• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.12
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• pp.1356-1363
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• 2009

The aim of this research is to construct eigenfrequency optimization codes for plates with Arbitrary Rank Microstructures. From among noise factors, resonance sound is main reason for floor's solid noise. But, Resonance-elusion design codes are not fixed so far. Besides, The prediction of composite material's capability and an resonance elusion by controlling natural frequency of plate depend on designer's experiences. In this paper, First, using computer program with arbitrary rank microstructure, variation on composite material properties is studied, and then natural frequency control is performed by plate topology optimization method. The results of this study are as followed. 1) Programs that calculate material properties along it's microstructure composition and control natural frequency on composite material plate are coded by Homogenization and Topology Optimization method. and it is examined by example problem. 2) Equivalent material properties, calculated by program, are examined for natural frequency. In this paper, Suggested programs are coded using $Matlab^{TM}$, Feapmax and Feap Library with Homogenization and Topology Optimization method. and Adequacy of them is reviewed by performing the maximization or minimization of natural frequency for plates with isotropic or anisotropic materials. Since the programs has been designed for widely use. If the mechanism between composite material and other structural member is identified, extension application may be possible in field of structure maintenance, reinforcement etc. through application of composite material.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.8
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• pp.575-582
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• 2015

This paper deals with the dispersion relation of the waves sustained in a cylindrical shell submerged in the fluid. The waveguide finite method and the boundary element method are used to predict the dispersion characteristic of the cylindrical shell. The dispersion diagram of the cylinder is estimated from the eigenvalue problem and the forced vibration response. It follows that the water-loading leads to the decrease of the cut-on frequencies and the phase speeds of the bending waves. On the contrary, the longitudinal waves and the torsional waves are hardly affected by the fluid, and therefore the order of the cut-on frequencies of the waves is changed. The acoustic dispersion diagram is also estimated from the forced acoustic response to identify the characteristics of the wave radiated to the fluid. It follows that the acoustic waves on and near the surface of the cylinder are the same as those in the structure. But at the far field the acoustic waves caused by subsonic waves e.g., the bending waves disappear as the increase of the distance. Conclusively, the characteristics of waves in cylindrical shells are significantly affected by water-loading in terms of the cut-on frequency, the wave speed, the order of the cut-on and radiation.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.48-48
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• 2011

We have developed a chemically-driven top-down approach using vapor phase HCl to form various GaN nanostructures and successfully demonstrated dislocation-free and strain-relaxed GaN nanostructures without etching damage formed by a selective dissociation method. Our approach overcomes many limitations encountered in previous approaches. There is no need to make a pattern, complicated process, and expensive equipment, but it produces a high-quality nanostructure over a large area at low cost. As far as we know, this is the first time that various types of high-quality GaN nanostructures, such as dot, cone, and rod, could be formed by a chemical method without the use of a mask or pattern, especially on the Ga-polar GaN. It is well known that the Ga-polar GaN is difficult to etch by the common chemical wet etching method because of the chemical stability of GaN. Our chemically driven GaN nanostructures show excellent structure and optical properties. The formed nanostructure had various facets depending on the etching conditions and showed a high crystal quality due to the removal of defects, such as dislocations. These structure properties derived excellent optical performance of the GaN nanostructure. The GaN nanostructure had increased internal and external quantum efficiency due to increased light extraction, reduced strain, and improved crystal quality. The chemically driven GaN nanostructure shows promise in applications such as efficient light-emitting diodes, field emitters, and sensors.

• The Journal of Korea Robotics Society
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• v.11 no.4
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• pp.262-269
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• 2016

Flight of an autonomous unmanned aerial vehicle (UAV) generally consists of four steps; take-off, ascent, descent, and finally landing. Among them, autonomous landing is a challenging task due to high risks and reliability problem. In case the landing site where the UAV is supposed to land is moving or oscillating, the situation becomes more unpredictable and it is far more difficult than landing on a stationary site. For these reasons, the accurate and precise control is required for an autonomous landing system of a UAV on top of a moving vehicle which is rolling or oscillating while moving. In this paper, a vision-only based landing algorithm using dynamic gimbal control is proposed. The conventional camera systems which are applied to the previous studies are fixed as downward facing or forward facing. The main disadvantage of these system is a narrow field of view (FOV). By controlling the gimbal to track the target dynamically, this problem can be ameliorated. Furthermore, the system helps the UAV follow the target faster than using only a fixed camera. With the artificial tag on a landing pad, the relative position and orientation of the UAV are acquired, and those estimated poses are used for gimbal control and UAV control for safe and stable landing on a moving vehicle. The outdoor experimental results show that this vision-based algorithm performs fairly well and can be applied to real situations.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.1
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• pp.65-71
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• 2006

We examined the relationship between the basic characteristics and types of leisure activities according to blood types. It was based on questionnaires answered by 441 collegians in public health departments and 282 in non-public health departments in Daegu Health College in March, 2005. The frequency of leisure activity of once or twice a week or less during weekdays was the most common.: The most common frequencies for all blood types were between 1 and 2 hours on weekdays and between 3 and 5 hours on the weekends or holidays. As far as the type of leisure activities during the weekdays was concerned, in the case of public health departments, blood type A was interested in computer games and then watching TV, blood type B was attracted to watching TV and listening to music, blood type AB was into watching TV, computer games, and listening to music, and blood type O was keen on watching TV and computer games in that order. The type of leisure activity according to blood types in public health departments was shown to be significantly different (p<0.05). The type of future leisure activity was shown to be significantly different between public health departments and non-public health departments (p<0.05). The type of present leisure activity preferred by collegians, according to the study, was entertainment such as computer games for most blood types. The type of future leisure activities was related to the field of tourism and sports. The collegians need to have more advanced and positive leisure activities.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.8 s.145
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• pp.1057-1067
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• 2005

In the modem society, people try to represent and protect their traditional arts in aesthetic way along with the global society. The proposal of this thesis is about the fashion illustration that has adopted the folklike formative arts. 1 prefer the formative character rather then the universal character and I would like to use of folk paintings far the fashion illustration. Because the formative character of folk paintings is very expressional, we are able to draw a fashion illustration in easy, new, creative and less difficult way. The fashion illustration has to be a specialized field from the formative arts, and we need to study in a new way as well. We draw fashion illustration through the understanding of folk paintings and the study of analysis in formative. As a result of this study, we could draw a fashion illustration which is very abstract, exaggerative and simple. We also could expect the free hand drawing lines on this illustration. In these fashion illustrations, the human bodies let us fret the artists' tense, speed, and power. According to the important character of folk painting, which is the beauty of color, these fashion illustrations have expressed more color intensive. In the falk paintings there is a kind of rules to make color order, so the fashion illustrations that we drew have the bright and clear color combination. Because the folk paintings shouldn't be the artistic but should be the realistic, the fashion illustrations concentrate on the real subject. It is very natural looking that use the natural dyes in the fashion illustrations. According to this kind of art task, fashion illustration will be a certain part of the illustration in the modem society.

• Economic and Environmental Geology
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• v.36 no.4
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• pp.269-274
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• 2003

This study, one of the projects for investigation of the precious metal deposits of the Circum-Pacific Ocean coon-tries, was performed in a gem field of Pailling, Cambodia, in which there are numbers of undeveloped mineral resources. The gem fields in the Pailling area are typically distributed in the laterite, lying on of weathered basalts. The gem grade of corundum is low in the surface soil horizon(less than 1 m in depth), but is higher in the subsurface. Occurrence and genetic environment of the precious stone are not concerned in the soils. A Precious stone that is already made from at the least upper part of volcanic rocks is produced in large quantities to undergoing to weathering of the rocks. A precious stone is made from upper part of the formation under the high temperature when volcano is vomiting or after vomiting. and/or made from between the formation under the high temperature when other volcano is vomiting. Volcanic rocks including precious stone are a little different from other volcanic rocks when volcano is vomiting, but chemical composition of rocks is not far different from other volcanic rocks.

• Journal of Information Management
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• v.42 no.3
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• pp.147-165
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• 2011

This paper presents a core meta-tag of OpenURL written in Key/Encoded-Value format in the field of observation research, to distribute the scientific data, produced in many experimentations and observations, on the OpenURL service architecture. So far, the OpenURL hasn't supplied a meta-tag represented scientific data because it has focused on circulation of scholarly and technological information extracted from thesis, proceedings, journals, literatures, etc. The DataCite consortium metadata were analyzed and compared with the Dublin Core metadata, OECD metadata, and Directory Interchange Format metadata to develop a core meta-tag in observation research.

• Human Ecology Research
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• v.53 no.1
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• pp.93-106
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• 2015

The purpose of this study is to understand what we have learnt thus far on the sustainable consumption of natural resources by household in Korea. We propose a two-wing model designating households as the main agent of sustainable living where both the production of human resources and the consumption of natural resources take place. In the current study, we focused on the sustainability of natural resource consumption. Undertaking an empirical study, we selected 10 major journals that represent each area of human ecological research and then, identified 120 relevant studies regarding sustainability published since 2000. First, we classified 381 keywords into three categories: production, consumption, and social environment, and the identified studies were then classified in one of the seven categories created by combinations of the abovementioned three categories: production (P), consumption (C), social environment (S), production-consumption (PC), production-social environment (PS), consumption-social environment (CS), and production-consumption-social environment (PCS). The results showed that the sustainability of natural resources has been mainly investigated in the fields of clothing & textiles and food & nutrition. Further, consumer science research has been conducted in the area of consumption-social environment and consumption-production. The current study indicates that the field of human ecology has created and accumulated knowledge to support sustainable living. In the future, we need to conduct more integrated research across disciplines and methods and promote research interest in the underdeveloped area of sustainability research in human ecology.

• Genomics & Informatics
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• v.17 no.3
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• pp.26.1-26.12
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• 2019

Identification of fusion gene is of prominent importance in cancer research field because of their potential as carcinogenic drivers. RNA sequencing (RNA-Seq) data have been the most useful source for identification of fusion transcripts. Although a number of algorithms have been developed thus far, most programs produce too many false-positives, thus making experimental confirmation almost impossible. We still lack a reliable program that achieves high precision with reasonable recall rate. Here, we present FusionScan, a highly optimized tool for predicting fusion transcripts from RNA-Seq data. We specifically search for split reads composed of intact exons at the fusion boundaries. Using 269 known fusion cases as the reference, we have implemented various mapping and filtering strategies to remove false-positives without discarding genuine fusions. In the performance test using three cell line datasets with validated fusion cases (NCI-H660, K562, and MCF-7), FusionScan outperformed other existing programs by a considerable margin, achieving the precision and recall rates of 60% and 79%, respectively. Simulation test also demonstrated that FusionScan recovered most of true positives without producing an overwhelming number of false-positives regardless of sequencing depth and read length. The computation time was comparable to other leading tools. We also provide several curative means to help users investigate the details of fusion candidates easily. We believe that FusionScan would be a reliable, efficient and convenient program for detecting fusion transcripts that meet the requirements in the clinical and experimental community. FusionScan is freely available at http://fusionscan.ewha.ac.kr/.