• Journal of the Society of Naval Architects of Korea
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• v.54 no.4
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• pp.344-351
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• 2017

CAD systems used in various manufacturing industries have been rapidly switched from 2D to 3D. 3D-based design is becoming common in the shipbuilding industries too. However, there is still a demand for 2D drawings for ship production. So, it is necessary to continually improve 2D drawings. One way to improve 2D drawings is to add production information to the drawings. To do this, it is necessary to define the relation between the geometry information and the production information. Various types of drawings, which is inevitable because each drawing has its own purpose, make it difficult to define relations. This process can be simplified if the drawing information is neutralized. XML is a standard format for defining neutral data, and is already being used in various fields. In this study, a neutral augmented drawing has been defined by neutralizing the drawing information based on XML, and implemented for the allocation of their information with high quality of readability as well.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.1132-1135
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• 2004

Recently. our construction industry is using 4D-CAD system but the public Database (DB) for the 4D-CAD system is insufficiently built. It is difficult to connect 4D-CAD system information such as schedule, drawings. Therefore this study suggest a methodology to link the 4D-CAD system information with work breakdown structure(WBS) and the methodology suggested in this study was applied to a 4D-CAD system

• Korean Journal of Construction Engineering and Management
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• v.16 no.4
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• pp.30-40
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• 2015

Two-dimensional drawings are widely used as a communication tool in the construction industry, but they are still hard to be understood by engineers with less experience. A four dimensional CAD drawing is presented based on marker-based augmented reality, for visual assistance, detailed information, and prevention of misunderstanding among users. The developed drawing enables the users to easily understand its contents through the functions augmenting components, providing detailed construction information, and simulating construction process, using the marker in a 2D drawing. A questionnaire-based survey validates the capability of the developed drawing that it improves inexperienced engineers' understanding of the drawings.

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

• Land and Housing Review
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• v.11 no.3
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• pp.93-101
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• 2020

Recently, as a BIM-based construction simulation system, 4D CAD tools using virtual reality (VR) objects are being applied in construction project. In such a system, since the expression of the object is based on VR image, it has a sense of separation from the real environment, thus limiting the use of field engineers. For this reason, there are increasing cases of applying augmented reality (AR) technology to reduce the sense of separation from the field and express realistic VR objects. This study attempts to develop a methodology and BIM module for the pre-construction verification system using AR technology to increase the practical utility of VR-based BIM objects. To this end, authors develop an AR-based drawing verification function and drawing object-based 4D model augmentation function that can increase the practical utility of 2D drawings, and verify the applicability of the system by performing case analysis. Since VR object-based image has a problem of low realism to field engineers, the linking technology between AR object and 4D model is expected to contribute to the expansion of the use of 4D CADsystem in the construction project.

• Korean Journal of Computational Design and Engineering
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• v.10 no.4
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• pp.244-253
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• 2005

In the initial ship design stage of shipyards, the hull form design, the basic design (compartment modeling and ship calculation), and the hull structural design are being performed by different systems. Thus, the problem on interfaces between these systems occurs. To solve this, we developed the hull form design system 'EzHULL' and the compartment modeling and ship calculation system 'EzCOM-PART' for developing finally an integrated ship design system. And, in this study, we present an object-oriented hull structural design .system 'EzSTRUCT', which is developed recently. A structural design in an initial design stage can be frequently changed, because the design is not firmly determined yet. Therefore, designers perform the simplified structural modeling with bigger structural parts (or objects) such as deck, longitudinal bulkhead, etc. in the initial design stage, and the detailed structural modeling with smaller structural parts such as plate, seam, slot, etc. in the detailed design stage. However, the existing hull structural CAD system used in a shipyard is not efficient in generating a 3D CAD model in the initial design stage, because it has difficulty in handling frequent changes in design. Therefore, designers initially draw 2D drawings in the initial design stage, and generate the 3D CAD model from these 2D drawings in the detailed design and production design stages. In this study, the hull structural design system, which can efficiently generate a 3D CAD model through rapid modeling at an initial design stage, was developed in this study To evaluate the applicability of the developed system, we applied it to hull structural modeling of various ships such as a VLCC, a bulk carrier, etc. As a result, it could efficiently generate a 3D CAD model of a hull structure.

• 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.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.515-519
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• 2005

Most information within a construction project roots in drawings and contract documents. Although several methodologies, such as A/E/C and 4D, have employed such a peculiarity to integrate project information, they failed to integrate information in terms of efficiency and consistency. In this research, a MD (Multi-Dimensional) CAD model is developed to improve the process of integrating information for construction projects. This research describes the processes of creating MD CAD objects and embedding information required throughout the project life cycle within MD CAD building components. In addition, a case study is presented to show the efficiency and effectiveness of using MDIIS (Multi-Dimensional Information Integration System) to integrate information for construction projects.

• Journal of the Korea Institute of Building Construction
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• v.16 no.2
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• pp.169-175
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• 2016

A survey of small-size contractors in Jeju was conducted to investigate college graduate's CAD (computer aided design) competence. Most of small-size contractors use CAD softwares to review and update drawings submitted from an architect. This research analyzed the curriculum of the architectural engineering in several national universities. The CAD classes have 4 or 6 hours per week and use AutoCAD primarily. This research proposes that a CAD class needs at least 6 hours per week, 2D drawing is the main theme in the curriculum, and exercises to make 3D models are also included in the CAD class. The improved methods, Internet cafe and real time feedbacks using a smartphone, to evaluate the reports and exercise results are necessary.

• Journal of Korean Institute of Industrial Engineers
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• v.20 no.3
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• pp.35-53
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• 1994

Orthographic views ore traditionally used for engineering drawings. This paper presents a methodology for 3D parametric design using orthographic views. The parametric design technique, which is used to design 2D orthographic views, is based on production rules. In the production rule-base, several view interrelation rules and over 50 geometric rules are included. An efficient algorithm is also developed to expedite the reasoning process. For 3D object construction from orthographic views, the approach known as bottom-up geometrical approach is used. The approach consists of 4 steps : 1) generation of wire-frame, 2) construction of face from wire frame, 3) formation of 3D subobjects from faces, and 4) construction of final 3D objects. Curvilinear solids as well as planar solids can be constructed. A method of converting existing 2D CAD data to parametric 3D CAD data is also presented.