• Journal of Power System Engineering
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• v.12 no.3
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• pp.55-59
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• 2008

In this paper, we have investigated on collection efficiency of fine particle of glass fiber-filter bag according to the surface treatment. The solution consisted of polytetrafluoroethylene(teflon), graphite powder, silicon resin and water was used as a basic surface treatment agent. Tensile strength of glass filter-bag increased with up to 3hrs and then decreased with surface treatment time. Tensile strength and initial modulus of the glass fiber-filter bag treated by iodine after basic surface treatment for 3hrs were lower than those of basic surface treatment for 3hrs, however collection efficiency and fracture strain were higher than those of basic surface treatment for 3hrs. Glass fiber-filter bag with lower initial modulus and more strain will be extend the durable period and the one treated by iodine after basic surface treatment 3or 3hrs is expected high collection efficiency of fine particle. This method makes it possible to manufacture glass fiber-filter bag of the optimum condition.

• Journal of Chest Surgery
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• v.15 no.3
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• pp.346-354
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• 1982

A Complete transposition of the great arteries combined with V.S.D, A.S.D, dextrocardia, and P.S is a rare congenital anomaly. The patient was a 10 year-old female whose complaints were frequent URI, exertional dyspnea, and cyanosis at rest since birth. Cheat X-ray films showed Dextrocardia ; situs inversus, moderate cardiomegaly, and Characteristic egg-shape heart shadow. E.K.G, Echocardiography, Cardiac Catheterization, and Angio-Cardiography were performed. Open heart Surgery was done under diagnosis of d-TGA, Dextrocardia, V.S.D, A.S.D, and P.S. At the time of Operation, Dextroeardia, T.G.A, Secndum type A.S.D, A.S.D, and P.S. At the time of Operation, Dextroeardia, T.G.A, Secndum type A.S.D. ($2.0{\times}2.0cm$. in diameter), V.S.D. type II ($1.5cm{\times}1.5cm$ in diameter), and pulmonary valvular stenosis were noted. Mustard operation using pericardial Baffle in the atrium for T.G.A. was perforsned. Teflon patch graft for closure of V.S.D. through tricuspid orifice and pulmonary Valvulotomy through pulmonary arteriotomy were performed. The post-op, low cardiac output Syndrome and dysrhythmicawere developed till Postoperative day #7, so that was controlled by inotropic and antiarrhythmic agents. After that, patient's conditions were Uneventful.

• Journal of Chest Surgery
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• v.12 no.4
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• pp.339-345
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• 1979

Mitral valve disease is the most common disease of the acquired heart diseases, and atrial septal defect is also one of common congenital heart diseases. Coexistence of these two lesions is rare, but of great hemodynamic interest. Among 443 cases with mitral valve disease and 90 cases with atrial septal defect experienced in the Department of Thoracic Surgery, Seoul National University Hospital, there were 6 cases with atrial septal defect complicated by mitral valve disease. 1. Of the 6 patients, four were female and two were male. The age was ranged from 18 to 46. 2. Atrial septal defect was ostium secundum type in all cases, and the mitral valvular lesions were regurgitation in four and stenosis in two. Type II ventricular septal defect was also combined in one of the cases. 3. The atrial septal defect was corrected by, primary closure and the mitral valve was replaced with the prosthetic or bioprosthetic valve in all cases. The combined ventricular septal defect was closed using Teflon felt patch. 4. The operative result was good except in one who was expired of bacterial endocarditis 4 months after hospital discharge.

• Journal of Chest Surgery
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• v.7 no.2
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• pp.201-208
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• 1974

The purpose of this paper is to present author's experience with 6 cases of ruptured aneurysm of sinus of Valsalva which were treated surgically during last 10 years. Among the 6 cases, 5 were male and one was female. All of them originated from the right coronary sinus and 5 cases were ruptured into the RV while remained one into RA. The diagnosis was obtained in 4 cases by cineangiocardiogram. Clinically, we had difficulties in differential diagnosis with combined cases of VSD with A.I. and had special experience in its differentiation during cardiac catheterization. By simultaneous trans-venous and trans-arterial catheterization, identified two catheter tips in the RV, and pull back tracing obtained aortic pressure directly from RV, and RA from RV pressure which were benefit in confirm ruptured aneurysm of the aortic sinus. Surgical correction was performed by means of direct suture closure or combined Teflon pledget Of patch enforcement graft after aneurysm resection by trans-RA or trans-RV approach. All patients had no history of bacterial endocarditis, syphilis, or tuberculosis and operative findings revealed intact coronary sinus except involved one moreover 3 cases combined with high VSD which uggested congenital in origin although pathologic reports revealed only fibrosis. Post-operative course were uneventful in all cases but one who had bleeding and 2 months to 9 years follow up results were good and spend their usual life in all cases.

• Journal of Chest Surgery
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• v.48 no.5
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• pp.307-310
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• 2015

Background: To evaluate our experience of early surgical plication for diaphragmatic eventration (DE) in infancy and childhood. Methods: This study evaluated infants and children with symptomatic DE who underwent plication through an open transthoracic approach in our childhood development department between January 2005 and December 2012. Surgical plication was performed in several rows using polypropylene U-stitches with Teflon pledgets. Results: The study included 12 infants and children (7 boys and 5 girls) with symptomatic DE (9 congenital and 3 acquired). Reported symptoms included respiratory distress (91.7%), wheezing (75%), cough (66.7%), and recurrent pneumonia (50%). Preoperative mechanical ventilatory support was required in 41.7% of the patients. The mean length of hospital stay was $6.3{\pm}2.5days$. The mean follow-up period was $24.3{\pm}14.5months$. Preoperative symptoms were immediately relieved after surgery in 83.3% of patients and persisted in 16.7% of patients one year after surgery. All patients survived to the end of the two-year follow-up and none had recurrence of DE. Conclusion: Early diagnosis and surgical plication of the diaphragm for symptomatic congenital or acquired diaphragmatic eventration offers a good clinical outcome with no recurrence.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.1
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• pp.41-49
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• 2014

Pig chronic wasting disease, including porcine reproductive and respiratory syndrome (PRRS) and postweaning multisystemic wasting syndrome (PMWS), have made a continuous economic damage in pig farms. Airborne spread of livestock viruses are an important spread factor which is difficult to analyze due to invisible airflow and limitation of measurement. The objective of this study is to analyze airborne disease spread between buildings in the experimental pig farm by means of field experiment and computational fluid dynamics (CFD). The field experiments were conducted to capture airborne virus using air sampler and teflon filter along multi points in the experimental pig farm. The samples were tested in terms of virus detection resulting in positive reaction for PRRS and PCV-2 viruses, which can be a firm evidence of airborne virus spread. The CFD simulation model was developed by considering complex topography, wind conditions, building arrangement, and ventilation systems and was used to analyze airborne virus spread according to different wind conditions. The CFD computed result showed a possibility of airborne virus spread via livestock aerosol from infected pig house to neighboring pig houses according to wind directions. The CFD simulation technique is expected to provide significant data for estimating and making a counterplan against airborne disease spread.

• Journal of the Korean Magnetic Resonance Society
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• v.7 no.1
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• pp.62-67
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• 2003

MRI of laser-polarized $^{129}$ Xe under continuous flow conditions has recently been used for imaging of porous materials, however, any attempts at using a continuously circulating flow of laser-polarized $^3$He have not been made until now, presumably due to its extremely long spin exchange time (5-10 hrs). Since the inherent NMR sensitivity of $^3$He is 80 times greater than that of $^{129}$ Xe when considering the natural abundance, $^3$He can be expected to be a better nucleus for imaging than $^{129}$ Xe even under continuous flow conditions. In this report, the first MRI with continuously flowing laser-polarized $^3$He is shown for a phantom of Teflon tubing, demonstrating the feasibility of $^3$He imaging under continuous flow.

• Journal of Chest Surgery
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• v.10 no.1
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• pp.82-89
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• 1977

A rupture of a dissecting aneurysm of the aorta is life threatening disease and calls for emergency surgical treatment. The author recently experienced one case of ruptured dissecting aneurysm of the descending thoracic aorta complicated with left hemothorax who was recovered after emergency operation of Aug. 11, 1976. The patient was a 43 years old farmer with known hypertension [260/120] for 20 years but without any venereal disease and had experienced sudden throbbing chest pain. Chest film and aortogram revealed this case ruptured aneurysm of descending thoracic aorta complicated with left hemothorax. In this case, large dissecting aneurysm extend from proximal part of left subclavian artery below diaphragm and involved with 3.0 and 4.0cm sized elliptical rupture in proximal part of descending thoracic aorta. And so, neither fenestration procedure nor replacement of dacron artificial vessel was suitable for this case. Finally, only the rupture site of aneurysm was treated by covering with fibrous pleura and teflon patch. The post-operative management of this case was planned to control hypertension with antihypertensive drugs. The follow-up was possible up to date about 2months. The patient has been doing well with ordinary activities except mild chest discomfort.

• Progress in Superconductivity and Cryogenics
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• v.19 no.2
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• pp.53-57
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• 2017

In superconducting power devices including power cables in which high temperature superconducting (HTS) tapes are utilized, a reliable electrical insulation should be achieved for its maximum performance. For an efficient design of HTS superconducting devices, a comparative evaluation of the mechanical and thermal propperties for various insulation materials at cryogenic temperatures is required. Especially, in the process of the property evaluation of the sheet-shaped insulation materials, anisotropy according to the machining direction should be considered because the mechanical and thermal properties are significantly influenced by the sample orientation. In this study, the cryogenic thermal and mechanical properties of various insulation material sheets such as PPLP, Cryoflex, Teflon, and Kapton were determined considering sample orientation. All samples tested at cryogenic temperature showed significantly higher tensile strength as compared with that of room temperature. The ultimate tensile strength at both temperature conditions significantly depended upon the sample orientation. The thermal properties of the insulation materials exhibited a slight difference among samples depending on the orientation: for the PPLP and Cryoflex, the CD orientation showed larger thermal contraction up to 77 K as compared to the MD one. MD samples in PPLP and Cryoflex showed a lower CTE and thermal contraction which made it more promising as an insulation material due to its comparable CTE with HTS CC tapes.

• Journal of Environmental Science International
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• v.15 no.9
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• pp.847-853
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• 2006

In order to understand chemical characteristics and formation of dewfall in Busan, we analysed monthly distribution of dewfall, and investigated its chemical composition of dewfall. This study used the modified teflon plate $(1m{\times}1m)$ at Jangyongsil science high school from June 2005 to October 2005. In order to estimate qualitatively water soluble components, IC, ICP and UV methods for water soluble ions are also used respectively. Dewfall amount of sampling periods (26 day) collected 1.29 mm. Distribution of water soluble ions in dewfall founded the highest concentration $(81.3{\mu}eq/{\ell}\;for\;NO_3^-,\;146.6{\mu}eq/{\ell}\;for\;SO_4^{2-},\;and\;114.3{\mu}eq/{\ell}\;for\;nss-SO_4^{2-})$ during the June. pH was the lowest by 5.12 June, and October (pH 6.68) by most high and average pH was 5.46. Monthly equivalent ratio of $[SO_4^{2-}]/[NO_3^-]$ showed the highest value (2.94) during the September, the lowest value (1.77) during the July, and the mean value was 3.45.