented in this paper describes an innovative Services Oriented Architecture software platform aimed at providing smartcities services on top of 3D urban models. 3D city models are the basis of many applications and can became the platform for integrating city information within the Smart-Cites context. In particular the paper will investigate how the efficient visualisation of 3D city models using different levels of detail (LODs) is one of the pivotal technological challenge to support Smart-Cities applications. The goal is to provide to the final user realistic and abstract 3D representations of the urban environment and the possibility to interact with a massive amounts of semantic information contained into the geospatial 3D city model. The proposed solution, using OCG standards and a custom service to provide 3D city models, lets the users to consume the services and interact with the 3D model via Web in a more effective way.

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GENERATING, STORING, UPDATING AND DISSEMINATING A COUNTRYWIDE 3D MODEL

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xliv-4-w1-2020-27-2020 ◽

2020 ◽

Vol XLIV-4/W1-2020 ◽

pp. 27-32

Author(s):

B. Dukai ◽

R. Peters ◽

T. Wu ◽

T. Commandeur ◽

H. Ledoux ◽

...

Keyword(s):

Data Structure ◽

The Netherlands ◽

3D Model ◽

Large Cities ◽

3D City Models ◽

3D City Model ◽

3D Data ◽

City Model ◽

Structure Height ◽

City Models

Abstract. As in many countries, in The Netherlands governmental organisations are acquiring 3D city models to support their public tasks. However, this is still being done within individual organisation, resulting in differences in 3D city models within one country and sometimes covering the same area: i.e. differences in data structure, height references used, update cycle, data quality, use of the 3D data etc. In addition, often only large governmental organisations can afford investing in 3D city models (and the required knowledge) and not small organisations, like small municipalities. To address this problem, the Dutch Kadaster is collaborating with the 3D Geoinformation research group at TU Delft to generate and disseminate a 3D city model covering the whole of the Netherlands and to do this in a sustainable manner, i.e. with an implementation that ensures periodical updates and that aligns with the 3D city models of other governmental organisations, such as large cities. This article describes the workflow that has been developed and implemented.

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Incorporating Topological Representation in 3D City Models

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi8080347 ◽

2019 ◽

Vol 8 (8) ◽

pp. 347 ◽

Cited By ~ 5

Author(s):

Stelios Vitalis ◽

Ken Ohori ◽

Jantien Stoter

Keyword(s):

Data Structure ◽

Data Model ◽

Semantic Information ◽

Semantic Representation ◽

Geometric Analysis ◽

Computationally Efficient ◽

Real World Data ◽

3D City Models ◽

Map Data ◽

City Models

3D city models are being extensively used in applications such as evacuation scenarios and energy consumption estimation. The main standard for 3D city models is the CityGML data model which can be encoded through the CityJSON data format. CityGML and CityJSON use polygonal modelling in order to represent geometries. True topological data structures have proven to be more computationally efficient for geometric analysis compared to polygonal modelling. In a previous study, we have introduced a method to topologically reconstruct CityGML models while maintaining the semantic information of the dataset, based solely on the combinatorial map (C-Map) data structure. As a result of the limitations of C-Map’s semantic representation mechanism, the resulting datasets could suffer either from semantic information loss or the redundant repetition of them. In this article, we propose a solution for a more efficient representation of geometry, topology and semantics by incorporating the C-Map data structure into the CityGML data model and implementing a CityJSON extension to encode the C-Map data. In addition, we provide an algorithm for the topological reconstruction of CityJSON datasets to append them according to this extension. Finally, we apply our methodology to three open datasets in order to validate our approach when applied to real-world data. Our results show that the proposed CityJSON extension can represent all geometric information of a city model in a lossless way, providing additional topological information for the objects of the model.

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On the Reliable Generation of 3D City Models from Open Data

Urban Science ◽

10.3390/urbansci4040047 ◽

2020 ◽

Vol 4 (4) ◽

pp. 47

Author(s):

Renoy Girindran ◽

Doreen S Boyd ◽

Julian Rosser ◽

Dhanya Vijayan ◽

Gavin Long ◽

...

Keyword(s):

High Resolution ◽

Open Source ◽

3D Model ◽

Airborne Lidar ◽

Data Availability ◽

Small Subset ◽

Surface Model ◽

High Resolution Data ◽

3D City Models ◽

City Models

A 3D model communicates more effectively than a 2D model, hence the applications of 3D city models are rapidly gaining significance in urban studies. However, presently, there is a dearth of free of cost, high-resolution 3D city models available for use. This paper offers potential solutions to this problem by providing a globally replicable methodology to generate low-cost 3D city models from open source 2D building data in conjunction with open satellite-based elevation datasets. Two geographically and morphologically different case studies were used to develop and test this methodology: the Chinese city of Shanghai and the city of Nottingham in the UK. The method is based principally on OpenStreetMap (OSM) and Advanced Land Observing Satellite World 3D digital surface model (AW3D DSM) data and use GMTED 2010 DTM data for undulating terrain. Further enhancement of the resultant 3D model, though not compulsory, uses higher resolution elevation models that are not always open source, but if available can be used (i.e., airborne LiDAR generated DTM). Further we test and develop methods to improve the accuracy of the generated 3D models, employing a small subset of high resolution data that are not open source but can be purchased with a minimal budgets. Given these scenarios of data availability are globally applicable and time-efficient for 3D building generation (where 2D building footprints are available), our proposed methodology has the potential to accelerate the production of 3D city models, and thus to facilitate their dependent applications (e.g., disaster management) wherever commercial 3D city models are unavailable.

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A Method for the Automated Construction of 3D Models of Cities and Neighborhoods from Official Cadaster Data for Solar Analysis

Sustainability ◽

10.3390/su13116028 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6028

Author(s):

Carlos Beltran-Velamazan ◽

Marta Monzón-Chavarrías ◽

Belinda López-Mesa

Keyword(s):

3D Model ◽

3D Models ◽

Automatic Method ◽

Time Saving ◽

Automatic Construction ◽

3D City Models ◽

Solar Analysis ◽

Solar Access ◽

Short Time ◽

City Models

3D city models are a useful tool to analyze the solar potential of neighborhoods and cities. These models are built from buildings footprints and elevation measurements. Footprints are widely available, but elevation datasets remain expensive and time-consuming to acquire. Our hypothesis is that the GIS cadastral data can be used to build a 3D model automatically, so that generating complete cities 3D models can be done in a short time with already available data. We propose a method for the automatic construction of 3D models of cities and neighborhoods from 2D cadastral data and study their usefulness for solar analysis by comparing the results with those from a hand-built model. The results show that the accuracy in evaluating solar access on pedestrian areas and solar potential on rooftops with the automatic method is close to that from the hand-built model with slight differences of 3.4% and 2.2%, respectively. On the other hand, time saving with the automatic models is significant. A neighborhood of 400,000 m2 can be built up in 30 min, 50 times faster than by hand, and an entire city of 967 km2 can be built in 8.5 h.

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A PROPOSAL FOR GENERALIZATION OF 3D MODELS

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-iv-4-w4-389-2017 ◽

2017 ◽

Vol IV-4/W4 ◽

pp. 389-392 ◽

Cited By ~ 1

Author(s):

A. Uyar ◽

N. N. Ulugtekin

Keyword(s):

Data Model ◽

3D Model ◽

Open Data ◽

3D Models ◽

3D Modelling ◽

3D City Models ◽

Model Generalization ◽

Level Of Details ◽

Future Work ◽

City Models

In recent years, 3D models have been created of many cities around the world. Most of the 3D city models have been introduced as completely graphic or geometric models, and the semantic and topographic aspects of the models have been neglected. In order to use 3D city models beyond the task, a generalization is necessary. CityGML is an open data model and XML-based format for the storage and exchange of virtual 3D city models. Level of Details (LoD) which is an important concept for 3D modelling, can be defined as outlined degree or prior representation of real-world objects. The paper aim is first describes some requirements of 3D model generalization, then presents problems and approaches that have been developed in recent years. In conclude the paper will be a summary and outlook on problems and future work.

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Spatial ETL for 3D Building Modelling Based on Unmanned Aerial Vehicle Data in Semi-Urban Areas

Remote Sensing ◽

10.3390/rs12121972 ◽

2020 ◽

Vol 12 (12) ◽

pp. 1972 ◽

Cited By ~ 1

Author(s):

Urška Drešček ◽

Mojca Kosmatin Fras ◽

Jernej Tekavec ◽

Anka Lisec

Keyword(s):

Unmanned Aerial Vehicle ◽

Spatial Data ◽

Urban Areas ◽

Point Cloud ◽

Process Model ◽

Laser Scanning ◽

3D City Models ◽

Aerial Vehicle ◽

Spatial Etl ◽

City Models

This paper provides the innovative approach of using a spatial extract, transform, load (ETL) solution for 3D building modelling, based on an unmanned aerial vehicle (UAV) photogrammetric point cloud. The main objective of the paper is to present the holistic workflow for 3D building modelling, emphasising the benefits of using spatial ETL solutions for this purpose. Namely, despite the increasing demands for 3D city models and their geospatial applications, the generation of 3D city models is still challenging in the geospatial domain. Advanced geospatial technologies provide various possibilities for the mass acquisition of geospatial data that is further used for 3D city modelling, but there is a huge difference in the cost and quality of input data. While aerial photogrammetry and airborne laser scanning involve high costs, UAV photogrammetry has brought new opportunities, including for small and medium-sized companies, by providing a more flexible and low-cost source of spatial data for 3D modelling. In our data-driven approach, we use a spatial ETL solution to reconstruct a 3D building model from a dense image matching point cloud which was obtained beforehand from UAV imagery. The results are 3D building models in a semantic vector format consistent with the OGC CityGML standard, Level of Detail 2 (LOD2). The approach has been tested on selected buildings in a simple semi-urban area. We conclude that spatial ETL solutions can be efficiently used for 3D building modelling from UAV data, where the data process model developed allows the developer to easily control and manipulate each processing step.

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3D Hilbert Space Filling Curves in 3D City Modeling for Faster Spatial Queries

International Journal of 3-D Information Modeling ◽

10.4018/ij3dim.2014040101 ◽

2014 ◽

Vol 3 (2) ◽

pp. 1-18

Author(s):

Uznir Ujang ◽

Francois Anton ◽

Suhaibah Azri ◽

Alias Abdul Rahman ◽

Darka Mioc

Keyword(s):

Spatial Data ◽

Nearest Neighbor ◽

Model Data ◽

Space Filling ◽

Space Filling Curves ◽

3D City Models ◽

3D City Model ◽

City Modeling ◽

City Model ◽

City Models

The advantages of three dimensional (3D) city models can be seen in various applications including photogrammetry, urban and regional planning, computer games, etc. They expand the visualization and analysis capabilities of Geographic Information Systems on cities, and they can be developed using web standards. However, these 3D city models consume much more storage compared to two dimensional (2 D) spatial data. They involve extra geometrical and topological information together with semantic data. Without a proper spatial data clustering method and its corresponding spatial data access method, retrieving portions of and especially searching these 3D city models, will not be done optimally. Even though current developments are based on an open data model allotted by the Open Geospatial Consortium (OGC) called CityGML, its XML-based structure makes it challenging to cluster the 3D urban objects. In this research, the authors propose an opponent data constellation technique of space-filling curves (3D Hilbert curves) for 3D city model data representation. Unlike previous methods, that try to project 3D or n-dimensional data down to 2D or 3D using Principal Component Analysis (PCA) or Hilbert mappings, in this research, they extend the Hilbert space-filling curve to one higher dimension for 3D city model data implementations. The query performance was tested for single object, nearest neighbor and range search queries using a CityGML dataset of 1,000 building blocks and the results are presented in this paper. The advantages of implementing space-filling curves in 3D city modeling will improve data retrieval time by means of optimized 3D adjacency, nearest neighbor information and 3D indexing. The Hilbert mapping, which maps a sub-interval of the ([0,1]) interval to the corresponding portion of the d-dimensional Hilbert's curve, preserves the Lebesgue measure and is Lipschitz continuous. Depending on the applications, several alternatives are possible in order to cluster spatial data together in the third dimension compared to its clustering in 2 D.

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SPATIAL DATA SUPPLY CHAINS

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsarchives-xl-4-w7-41-2015 ◽

2015 ◽

Vol XL-4/W7 ◽

pp. 41-45 ◽

Cited By ~ 3

Author(s):

P. Varadharajulu ◽

M. Azeem Saqiq ◽

F. Yu ◽

D. A. McMeekin ◽

G. West ◽

...

Keyword(s):

Supply Chain ◽

New Zealand ◽

Supply Chains ◽

Spatial Data ◽

Paradigm Shift ◽

End User ◽

Consultation Process ◽

Data Infrastructure ◽

Manufacturing Supply Chain ◽

The World

This paper describes current research into the supply of spatial data to the end user in as close to real time as possible via the World Wide Web. The Spatial Data Infrastructure paradigm has been discussed since the early 1990s. The concept has evolved significantly since then but has almost always examined data from the perspective of the supplier. It has been a supplier driven focus rather than a user driven focus. The current research being conducted is making a paradigm shift and looking at the supply of spatial data as a supply chain, similar to a manufacturing supply chain in which users play a significant part. A comprehensive consultation process took place within Australia and New Zealand incorporating a large number of stakeholders. Three research projects that have arisen from this consultation process are examining Spatial Data Supply Chains within Australia and New Zealand and are discussed within this paper.

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A FRAMEWORK FOR THE REPRESENTATION OF TWO VERSIONS OF A 3D CITY MODEL IN 4D SPACE

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-iv-4-w6-81-2018 ◽

2018 ◽

Vol IV-4/W6 ◽

pp. 81-88 ◽

Cited By ~ 1

Author(s):

S. Vitalis ◽

K. Arroyo Ohori ◽

J. Stoter

Keyword(s):

Data Structure ◽

Conceptual Framework ◽

Urban Areas ◽

Level Of Detail ◽

3D City Models ◽

3D City Model ◽

Multiple Datasets ◽

City Model ◽

City Models ◽

Representation Of Time

Abstract. 3D city models are being increasingly adopted by organisations in order to serve application needs related to urban areas. In order to fulfil the different requirements of various applications, the concept of Level of Detail (LoD) has been incorporated in 3D city models specifications, such as CityGML. Therefore, datasets of different LoDs are being created for the same areas by several organisations for their own use cases. Meanwhile, as time progresses newer versions of existing 3D city models are being created by vendors. Nevertheless, the existing mechanisms for representating multi-LoD data has not been adopted by the users and there has been little effort on the implementation of a mechanism to store multiple revisions of a city model. This results in redundancy of information and the existence of multiple datasets inconsistent with each other. Alternatively, a representation of time or scale as additional dimensions to the three spatial ones has been proposed as a better way to store multiple versions of datasets while retaining information related to the corresponding features between datasets. In this paper, we propose a conceptual framework with initial considerations for the implementation of a 4D representation of two states of a 3D city model. This framework defines both the data structure of such an approach, as well as the methodology according to which two existing 3D city models can be compared, associated and stored with their correspondences in 4D. The methodology is defined as six individual steps that have to be undertaken, each with its own individual requirements and goals that have to be challenged. We, also, provide some examples and considerations for the way those steps can be implemented.

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