• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.4
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• pp.1-6
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• 2003

Steady flow bench test is a practical, powerful and widely used in most engine manufacturers to give a design concept of a new engine. In order to use steady data as a performance index, it is necessary to build some database, which can correlate the port characteristics with engine data. However, it is very difficult to investigate all port shapes with experimental tools. The steady flow scheme is relatively simple and its results are bulk ones such as flow rate and momentum of flow. Therefore a CFD code can be easily applied to the port evaluation. In this study, the steady flow test was simulated through three-dimensional analysis on intake port design for comparing with experimental data and confirming the feasibility of applying analytic method . for this purpose, the effect of valve curvature on flow rate was estimated by a CFD code. Numerical results were compared with those of real steady flow tests. As a result, the results of 3-D analysis were almost consistent with experimental data.

• Korean Journal of Adult Nursing
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• v.19 no.5
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• pp.37-46
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• 2007

Purpose: The purpose of this descriptive study was to identify predictors on health promoting behaviors of university students. Methods: The participants were 310 students by convenience sampling in G city. The data were collected through a questionnaire given to the students between September 10 to November 6, 2006. Descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients, and stepwise multiple regression were used to analyze the data. Results: The mean score for the level of health promoting behaviors and optimism was 2.60(${\pm} .31$) and 2.70(${\pm} .55$) respectively. The most frequently used coping skill was the pursuit of social support. There were positive correlations between health promoting behaviors and optimism, between health promoting behaviors and active coping skill, and between health promoting behaviors and passive coping skill. In stepwise multiple regression analysis, the most powerful predictor of health promoting behaviors was active coping skill. Conclusion: The results suggest that coping skills with optimism can be considered when developing a health promotion program for university students.

• The Journal of the Acoustical Society of Korea
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• v.26 no.1
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• pp.16-24
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• 2007

Voice activity detectors (VADs) are important in wireless communication and speech signal processing. In the conventional VAD methods. an expression for the likelihood ratio test (LRT) based on statistical models is derived. Then, speech or noise is decided by comparing the value of the expression with a threshold. We propose a new method with the modified decision rule based on the Gaussian distribution and the uniformly most power (UMP) test. This method requires the distribution of the absolute value of the incoming speech signal. Then we can obtain the final decision through the relation between the Rayleigh distributions. This VAD method can detect speech without a priori signal-to-noise ratio (SNR) which is required in the conventional VAD algorithms. Additionally, in the various VAD performance tests, the proposed VAD method is shown to be more effective than the traditional scheme.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4764-4769
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• 2011

This study intends to investigate the organizational commitment and Its related factors among medium hospital of nurses. The collected data were analyzed descriptive statistics, t-test, ANOVA, Scheffe's test, Pearson correlation coefficient and stepwise multiple regression using SPSS 19.0 Program. The score of level of organizational commitment was statistically significant difference according to working period, marital state, monthly income, personality, night-duty. The score of organizational commitment level correlated positively with job satisfaction and burnout. Stepwise multiple regression analysis for organizational commitment level revealed that the most powerful predictor was burnout, job satisfaction and night-duty explained 49.5% of the variance. Therefore, It suggested that goal of increasing nurses' organizational commitment in hospital should be helped them raise job satisfaction and decrease nurses' burnout and night duty.

• Journal of Korean Public Health Nursing
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• v.14 no.1
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• pp.161-171
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• 2000

The purpose of this study was to investigate the factors influencing health promoting behavior and quality of life in the nursing students, to provide the basic data for health promoting intervention in order to improve quality of life. The subjects of this study were 199 nursing students, living in M city, during the period from May 18 to 25, 1999. The instruments for this study were the health promoting behavior scale developed by Walker et al.(1987), the quality of life scale by Ro(1988), the self efficacy scale by Sherer(1982), the health locus of control scale by Wallston et al. (1978) and the self esteem scale by Rogenberg(1965). The data were analyzed using descriptive statistics, Pearson correlation coefficients, stepwise multiple regression, t-test, ANOVA. The results of this study are as follows; 1. The health promoting behavior showed significant positive correlation with self efficacy, self esteem, internal health locus of control and quality of life. 2. The quality of life showed significant positive correlation with self efficacy, self esteem, internal health locus of control. 3. Stepwise multiple regression analysis revealed that the most powerful predictor of health promoting behavior was self efficacy. A combination of self efficacy, self esteem, health locus of control and quality of life accounted for $41\%$ of the variance in health promoting behavior. 4. Stepwise multiple regression analysis revealed that the most powerful predictor of quality of life was self esteem. A combination of self esteem, self efficacy and health promoting behavior accounted for $40\%$ of the variance in quality of life. Based on the above findings, it is suggested to develop nursing intervention to improve Self Efficacy, Self Esteem of nursing students enhance health promoting lifestyle.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.921-927
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• 2001

Steady flow bench test is a practical, powerful and widely used test in most engine manufacturers to give a design concept of a new engine. In order to use steady data as a performance index, it is necessary to build some database, which can correlate the port characteristics with engine data. However, it is very hard to investigate all port and valve shapes with experimental tools. The steady flow scheme is relatively simple and its results are bulk ones such as flow rate and momentum of flow. Therefore a CFD code can be easily applied to the port evaluation. In this study, the steady flow test was simulated through two and three-dimensional analysis on intake port design for comparing with experimental data and confirming the feasibility of applying analytic method. For this purpose, the effect of valve curvature on flow rate was estimated by a CFD code. There results were compared with those of real steady flow tests. As a result, the 2-D analysis described the phenomena qualitatively well, and also the results of 3-D analysis were almost consistent with experimental data.

• Tunnel and Underground Space
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• v.19 no.5
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• pp.440-449
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• 2009

LCM test is one of the most powerful and reliable methods of experiment for the cutter head design and the performance prediction of TBM. In many cases, however, the predicted design model can be directly applied to the field design, because this test may have an uppermost limit in preparation and/or transportation of the large size rock samples and the test for the jointed rock mass is not easy. When the proper and reasonable numerical modeling is considered to overcome this limit, the most adequate cutter head design for TBM could be presented without any complicate preconsideration in the field. In this study, the crack propagation patterns dependent on the contact point of disc cutter and the angle of rock joint are analyzed for the rock specimen with a single joint using the UDEC. The authors could derive the appropriate contact points of disc cutters and their space with respect to the joint angle in rock mass thru the numerical analysis.

• Research in Community and Public Health Nursing
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• v.16 no.4
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• pp.458-466
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• 2005

Purpose: The purpose of this study was to determine the relation between test anxiety and mental health in adolescents. Method: The subjects were 450 students of two academic high schools in J City, who were selected through convenient sampling. Data were collected through a survey using a structured questionnaire from September 1st to 15th 2005. Collected data were analyzed using SPSS 10.0 for Windows through descriptive analysis, Pearson's Correlation Coefficient, t-test, ANOVA, Scheffe's test and stepwise multiple regression. Result: The mean score of test anxiety was 2.40 (range:1.13-3.81) and that of mental health was 2.77 (range:0.64-5.03). A significant negative correlation was observed between test anxiety and mental health (r=-0.28, p=.000). Test anxiety was significantly different according to adolescents' general characters such as gender (t=-1.98, p=.048), grade (F=3.54, p=.030), school life satisfaction (F=10.73, p=.000) and relationship with the teacher (F=11.60, p=.000). Mental health was significantly different according to adolescents' general characters such as religion (t=2.14, p=.032) and school life satisfaction (F=4.13, p=.017). The most powerful predictor of mental health was test anxiety and it, combined with religion, accounted for 9.0% of variance in mental health in adolescents. Conclusion: Test anxiety and mental health was found to be in a significant negative correlation with each other in adolescents. Therefore, nursing intervention programs for adolescents needs to reduce their test anxiety to improve their mental health.

• Proceedings of the KIPE Conference
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• 2013.11a
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• pp.37-38
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• 2013

This paper presents an intuitive and powerful way to study and design motor drive control. The control of induction motors, as most widely used machines, is discussed. Thanks to ultra low latency and high fidelity Hardware-in-the-Loop systems, different aspects of up-to-date drive regulation are examined. A power stage, comprised of a grid voltage source, a rectifier, a VSC inverter and an induction motor, is emulated on the HIL platform in real time. A digital signal controller is plugged into the interface board and connected to the HIL emulation platform, without any hardware modifications. For motor control and power electronics applications, a dedicated Texas Instruments TMS320F2808 DSP is chosen. The same controller can drive an emulation platform and a real device with no modifications. Current and speed control loop test results are presented and discussed.

• Journal of Korean Academy of Nursing
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• v.33 no.6
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• pp.762-771
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• 2003

Purpose: This study was undertaken in order to determine factors affecting health promoting lifestyle of elderly women. Method: The subjects were 299 elderly community residing women over the age 65 living in 2 large cities. The instruments used for this study were a survey of general characteristics, health promoting lifestyle(47items), perceived health status(6 items), self-efficacy(l7 items), and social support(18 items). The data was analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients, and Stepwise Multiple Regression. Result: The result of the study are as follows: The average item score for the health promoting lifestyle was 2.46, the highest score on the subscale was interpersonal support(M=2.83). A significant difference between age, education level, income, experience of smoking, alcohol, exercise, and health promoting lifestyle were found. Stepwise multiple regression analysis revealed that the most powerful predictor of health promoting lifestyle was social support(55%). Conclusion: Social support accounted for 54% of the variance in health promoting lifestyle in the elderly women. Therefore, health promoting programs that increase social support should be developed to promote a healthy lifestyle of the elderly women.