• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2519-2522
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• 2014

Recently, the observation of the electrocatalytic behavior of individual nanoparticles (NPs) by electrochemical amplification method has been reported. For example, the Iridium oxide ($IrO_x$) NP collision on the Pt UME was observed via electrocatalytic water oxidation. However, the bare Pt UME had poor reproducibility for the observation of NP collision signal and required an inconvenient surface pre-treatment for the usage. In this manuscript, we has been investigated other metal electrode such as Cu UME for the reproducible data analysis and convenient use. The $IrO_x$ NP collision was successively observed on the bare Cu UME and the reproducibility in collision frequency was improved comparing with previous case using the $NaBH_4$ pre-treated Pt UME. Also, the adhesion coefficient between NP and the Cu UME was studied for better understanding of the single NP collision system.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.11
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• pp.1307-1317
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• 2003

The level of consumer knowledge has been gradually increased with the growth of living standard of consumer and the development of communication technology. The purpose of this study was to investigate the structure and measure of consumer knowledge and to find out relationship between objective knowledge and subjective knowledge. The subjects of this study were female adults from theirs twenties to theirs forties who lived in Seoul, Kyunggi or Incheon areas and Quota sampling method was used age and areas. The data were obtained from 603 questionnaires. Data were statistically analyzed using SPSS 10 and major statistical methods are mean, frequency, Pearson correlation coefficient, and Cronbach's $\alpha$ coefficient. The results are as follows: 1. Objective knowledge consisted of the product knowledge, brand knowledge, purchase knowledge and usage knowledge, and subjective knowledge consisted of experience and self-evaluation knowledge. 2. Consumer knowledge was related to the subjective knowledge and objective knowledge. But, there was relatively a low relationship between subjective knowledge and objective knowledge of apparel.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.264-269
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• 2001

Axial fans are widely used in household electrical appliances due to their easy usage and high flow rate for cooling capacity. At the same time, the noise generated by these fans causes one of serious problems. In order to calculate the noise of a fan, we develop the software IFD - Intranet Fans Design. With this software we can design, analysis the performance and predict the noise of fan. The prediction model, which allowed the calculation of acoustic pressure at the blade passing frequency and it's higher harmonic frequencies, has been developed by Lowson's equation. To calculate the unsteady resultant force of the blade, time-marching free-wake method is used. The objective of this study is to calculate the effects of number of blades, rotating velocity, and sweep angle on the noise of fan..

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.270-274
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• 2001

Fans are widely used in household electrical appliances due to their easy usage and high performance for cooling capacity. However, the noise generated by these fans causes one of serious problems. LG electronics makes the intranet software for design and analysis of fan. Axial, sirocco and centrifugal fan can be designed and analyzed by using the IFD(Intranet Based Fans Design) software. In order to calculate the aeroacoustic noise of a fan, the numerical method, which can calculate the acoustic pressure at the blade passing frequency and its higher harmonic frequencies, has been developed. To calculate the unsteady resultant force of the blade, vortex method is used. This paper shows the overview of the software and validates the accuracy of predicted noise of fan.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.5
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• pp.594-601
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• 2016

Mass estimation analysis of loose-parts in pressure vessel is necessary for the structural integrity assessment of pressure boundary in nuclear power plants. Mass of loose-parts can be generally estimated from the peak values and the center frequency of impact signals. Magnitude of impact signals is, however, inevitably attenuated according to the traveling distance of the signals and depending on the frequencies. Attenuation rate must be therefore carefully compensated for the precise estimation of loose-part mass. This paper proposes a new compensation method for the attenuation rate based on Bessel function instead of Hankel function in conventional method which has a limitation of usage in near the impact location. It was verified that the suggested compensating equation based on the Bessel function can be applied to the attenuation rate calculation without any limitation.

• Korean Journal of Child Studies
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• v.28 no.5
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• pp.19-36
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• 2007

This study explored proverb comprehension and use in elementary school children by familarity and concreteness of proverbs and children's age, sex, experience of living with grandparents. The 529 fourth and sixth grade participants completed a questionnaire probing knowledge of 16 proverbs; 4 each in four categories(familiar-concrete, familiar-abstract, unfamiliar-concrete, and unfamiliar-abstract). Results showed highest comprehension scores for familiar-concrete proverbs. Sixth graders obtained higher comprehension score than fourth graders in all four proverb categories. There was no difference between grades in frequency of proverb usage. An interaction effect between grade and sex showed that female sixth graders had the highest comprehension score. These results suggest a possibility of relationship between figurative language and cognitive development related to abstract thinking in late school-age children.

• 한국정보통신설비학회:학술대회논문집
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• 2006.08a
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• pp.35-38
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• 2006

Using the repeaters is indispensable to WiBro services. Repeater types are distinguished by usage, output power and required performance. In the paper, we have studied on the WiBro digital optic repeater design which has excellent performance characteristic than any other repeaters. WiBro has specific characteristic on modulation method TDD(Time Division Duplex)/OFDMA(Orthogonal Frequency Division Multiple Access) so that it demands specified H/W to design WiBro repeater. Switching technique has been introduced because of TDD characteristic in each amplifier on the repeater. Time Advance technique has been considered because of OFDM characteristic among RAS(Radio Access Station) and repeater. In this paper, we have studied on these techniques to increase repeater cell coverage and distance between RAS and repeater.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2013.11a
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• pp.206-208
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• 2013

국내 케이블TV는 이날로그방송 뿐만 아니라 디지털방송, 주문형 비디오, 초고속 인터넷, 양방향 서비스, 인터넷 전화 등의 다양한 서비스를 제공하고 있다. 하지만 종편, 보도, 홈쇼핑 등의 신규 채널 증가와 방송 통신 융합에 따른 다양한 양방향 서비스 도입, 시속적인 HD채널 확대 등으로 헌재 사용 가능한 주파수가 매우 부족한 상황으로 3DTV, UHDTV, 인터넷 기반방송 등의 차세대 방송 서비스 제공을 위한 주파수 확보 방안 마련 이 매우 시급하게 필요한 상황이다. 본 논문에서는 국내 케이블TV의 주파수 이용 현황 및 신규 주파수 수요 전망을 예측하고 다양한 효율적인 주파수 해결 방법을 모색하고 단계적으로 해결 방법을 적용하여 주파수를 확보하는 효율적인 주파수 이용방안에 대해서 기술하였다.

• Journal of the Korean Society for Library and Information Science
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• v.43 no.1
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• pp.113-133
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• 2009

This study suggests a scheme to activate an e-book service through the analysis on the cause of low usage of the services in academic libraries. The data analysis of e-book circulation records was performed for the purpose of preparing the scheme. Frequency analysis and descriptive statistics were used for basic data analysis. Also, t-test, ANOVA, non-parametric chi-square, and correlation analysis were used to examine whether there are any significant differences between treatment groups divided by gender and major.

• Fashion & Textile Research Journal
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• v.6 no.5
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• pp.585-594
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• 2004

This study aimed to classify the lifestyles of 1020 college students, and to analyze the effect of the lifestyles on the usages of credit card, price perception, purchasing satisfaction and the number of new clothing. The number of credit cards, total payment of credit cards and the attitude to credit card were different by the 7 clusters of college students, but the frequency of credit card use, the amount of cash service and arrear ages were not different. The perception to the apparel price, purchasing satisfaction, and the degree of clothing purchasing varied according to the lifestyle clusters. For example, 6th cluster being highest in the pursuit of appearance showed the highest amount of credit cards usage significantly and tendency of highest arrearage, and used credit cards mostly in clothing purchase.