• Journal of the Microelectronics and Packaging Society
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• v.9 no.1
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• pp.49-52
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• 2002

This study demonstrated the feasibility of tape casting method to fabricate soda borosilicate glass-coated stainless steel electrostatic chucks(ESC) for low temperature semiconductor processes. Glass coating on the stainless steel substrate was 125 $\mu\textrm{m}$ thick. The adhesion of glass coating was found to be excellent such that it was able to withstand temperature cycling to over $300^{\circ}C$ without cracking and delamination. The electrostatic clamping pressure generally followed the theoretical voltage-squared curve except at elevated temperatures and high applied voltages. The deviations at elevated temperatures and high applied voltages are due to increased leakage current as the electrical resistivity of glass coating drops.

• Proceedings of the KSME Conference
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• 2000.11b
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• pp.67-76
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• 2000

Cr-Mo low alloy steels have been used for a long time for pressure vessel due to its excellent corrosion resistance, high temperature strength and toughness. The paper reviewed the latest trends on material development and some problems on Cr-Mo low alloy steel for pressure vessel, such as elevated temperature strength, hardenability, synergetic effect between temper and hydrogen embrittlement, hydrogen attack and hydrogen induced disbonding of overlay weld-cladding.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.67-76
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• 2000

Cr-Mo low alloy steels have been used for a long time for pressure vessel due to its excellent corrosion resistance, high temperature strength and toughness. The paper reviewed the latest trends on material development and some problems on Cr-Mo low alloy steel for pressure vessel, such as elevated temperature strength, hardenability, synergetic effect between temper and hydrogen embrittlement, hydrogen attack and hydrogen induced disbonding of overlay weld-cladding.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.12 no.1
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• pp.126-133
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• 2016

Recently, the research and development of Sodium-cooled Fast Reactors (SFRs) have made progresses. However, liquid sodium, the coolant of an SFR, is chemically unstable and sodium fire can be occurred when liquid sodium leaks from sodium pipe. To reduce the damage by the sodium fire, many fire walls and fire extinguishers are needed for SFRs. LBB concept in SFR might reduce the scale of sodium fire and decrease or eliminate fire walls and fire extinguishers. Therefore, LBB concept can contribute to improve economic efficiency and to strengthen defense-in depth safety. The LBB assessment procedure has been well established, and has been used significantly in light water reactors (LWRs). However, an LBB assessment of an SFR is more complicated because SFRs are operated in elevated temperature regions. In such a region, because creep damage may occur in a material, thereby growing defects, an LBB assessment of an SFR should consider elevated temperature effects. The procedure and method for this purpose are provided in RCC-MRx A16, which is a French code. In this study, LBB assessment was performed for PGSFR IHTS hot-leg pipe according to RCC-MRx A16 and the applicability of the code was discussed.

• Korean Journal of Community Nutrition
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• v.5 no.2
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• pp.161-171
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• 2000

The purpose of this study was to investigate the effects of smoking and/or alcohol drinking on the nutrient intake, nutritional status, and eating habits of adult males. The subjects were 157 male adults aged 20-49 living in Daejon. Interviews with questionaire on smoking and alcohol drinking habits and eating habits, anthropometric measurement, biochemical blood test, and dietary assessment by one-day 24 hour recall and two-day diet record were carried out. The subjects were divided into four groups : control (non-smoking and non-drinking), drinking only, smoking only, and the both(drinking and smoking). The average numbers of smoked cigarettes were 17.8/d and 19.1/d in the smoking only group and the both group, respectively. The frequency of alcohol drinking was 8.3 times/month and 11.6 times/month in the drinking only group and the both group, respectively. Height was significantly higher(P 0.05) in the drinking only group than in the none and smoking only groups, while the other anthropometric indices were not different among the four groups. There were positive correlations between smoking and drinking or coffee intake. Alcohol drinking increased eating-out frequency and the intakes of energy, protein, dietary fiber, vitamin A, B$_1$,$ B_6,$ Fe and P, while smoking decreased snack frequency and intakes of energy, protein and vitamin $ B_6,$. Blood pressure was not changed in the smoking only and drinking only groups compared to the none group, while systolic blood pressure was elevated in both group(P 0.05). Alcohol drinking significantly elevated(P 0.05) serum total cholesterol and LDL-cholestrol level, while smoking did not change the serum lipid and cholesterol levels. Hemoglobin nd MCHC levels were significantly elevated(P 0.05) by smoking. From these data, it is suggested that both smoking and drinking have influence on some eating habits and nutrient intakes, and especially alcohol drinking can induce hypercholesterolemia.

• Geomechanics and Engineering
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• v.12 no.4
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• pp.707-721
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• 2017

The objective of this paper is to experimentally study the consolidation of saturated silty clay subjected to repeated heating-cooling cycles using a modified temperature-controlled triaxial apparatus. Focus is placed on the influence of the water content, confining pressure, and magnitudes and number of thermal loading cycles. The experimental results show that the thermally induced pore pressure increases with increasing water content and magnitude of thermal loading in undrained conditions. After isothermal consolidation at an elevated temperature, the pore pressure continues to decrease and gradually falls below zero during undrained cooling, and the maximum negative pore pressure increases as the water content decreases or the magnitude of thermal loading increases. During isothermal consolidation at ambient temperature after one heating-cooling cycle, the pore pressure begins to rise due to water absorption and finally stabilizes at approximately zero. As the number of thermal loading cycles increases, the thermally induced pore pressure shows a degrading trend, which seems to be more apparent under a higher confining pressure. Overall, the specimens tested show an obvious volume reduction at the completion of a series of heating-cooling cycles, indicating a notable irreversible thermal consolidation deformation.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.4
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• pp.555-560
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• 2000

This paper describes the macroscopic behavior and atomization characteristics of the high-pressure gasoline injector in direct-injection gasoline engine. The global spray behavior of fuel injector was visualized by shadowgraph technique. The atomization characteristics of gasoline spray such as mean diameter and mean velocity of droplet were measured by the phase Doppler particle analyzer system. In order to obtain the influence of fuel injection pressure, the macroscopic visualization and experiment of particle measurement on the fuel spray were investigated at 3,5 and 7 MPa of injection pressure under different surrounding pressure in the spray chamber. The results of this work show that the fuel injection pressure of gasoline injector in GDl engine has influence upon the mean droplet diameter, mean velocity of spray droplet, the spray tip penetration, and spray width under the elevated ambient pressure.

• Archives of Plastic Surgery
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• v.44 no.4
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• pp.276-282
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• 2017

Perioperative hypertension is a phenomenon in which a surgical patient's blood pressure temporarily increases throughout the preoperative and postoperative periods and remains high until the patient's condition stabilizes. This phenomenon requires immediate treatment not only because it is observed in a majority of patients who are not diagnosed with high blood pressure, but also because occurs in patients with underlying essential hypertension who show a sharp increase in their blood pressure. The most common complication following facelift surgery is hematoma, and the most critical risk factor that causes hematoma is elevated systolic blood pressure. In general, a systolic blood pressure goal of <150 mm Hg and a diastolic blood pressure goal of >65 mm Hg are recommended. This article discusses the causes of increased blood pressure and the treatment methods for perioperative hypertension during the preoperative, intraoperative, and postoperative periods, in order to find ways to maintain normal blood pressure in patients during surgery. Further, in this paper, we review the causes of perioperative hypertension, such as anxiety, epinephrine, pain, and postoperative nausea and vomiting. The treatment methods for perioperative hypertension are analyzed according to the following 3 operative periods, with a review of the characteristics and interactions of each drug: preoperative antihypertensive medicine (atenolol, clonidine, and nifedipine), intraoperative intravenous (IV) hypnotics (propofol, midazolam, ketamine, and dexmedetomidine), and postoperative antiemetic medicine (metoclopramide and ondansetron). This article focuses on the knowledge necessary to safely apply local anesthesia with IV hypnotics during facelift surgery without the assistance of an anesthesiologist.

• Journal of Korean Academy of Nursing
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• v.24 no.3
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• pp.377-388
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• 1994

The purpose of this study was to determine the effects of music therapy on changes in the vital signs of patients about to undergo an operation. The patients listened to the music at a time when they were feeling preoperative anxiety up until the preanesthesia was given in the operating room. The subjects for this study were selected from sixty patients to undergo operations, who were hospitalized at Dong Eui hospital in Pusan city. They were assigned to two groups, thirty to the experimental group and thirty to the control group. The subjects were from 20 years old to 69 years old, and had no other problem except the one requiring the operation, and no premedication. The data were collected during the period from July 1 to September 30, 1993. The method used in this study was to measure state-anxiety on the ward in the morning of the operation, and vital signs immediately before leaving for the operating room. Vital signs were measured immediately before the anesthesia was given and after the experimental group had listened to the music during the ten minutes needed to prepare the operation setting. The control group just waited during ten mimutes. Vital signs were check again before the anesthesia was given. The data were analyzed by descriptive statistics, mean±SD, p-value, and t-test using the SPSS progrom. The results of this study are : 1. Systolic blood pressure taken in the operating room was elevated, over the level measured on the ward, by 5.00 ± 15.26㎜Hg in experimental group and 18.67±14.56㎜Hg in control group. (t=-3.5496, p=.0008) 2. Diastolic blood pressure was elevated by 6.67±12.95㎜Hg in experimental group and 18.67±12. 79㎜Hg in control group. (t=-3.6100, p=.0006) 3. Pulse was elevated by 2.931±9.44 / min in experimental group and 8.03±8.37 /min in control group. (t=-2.2144, p=.0307) 4. Respiration was elevated by 0.60±1.35 /min in experimental group and 1.57±1.48 /min in control group. (t=-2.6409, p=.0106) 5. Body temperature was down by 0.13±1.91'c in experimental group and elevated by 1.13±1.11'c in control group. (t=-3.1471, p=.0026) Thus, in this study there was a statistically significant difference in the change in the vital signs between the experimental group treated with music therapy and the control group which received no treatment. Because music therapy is valuable to decrease the anxiety of patients facing operations, the result of this study support its effect in relieving anxiety as a valuable nursing intervention. From this study, the following recommendations can be made : First, it is necessary to further study music therapy to develope a better system and determine optimal time. Second, it is necessary that more detailed re-search on measurement of changes in vital signs be done to determine changes over time intervals.

• Korean Journal of Community Nutrition
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• v.1 no.2
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• pp.178-188
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• 1996

Blood pressure distribution of adolescents and its several related factors including obesity were investigated through blood pressure measuring by automated oscillometric method, anthropometry, and questionnaire. Subjects were 480 female and 480 male middle school students living in Taejon. Mean values of systolic(SBP)/diastolic(DNP) blood pressure of male and female students were 118.4$\pm$11.0/69.5$\pm$9.6 mmHg and 116.9$\pm$10.4/69.5$\pm$8.6 mmHg, respectively. Their blood pressures, particularly SBP, increased with age and showed higher value in the males than in the females. All frequency distributions of SBP and DBP, by sex and age, showed normal curves and their 50th, 90th, and 95th percentiles were presented. As obese index increased, both SBP and DBP were elevated and the prevalence of hypertension which was classified by Task Force Report(1987) increased, particularly in male students. Body weight and BMI were positively correlated with both SBP and DBP, and hight was also positively correlated with SBP or DBP. Our data inicated that blood pressure and hypertension prevalence of adolescents tended to increase and various internal and external environmental factors affected them. It was emphasized that blood pressure measurement should be done in every medical examination of adolescents and the nationwide Korean standard of blood pressure for adolescents have to be prepared. (Korean J Community Nutrition 1(2) : 178-188, 1996)