• Journal of Electrical Engineering and Technology
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• v.13 no.6
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• pp.2530-2544
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• 2018

In this paper, we propose an enhanced LiDAR-camera calibration method that extracts the marker plane from 3D point cloud information. In previous work, we estimated the straight line of each board to obtain the vertex. However, the errors in the point information in relation to the z axis were not considered. These errors are caused by the effects of user selection on the board border. Because of the nature of LiDAR, the point information is separated in the horizontal direction, causing the approximated model of the straight line to be erroneous. In the proposed work, we obtain each vertex by estimating a rectangle from a plane rather than obtaining a point from each straight line in order to obtain a vertex more precisely than the previous study. The advantage of using planes is that it is easier to select the area, and the most point information on the board is available. We demonstrated through experiments that the proposed method could be used to obtain more accurate results compared to the performance of the previous method.

• Journal of Conservation Science
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• v.36 no.1
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• pp.37-46
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• 2020

It is difficult to predict the kinds of damage to contemporary art because of the diversity of materials and experimental techniques used. This makes it hard to conserve. Furthermore, the artist's intention in contemporary art is emerging as one of the important issues to be handled in conservation treatment. Thus, collaboration with various stakeholders such as the artists themselves, bereaved family members, and foundations have become more important than ever from the viewpoint of planning conservation treatment. The trustworthiness of conservation treatment would be significantly enhanced if conservation treatment reflected the understanding and respect of not only the appearance of the work, but also the social/cultural context inherent in the work. This should be done, in particular, through collaboration with the artists. In this study, various case studies at home and abroad were analyzed as to explore collaboration methods with various stakeholders for objective and trustworthy conservation treatment. Along the way, the study raised the need to establish new conservation ethics for contemporary art. It is expected that the outcomes of the study could be used as basic material to preserve the originality of contemporary artwork and to set the direction for conservation practice.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.1
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• pp.91-98
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• 2017

Performance of a low speed axial compressor is enhanced through a proper configuration of blade row tip injection and casing treatment of groove type. Air injectors were mounted evenly spaced upstream of the blade row within the casing groove and were all aligned parallel to the compressor axis. The groove, which covers all the blade tip chord length, extends all-round the casing circumference. Method of investigation is based on solution of the unsteady form of the Navier-Stokes equations utilizing $k-{\omega}$ SST turbulence model. Extensive parametric studies have been carried out to explore effects of injectors' flow momentums and yaw angles on compressor performance, while being run at different throttle valve setting. Emphasis has been focused on situations near to stall condition. Unsteady numerical analyses for untreated casing and no-injection case for near stall condition provided to discover two well-known criteria for spike stall inception, i.e., blade leading edge spillage and trailing edge back-flow. Final results showed that with only 6 injectors mounted axially in the casing groove and at yaw angle of 15 degrees opposite the direction of the blade row rotation, with a total mass flow rate of only 0.5% of the compressor main flow, surprisingly, the stall margin improves by 15.5%.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.8
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• pp.752-759
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• 2008

In this paper, we propose a high accurate geo-location system based on a single base station, where its location is obtained by Time-of-Arrival(ToA) and Direction-of-Arrival(DoA) of the radio signal. For estimating accurate ToA and DoA information, a MUltiple SIgnal Classification(MUSIC) is adopted. However, the estimation of ToA and DoA using MUSIC algorithm is a time-consuming process. The position tracking bias is occurred by the time delay caused by the estimation process. In order to mitigate the bias error, we propose the estimation method of the position tracking bias and compensate the location error produced by the time delay using the position tracking bias mitigation. For accurate self-localization of mobile robot, the Unscented Kalman Filter(UKF) with position tracking bias is applied. The simulation results show the efficiency and accuracy of the proposed geo-location system and the enhanced performance when the Unscented Kalman Filter is adopted for mobile robot application.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.378-381
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• 2009

A rotating stall, an instable phenomenon of compressor, brings about reducing the pressure rise, the efficiency of compressor and a mechanical demage. In order to improve instability and extend operating range, it was performed that a stability enhancement experiment applying air injection method at the 4-stage low-speed axial compressor. The coanda nozzle was used to inject air in axial direction at rotor tip and 8 injectors were set up at regular interval at the upstream of 1st stage rotor. At 80% speed, injectors were worked before rotating stall happened. As injecting the 5.4% air of mode inception flow rate, the stability of compressor operation enhanced about 4%.

• Carbon letters
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• v.12 no.4
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• pp.185-193
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• 2011

Carbon nanotubes (CNTs) have developed into one of the most competitively researched nano-materials of this decade because of their structural uniqueness and excellent physical properties such as nanoscale one dimensionality, high aspect ratio, high mechanical strength, thermal conductivity and excellent electrical conductivity. Mass production and structure control of CNTs are key factors for a feasible CNT industry. Water and ethanol vapor enhance the catalytic activity for massive growth of vertically aligned CNTs. A shower system for gas flow improves the growth of vertically aligned single walled CNTs (SWCNTs) by controlling the gas flow direction. Delivery of gases from the top of the nanotubes enables direct and precise supply of carbon source and water vapor to the catalysts. High quality vertically aligned SWCNTs synthesized using plasma enhance the chemical vapor deposition technique on substrate with suitable metal catalyst particles. This review provides an introduction to the concept of the growth of vertically aligned SWCNTs and covers advanced topics on the controlled synthesis of vertically aligned SWCNTs.

• Journal of Broadcast Engineering
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• v.14 no.6
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• pp.742-748
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• 2009

Most commercial digital still cameras use a single sensor array (e.g., CMOS or CCD) with color filter array (CFA) to reduce the cost and size. Since the image obtained with CFA has only one color value per pixel, the demosaicing is needed to acquire missing two color values. Although many demosaicing methods have been proposed, they still have artifacts such as rainbow and zippering artifact. In this paper, we propose the simple demosaicing algorithm using tendency of neighbor pixels with the enhanced weighting function. In the experimental results, our algorithm shows much better subjective qualities of the images than conventional demosaicing algorithm and improves objective qualities.

• Fashion & Textile Research Journal
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• v.10 no.4
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• pp.464-472
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• 2008

Wearable computer focuses on functional aspects of fashion to respond to and satisfy needs for daily availability of ubiquitous environment owing to ever-developing digital technologies. The purpose of this study is to examine in possible developmental direction of wearable computer and thereby explore more promising directions of wearable computer to enhance its adaptability to future advanced ubiquitous environment and also satisfy both esthetical and functional needs. Now the wearable computer can be classified broadly into 3 types in the aspect of functionality, i.e. computer containing 'integratability', 'convertibility' and 'interactability'. Beyond simple portability concepts based on digital devices attached on body, it will be necessary that follow-up studies on wearable computer satisfy needs for enhanced digital functionality to comply with ubiquitous environment as well as emotional needs inherent in clothing. It is expected that possibility of future wearable computer will be extended via collaborative relationships between design and functionality, and should be implemented through possible points of contact among computer, telecommunication, design and fashion. Based on the findings of this study, it is expected that follow-up researches and developments for wearable computer to meet both functionality and esthetical values in the aspect of 'fashion design combined with electronic products' will help assure the variety of fashion designs for wearable computer contributing to better life quality of human in future ubiquitous environment.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.611-616
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• 2003

Through the whole period of the twentieth century, Chinese Traditional Medicine has been affected by the political and cultural changes of Chinese society. Before the 1949 Communist Revolution, Chinese Traditional Medicine was regarded as a dark past which should be cleared off. But Chinese Traditional Medicine has been reevaluated as a national medicine and spreaded quickly since the 1949 Communist Revolution. Moreover, 'the bare foot doctor' who received short term training appeared during the Cultural Revolution. It enhanced the status of Chinese Traditional Medicine. At the same time, it was estimated as a model of the self-reliant development of Third World countries. But the direction of development of Chinese Traditional Medicine was changed again recently. Chinese government has adapted the open-economy policy since the late 1970s. Accordingly Chinese Traditional Medicine also has been changed. Nowadays it pursues the professional development strategy. This paper inquired the following research questions. First, what kind of historical changes in the development strategy of Chinese Traditional Medicine has happened? Second, how much Chinese Traditional Medicine has accomplished the professionalization? Third, what kind of problems Chinese Traditional Medicine has met in the process of professionalization? Finally, why Chinese Traditional Medicine has adapted the professional development strategy?

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.356-358
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• 2002

MRI, particularly diffusion weighted imaging (DWI), plays vital roles in detection of the acute brain infarction$\^$1-4/ and others metabolic changes of biological tissues. In general, every molecule in biological tissues may diffuse and move randomly in three-dimensional space. However, in clinical diagnosis, only 2D-DWI is used. The authors have developed a new method for rapid three-dimensional DWI (3D-DWI). In this method, by refocusing of the magnetized spin with the applied gradient field, direction of which is opposite to phase encoding field. Magnetized spin of $^1$H is kept under the SSFP (steady state free precession)$\^$5-6/. Under SSFP, in addition of FID, spin echo and stimulated echo are also generated, so the acquired signal is increased. The signal intensity is increased depending on flip angle (FA) of magnetized spin. This phenomenon is confirmed by human brain and phantom studies. The performance of this method is quantitatively analyzed by using both of conventional spin echo DWI and 3D-DWI. From experimental results, three dimensional diffusion weighted images are obtained correctly for liquid phantoms (water, acetone and oil), diffusion coefficient is enhanced in each image. Therefore, this method will provide useful information for clinical diagnosis.