• International Journal of Vascular Biomedical Engineering
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• v.3 no.2
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• pp.17-24
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• 2005

The main purpose of our study is to propose a new methodology to develop the multi-parametric measure including linear and nonlinear measures of heart rate variability diagnosing cardiovascular disease. We recorded electrocardiogram for three recumbent postures; the supine, left lateral, and right lateral postures. Twenty control subjects (age: $56.70{\pm}9.23$ years), 51 patients with angina pectoris (age: $59.98{\pm}8.41$ years) and 13 patients with acute coronary syndrome (age: $59.08{\pm}9.86$ years) participated in this study. To develop the multi-parametric measure of HRV, we used the multiple discriminant analysis method among statistical techniques. As a result, the multiple discriminant analysis gave 75.0% of goodness of fit. When the linear and nonlinear measures of HRV are individually used as a clinical tool to diagnose cardiac autonomic function, there is quite a possibility that the wrong results will be obtained due to each measure has different characteristics. Although our study is a preliminary one, we suggest that the multi-parametric measure, which takes into consideration the whole possible linear and nonlinear measures of HRV, may be helpful to diagnose the cardiovascular disease as a diagnostic supplementary tool.

• Journal of Korean Public Health Nursing
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• v.3 no.1
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• pp.61-66
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• 1989

The purpose of this study was to investigate blood pressure and its related factors of middle-aged women in Korea. For the collection of data, 410 women aged between 45-54 were selected through stratified sampling techniques at urban and rural areas in Korea. They were interviewed from Oct. 15 through Nov. 14 by use of questionare. Descriptive statistical methods, multiple stepwise regression methods and multiple discriminant analysis by S.P.S.S. were used to analyze the data. The obtained result are summarized as follows. 1. Systolic B.P was 119.2 mmHg. mean pressure, Diastolic B.P. was 77.7 mmHg. mean pressure. 2. Systolic B.P. was related with the area and the ownership of house; it was accepted (P<05) 3. The most important factor affecting the B.P of middle-aged women were weight It was related with systolic pressure(0.176) and diastolic pressure(0.157) That is, this study showed that for the middle-aged women(45-54 yrs.), health education about weight control which can prevent ascending B.P should be demanded.

• Agribusiness and Information Management
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• v.3 no.1
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• pp.11-22
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• 2011

This study describes the development of a web-based system that collects all data generated in the research conducted to set pre-harvest residue limits (PHRLs) for agricultural product safety control. These data, including concentrations of pesticide residues, limit of detection, limit of quantitation, recoveries, weather charts, and growth rates, are incorporated into a database, a regression analysis of the data is performed using statistical techniques, and the PHRL for an agricultural product is automatically computed. The development and establishment of this system increased the efficiency and improved the reliability of the research in this area by standardizing the data and maintaining its accuracy without temporal or spatial limitations. The system permits automatic computation of the PHRL and a quick review of the goodness of fit of the regression model. By building and analyzing a database, it also allows data accumulated over the last 10 years to be utilized.

• Journal of Welding and Joining
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• v.14 no.4
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• pp.33-42
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• 1996

In recent years there has been a significant growth in the use of the automated and/or robotic welding system, carried out as a means of improving productivity and quality, reducing product costs and removing the operator from tedious and potentially hazardous environments. One of the major difficulties with the automated and/or robotic welding process is the inherent lack of mathematical models for determination of suitable welding process parameters. Partial-penetration, single-pass bead-on-plate welds were fabricated in 12mm AS 1204 mild steel flats employing five different welding process parameters. The experimental results were used to develop three empirical equations: curvilinear; polynomial; and linear equations. The results were also employed to find the best mathematical equation under weld bend width to assist in the process control algorithms for the Gas Metal Arc Welding(GMAW) process and to correlate welding process parameters with weld bead width of bead-on-plates deposited. With the help of a standard statistical package program. SAS, multipe regression analysis was undertaken for investigating and modeling the GMAW process, and significance test techniques were applied for the interpretation of the experimental data.

• Journal of the Korean Home Economics Association
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• v.40 no.7
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• pp.25-40
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• 2002

The purpose of this study was to examine the relationships between child's emotional intelligence and stress according to child's sex. The subjects for this study were 380 children of 5-6th grade selected from elementary schools in Busan. Kwak's questionnaires(1994) on child's emotional intelligence and Han, Mi-Hyun's questionnaires(1996) on child's stress were used. Statistical techniques such as Manoya, Pearson's correlation, canonical were used. The results were as follows : (1) According to sex, there were significant differences in child's emotional intelligence and stress. The girls showed higher emotional expression, emotional empathy, emotional control, and the friend-related stress than boys. The boys showed higher parent-related stress than girls. (2) There were significant negative correlations between child's emotional intelligence and stress. The children who got higher emotion intelligence perceived lower stress. (3) Among five dimensions of emotional intelligence for boy, the effective variable was emotional utilization. And among six dimensions of stress, the effective variables were home-environment stress and school-related stress. Among fine dimensions of emotional intelligence for girl, the effective variables were emotional expression and emotional recognition. And among six dimensions of stress, the effective variables were friend-related stress and parent-related stress.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.4
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• pp.61-71
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• 1987

Accelerated strength testing is a available method for quality control of concrete. This paper presents the improved hot water ($70^{\circ}C$) methods and discusses how these methods can be adapted for predicting 28 day strength. The strength results have been analyzed by statistical techniques and correlation between early and 28 day strength are showed by prediction line. The test results show that the methods proposed in this paper are usable to predict the potential quality of concrete with low variation and good relationship between two strengths.

• Journal of the Korean Institute of Gas
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• v.11 no.3
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• pp.56-63
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• 2007

These days, needs and wants of the customers are getting diversified and the market is also changing rapidely. Many organizations are now attempting change and innovation activities to improve products and service quality. This study was performed to apply 6 sigma tools for the efficient repair management of city gas supply equipment. Vital few factors, RISK factors, sigma values, root causes. and solutions were derived by 6 sigma tools. We are performing statistical process control for the new process. Six sigma for city gas supply equipment safety management enabled to improve the business management for efficiency by reducing variation and eliminating cost for quality.

• Current Applied Physics
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• v.18 no.11
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• pp.1174-1181
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• 2018

In nanomagnetism, one of the crucial scientific questions is whether magnetic behaviors are deterministic or stochastic on a nanoscale. Apart from the exciting physical issue, this question is also of paramount highest relevance for using magnetic materials in a wealth of technological applications such as magnetic storage and sensor devices. In the past, the research on the stochasticity of a magnetic process has been mainly done by macroscopic measurements, which only offer ensemble-averaged information. To give more accurate answer for the question and to fully understand related underlying physics, the direct observation of statistical behaviors in magnetic structures and magnetic phenomena utilizing advanced characterization techniques is highly required. One of the ideal tools for such study is a full-field soft X-ray microscope since it enables imaging of magnetic structures on the large field of view within a few seconds. Here we review the stochastic behaviors of various magnetic processes including magnetization reversal process in thin films, magnetic domain wall motions in nanowires, and magnetic vortex formations in nanodisks studied by full-field soft X-ray microscopy. The origin triggering the stochastic nature witnessed in each magnetic process and the way to control the intrinsic nature are also discussed.

• Journal of Wellbeing Management and Applied Psychology
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• v.7 no.3
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• pp.55-65
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• 2024

Purpose: This study aims to analyze the status and realities of mental health counseling experiences among adults using the 2022 National Health and Nutrition Examination Survey(NHNES) data. The goal is to provide policy recommendations for enhancing mental health services. Research Methods: Utilizing secondary data analysis of the 2022 survey conducted by the Korea Disease Control and Prevention Agency(KDCPA), this study applied statistical techniques including descriptive statistics, chi-square tests, and logistic regression to evaluate counseling experiences based on age, gender, residential area, and income levels. Results: The study included 5,256 participants, with the highest proportion being those aged 60-69 (21.3%) and the lowest aged 19-29 (11.7%). Females constituted 56.5% of the sample, while males made up 43.5%. Older adults (60-69 and 70+) had significantly lower counseling experience rates compared to younger adults (19-29). Females had higher counseling experience rates than males, indicating gender differences in mental health service utilization. Urban residents had higher counseling experience rates than rural residents, suggesting better access to mental health services in urban areas. Lower income levels were associated with higher counseling experience rates, highlighting the need for targeted mental health support for economically disadvantaged groups. Conclusions: The study recommends developing age-specific, gender-sensitive, and regionally tailored mental health programs to improve accessibility and effectiveness. Additionally, policies should focus on enhancing mental health support for low-income individuals to address the socioeconomic disparities in mental health service utilization.

• Journal of the Korea Society for Simulation
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• v.18 no.3
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• pp.103-112
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• 2009

In a nuclear power plant (NPP), periodic sensor calibrations are required to assure sensors are operating correctly. However, only a few faulty sensors are found to be calibrated. For the safe operation of an NPP and the reduction of unnecessary calibration, on-line calibration monitoring is needed. In this paper, principal component-based Auto-Associative support vector regression (PCSVR) was proposed for the sensor signal validation of the NPP. It utilizes the attractive merits of principal component analysis (PCA) for extracting predominant feature vectors and AASVR because it easily represents complicated processes that are difficult to model with analytical and mechanistic models. With the use of real plant startup data from the Kori Nuclear Power Plant Unit 3, SVR hyperparameters were optimized by the response surface methodology (RSM). Moreover the statistical techniques are integrated with PCSVR for the failure detection. The residuals between the estimated signals and the measured signals are tested by the Shewhart Control Chart, Exponentially Weighted Moving Average (EWMA), Cumulative Sum (CUSUM) and generalized likelihood ratio test (GLRT) to detect whether the sensors are failed or not. This study shows the GLRT can be a candidate for the detection of sensor drift.