• Proceedings of the KWS Conference
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• 1999.05a
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• pp.91-92
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• 1999

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.755-756
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• 2005

• International Journal of Vascular Biomedical Engineering
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• v.1 no.2
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• pp.36-41
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• 2003

Both flow visualizations and computational fluid dynamics were performed to determine hemodynamics in a total cavopulmonary connection (TCPC) model for surgically correcting congenital heart defects. From magnetic resonance images, an anatomically correct glass model was fabricated to visualize steady flow. The total flow rates were 4, 6 and 8L/min and flow rates from SVC and IVC were 40:60. The flow split ratio between LPA and RPA was varied by 70:30, 60:40 and 50:50. A pressure-based finite-volume software was used to solve steady flow dynamics in TCPC models. Results showed that superior vena cava(SVC) and inferior vena cava(IVC) flow merged directly to the intra-atrial conduit, creating two large vortices. Significant swirl motions were observed in the intra-atrial conduit and pulmonary arteries. Flow collision or swirling flow resulted in energy loss in TCPC models. In addition, a large intra-atrial channel or a sharp bend in TCPC geometries could influence on energy losses. Energy conservation was efficient when flow rates in pulmonary branches were balanced. In order to increase energy efficiency in Fontan operations, it is necessary to remove a flow collision in the intra-atrial channel and a sharp bend in the pulmonary bifurcation.

• English Language & Literature Teaching
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• no.6
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• pp.89-111
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• 2000

Since speaking is correlated with time and time is metaphorically conceptualized in terms of space, it is natural for us to conceptualize language metaphorically in terms of space. For example, we think that the future is in front and the past is behind. Reddy(1979) suggested in his conduit metaphor that linguistic expressions are containers. According to him, the speaker puts his ideas(objects) into words{containers)and sends them along a conduit to a hearer who takes the idea(object) out of the word(container). As a result we are able to know that the larger linguistic expressions have more meaning in it. In other words the space of a linguistic form has close relationship with meaning. Moreover we are able to see that formal distance between arguments or elements of linguistic expressions shows semantic influences between them. If two elements keep close distance, a preceeding element has a strong, direct and whole influence upon the following element. Sometimes even the results of the influence can be brought out implicitly by the formal relation between two elements. Therefore, the purpose of this paper is to show that tins difference in meaning which is due to formal distance of sentence elements can be explained by the metaphorical concept presented by Lakoff and Johnson(1980).

• Progress in Superconductivity and Cryogenics
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• v.19 no.4
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• pp.31-39
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• 2017

European R&D on designing their version of a DEMO fusion tokamak has recently resulted in the testing of a prototype $Nb_3Sn$ Cable-in-Conduit Conductor (CICC) for the DEMO TF coil. The characteristics and reported results of low temperature performance tests with the prototype CICC sample are compared with those from CICC samples incorporating other recent $Nb_3Sn$ cable designs. The EU-DEMO TF CICC prototype shows performance characteristics similar to that of the ITER CS CICC with short twist pitch. This is a first for a CICC sample that does not have a circular cross section. Assessment of its internal magnetostatic self-field suggests that a reduction in the internal self-field due to the rectangular geometry of the EU-DEMO TF CICC prototype compared to one with a circular geometry may have contributed to the performance characteristics showing current sharing temperature ($T_{cs}$) initially increase then stabilize with repeated electromagnetic loading, similarly to ITER CS CICC results. However, constraints on the internal self-field are not a sufficient condition for this $T_{cs}$ characteristic to occur.

• Journal of Chest Surgery
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• v.9 no.2
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• pp.271-275
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• 1976

Truncus arteriosus is a rare and highly lethal cardiac anomaly characterized by a single arterial trunk emerging from the heart and supplying the coronary, systemic, and pulmonary circulations, The first successful correction of truncus arteriosus was reported by McGoon et al. in 1968 and was based on experimental work reported by Rastelli et al. in 1967 in which a conduit consisting of a homograft of the ascending aorta and aortic valve was used to establish continuity between the right ventricle and the pulmonary arteries, Modification of this procedure using a Dacron tube valved with porcine xenograft instead of a homograft have resulted in the current definite treatment for truncus arteriosus. This report describes an 3 years and 4 months old boy with heart failure from type I truncus arteriosus who was diagnosed as the V. S. D. with pulmonary hypertension preoperatively and underwent corrective surgery employing the Rastelli procedure using a Dacron conduit valved with canine xenograft, but died due to massive bleeding from the anastomosis sites in operating room.

• Journal of Chest Surgery
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• v.36 no.10
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• pp.766-771
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• 2003

It is known that low birth weight is a risk factor for poor outcome in cardiac surgery for many cardiac defects. Truncus arteriosus is a rare congenital anomaly that has an unfavorable natural course. We report a successful surgical correction of truncus arteriosus in an 13-day-old premature infant with body weight of 1.5 kg and gestational age of 32 weeks. We used autologous untreated pericardial conduit without valve in right ventricular outflow reconstruction. The patients remains in good condition with normal body weight (50 percentile) and wide right ventricular outflow tract 20 months after the operation.

• Journal of Chest Surgery
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• v.33 no.5
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• pp.428-431
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• 2000

In the mid 1980's, the ITA(internal thoracic artery) graft was clearly recognized to be superior to the sapheonous vein graft in respect to long term patency. Therefore, there has been growing interest in the arterial conduit with the possibility of improving the long term result. We have been performing CABG with GEA since 1998 with the same purpose. For mid-term and long-term follow up, we have been performing postoperative coronary angiography. In this paper, a case of GEA spasm, a purported drawback of this conduit, during postoperative coronary anigiography and relieved by direct infusion of 200$\mu\textrm{g}$ isoket into the GEA is reported. The current case which exemplifies the spastic nature of RGEA is accompanied with coronary angiography.

• Journal of Chest Surgery
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• v.28 no.11
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• pp.1038-1044
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• 1995

We have been used cryopreserved homograft valves for right ventricular outflow tract[RVOT reconstruction since November 1993. The homograft valves were harvested from the hearts of brain dead patients or hearts of transplant recipients. There were 12 male and 10 female patients. Their ages ranged from 5 months to 13 years[mean age,39.2 $\pm$ 37.4 months and the weight ranged from 5 to 48kg [mean weight, 13.7$\pm$ 9. l kg . The diagnoses included pulmonary atresia with ventricular septal defect [n=14 , tetralogy of Fallot[n=4 , truncus arteriosus[n=3 , and double outlet right ventricle with pulmonic stenosis[n=l .Monocuspid homograft patches were used for RVOT widening or REV[reparation l`etage ventriculaire operations in 4 patients. We also used homograft as valved conduits for RVOT reconstruction in 17 patients and left ventricular outflow tract reconstruction in anatomically corrected transposition in 1 patient. Among them size-reducing technique [converting a tricuspid valved conduit into a bicuspid valved conduit were applied to six patients for the correction of size mismatching. The mean follow-up period was 10.6 $\pm$ 5.4 months. There was one operative death[4.5% due to bleeding and one reoperation for removal of vegetation on the homograft leaflet. Postoperative echocardiography documented no significant homograft insufficiency and RVOT obstructions.In short-term, the homograft valves provide excellent hemodynamic characteristics, even though further studies are necessary to evaluate the long-term results.

• Journal of Chest Surgery
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• v.11 no.3
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• pp.342-347
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• 1978

A 8 year old male was admitted to the Department of Thoracic Surgery, Korea University Hospital on June 22, 1978. The chief complaints were cyanosis and exertional dyspnea since at birth. EKG shows BVH and dextrocardia, phonocardiogram revealed the accentuation of second heart sound in aortic area. Echocardiogram from the left ventricle to the base of the heart, there is a discontinuity between the ventricular septum and the anterior aortic margin with a large aortic root & aortic overriding. His cardiac catheterization data and cardiac angiogram shows situs inversus totalis, dextrocardia, right aortic arch, large ventricular septal defect etc., and finally diagnosed Truncus Arteriosus. Edwards type IV with retrograde aortogram and selective bronchial angiogram. This is the first operative case reported as Rastelli operation for Truncus Arteriosus type IV in the literatures in Korea. Authors have experienced I case of Truncus Arteriosus, Edward type IV and Rastelli operation with Dacron Arterial Conduit Graft under cardiopulmonary bypass on July 3, 1978. The procedures were as follows; 2] Cardiopulmonary bypass: Origin of bronchial arteries excised from descending aorta bilaterally; defects in aorta closed. 2] Horizontal incision made high in right ventricle. 2] Ventricular septal defect [Kirklin type I+II] closed with Teflon patch. 4] Bifurcated dacron arterial graft with pericardial monocusp sutured to the bilateral pulmonary arteries. [Diameter 9 mm: Length 7 cm]. 5] Proximal end of the conduit graft anastomosed to right ventricle. [Diameter 19 mm: Length 5 cm]..Total perfusion time was 220 min. The result of operation was poor due to anastomotic leakage and increased pulmonary vascular resistance resulting acute right heart failure. The patient was died on the operation table. Literatures were briefly reviewed.