• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.1
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• pp.20-27
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• 2003

In this paper, we implemented a content-based image retrieval system that user can choose a wanted query region of object and retrieve similar object from image database. Query image is induced to wavelet transformation after divided into hue components and gray components that hue features is extracted through color autocorrelogram and dispersion in hue components. Texture feature is extracted through autocorrelogram and GLCM in gray components also. Using features of two components, retrieval is processed to compare each similarity with database image. In here, weight value is applied to each similarity value. We make up for each defect by deriving features from two components beside one that elevations of recall and precision are verified in experiment results. Moreover, retrieval efficiency is improved by weight value. And various features of database images are indexed automatically in feature library that make possible to rapid image retrieval.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.619-624
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• 2007

Species of genus Acanthopanax(Araliaceae) are long-lived trees primarily distributed throughout East Asia. These species are regarded as medically and ecologically important in Korea. A variety of Cheongsong in Korea is one of these cultivated varieties, however this variety is much longer(>100 years) than those of other cultivated groups. The components of variety of Acanthopanax in Cheongsong were analyzed for the first time and were compared to those of all Acanthopanax taxa in Korea. Nineteen components were specific to variety in Cheongsong. The main components of this variety were $\beta$-caryophyllene, hexadecanoic acid and ethyl stearate. Although some components are differ from each other, variety Cheongsong was similar to A. senticosus at phonetic topology with content of the chemicals, In addition, six species of genus Acanthopanax were investigated to compare the major chemical components by GC-MS.

• ETRI Journal
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• v.43 no.5
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• pp.909-915
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• 2021

GaAs on Si grown via metalorganic chemical vapor deposition is demonstrated using various Si substrate thicknesses and three types of dislocation filter layers (DFLs). The bowing was used to measure wafer-scale characteristics. The surface morphology and electron channeling contrast imaging (ECCI) were used to analyze the material quality of GaAs films. Only 3-㎛ bowing was observed using the 725-㎛-thick Si substrate. The bowing shows similar levels among the samples with DFLs, indicating that the Si substrate thickness mostly determines the bowing. According to the surface morphology and ECCI results, the compressive strained indium gallium arsenide/GaAs DFLs show an atomically flat surface with a root mean square value of 1.288 nm and minimum threading dislocation density (TDD) value of 2.4×10⁷ cm^-2. For lattice-matched DFLs, the indium gallium phosphide/GaAs DFLs are more effective in reducing the TDD than aluminum gallium arsenide/GaAs DFLs. Finally, we found that the strained DFLs can block propagate TDD effectively. The strained DFLs on the 725-㎛-thick Si substrate can be used for the large-scale integration of GaAs on Si with less bowing and low TDD.

• Journal of Korean Elementary Science Education
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• v.41 no.1
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• pp.14-29
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• 2022

The purpose of this study is to investigate the components of scientific attitude by some learning topics in the 3rd~6th grade science textbooks that the pre-service elementary school teachers judge to be teachable in class and the educational effects of this analysis activity for the pre-service teachers. The several results of this study are as follows: The pre-service teachers responded that, for all learning topics, they could teach diverse components of scientific attitude and the number of components expressed in their responses is more than the components specified in the teacher's guides. Among the components of scientific attitude, 'curiosity', 'open-mindedness', 'respect for evidence', and 'objectivity' showed relatively high possibility of teaching, while 'honesty', 'collaboration', 'positive acceptance of failure', 'critical mind' and 'suspension of judgment' showed relatively low possibility of teaching. The responses that pre-service teachers judged to be teachable also showed similar patterns in the number of components of scientific attitude and the rate of the components between the learning topics of the 3~4th grades and the learning topics of the 5~6th grades. In addition, this pre-service teachers' analysis activity on the components of scientific attitude by learning topics in science textbooks suggested educational effects such as 'the deep understanding of the components of scientific attitude', 'the understanding and applying the components of scientific attitude in the context of science class', and so on.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.2
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• pp.83-91
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• 2022

Seismic design and analysis of nuclear power plant components are performed based on an decoupled model. However, this decoupled analysis has a limitation in that it generates inaccurate results compared to the coupled analysis because it cannot simulate actual phenomena such as the interaction between structures and components. Thus, this study performed seismic coupled and decoupled analysis on an existing nuclear containment structure and related components, considering the mass and natural frequency ratios. And based on these results, comparative analyses of responses of components were conducted. Consequently, the seismic coupled analysis result generally gave a smaller value than the decoupled analysis result. These results were similar to the analysis results for the simple coupled model, which was an existing study, but the difference in component responses was much more pronounced. Also, this was influenced by the installation location of the component rather than the influence of the input frequency of the input seismic motions. Finally, the difference between the decoupled and coupled seismic analysis occurred in the region where the mass ratio of the components was large, and the natural frequencies were almost similar due to the considerable dynamic interaction between the structure and the component in this realm.

• Journal of Biomedical Engineering Research
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• v.41 no.1
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• pp.42-47
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• 2020

A personal authentication system based on biosignals has received increasing attention due to its relatively high security as compared to traditional authentication systems based on a key and password. Electrocardiography (ECG) measured from the chest or wrist is one of the widely used biosignals to develop a personal authentication system. In this study, we investigated the feasibility of using similar ECG measured behind the ears to develop a personal authentication system. To this end, similar ECGs were measured from thirty subjects using a pair of three electrodes attached behind each of the ears during resting state during which the standard Lead-I ECG was also simultaneously measured from both wrists as baseline ECG. The three ECG components, Q, R, and S, were extracted for each subject as classification features, and authentication accuracy was estimated using support vector machine (SVM) based on a 5×5-fold cross-validation. The mean authentication accuracies of Lead I-ECG and similar ECG were 90.41 ± 8.26% and 81.15 ± 7.54%, respectively. Considering a chance level of 3.33% (=1/30), the mean authentication performance of similar ECG could demonstrate the feasibility of using similar ECG measured behind the ears on the development of a personal authentication system.

• Korean Journal of Applied Biomechanics
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• v.25 no.2
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• pp.157-165
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• 2015

Object : The goals of this research were to make Performance Enhanced Model(PE) taken the largest performance index (PI) through artificial variation of principle components calculated by principle component analysis for trial data, and to verify the effect through comparing kinematic factors between trial data (Raw) and PE. Method : Ten subjects (5 men, 5 women) were recruited and 80% of their maximal record was considered. The PI is a regression equation. In order to develop PE, we extracted Principle components from trial position data (by Principle Components Analysis (PCA)). Before PCA, we made 17 position data to 3 row matrix according to components. We calculated 3 eigen value (principle components) through PCA. And except Y (medial-lateral direction) component (because motion of Y component is small), principle components of X (anterior-posterior direction) and Z (vertical direction) components were changed as following. Changed principle components = principle components + principle components ${\times}$ k. After changing the each principle component, we reconstructed position data using the changed principle components and calculated performance index (PI). A Paired t-test was used to compare Raw data and Performance Enhanced Model data. The level of statistical significance was set at $p{\leq}0.05$. Result : The PI was significantly increased about 12.9kg at PE ($101.92{\pm}6.25$) when compared to the Raw data ($91.29{\pm}7.10$). It means that performance can be increased by optimizing 3D positions. The difference of kinematic factors as follows : the movement distance of the bar from start to lock out was significantly larger (about 1cm) for PE, the width of anterior-posterior bar position in full phase was significantly wider (about 1.3cm) for PE and the horizontal displacement toward the weightlifter after beginning of descent from maximal height was significantly greater (about 0.4cm) for PE. Additionally, the minimum knee angle in the 2-pull phase was significantly smaller (approximately 2.7cm) for the PE compared to that of the Raw. PE was decided at proximal position from the Raw (origin point (0,0)) of PC variation). Conclusion : PI was decided at proximal position from the Raw (origin point (0,0)) of PC variation). This means that Performance Enhanced Model was decided by similar motion to the Raw without a great change. Therefore, weightlifters could be accept Performance Enhanced Model easily, comfortably and without large stress. The Performance Enhance Model can provide training direction for athletes to improve their weightlifting records.

• Journal of Photoscience
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• v.9 no.2
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• pp.296-298
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• 2002

Irreversible photobleaching of bacteriorhodopsin (bR), namely denaturation induced by illumination of visible light, was investigated by absorption kinetic measurements. The denaturation kinetics revealed that light illumination significantly enhanced the structural decay of bR. The kinetic analyses showed that the molecular structure of bR denatures according to a single-exponential decay, whereas irreversible photobleaching has two decay components. The decay constant of the slow component of photobleaching is almost same as that in the dark. An Arrhenius plot of the denaturation kinetic constants for the fast and slow components showed similar activation energies of approximately 19 kcal/mol.

• Journal of the Korean Society of Tobacco Science
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• v.4 no.2
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• pp.31-36
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• 1982

The field evaluation were conducted on dihaploid progenies derived from anther culture of F1 plant of Drama x Sohyang (N. tabacum L.) The mean values of agronomic and chemical traits of dihaploids such as Nicotine, length/width, plant height, Leaf length, leaves per plant and Yield were greater than those of tar parents. The correlation coefficient of dihaploids were similar to those of conventional lines and varieties. In path analysis, in relating yield components to yield, leaves per plant and leaf width had a direct effect on Yield, but the other components such as plant height, leaf length and days to flowering influenced Yield indirect way.

• International Journal of Fluid Machinery and Systems
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• v.3 no.2
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• pp.137-149
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• 2010

The purpose of the present research is to suppress cavitation instabilities by using a circumferential groove. The circumferential groove was designed based on CFD so that the tip leakage vortex is trapped by the groove and does not interact with the next blade. Experimental results show that the groove can suppress rotating cavitation, asymmetric cavitation and cavitation surge. However, weak instabilities with higher frequency could not be suppressed by the groove. From the analysis of pressure pattern similar to that for rotor-stator interaction, it was found that the higher frequency components are caused by the interaction of backflow vortices with the inducer blades.