The utilization of 4D-BIM in the demolition phase of buildings has not gained widespread attention. Therefore, this study aims to clarify the challenges faced in effectively utilizing 4D-BIM in the demolition project. The method of this study involves applying 4D-BIM in the actual demolition project, observing and evaluating its role in the process of demolition planning and execution, exploring the challenges faced, and the potential effects that can be achieved in the utilization of 4D-BIM during the demolition phase, and providing prospects for its future applications. During the process of creating the 4D-BIM for the actual demolition project, we encountered several challenges related to generating BIM data and utilizing BIM software. Although these issues required substantial time and effort to resolve, using 4D-BIM effectively discussed and created demolition solutions in the actual demolition project. It enables the visualization of multiple demolition schemes and enhances the intuitive understanding of these solutions. The results of attempting to use 4D-BIM in the actual demolition project show that, despite challenges such as issues with BIM data creation and inadequate BIM software functionalities affecting the efficient generation of 4D-BIM data, the effects demonstrated by 4D-BIM indicate its potential for application in the demolition phase.

Potential and Insufficiency of Application of 4D-BIM for the Building Demolition Process

In the rapidly advancing digitization of the Architecture, Engineering, and Construction (AEC) industry, end-users of buildings are seeking a diverse supply of Building Information Modeling (BIM) data to meet their intended use. However, in a Common Data Environment (CDE) managed by a specific organization, the project-oriented platform philosophy, management structure, and security risks make it difficult to release and distribute data to third parties other than project members. One potential solution is the public release of BIM data using blockchain technology. However, there is insufficient research on how to record the contents of large volumes of BIM data in a blockchain and improve data searchability from users and applications. 
Therefore, this paper proposes a metadata, IFC Catalog, created by summarizing information from Industrial Foundation Classes (IFC), a standard specification for BIM data representation, with the perspective of minting it as Non-Fungible Tokens (NFT). The IFC Catalog consists of JSON data composed of Static Fields extracted from IFC and Custom Fields tailored to the purpose of the data. It is lighter in comparison to the BIM data itself, allowing users to easily review its content in applications for searching, buying, and managing NFTs. In the created minimum viable product, it was possible to display information from IFC files recorded in the IFC Catalog on the application interface with simple controls. This implementation demonstrated that large volumes of BIM data can be stored using blockchain technologies and in doing so, improved the data searchability.

Improving Metadata of Non-Fungible Tokens for Multipurpose BIM Data Distribution

Various real-world applications are implemented to make life comfortable, convenient, and safe. The data and applications are tightly coupled. Application implementation costs are high because data reusability is low. Data reusability is increased by implementing a mechanism that collects data according to the requirements of real-world applications, builds a digital twin (DT) from the collected data, and combines the data with real-world applications. Therefore, platforms providing data to creating DTs are emerging. However, DT data platforms have the following problems. As DT data platforms proliferate, they are distributed across multiple platforms. Consequently, it is difficult for real-world application implementers to obtain data for creating a DT. Data reprocurement increases application implementation costs. Herein, methods for solving data reusability problems are proposed. A function for outputting metadata representing the spatial structure was implemented on spatial data platforms. Data delivery interfaces are implemented in data platforms that manage data related to spatial data. The method for accessing the related data is described in the metadata section. In this study, prototype systems for building information modeling (BIM) data were implemented using the proposed method. The industry foundation classes (IFC) model server, which exports metadata, was implemented. The API Server, which manages the building of the 3D model data, was implemented. The endpoints for accessing the 3D data API server are described in the metadata.

Multi-platform data search and access method to compose digital twins using metadata

In recent years, the term "metaverse" has been attracting a lot of attention due to Facebook's name change and other factors. However, this is not the first time that the metaverse has attracted attention; it had already gained momentum at the beginning of the 21st century. With this background, it can be said that the technology has already reached a certain degree of maturity and is entering the stage of social implementation. On the other hand, the social discussion on what it means for humanity and how society should deal with it remains immature. The purpose of this paper is to outline the metaverse as a concept to fill this gap. This paper will discuss how the Internet and VR have been positioned in society, while pointing out that they have closely overlapped but have maintained a delicate distance. It will then focus on cases and phenomena that cannot be distinguished between the two, and point out that the key to exploring the uniqueness of the metaverse lies in the subtle relationship between the two.

Metaverse as Concept

The Architectural creation is always affected by technological development and available resources. The presence of computation and the advent of artificial intelligence opens new ways in architectural design and implementation, which is not only embodies in the technical application of the new medium, but present in the new design logic as well.
This paper provides an overview about the three main branches of artificial intelligence starting with a short introduction of the long-lasting relationship of computation and architecture. Starting from a theoretical base and reaching to the architectural application of symbolicism, connectionism and actionism. The achievement of the research will point out how digital tools foster a novel design approach in architecture. 


Prospects of AI in Architecture: Symbolicism, Connectionism, Actionism

COVID-19 has been spreading worldwide since 2020. Although the World Health Organization recommends maintaining a physical distance of at least 1 m among people, the Japanese government recommends 2 m. In this study, we used deep learning and other techniques to statistically compare and verify the change in physical distance between pedestrians on a sidewalk in a large Japanese city before and after the COVID-19 pandemic. A video-based approach was used to accomplish this. The video before the COVID-19 pandemic was recorded in October 2018 in the Namba area of Midosuji, Osaka City. For comparison, new videos were recorded at the same location in October 2020. YOLOv3 SPP was applied to automatically extract a large number of pedestrians on the street. Three observation areas were set on the sidewalk within the target area, and the physical distances between the pedestrians were measured. Two indices were used to measure the physical distance: the average nearest neighbor and Ripley’s K-function. Thus, the change in the physical distance between people on the street, before and after the COVID-19 pandemic, could be quantitatively and statistically compared. The results showed an increase in physical distance after the COVID-19 pandemic, which depended on the state of behavior, density, and human relations.

Comparison of Physical Distances Between Pedestrians on a Street in the Central Area of Osaka City Before and After the Covid-19 Pandemic Based on Deep Learning Techniques

This study proposes that the Building Information Model should aim to become a data service provider in order to expand the possibilities of utilizing BIM data. In order to construct a BIM server, this study devised a design method for creating a database of IFC, an international standard specification. We have developed a program to automatically create an RDB from IFC data using various mapping rules. Furthermore, benchmark tests were conducted to compare the performance difference and behavior of each DB to clarify the appropriate RDB design method for storing IFC data. As a result, we believe that the method of creating a table for each entity and maintaining the inheritance relationship by giving it a foreign key is the most appropriate method for constructing an IFC server at present. As BIM continues to develop, there is a growing momentum to share and utilize BIM data on cloud servers. We will contribute to the realization of such an ideal.

The study of Building Information Model server focusing on IFC to RDB conversion

Extending the existing Building Information Modeling (BIM) log mining approach, the paper proposes a novel method for visual analytics on clustered logs collected from multiple organizations. Implementing multiple datasets as case study processes demonstrated that the analytics effectively visualized the structured BIM events in command, organization, and user layers. Identified four major cluster groups correspond to logs' commonality and level of contribution significantly helped decipher recorded BIM activities without requiring background knowledge. The proposed technique allows the intercomparison of BIM activity that enables data-driven skill design for individuals and organizations. Such monitoring allows BIM users and teams to respond to transient project situations dynamically, which is expected to mitigate the observed major BIM problems of skill and management. The method contributes to increasing the likelihood that the model will be used throughout the project duration, leading to enhanced BIM's expected value in projects.

AIS-J 2021 Journal Submissions