• The Journal of the Acoustical Society of Korea
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• v.32 no.2
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• pp.138-146
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• 2013

Passive sonars employ DEMON (Detection of Envelope Modulation on Noise) processing to extract propeller information from the radiated noise of underwater targets. Conventional DEMON processing improves SNR(Signal to Noise Ratio) characteristic by Welch method. The conventional Welch method overlaps several different time domain DEMON outputs to reduce the variance. However, the conventional methods have high computational complexity to get high SNR with correlated acoustic signals. In this paper, we propose new DEMON processing method that divides acoustic signal into several frequency bands before DEMON processing and averages each DEMON outputs. Therefore, the proposed method gathers independent acoustic signal faster than conventional method with low computational complexity. We prove the performance of the proposed method with mathematical analysis and computer simulations.

• International Journal of Quality Innovation
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• v.6 no.1
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• pp.24-34
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• 2005

This research topic evaluates the effectiveness and importance of environmental protection in the 21st century in light of the increasing demand on the earth's natural resources and the pressures on economic and industrial development to provide dynamic power. As the world and our fellow citizens become more conscious of environmental protection, companies are under greater pressure whilst pursuing economic growth. Therefore, domestic manufacturers have been devoting efforts to promote environmental management. This research conducts survey using questionnaires on the operational performance of the manufacturers who have ISO 14000 series accreditation and certification. The survey considers five dimensions/functions within a manufacturer, financial management, human resources management, production management, and marketing management. A total of 35 indices are used for analysis of the effects that the location, history, industry, number of employees, amount of capital, and revenue may have on the performance. This research targets the manufacturers approved of ISO 14000 series certification by Environment Administration Association. The statistical methods deployed are descriptive statistics, T-test, and single factor analysis of variance used for analysis. The conclusions reveal that a certain level of performance has been achieved in every dimension. After T-test, all the indices have reached a significant level. The indications are that ISO 14001 benefits all manufacturers the level of benefits however varies from company to company.

• Journal of Korean Institute of Industrial Engineers
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• v.37 no.2
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• pp.105-117
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• 2011

This study describes behavioral characteristics of Korean population over twenty years old in a variety of activities of daily living by analyzing the raw data of the time use survey provided by Statistics Korea (KOSTAT). Seven activities and forty four sub-activities of daily living were selected for analysis : personal care, employment, household care, family care, voluntary work and community participation, social life, recreation and leisure, and travel. In order to quantitatively understand how Korean adults spend their time for a day and how their lifestyle changes over time, we collected the time recorded by 3,673 respondents in three surveys over the past ten years (in 1999, 2004, and 2009). Then, we performed analysis of variance to compare the behavioral characteristics by user age and gender based on the mean time of each activity. The differences in behavior among user groups and over time could be used to design ergonomic products and services based on user experience, especially for universal design of housing and transportation facilities.

• Journal of Korean Academy of Nursing
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• v.18 no.2
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• pp.153-161
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• 1988

The purpose of this study was to analyze the level of the services provision of community health practitioners (CHP) and to find out the influence factors on the services provision of CHP. In this study the dependent variables were the level of community health services(CHS), maternal and child health services(MCH), family planning services(FPS), primary care services(PCS) and the ratios of preventive health services(PHS). And independent variables were predisposing, community demographic and task factors. For this analysis, atepwise regression was used. Data collected for the study on reorganization of health centers organization in 1985 was partly used. The findings of this study can be summarized as follows : First, total variance of independent variables for CHS, MCH, FPS, PCS and PHS are shown 62.5 percent, 58.3 percent, 41.8 percent, 17 percent and 61.9 percent respectively. Second, the most important variables which explain CHS, MCH, FPS, PCS and PHS was ratios of household contacted ($R^2$＝0.289), marital status ($R^2$＝0.177), marital status($R^2$＝0.167), ratios of household contacted($R^2$＝0.119) and management of preventive health services($R^2$＝=0.203) respectively. The independent varivbles used in this analysis presented that the explnining for the provision of preventive health service are more influenced than primary care services. In summary this analysis suggests that the level of preventive health services provision of CHP is low and the provision of primary care services compared with preventive health services are occurred independentely. In the future, the strategies for active preventive services by CHP must to be strengthened.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.6
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• pp.1008-1017
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• 2010

The current study aims to determine the effects of descriptive menu labels on customers' purchase intentions in a restaurant setting. The research identified the importance of information provided by the menu labels as well as how the different types of descriptive menu labels affect patrons' purchase intentions in an American-style restaurant. The subjects evaluated in this study were foreign clients who frequented the Western cuisine restaurant in the United States Forces Korea. A total of 351 questionnaires were analyzed by factor analysis, analysis of variance (ANOVA), and regression analysis by means of SPSS 15.0. As a result, it was found that comprehension of menu and price were the most necessary pieces of information for customers encountering menu labels, and sensory type of descriptive menu labels was the most preferred. In addition, differences in the purchase intentions of customers in response to different types of descriptive menu labels suggests that there were more statistically significant differences in the perception of purchase intention among descriptive labels as compared to usual menu labels.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.7
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• pp.91-101
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• 2021

The paper examines the impact of the COVID-19 pandemic on the stock market prices. The vector autoregression model (VAR) has been used in this analysis to survey 341 stocks on the Ho Chi Minh City Stock Exchange (HOSE) for the period from January 23, 2020 to December 31, 2020. The empirical results obtained from the analysis of 11 economic sectors suggest that there is a statistically significant impact relationship between COVID-19 and the healthcare and utility industries. Additional findings show a statistically significant negative impact of COVID-19 on the utility share price at lag 1. Analysis of impulse response function (IRF) and forecast error variance decomposition (FEVD) show an inverse reaction of utility stock prices to the impact of COVID-19 and a gradual disappearing shock after two steps. Major findings show that there is a clear negative effect of the COVID-19 pandemic on share prices, and the daily increase in the number of confirmed cases, indicate that, in future disease outbreaks, early containment measures and positive responses are necessary conditions for governments and nations to protect stock markets from excessive depreciation. Utility stocks are among the most severely impacted shares on financial exchanges during a pandemic due to the high risk of immediate or irreversible closure of manufacturing lines and poor demand for basic amenities.

• Restorative Dentistry and Endodontics
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• v.47 no.3
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• pp.28.1-28.12
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• 2022

Objectives: Metalloproteinase-inhibiting agents, such as chitosan, can prevent collagen degradation in demineralized dental substrates, thereby improving the adhesive interface. This study evaluated the bond strength (BS) and chemical and morphological characterization of the adhesive interface after applying chitosan solution to demineralized dentin. Materials and Methods: The 80 third molars were selected. Forty teeth underwent caries induction using the pH cycling method. The teeth were divided according to the treatment: distilled water (control) and 2.5% chitosan solution. The surfaces were restored using adhesive and composite resins. Half of the specimens in each group were aged, and the other half underwent immediate analyses. The teeth were sectioned and underwent the microtensile bond strength test (µTBS), and chemical and morphological analyses using energy-dispersive spectroscopy and scanning electron microscopy, respectively. Data analysis was performed using 3-way analysis of variance. Results: For µTBS, sound dentin was superior to demineralized dentin (p < 0.001), chitosan-treated specimens had higher bond strength than the untreated ones (p < 0.001), and those that underwent immediate analysis had higher values than the aged specimens (p = 0.019). No significant differences were observed in the chemical or morphological compositions. Conclusions: Chitosan treatment improved bond strength both immediately and after aging, even in demineralized dentin.

• Journal of Korean Academy of Nursing
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• v.19 no.3
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• pp.273-284
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• 1989

The aim of this investigation was to delineate concepts contributing to the Exercise of Self-Care Agency (E.S.C.A.) Scale developed by Kearney & Fleischer (1979) and to test its construct validity and its predictors. The results are summarized as follows ; 1. By means of principal factor analysis and maximal likelihood factor analysis upon data generated from 280 undergraduate students, the factors of Concern about Health Knowledge, self-Concept, Information - Seeking Behavior, Decision -making and Responsibility, Self-esteem, and Passivity emerged. The total percent of variance explained by the 6 factors was 75.1% 2. To assess factor independence and instrument homogeneity, correlations among the 6 factors were computed. The correlations ranged from .24 to .46 indicating that the factors and the items were not too similar or redundant. 3. Test-retest reliability of the total scale is r＝.70. Cronbach's $\alpha$ coefficient for internal consistency of the total scale is .86 and that of the factors ranged from .750 to .661 (only factor 6 .497). 4. In additional analysis of the Exercise of Self-Care Agency Scale in relationship to Multiple Health Locus of Control, Family Environmental Scale, and Cornell Medical Index using stepwise multiple regression, the Internal Health Locus of Control Score predicted 21.8%(F＝53.34, p＝.0001), Family Environmental Score 8.3%(F＝22.59, P＝.0001), Modified Cornell Medical Index Score 5.4%(F＝15.74, P＝.0001) of the score of the E.S.C.A.

• Journal of Oriental Neuropsychiatry
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• v.18 no.3
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• pp.15-21
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• 2007

This study was done to review problems in terms of statistical description and statistical application and analysis. Methods; The authors reviewed 42 statistical clinical study papers excluding 12 Overview papers, 75 Descriptive papers, 48 Animal studies out of 177 papers in the Journal of Oriental Neuropsychiatry in the 5 years from 2002 to 2006. Results : 1) 3 papers(7.1%) had no description of statistical method, only P-values, 25 papaers(59.5%) had tables without description of statistical method, 1 paper (2.3%) had no description of statistical method in study method. 2) 10 papers(23.8%) contained problems in terms of statistical application and analysis. 6papers (6/23, 26.0%) for Student t-test, 2 papers(2/7 28.6%)for $X^2$- test, 1 paper(1/15 6.7%) for the analysis of variance, 1 paper(1/6 16.7%) for Pearson correlation contained statistical problems. Conclusion : It was suggested that consultation of investigators with statisticians and more extensive statistical refereeing, the form of the guidelines for description and application of statistics are needed.

• International Journal of Contents
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• v.12 no.4
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• pp.76-82
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• 2016

This study aims to evaluate the effectiveness of the dual-punishment system by analysis of the financial performance of pharmaceutical companies before and after introduction of the dual-punishment system. This study analyzed the business performance of 136 pharmaceutical companies from 2009 to 2011. The results from paired t-tests found that sales, operating cost, and EBITDA showed significant differences in performance, and, according to the variance analysis, the five groups obtained through a hierarchical cluster analysis differed from each other in sales, operating cost, EBITDA, and research and development cost. Differences in financial performance among the groups seem to be related to the strategy for response to the regulation. The introduction of the dual-punishment system is generally acknowledged to have had positive effects on the pharmaceutical industry. However, some companies appear to be continuing kickback practices.