• Journal of Korean Association for Spatial Structures
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• v.20 no.1
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• pp.49-59
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• 2020

This study investigates the wind pressure characteristics of elliptical plan retractable dome roof. Wind tunnel experiments were performed on spherical dome roofs with varying wall height-span ratios (0.1~0.5) and opening ratios (0%, 10%, 30% and 50%), similar to previous studies of cirular dome roofs. In previous study, wind pressure coefficients for open dome roofs have been proposed since there are no wind load criteria for open roofs. However, in the case of Eeliptical plan retractable dome roof, the wind pressure coefficient may be largely different due to the presence of the longitudinal direction and transverse direction. The analysis results leads to the exceeding of maximum and minimum wind pressure coefficients KBC2016 code.

• New & Renewable Energy
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• v.10 no.4
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• pp.9-15
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• 2014

In this study pressure and shaft torque pulsation were measured with variation of head and flow during the model test for a 15 MW Francis Turbine. Pressure pulsations were measured at the inlet of the spiral casing and 4 points in the cone of the diffuser and shaft torque pulsation at the upper position of the turbine. The maximum amplitude of pressure pulsation appeared 2.03% of the maximum rated head with the frequency of 25% of the rated revolution and at the guide vane opening of $10^{\circ}$. Shaft torque pulsation appeared 0.01% of the rated shaft torque, fairly low value. Air was admitted through the cone and pressure pulsation gradually decreased with increase of air flow and kept nearly constant after 5% of the rated flow. A new Francis turbine of which specific speed is 115 m-kW had been designed to rehabilitate the old one and the model test was performed at EPFL. The commercial code, STAR-$CCM^+$ was used for numerical simulation of flow.

• Women's Health Nursing
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• v.14 no.1
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• pp.28-35
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• 2008

Purpose: The study was performed to evaluate effects of aroma therapy on the anxiety, blood pressure and pulse of uterine leiomyoma patients before surgery and to apply it as the actual nursing intervention. Method: From Aug1st to Nov. 30th, 2007, the experimental group (n=30) and the control group (n=30) were selected in 1 hospital, Busan. Lavender and Bergamot oil mixed together at a 3:2 ratio was applied to the experimental group two times at 8-9 pm the day before surgery and twice 30 minutes before the surgery. Anxiety, VAS, blood pressure, and pulse were measured to evaluate the effects of aroma therapy. The data analysis was done using the SPSS/PC 12.0 program using chi-square test and t-test. Results: Hypothesis 1 was supported. The VAS of the experimental group was lower than control group after aroma therapy. Hypothesis 2 was partly supported. The systolic blood pressure and pulse of experimental group was significantly decreased, but diastolic blood pressure wasn't difference. The VAS, systolic blood pressure and pulse of control group were increased. Conclusion: The study verified that the aroma therapy is a very effective nursing intervention that can reduce anxiety before surgery. It is recommended to apply aroma therapy actively to patients experiencing anxiety before surgery procedure.

• Journal of The Korean Society of Integrative Medicine
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• v.6 no.2
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• pp.107-115
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• 2018

Purpose : The purpose of this study was to determine the effects of the McKenzie cervical exercise program on cervical pressure pain and balance in industrial workers. Method : The subjects, who consisted of 26 industrial workers, were randomly divided into two groups. The control group (n=13) went about their daily living routines. The other group (n=13) used the McKenzie cervical exercise program for 6 weeks (2 to 3 times/day). Pressure threshold and balance ability tests were completed before and after the experiment. The balance test was performed both with the eyes open and closed in a standing position. Result : There were significant improvements in the pressure threshold and balance ability test for the McKenzie cervical exercise program group (p<.05), while the control group showed no significant changes (p>.05). Conclusion : The above results revealed that the McKenzie cervical exercise program is effective in improving balance and cervical pressure pain.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.10a
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• pp.546-552
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• 2012

This paper is a study on squeal noise simulation under the consideration of temperature and pressure dependent material properties of friction material. For this, data of pressure and temperature dependent material properties of lining is achieved by using lining data base and exponential curve fit. Complex eigenvalue analysis is performed for predicting squeal noise frequency and instability and chassis dynamo test is performed for achieving squeal noise frequency, sound pressure level, occurrence temperature & pressure. Initial multi models are composed for considering complex interface conditions such as pad ear-clip, piston-housing and guide pin-torque member. The simulation result of base models is compared with the test result. Squeal noise simulation under the consideration of temperature and pressure dependent material properties of friction material is performed and analyzed using multi models. And additional condition is disc material property variation. Entire simulation conditions are combined and analyzed. Finally, this paper proposes direction of the warm squeal noise model.

• 기술발표회
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• s.2006
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• pp.162-171
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• 2006

Segmental Grid Retaining Wall is one of the segmental grid retaining walls using headers and stretchers to establish the framework of the wall In this method, grids formed by the intersection of headers and stretchers are generally filled with the gravel to maintain the weight of the wall Therefore, the construction can be carried out with higher speed and much economically when compared with the concrete retaining wall Furthermore, it has high drain capacity, and environmentally friendly aspects also have been pointed out because the possibility of the planting at the front of the wall However, in the segmental grid retaining wall method, the relative movement between the individual headers and stretchers was generally recognized, and stress redistribution in the gravel filling was also observed when subjected to the external loading and self-weight of filling Therefore, it has been thought that the distribution of the earth pressure in the segmental grid retaining wall system differ from that of the concrete retaining wall In this study, the surcharge tests using the scaled model segmental grid retaining wall was carried out to observe the distribution of the earth pressure in the segmental grid retaining wall The earth pressure was measured in the six specified height of wall, and the distribution of the pressure was analyzed. Furthermore, the earth pressure by computation or by the test using the concrete retaining wall was also considered to make comparison

• Corrosion Science and Technology
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• v.3 no.6
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• pp.233-239
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• 2004

Primary water stress corrosion cracking of steam generator tubings occur on many tubes in pressurized water reactors(PWRs), and they are repaired using sleeves or plugs. In order to develop proper repair criteria, it is necessary to know the leak behavior of the tubes, which have stress corrosion cracks. Crack development tests were carried out on the tubes at room temperature, and leak rate and burst pressure were measured on the degraded tubes at room temperature and a high temperature. No leakage was detected on the tubes where 100 % through wall crack developed, at 1560 psi, which is an operating pressure difference of pressurized water reactors(PWRs). In some tests, leak rates of the tubes increased with time at a constant internal water pressure. A test tube showed a very small amount of leakage at 2700 psi in a high temperature pressure test at $282^{\circ}C$, but it disappeared after the pressure increased slightly. Even cracks are 100 % through wall, they need to open in order to reach a certain amount of leak rate at the operating pressure difference.

• Journal of Korean Biological Nursing Science
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• v.10 no.1
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• pp.62-68
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• 2008

Purpose: This study was conducted to test the effect of the 12 weeks brisk walking exercise program on body composition, blood pressure, blood glucose and blood lipid for middle-aged woman with obesity. Method: The subject were 25 obese women in 40-64 yr old who were composed of over 30% body fat. For the analysis, descriptive statistics, paired t-test were used for statical analysis with SPSS 15.0. Result: The results were summarized as follows: first, the body weight, body mass index (BMI), % body fat of the obese woman were significantly decreased after implementing the 12 weeks brisk walking exercise program (p<.5). Second, the systolic blood pressure, diastolic blood pressure and blood glucose were significantly decreased after the 12 weeks brisk walking exercise program (p<.5). Third, the serum cholesterol was significantly decreased (p<.05) but serum triglyceride was not significantly decreased the after 12 weeks brisk walking exercise program. Conclusion: These results suggest that the brisk walking exercise program has an effect on decreasing body weight, BMI, percent body fat, blood pressure and serum cholesterol in middle-aged woman with obesity to reduce obesity and prevent chronic disease.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.5
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• pp.658-668
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• 1999

The objective of the present study is to investigate the effect of experimental parameters on the hydrodynamic characteristics in a horizontal tee-type evaporator using R-22. The experimental apparatus consisted of an unheated tee-type test section, a liquid-vapor separator, a preheated, mass flow meters, a plate heat exchanger, pump, and other measurement devices. The experimental parameters were mass flux(500 and 600kg/$m^2$s), inlet quality(0.1~0.3) and separation ratio(0.3~0.7). Absolute pressure at the inlet of the test section was 0.652 MPa. The branch-to-inlet inner diameter ratio was 0.61. Pressure gradient at the branch section was larger than that at the run section at the same separation ratio. Pressure drop per unit length increased at the run section and decreased at the branch section as the separation ratio increased. Pressure drop predicted by the separated flow model agreed with experimental data within -35 to +16%. Generally, predicted values showed similar trend with the data. Mass flow ratio of vapor refrigerant was affected by the inlet quality more than the mass flux.

• Journal of East-West Nursing Research
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• v.16 no.1
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• pp.11-18
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• 2010

Purpose: The aim of this study was to examine the characteristics of hypertension-related nursing intervention programs and their effects on systolic and diastolic blood pressure. Methods: Fifteen studies were selected from four databases (Korean studies, Riss4U, RICHIS, and JKAN) published as of 2009. They were analyzed by meta-analysis method. The selected studies contained a control group with pre-test and post-test design, measured blood pressure as a dependent variable, and used a reported statistical value for blood pressure to measure the size of effects. Results: The hypertension-related nursing intervention programs were relatively effective in lowering both systolic and diastolic blood pressure, although they were more efficient to decrease diastolic pressure. Among the hypertension-related intervention programs, complementary and alternative therapies were more effective in lowering blood pressure compared to lifestyle change intervention. Conclusions: To acquire substantial data of intervention effects, and complementary and alternative therapy, subjects in pre-hypertensive stage, and elderly people, better industrial and scholastic research methods need to be developed for future research. Further studies are needed to establish complementary and alternative therapies. Studies with different group of participants and studies using effective research design are in need as well.