• The Journal of the Acoustical Society of Korea
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• v.26 no.5
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• pp.220-226
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• 2007

The two major objectives of acoustical measurements in a cavitation tunnel are measuring the noise levels generated by rotating propellers behind a hull and localizing possible noise sources in order to reduce noise levels. Propeller noise measurement experiments were performed in MOERI cavitation tunnel at December, 2006. In order to put the propeller into cavitating conditions, a wake-generating dummy body was devised. In addition, ten hydrophones are put inside a wing-shaped casing in order to minimize the unexpected flow induced self noise around hydrophone itself. After measuring both of the noises of the rotating propeller behind the dummy body and signals generated by a virtual source, respectively the data were matched field processed using the frequency incoherent Bartlett processor to localize noises on the propeller plane. In this paper, we presented the measured noise analysis and the localization results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.772-779
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• 2019

This study identified the relationship between leisure attitudes, leisure promotion, leisure drugs, leisure satisfaction, and the intention to rejoin maritime sports by the participants of this study. The researchers selected 542 adult men and women who live in Seoul and the Incheon, Gyeonggi and Chungcheong provinces, and who were currently engaged in marine sports activities. Data processing was performed using SPSS 21.0 and AMOS 18.0 for the frequency analysis, reliability analysis, confirmatory factor analysis, correlation analysis and structural equation model analysis. The results of this study were as follows. First, the leisure attitudes of marine sports participants did not affect the promotion of leisure (p>.05). Second, the attitude towards leisure of the marine sports participants had a negative effect on using leisure pharmaceuticals (p<.05). Third, the leisure attitudes of marine sports participants affected their leisure satisfaction (p<.05). Fourth, the promotion of leisure activities of the marine sports participants did not affect their leisure satisfaction (p>.05). Fifth, the leisure restrictions of marine sports participants did not affect their leisure satisfaction (p>.05). Sixth, the leisure activities of marine sports participants affected the intention of rejoining (p<.05).

• Cross-Cultural Studies
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• v.48
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• pp.391-417
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• 2017

Southeast Asian languages are famous for having a large number of vowel sounds with an average of more than 20 vowel sounds in this certain language family. In addition, there are approximately 1,500 languages in this area, which accounts for approximately 20% of total languages in the world. For this reason, vowel systems of Southeast Asian languages should be explored to determine the nature of vowel structures of human natural languages. In this study, we analyze vowel systems of three languages, Tagalog, Malay and Thai, that have only primary or normal vowels and thus are relatively simple structures based on descriptive and analytic universals. We would also like to confirm if the six criteria of the tentative evaluation model taken from several previous literature is appropriate in applying analysis of vowel system universals under the method of the Greenbergian Universals or statistic universals. What we have found from this research are (i) the three languages have high level of universals with some exceptional cases such as three-vowel system of Tagalog, and (ii) some of the six criteria, together with some cases of analytic universals, are not quite suitable for understanding language-specific universals that are different from other languages.

• Journal of the Korean Applied Science and Technology
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• v.36 no.1
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• pp.312-323
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• 2019

This purpose of study was to influence of elementary school student's Judo gym training program on social development and life satisfaction. This study aims at providing fundamental data and information on Judo participants by studying what effects of training program characteristic on social development and life satisfaction. The survey was done through 300 copies and excluding 15 copies ran an analysis on the remaining 285(90%) copies. After question investigating the data which is collected used IBM SPSS statistics 21 and IBM AMOS 21 program, frequency analysis, Exploratory factor analysis and confirmatory factor analysis, convergent validity, discriminant validity, Cronbach's ${\alpha}$, correlation analysis, path analysis through Structural Equation Model(SEM), mediation effect analysis by Sobel test. The result of this study were as follows. First, elementary school student's Judo gym training program showed (+) effects on social development. Second, elementary school student's Judo gym training program had no effects on life satisfaction. Third, social development showed (+) effects on life satisfaction. Forth, social development showed complete mediation effect on elementary school student's Judo gym training program and life satisfaction.

• Journal of Korea Entertainment Industry Association
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• v.14 no.8
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• pp.381-390
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• 2020

This purpose of study was to influence of fitness club leader's emotional labor on job involvement and occupation performance. This study aims at providing fundamental data and information on fitness club leader's emotional labor. The survey was done through 250 copies and excluding 23 copies ran an analysis on the remaining 227(90.8%) copies. After question investigating the data which is collected used IBM SPSS statistics 21 and IBM AMOS 21 program, frequency analysis, Exploratory factor analysis and confirmatory factor analysis, convergent validity, discriminant validity, Cronbach's α, correlation analysis, path analysis through Structural Equation Model(SEM). The result of this study were as follows. First, fitness club leader's emotional labor showed (-) effects on job involvement. Second, fitness club leader's emotional labor showed (-) effect on occupation performance. Third, job involvement showed (+) effects on occupation performance. Fitness instructors have severe emotional labor. Therefore fitness instructors manage their emotional labor. This can increase job commitment and job performance. For teeth manager need to increase support options from fitness instructors.

• Asia Marketing Journal
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• v.7 no.1
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• pp.21-42
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• 2005

Customer Relationship Management (CRM) is a corporate marketing strategy maintaining and managing customers. And with CRM companies maximize the customer's value through a series of processes of new customer retention, VIP customer retention, customer value increase, potential customer activation, and customers for lifetime by collecting the customer information and taking advantage of it effectively. In particular, as the competitive environment is changing rapidly and getting more intense, maintaining the customer retention through customer churn management becomes more important in order to increase the customer value for maximizing the company's profit and to build up the relationship with customers. For example, the financial industry has managed the customer churn with the concept of customer segmentation. Recently the customer retention and churn management is becoming increasingly important in all business fields as well as financial industry since the companies expect the effect of preventing the customer churn by identifying characteristics of customers. However, despite the increasing interest and importance of the management of the customer churn, not many of studies are systematically executed by analyzing the data of customer churn. In this study we analyze the actual data of CRM activities for the customer retention, specifically the data of TV home-shopping. By doing so, we hope to identify the differences of demographic attributes and transaction specific characteristics in consumer behaviors between the churning customer and the retained customers. In addition, we try to find out the variables which can impact the churning of the customers and to predict the churn rate of individual customer through our proposed model of customer churn. In the end, based on our findings we suggest the possible marketing strategies for TV home-shopping companies.

• Journal of Korean Society of Steel Construction
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• v.17 no.1 s.74
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• pp.1-11
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• 2005

A bi-level damage detection algorithm that utilizes the dynamic responses of the structure as input and neural network (NN) as pattern classifier is presented. Signal anomaly index (SAI) is proposed to express the amount of changes in the shape of frequency response functions (FRF) or strain frequency response function (SFRF). SAI is calculated using the acceleration and dynamic strain responses acquired from intact and damaged states of the structure. In a bi-level damage identification algorithm, the presence of damage is first identified from the magnitude of the SAI value, then the location of the damage is identified using the pattern recognition capability of NN. The proposed algorithm is applied to an experimental model bridge to demonstrate the feasibility of the algorithm. Numerically simulated signals are used for training the NN, and experimentally-acquired signals are used to test the NN. The results of this example application suggest that the SAI-based pattern recognition approach may be applied to the structural health monitoring system for a real bridge.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.4
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• pp.617-625
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• 2016

The objective of this study was to evaluate the groundwater drawdown and streamflow depletion due to each groundwater pumping from 110 wells located near stream using the Hunt's analytical solution (1999). The calculated results revealed that the streamflow depletion rate divided by the pumping rate for each well location mostly exceeded about 80% of pumping rate on average for 5 years. The results also showed that the stream boundary condition has made the influence distance shorter and the drawdown distribution skewed except for the streambed hydraulic conductivity and the stream bed factor (SBF) lower than $1.0{\times}10^{-9}m/s$ and 1.0, respectively. It was found that the groundwater pumping has significant impacts on the stream depletion showing above 80 % of stream depletion rate when the streambed hydraulic conductivity is higher than $1.0{\times}10^{-7}m/s$ and the stream depletion factor(SDF) is lower than 100. However, for other conditions, the SDF is not sufficient to be used as a criterion for determining whether the pumping has great impacts on stream depletion or not. Furthermore, the variation of the streambed hydraulic conductance has little change in stream depletion rate for the condition that the stream width is greater than 400 m.

• Journal of dental hygiene science
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• v.14 no.2
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• pp.198-206
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• 2014

The purpose of this study was to develop and validate tool for measuring the communication skills of dental hygienist. The survey was modified and revised to fit into Korean culture. Also the reliability and validity was tested in order to ensure the survey was properly evaluating communication skills of dental hygienists. A survey was conducted with outpatients in dental clinics located in Seoul, Gyeonggi, and Daejeon area. The 483 answers out of the total collected answers were used for the final analysis of the study, using PASW Statistics 18.0 and IBM SPSS AMOS 7.0 to measure the validity and reliability. The factor analysis showed that the communication skill of the dental hygienists was composed of three elements, namely 'being caring and respectful' communications, 'sharing information' communications and 'tending to comfort' communications to reduce pain and anxiety. The validity of the model examined by a confirmatory factor analysis satisfied most of the relevant requirements. All of the factors had the conceptual reliability and variant extracted index above the minimum requirements, ensuring reliability and concentrated validity. Also, the value of the square of the correlations between all latent factors which was larger than the square of the correlation between all of the factors, thus proving the discriment validity. Cronbach's ${\alpha}$ was 0.8, which shows high reliability level. In conclusion, it was proven that dental hygienist's communication skill measurement tool has high validity and reliability. Further, this study can be used to improve dental hygienists' communication skills. Therefore, this will improve oral health of clients and manage them.

• Journal of Navigation and Port Research
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• v.44 no.4
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• pp.338-346
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• 2020

In this study, we first measured the Malmquist productivity index by DEA among the Korean ocean carriers. Second, it was intended to present measures to improve productivity by identifying the influence and discriminating power between productivity and the major financial ratios (profitability, financial stability, liquidity, efficiency and value-added productivity). Compared to 2017, there are 11 more shipping carriers with decline in productivity (MPI) than those with an increase in 2018. The increase in productivity is attributed to an increase in the Technology Change Index (TCI) affected by the external environment. There is strong significant correlation between the productivity (MPI) and the management efficiency (CRS). Additionally, the TECI (TECHI) index of the technological efficiency changes from internal factors of the shipping carrier is significantly higher than that of the efficient shipping carrier. This is because of the differences in scale efficiency. The ratio of charter cost/sales is also lower than that of the carriers with high productivity (0.17) and with low productivity (0.21). With 7% of the shipping carrier with MPI>1, only 1% of MPI <1 is found to have a significant impact on its productivity.