• Journal of Chest Surgery
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• 제23권3호
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• pp.430-437
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• 1990

We clinically evaluated 121 cases of ventricular septal defect which we operated from April, 1986 to December, 1989 at Inha General Hospital, Seong-Nam, Department of Thoracic and Cardiovascular Surgery, College of Medicine, Inha University. These patients were occupied 54.8% of all congenital heart diseases operated on its same period. Of the 121 patients, 63 patients were male[52.1%] and 58 patients were female[47.9i]. The two most common symptoms were frequent upper respiratory infection and dyspnea on exertion. By Kirklin s anatomical classification, type I constituted 34.7%, type II 61.98%, type III 0.03% and type IV not occupied. Associated cardiac anomalies were found in 34 cases, and PDA was most common associated anomaly, occupied in 22 cases. On the cardiac catheterization data, there were statistically significant correlation between VSD size[cm2 /BSAm2] and systolic pulmonary arterial pressure[sPAP], pulmonary to systemic flow ratio[Qp/Qs] & pulmonary to systemic pressure ratio[Pp/Ps] respectively, Type II [r=0.53, p<0.01] was more correlated than type I [r=0.49, p<0.05] between VSD size and Qp /Qs. We could not found the correlationship between age and Qp/Qs [Type I; r=0.16, Type II; r=-0.15] All cases were operated under cardiopulmonary bypass and 58 cases[46.3%] were operated through the right atrial approach, and 34 cases[28.1%] through the pulmonary arterial approach. Operative mortality rate was 4.13%[5 cases].

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.294-298
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• 2008

Snow cover is a potential water resource for later spring and summer seasons as well as a thermal mirror with high reflectivity causing decreases of surface air temperature during cold winter seasons. In this study, current and future changes in Northern Hemisphere snow extent and their potential linkages with atmospheric circulation are examined. The NOAA AVHRR visible snow extent (1967-2006) data as well as observational (NCEP-DOE 1979-2006) and modeled (GFDL 2.1 2081-2100) pressure and surface air temperature data are used. Analyses of observational data demonstrate that the snow extent in meteorological spring (March to April) and summer (June to August) has significantly decreased since the late 1980s. The offset of snow seasons (the timing of snow melt in spring) have also significantly advanced particularly in Europe, East Asia, and northwestern North America. Analyses of pressure fields reveal that the spatial patterns of the earlier snow melt are associated with changes in atmospheric circulation such as the Arctic Oscillation (AO). In the positive winter AO years, multiple positive pressure departure cores in the upper troposphere (200hPa) are observed over the mid-latitude regions from March to mid-April, while a negative pressure departure core (70hPa) prevails over the Arctic Ocean. The reversed anomaly patterns related to later snow melt occur in negative winter AO years. The comparison between current and future thermal spring onsets suggest that snow melt patterns will intensify with larger greenhouse gas emissions, indicating earlier hydrological spring onset.

• 한국수자원학회논문집
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• 제39권1호
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• pp.35-46
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• 2006

본 연구에서는 안전하고 원활한 용수공급을 목적으로 하는 상수도관망시스템의 오염예방 및 위험관리를 위한 통합의사결정시스템의 기본구조를 제시하고 유럽과 미국에서 널리 사용되고 있는 다기준 의사결정기법인 PROMETHEE와 ANP를 적용해 상수도관망의 이상징후 판정을 위한 위험요소들의 우선순위를 평가하였다. 문제 구성을 위하여 pH 잔류염소농도, 유량, 수압, 전기전도도, 탁도, 블록누수량, 수온을 자료항목으로 선정하였고 관부식, 관파열, 관내수질오염을 평가기준으로 하여 PROMETHEE와 ANP의 결과를 비교 분석하였다. 본 연구에서 제시한 상수도관망의 위험요소 평가결과는 위기상황 대처방안시스템 구축시 사고대응 제어알고리즘 설계의 기초자료가 될 수 있을 것이다.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1676-1685
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• 2021

We develop a new high-fidelity multiphysics model to simulate boron chemistry in the porous Chalk River Unidentified Deposit (CRUD) deposits. Heat transfer, capillary flow, solute transport, and chemical reactions are fully coupled. The evaporation of coolant in the deposits is included in governing equations modified by the volume-averaged assumption of wick boiling. The axial offset anomaly (AOA) of the Seabrook nuclear power plant is simulated. The new model reasonably predicts the distributions of temperature, pressure, velocity, volumetric boiling heat density, and chemical concentrations. In the thicker CRUD regions, 60% of the total heat is removed by evaporative heat transfer, causing boron species accumulation. The new model successfully shows the quantitative effect of coolant evaporation on the local distributions of boron. The total amount of boron in the CRUD layer increases by a factor of 1.21 when an evaporation-driven increase of soluble and precipitated boron concentrations is reflected. In addition, the concentrations of B(OH)₃ and LiBO₂ are estimated according to various conditions such as different CRUD thickness and porosity. At the end of the cycle in the AOA case, the total mass of boron incorporated in CRUD deposits of a reference single fuel rod is estimated to be about 0.5 mg.

• 대한기계학회논문집B
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• 제28권10호
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• pp.1279-1287
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• 2004

The vaporization characteristics of a liquid heptane droplet in a supercritical nitrogen flow are numerically studied. The transient conservation equations of mass, momentum, energy, and species are expressed in an axisymmetric coordinate system. The governing equations are solved time marching method with preconditioning scheme. The modified Soave-Redlich-Kwong equation of state is employed for taking account of real gas effects such as thermodynamic non-ideality and transport anomaly. Changing the convective velocity and ambient pressure, several parametric studies are conducted. The numerical results show that the two parameters, Reynolds number and dimensionless combined parameter(${\mu}$s/${\mu}$d)(equation omitted), have influence on supercritical droplet vaporization.

• Journal of Chest Surgery
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• 제18권2호
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• pp.314-319
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• 1985

Nineteen patients with various types of cyanotic congenital heart disease underwent systemic-pulmonary artery shunts with a microporous polytetrafluoroethylene [PTFE] graft between September, 1983, and April, 1985. Age ranged from 3 months to 18 years, and seven of them were less than 12 months old. There were seventeen Great Ormond Street type of modified Blalock-Taussig shunts, and two central polytetrafluoroethylene shunt [ascending aorta-right pulmonary artery]. There was one postoperative death [1/19=5.3%] in a 10 Kg child born with pulmonary atresia and ventricular septal defect associated with patent ductus arteriosus. He had another anomaly of imperforated anus. Relief from cyanosis was achieved in other eighteen patients with variable degree. Eighteen survivors have been followed up from 1 month to 19 months. Clinical status, auscultation, oxygen partial pressure of arterial blood, and hemoglobin have been used to establish shunt patency in all survivors. By above criteria, all survivors have good patent shunt.

• Journal of Chest Surgery
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• 제20권1호
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• pp.218-222
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• 1987

Unroofed coronary sinus syndrome is an uncommon anomaly, Unroofed coronary sinus syndrome is caused by incomplete formation of the left atriovenous fold, and it usually is associated with Left SVC. If it is not diagnosed, a residual reversed or bidirectional shunt will result, and its complications will reduce life expectancy. We experienced 3 cases of unroofed coronary sinus syndrome which combines TOF with PLSVC, partial ECD, primum type ASD. In case of Unroofed coronary sinus syndrome which combines TIF with PLSVC, preoperative diagnosis was not made. In corrective operation for TOF of this case, pump weaning was failed due to hypoxia and cardiac arrest, and he expired at operation room. At autopsy of this case, complete unroofed coronary sinus was found. In the other 2 cases, partial unroofed coronary sinus syndrome was found in operation field and corrective operation was performed successfully. We report these 3 experiences with its review. ^u ++ Noninvasive Assessment of Pressure Gradients across Prosthetic Heart Valve by Doppler Ultrasound - A comparative study of the Duromedics Bileaflet Valves in mitral position and Normal Mitral Valves -with its review.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.1023-1026
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• 2006

As it was shown recently, climate changes in Antarctica resulted in interannual trends of some climatic parameters like sea level pressure, surface air temperature, ice thickness and others. These tendencies have effect on the Southern Ocean meteorological and hydrological regime. The following remote sensing data: AVHRR MCSST data, satellite altimetry data (merged data of mission ERS-2, TOPEX/Poseidon, Jason-1, ENVISAT, GFO-1) are used to analyse the interannual and/or climatic tendency of sea surface temperature (SST) and sea level anomaly (SLA). According to the obtained results, SST has negative trend $-0.02{\pm}0.003^{\circ}C/yr$ for 24-yr record (1982-2005) and SLA has positive trend $0.01{\pm}0.005$ cm/yr for 24-yr record (1982-2005) and $0.24{\pm}0.026$ cm/yr for 12-yr record (1993-2005). However in some areas (for example, Pacific-Antarctic Ridge) SST and SLA tendencies are stronger $-0.065{\pm}0.007^{\circ}C/yr$ and $-0.21{\pm}0.05$ cm/yr, respectively.

• Journal of Chest Surgery
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• 제11권1호
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• pp.75-80
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• 1978

Coarctation of the aorta, a well known congenital cardiovascular defect, can be recognized in most instances by simple findings of physical examination. This condition shortens life if untreated, but it can be corrected surgically to render the patient functionally normal. It seems relatively rare in Asian. We experienced two cases of coarctation of the aorta which were treated surgically. The first case was 17 years old male with juxtaductal type of coarctation of the aorta. The second was 7 years old female with preductal type of coarctation of the aorta and combined anomaly of PDA and she had been in congestive heart failure. In both cases, coarctated segments of the aorta were resected and end to end anastomosis were performed. In the second case, PDA was closed by division before resection of the coarctated segment. The postoperative courses were uneventful. They discharged 2 weeks postoperatively without any complications. Blood pressure was nearly normalized at the time of follow up check.

• Journal of Chest Surgery
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• 제19권4호
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• pp.578-583
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• 1986

Tetralogy of Fallot is the most common cyanotic congenital anomaly, which needs some operation for the survival. Perioperative mortality of the Tetralogy of Fallot was lowered remarkably in recent years, but some discussions were presented for the criteria of the corrective surgery and the corrective method of the pulmonary stenosis. In the Department of Thoracic and Cardiovascular Surgery of the Chunbug National University Hospital, 17 cases of tetralogy of Fallot were corrected totally from July in 1983 to August in 1984. In correction of the pulmonary stenosis, transannular patch was applied in B patients, infundibulectomy in 5, RVOT patch without transannular patch in 3, and isolated patches on RVOT and pulmonary trunk. Preoperative and early postoperative hemodynamic study revealed increased RA pressure in transannular patch group, which was significant statistically. [p<0.01]. Clinically, perioperative death occurred only in transannular patch group, and right heart failure signs including hepatomegaly, ascites, pleural effusion and peripheral edema were high in frequency in transannular patch group.