• ETRI Journal
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• v.34 no.5
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• pp.734-742
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• 2012

A novel interaction method for mobile phones using their built-in cameras is presented. By estimating the path connecting the center points of frames captured by the camera phone, objects of interest can be easily extracted and recognized. To estimate the movement of the mobile phone, corners and corresponding Speeded-Up Robust Features descriptors are used to calculate the spatial transformation parameters between the previous and current frames. These parameters are then used to recalculate the locations of the center points in the previous frame into the current frame. The experiment results obtained from real image sequences show that the proposed system is efficient, flexible, and able to provide accurate and stable results.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.4
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• pp.1024-1040
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• 2014

The theoretical background and a numerical solution procedure for a time domain hydroelastic code are presented in this paper. The code combines a VOF-based free surface flow solver with a flexible body motion solver where the body linear elastic deformation is described by a modal superposition of dry mode shapes expressed in a local floating frame of reference. These mode shapes can be obtained from any finite element code. The floating frame undergoes a pseudo rigid-body motion which allows for a large rigid body translation and rotation and fully preserves the coupling with the local structural deformation. The formulation relies on the ability of the flow solver to provide the total fluid action on the body including e.g. the viscous forces, hydrostatic and hydrodynamic forces, slamming forces and the fluid damping. A numerical simulation of a flexible barge is provided and compared to experiments to show that the VOF-based flow solver has this ability and the code has the potential to predict the global hydroelastic responses accurately.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.12
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• pp.2298-2305
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• 1992

To obtain the convenient solution of the multibody dynamic systems composed of flexible beams, linear finite element technique is adopted and the nodal coordinates are interpolated in the global inertia frame. Mass matrix becomes an extremely simple constant matrix and the force vector also becomes extremely simple because Coriolis acceleration and centrifugal force are not required. And the elastic force is also simply computed from the moving frame attached to the material. To solve the global differential algebraic euation. an ODE technique is adopted after Lagrange multiplier is computed by the accelerated iterative technique, and the time demanding procedures such as Newton-Raphson iterations and decomposition of the big matrix are not required. The accuracy of the present solution is checked by a well-known example problem.

• Journal of Mechanical Science and Technology
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• v.17 no.1
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• pp.77-84
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• 2003

Virtual work in multibody systems is frequently expressed as the inner product of the virtual displacement and the resultant force at the centroid. But provided that the resultant force is converted into the equipollent forces there is no restriction on where the analysis reference point is placed. There are basically three candidate points : the centroid, joint point and the instant global origin. The traditional fully recursive formulation uses the centroid, but the present work verifies that the instant global origin always shows better efficiency (e.g. 86% CPU time of the centroid for quarter car model) and joint point shows the efficiency between that of the centroid and the instant global origin. A discussion on how important it is to define the analysis reference point properly in a fully recursive formulation is also presented.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1998.06b
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• pp.16.2-21
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• 1998

Old movies are often corrupted by randomly located blotches and scratches. In this paper were present an efficient method for detection and removal of these distortions. The presented method is composed of two separate steps: the detection process and the restoration process. In the detection process, blotch locations are detected through global motion segmentation, the sequential approach to motion segmentation, a robust model-fit criterion and so on, we form the algorithm for the algorithm for the global motion segmentation tuned to the blotch detection problem. In the restoration process, the missing data of the detected blotch areas are temporally extrapolated from the corresponding image areas at the preceding or the succeeding image frame with considering the global motion segmentation results. We apply the presented method to moving image sequences distorted by artificial blotches. The method works very well and provides a subjective improvement of picture quality.

• Journal of Korea Multimedia Society
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• v.22 no.4
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• pp.417-423
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• 2019

This paper presents an evaluation system to determine the completeness of a space map obtained by a visual SLAM(Simultaneous Localization And Mapping) algorithm. The proposed system consists of three parts. First, the proposed system detects the occurrence of loop closing to confirm that users acquired the information from all directions. Thereafter, the acquired map is divided with regular intervals and is verified whether each area has enough map points to successfully estimate users' position. Finally, to check the effectiveness of each map point, the system checks whether the map points are identifiable even at the location where there is a large distance difference from the acquisition position. Experimental results show that space maps whose completeness is proven by the proposed system has higher stability and accuracy in terms of position estimation than other maps that are not proven.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.52.2-52.2
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• 2019

Global map of solar surface magnetic field, such as the synoptic map or daily synchronic frame, does not tell us real-time information about the far side of the Sun. A deep-learning technique based on Conditional Generative Adversarial Network (cGAN) is used to generate farside magnetograms from EUVI $304{\AA}$ of STEREO spacecrafts by training SDO spacecraft's data pairs of HMI and AIA $304{\AA}$. Farside(or backside) data of daily synchronic frames are replaced by the Ai-generated magnetograms. The new type of data is used to calculate the Potential Field Source Surface (PFSS) model. We compare the results of the global field with observations as well as those of the conventional method. We will discuss advantage and disadvantage of the new method and future works.

• Journal of the Korean earth science society
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• v.40 no.3
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• pp.283-299
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• 2019

The purpose of this study is to identify the conflict frames in the process of designating the national geopark, among local residents, geology experts, and local public officials. For this purpose, the progress of the public hearing on the implementation of the national geopark in Buan and Gochang were recorded with prior consent from the participants and transferred in text form. Subsequently, we developed a reference frames for analyzing conflict frames through literature review, and analyzed the conflict frames by three researchers based on this. These analyzed conflict frames were again analyzed by using semantic network analysis. The results are as follows. In the Buan area, 'Sagree' frame, 'Snot' frame, and 'Sdisagree' frame showed high eigenvector centrality, and 'Gharm' frame and 'Cmeconomy' frame were closely connected to the 'Snot' frame located at the center of the semantic network. In the Gochang area, 'Aresource' frame, 'Cmexample' frame, and 'Gharm' frame showed high eigenvector centrality, and 'Gharm' frame and 'Cmproblemsolution' frame were closely connected to the 'Snot' frame located at the center of the semantic network. Through these results, we could see that there is still the conflict about the certification of national geopark between stakeholders in Buan, and that Gochang's stakeholders are proudly aware of their own resources. The Buan's stakeholders focused on economic gains in resolving conflicts, while Gochang's stakeholders focused on problem solving. This result of this study provides information in conflict from the national geopark in other regions.

• International Commerce and Information Review
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• v.10 no.2
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• pp.89-114
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• 2008

It is said that global business education in Korea must be a kind of good investment on the future of Korea, because Korea's degree of dependence upon global trade is very high. But, despite great significance of trade in economic aspect, education system on global business in Korea still remains in old paradigm focused mainly on trade in goods. The purpose of this paper is to analyse key environment of trade in Korea relating to global business education system, and to suggest some trade-friendly measures to improve the global economic environment being worse. Methodology used in this study depends on descriptive analysis by literature study. As all the paradigm of global business has shifted from 20C's trade environment to that of 21C's and still more borderless trend has progressed, it is high time Korea to design the new education system of global business to conform with the trade mode of Korea, and to execute the mode of strategic trade which is new conception of trade strategy derived from Web 2.0 trend. Major findings of this study can be summarized as follows : It is suggested that Korea should convert basic composition of trade strategy to strategic trade irrespective of company size, nationality, public or private sector, etc., and launch new instructional model considering the trade 2.0 concepts. Also, Korea's trade policies which have been based on 'trade in goods' should be changed to the frame of strategic trade so that can include various trade process such as trade in services, trade in technology, cultural contents, global investment(TRIMs), TRIPS, etc.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.2
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• pp.164-173
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• 2013

In this paper, we propose multi-frame based super resolution algorithm by using motion vector normalization and edge pattern analysis. Existing algorithms have constraints of sub-pixel motion and global translation between frames. Thus, applying of algorithms is limited. And single-frame based super resolution algorithm by using discrete wavelet transform which robust to these problems is proposed but it has another problem that quantity of information for interpolation is limited. To solve these problems, we propose motion vector normalization and edge pattern analysis for 2*2 block motion estimation. The experimental results show that the proposed algorithm has better performance than other conventional algorithms.