• 센서학회지
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• 제15권3호
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• pp.199-204
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• 2006

Carbon nanotube (CNT) mats grown by thermal chemical vapor deposition on a micromachined substrate with a chrome heater and a diaphragm were investigated as sensing materials of resistive gas sensors for nitrogen dioxide ($NO_{2}$) gas. The aligned CNT mats fabricated into mesh and serpentine shapes by the patterned cobalt catalyst layer. CNT mats showed a p-type electrical resistivity with decreasing electrical resistance upon exposure to $NO_{2}$. All sensors exhibited a reversible response at a thermal treatment temperature of $130^{\circ}C$ for about 5 minutes. The resistance change to $NO_{2}$ of the mesh-shaped CNT mats was larger than that of the serpentine-shaped CNT mats.

• Archives of Plastic Surgery
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• 제33권6호
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• pp.761-763
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• 2006

Purpose: Malignant peripheral nerve sheath tumors most often arise from the anatomically discernible peripheral nerve or neurofibroma. Methods: A 55-year-old man had a rapidly growing pedunculated large mass on the sacrolumbar junction for 2 years. He has congenital neurofibromatosis type I. He had multiple caf-au-lait spots and multiple neurofibromas on the entire body. The mass developed from a subcutaneous nodule on the sacrolumbar junction and grew rapidly. The preoperative punch biopsy revealed a malignant peripheral nerve tumor. The mass was completely excised with 1 cm free margin above the deep fascial plane. Results: There was no evidence of recurrence of tumor for 19 months of follow-up examination. Conclusion: Malignant peripheral nerve sheath tumor is very rare and has unique feature. We report a successful case of malignant peripheral nerve sheath tumor with the review of the literatures.

• 한국추진공학회지
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• 제24권2호
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• pp.52-60
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• 2020

본 논문에서는 개방형 액체로켓엔진의 제어 알고리즘을 다룬다. 이를 위해 엔진의 각 구성품들을 기준으로 수학적 모델링을 하였으며 추력제어를 위하여 연소실 압력을 피드백하여 제어시스템을 구축하였다. 제어시스템을 위하여 최대추력 상태에서 선형 모델을 이용하여 최적 출력피드백 LQ 추종 제어기를 설계하였으며 시뮬레이션을 통해 제어기의 성능을 검증하였다.

• 대한두경부종양학회지
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• 제23권2호
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• pp.165-169
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• 2007

Parathyroid gland tumor is an uncommon disease. The symptoms of parathyroid gland tumor appear in various features such as general weakness, renal stones, bone diseases and malignancies in some cases. We summarized the clinical features of 6 cases of parathyroid gland tumors with literatures.

• 대한두경부종양학회지
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• 제23권2호
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• pp.181-184
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• 2007

Hypopharyngeal cancer usually has invasiveness to adjacent tissue and frequent metastasis to cervical lymph node. In addition, because it often accompanies submucosal extension and second primary malignancy, the sacrifice of larynx and postoperative radiation therapy had been performed in the past. However, it has been reported that conservative surgery of hypopharyngeal cancer show good functional and oncologic outcome according to the development of diagnostic tool and reconstructive technique. We report a case of hypopharyngeal cancer that received conservative surgery followed radiation therapy and intraoperative radiation therapy for neck recurrence.

• 대한소아치과학회지
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• 제23권3호
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• pp.659-666
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• 1996

The treatment of complete avulsed teeth due to traumatic injuries is replantation procedure. The major complication of replantation are pulp necrosis, ankylosis, and root resorption. It is important to maintain the vitality of periodontal ligament to minimize the complications. The purpose of this case report is to consider the facts that affect the success rate and the prognosis of complete avulsed teeth after replantation. All of these cases had different conditions and transport media. The following results were observed: 1. The successive treatment of complete ayulsed teeth requires the maintainance of vitality of periodontal ligament. 2. The complication of replantation are inflammatory root resorption and ankylosis and in such case, proper endodontic treatment using calcium hydroxide medications and periodic observations are needed. 3. In case of delayed replantation, the use of fluoride and root planning procedure can help to achieve better result. 4. It is more esthetic and functional to maintain the avulsed tooth in mouth.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2006년도 춘계학술발표논문집
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• pp.203-206
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• 2006

The sensor consists of a heater, an insulating layer, a pair of contact electrodes, and CNT-sensing film on a micromachined diaphragm. The heater plays a role in the temperature change to modify sensor operation. Gas sensor responses of CNT-film to $NO_2$ at room temperature are reported. The sensor exhibits a reversible response with a time constant of a few minutes at thermal treatment temperature of $130^{\circ}C$.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2006년도 춘계학술발표논문집
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• pp.223-226
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• 2006

The micro-gas sensor based on carbon nanotubes (CNTs) was fabricated and its gas sensing characteristics on nitrogen dioxide ($NO_2$) have been investigated. The sensor consists of a heater, an insulating layer, a pair of contact electrodes, and CNT-sensing film on a micromachined diaphragm. The heater plays a role in the temperature change to modify sensor operation. Gas sensor responses of CNT-film to $NO_2$ at room temperature are reported. The sensor exhibits a reversible response with a time constant of a few minutes at thermal treatment temperature of $130^{\circ}C$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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• pp.111-115
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• 2002

To understand the discharge characteristics in AC-PDP, it is necessary to study on the wall charge behavior. But, it is difficult to measure the wall charge directly. In this paper, the V-Q Lissajous' figure is used to measure the wall charge indirectly and analyze the wall charge behavior. With the V-Q Lissajous' figure, the discharge characteristics of AC-PDP are studied according to vary driving conditions, such as the frequency, pulse duty ratio, and rising & falling time. As a result, the V-Q Lissajous' figure is used to measure the discharge characteristics of the AC-PDP. It is confirmed that firing initial voltage and firing final voltage for discharge are effected by the aboved variables. Related with the wall voltage generation, it is thought that the difference of the slope at the V-Q Lissajous' figure is caused by charged ions inside the dielectric layer.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2015년도 학술발표회
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• pp.84-88
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• 2015

경인 아라뱃길은 국내에서 운영된 사례가 없는 기수역 운하로서 유량 및 수환경 관리 등을 포함한 수질관리 상황을 종합적으로 평가하기 위한 대책이 필요하다. 또한 경인 아라뱃길로 유입되는 오염원에 대한 현황 및 현장조사를 실시하고, 유입 오염원인을 정확히 파악하는 것이 중요하다. 따라서 경인 아라뱃길 유역의 수질조사 및 분석, 수질예측을 통해 수질관리 방안을 제시하였다. 분석결과, 홍수시 경인 아라뱃길로 유입되는 굴포천의 DO, BOD, SS는 삼정천의 영향으로 상승하였다. 삼정천은 굴포천 상류에서 부천시와 인천시의 관할 행정구역 면적에 비해 인구밀도가 높고 축산 농가 및 산업계로 인한 미처리 유출수에 의해 굴포천에 직 간접적인 영향을 미치고 있는 것으로 판단된다. 또한 굴포천 하수처리장 방류 이후 BOD, T-N, T-P의 경우 급상승하였다. 따라서 굴포천 중류의 부천시 삼정동과 인천시 계양구 내 하수 및 폐수를 하수처리장을 통해 배출할 수 있는 공동처리장 운영 등의 처리 방안이 필요하다. 또한 EFDC 모형을 이용한 해수와 담수의 성분비 변화에 대한 경인 아라뱃길의 수질을 예측한 결과, 해수가 많을수록 수질이 BOD, COD 등이 양호 한 것으로 나타났다. 그러나, 염분에 의한 지하수 및 주변환경 변화에 대한 영향을 고려하였을 때, 해수와 담수비를 조절하는 것보다 성분비를 유지하고 유입되는 양을 확대한다면, 경인 아라뱃길의 수질관리는 효과적일 것으로 판단한다.