3D Geographic Information System Research Articles

RIS3D: A Referenced Information System in 3D

3D Geographical Information Systems (GIS), Building Information Modeling (BIM),… These words are increasingly used for Cultural Heritage studies to refer to the necessity to connect heterogeneous data with a 3D model. In this article, we introduce and formalize the notion of RIS3D (Referenced Information System in 3D), which extends the concept of GIS to 3D supports and generalizes it. For this purpose, we propose a generic and modular client-server approach that brings the required flexibility, extendibility, and sustainability to deal with heterogeneous data. For queries and their visualization in a 3D environment, we push forward the notions of layers and markers. We also provide the readers with our technical choices that allowed us to develop our own implementation of a RIS3D solution. We demonstrate it on a real-case scenario: the preservation of the Lascaux painted cave where our solution has been deployed and is in use. The proposed notion and generic architecture of RIS3D, its implementation, and its deployment show the suitability of such an approach and its potential applications.

Improved IDW Interpolation Application Using 3D Search Neighborhoods: Borehole Data-Based Seismic Liquefaction Hazard Assessment and Mapping

Traditional inverse distance weighting (IDW) interpolation is a process employed to estimate unknown values based on neighborhoods in 2D space. Proposed in this study is an improved IDW interpolation method that uses 3D search neighborhoods for effective interpolation on vertically connected observation data, such as water level, depth, and altitude. Borehole data are the data collected by subsurface boring activities and exhibit heterogeneous spatial distribution as they are densely populated near civil engineering or construction sites. In addition, they are 3D spatial data that show different subsurface characteristics by depth. The subsurface characteristics observed as such are used as core data in spatial modeling in fields, such as geology modeling, estimation of groundwater table distribution, global warming assessment, and seismic liquefaction assessment, among others. Therefore, this study proposed a seismic liquefaction assessment and mapping workflow using an improved IDW application by combining geographic information system (GIS) (ArcGIS (Esri, Redlands, CA, USA)), NURBS-based 3D CAD system (Rhino/Grasshopper (Robert McNeel & Associates, Seattle, WA, USA)), and numerical analysis system (MATLAB (MathWorks, Natick, MA, USA)). The 3D neighborhood search was conducted by the B-rep-based 3D topology analysis, and the mapping was done under the 2.5D environment by combining the voxel layer, DEM, and aerial images. The experiment was performed by collecting data in Songpa-gu, Seoul, which has the highest population density among the OECD countries. The results of the experiment showed between 7 and 105 areas with liquefaction potentials according to the search distance and the method of the approach. Finally, this study improved users’ accessibility to interpolation results by producing a 3D web app that used REST API based on OGC I3S Standards. Such an approach can be applied effectively in spatial modeling that uses 3D observation data, and in the future, it can contribute to the expansion of 3D GIS application.

INVESTIGATION OF THE SHADOW EFFECT OF URBANIZATION ON GREEN AREAS WITH SHADOW IMPACT ANALYSIS

Today, the use of information technologies has made life easier and helps people to take precautions against problems that may arise in the future. 3D Geographic Information Systems is also used for various purposes to facilitate human life today. One of these goals is to improve the foresight ability in plans. In the studies carried out until today, the power of 3D to produce solutions to various problems in the world is revealed. In this study, the effects of urban shadowing because of wrong urbanization have been investigated by using the power of 3D Geographic Information Systems. The data was provided via Open Street Map, which is an open-source map provider. The obtained data were analyzed and a park which is the surrounding area is not yet developed was determined. In the aim of the study, new buildings were added around the park by evaluating the direction of urban growth and possibilities, and the effect of the shadow it created on the sunbathing time of the park was investigated. It is obvious that social areas such as park areas are important for people to reach the sun they need. As a result, it is necessary to investigate the shadow effects of newly constructed buildings in order to increase the sunshine duration in the park areas.

An innovative approach for retrieval of gridded urban canopy parameters using very high resolution optical satellite stereo

ABSTRACT Paucity of information on Urban Canopy Parameters (UCPs) is considered as one of the major reason behind limited urban climate research and modelling in developing region of Asia, Africa, and Latin America. UCPs define those characteristics of urban built form which have direct or indirect influence on urban climate. Most of the studies in developed world have utilized 3-Dimension (3D) Geographic Information System (GIS) database either developed from ground survey or Remotely Sensed (RS) data such as Aerial Photographs, Airborne Light Detection and Ranging (LiDAR) and high-resolution Interferometric Synthetic Aperture Radar (InSAR) data for retrieval of UCPs. However, non-existence of 3D GIS database and limited availability of above RS datasets in developing region necessitates to employ widely available low-cost alternative datasets for retrieval of UCPs. Hence, this study focuses on retrieval of UCPs by employing Very High Resolution Satellite (VHRS) optical stereo data, which has repeat availability, low cost and extensive coverage, in a highly dense and complex urban environment with a challenging composite climate like Delhi, India. A novel methodology for extraction of gridded UCPs from VHRS optical stereo data has been developed in this study to overcome the limitation of extraction of individual building footprint in dense and compact urban built-up. The validation of key UCPs such as building height (Mean error, Root Mean Square Error (RMSE) and Mean Absolute Error <1 m in all height groups), Building Surface Area (Accuracy 84.27%) and Sky View Factor (RMSE = 0.046 and correlation = 0.94) with ground measurements has displayed reasonable accuracies. Hence, the study demonstrates successfully the use of VHRS optical satellite stereo data for generation of gridded UCPs in a highly heterogeneous and dense urban built-up environment. The developed approach is globally replicable in any city of any country.

DEEP LEARNING FOR 3D BUILDING RECONSTRUCTION: A REVIEW

Abstract. 3D building reconstruction using Earth Observation (EO) data (aerial and satellite imagery, point clouds, etc.) is an important and active research topic in different fields, such as photogrammetry, remote sensing, computer vision and Geographic Information Systems (GIS). Nowadays 3D city models have become an essential part of 3D GIS environments and they can be used in many applications and analyses in urban areas. The conventional 3D building reconstruction methods depend heavily on the data quality and source; and manual efforts are still needed for generating the object models. Several tasks in photogrammetry and remote sensing have been revolutionized by using deep learning (DL) methods, such as image segmentation, classification, and 3D reconstruction. In this study, we provide a review on the state-of-the-art machine learning and in particular the DL methods for 3D building reconstruction for the purpose of city modelling using EO data. This is the first review with a focus on object model generation based on the DL methods and EO data. A brief overview of the recent building reconstruction studies with DL is also given. We have investigated the different DL architectures, such as convolutional neural networks (CNNs), generative adversarial networks (GANs), and the combinations of conventional approaches with DL in this paper and reported their advantages and disadvantages. An outlook on the future developments of 3D building modelling based on DL is also presented.

Development of a Conceptual Data Model for 3D Geospatial Road Management Based on LandInfra Standard: A Case Study of Korea

In practice, road management data are typically managed in two-dimensional (2D) geospatial forms. However, 2D geographic information system (GIS)-based road infrastructure management data have limitations in their representation of complex roads, such as interchanges, bridges, and tunnels. As such, complex and large road network management data cannot be adequately managed in a 2D GIS-based form. This study discusses the use of the LandInfra standard for road infrastructure management in Korea, considering its focus on land and civil engineering infrastructure facilities. To facilitate the transition from 2D to 3D GIS, we analyzed existing road management models of road pavement and road register information and created Unified Modeling Language (UML) class diagrams depicting these models. Then, existing road management classes and LandInfra classes were mapped. Based on the results, we propose a road management model based on the Facility, Alignment, and Road parts of LandInfra. For its implementation, several classes of the proposed data model were encoded into InfraGML using real-world data input. Taken together, this study shows how the LandInfra standard can be extended and applied to the field of road infrastructure management in Korea, supporting the transition from a 2D to a 3D GIS-based model.

3D Campus Map Towards Sustainable Development and Infrastructure Management In UPNM

Abstract 3D technology is used in GIS maps to create descriptive graphics that accurately depict the size of real-world items. In a wide variety of various areas, 3D models aid in appearance and survey. For example, 3D maps may depict the height of a building or a mountain in addition to its location. 3D tools must be utilized in conjunction with 2D GIS and then visualized in a 3D environment. The current UPNM campus map accessible to students and staff is not sufficiently helpful and hardly identified its whereabouts. This project was undertaken to develop a web-based 3D campus map and analyze specifically the campus’s area zoning. This study uses a personal computer with Esri CityEngine software to develop the 3D campus map and ArcGIS Online to publish the web-based 3D campus map. The data was acquired by downloading the base map of UPNM from OpenStreetMap (OSM). Completion of data processing results in a web-based 3D UPNM campus map with area zoning. The finding shows that the 3D map, using the Geographical Information System (GIS) platform, is more informative and attractive than the 2D map due to the attribute and spatial data. In addition, the capabilities of the 3D map to visualize and show the campus area and area zoning in the map can be managed according to the structural information. All in all, it can be concluded that this web-based 3D map contributes towards the sustainability of the UPNM infrastructure and campus while facilitating campus maintenance and rehabilitation.

Re-viewing Pompeian domestic space through combined virtual reality-based eye tracking and 3D GIS

This article presents an innovative methodology in which virtual reality-based eye-tracking techniques and 3D Geographical Information Systems are employed to record and measure human visual attention within the virtually reconstructed space of a Pompeian house.

MANAGING 3D ASSET MANAGEMENT USING CITYGML CONCEPT

In the last decades, three-dimensional asset management is one of the significant practices that is rapidly being used nowadays. Nowadays, 3D GIS has been applied in various applications, especially asset management. A major problem that faces the country at present is the lack of effective tools for managing and maintaining the assets. Currently, in Malaysia, there has been a system that develop by the government named Malaysia Immovable Asset Management System (MySPATA) that is used for the recording, managing, and monitoring government immovable assets. However, this system has not been very successfully utilized due to data complexity and complication in the documentation. This also happens because there are issues involving the management of spatial data due to the growing complexity in infrastructure and limitation of applications. In the surge of digitized economies and industrial improvement, the usefulness of data visualization is becoming increasingly significant in sectors such as smart city planning, construction, management, and services. Therefore, for this to happen, integration between 3D asset management and the CityGML concept is needed This paper focuses on managing 3D asset management using the CityGML concept. CityGML is an independent geospatial information model for semantic 3D city and landscape models that contain various features and modules such as spatial information, data integration, and data visualization. Integration of current technology which is Geographical Information System (GIS) and CityGML concept being employed for 3D asset management. A 3D asset management modeling is being developed using the CityGML standard to track spatial assets, maintain asset records, and sustain an accurate inventory of assets. Thus, in the future, an effective GIS database management will be developed to ensure adequate system performance and operational.

3D-GIS Parametric Modelling for Virtual Urban Simulation Using CityEngine

ABSTRACT Modelling and visualization of three-dimensional (3D) models for cities is a great challenge for computer software and graphics. Recently, 3D city modelling has grown due to advances in applications accompanying the information technology revolution. 3D Geographic Information Systems (3D-GIS) have evolved enormously due to the availability of large-scale 3D modelling techniques. These technologies have become very important in representing large cities and conducting various analyses in the city’s virtual environment to support urban decision-making. CityEngine is one of the most recent 3D-GIS modelling applications. CityEngine can be described as parametric modelling using Procedural Modelling (PM) to create 3D urban elements through macros and routines. This paper highlights the importance of 3D Procedural Modelling (PM) of cities in the GIS environment using ESRI CityEngine and presents a parametric concept for designing urban spaces. This issue has been addressed in three respects. First, discuss the concept and strength of parametric design. Second, the concept of procedural modelling and its power to generate complex 3D models using a set of rules is discussed. Finally, CityEngine was evaluated through a real-world case study of a neighbourhood in the new city of Beni-Suef, Egypt. The results confirm the effectiveness of CityEngine as a 3D-GIS modelling software that generates dynamic 3D models from 2D spatial data. While the results are promising, it is important to investigate more complex cases. The CityEngine modelling approach enables comprehensive urban analyses such as sequence vision, façade studies, urban fabric and character, and statistical operations based on attribute database.

Documenting cultural heritage in an INSPIRE-based 3D GIS for risk and vulnerability analysis

PurposeThe study, within the Increasing Resilience of Cultural Heritage (ResCult) project, aims to support civil protection to prevent, lessen and mitigate disasters impacts on cultural heritage using a unique standardised-3D geographical information system (GIS), including both heritage and risk and hazard information.Design/methodology/approachA top-down approach, starting from existing standards (an INSPIRE extension integrated with other parts from the standardised and shared structure), was completed with a bottom-up integration according to current requirements for disaster prevention procedures and risk analyses. The results were validated and tested in case studies (differentiated concerning the hazard and type of protected heritage) and refined during user forums.FindingsBesides the ensuing reusable database structure, the filling with case studies data underlined the tough challenges and allowed proposing a sample of workflows and possible guidelines. The interfaces are provided to use the obtained knowledge base.Originality/valueThe increasing number of natural disasters could severely damage the cultural heritage, causing permanent damage to movable and immovable assets and tangible and intangible heritage. The study provides an original tool properly relating the (spatial) information regarding cultural heritage and the risk factors in a unique archive as a standard-based European tool to cope with these frequent losses, preventing risk.

Patalan River Basin Flood Plains Exposure and Vulnerability Assessment of Buildings Extracted from Lidar Derived Datasets

Abstract: Philippines, as it is known to be a stopover for Pacific typhoons, is frequently threaten by flood and landslide that endangers the lives of many Filipinos. Great amount of monetary resources are being used up annually because of incidents by annual heavy downpour in this country. The population, their source of revenue and the area are the ones affected by these unfortunate events that causes the country for millions of peso every year. In this regard, there is an obvious need for methods and strategies that will alleviate adverse situations and which will protect human lives, properties and social infrastructure against disaster phenomena. Different important parameters in disaster risk management such as earth observations, Light Detection and Ranging (LiDAR) and Geographic Information System (GIS) were integrated and utilized in this study. This study dealt with mapping and assessment of buildings that might possibly be exposed and vulnerable to flooding based on the simulated flood maps at different rainfall scenarios in Patalan River Basin, Pangasinan, Philippines. The assessment was done through GIS overlay analysis of the CLSU PHIL-LiDAR 1 Project outputs, the 3D building GIS database and flood hazard maps. The 3D building GIS database was generated through processes and analysis of various datasets that include 1m resolution LiDAR Digital Elevation Models (DEMs), geo-tagged video captured data and high resolution images in Google Earth. The flood hazard maps with different hazard levels were generated with the use of flood models developed using the combined HEC HMS and HEC RAS. Results of this study were series of flood exposure maps and vulnerability maps with statistics at different rainfall scenarios. The number of houses, businesses and other types of building at risk of being flooded was quantified. It was observed that buildings exposed and vulnerable to flood are highest at 100 year return period. With the total of 129,800 building features extracted, results show that at 100 year return period there will be 61,377 buildings, 16,806 buildings and 23 buildings at low, medium and high hazards, respectively. Moreover, also at 100-year return period, a total of 12,569 buildings, 8,628 buildings and 17,795 buildings were identified that had high vulnerabilities to flood in terms of height at low, medium and high hazards, respectively. These produced maps can provide valuable information to the local government units and the communities around Patalan river basin in their flood disaster management through appropriate and riskconscious development in order to prevent further build-up risks. Through these maps, it is easier to disseminate information that is more realistic to the residents about the hazardous areas and to help them act on warning and evacuating measures. Keywords: Geographic Information System, flood, database, exposure, hazard

Research on Simulation of Distribution Network Engineering Scene Based on 3D GIS Technology

With the rapid development of the power system and the increasing complexity of the power grid structure, users’ demand for information-based management of the power distribution network is growing, and the need to improve various power production service standards is becoming increasingly urgent. Geographic information systems (GIS) are a natural combination of geographic and data attributes that are particularly well suited to the management of urban pipeline systems such as distribution and telecommunication networks. This paper discusses the current application characteristics and challenges of 3D GIS in the power system. A 3D graphic analysis model of the power grid and its realization method are proposed using 2D GIS and scene simulation technology combined with object-oriented design method. The problems that exist in current urban distribution facility management are solved in this paper through the effective integration of information construction and distribution facility management, and the goal of refined management is achieved on this basis. More and more complex 3D spatial data can be processed more realistically and intuitively with 3D GIS.

A ship navigation information service system for the Arctic Northeast Passage using 3D GIS based on big Earth data

ABSTRACT Research on Arctic passages has mainly focused on navigation policies, sea ice extraction models, and navigation of Arctic sea routes. It is difficult to quantitatively address the specific problems encountered by ships sailing in the Arctic in real time through traditional manual approaches. Additionally, existing sea ice information service systems focus on data sharing and lack online calculation and analysis capabilities, making it difficult for decision-makers to derive valuable information from massive amounts of data. To improve navigation analysis through intelligent information service, we built an advanced Ship Navigation Information Service System (SNISS) using a 3D geographic information system (GIS) based on big Earth data. The SNISS includes two main features: (1) heuristic algorithms were developed to identify the optimal navigation route of the Arctic Northeast Passage (NEP) from a macroscale perspective for the past 10 years to the next 100 years, and (2) for key sea straits along the NEP, online local sea-ice images can be retrieved to provide a fully automatic sea ice data processing workflow, solving the problems of poor flexibility and low availability of real sea ice remote sensing data extraction. This work can potentially enhance the safety of shipping navigation along the NEP.

3D GIS Interactive Visualization of the Archaeological Sites in Qatar for Research and Learning

This project provides a proficient approach to coordinate archeological ex-ercises, information administration, digital object representation, and spa-tial investigation. The proposed framework furnishes the client with the in-tuitive investigation of the 3D model artifacts along with detailed infor-mation on specific points of interest alongside their 3D geographic infor-mation system (3D GIS). A parallel result is the utilization of fully trans-parent and cost-effective open source tools and free software. The work ad-dressed the creation of a computerized system that aids classification, ad-ministration, and representation of archeological discoveries inside a 3D web-based repository; and the utilization of 3D digital models as a restora-tion of the artifacts to allow navigation through the data; besides enabling 3D GIS to spatially store, share, envision and examine complex archeologi-cal components; This work is one of the first of its type in Qatar to archive and record all of the archeological data from the Murwab site in Qatar.

IFC AND CITYGML SEMANTIC TRANSFORMATION FOR 3D GIS

Building information modelling (BIM) and geographical information systems (GIS) domains immensely contribute to a digital representation of architectural and environmental bodies respectively. BIM is endorsed in order to enhance the Architecture Engineering and Construction (AEC) industry process to save time, cost and speed up the project, and more so, to minimise the frequent requests of information by the stakeholders within the industry. On the other hand, the Geographic Information System (GIS) has been increasingly used to generate detailed 3D data, geolocation and spatial analysis. Both BIM and GIS provide 3D data for the development of 3D city models, digital twin, smart city, AEC etc. However, there are significant diverse between the two in terms of their characteristics, scope of interest and focus that makes it difficult to easily be achieved. The amalgamation of the two worlds provides a clear picture of a built environment based on data (geometry and semantics) integration, which reinforces the enhancement of the three-dimensional (3D) applications in general into the digital world. This paper presents a methodology that semantically integrates the two worlds through their standards that is the Industry Foundation Classes (IFC) which is an open standard, selected because it is the typical free standard to exchange data in the BIM world and City Geography Markup Language (CityGML) is the most leading 3D city model standard in 3D GIS. This is carried out by performing a semantic mapping between the two standards, converting the encoding that the two standards use from STEP in IFC(BIM) to XML in CityGML (3D GIS), by providing a basic implementation created using Python to combine the above tasks.

Construction of 3D GIS based on VR and Edge Computing

Geographic Information System (GIS) is a subject that studies spatial information science and computer system for collecting, storing, retrieving, modeling, analyzing and representing geospatial data. GIS not only manages attribute information based on numbers and text, but also manages spatial information based on visual graphics and images. With the rapid development of computer technology, space technology and information technology, the expression form of map is gradually changing from two-dimensional to three-dimensional. 3D GIS can express 3D spatial information in detail and has powerful multi-dimensional spatial analysis function. However, 3D visualization technology can not be immersed in geographic information. The process of requesting information by each end user is energy intensive. If big data processing is adopted, it will greatly increase the computing pressure of big data center. The paper presents a 3D GIS construction method based on Virtual Reality (VR) and edge computing (gis-ve). Specifically, firstly, virtual reality equipment is deployed at the user terminal to realize the organic integration of real scene and virtual object in three-dimensional space, and build a real and perfect three-dimensional real world space. Secondly, under the edge computing architecture, virtual reality applications are deployed on edge computing nodes to reduce the number of device hops transmitted between virtual reality application data and end users, reduce network processing delay and reduce the computing pressure of big data processing center. Then, the deployment problem of GIS is transformed into a performance optimization problem, and the delay and cost are used as evaluation indexes. Finally, an improved artificial bee colony algorithm is proposed to solve the optimal GIS construction scheme. In order to verify the feasibility and effectiveness of this method, the paper compares this method with two other advanced 3D-GIS construction methods, and experiments show that this method performs well in terms of delay and cost.

Extracting 3D Indoor Maps with Any Shape Accurately Using Building Information Modeling Data

Indoor maps lay the foundation for most indoor location-based services (LBS). Building Information Modeling (BIM) data contains multiple dimensional computer-aided design information. Some studies have utilized BIM data to automatically extract 3D indoor maps. A complete 3D indoor map consists of both floor-level maps and cross-floor paths. Currently, the floor-level indoor maps are mainly either grid-based maps or topological maps, and the cross-floor path generation schemes are not adaptive to building elements with irregular 3D shapes. To address these issues, this study proposes a novel scheme to extract an accurate 3D indoor map with any shape using BIM data. Firstly, this study extracts grid-based maps from BIM data and generates the topological maps directly through the grid-based maps using image thinning. A novel hybrid indoor map, termed Grid-Topological map, is then formed by the grid-based maps and topological maps jointly. Secondly, this study obtains the cross-floor paths from cross-floor building elements by a four-step process, namely X-Z projection, boundary extraction, X-Z topological path generation, and path-BIM intersection. Finally, experiments on eight typical types of cross-floor building elements and three multi-floor real-world buildings were conducted to prove the effectiveness of the proposed scheme, the average accuracy rates of the evaluated paths are higher than 88%. This study will advance the 3D indoor maps generation and inspire the application of indoor maps in indoor LBS, indoor robots, and 3D geographic information systems.

A novel 3D-geographic information system and deep learning integrated approach for high-accuracy building rooftop solar energy potential characterization of high-density cities

Accurate rooftop solar energy potential characterization is critically important for promoting the wide penetration of renewable energy in high-density cities. However, it has been a long-standing challenge due to the complex building shading effects and diversified rooftop availabilities. To overcome the challenge, this study proposed a novel 3D-geographic information system (GIS) and deep learning integrated approach, in which a 3D-GIS-based solar irradiance analyzer was developed to predict dynamic rooftop solar irradiance by taking shading effects of surrounding buildings into account. A deep learning framework was developed to identify the rooftop availabilities. Experimental validations have shown their high accuracies. As a case study, a real urban region of Hong Kong was used. The results showed that the annual solar energy potential of the entire building group was reduced by 35.7% due to the shading effect and the reduced rooftop availability. The reductions of individual buildings varied from 13.4% to 74.5%. In spite of the substantial reductions of the annual solar energy, the shading effect could only slightly reduce the peak solar power. In fact, the annual solar energy reduction could be five times higher than the peak solar power reduction. Further analysis showed that simple addition of the respective solar energy potential reductions, caused by the shading effect and the rooftop availability, tends to highly overestimate the total reduction by up to 26%. For this reason, their impacts cannot be considered separately but as joint effects. The integrated approach provides a viable means to accurately characterize rooftop solar energy potential in urban regions, which can help facilitate solar energy applications in high-density cities.

GIS METHODOLOGICAL APPROACH TO DEVELOPING AND FORMING A VISUAL IMAGE OF DOWNTOWN AMMAN

Introduction: Amman’s growth expansion was shaped by its topography (valleys and hills), which generated a special character and patterns of the urban form. The city was built on seven hills, which are connected by steep stairs that serve as pathways to the downtown core. The rapid urbanization caused by uncontrolled population growth, as well as random and unplanned formations that were far from following any kind of aesthetic, resulted in the expansion of the center towards the surrounding seven hills. The continuous intersection of these hills caused their boundaries to blur and melt. As a result of the intense transformation, which is causing the hills’ appearance to become more uniform, their continuing overlap may completely destroy the unique character and imageability of downtown Amman. Methods: This research made use of topographical context analysis and the Geographical Information System (GIS) as well as its 3D modeling function to identify the optimal visibility and viewing angle when looking from the valley towards the hills and between the hills. Results and discussion: We identified the main vistas, i.e., highly significant views, which could subsequently be adopted as the locations for proposing landmark scenarios via 3D model GIS analysis. The projection process helped determine the significant views from the valley towards the hills and between the hills. Overall, three scenarios were proposed for the landmarks, out of which, the best one was chosen. It corresponds to the topographical analysis and the community needs, depends upon the local context and urban fabric, and is optimal for decision-making.