Cuong Vu | DX Construction

DX CONSTRUCTION architect portfolio

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CITYGML & DIGITAL CITY MODEL

CITYGML STRUCTURE: MODULE COMPONENTS CityGML is an open standardised data model and exchange format to store digital 3D models of cities and landscapes. It defines ways to describe most of the common 3D features and objects found in cities (such as buildings, roads, rivers, bridges, vegetation and city furniture) and the relationships between them.

CityGML is a common information model and XML-based encoding for the representation, storage, and exchange of virtual 3D city and landscape models. CityGML provides a standard model and mechanism for describing 3D objects with respect to their geometry, topology, semantics and appearance, and defines five different levels of detail.

Plateau Platform - MLIT

CityGML Structures: Semantics & Geometry

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BIM TO 3DGIS Despite apparent similarities between CityGML and IFC formats at a high level, there are major differences between the two. The conversion to CityGML involves both geometric calculations and the mapping of semantics. While IFC models are built using mostly primitives and swept solids in combination with Constructive Solid Geometry (CSG), CityGML only uses Boundary-representation IFC: Open standard for Building Information Models (BIM) CityGML: Open standard for City information models

FROM IFC TO CITYGML

Differences of IFC & CityGML

By using FME tools, we can convert IFC model to CityGML model.

FME is data conversion technology that features built-in support for both the Industry Foundation Class (IFC) and CityGML formats.

IFC MODEL

IFC’S ATTRIBUTES

FME TOOL

CITYGML MODEL

CITYGML’S ATTRIBUTES

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3D RECONSTRUCTION ALGORITHMS In the digital transformation era, leveraging algorithms to convert 3D point cloud data into 3D CAD models plays a pivotal role in the creation and management of Digital Twins.

A Digital Twin is a virtual representation of a physical asset, system, or environment, and it offers real-time insights, monitoring, and simulations. By employing sophisticated algorithms, organizations can seamlessly bridge the gap between physical entities and

their digital twins. This process allows for the continuous synchronization of real-world changes with the digital model, ensuring an upto-date and accurate representation of assets or environments.

Digital Twins enable proactive maintenance, performance optimization, and scenario testing, leading to improved decisionmaking and resource management. They are

invaluable tools in diverse sectors, such as smart cities, manufacturing, and healthcare, where they facilitate data-driven strategies for enhanced efficiency, sustainability, and resilience, ultimately driving innovation and competitiveness in today’s rapidly evolving digital landscape.

CONVEX HULL ALGORITHM The Convex Hull is a fundamental algorithm in computational geometry used to find the smallest convex polygon that encloses a given set of points in a plane. This convex polygon is called the “convex hull,” and it represents the outer boundary of the points.

POINTCLOUD DATA

CONVEX HULL OUTLINER

OUTLINER

MASS

Convex Hull’s code snippet in Python

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RANSAC ALGORITHM The Random Sample Consensus (RANSAC) algorithm is a robust and widely used method for fitting models to data in the presence of outliers or noisy data. It is particularly useful when you have a set of data points

RANSAC ALGORITHM

POINTCLOUD DATA

SURFACE DETECTION BY RANSAC

SURFACE EQUATION

RANSAC’S CODE SNIPPET IN PYTHON

RANSAC ALGORITHM

that may contain outliers, and you want to estimate a model that best fits the inlier data points while ignoring the outliers. RANSAC is commonly employed in computer vision, image processing, and various other fields where data modeling is required.

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OTHER DX RESEARCHES AND ACTIVITIES

SEMINARS AND FIELD TRIP CACBON FOOTPRINT CALCULATION WITH BIM MODEL INTRODUCTION

I sometimes give presentations to my colleagues and propose new ideas or technologies during company seminars. These discussions and feedback sessions are valuable for refining our work and enhancing our ideas. Additionally, we occasionally organize field trips to visit other companies or construction sites to better understand their technologies and identify opportunities for improvement on our own construction sites.

DX CONSTRUCTION EXHIBITION We frequently participate in DX construction fairs, which provide us with a great opportunity to showcase our work and learn from other companies. Sometimes, these fairs have a community-oriented focus, allowing us to inspire people, especially the younger generation, to take an interest in technology and the future of the construction industry.

Kids having fun with VR. 360 video of real construction site

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DRONE

3D PRINTING

Flying drone pratice

Using 3D printer and create replicate 3D parts to replace broken ones

PHOTOGRAMMETRY Photogrammetry is a technique used to create 3D models of objects or environments by analyzing and processing multiple 2D images taken from different angles.

Point Cloud to BIM Model: The point cloud can be used as a reference or source data to create

a BIM model. BIM software can use the point cloud data to create a 3D model by fitting the points with geometric elements like walls, floors, and roofs. This process is known as “point cloud-to-BIM conversion.

Using photogrammetry and point clouds for BIM

modeling is particularly useful when renovating or retrofitting existing structures. It allows for the creation of accurate as-built models that can be used for planning and designing modifications or upgrades.

SET OF PHOTOS

POINTCLOUD

BIM MODEL

Metashape

Revit

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FREELANCE WORKS AND REVIEWS WORKS > Diagrams > BIM modeling > Structure Exploding > Environmental Analysis > Architecture details > Circulation Plan > Pamphlet design

CIRCULATION DIAGRAM

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PROFILE During the pandemic, I began working with private clients on various small projects from around the world. As a solo entrepreneur, I handled negotiations, created proposals, and made sure clients were happy. This commitment to doing great work has brought back repeat clients and new projects. My journey as an entrepreneur has not only improved my business skills but also made me even more dedicated to surpassing client expectations.

REVIEWS FROM CLIENTS

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CLIENT’S SATISFACTION