• Journal of Chest Surgery
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• 제31권7호
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• pp.650-659
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• 1998

부천세종병원에서는 '96년 8월부터 '97년 8월까지 22명의 환자에게 심장외폰탄 (extracardiac Fontan) 수술을 시행하였다. 남자 14명, 여자 8명이었으며, 진단별로는 단심실증 16명(우심실형 12명, 좌심실형 4명), 삼첨판폐쇄증 4명, 좌측이소성(left isomerism), 대혈관전위증, 심실중격결손증이 있으면서 폐동맥협착증이 있는 환자 1명, 그리고 Criss-Cross 심장이면서 비대칭심실이 있는 1명이었다. 연령은 22개월부터 26세까지 분포하였고 폐동맥압은 평균 11.7$\pm$3.1 mmHg이었다. 선행수술로 양방향성대정맥폐동맥단락술(bidirectional cavopulmonary shunt)을 시행한 환자가 15명으로 평균 15.6$\pm$3.4개월의 기간을 두고 수술을 시행하였고, 고전적 글렌 수술 후 14년만에 Fontan 수술을 시행한 환자가 1명 있었다. 전대정맥폐동맥단락술(total cavopulmonary shunt, Kawashima operation)후 폐동-정맥루(pulmonary arteriovenous fistula) 발생으로 평균 37.5$\pm$20개월만에 수술을 받은 환자가 4명 있었고, 2명의 환자는 선행수술 없이 심장외폰탄수술을 시행하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.71-72
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• 2008

This paper describes a circuit based simulation model for a Photovoltaic(PV) cell in order to estimate the electrical behavior of the solar cell module with changes of environmental parameters such as shunt resistance, series resistance, temperature and irradiance. An accurate I-V model of PV module is presented based on the Shockley diode model. The general model was implemented on Matlab scrip file, and used irradiance and temperature as variables and outputs of the I-V characteristic. A typical PV module was used for the evaluation, and results was compared with reference taken directly from the manufacturer's published curves leading to excellent agrement with the theoretical prediction.

• Current Photovoltaic Research
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• 제1권1호
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• pp.59-62
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• 2013

We investigated the effects of ZnO thin film deposition methods on the performance of inverted polymer solar cells with a structure of ITO/ZnO/P3HT:PCBM/MoO3/Al. The ZnO thin films were deposited by various methods (spin coating of nanoparticles, sol-gel process, atomic layer deposition) and their morphology was analyzed by atomic force microscopy (AFM). The device with ZnO nanoparticle thin films showed the highest power conversion efficiency of 3 % with low series resistance and high shunt resistance. The superior performance of the device with the ZnO nanoparticle layer is attributed to better electron extraction capability.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.3-4
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• 2008

Photovoltaic module consists of serially connected solar cell which has low voltage characteristics. But, the other way, the whole current flow of PV module is restricted by lowest current of one solar cell. For the experiment, we make PV module composing the solar cells that have short circuit current difference of 0%, 1%, 3% and 5%. Using Light I-V and Dark I-V measurements, electrical characteristic parameters like Isc(short-circuit current), Voc(open-circuit voltage), Rs(series resistance), Rsh(shunt resistance) are analyzed. PV module of low current characteristics has electrical stress from other modules. And, such a module has a tendency of hot-spot suffering which leads degradation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1992년도 춘계학술대회 논문집
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• pp.105-109
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• 1992

ITO film, 1500${\AA}$ of thickness, onto glass and p-InP wafer was prepared by e-beam evaporator. The bet ITO film had the resistivity 5.3${\times}$10$\^$-3/ $\Omega$-cm, the concentration 6.5${\times}$10$\^$20/cm$\^$-3/, the transmittance above 80%, and the optical energy gap about 3.5eV. The higher pressure of injected oxygen, the less reverse bias saturation current and the more open circuit voltage. Under the optimum evaporation conditions, the efficiency was 7.19% and the series resistance, and the shunt resistance were respectively 8.5%, 3${\alpha}$, and 26K$\Omega$. The interdependence between activation energy and pre-exponential factor was found. We found he surface of the p-InP became n-type and consquently supposed that the buried homojunction formation, that is, n+-ITO/n-InP/p-InP was caused by Sn diffusion or loss of phosphorus in the interface layer.

• 전력전자학회논문지
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• 제19권1호
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• pp.51-56
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• 2014

PV cell modeling is necessary both for software and hardware simulators in analyzing and testing the performance of PV generation systems. Unique I-V curve of a PV cell identifies its own characteristics by electrical equivalent model that is composed of diode constants ($I_o$, $v_t$), photo-generated current ($I_{ph}$), series resistance ($R_s$), and shunt resistance ($R_{sh}$). Photo-generated current can be easily estimated since it is proportional to irradiation level. However, other electrical parameters should be solved from the manufacturer's data sheet that is consisted with three remarkable operating points such as open circuit voltage ($V_{oc}$), short circuit current ($I_{sc}$), and maximum power voltage/current ($V_{MPP}/I_{MPP}$). This paper explains and analyzes mathematical process of a novel PV cell modeling algorithm that was proposed by the authors with the name of "K-algorithm".

• 한국전기전자재료학회논문지
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• 제24권10호
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• pp.844-849
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• 2011

Two kind of Ag-pastes were prepared for integrating the bulk Si solar cell. One is the Ag-paste with Pb-based glass frit and the other is that with Bi-based glass frit. The pastes were the mixture of 84 wt% Ag, 2 wt% glass frit, 11 wt% solvent of buthyl cabitol acetate, and 2 wt% additives. After fabricating the Ag-pastes, they was coated on a $SiN_x$/n+/p- stacks of a commercial mono-Si solar cell. The solar cell efficiency was 17.6% in the case of the Pb-based Ag-paste. However that was 16.2% in the solar cell integrated with the Bi-based Ag-paste. The lower performance in Bi-based Ag-paste was caused by the higher series resistance and the lower shunt resistance in comparison with the Pb-based Ag-paste.

• Journal of Chest Surgery
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• 제24권3호
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• pp.310-321
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• 1991

Between April 1986 and September 1990, 34 patients with a single or dominant right ventricle underwent modified Fontan procedure for definite palliation in Seoul National University Children`s Hospital. Their age at operation ranged from 8 months to 14 years [Mean 5.5 years]. The ventricular chamber was solitary and of indeterminate trabecular pattern in 6 patients. 28 patients had posteriorly located rudimentary chamber, all of which were trabecular pouches having no communication with outlet septum. The patterns of atrioventricular connection were common inlet[9], double inlet [11], left atrioventricular valve atresia [12] and right atrioventricular valve atresia with L-loop [2]. Pulmonary outflow tracts were atretic in 7 patients and stenotic in 26 patients. Major associated anomalies included anomalous systemic venous drainage [15], dextrocardia [12] and total anomalous pulmonary venous connection[3]. Shunt operations were previously performed in 13 patients and pulmonary artery banding and atrial septectomy in 1 patients. Surgery included intraatrial baffling in 26 patients, bidirectional cavopulmonary shunt in 13 patients, atrioventricular valve obliteration in 3 patients and atrioventricular valve replacement in 3 patients. Central venous pressure measured postoperatively at intensive care unit ranged from 18cm H2O to 28cm H2O [mean 23.2cm H2O]. Hospital mortality was 35.3% [12/34], all died out of low output syndrome. Suspected causes of low output syndrome include ventricular dysfunction [8], hypoplastic or tortuous pulmonary artery [2] and elevated pulmonary vascular resistance [2]. 19 patients had 31 major complications including low output syndrome [18], arrhythmia [4], acute renal failure [3] and respiratory failure [3]. Mortality rate was significantly higher in the groups receiving intraatrial baffling and AV valve replacement respectively [p<0.05]. 20 patients were followed up postoperatively with the mean follow-up period 15.0$\pm$11.6 months. There were no late death and follow-up catheterization was performed in 10 patients. Mean right atrial pressure was 15.4$\pm$6.8mmHg and ventricular contraction was reasonable in all but one case. Thus, Fontan principle can be applied successfully to all the patients with complex cardiac anomaly of single ventricle variety and better results can be anticipated with judicious selection of patient and improvement of postoperative care.

• Journal of Chest Surgery
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• 제17권2호
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• pp.250-256
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• 1984

Eisenmenger syndrome is a condition which systemic arterial blood oxygen unsaturation occurs if obstruction in the pulmonary capillaries raises the pulmonary vascular resistance and pulmonary arterial pressure to or beyond systemic levels and then a significant right to left shunt develops across a preexisting cardiac septal defect or an aortopulmonary communication-We have experienced 3 cases of similar condition. Case I is 24 year old man who has had cyanosis and dyspnea on exertion since childhood. His pulmonary arterial pressure was 110/80mmHg. He was operated under diagnosis of the mitral stenosis and tetralogy of Fallot, but it was finally discovered that he had patent ductus arteriosus and ventricular defect was closed with perforated prosthetic patch, but the patient expired due to right heart failure low cardiac output. Case II was 16 year old female who had pulmonary hypertension of 110/85mmHg. She was diagnosed as Eisenmenger syndrome combining with atrial septal defect and patent ductus arteriosus. Case III was 20 year old male. His pulmonary arterial pressure was 110/70mmHg and the underlying defect was patent ductus arteriosus.

• Journal of Chest Surgery
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• 제37권6호
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• pp.539-542
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• 2004

폐동맥 형태가 비정상적이거나 폐동맥 저항이 높은 경우뿐 아니라 주요 대동맥-폐동맥 측부혈관은 폰탄 수술의 위험을 높이는 인자로 알려져 있다. 저자들은 기능적 단심실과 더불어 양측 폐동맥의 발달이 매우 미약하고 양측 폐의 대부분을 주요 체-폐동맥 부행혈관에 의해 혈류가 공급되는 고위험 폰탄수술 환자에서, 단일초점화수술과 체폐동맥 단락술로 폐동맥 재건과 단계적 수술을 거쳐 성공적으로 폰탄수술에 이르렀기에 이를 보고하는 바이다.