• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.6
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• pp.1-6
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• 2005

In domestic replacement tire market, imported tires are increasing condinuously. Because there is no institute officially investigating tire safety and performance, domestic drivers can be exposed to defective tires with no regulations. In this study we performed investigation of replacement tire market status and amount of imported tires. Over $90\%$ of imported tires are for passenger car and the number of total imported tires is increasing in recent years. Low price tires imported from Southeast Asia and China are selected to evaluate quality level. Basic inspection, indoor test, outdoor test, material test are conducted to evaluate the selected tires and compared with tires of domestic maker. From test results quality level of the selected tires could be found.

• Journal of the Korean Home Economics Association
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• v.33 no.4
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• pp.25-35
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• 1995

The objectives of this study were : 1) to investigate the socio-demographic and housing characteristics, 2) to evaluate the present conditions of residential environment, 3) and to analysis the differences of residential environmental evaluation according to the characteristics of low-income families. Questionnaire survey method were used in this study. questionnaire were administrated by 264 household of low-income families in Taejon area. Data were analyzed by SPSS PC computer package. The statistics were frequencies, percentage, t-test, F-test and Ducan's multiple range test. The major findings were as follows; low income families evaluated all of their residential environment at lower, especially the worst of all was the comfortable environment outdoor. there were significant differences in evaluation of residential environment according to the housing characteristics of low income families. The results of this study can be used as basic information for housing p;an and policy for low income families in Taejon area.

• Journal of Electrical Engineering and Technology
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• v.11 no.4
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• pp.961-968
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• 2016

The non-uniform distribution of contamination on insulator surface has appreciable effects on flashover voltage, and corresponding researches are valuable for the better selection of outdoor insulation. In this paper, two typical types of porcelain and glass insulators which are widely used in ac lines were taken as the research subjects, and their corrections of AC flashover voltage under non-uniform pollution were studied. Besides, their flashover characteristics under different ratio (T/B) of top to bottom surface salt deposit density (SDD) were investigated, including the analysis of flashover voltage, surface pollution layer conductivity and critical leakage current. Test results gave the modified formulas for predicting flashover voltage of the two samples, which can be directly applied in the transmission line design. Also, the analysis delivered that, the basic reason why the flashover voltage increases with the decrease of T/B, is due to the decrease of equivalent surface conductivity of the whole surface and the decrease of critical leakage current. This research will be of certain value in providing references for outdoor insulation selection, as well as in proposing more information for revealing pollution flashover mechanism.

• Journal of Sport and Applied Science
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• v.7 no.4
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• pp.7-12
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• 2023

Purpose: The purpose of this study is to compare and analyze power and agility, which are factors that affect performance, by dividing adult fin swimmers into groups by male and female careers, and use them as basic data for improving performance during fin swimmer guidance and training. Research design, data, and methodology: Accordingly, 21 fin swimmers were selected and they were divided to four groups by gender and career to conduct experiments. Power and agility, which are factors related to performance of fin swimmers, were measured. Independent sample T-Test was conducted to verify differences between groups. Results: As a result of this study, there was no statistically significant difference in power and agility by the careers of male and female athletes. Conclusion: The results of this study can be used as basic data for organizing training programs suitable for the gen-der of fin swimmers and basic data for the guidance and training of fin swimmers. In future follow-up studies, based on the results of this study, it is expected that follow-up studies should be con-ducted to improve detailed performance according to age, fin swimming events, and gender. Further implications were discussed.

• Journal of the Society of Naval Architects of Korea
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• v.60 no.4
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• pp.256-265
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• 2023

This paper describes the results of the development of the submarine Free Running Model (FRM). First, the goal of development was set based on the test conditions and the test environment, and the system was obtained accordingly. The target submarine, Joubert BB2 submarine, was selected with a scale of 18.35 in accordance with the development goal. In order to conduct a submarine FRM test underwater, where communication is impossible, the FRM must operate at least semi-autonomously. For this purpose, an Extended Kalman Filter (EKF) based underwater integrated navigation system and control system using a sailplane and an X-shaped sternplane were designed respectively. In addition, a ballast system was designed to enable the model to float to the water surface in case of an emergency. To verify its propulsion, navigation, and control performance, the FRM tests were conducted in both indoor and outdoor basins. As a result, the relationship between propeller RPM and vehicle speed was derived, and it was confirmed that the navigation and control performance met the target value.

• 한국터널공학회:학술대회논문집
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• 2005.04a
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• pp.335-340
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• 2005

Recently, According to increased tunnel accident, a matter of concern in tunnel fire safety is on an interesting trend. In case of tunnel fire, Evacuation is a primary factor for refugee safety. Therefore safety measures should be taken to increase capability of evacuation. Evacuation walking speed and characteristics of movement in tunnel is differ from building or outdoor site so, these characteristics must be considered in tunnel safety planning. In this study has performed to evaluate the smoke movement and characteristics of evacuation by full-scale test method. and aimed for basic data establishment in characteristics of evacuation for tunnel safety system design.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2006.11a
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• pp.488-491
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• 2006

There is a principle of Korean Traditional Housing to be adapted for the nature using adaptable shapes to regional climate and easily available materials from the region then these environmentally friendly characteristics keep indoor environment from climate changes. These environmentally friendly characteristics to control indoor environment are very available for contemporary housing in that current issues, housing amenity and wellbeing, have basic goals same with what Korean Traditional Housing has. Therefore, this study begins to suggest fundamental data on indoor thermal environment control elements of Korean Traditional Housing to adapt those into contemporary housing through measurement of indoor thermal environment elements and evaluation on thermal sensation vote for Korean traditional housing. There was 24 hours measurement for indoor and outdoor thermal environmental elements to figure out competence to control indoor thermal environment of Korean Traditional Housing in summer. And subjective tests with 11 subjects was held in the morning, afternoon and night at intervals of 3${\sim}$4 hours to evaluate feeling and amenity for temperature and humidity of users.

• Journal of Sport and Applied Science
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• v.4 no.4
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• pp.1-6
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• 2020

Purpose: The purpose of this study is to identify the effect of 24-week sensory integration activity training on fitness of children with intellectual disability. Research design, data, and methodology: The subjects were 10 children with intellectual disability, 60 min training of sensory integration activity for 24 weeks. Obesity, cardiovascular endurance, muscular strength and muscle endurance were measured pre and post training. Frist, characteristics of subjects were measured with age, height, weight, IQ and SQ. Second, the subjects then performed sensory integration activity training for 24 weeks. Last, weight, strength, endurance, cardiovascular endurance and flexibility were measured. Data were calculated for average and standard deviation by SPSS 25.0 statistic program, and dependent sample t-test was processed to analyze the change between pre and post training. All statistical significance level was set to 0.5. Results: The result was shown that weight, strength and endurance changes between pre and post were significant. However, cardiovascular endurance, flexibility changes between pre and post were not significant. Conclusions: The lack of training frequency of 60 minute per week were acknowledged per week from this result. In future research, increased intensity and frequency are need for an in-depth and meaningful study and the measured data can be used basic information for the study.

• Journal of Korean Public Health Nursing
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• v.19 no.1
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• pp.18-29
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• 2005

The purpose of this study was to analyze the smoking behavior and to provide the basic data required to develop a smoking cessation program. The study subjects were 407 industrial workers in Jecheon. The data were collected using a structured questionnaire. The data were analyzed by the SPSS 10.0 system using descriptive statistics, t-test, and Chi-square test. The study results were as follows 1. Current smokers were $64.0\%$, ex-smokers were $19.1\%$. and non-smokers were $16.9\%$. 2. The most common motives of smoking were anger. anxiety, depression. and stress in the workplace. 3. In smoking habits, about $65.1\%$ of the current smokers smoked 11-20 cigarettes/day, and $91.0\%$ had smoked for more than 5 years. The smoking areas of the workplace were outdoor $37.9\%,\;rest\;room\;34.2\%,\; lobby\;23.0\%,\;corridor\;21.4\%,\;and\;office\;8.6\%$. 4. Regarding smoking cessation, $78.2\%$ of current smokers had attempted. The frequency of smoking cessation attempts was 1-3 or less in $67.2\%$ of smokers. The duration of smoking cessation was 1-3 month or less in $61.6\%$ of the smokers. 5. The mean score for smoking knowledge was 17.62, smoking attitude 75.74. and perceived health state 12.27. 6. There were significant differences between smokers and non-smokers 10 smoking attitude (t=5.29, p=0.00), and perceived health state(t=6.47, p=0.00). 7. As a result of the homogeneity test, both types of smoking and perceived health state proved to have significant differences in the change of health state compared with 4 weeks ago'$(x^2=20.26,\;p=0.00)$ and the level of satisfaction of health state in activities of daily living'$(x^2=15.47,\; p=0.05)$. The important findings of this study showed that a smoking cessation program needs to be developed to enhance the negative smoking attitude. to promote the perceived health state through smoking cessation, to encourage the intention of smoking cessation, and to develop strategies of stress management.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.378-383
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• 2005

This experimental study presents the results of the cooling performance test of a $CO_2$ heat pump system for fuel cell vehicles. The experimental facility provides the cool ing and heating environment for cabin and heat releasing component. The test loop is designed to target the cooling capacity of 5kW and its coefficient of performance (COP) of 2.2. The cooling performance of the heat pump system is strongly dependent on the refrigerant charge and the degree of superheat. We carried out basic experiments to obtain optimum refrigerant charge and the degree of superheat level at the internal heat exchanger outlet. The heat pump system for fuel cell vehicles is different from that of engine-driven vehicles, where the former has an electricity-driven compressor and the latter has the belt-driven (engine-driven) compressor. In the fuel cell vehicle, the compressor speed is an independent operating parameter and it is controlled to meet the cooling/heating loads. Experiments were carried out at cooling mode with respect to the compressor speed and the incoming outdoor air speed. The results obtained in this study can provide the fundamental cool ing performance data using the $CO_2$ heat pump system for fuel cell vehicles.