• 한국환경과학회지
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• 제3권4호
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• pp.417-425
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• 1994

Leachate from municipal landfill site is known to be hard to treat because it commonly contains various toxic material and heavy metals. In addition, portions of biodegradable organic substances in leachate are decreasing in the course of wastes stabilization, which is one of the critical reason for inefficient biological treatment at the end stage of landfill site operation. So this study was conducted to examine the feasibility of municipal lanuill leachate pretreatment using electrolysis. The optimum electrode combination was made. The optimum electrode combination was found to be lead and graphite.

• 대한치과의사협회지
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• 제33권4호통권311호
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• pp.264-273
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• 1995

2000년대에 있어서 세계의학계는 인공심장의 완성과 인공신장, 인공 간, 인공수족과 인공골, 관절, 혈관 등의 인공장기이식의 눈부신 연구, 발전에 의하여 인간의 수명은 더욱 연장될 것이며 사망률을 낮추는 치료의학은 한없이 발전하게 될 것이다. 치과의학의 과제는 상실된 치아와 악골, 구강내외 장기의 수복을 위한 인공치아 및 장기이식의 치료요법의 발전이 될 것이다. 인공치아 치료요법의 한가지인 nonsubmerged and one stage operation type인 I.T.I. 임프란트 시스템은 골성접착과 결합이 이루어지는 인공치아 이식술로서 그 단순한 시술과 높은 성공률에 의해 전세계에 각광을 받는 치료방법의 하나이다.

• Journal of Chest Surgery
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• 제23권3호
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• pp.546-549
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• 1990

Spontaneous esophageal perforation occurred rarely but often lead to a high mortality and morbidity. We had experienced one case of spontaneous rupture of esophagus. A 52 - year old male patient was admitted to our hospital because of the chest pain and massive hematemesis after emetic strain. Esophagogram that taken at private clinic revealed leakage of dye into the right pleural space. Under the diagnosis of the thoracic esophageal perforation, two stage operation was planned because the size of perforation was large and pyothorax was developed on the right side. At first, exclusion and diversion of the esophagus were carried out. After six months, the esophageal reconstruction with left colon was performed.

• Journal of Chest Surgery
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• 제37권4호
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• pp.313-321
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• 2004

폐동맥하 심실중격결손을 동반한 양대혈관 우심실기시증에서 동맥전환술은 심실내 교정의 제한된 적응증과 동맥전환술의 우수한 임상성적으로 인해 최근 이 기형의 선택적 치료법으로 자리잡고 있다. 이 기형에 대한 동맥전환술의 단기 및 중기 성적을 검토하였다. 대상 및 방법 1994년 8월부터 2002년 7월까지 8년 동안 동아대학교 병원에서 심실중격결손증 교정과 동맥전환술을 시행한 폐동맥하 심실중격결손을 동반한 양대혈관 우심실기시증 환자 13명을 대상으로 후향적 조사를 하였다. 양대혈관 우심실기시의 진단은 50% rule을 적용하였다. 중심나이와 평균체증은 각각 27일(범위, 3-120일)과 3.8$\pm$0.7kg (범위, 2.92-5.3kg)이었다. 대동맥궁기형은 6명(46.2%)에서 동반되었고 모두 일차 완전교정(one-stage repair)으로 교정되었다. 양대혈관의 위치관계는 좌우로 위치한 것이 8예(61.5%), 전후로 위치한 것이 5예(38.5%)였다. 관상동맥의 형태는 1LCx-2R과 좌관상동맥이 폐동맥의 뒤로 돌아가는 형태가 각각 6예씩(46.2%)이었으며 1명(7.7%)에서 벽속 좌관상동맥기형이 관찰되었다. 심실중격결손의 확장 및 패치를 이용한 우심실유출로 성형술이 각각 1명(7.7%)에서 시행되었다 좌우 대혈관 위치관계를 갖고 있는 3명(23.1%)을 제외한 모든 환자에서 Lecompte 술식을 시행하였다. 결과: 3예(23.1%)의 수술사망이 발생하였다. 3예 모두 대동맥궁기형을 갖고 있었던 경우였다. 수술 생존자의 평균추적기간 41.3$\pm$30.7개월(범위 1.7-79.1개월) 동안 만기사망은 1예(10%)로 술 후 5개월 뒤 중추신경계 합병증으로 사망하였다. 1예(10.0%)에서 압력차 30mmHg 이상의 폐동맥판 협착이 발견되었고 2예에서 좌폐동맥 협착으로 풍선확장술이 필요하였으며 이 중 1예(10%)에서 술 후 52개월만에 재수술이 필요하였다. 무증상의 중등도 대동맥판 폐쇄부전증이 1예(10%)에서 발견되었다. 수술사망을 포함한 5년 생존율은 68.3%였다. 결론: 대동맥궁기형을 동반한 폐동맥하 심실중격결손의 양대혈관 우심실기시증 환자에서는 높은 수술사망률을 보였으나 동반하지 않은 경우는 낮은 수술사망률과 재수술률을 보여 동맥전환술이 이 심기형에서 유용한 수술방법으로 고려될 수 있을 것이라고 생각한다.

• Journal of Chest Surgery
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• 제18권3호
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• pp.506-512
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• 1985

We have experienced 120 non-small cell primary carcinomas of the lung between June, 1974 and December, 1984, at Seoul National University Hospital. They were 107 males and 13 females. 95% of all were ranged from 40 years to 69 years of age with 56 years of mean age. They were composed of 70 [66.7%] squamous cell ca., 20 [19%] adenoca., 6 [5.7%] undifferentiated large cell ca., 4 [3.8%] undifferentiated small cell ca., and 5 [4.8%] mixed adenosquamous cell ca. 41 [36%] and 35 [30.7%] patients have received pneumonectomies and lobectomies with a 66.7% resectability rate. Of the 36 stage I and 21 stage II patients, 56 were resectable but only 20 [31.7%] of the 63 stage III patients were resectable. This informed us the significance of the stage of the disease at the time of operation. The actuarial survival rate in 70 patients was as follow: 1, 3, 5 year survival rate of the patients in stage I were 80%, 80%, and 60% respectively. Both 1, 3 year survival rate of patients in stage II were 84%. But 1, 2, 3 year survival rate of patients in stage III were 40%, 11%, and 5% respectively. By dividing the patients in stage III into resectable group and nonresectable one, both 1, 2 year survival rate of the former were 37% and those of the latter were 42% and 7%. According to the cell type of the cancer, 1, 3, 5 year survival rate of the squamous cell ca. were 63%, 40%, and 26% respectively. 1, 3 year survival rate of the adenoca. were 43% and 34%. Hospital death were only 2 cases with a 1.7% operative mortality rate. We had acceptable long-term survival rate and have convinced the necessity and hope of the early detection and resection of the lung carcinoma.

• 한국정보통신학회논문지
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• 제16권4호
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• pp.771-777
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• 2012

본 논문에서는 공통 연산기(Common Operation Unit)를 이용한 CABAC의 이진 산술 부호화기를 제안한다. 제안한 공통 연산기는 모드에 상관없이 하나의 공통 연산기를 이용하여 산술 부호화 및 재정규화를 수행하는 이진 산술 부호화기의 하드웨어 구조를 단순하게 구현할 수 있다. 제안하는 CABAC의 이진 산술 부호화기는 Context RAM, Context Updater, Common Operation Unit, Bit-Gen으로 구성되며 매 클럭당 하나의 심볼이 부호화될 수 있는 4단 파이프라인으로 구성하였다. 제안한 CABAC의 이진 산술 부호화기는 기존 CABAC의 이진 산술 부호화기와 비교하여 게이트 수는 최대 47% 감소하였고, 동작 주파수는 최대 19% 성능이 향상됨을 확인하였다.

• Transactions on Electrical and Electronic Materials
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• 제10권2호
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• pp.44-48
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• 2009

A simulation study of a 10-bit two-stage DAC was done by using a conventional current switch cell. The DAC adopts the segmented architecture in order to reduce the circuit complexity and the die area. The 10-bit CMOS DAC was designed in 2 blocks, a unary cell matrix for 6 MSBs and a binary weighted array for 4 LSBs, for fabrication in a 0.35-${\mu}m$ CMOS process. To cancel the accumulation of errors in each current cell, a symmetrical switching sequence is applied in the unary cell matrix for 6 MSBs. To ensure high-speed operation, a decoding circuit with one stage latch and a cascode current source were developed. Simulations show that the maximum power consumption of the 10-bit DAC is 74 mW with a sampling frequency of 100 MHz.

• 환경위생공학
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• 제13권2호
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• pp.57-65
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• 1998

In this research, Effect of C/N ratio on nutrient removal in intermittently aerated activated sludge system(IAASS) was investigated with dormitary, building and swine wastewater. Three types (2-stage, 4-stage, modified) of IAASS were operated. Time interval of aeration/nonaeration in IAASS was 1hr/1hr. In treatment of Dormitary wastewater(BOD/T-N ratio : 4.4), Building wastewater (BOD/T-N ratio : 3.14) and swine wastewater(BOD/T-N ratio : 3.84), Nitrogen removal efficiency of 80, 70 and 90.4% was achieved, respectively. Nitrogen removal in IAASS was a great influenced on influent C/N ratio, efficient nitrogen removal was achieved at BOD/T-N ratio over 4. In IAASS operation, $\Delta $BOD mg/L/$\Delta $ nitrogen mg/L ratio was about 4-6. Simultaneous removal of organic, nitrogen and phosphorus in IAASS can achieved. And influent organic was efficiently utilized in denitrification. IAASS could be one of the best alternative process for the retrofit of conventional activated sludge system for the removal of nutrients.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.2205-2210
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• 2003

The 1st stage bucket of the 170MW simple cycle gas turbine is one of the components that is normally run in exposed state at the highest thermally stressful environment while the turbine is operating. After certain period operation, various type of damages are easily found and the damages are identified as due to the turbine operating mode of which the demand of the electricity power is very peaking and cyclic. Since this trend is more evident at some part of power plants in Korea and it has caused higher scrap rate of the bucket at the first repair interval than other country. Therefore, demand for the higher capability and alternative technologies which allow salvaging more buckets and preventing from severe damages is always high. In this study, a review and estimation of the repair technologies for the past 5 years to present have been conducted and show results.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.694-700
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• 1998

A novel zero-voltage-transition (ZVT) isolated PWM boost converter for single stage power factor correction (PFC) is presented to improve the performance of the previously presented ZVT converter[8]. A simple auxiliary circuit which includes only one active switch provides zero-voltage-switching (ZVS) condition to all semiconductor devices. (Two active switches are required for the previous ZVT converter) This leads to reduced cost and simplified control circuit comparing to the previous ZVT converter. The ZVS is achieved for wide line and load ranges with minimum device voltage and current stresses. Operation principle, control strategy and features of the proposed converter are presented and verified by the experimental results from a 1.5 kW, 100 KHz laboratory prototype.