• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.1
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• pp.1-11
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• 2022

The capacity of Jeju International Airport has reached its limit due to a surge in air traffic demand such as passengers and cargo and the continuous expansion of Low Cost Carriers (LCC). Despite COVID-19 that has began in November 2019, Jeju International Airport still has continuous demand in terms of passenger and cargo transportation. As a result, it is undeniable that the delay rate also unexpectedly increased as the air traffic volume at Jeju International Airport continued to increase. In this study, the correlation between Turnaround Time and delay rates of national airlines is analyzed based on past flight data at Jeju International Airport, and the cumulative delay time trend for sampled airlines is compared with Turnaround Time. Through this study, it is expected to contribute to securing aircraft operation efficiency and on-time by analyzing delays related to Turnaround Time at Jeju International Airport.

• Journal of Korean Society on Water Environment
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• v.38 no.2
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• pp.95-102
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• 2022

Studies for improving the efficiency of the traditional anaerobic digestion process are being actively conducted. To improve anaerobic digestion efficiency, this study tried to derive the optimal pretreatment conditions and mixing conditions by integrating the heat solubilization pretreatment of sewage sludge, livestock manure, and food waste. The soluble chemical oxygen demand (SCOD) increase rate of sewage sludge before and after heat solubilization pretreatment showed an increased rate of 224.7% compared to the control group at 170℃ and 25 min and showed the most stable increase rate. As a result of the biomethane potential test of sewage sludge before and after heat solubilization pretreatment, the total chemical oxygen demand (TCOD) and SCOD removal rates increased as the heat solubilization temperature increased, but did not increase further at temperatures above 170℃. In the case of methane generation, there was no significant change in the cumulative methane generation from 0.134 to 0.203 Sm³-CH₄/kg-COD at 170℃ for 15 min. As a result of the integrated digestion of organic waste, the experimental condition in which 25% of the sewage sludge, 50% of the food waste, and 25% of the livestock manure were mixed showed the highest methane production of 0.3015 m³-CH₄/kg-COD, confirming that it was the optimal mixing ratio condition. In addition, under experimental conditions mixed with all three substrates, M4 conditions mixed with 25% sewage sludge, 50% food waste, and 25% livestock manure showed the highest methane generation at 0.2692 Sm³-CH₄/kg-COD.

• Journal of Gastric Cancer
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• v.4 no.1
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• pp.1-6
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• 2004

Purpose: Despite numorous reports on the relationship between the level of carcinoembryonic antigen (CEA) in gall bladder bile and liver metastasis in colorectal cancer, no similar studies have been carried out for gastric carcinomas. We, therefore, undertook the present study to establish the relationship between the gall bladder bile CEA and liver metastasis as well as the post-operative survival rate in gastric carcinoma patients with curative resections. Materials and Methods: In 373 gastric cancer patients (252 males, 121 females, age $21\∼76$ years) operated on at Kosin University Hospital between 1989 1996, the CEA concentration in the gall bladder bile was determined during the operation and the value was related to the rates of post-operative survival and liver metastasis during follow-up period. Results: The overall rate of patient survival decreased gradually with increase in TNM stage. The 13-year postoperative survival rates for stages Ia, Ib, II, IIIa, and IIIb were $95.7\%,\;92.5\%,\;79.9\%,\;50.9\%,\;and\;43.3\$, respectively, and the 10-year survival rate for stage IV was $22.6\%$. The patients with a high ($\geq$10 ng/ml) biliary CEA showed a significantly lower rate of survival than those with a low (<10 ng/ml) biliary CEA. The 13-year cumulative survival rate was $55.4\%$ for the high CEA group and $76.5\%$ for the low CEA group (P<0.01). Also, the patients with a high biliary CEA showed a significantly higher rate ($11.5\%$) of liver metastasis than those with a low biliary CEA ($1.9\%$) (P<0.000). In patients with TNM stages (I and II), the CEA level did not affect the post-operative survival rates ($95.4\%\;and87.7\%$ in the high and low CEA groups, P>0.10), but in those with high TNM stages (III and IV), the survival rate was significantly lower in the high CEA group ($25.9\%$) than in the low CEA group ($57.8\%$) (P<0.05). Conclusion: These result suggest that the gall bladder bile CEA level obtained in an advanced-staged gastric cancer operation may be used in predicting the post-operational survival rate and in sorting out patients with a high risk for cancer recurrence, especially in the liver area.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.4
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• pp.717-722
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• 1992

An experiment was conducted to examine the feasibility of producing multiple calves using embryo transfer in Japanese Black cattle. Milk yield of cows and forage intake of calves were measured for 11 cows with single calves, 14 cows with twins and one cow with triplets. The means of 26 weeks cumulative milk yield were 854, 1028 and 1271 kg for cows having singles, twins and triplets, respectively. Male birth weights for single calves, twins and triplet were 34.9, 26.6 and 19.9 kg, and female ones were 31.7, 24.1 and 22.1 kg, respectively. Weight and daily gain of calves were affected by weeks (W), sex (S), the number of calves (N), parity, birth season, $W{\times}N$, $S{\times}N$ and regression on milk yield. Growth rate was higher for single calves than for twins until about 9 weeks of age, then weights increased at a similar rate. Male calf weaning weights for singles, twins and triplets were 207.0, 177.1 and 162.2 kg, and those for females were 185.4, 151.6 and 180.4 kg, respectively. Average regression coefficients of calf growth on milk yield were significant, and single calf was affected more than twin calves by increment of milk yield. As the number of calves per cow increased, hay intake of calves decreased and concentrate intake tended to increase between 6 and 13 weeks of age.

• Journal of Chest Surgery
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• v.20 no.1
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• pp.48-54
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• 1987

This report provides follow-up data on 557 patients [73 aortic, 357 mitral, and 127 multiple valve replacements] undergone lonescu-Shiley pericardial Xenograft valve replacement at Seoul National University Hospital between January, 1979 and December, 1985. There were 35 early death [6.3%] and 522 operative survivors were observed, and the cumulative follow-up is 1,140 patient-years [mean: 2.18 years per patient] The thromboembolic complications occurred in 34 cases [3.0% per patient-year] and the rate was 2.1% per patient-year for mitral and 0.3% per patient-year for aortic valve replacement in the presence of anticoagulation therapy. Among the 34 embolic episodes, 9 patients were dead [0.8% per patient-year] and the cause of death were 5 cerebral thromboembolism, 2 pulmonary embolism, and 2 intracerebral hemorrhage due to inappropriate anticoagulation after thromboembolic episode. Actuarial probability [+ SEM] of remaining free of thromboembolism for AVR is 88.1 x 11.1% at 5 years, for MVR 79.1 a 13.4% at 7 years and for multiple valve replacement 77.2 e 5.21% at 7 years. The incidence rate of thromboembolic complications after AVR is not less than that of MVR [0.3 Among the potential thromboembolic risk factors, atrial fibrillation is possible risk factor to increase the thromboembolic complication [0.05 < P < 0.1], but the importance of other factors, such as atrial clot, large left atrial size, mitral position, NYHA functional class, and age is less definite. A careful follow-up and the proper control of anticoagulation without omission, poor control, and arbitrary withdrawal is important for the successful management of the thromboembolic complications and the anticoagulation-related morbidity and mortality.

• Korean Journal of Materials Research
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• v.5 no.1
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• pp.12-21
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• 1995

The study was performed to study the effects of strain rate on acoustics emission( AE) during bulging test in corrosive environmentsynthetic sea water. The strain rates used were in the range $4 \times 10^{-6}S^{-1}$ to $1 \times 10^{-4} \times S^{-1}$ and the parameters used to evaluate AE signal characteristics were AE hit and amplitude. It can be observed that the cumulative AE hit and average amplitude during fracture process increase highly at decreasing strain rates while the equivalent fracture strain and the crack length of circumferencial direction become decrease. The peak point of AE signal characteristic parameters approach to the first half of test. When the average amplitude per unit equivalent fracture strain was above 20dB, it was definitly observed stress corrosion cracking phenomena. Additional, we knew that the AE test had the possibility to evaluate SCC susceptibility with various strain rates.

• Korean Journal of Clinical Pharmacy
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• v.28 no.3
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• pp.194-203
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• 2018

Background: Bone fractures are high in elderly patients with type 2 diabetes mellitus (T2DM). Hyperglycemia and chronic kidney disease may increase the risk of fracture prevalence via altered bone metabolism, but whether glycemic control and kidney function are associated with the risk of fracture prevalence remains unclear. This study evaluated the relationship between glycemic control and baseline estimated glomerular filtration rate (eGFR) and risk of fracture prevalence in older and middle-aged patients with T2DM. Methods: Patients who underwent a general medical check-up between 2009 and 2013 were selected from the Korean National Health Insurance Sharing Service records. Chi-square test and multiple logistic regression analysis were used to assess the relationship between glycemic control and eGFR and risk of fracture prevalence. Results: Cumulative fracture prevalence were higher in patients with T2DM, irrespective of whether they had tight or less stringent glycemic control (fasting blood glucose [FBG] ${\geq}110mg/dL$). After adjustment for baseline age and FBG, tight and less stringent glycemic control was significantly associated with increased adjusted risk of fracture prevalence in middle-aged patients with T2DM (OR=1.13, 95% CI, 1.05-1.21, p=0.0005 vs OR=1.13, 95% CI, 1.06-1.20, p=0.0001), but not in older patients. Baseline eGFR was not significantly related to fracture prevalence in either older or middle-aged patients. Conclusion: Less stringent glycemic control significantly increased the adjusted risk of fracture prevalence in middle-aged patients with T2DM. Further studies are needed to confirm the effect of tight glycemic control on fracture prevalence.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.6181-6184
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• 2013

Background: Lung cancer is the most frequent cancer in males and the fourth most frequent site in females, worldwide. This study is the first to explore the profile of lung cancer in Kuwait. Materials and Methods: Cases of primary lung cancer (Kuwaiti) in Kuwait cancer Registry (KCR) were grouped in 4 periods (10 years each) from 1970-2009. Epidemiological measures; age standardized incidence rate (ASIR) with 95% confidence intervals (CI), Standardized rate ratio (SRR) and Cumulative risk and Forecasting to year 2020-2029 used for analysis. Results: Between years, 2000-2009 lung cancer ranked the 4th and the 9th most frequent cancer in males and females respectively. M:F ratio 1:3. Mean age at diagnosis (95%CI) was 65.2 (63.9-66.4) years. The estimated risk of developing lung cancer before the age of 75 years in males is 1.8% (1/56), and 0.6 (1/167) in females. The ASIR for male cases was 11.7, 17.1, 17.0, 14.0 cases/100,000 population in the seventies, eighties, nineties and in 2000-2009 respectively. Female ASIR was 2.3, 8.4, 5.1, 4.4 cases/100,000 population in the same duration. Lung cancer is the leading cause cancer death in males 168 (14.2%) and the fifth cause of death due to cancer in females accounting for 6.1% of all cancer deaths. The ASMR (95%CI) was 8.1 (6.6-10.0) deaths/100,000 population and 2.8 (1.3-4.3) deaths/100,000 population in males and females respectively. The estimated Mortality to incidence Ratio was 0.6. Conclusions: The incidence of lung cancer between years 2000-2009 is not different from that reported in the seventies. KCR is expecting the number of lung cancer cases to increase.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.6
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• pp.380-386
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• 2007

Egg development and juvenile growth of the Pacific cod Gadus macrocephalus (Korean East Sea Population) were studied to increase fry production using mass cultivation. The eggs were rectangular and adhesive sinking type. The egg size and fertilization rate were 1.01-1.09 mm and 72.4%, respectively. The cumulative times for egg hatching at 3, 6, 9, and $12\;^{\circ}C$ were 600, 360, 240, and 192 hrs, respectively. The hatching rates at 3, 6, 9, and $12\;^{\circ}C$ were 60.2, 68.9, 62.5, and 40.6%, respectively. After 11, 45, and 90 days, the larvae grew to a total length of 5.46-5.99, 9.42-10.06, and 23.0-32.0 mm, respectively. At 100 days from hatching, they grew to an average of 30 mm with a 7.1 % survival rate. By 312 days, juveniles with a total length of 3.6 cm grew to a total length of 14.7-20.1 cm and a body weight of 38.4-73.9 g. The specific growth rates of total length and body weight of the juveniles were 0.50% and 1.12%, respectively.

• Tuberculosis and Respiratory Diseases
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• v.68 no.6
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• pp.345-349
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• 2010

Background: The polymerase chain reaction (PCR) test is important for the confirmatory diagnosis of tuberculosis (TB) caused by Mycobacterium tuberculosis. The aim of this study was to analyze the yield of repeated PCR testing in patients with confirmed pulmonary TB. Methods: The medical records of 130 patients, who had more than two consecutive PCR tests and a M. tuberculosis-positive sputum culture from August, 2006 to December, 2007, were retrospectively reviewed for the purposes of this study. A positive TB-PCR test was defined as at least one positive test result. Results: The cumulative positive PCR test rate was 80% (104/130), with gradually increasing rates of positive findings upon the first, second and third TB-PCR tests with 52.3%, 68.5% and 75.4%, respectively. However, further testing did not increase the positive rate further. Conclusion: Repeated PCR testing at least three times for M. tuberculosis is helpful for diagnosis of pulmonary TB.