• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.4
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• pp.176-184
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• 2011

Cold air on sloping surfaces flows down to the valley bottom in mountainous terrain at calm and clear nights. Based on the assumption that the cold air flow may be the same as the water flow, current models estimate temperature drop by regarding the cold air accumulation at a given location as the water-like free drainage. At a closed catchment whose outlet is blocked by man-made obstacles such as banks and roads, however, the water-like free drainage assumption is no longer valid because the cold air accumulates from the bottom first. We developed an empirical model to estimate quantitatively the effect of cold pool on nocturnal temperature in a closed catchment. In our model, a closed catchment is treated like a "vessel", and a digital elevation model (DEM) was used to calculate the maximum capacity of the cold pool formed in a closed catchment. We introduce a topographical variable named "shape factor", which is the ratio of the cold air accumulation potential across the whole catchment area to the maximum capacity of the cold pool to describe the relative size of temperature drop at a wider range of catchment shapes. The shape factor is then used to simulate the density profile of cold pool formed in a given catchment based on a hypsometric equation. The cold lake module was incorporated with the existing model (i.e., Chung et al., 2006), generating a new model and predicting distribution of minimum temperature over closed catchments. We applied this model to Akyang valley (i.e., a typical closed catchment of 53 $km^2$ area) in the southern skirt of Mt. Jiri National Park where 12 automated weather stations (AWS) are operational. The performance of the model was evaluated based on the feasibility of delineating the temperature pattern accurately at cold pool forming at night. Overall, the model's ability of simulating the spatial pattern of lower temperature were improved especially at the valley bottom, showing a similar pattern of the estimated temperature with that of thermal images obtained across the valley at dawn (0520 to 0600 local standard time) of 17 May 2011. Error in temperature estimation, calculated with the root mean square error using the 10 low-lying AWSs, was substantially decreased from $1.30^{\circ}C$ with the existing model to $0.71^{\circ}C$ with the new model. These results suggest the feasibility of the new method in predicting the site-specific freeze and frost warning at a closed catchment.

• Journal of Yeungnam Medical Science
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• v.18 no.2
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• pp.215-225
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• 2001

Background: There are many evidences that inflammation is an important determinant of the development of atherosclerosis and one of the systemic markers of inflammation, C-reactive protein(CRP), is associated with extent of coronary artery disease and risk of coronary events. We assessed the time response of CRP response after coronary angioplasty and it's influence on the clinical restenosis in angina patients. Materials and Methods: Patients included 36 angina patients undergoing single vessel angioplasty. Levels of CRP were measured before and 12, 24, 48, and 72 hours after angioplasty. Clinical restenosis was assessed at 6 months after procedure. Results: Baseline CRP level was $0.30{\pm}0.01$ mg/dL in stable and $0.46{\pm}0.28$ mg/dL in unstable angina patients(p<0.05). After angioplasty, CRP level was increased with peak at 24 hour and persisted to 72 hours after angioplasty. At 24 hour after angioplasty, the magnitude of CRP change was $0.32{\pm}0.31$ mg/dL in stable and $0.79{\pm}0.73$ mg/dL in unstable angina patient(p<0.05). The change of CRP level was not associated with troponin-T after angioplasty. In unstable angina patients, clinical restenosis was developed in 8% of patients with low baseline CRP levels and in 50% of those with high baseline CRP levels more than 0.6 mg/dL(p<0.05). Conclusion: In unstable angina patients, inflammatory response is more increased than stable angina patients, and increased inflammatory response effects on the restenosis after coronary angioplasty.

• Journal of Chest Surgery
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• v.34 no.12
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• pp.901-908
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• 2001

Background : Coronary artery bypass graft(CABG) in patients with advanced left ventricular dysfunction has often been regarded as having high mortality rate, despite the great improvement in operative result of CABG. With recent advances in surgical technique and myocardial protection, surgical revascularization improved the symptom and long-term survival of these high risk patients more than the medical conservative treatment. Material and Methold : Clinical data of 31(4.1％) patients with preoperative ejection fraction less than 30% among 864 CABGs performed between January 1995 and March 1999 were retrospectively analyzed and pre- and postoperative changes of the ejection fraction on echocardiography were analyzed. There were 26 men and 5 women. The mean age was 60.7 years(range 41 to 72 years). History of myocardial infarction(30 cases, 98％) was the most common preoperative risk factor. There were seven irreversible myocardial infarction on thallium scan. Most patients had triple vessel diseases(26 cases, 84％) and first degree of Rentrop classification(16 cases, 52％) on coronary angiography. The mean number of distal anastomosis during CABG was per patient was 4.9${\pm}$0.8 sites in each patient. In addition to long saphenous veins, the internal mammary artery was used in 20 patients. Total bypass time was 244.7${\pm}$3.7 minutes(range, 117 to 567 minutes), and mean aortic cross-clamp time was 77.9 ${\pm}$ 1.6 minutes(range, 30 to 178 minutes). There were five other reparative procedures such as two left ventricular aneurysrmectomy, two mitral repair, and one aortic valve replacement. There were twelve postoperative complications such as three cardiac arrhythmia, two bleeding(re-operation), one delayed sternal closure, eleven usage of intra-aortic balloon counterpulsation for low cardiac output. Two patients died, postoperative mortality was 6.5% . Twenty-nine patients were relieved of chest pain and left ventricular ejection fraction after operation was significantly higher(38.5${\pm}$11.6%, p 0.001) as compared with preoperative left ventricular ejection fraction(25.3${\pm}$2.3%). The follow up period of out patient was 25. 3 months. Conclusion: In patients with coronary artery disease and advanced left ventricular dysfunction, coronary artery bypass grafting can be performed relatively safely with improvement in left ventricular function, but it will be necessary to study long term results.

• Korean Journal of Heritage: History & Science
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• v.55 no.4
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• pp.242-275
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• 2022

This study tries to reveal the structure of the "Kisun"(senior envoy ship) taken by senior envoys for the 10^th to 12^th visits to Japan from the perspective of professional shipbuilding engineering focusing on the theory of the ship in the travel logs of royal envoys to Japan (Sahaengrok) written by Joseon Tongsinsa that includes 12 visits to Japan for about 200 years from 1607 to 1811. The results of the study showed that the size of Kisun for the 10^th to 12^th envoy visits was 19 Pa (把) and a half in length and 6 Pa (把) and 2 Cheok (尺) in width. The height of the Sampan was found to be 2 Pa (把) and 1 Cheok (尺) based on records in Gyemisusarok and Jeungjeonggyorinji. The structure of Kisun was different for each visit but, it was found that Kisun was mainly composed of a main deck, bow (bow plate, stem plate), stern (stern plate), Sampan, Meonge (support), Garyong (support), Sinbang, Gungji, deck, two masts and sail, Gurejjak (mast support), Panok, stern Panok, Taru, dodger, anchor reel, stairs, rail, rudder, oar, and anchor. In addition, wood and iron nails were used together for connection. It was also found that the sail was made of herbage and cotton. This study found that Kisun, which was operated for the 10^th and 12^th envoy visits, was big in terms of length and height among the Joseon Tongsinsa fleet to show the authority and dignity of Joseon and that it had passages outside on the sides of the vessel and paddles were located between the sides and Panok structure and rails were installed on four sides on the Panok, improving stability and linear beauty. The walls of Panok were decorated with the royal Dancheong pattern and fancy murals. In addition, it was found that they wished for a safe voyage by drawing a demon face on the bow. Therefore, it was revealed that Kisun, which was taken by envoys as recorded in travel logs, was made by the state and equipped with structures and functions that enabled international voyages.

• Journal of Chest Surgery
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• v.36 no.10
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• pp.741-747
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• 2003

Background: Coronary artery bypass graf t (CABG) has been settled as most safe surgery among the open heart surgeries. However, in patients with cardiogenic shock, the emergency CABG has higher mortality than elective CABG. We analyzed thirty four patients who underwent emergency CABG and report the middle and long-term results. Material and Method: From June 1994 to December 2001, 34 patients who underwent emergency CABG at Kang-dong Sacred Heart Hospital were include in this study. On the basis of hospital databases and Out Patient Department (OPD) follow up data, preoperative diagnosis, risk factor, coronary artery anatomy, operation technique, postoperative mortality, complication, recurrence of symptom, and mid and long term mortality were analyzed retrospectively. Result: Indications for emergency CABG were 29 cardiogenic shocks (85.3%), 4 intractable chest pains (11.8%), and 1 polymorphic ventricular tachycardia (2.9%). Preoperative angiographic diagnoses were triple vessel disease in 16 (47.1%) and left main disease in 8 (23.5%) patients. We used saphenous vein grafts in 81 and left internal thoracic artery grafts in 14 anastomosis. The mean number of grafts per patients was 2.8$\pm$0.8. The mean aortic cross clamp time was 91.9$\pm$34.6 minutes and the mean cardiopulmonary bypass time was 262.7$\pm$198.3 minutes. Early mortality was 50% and the most common cause of early mortality was low cardiac output in 7 (20.6%) patients. The mean follow-up period was 30.9$\pm$35.7 months. There were no recurrences of symptom and late mortality. Conclusion: In the case of emergency operation, aggressive and proper management with drugs and IABP should be done for preoperative hemodynamic stability and early surgical intervention is the most important factor for patient salvage.

• Journal of Mushroom
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• v.12 no.3
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• pp.209-215
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• 2014

Changes in physical and chemical properties of oak sawdust were investigated by depth and time for 46 days during the fermentation process of 33 tons of the sawdust for oak mushroom cultivation. The degrees of change in the properties of the sawdust differed depending on the depth and fermentation period. Most of the physical-chemical properties except temperature and pH gradually changed during the fermentation. The temperature change was highly sensitive to the environment at the surface sawdust to 20 cm depth, while it gradually increased to the maximum $58.9^{\circ}C$ at 40~100 cm depths in 12 days and slowly to the maximum at 150 cm depth in 24 days. The moisture content of the sawdust decreased gradually from 31% to 26.5~28.0% in 24 days. Of the chemical properties during the fermentation, pH generally rose from 5.2 to 5.6, but it decreased to 4.4~4.7 at 150 cm depth in 16 days. While the carbon content of the sawdust was 68~70% without significant change, nitrogen content increased from 0.22% to 0.25% and thus C/N ratio gradually lowered from 320 to 280. P content in the sawdust gradually increased from 0.005% to 0.022% for 46 days. Osmotic concentration of the hot water extract of the sawdust varied 41.5~44.2 mmol/kg without significant change by the depth and time. The starch particles within initial ray parenchyma cells of sawdust decreased and fungal hyphae formed on the surface of the sawdust granules and within xylem vessel cells in 35 days. The effect of the sawdust fermentation on oak mushroom cultivation needs continued research.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.6
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• pp.659-665
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• 2008

This study is about zeolite synthesis from the sewage sludge incinerator fly ash of "S" sewage treatment center located in Seoul. For this purpose, the properties of raw fly ash as starting material, the hydrothermal conditions for zeolite synthesis and the environmental applicabilities of synthesized zeolites were examined. Fly ash from sewage sludge incinerator has large quantities of SiO$_2$ and Al$_2$O$_3$ and their contents are 42.8 wt.% and 21.2 wt.% respectively. So fly ash is considered to be possible starting material for zeolite synthesis. The results from leaching test of fly ash showed that the concentration of hazardous metals were very low as compared with the Korea leaching standard of the Waste Management Law. But the concentration from total recoverable test of fly ash were higher than the fertilizer standard of Fertilizer Management Law. Major zeolite products synthesized by hydrothermal reaction are analcime in teflon vessel and zeolite P1 in borosilicate flask. Optimum conditions for the synthesis of analcime were 1 N of NaOH concentration, 16 hour of reaction time and 135$^{\circ}C$ of reaction temperature. For the zeolite P1 formation, the proper conditions were demonstrated to be 5 N of NaOH concentration, 16 hour reaction time and 130$^{\circ}C$ of reaction temperature in this study. Hazardous metal contents in the analcime product are similar with those in raw fly ash. In case of the zeolite P1, the contents are reduced to nearly a half. Raw fly ash and the analcime product showed NH$_4{^+}$ ion exchange capacity of 0$\sim$1.0 mg of NH$_4{^+}$g$^{-1}$ and 3.0$\sim$7.4 mg of NH$_4{^+}$g$^{-1}$, respectively. However, the zeolite P1 product reached exchange capacity to 14.6$\sim$17.8 mg of NH$_4{^+}$g$^{-1}$. This values are in the range of those of natural clinoptilolite and phillipsite. From this point of view, zeolite synthesis from sewage treatment sludge incinerator fly ash is a good alternative for solid waste recycling.

• Journal of Chest Surgery
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• v.31 no.12
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• pp.1183-1194
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• 1998

Background: From Sept. 1985 to Sept. 1997, 2,000 cases of open heart surgery(OHS) were performed in the Department of Thoracic & Cardiovascular Surgery, Pusan Paik Hospital, College of Medicine, Inje University. Material and Method: Among the total of 2,000 cases of OHS, 1532 cases were congenital heart disease(CHD) and 468 cases were acquired heart disease(AHD). The age distribution was 9 days(4.0kg) to 68 years in CHD and 11 to 66 years in AHD. In 1532 cases of CHD, there were 1403 acyanotic cases and 129 cyanotic cases. Result: The CHD cases consisted of 940 ventricular septal defects(61.4%), 324 atrial septal defects(21.1%), 112 tetralogy of Fallot(7.3%), 46 pulmonary stenosis(3%), 38 endocardial cushion defects(2.5%), 15 valsalva sinus ruptures(1%), 4 transposition of great arteries (0.3%), 4 double outlet right ventricles(0.3%), and etc. Corrective operations were applied for congenital heart disease with a result of 3.1% hospital mortality. Of 468 AHD, 381 cases were valvular heart diseases, 48 ischemic heart diseases, 12 cardiac tumors, 8 annuloaortic ectasias, 16 dissecting aortic aneurysms and etc. In the 381 valvular heart diseases, there were 226 single valve replacements(36 aortic valve replacements(AVR), 188 mitral valve replacements(MVR), and 2 tricuspid valve replacements(TVR), among these were 71 cases of double valve replacements(AVR & MVR), 54 cases of MVR with tricuspid valve annuloplasty(TVA), and 18 cases of AVR, MVR with TVA. The total implanted prosthetic valves were 466. In MVR, 123 St. Jude Medical valves, 90 Carpentier-Edwards valves, 65 CarboMedics valves, 42 Sorin valves and 16 other valves were used. In AVR, 68 St. Jude Medical valves, 36 CarboMedics valves, 14 Carpentier-Edwards valves and 9 other valves were used. Coronary Artery Bypass Surgery(CABG) were performed in 48 cases. The patterns of bypass graft were 14 patients of single vessel graft, 21 patients of two vessels graft, 10 patients of three vessels graft and 3 patients of four vessels graft. Conclusion: The hospital operation mortality rate of congenital acyanotic, cyanotic and acquired heart diseases were 2.0%, 15.5%, and 5.1% respectively. The overall mortality rate was 3.6%(72/2,000).

• Journal of Chest Surgery
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• v.32 no.2
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• pp.108-118
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• 1999

Background: To evaluate the risk factor and long-term result of arterial switch operation , a retrospective study was done. Material and Method: A retrospective analysis was done to evaluate the early and long-term results on 58 patients who underwent an arterial switch operation(ASO) for transposition of the great arteries(TGA) with intact ventricular septum, between January 1988 and December 1996. Beforesurgery, 36 patients(62.1%) underwent balloon atrial septostomy, 32 patients(51.7%) received PGE1 infusion, and preparatory banding of pulmonary artery was performed on 6 patients(mean LV/RV pressure ratio 0.53$\pm$0.11). Result: The age at operation ranged from 1 to 137 days(mean 24$\pm$26 days) and the weights ranged from 1.8 to 6.8 kg (mean 3.5$\pm$0.8 kg). There were 14 early deaths(24.1%), but of the last 24 patients operated on since 1994, there were only 2 early deaths(8.3%). In the risk factor analysis, the date of operation was the only risk factor for early death(p-value < 0.01). Eight of the 14 early deaths were due to acute myocardial failure(mainly inadequate coronary blood flow). The length of follow-up ranged from 2 months to 8 years, average of 36$\pm$27 months. The follow-up included sequential noninvasive evaluations and 21 catheterizations and angiographic studies performed 5 to 32 months postoperatively with particular attention to the great vessel and coronary anastomosis, ventricular function, valvular competence, and cardiac rhythm. There were 5 late deaths(11.4%), one of thesedeaths was related to the late coronary problems, two to aspiration, one to uncontrolled chronic mediastinitis, and one to progressive aortic insufficiency and heart failure. The most frequent postoperative hemodynamic abnormality was supravalvular stenosis and the degree of pulmonary or aortic obstruction had slowly progressed in some cases, however there were no children who had to undergo a reoperation for supravalvular pulmonary or aortic stenosis. Aortic regurgitation was identified in 9 patients, which was mild in 7 and moderate in 2 and had progressed in some cases. Two patients who had an unremarkable perioperative course were identified as having coronary artery obstructions. The other late survivors were in good condition, were in sinus rhythm, and had normal LV functions. Actuarial survival rate at 8 years was 68.8%. Conclusion: We concluded that anatomic correction will be established as the optimal approach to the TGA with intact ventricular septum, though further long-term evaluations are needed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.1090-1094
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• 2008

Treatment effects of grape fruit stem extracts (GFSE) containing trans-resveratrol or fermented pollen (FP), and ethylene gas scavenging material (EGS) on the storage property of fresh jujube (Z izyphus jujuba forma hoonensis C.S. Yook) were investigated. Fresh jujubes were packed in different storage containers (PE film and Lock & Lock vessel), and treated with GFSE containing trans-resveratrol of 30 ppm or 1% FP, and EGS. The storage vessels were stored in refrigerator ($0{\pm}1^{\circ}C$) during 12 weeks, and then quality characteristics during storage period were analysed. Hardness slightly increased until 4 weeks and decreased afterward. Soluble solid ($^{\circ}Bx$) and total titratable acidity of fresh jujube slightly increased in all treatments during storage period. Vitamin C content of fresh jujube slightly decreased in all treatments during storage period. Number of microorganisms decreased until 4 weeks and increased afterward. The decay enzyme activity increased in all treatments during storage period. Storage stability was higher for PE film than Lock & Lock containers. Storage period of fresh jujube in this experiment ranges in $8{\sim}9$ weeks for maturity fruits treated with 30 ppm of GFSE and ethylene gas scavenging material.