• Journal of the Computational Structural Engineering Institute of Korea
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• v.22 no.5
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• pp.475-485
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• 2009

In this paper a two-step algorithm is proposed to efficiently generate rebar elements from 3D CAD data in the context of CAD/CAE data transfer. The first step is an algorithm to identify various type rebar objects and their attributes by analyzing 3D CAD data in STEP format, which is one of the international data standards. The second algorithmic step is a procedure to generate one-dimensional rebar elements from the object data made through the first step for finite element analysis or other CAE tasks. Successful rebar element data generation from real 3D CAD data for a reinforced concrete structure shows the efficacy of the proposed algorithm.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.10
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• pp.1075-1084
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• 2014

It is necessary to construct an equipment catalog in plant design. A different level of detail may be needed for the three-dimensional (3D) computer aided design (CAD) data for equipment, depending on the purpose. Equipment suppliers provide CAD data with high complexity, whereas plant designers need CAD data with low complexity. Therefore, it is necessary to simplify the 3D CAD assembly data. To resolve this issue, a system for automatically simplifying the 3D CAD assembly data of equipment was developed. This paper presents the architecture of the system, the detailed functions of the system, and a neutral data format used for uploading simplified 3D CAD assembly data to a plant 3D CAD system. In addition, experiment results using the prototype system are explained.

• Journal of Game and Entertainment
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• v.2 no.1
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• pp.64-70
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• 2006

CAD system is a very important technology in designing many products which we are using today. This CAD technology have enlarging its area into 3D CAD systems with the development of computer graphics technologies. In particular, such advances have also been realized in special area such as the CAD system for designing shoes. 3D CAD systems for shoes design must provide compatibility between 3D and 2D data because shoes are made using 2D parts of pieces of leather or cloth. Many designers get high performances using 2D shoe CAD systems because they have had long practices with the 2D systems. Therefore, to get the mapping between 2D modeling and 3D modeling is one of very important components in 3D CAD system. In this paper, we proposed a flattening method that convert 3D shoes data to 2D data.

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

• Journal of the Korean Geographical Society
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• v.41 no.2 s.113
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• pp.188-194
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• 2006

Three-dimensional topological data is essential for 3D modeling and application such as emergency management and 3D network analysis. This paper reviewed current 3D topological data model and developed a method to construct 3D topological node-relation data structure from 2D computer aided design (CAD) data. The method needed two steps with medial axis-transformation and topological node-relation algorithms. Using a medial-axis transformation algorithm, the first step is to extract skeleton from wall data that was drawn polygon or double line in a CAD data. The second step is to build a topological node-relation structure by converting rooms to nodes and the relations between rooms to links. So, links represent adjacency and connectivity between nodes (rooms). As a result, with the conversion method 3D topological data for micro-level sub-unit of each building can be easily constructed from CAD data that are commonly used to design a building as a blueprint.

• Journal of the Society of Naval Architects of Korea
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• v.35 no.4
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• pp.98-108
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• 1998

Hull design data is currently prepared by a 2D CAD system and re-input to 3D CAD systems specialized for detail design or to a structural analysis system. In this paper, sharing design data among different CAD systems has been studied. Based on STEP methodology, a neutral model is generated from 2D AutoCAD drawings. To handle a geometric data of this model, the non-manifold model of ACIS is used because it can support various CAD data representation such as 2D graphic entities, 3D wireframe, 3D surface model, and solid B-Rep/CSG model. It is observed that a mon-manifold model can easily be transformed to a 3-D wireframe model for the hull detail design system AutoDef or a FE model for the structural analysis system Nastran.

• Journal of Korea Multimedia Society
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• v.9 no.8
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• pp.1010-1019
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• 2006

CAD system is a very important technology in designing the products which we are using today. This CAD technology has been enlarging its area into 3D CAD systems with the development of computer graphics technologies. In particular, such advances have been realized in special area such as the CAD system for designing shoes. However, because it is difficult to design a 3D CAD system, most CAD developments except for major CAD software companies usually have employed the AutoCAD which realizes 3D concepts. Also, many shoes' designers have been skilled with 2D shoe CAD systems and then they can make high achievements. Therefore, we design a new shoe CAD system with advantages of 2D CAD system and 3D CAD system. We also implement the scheme to transfer the data between 2D CAD system and 3D CAD system and also grading technologies to get patterns of various shoes size from a basic shoe's design.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2004.05a
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• pp.395-400
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• 2004

This study is that STEP based Data Repository of APR1400 Nuclear Power Plant Reactor Coolant System is developed. The STEP based Data Repository is accessed by Web-based and an attribute data of Reactor Coolant System Equipment is offered. Also, a P&ID drawing file & 3D CAD Model of Reactor Coolant System is loaded. The P&ID drawing file of Reactor Coolant System Equipment Model is connected with 3D CAD Model file. This 2D/3D CAD Model connected Prototype system confirms a real layout of Reactor Coolant System.

• The monthly packaging world
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• s.101
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• pp.168-171
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• 2001

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.645-648
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• 2008

Due to the rapid increase super high-rise buildings and multi-complex spaces, the space of a staged a very complex and variety of situations occur in the space of the building. The management is still based on limited information obtained by the administrator depends on the decision is made. However, the ability of human beings during a limited time, analysis limited information, and there is a limit to take the appropriate action and situation. To overcome these limitations high information technology that can be fused to take advantage of ubiquitous system is to offer. The aim of this study is on object-oriented 3D data and collected information about the status of the 3D data extraction, to exchange data between systems, the use of object-oriented 3D data, and I studied common space information of a multi-use facilities extracted from 3D CAD information to send to the GIS system.