• Journal of the Korean Magnetics Society
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• v.20 no.6
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• pp.239-243
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• 2010

This paper deals with the optimum design criteria for the premium efficiency of 250 kW traction induction motor, using response surface methodology (RSM) and finite element method (FEM). The focus of this paper is found firstly a design solution through the comparison of torque according to rotor bar shape, rotor dimensions variations. And secondly a mixed resolution with central composite design (CCD) is introduced and analysis of variance (ANOVA) is conducted to determine the significance of the fitted regression model. The proposed procedure allows to be optimized the rotor copper bar shape, rotor slot, rotor dimensions starting from an existing motor or a preliminary design.

• The Research Journal of the Costume Culture
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• v.6 no.4
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• pp.120-135
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• 1998

The purpose of this study were to develop the taxonomy of apparel buying decision approaches and to identify the relationships between the apparel buying decision approaches and the situational characteristics. Data were collected via a questionnaire developed on the previous studies and the focus interview from 425 female college students living at Pusan, and analyzed by Factor Analysis, Cluster Analysis, Analysis of Variance, and Discriminant Analysis. Results indicated that apparel buying decision approaches consisted of eight dimensions and situational characteristics of affecting a particular apparel buying decision approaches were composed of three or five factors. The four types of apparel buying decision approaches were derived by Cluster Analysis and ANOVA: Recreational Shoppers, Brand Conscious Shoppers, Quality Conscious Shoppers, and Apathetic Shoppers. The findings revealed some patterns that were similar to previous studies and was useful to marketing managers who can view their customer segments in terms of the types in the taxonomy. Further, it provided a tool by which sales representatives can develop adaptive selling approaches based on a small set of buying situation and corresponding apparel buying decision approaches.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.3
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• pp.191-198
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• 2007

Marine accidents are increasing as time goes on, in spite of lots of efforts are given. Marine accidents can be classified 3 categories those are ship's condition, navigator's condition and weather condition. In this paper, statistical analysis were carried using marine accidents data from 1997 to 2006. In order to analyze accident rate by time zone, ship's speed and finding distant, SPSS variance analysis was carried out. Results are followed. There was significant difference between time zone 20${\sim}$04 hours and other time zones. The accident rate in daytime was bigger than that at night. In case of the speed at collision, the speed of 5${\sim}$10 knot has significant difference to other speed cases. In finding distant cases, the case of less than 1 mile has significant difference to other distant cases.

• Human Ecology Research
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• v.53 no.6
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• pp.655-665
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• 2015

This study classified respondents by food-lifestyle and investigated differences in diet-related attitudes and demographic variables among food-lifestyle groups. Diet-related attitudes consisted of variables such as interest in diet, trial number of diet, diet period, weight loss, diet motivation, verification of products approved by the Ministry of Food and Drug Safety, verification of manufacturer's reliability, examination of damage cases and side effects, and awareness of consumer protection law. This study administered a questionnaire survey to adults between the ages of 20 and 39 who lived in Daegu and Uijeongbu from November 17th to December 14th 2014. Data collected from 293 respondents were analyzed using descriptive statistics, factor analyses, cluster analysis, analysis of variance (ANOVA) and chi-square tests. Four clusters (passive eating habit group, active eating habit group, convenience oriented group, and taste and health oriented group) were developed according to four factors of food-lifestyle (health-conscious, popularity-seeking, taste-seeking, convenience-seeking). The results of the ANOVA and chi-square tests indicated significant differences in interest in diet, awareness of consumer protection law, verification of products approved by the Ministry of Food and Drug Safety, verification of manufacturer's reliability, examination of damage cases and side effects, gender, education levels and household monthly income levels among food-lifestyle groups.

• Advances in materials Research
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• v.6 no.1
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• pp.79-91
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• 2017

In the present work, a design of experiment (DOE) technique using Taguchi method, has been applied to optimize the properties of ODS tungsten heavy alloys(WHAs). In this work Taguchi method involves nine experiments groups for four processing parameters (compaction pressure, sintering temperature, binding material type, and oxide type) with three levels was implemented. The signal-to-noise (S/N) ratio and analysis of variance (ANOVA) were employed to obtain the optimal process parameter levels and to analyze the effect of these parameters on density, electrical conductivity, hardness and compressive strength values. The results showed that all the chosen factors have significant effects on all properties of ODS tungsten heavy alloys samples. The density, electrical conductivity and hardness increases with the increase in sintering temperature. The analysis of the verification experiments for the physical properties (density and Electrical conductivity) has shown that Taguchi parameter design can successfully verify the optimal parameters, where the difference between the predicted and the verified values of relative density and electrical conductivity is about 1.01% and 1.15% respectively.

• Korean Journal of Rural Living Science
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• v.7 no.2
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• pp.139-152
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• 1996

The objectives of this study are : (1) to measure the level of economic stress perception in Korean farm households. (2) to identify the effects of related variables such as socio-demographic variables and economic stability. The data from 505 farm households' wives was analyzed using statistical methods such as frequency, correlation, oneway ANOVA, lease significant difference test, and stepwise multiple regression. The major findings are as follows : The mean value of economic stress perception on the 505 wives was 33.5 points out of a possible 100. Among 3 subsectors, income stress perception had highest score. Socio- demographic variables such as family size, type of farm household, financial manager, debt, credit . grant assistant, wife's age, and educational level of the wife had a significant difference on the economic stress perception of wives in the ANOVA analysis. So did the objective and subjective evaluation of economic stability. As a result of multiple regression analysis, economic stability, debt presence, and wife age were verified explaining 23% of the variance of economic stress perception. Therefore, it can be said that farm wives had relatively high economic stress perception in the case of low economic stability, getting into debt and low age.

• Laser Solutions
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• v.8 no.3
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• pp.11-19
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• 2005

In automotive industry, light weight vehicle is one of issues because of the air pollution and the protection of environment. Therefore, automotive manufacturers have tried to adopt light materials such as aluminum alloy to production line. Aluminum welding using laser has some advantages high energy density and high productivity. It is very important to understand weld characteristic according to welding condition in order to determine the possibility of application to car body. In this study, Nd:YAG laser welding of 5182 aluminum alloy with filler wire AA5356 was carried out through experimental design according to wire feed rate, laser power and welding speed. Weld bead shape in terms of cross section photo, bead with, height of reinforcement and penetration depth and mechanical property in terms of tensile strength and formability was investigated. Analysis of variation (ANOVA) was performed to know the effect of weld parameter for weldability, laser power was statistically most significance factor of three variables.

• Corrosion Science and Technology
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• v.21 no.4
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• pp.314-324
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• 2022

The objective of this investigation was to indentify major factors affecting surface roughness among various parameters of electropolishing process using the design of an experiment method (full factorial design) for UNS S31603. Factors selected included electrolyte composition ratio, applied current density, and electrolytic polishing time. They were compared through analysis of variance (ANOVA). Results of ANOVA revealed that all parameters could affect surface roughness, with the influence of electrolyte composition ratio being the highest. As a result of surface analysis after electropolishing, the specimen with the deepest surface damage was about 35 times greater than the condition with the smallest surface damage. The largest value of surface roughness after electropolishing was higher than that of mechanical polishing due to excessive processing. On the other hand, the smallest value of surface roughness after electropolishing was 0.159 ㎛, which was improved by more than 80% compared to the previous mechanical polishing. Taken all results together, it is the most appropriate to perform electrolytic polishing with a sulfuric acid and phosphoric acid ratio of 3:7, an applied current density of 300 mA/cm², and anelectrolytic polishing time of 5 minutes.

• PNF and Movement
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• v.18 no.3
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• pp.425-433
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• 2020

Purpose: The purpose of this study was to investigate the effect of 7Hz vibration on the thickness of the rectus femoris, medial femur, rectus femoris tendon, and Achilles tendon. Methods: The statistical methods before and after working around the average value of each of the legs included repeated measures ANOVA. The subjects were 26 males residing in the N area, and we measured the change in muscle thickness and tendon thickness before, four weeks, and eight weeks after the experiment in two groups of 13 subjects each. The analysis method was a two-way repeated measurement variance analysis (ANOVA) with a significance level of 0.05 Results: The rectus femoris, medial broad muscle, rectus femur, and Achilles tendon showed significant increases in the interaction between the periods as well as between the periods and groups (p < 0.05). Conclusion: As a result of this study, the 7Hz vibration had a positive effect on the thickness of the rectus femoris and the vastus medialis muscle as well as the thickness of the rectus femoris tendon and Achilles tendon. It is expected to be used as basic data for vibrational exercises in the future studies and is expected to be used as an exercise to strengthen the leg muscles and tendons.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.1
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• pp.33-40
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• 2010

In this research, the effects for surface Improvement of plasma ion implanted carbide endmill tools were observed by measuring cutting forces and tools wear affecting surface roughness in high speed cutting. From the 2nd ion mass analysis, the oxidation layer was found to be built up by sputtering. The residual gas contamination of oxygen was found to be contained impurities in nitrogen gas. The plasma implanted ion was found to be spreaded, especially the nitrogen was implanted up to 150nm depth as impressed voltage and ion implanting time. It is analyzed as bring surface improvement by spreading deeply forming oxidation on surface. The factors in Analysis of Variance(ANOVA) about mutuality cause reference of cutting force. The cutting force Fx is affected by the interaction of spindle rpm and federate, the cutting force Fy is influenced by spindle rpm and time injected ion, and cutting force Fz is affected by the interaction of impressed voltage and feedrate. Also, it was found that the cutting forces of implanted tools become lower and the surface roughness is improved by the effect of nitrogen according to the implantation.