• Journal of Institute of Control, Robotics and Systems
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• v.21 no.11
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• pp.996-1002
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• 2015

In this paper, we present an effective system for the 3D scene labeling of objects from RGB-D videos. Our system uses a Markov Random Field (MRF) over a voxel representation of the 3D scene. In order to estimate the correct label of each voxel, the probabilistic graphical model integrates both scores from sliding window-based object detectors and also from object location prior maps. Both the object detectors and the location prior maps are pre-trained from manually labeled RGB-D images. Additionally, the model integrates the scores from considering the geometric constraints between adjacent voxels in the label estimation. We show excellent experimental results for the RGB-D Scenes Dataset built by the University of Washington, in which each indoor scene contains tabletop objects.

• Korean Journal of Computational Design and Engineering
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• v.9 no.4
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• pp.373-381
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• 2004

Using standard components of a press die is recognized as a way for a cost reduction and a short lead time. It also provides a way for a quick maintenance of a die under repair. It is expected to contribute to integration of CAD/CAM system for manufacturing dies in the future. This paper presents a 3D CAD library which is constructed using the standard components and is used for designing a press die. This 3D CAD library is generated by a database system made of Microsoft Access for standard components and by CATIA V5 R10 API for geometric features. The library is implemented using Visual Basic 6.0 utility of CATIA API function in the Windows NT environment. It creates a 3D model of the standard components of press die easily when a die designer inputs numerical values of geometric features and the BOM of the completely assembled parts. It also generates automatically the assembly drawing of die set by using variables for standard values of die parts. Therefore users can save the cost of time to design the press die components, and even a beginner can use this program with ease. The test results of the 3D CAD library for designing shearing and bending dies verify its usefulness and feasibility.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.292-295
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• 2002

In this paper, an analytical model for the prediction of the elastic properties of multi-axial warp knit fabric (MWK) composites is proposed. The geometric limitation, effect of stitching fibers and design parameters of MWK composites are considered in the model. The elastic behavior of MWK composites was conducted by using an averaging method. The predicted elastic properties are in reasonably good agreement with experimental values. Finally the effect of stitching in the MWK composites are discussed.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.3284-3306
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• 2018

This study proposes a method to develop an authoring system(GeoMaTree) for diverse trees that constitute a virtual landscape. The GeoMaTree system enables the simple, intuitive production of an efficient structure, and supports real-time processing. The core of the proposed system is a procedural modeling based on a mathematical model and an application that supports digital content creation on diverse platforms. The procedural modeling allows users to control the complex pattern of branch propagation through an intuitive process. The application is a multi-resolution 3D model that supports appropriate optimization for a tree structure. The application and a compatible function, with commercial tools for supporting the creation of realistic synthetic images and virtual landscapes, are implemented, and the proposed system is applied to a variety of 3D image content.

• Journal of the Korea Computer Graphics Society
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• v.28 no.4
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• pp.1-11
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• 2022

The Skinned Multi-Person Linear Model (SMPL) is the most widely used parametric 3D Human Model optimized and learned from CAESAR, a 3D human scanned database created with measurements from 3,800 people living in United States in the 1990s. We point out the lack of racial diversity of body types in SMPL and propose K-SMPL that better represents Korean 3D body shapes. To this end, we develop a fitting algorithm to estimate 2,773 Korean 3D body shapes from Korean body measurement data. By conducting principle component analysis to the estimated Korean body shapes, we construct K-SMPL model that can generate various Korean body shape in 3D. K-SMPL model allows to improve the fitting accuracy over SMPL with respect to the Korean body measurement data. K-SMPL model can be widely used for avatar generation and human shape fitting for Korean.

• Proceedings of the KSR Conference
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• 1998.11a
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• pp.601-607
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• 1998

This paper presents the efficient 2-D linear brake analysis model which can compensate the lateral leakage flux by changingng the airgap length and magneto-motive force(MMF). The linkage flux of the 2-D analysis is larger than that of 3-D analysis. This is caused by the assumption in 2-D analysis that geometric and physical values are constant along the perpendicular direction(z) to the analysis region. The equivalent MMF have been calculated from the linkage flux difference between the 2-D and 3-D analyses which are performed at zero velocity. The performances of the linear brake have been analyzed effectively by using the compensated 2-D models without using 3-D FEM.

• The Journal of Society for e-Business Studies
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• v.1 no.1
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• pp.141-157
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• 1996

Data sharing is a major challenge to implement CALS. STEP is the international standard for the product model data exchange among heterogeneous systems and plays a key role in CALS. Advances in computer networks are rapidly changing the product development processes. The network oriented modeling system premises to integrate design activities across the enterprise. To achieve goals of CALS 3-dimensional concurrent modeling that complies international standard is required since integrity and common perception of product data can be assured. This paper presents 3-dimensional concurrent geometric modeling on high speed network using STEP and methodologies.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.10a
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• pp.67-70
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• 2003

To develop an effective geometric modeling is essential in order that precise mechanical properties and the geometrical properties of the 3-D braided composites can be estimated. RVE(representative volume element) was adopted fur geometrical modeling. RVE consisted of IC(inner unit cell), ISUC(interior surface unit cell) and ESUC(exterior surface unit cell). The whole geometrical model fur hybrid 3-D braided composites was developed.

• Journal of the Korea Computer Graphics Society
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• v.3 no.2
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• pp.77-84
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• 1997

Solid modeling refers to techniques for unambiguous representations of three- dimensional objects. The most widely used techniques for solid modeling have been Constructive Solid Geometry (CSG) and Boundary Representation (BRep). Contemporary solid modeling systems typically support both representations, and bilateral conversions between CSG and BRep are essential. However, computing a CSG from a BRep is largely an open problem. This paper presents 3D geometric reasoning algorithms for converting a BRep into a special CSG, called Destructive Solid Geometry (DSG) whose Boolean operations are all subtractions. The major application area of BRep-to-DSG conversion is feature recognition, which is essential for integrating CAD and CAM.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1177-1179
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• 2003

Recently, the ground-based laser profiler is used for acquisition of 3D spatial information of a rchaeological objects. However, it is very difficult to measure complicated objects, because of a relatively low-resolution. On the other hand, texture mapping can be a solution to complement the low resolution, and to generate 3D model with higher fidelity. But, a huge cost is required for the construction of textured 3D model, because huge labor is demanded, and the work depends on editor's experiences and skills . Moreover, the accuracy of data would be lost during the editing works. In this research, using the laser profiler and a non-calibrated digital camera, a method is proposed for the automatic generation of 3D model by integrating these data. At first, region segmentation is applied to laser range data to extract geometric features of an object in the laser range data. Various information such as normal vectors of planes, distances from a sensor and a sun-direction are used in this processing. Next, an image segmentation is also applied to the digital camera images, which include the same object. Then, geometrical relations are determined by corresponding the features extracted in the laser range data and digital camera’ images. By projecting digital camera image onto the surface data reconstructed from laser range image, the 3D texture model was generated automatically.