A state-of-the-art review of built environment information modelling (BeIM)

Elements that constitute the built environment are vast and so are the independent systems developed to model its various aspects. Many of these systems have been developed under various assumptions and approaches to execute functions that are distinct, complementary or sometimes similar. Also, these systems are ever increasing in number and often assume similar nomenclatures and acronyms thereby exacerbating the challenges of understanding their peculiar functions, definitions and differences. The current societal demand to improve sustainability performance through collaboration, whole-systems and through-life thinking, is driving the need to integrate independent systems associated with different aspects and scales of the built environment to deliver smart solutions and services that improve the wellbeing of citizens. The contemporary object-oriented digitization of real world elements appears to provide a leeway for amalgamating modelling systems of various domains in the built environment which we termed as built environment information modelling (BeIM). These domains included Architecture, Engineering, Construction and Urban Planning and Design. Applications such as Building Information Modelling, Geographic Information Systems and 3D City Modelling systems are now being integrated for city modelling purposes. The various works directed at integrating these systems are examined revealing that current research efforts on integration fall into three categories: (1) data/file conversion systems, (2) semantic mapping systems and (3) the hybrid of both. The review outcome suggests that a good knowledge of these domains and how their respective systems operate is vital to pursuing holistic systems integration in the built environment

3D mosaic documentation using close range photogrammetry

The paper describes the close range photogrammetric survey of a roman mosaic stored at Regional Archaeological Museum “Antonino Salinas” in Palermo (Italy). The aim of the work is the production of a full-scale representation (scale 1:1) of the mosaic useful for documentation and restoration processes. The research has allowed evaluating limit and potentiality of image-based approach using photogrammetric and computer vision (Structure for Motion) techniques in a context where the metric point of view is a very important factor

Simuladores de conducción urbanos: una técnica de optimización de bases de datos visuales utilizando aspectos perceptivos

El objetivo del presente artículo es exponer una técnica de optimización de entornos virtuales urbanos, los cuales constituyen bases de datos visuales orientadas a su utilización en simuladores de conducción. La base de la técnica se fundamenta en la identificación de aquellos factores que intervienen en el diseño constructivo del escenario virtual, determinando si son estadísticamente significativos en localidad y en el grado de realismo percibidos por el usuario del simulador gráfico. Este planteamiento supone una nueva vía de simplificación de este tipo de escenarios complejos ya que permite decidir la combinación óptima de modificaciones en las geometrías de los modelos, de tal forma que la base de datos visual resultante se comporte adecuadamente en tiempo real sin comprometerla latencia de la simulación y mostrando al mismo tiempo al usuario final un escenario totalmente reconocible e inmersivo. Se establece un modelo estadístico basado en el diseño de experimentos donde se estudia el efecto que, sobre cada una de las variables respuestas elegidas, tienen el conjunto de factores de diseño del escenario virtual. El modelo ha sido validado experimentalmente en un escenario virtual implementado en un simulador de conducción de bajo coste. La ventaja fundamental de esta contribución es la asignación selectiva de los recursos necesarios a la hora de modelar las geometrías del escenario, permitiendo la reducción de costes y tiempos de desarrollo durante el proceso de generación 3D

3D mosaics survey: analysis of photogrammetric/computer vision approach in a metrological context

The goal of the paper is evaluate photogrammetric/computer vision approach in a metrological context for 3D mosaics survey. The aim of the mosaics survey is the production of a full-scale representation (scale 1:1) useful for the documentation and for the restoration processes. In order to evaluate the optimal photogrammetric/computer vision workflow in this work three different surveys have been done for three mosaics with different size and location. Two of these are stored at Regional Archaeological Museum “Antonino Salinas” in Palermo (Italy) and the other one is stored at Regional Archaeological Museum “Baglio Anselmi” in Marsala (Italy). The research has allowed to show the potentiality and the issues of photogrammetric/computer vision approach for the 3D mosaic documentation

Semi-Automated Building Footprint Extraction, Delineation And 3D Visualisation Of The University Of The Philippines Main Campus From LIDAR Data Using GIS-Based Open Source Software

The advent of three-dimensional building footprint extraction and visualization has recently been explored due to its applications in urban planning, transportation, environmental monitoring, and modelling. Through the use of LiDAR (Light Detection and Ranging) data products such as Digital Terrain Model (DTM) and Digital Surface Model (DSM), useful information such as elevation, size, and shape can be obtained from the processed point clouds. Different studies regarding building extraction procedures have been conducted and explored. Algorithms have also been developed using LiDAR and GIS-based software that assume a rectangular form of polygons as building structures. As such, this study discusses an approach in developing a semiautomated building footprint extraction and three-dimensional visualization of the University of the Philippines (UP) main campus using solely LiDAR data and GIS-based open source software - QGIS Chugiak Version and GRASS 7.0. The UP-Diliman Campus situated in Quezon City, Philippines consists of various polygonal structured buildings which makes it a good subject area for this study. The proposed scheme composed of three major parts: LiDAR pre-processing, building footprint extraction and delineation, and three-dimensional building visualization. Normalized digital surface model (nDSM) can be generated using DTM and DSM. Under building footprint extraction and delineation, four parameters were set: height threshold, area scope, topographic modelling, and smoothing tolerance. For the classification by height, a threshold is set to remove structures with height less than the predetermined value of elevation. Classification by area removes the objects with areas that do not fall within the predetermined area scope. Topographic modelling is used mainly to separate building from other entities. Smoothing tolerance simplifies building outlines. The accuracy assessment for the extraction and delineation is quantified using ground truth data in comparison with the extracted polygons. As compared to manual digitization of building polygons, this semi-automation can be more efficient in extracting and delineating building footprint in areas with large scope. Experimental results indicate that the proposed scheme provides a promising solution for 3D building extraction and delineation using LiDAR data processed in QGIS Chugiak Version and GRASS 7.0. This methodology is a valuable tool for urban planning and modelling

Completing the Jigsaw: The Recent Development of the Maritime Boundaries in the Timor Sea

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Survey and modelling for the bim of Basilica of San Marco in Venice

The Basilica of San Marco is a singular case in the field of Cultural heritage, as it constitutes a construction site always active for the maintenance and preservation of the basilica itself. The continuous intervention of conservation, due to the particular environmental conditions of Venice and the opening to the public, together with the complexity of the building itself, imposes the need to identify an optimized management system. For this reason, in 2013 the Procurator of St. Marco Basilica commissioned the construction of a 3D model of the Basilica to be used for the creation of a BIM. The model must meet the required precision of the scale of 1: 50, and should also include, in addition to the geometric description, a description of the mosaic and marble surfaces of the basilica through high resolution orthophoto which are essential for the restoration of the mosaics. The complexity of the church and the large and continuous flow of public led to work in non-optimal conditions especially for the acquisition stage. The basilica has certain peculiarities that led to some important choices, for example the use of photogrammetry instead of laser scanning technique. The same technique was preferred also by the need to realize, in addition to the geometric model, high-resolution orthophotos of marbles and mosaic surfaces. The modelling of the basilica has highlighted a number of problems related to the building features. The basilica, indeed, is the result of the juxtaposition of elements (capitals, columns) with different origin, which therefore cannot be standardized in special libraries. Moreover, especially in the extensive mosaic areas, there are not edges that characterize the architecture, but only beveled surfaces. This has resulted in a change also in the modeling paradigm with the need to identify alternative systems even for the construction of simple elements. Therefore, we decided to model using NURBS since it is the method that allows greater adherence to reality and, at the same time, a model with acceptable dimensions in terms of navigation and usability. Only the most sculptural pieces such as capitals and statues have been replaced by mesh models. As we were interested in different elaborations, the results of this work are a geometric NURBS model for the subsequent insertion into BIM environment, with the possibility of extracting two-dimensional drawings such as plans and sections, a mesh model with low resolution textures for online navigation and high resolution orthophotos. The survey work and modeling has been almost completed for the interior of the basilica whereas only the external remains to be acquired and modeled. For the management of the entire work it was decided to use the data organization system already used by the Politecnico di Milano for the Duomo di Milano. The BIM3DSURVEY system will be essential not only to manage the finished model, but it has been very useful also during the construction phase because it allows us to divide the entire work into more work units. However, this system required some changes to meet the peculiarity of this BIM, in particular the need to append and link the orthophotos to real surfaces, in order to use the model also as a spatial index for the images