• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.19 no.7
• /
• pp.22-34
• /
• 2020

Three-dimensional (3D) computer-aided design (CAD) models require different levels of detail (LODs) depending on their purpose. Therefore, it is beneficial to automatically simplify 3D CAD assembly models to meet the desired LOD. Feature-based 3D CAD assembly models typically have the lowest and highest feasible limits of LOD during simplification. In order to help users obtain a feasible simplification result, we propose a method to simplify feature-based 3D CAD assembly models by determining the lowest and highest limits of LOD. The proposed method is verified through experiments using a simplification prototype implemented as a plug-in type module on Siemens NX.

• Korean Journal of Construction Engineering and Management
• /
• v.8 no.6
• /
• pp.188-196
• /
• 2007

Because the construction is becoming bigger and the construction environment is rapidly changing, IT/IS(Information Technology and Information System) of the construction is recently suggested with the alternative proposal. So not only is a study progressed in the area of the BIM(Buidilng Information Modeling), VC(Virtual Construction) and CIC (Computer-Integrated Construction) but also of the information database of the construction for building the information infrastructure of the construction in the domestic construction. Because object-oriented 3D CAD improves the efficiency of a design work and includes the object information which can use with the base of the information database of the construction, it has the high value not only in the design level but also in the construction life cycle. But compared with the effect, the use of 3D CAD is sluggish in the construction. In this study, after surveying about lowly using 3D CAD on the point of AEC (Architect-Engineer-Contract), the result is analyzed with AHP(Analytic Hierarchy Process). So the aim of this study is to offer the base to find the solution of the Affecting factors about lowly using 3D CAD.

• The KIPS Transactions:PartA
• /
• v.18A no.3
• /
• pp.81-92
• /
• 2011

There has been a number of attempts to apply 3D CAD data created in the design stage of product life cycle to various applications of the other stages in related industries. But, 3D CAD data requires a large amount of computing resources for data processing, and it is not suitable for post applications such as distributed collaboration, marketing tool, or Interactive Electronic Technical Manual because of the design information security problem and the license cost. Therefore, various lightweight visualization formats and application systems have been suggested to overcome these problems. However, most of these lightweight formats are dependent on the companies or organizations which suggested them and cannot be shared with each other. In addition, product structure information is not represented along with the product geometric information. In this paper, we define a dataset called prod-X3D(Enhanced X3D Dataset for Web-based Visualization of 3D CAD Product Model) based on the international standard graphic format, X3D, which can represent the structure information as well as the geometry information of a product, and propose a translation method from 3D CAD data to an prod-X3D.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2019.05a
• /
• pp.248-249
• /
• 2019

In the nuclear industry, in order to keep pace with the 4th industrial revolution era, they are trying to improve the construction and maintenance ability by utilizing the technologies such as digital twin and VR/AR from the construction stage. However, the nuclear 3D CAD model, which is used as the base in the latest technology, is heavy due to a large number of facilities per unit space compared to other industrial companies, and it is difficult to directly incorporate the latest technology into the results of CAD programs for design purposes. In this study, in order to improve usability, we tried to lighten the 3D model. First, we analyze the existing nuclear power plant 3D model and draw out the problems and features. Secondly, we derived the factors to consider when we make the 3D CAD models lightweight.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.7 no.4
• /
• pp.550-553
• /
• 2006

This study used the 3D CAD/CAM system in manufacturing die plates to improve productivity. UG NX 3.0 was used as 3D CAD/CAM software, with the created NC code transmitted to the CNC Milling and Wire Cut Electric Discharge machine. The die plate was then automatically machined.

• Journal of Information Technology Applications and Management
• /
• v.20 no.3
• /
• pp.93-104
• /
• 2013

A 3D CAD is one of latest innovations in apparel industry. Despite a rapid progress of related technologies and an emergence of several commercial products in markets, an adoption of 3D CAD tools in apparel industry is much slower than originally expected. In an effort to diffuse such a technological advance in apparel industry, more behavioral studies of why and how apparel designers adopt and use a 3D CAD are needed. Toward that goal, this study aims to identify more about whether such an adoption decision would be more associated with organizations or individuals. Using TAM and TOE framework, the study findings show that the intention to adopt 3D garment CAD is more explained by individual attitudes rather than organizational characteristics.

• Journal of the Society of Naval Architects of Korea
• /
• v.43 no.3 s.147
• /
• pp.362-374
• /
• 2006

Currently, all design information of a hull structure is being first defined on 2D drawings not 3D CAD model at the initial ship design stage and then transferred to following design stages through the 2D drawings. This is caused by the past design practice, limitation on time, and lack of hull structural CAD systems supporting the initial design stage. As a result, the following design tasks such as the process planning and scheduling are being manually performed using the 2D drawings. For solving this problem, a data structure supporting the initial design stage is proposed and a prototype system is developed based on the data structure. The applicability of the system is demonstrated by applying it to various examples. The results show that the system can be effectively used for generating the 3D CAD model of the hull structure at the initial design stage.

• IE interfaces
• /
• v.24 no.1
• /
• pp.58-70
• /
• 2011

As more individuals and organizations participate in the complex design process of manufacturing industry, collaborative product development and management of the global supply chain have become more popular. Although the product quality concerns once focused on the manufacturing process, they are now directed at earlier stages of the design cycle where the engineering product is created as a 3D CAD model. In this paper, we describe the current state of product data quality activities in the manufacturing industry and the yardstick to measure 3D CAD data quality. Moreover we introduce a quality assurance method through the result of statistical analysis of 3D CAD models and suggest a six sigma level of CAD data quality by analyzing 76 samples provided from three Korean automotive companies.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2007.04a
• /
• pp.289-294
• /
• 2007

Virtual reality (VR) technology for construction project includes 3D CAD application and 4D CAD system for visualizing construction schedule data. 3D CAD application is more important in the design phase and 4D CAD system is effective tool in the construction phase. This study suggests a methodology to develop VR functions that can be used for project life cycle. The results of this study includes composition algorithms to make VR systems such as bird's eye view system, VR drawings system, VR telepresence system and VR risk management system. Those methodologies can be used for integrated VR system with nD CAD object.

• Journal of Fashion Business
• /
• v.17 no.1
• /
• pp.30-41
• /
• 2013

Augmented reality techniques have been increasingly employed in the textile and fashion industry as well as computer graphics sectors. Three-dimensional virtual clothing CAD systems have also been widely used in the textile industries and academic institutes. Motion tracking techniques are grafted together in the 3D and augmented reality techniques in order to develop the virtual three-dimensional clothing and fitting systems in the fashion and textile industry sectors. In this study, three-dimensional virtual clothing sample has been prepared using a 3D virtual clothing CAD along with a 3D scanning and reconstruction system. Motion of the user has been captured through an RGB-D sensor system, and the virtual clothing fitted on the user's body is allowed to move along with the captured motion flow of the user. Acutal fabric specimens are selected for the material characterization. This study is a primary step toward building a comprehensive system for the user to experience interactively virtual clothing under real environment.