• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1859-1863
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• 2007

A new type of a fretting wear tester has been designed and developed in order to simulate the actual vibration behavior of a nuclear fuel rod for springs/dimples in room temperature. When considering the actual contact condition between fuel rod and spring/dimple, if fretting wear progress due to the flow-induced vibration (FIV) under a specific normal load exerted on the fuel rod by the elastic deformation of the spring, the contacting force between the fuel rod and dimple that were located in the opposite side should be decreased. Consequently, the evaluation of developed spacer grids against fretting wear damage should be performed with the results of a cell unit experiments because the contacting force is one of the most important variables that influence to the fretting wear mechanism. Therefore, it is necessary to develop a new type of fretting test rig in order to simulate the actual contact condition. In this paper, the development procedure of a new fretting wear tester and its performance were discussed in detail.

• Korean Journal of Community Nutrition
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• v.3 no.2
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• pp.308-316
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• 1998

This study was made to find out the relationship between the eating attitude influenced by an eating disorder and nutritional knowledge among 441 female college students. A self-report questionnaire was used, and the summary of the results are as follows : Almost all of the surveyed female college students were in criteria of standard weight, however they regard themselves more obese than what their actual body shape normally shows. The correlation between perceived body shape and the eating attitude influenced by an eating disorder turned out to be high(p<0.001). The significant level of correlation between the perceived body shape and the eating attitude test-26(EAT-26) scores showed much higher than that obtained between actual shape, degree of obesity and eating attitude test-26(EAT 26) scores(p<0.001). There was no significant level of correlation between the defree of obesity and the average score of nutritional knowledge obtained out of the total questionnaire, however it showed significant level of correlation between macronutrient and roughage(p<0.05), fat and calorie requirement(p<0.01). There was significant correlation among perceived body shape, actual weight and eating attitude influenced. by an eating disorder. Thus the correct perception of body shape turned out to be an important factor in obtaining the desirable eating attitude and adequate nutritional knowldege.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.4
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• pp.123-128
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• 2010

In this paper, in order to reduce the electric disaster damage which is caused by with electric equipment of traditional markets, we developed cabinet panel and the electric safety monitoring system which is able to monitor the electrical equipments condition(over current, leakage, arc, WH, electrical fire factor etc.) at traditional markets. We constructed Test-bed for testing reliability of electric safety monitoring system and the actual condition investigation about electrical equipment of traditional market. This paper will be used with the data for an actual demonstration project after reinforcing problems which are occurred to operation of traditional market actual loads.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.7
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• pp.99-109
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• 2012

Sub-station, key equipment in electric power infrastructure, are being exposed to increasing risk of hacking. For this, soft redundancy sub-station system needs to be formulated with automatic restoration mechanism. For this it is important to assess the reliability of the applicable range of data that are used in actual system operation, as well as the methods and findings of the tests. At the same time performance of soft redundancy system and total security mechanism, which are aligned for the protection of the sub-station, need to be tested. For testing the above-mentioned, this paper presented a viable formation of a soft redundancy practical VPN system within a panel to protect the latter from hacking or cracking incidences, and conducts a test to check if the considered system actually serves the protection function in the actual operation setting, gathering evidence from the data from the testing of the actual performance of the system as well as of emergency scenario simulation operations. Because tested soft-redundancy & restorative sub-station system is expected to be widely applicable for various cases such as Smart-grid or electricity IT system, where VPN with enhanced level of security is required.

• The Journal of Korean Association of Computer Education
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• v.15 no.6
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• pp.53-64
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• 2012

This study was to compare and analyze actual conditions and awareness of high school students' mobile learning. Survey was used as a research method and percentile, t-test and F-test were conducted for the statistical analyses. Results revealed that in the case of actual conditions on mobile device and mobile learning, slight differences were shown in various sub-variables, depending on independent variables (gender, grade, track); year 2010 can be the most important year for the mobile learning; high school students seldom utilize mobile learning in a small piece of time; mobile learning using Apps was not widespread yet. In the case of awareness of mobile learning, statistically significant differences were found in the use capacity of mobile devices, the increase of learning performance, and the continual interests of mobile devices.

• The Research Journal of the Costume Culture
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• v.12 no.1
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• pp.90-103
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• 2004

The purpose of the present study was to investigate images pursued and purchase behaviors for clothing as determined by self-image. Data were collected through a self-administered questionnaire survey from March 3 to March 11, 2003 from 600 female students attending universities in Seoul; 514 were used for the data analysis. Data were analyzed by chi-square analysis, t-test, ANOVA, correlation analysis, tics, cluster analysis and Duncan's multiple range test. Self image was defined six factors: social image, gay image, intellectual image, girlish image, iron nerves image, image like a man and was classified three group avail of six factor: commonness type, social brilliance type, immature boldness type. The results showed significant differences in images of actual clothing worn by self and in the clothing image pursued among the groups determined by the self image. Significant differences were also found in clothing purchase behaviors such as monthly clothing expenditure, shopping frequency, store types, and the clothing items often used for expressing self-image among the groups divided by self-image.

• Textile Coloration and Finishing
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• v.34 no.4
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• pp.250-260
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• 2022

In this research, a high-elasticity acrylic emulsion binder with core-shell polymerization and self-crosslinking system is mixed with a flame-retardant water-dispersed polyurethane (PUD) binder. In addition, finite element analysis was conducted through virtual engineering software ANSYS by applying three representative nonlinear material models. The most suitable nonlinear material model was selected after the relative comparison between the actual experimental values and the predicted values of the properties derived from simulations. The selected nonlinear material model is intended to be used as a nonlinear material model for computational simulation analysis that simulates the experimental environment of the vibration test (ASTM E1399) and the actual fire safety test (ASTM E1966). When the mass fraction of thermally expandable graphite was 0.7%, the thermal and physical properties were the best. Among the nonlinear material models, the simulation result of the Ogden model showed the closest value to the actual result.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.3 no.1
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• pp.1-9
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• 2007

A steady-state simulation model for Dual-Source Heat Pump(DSHP) of 8RT was presented. A Dual-Source Heat Pump(DSHP) has been designed to make up for the conventional air source heat pumps. The performance evaluation has been conducted under internal standard test conditions such as ISO-13256-1 and KS C 9306. However, as test conditions such as entering water, indoor and outdoor air conditions could not be controlled to satisfy the standard test conditions in outdoor tests, a series of experiments have been conducted with the actual test conditions. Then, computer models for DSHP could be used for the standard condition have developed using EES program. The model was developed from basic thermodynamic principles and heat transfer relations. Most of the parameters were obtained with EES from the actual catalog data. The simulation results were in good agreement with the experiments.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.5
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• pp.157-164
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• 2001

This paper performs static and dynamic tests of a multi-leaf spring and a tapered leaf spring to investigate their hysteretic characteristics. In the static test, trapezoidal input load is applied with 0.1Hz excitation frequency and with zero initial loading conditions. In the dynamic test, sinusoidal input load is applied with five excitation amplitudes and three excitation frequencies. In these tests, static and dynamic hysteretic characteristics of the multi-leaf spring and the tapered leaf spring are compared, and, the effects of excitation amplitudes and frequencies on dynamic spring rate are also shown. In this paper, actual vehicle tests are performed to study the effects of hysteretic characteristics of the large-sized truck's handling performance. The multi-leaf spring or the tapered leaf spring is used in the front suspension. The actual vehicle test is performed in a double lane change track with three velocities. Lateral acceleration, yaw rate and roll angle are measured using a gyro-meter located at the mass center of the cab. The test results showed that a large-sized truck with a tapered leaf spring needs to have an additional apparatus such as roll stabilizer bar to increase the roll stabilizer due to hysteretic characteristics.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.8
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• pp.112-119
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• 2004

This paper develops a computer model of a cabover type large truck for estimating the effects of the mounted method of frame on handling performance. The computer model considers two mounted methods of frame; flange mounted and web mounted. Frame is modeled by finite elements using MSC/NASTRAN in order to consider the flexibility of frame. The reliability of the developed computer model is verified by comparing the actual vehicle test results with the simulation results. The actual vehicle test is performed in a double lane change course, and lateral acceleration, yaw rate, and roll angle are measured. To estimate the effects of the mounted method of frame on handling performance, simulations are performed with the flange mounted and web mounted frame. Simulation results show that the web mounted frame＇s variations of roll angle, lateral acceleration, and yaw rate are larger than the flange mounted frame＇s variations, especially in the high test velocity and the second part of the double lane course. Also, simulation results show that the web mounted frame＇s tendencies of roll angle, lateral acceleration, and yaw rate advance the flange mounted frame＇s tendencies, especially in the high test velocity and the second part of the double lane course.