• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1143-1145
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• 2003

Some of satellites such as IKONOS don't provide the orbital elements so that we can’ utilize the physical sensor model. Therefore, Rational Function Model(RFM) which is one of mathematical models could be a feasible solution. In order to improve 3D geopositioning accuracy of IKONOS stereo imagery, Rational Polynomial Coefficients(RPCs) of the RFM need to be updated with Ground Control Points(GCPs). In this paper, a method to improve RPCs of RFM using GCPs and 3D cube is proposed. Firstly, the image coordinates of GCPs are observed. And then, using offset values and scale values of RPC provided, the image coordinates and ground coordinates of 3D cube are initially determined and updated RPCs are computed by the iterative least square method. The proposed method was implemented and analyzed in several cases: different numbers of 3D cube layers and GCPs. The experimental results showed that the proposed method improved the accuracy of RPCs in great amount.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.3 s.309
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• pp.68-75
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• 2006

In this paper, we propose an adaptive video watermarking method using human visual system(HVS) and characteristics of three-dimensional cosine transform (3D-DCT) cubes. We classify 3D-DCT cubes into three patterns according to the distribution of coefficients in the 3D-DCT cube: cube with motion and textures, cube with high textures and little motion, and cube with little textures and line motion. Images are also classified into three types according to the ratio of these patterns: images with motion and textures, images with high textures and little motion, and images with little textures and little motion. The proposed watermarking method adaptivelyinserts the watermark on the coefficients of the mid-range in the 3D-DCT cube using the appropriately learned sensitivity table and the proportional constants depending on the patterns of 3D-DCT cubes and types of images. Experimental results show that the proposed method achieves better performance in terms of invisibility and robustness than the previous method.

• Journal of Digital Contents Society
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• v.14 no.3
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• pp.381-390
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• 2013

Almost all the mobile phone users already moved or are now moving away to smartphones for their various applications like games. If we are to speak about game applications, due to the performance limits of smartphones, 2D games are predominant over 3D games in every app. store. In this paper, we implement a 3D cube game application by porting an existing visual c++ irrlicht cube application to android platform library using the android Native Development Kit. After the porting is done, we add a few new features for more fun. Because the android NDK makes the existing C/C++ codes run directly on the android operating systems, we found by real execution tests that our 3D cube app. is well executed on a low-end android smartphone without any performance problem.

• Journal of Aerospace System Engineering
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• v.8 no.3
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• pp.27-33
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• 2014

The CubeSat, which was first launched to verify new technologies and for educational purposes, is now widely used as an educational tool since it makes possible development of manpower through practical training to produce the satellite at low development costs. At present, research and development on the CubSat is rapidly expanding in domestic and foreign universities. As one of the final 3 teams selected in the 2013 CUBE SATELLITE CONTEST organized by the Ministry of Science, ICT and Future Planning, Chosun University is also currently conducting R & D of STEP Cube Lab, which is a CubeSat scheduled to be launched in 2015 and whose main task is to verify space-based technologies in orbit. The present paper tries to present an overview of the CubeSat of Chosun University whose development is being led by its undergraduate students, and further, introduce the strengths of the present development program for developing space experts, based on the educational achievements from the R & D.

• Journal of KIISE:Software and Applications
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• v.32 no.3
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• pp.173-180
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• 2005

This paper proposes an effective algorithm that combines both the stereo matching and the marching cube algorithm. By applying the stereo matching technique to an image obtained from various angles, 3D geometry data are acquired, and using the camera extrinsic parameter, the images are combined. After reconstructing the combined data into mesh using the image index, the normal vector equivalent to each point is obtained and the mesh smoothing is processed. This paper describes the successive processes and techniques on the 3D mesh reconstruction, and by proposing the intermediate iso- surface algorithm. Therefore it improves the 3D data instability problem caused when using the conventional marching cube algorithm.

• Journal of Korea Multimedia Society
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• v.20 no.8
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• pp.1224-1235
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• 2017

Recently, augmented reality technology has received much attention in many fields. This paper presents an augmented reality system using Rubiks' Cube which can augment various 3D objects depending on patterns of a Rubiks' cube. The system first detects a cube from an image using partitional clustering and strongly connected graph. Thereafter, the system detects the top side of the cube and finds a proper pattern to determine which object should be augmented. An object corresponding to the pattern is finally augmented according to the camera viewpoint. Experimental results show that the proposed system successfully augments various virtual objects in real time.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.6
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• pp.1333-1337
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• 2011

3D engines loading, and expansion of the usable capacity, next-generation smartphone game markets are rising briskly by the improvement in CPU processing speed of Phones (hardware of smartphone). Therefore, in creating 3D game characters, realistic and free-form animations in a small screen of a smartphone are becoming important. Through this paper, as a method of creating characters and operating for game characters to cause user's feeling, with NURBS data of MAYA, We completed a face in turns of eyes, a nose, and a mouth, and with Polygon Cube tool, modeled hands and feet. After dividing a cube into half and modeling it, through mirror copying We completed the whole body and modeled the low-polygon. Then to model realistic and free-form characters, We completed each detail with ZBrush and applied Divide level up to 4. Though they might look rough and exaggerated, We tried to express stuck-out parts and fallen-in parts effectively and smoothly with Smooth brush effect, map and design the low-polygon 3D characters.

• Journal of Korea Foundry Society
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• v.26 no.6
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• pp.272-276
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• 2006

For the first time AZ91 (MgAl9Zn1) and AM60 (MgAl6) Mg alloy foams with homogeneous pore structures were prepared successfully via melting foaming method by using $CaCO_3$ powder as blowing agent. The possible foaming mechanisms and pore structures of these Mg alloy foams were discussed and investigated. The results show that Mg alloy melt can affect $CaCO_3$ decomposition behavior and AZ91 Mg alloy is relative easy to be foamed into metal foam with high porosity and big pore size.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.300-303
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• 2011

Owing to the improvement in CPU processing speed of Phones (hardware of smartphone), 3D engines loading, and expansion of the usable capacity, next-generation smartphone game markets are rising briskly. Therefore, in creating 3D game characters, realistic and free-form animations in a small screen of a smartphone are becoming important. Through this paper, as a method of creating characters and operating for game characters to cause user's feeling, with NURBS data of MAYA, We completed a face in turns of eyes, a nose, and a mouth, and with Polygon Cube tool, modeled hands and feet. After dividing a cube into half and modeling it, through mirror copying We completed the whole body and modeled the low-polygon. Then to model realistic and free-form characters, We completed each detail with ZBrush and applied Divide level up to 4. Though they might look rough and exaggerated, We tried to express stuck-out parts and fallen-in parts effectively and smoothly with Smooth brush effect, map and design the low-polygon 3D characters.

• School Mathematics
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• v.18 no.2
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• pp.323-348
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• 2016

The 2009 revised national mathematics curriculum have inserted mathematical 'linking cube' activities in the 6th grade math classes to improve students' spatial problem solving abilities and communication skills. However, we found that it was hard for teachers to teach problem solving and communication skills due to the absence of mathematical way of representing linking cubes in the classroom. In this paper, we propose 3D 'turtle representation system' as teaching and learning tools for linking cube activities. After using turtle representation system for linking cube activities, teachers responded that turtle representation system is a valuable problem solving and communication tools for the linking cube mathematics classes. We conclude that turtle representation system is a well designed teaching and learning tools for linking cube activities, and there are lots of educational meanings in the 3D turtle representation system.