• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.50.1-50.1
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• 2020

In this topic, I will introduce a recent work on reconstructing the cosmic density field based on the GAN. I will show the performance of the GAN compared to the traditional Unet architecture. I'd also like to discuss a 3-channels-based 2D datasets for the training to recover the 3D density field. Finally, I will present some performance tests based on the test datasets.

• Science of Emotion and Sensibility
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• v.20 no.2
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• pp.87-102
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• 2017

With increasing interest in 3D printing, the interest in the 3D modelling training that should precede the 3D printing is increasing. However, the existing 3D modelling software is developed mostly by foreign brands. Thus, the interfaces are all in English. 3D modelling software training for Korean novices who are not familiar with these terms has constraints. This study aims to explore what to consider when developing a Korean model for 3D modelling educational software for 3D printing in the face of such reality. For this goal, after having novices with no experience in 3D modeling to perform a house building task using either 12D Design or Tinker CAD, we conducted a survey. It was found in the result that more users favored Tinker CAD over 123D Design, and the errors involved while working with the Tinker CAD were less than those with the 123D Design, and the ratio of people who completed the task with the Tinker CAD was higher than that with the 123D Design. In general discussion, an introductory level educational 3D modeling software development is proposed which utilize characteristics of Tinker CAD (easy modelling is possible by three-dimensional figures) and web-based method. Also, a beginner/intermediate level educational 3D modeling software development is proposed which utilize characteristics of 123D Design (with finer measurement manipulations and figure alignment) and Windows-based method.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.511-512
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• 2002

A new stereoscopic PTV was developed using two CCD cameras, stereoscopic photogrammetry based on a 3D-PTV principle. The arrangement of the two cameras was based on angular position. The calibration of cameras and the pair-matching of the three-dimensional velocity vectors were based on Genetic Algorithm based 3D-PTV technique. The constructed Stereoscopic W technique was tested on the standard images of the impinged jet proposed by VSJ. The results on the turbulent properties of the jet obtained by the constructed system showed a good agreement with the original LES data.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.412-417
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• 2008

In a traditional topology optimization method, material properties are usually distributed by finite element density and visualized by a gray level image. The distribution method based on element density is adequate for a great mass of 2-D topology optimization problems. However, when it is used for 3-D topology optimization, it is always difficult to obtain a smooth model representation, and easily appears a virtualconnect phenomenon especially in a low-density domain. The 3-D structural topology optimization method has been developed using the node density instead of the element density that is based on SIMP (solid isotropic microstructure with penalization) algorithm. A computer code based on Matlab was written to validate the proposed method. When it was compared to the element density as design variable, this method could get a more uniform density distribution. To show the usefulness of this method, several typical examples of structure topology optimization are presented.

• Korean Journal of Computational Design and Engineering
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• v.12 no.4
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• pp.283-297
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• 2007

Seamless data integration in the CAx chain of the CAD/CAPP/CAM/CNC has been achieved to a high degree, but research concerning the transfer of data from conceptual sketches to a CAD system should be carried out further. This paper presents a method for reconstructing a 3D model from a freehand sketch. Sketch-based modeling research can be classified into gestural modeling methods and reconstructional modeling methods. This research involves the reconstructional modeling method. Here, Mitani's seminal work, designed for box-shaped 3D model using a predefined template, is improved by leveraging a relational template and specialized for automotive design. Matching between edge graphs of the relational template and the sketch is formulated and solved as the assignment problem using the feature vectors of the edges. Including the stroke preprocessing method required to generate an edge graph from a sketch, necessary procedures and relevant techniques for implementing the template-based modeling method are described. Examples from a working implementation are given.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.341-345
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• 2007

The objective of this paper is to introduce a project on developing construction method based estimation system. It means a 3D product model based estimation system to effectively and efficiently manage estimation process during the project life-cycle. This paper describes a outline and method for 3D based estimation system. Normally, it is not easy to take-off the quantity from 3D CAD model, because of all different depths of the quantity take off in each design development stage and nation. This study shows how to keep the balance of its depths in each design development stage such as schematic design, detail design, shop drawing, and so forth.

• Journal of International Society for Simulation Surgery
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• v.1 no.2
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• pp.57-61
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• 2014

We present a robust 3D facial reconstruction method using a single image generated by face-specific super resolution technique. Based on the several consecutive frames with low resolution, we generate a single high resolution image and a three dimensional facial model based on it. To do this, we apply PME method to compute patch similarities for SR after two-phase warping according to facial attributes. Based on the SRI, we extract facial features automatically and reconstruct 3D facial model with basis which selected adaptively according to facial statistical data less than a few seconds. Thereby, we can provide the facial image of various points of view which cannot be given by a single point of view of a camera.

• JSTS:Journal of Semiconductor Technology and Science
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• v.13 no.4
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• pp.318-330
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• 2013

This paper presents a high-linearity low-noise small-size programmable gain amplifier (PGA) based on a new low-noise low-distortion differential amplifier and a proposed reconfiguration technique. The proposed differential amplifier combines an inverter-based differential pair with an adaptive biasing circuit to reduce noise and distortion. The reconfiguration technique saves the chip size by half by utilizing the same differential pair for the input transconductance and load-stage, interchangeably. Fabricated in $0.18-{\mu}m$ CMOS, the proposed PGA shows a dB-linear control range of 21dB in 16 steps from -11 dB to 10 dB with a gain error of less than ${\pm}0.33$ dB, an IIP3 of 7.4~14.5 dBm, a P1dB of -7~1.2 dBm, a noise figure of 13dB, and a 3-dB bandwidth of 270MHz at the maximum gain, respectively. The PGA occupies a chip area of $0.04mm^2$ and consumes only 1.3 mA from the 1.8 V supply.

• Journal of Korea Multimedia Society
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• v.14 no.8
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• pp.1094-1107
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• 2011

We can use panorama systems or image based modeling systems when we want to make 3D space model and look around result. Panorama systems make 3D model to stitch images and map cylinder or cube. The structure of 3D model, made by panorama system, is not same as structure of a real room, so user can't infer a real structure. Typically, Image based modeling systems work on a desktop computer. That makes it difficult to reconstruct 3D model in real time and take long time for processing. In this paper, we propose a 3D panorama modeling system that uses images on a mobile device. This system reconstructs a 3D space model, similar with a real room in real time, from multiple images captured part of rooms. Using this system, user can reconstruct various shape of space and look around a 3D space model.

• Journal of Satellite, Information and Communications
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• v.10 no.1
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• pp.56-61
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• 2015

In this paper, the 3D positioning of IoT sensors with the Unity engine of android platform based home-hub was proposde for IoT(Internet of Things) users. Especially, the monitoring of IoT sensor and battery status was designed with the clustering of IoT sensor's position. The 3D positioning of RSSI(received signal strength indicator) and angle for new IoT sensor according to clustering method was described with the cooperation of beacon and received arrival signal time. This unity engine based smart hub platform can monitor the working situation of IoT sensors, and apply 3D video with texture for the life-cycling of many IoT sensors simultaneously. rs was described with RSSI(received signal strength indicator) and received angle.