• Journal of Electrical Engineering and Technology
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• v.11 no.6
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• pp.1628-1633
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• 2016

This paper derives an effective shape of the ferromagnetic pole pieces (low-speed rotor) for the reduction of transmission torque ripple in a magnetic-geared machine based on a Box-Behnken design (BBD). In particular, using a non-linear finite element method (FEM) based on 2-D numerical analysis, we conduct a numerical investigation and analysis between independent variables (selected by the BBD) and reaction variables. In addition, we derive a regression equation for reaction variables according to the independent variables by using multiple regression analysis and analysis of variance (ANOVA). We assess the validity of the optimized design by comparing characteristics of the optimized model derived from a response surface analysis and an initial model.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.380-385
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• 2001

The paper presents a new multidisciplinary design optimization architecture using optimal sensitivity and coordination of interdisciplinary design variables. Original design problem is decomposed into a number of sub-problems that represent individual engineering analysis. The coupled effects between sub-problems are computed by interdisciplinary design variables. System level coordination is determined by optimal parameter sensitivity calculated by finite difference method. The proposed. MDO strategy is applied to a simplified model of rotorcraft blade design associated with structures and aerodynamic disciplines.

• Journal of Preventive Medicine and Public Health
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• v.15 no.1
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• pp.213-217
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• 1982

Self sensing symptoms were. surveyed by interview from the workers using lacquer-thinner(Male 35, Female 28). And the data was converted to point. Independent variables were state of the medication, education, alcohol drinking, smoking, living and past occupational history. Dependent variable was the point. The relationship between independent variables and the depenent variable was studied. The result of the study were briefly summarized as below. 1. The difference of point between sex and medication statement was significant by statistical test. 2. Age and past occupational history were not important variables. 3. The Multiple Stepwise Regression Equation obtained by this study was not useful.

• MALSORI
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• no.48
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• pp.19-33
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• 2003

Sasang Constitutional Medicine, a branch of traditional Korean medicine, believes that the health of human beings can be promoted by taking advantage of the fact that people have different constitutions. It utilizes the characteristics in human voice to diagnose the constitution of the patients. This study aims at establishing the relationship between Sasang constitutions and their corresponding voice characteristics by investigating source-related variables. Voice recordings of 23 patients from three different constitutions were obtained whose constitutions had been already diagnosed by the experts in the fields. Fundamental frequency related variables (average pitch, maximum/minimum pitch, pitch range), phonation type, speaking tempo were measured and analyzed for each group. The phonation type seemed to be a possible candidate for a successful variable to determine constitution. No statistically significant relationship was manifested between other variables and constitutions. Despite its failure to firmly establish the relationship between voice and constitutions, the current study suggests that future research should include not only source-related variables

• Journal of Korean Society for Quality Management
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• v.33 no.3
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• pp.135-148
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• 2005

This paper considers a six sigma project for reducing the project costs through project risk management. The project follows a disciplined process of five phases: define, measure, analyze, improve, and control. A risk management process map is used to identify process input and output variables. Seven key process input variables are selected by using C&E diagram and X-Y matrix and finally four vital few input variables are selected by the related statistical analysis. The optimum alternatives of the vital few input variables are obtained by the method of PUGH matrix. The process is running on control plan and we obtained substantial project cost reductions in early stage of the control phase.

• Journal of KSNVE
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• v.8 no.2
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• pp.283-288
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• 1998

If one wants to control the noise from a duct, then one must have sufficient number of sensors and actuators so that the control system is observable and controllable. A number of sensors and actuators for control of radiating noise from a duct have to be incorporated with the number of modes which one wants to control. These considerations motivated the present study that considers a control system which has less microphones and actuators than required. In this work, by theoretical analysis and numerical simulation, the control performance and robust reliability of such a kind of control system is investigated in terms of sound-field variables and control system variables. Then the possibility of implementation of the robust radiation power control system is verified by theoretical analysis and numerical simulation. In addition, the control performance of the control system is verified by experiment.

• Journal of Korean Institute of Industrial Engineers
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• v.30 no.4
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• pp.267-276
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• 2004

Much of previous attention on researches of the decision tree focuses on the splitting criteria and optimization of tree size. Nowadays the quantity of the data increase and relation of variables becomes very complex. And hence, this comes to have plenty number of unnecessary node and leaf. Consequently the confidence of the explanation and forecasting of the decision tree falls off. In this research report, we propose some decision tree algorithms considering the interaction of predictor variables. A generic algorithm, the k-1 Algorithm, dealing with the interaction with a combination of all predictor variable is presented. And then, the extended version k-k Algorithm which considers with the interaction every k-depth with a combination of some predictor variables. Also, we present an improved algorithm by introducing control parameter to the algorithms. The algorithms are tested by real field credit card data, census data, bank data, etc.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.11
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• pp.1482-1494
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• 2004

This study identified convergent validity and discriminant validity of measurement variables by factor analysis using Spss program and tested covariance measurement model including latent variables such as the website attributes (interactivity, search and visual information of website), shopping values(utilitarian and hedonic value) and attitude toward website by AMOS program. The data were collected from a sample of 271 internet shopper of university students(male: 82, female: 189). They visited the website for apparel shopping and, after searching a casual clothing which they wanted to buy, requested to answer the questionnaire. The results were as follows: Variables that reduce validity were deleted in the several steps of factor analysis and initial measurement model testing. Final measurement model was constructed by valid variables was accepted. This measurement model will be input for testing causal research model that can explain how attributes of the website influences on consumer attitude toward the website.

• Journal of the Korean Home Economics Association
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• v.37 no.2
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• pp.85-98
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• 1999

The purpose of this study is to identify the preferences for care type among the elderly and to analyze contributing variables. The sample in this study are 485 elder people who are age 55 and over. The independent variables are divided into five factors according to their characteristics, and the dependent variables fall into two categories of private and public care types. The descriptive statistics and Logistic Regression method are employed for the analysis. The results can be summarized as follows. The elderly prefer individual care paid for by their own support to the other types like the care by children or institution. However, the elderly stiff like and expect family care by their children. The variables that haute affected the preferences of the care types among the elderly are whether they are employed or not, household's the amount of debt, whether they currently live with the oldest child, their level of self esteem and their degree of satisfaction in life. The results show that the elderly don't have various wants or alternatives to their care and regard public care as negative support for the financially incapable or the elderly who have no relatives.

• Journal of the Korean Home Economics Association
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• v.33 no.3
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• pp.31-42
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• 1995

The purpose of this study was to investigate the effect of parent-bonding patterns and family environmental variables on adolescents' depression. the subjects were college students in Taegu, An-dong, and Pusan city. the adolescents' depression, parent-bonding style, and family environmental variables were measured by BDI(Beck Depression Inventory), PBII(Parent-Bondning Instrument), Family environmental scale. The data were analyzed by Frequency and Regression analysis. The results were as follow. First, in parent-bonding styles, the frequencies of mother's care and overprotection wee higher than those of father's Second, a half of all subjects were under the state of depression ranging from low level to high level. Third, the satisfaction of family life amomg family environmental variables had the most effects on PBI. fourth, the degree of adolescents' depression was affected by family satisfaction, parents' occupation, monthly income, and mother's overprotection n parent-bonding style and family environmental variables.