• Tunnel and Underground Space
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• v.7 no.4
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• pp.293-298
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• 1997

Permeability was not represented as a simple function of the difference between confining pressure($P_c$) and pore pressure($P_p$). The effective pressure($P_e$) for measurements of the permeability is shown to be $P_c-{\alpha}P_p$, where $\alpha$ is a coefficient of effective pressure. Local values of $\alpha$ were determined at intervals along the pressure path which range 25MPa to 55MPa. The values of $\alpha$ ranged 0.65 to 1.09 for Pocheon granite and 1.20 to 1.43 for Wonju granite. Also, the value of $\alpha$ calculated by the cross-plotting method was 0.90 for Pocheon granite, 1.59 for Wonju granite and 4.35 for jointed Pocheon granite. $\alpha$ was found to be stress-history dependent.

• Journal of The Korean Dental Society of Anesthesiology
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• v.7 no.2
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• pp.126-130
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• 2007

Sedation is often indicated for the relief of anxiety for outpatient oral surgery. In combination with local anesthesia, it is safe and effective method of treatment. However, it is not always effective in allowing the physician to complete the planned oral surgery procedure. On occasion, a procedure is left unfinished due to patient combativeness and discomfort and hypertension in spite of increase in sedative doses. Episodic increases in blood pressure were most commonly caused by light anesthesia or sedation and by the patient's experience of pain during treatment. Female patient was 42 years old. blood pressure is 150/90 mmHg. Extraction and implant surgery was done under IV sedation. During seadtion, her blood pressure was increased (200/100 mmHg). Surgery was stopped. She was done monitoring blood pressure. The blood pressure was decreased to 130/90 mmHg. Sedation was failed due to significant hypertension. Blood pressure is seldom increased during sedation but we should evaluate the patient's medical history and know guideline for hypertension crisis.

• Journal of Ocean Engineering and Technology
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• v.21 no.1 s.74
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• pp.40-44
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• 2007

This paper presents the experimental results on slamming phenomenon. The air pressure cylinder was used to ensure repeatability of the impact. The results showed that the adopted experimental technique was excellent in terms of repeatability, compared to that of the free drop tests. The pressure time histories, magnitude of peak pressure and the behavior of jetspray were obtained. The flat specimen was tested for various incident angles. To estimate the incident speed of the specimen, a high-speed camera was used. The high-speed camera was also a useful tool in understanding the behavior.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.12
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• pp.1066-1072
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• 2000

This study is to investigate the pressure wave characteristics and the absorption of maximum and minimum pressure generated by instantaneous valve closure at the end of the straightening copper piping system with and without a water hammer arrester. Experiments were conducted under the following conditions : initial pressure 1~5 bar, flow velocity 0.6~3.0 m/s, water temperature $20^{\circ}C$ and air volume of water hammer arrester $80~180^cm^3$. Experimental results show that the optimum air volume of water hammer arrester is 110㎤.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.2
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• pp.234-240
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• 2012

The purpose of this case-control study is to investigate the relationship between storke and stroke risk factors, such as family history and past history. The case-control study over clinical data registered from Daejeon Oriental Medical Hospital in the period of November 2006 to July 2010. Study subjects consisted of 108 patients with acute stroke within 1 month as the case group (Cases) and 108 people who visited hospital for health care as the genreral control group (Controls). The participants had been interviewed by residents to find out their family history and past history. Their blood was taken to check the blood lipid level and liver function. 1. The people whose family history included cerebrovascular accident had more probability of stroke than the people who did not have cerebral vascular accident as their family history. 2. The people who suffered from hypertension had more probability of stroke than the people who did not suffer from hypertension. 3. The people who suffered from diabetes mellitus had more probability of stroke than the people who did not suffer from diabetes mellitus. Based on this study, the people who had cerebral vascular accident as their family history should thoroughly treat their blood pressure and blood sugar level to prevent the cerebral vascular accident.

• Proceedings of KHEA Conference
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• 1997.07a
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• pp.133-133
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• 1997

• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.3
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• pp.139-147
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• 2018

In the present study, effective hydrodynamic pressure modeling methods for three-dimensional earthquake safety analysis of a dam intake tower structure are investigated. Time history analysis results using the Westergaard added mass and Chopra added mass methods are compared with the one by the CASI (Coupled Acoustic Structural Interaction) method, which is accepted as giving almost exact solutions, to evaluate the difference in displacement response, stress and dynamic eccentricity. The 3D time history analysis of a realistic intake tower, which has the standard geometry widely used in Korea, shows that the Chopra added mass method gives similar results in displacement and stress and less conservative results in dynamic eccentricity to CASI ones, while the Westergaard added mass yields much more conservative results in all measures. This study suggests to use the CASI method directly for three-dimensional earthquake safety analysis of a dam intake tower, if computationally possible.

• Korean Journal of Health Education and Promotion
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• v.21 no.3
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• pp.117-131
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• 2004

Purpose: This study was conducted to evaluate the health behaviors and to find out risk factors of blood pressure of adult women in a rural area. Method: The convenient sample consisted of 159 adult women who lived in G-gun. The data was collected using a self-report questionnaire for health behaviors and mercury type sphygmomanometer for BP, between Jun I and August 15, 2003. Health behaviors measured smoking, alcohol, salt, lipid, stress, exercise, coffee, BMI and medication. To accomplish the goal of study, descriptive statistics, t-test, $x^2$-test, ANOVA and multiple regression analysis were. performed with SPSS 10.0. Results: The average age of subjects was 49.2(SD7.34)years old. The average SBP and DBP of subjects were 126.22mmHg(SDl6.73) and 8 1.25mmHg(SDl 0.31). There were significant differences in smoking(p=.000), cigarette consumption(p=.001), smoking duration(p=.000), BMI(p=.033), medication (p=.001), family history(p=.000) between normotensive and hypertensive. The main risk factors on SBP were medication, age, BMI, family history and smoking duration by 35.7% of the total variance these variables explained SBP. The main risk factors on DBP were BMI, education and medication by 17.60% of the total variance these variables explained DBP. Conclusion: These results suggest that health professional have to emphasize prevention of obesity, lasting medication and no smoking for prevention and management of hypertension in community health promotion program.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.10
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• pp.832-839
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• 2007

The geometry and dimensions of an expansion chamber are decisive factors in thermal puffer plasma chamber designs. Because they together dominate the temperature and speed at which the cooling gas from the chamber flows back through a flow channel to the arcing zone for the successful interruption of fault currents. In this study, we calculated the flow and mass transfer driven by arc plasma, and investigated the effects of a flow guide installed inside a thermal puffer plasma chamber. It is found that the existing cold gas of the chamber mixes with hot gases entrained from the arcing zone and is subjected to compression due to pressure build-up in the chamber. The pressure build-up with the flow guide is larger than that without due to a vortex which rotates clockwise around the chamber center. By the reverse pressure gradient, the mixing gas of the chamber flows back out for cooling down the residual plasma near current zero. In the case with the flow guide, the temperature just before current zero is lower than that without, and the Cu concentration with high electrical conductivity is also less than that without the flow guide.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.17 no.4
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• pp.213-220
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• 2005

An approach to calculate expected sliding distance of wave dissipating caisson breakwater is proposed. Time history of dynamic wave pressure for the calculation of sliding distance is made by extending conventional static wave pressure developed for the wave dissipating caisson breakwater. Construction of impact wave and standing wave was done by using duration time and maximum wave pressures of themselves. In the numerical analysis, the sliding distance for an attack of single wave and expected sliding distance for 50 years of wave dissipating breakwater by proposed method were compared with those by conventional method for uplift caisson breakwater. It was found that the sliding distance of wave dissipating breakwater by the proposed method is smaller than by conventional method.