• Radiation Oncology Journal
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• v.15 no.4
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• pp.369-377
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• 1997

Purpose : This study was Performed to identify the histopathologic feature by the reevaluation of the Pathologic specimen of the cervical tumors and to evaluate the clinical findings and the treatment results of the patients with small cell carcinoma of the cervix treated by radiotherapy. Materials and Methods : 2890 patients with cervical carcinoma received radiotherapy at the Department of Radiation Oncology. Yonsei Cancer Center, Yonsei University College of Medicine between October 1981 and April 1995. Of the 2890 patients in this data base, sixty were found to have small cell carcinomas $(2.08\%)$. Among them thirty six patients were transferred from other hospitals. the biopsy specimens of those Patients were not available. So we could review the slides of the other twenty four patients who were diagnosed at our hospital. Twenty four patients with small cell carcinoma of the cervix were analyzed retrospectively based on the assessment of H & E staining and other four immunohistochemical stains for neuroendocrine differentiation (neuron specific enolase, chromogranin. synaptophysin and Grimelius stain). And we also evaluate the Patients and tumor characteristics. response to radiation. patterns of failures, 5 year overall and disease free survival rates. Results : Thirteen tumors were neuroendocrine carcinomas(13/24 = $54.2\%$) and eleven tumors were squamous carcinomas, small cell type (11/24 = $47.8\%$) based on the assessment of H & E staining and other four neuroendocrine marker studies. So we classified the Patients two groups as neuroendocrine carcinoma and small cell type of squamous carcinoma, Among the 13 neuroendocrine carcinomas, five were well to moderately differentiated tumors and the other eight were Poorly differentiated or undifferentiated ones. The median age was 54 years old (range 23-79 years). Eight Patients had FIGO stage IB disease, 12 had stage 11, 3 had stage III and one had stage IV disease, Pelvic lymph node metastases were found in five Patients $(20.8\%)$. three of them were diagnosed by surgical histologic examination and the other two were diagnosed by CT scan. There was no difference between two histopathologic groups in terms of patients and tumor characteristics. response to radiation. 5 year overall and disease free survival rates. However the distant metastases rate was higher in neuroendocrine carcinoma Patients (6/13:$46.2\%$) than in small cell type of squamous carcinoma Patients (2/11:$18.2\%$), but there was no statistically significant difference because of the small number of patients (P>0.05). Conclusion : More than half of the small cell carcinoma of the cervix patients were neuroendocrine carcinoma (13/24 : $54.1\%$) by reevaluation of the biopsy specimen of the cervical tumors. The tendency of distant metastases of the neurolndocrine carcinoma was greater than those of the small cell type of squamous carcinoma $(46.2\%\;vs.\;18.2\%)$. But there were no differences in the patients and tumor characteristics and other clinical treatment results in both groups. These data suggest that radical local treatment such as radiotherapy or radical surgery combined with combination systemic cytotoxic chemotherapy might provide these patients with the best chance for cure.

• Journal of Gastric Cancer
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• v.7 no.2
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• pp.74-81
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• 2007

Purpose: Routine pancreatico-splenectomy with total gastrectomy should no longer be considered as the standard surgical procedure for gastric cancer because of the lack of proven surgical benefit for survival. The aim of this study is to evaluate the clinicopathologic factors and the survival of patients with locally advanced gastric cancer and they had undergone combined pancreatico-splenectomy with a curative intent. Material and Methods: We retrospectively reviewed a total of 118 patients who had undergone total gastrectomy with distal pancreatico-splenectomy from 1990 to 2001. The patients were divided into 2 groups: 90 patients who were free from cancer invasion (group I), and 28 patients with histologically proven cancer invasion into the pancreas (group II). The various clinicopathologic factors that were presumed to influence survival and the survival rates were analyzed. Results: The rate of pathological pancreatic invasion was 23.7%. The tumor stage, depth of invasion, pancreas invasion, lymph node metastasis, lymph node ratio, curability and the hepatic and peritoneal metastasis were statistically significance on univariate analysis. Among these factors, the tumor stage, lymph node ratio and curability were found to be independent prognostic factor on multivariate analysis. The 5-years survival rates were 36.2% for group I and 13.9% for group II. The morbidity rate was 22.1%, and this included pancreatic fistula (5.1%), intra-abdominal abscess (4.2%) and bleeding (4.2%). The overall mortality rate was 0.8%. Conclusion: Combined distal pancreatico-splenectomy with total gastrectomy with a curative intent was selectively indicated for those patients with visible tumor invasion to the pancreas, a difficult complete lymph node dissection around the distal pancreas and spleen, and no evidence of liver metastasis or peritoneal dissemination.

• 전기의세계
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• v.38 no.6
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• pp.58-64
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• 1989

본고에서는 고속철도중 전기철도에 촛점을 맞춰 고속전철의 일반적 제어방식에 대해 논하고 또한 세계의 고속전철중 대표적 예인 프랑스의 TGV, 일본의 신간선, 서독의 ICE의 주회로에 대해 소개하기로 하고 특히 실제로 영업운행중인 TGV와 신간선의 가감속특성과 집전방식에 대하여 비교하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2010.10a
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• pp.134-136
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• 2010

예선은 일반적인 선박에 비해 협소한 선교를 가지고 있으며, 부선의 상태/상황 및 감시를 하기 위해 후방을 주시해야 한다. 이러한 예선의 특성을 시뮬레이션 시스템에 반영하기 위해서는 여러 고려사항이 있다. 협소한 선교를 가진다는 점은 현재 한국해양 연구원 해양시스템안전연구소가 보유하고 있는 CDS(Collimated Dome Simulator)의 조종실을 사용함으로써 반영할 수 있다. 하지만, 이 시스템은 전방에 대한 가시화만을 지원하며, 후방 가시화를 위해서는 360도 디스플레이 방식을 사용하는 것이 최적이다. 본 논문에서는 현재 보유 중인 CDS에 예부선 시뮬레이션 가시화의 특성을 반영할 수 있는 후방 가시화에 대한 개발 방안에 대해 다루고자 한다. 추가적인 장비를 조종실(선교)의 뒤쪽에 설치함으로써 CDS가 가지는 단점을 해결할 수 있을 것으로 예상된다.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1401-1406
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• 2004

In this paper, we present the theoretical and numerical results of scavenge characteristics in a small prechamber of an HCCI(Homogeneous Charge Compression Ignition) engine. Two theoretical models are proposed in prediction of the scavenge time and the efficiency ; one is the non-mixing models in which it is assumed that the input gas($CH_{4}$) and the existing gas(air) do not mix with each other, and the other is the fully-mixed model in which the two gases are assumed to mix completely before ejecting to the ambient air. Focus is also given to the effect on the scavenge performance of the size of the chamber oulet.

• 한국연소학회:학술대회논문집
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• 2001.06a
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• pp.187-192
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• 2001

A homogeneous premixed charge compression ignition engine is experimentally investigated for the reduction of exhaust emissions in diesel engines. In this study, the premixed fuel is injected into the intake manifold to form homogeneous pre-mixture in the combustion chamber and then this pre-mixture is ignited by small amount of diesel fuel directly injected into the cylinder. In the premixed charge compression ignition engine, NOx and smoke concentration of the exhaust emissions were reduced simultaneously as compared with the conventional diesel engine. But HC and CO emissions were increased with the increase of premixed ratio. The combustion characteristics of premixed charged diesel engine such as the power output, the rate of heat release, and the other characteristics are discussed.

• The Journal of the Acoustical Society of Korea
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• v.38 no.2
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• pp.200-206
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• 2019

In this paper, the characteristics of receiving voltage sensitivity about acoustic package in towed array sonar is analyzed through the numerical simulation and design of experiments. Simulation results show that the variation of receiving voltage sensitivity is caused by the structural resonance mode shape on baseline acoustic package. The effect of design parameters of the acoustic package are analyzed through the design of experiments to reduce the deviation of receiving voltage sensitivity. A change of hydrophone shield can thickness (t) is the greatest effect on the deviation of receiving voltage sensitivity. As a result of water tank test, the acoustic package derived from the design of experiments has reduced deviation of receiving voltage sensitivity.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.1
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• pp.49-54
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• 2003

The purpose of this work is to investigate the effect of premixed fuel on the reduction of exhaust emissions in premixed charge compression ignition engine. The premixed fuel is injected into the intake manifold to form homogeneous pre-mixture in the combustion chamber. The pre-mixture is ignited by a small amount of diesel fuel directly injected into the cylinder. In the case of gasoline as a premixed fuel of the engine, $NO_x$ and smoke concentration of exhaust emissions were reduced compared with the conventional diesel engine. But in the event of diesel fuel for premixed fuel, the rate of smoke reduction was small compared with the case of gasoline as a premixed fuel. HC and CO emissions were increased at high premixed ratio in the case of two premixed fuels. The combustion characteristics of the engine such as the combustion pressure, the rate of heat release, and other characteristics are compared.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.27-31
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• 2009

홍수피해를 예방할 수 있는 대책에는 여러 가지 방법이 있으나 비구조물적인 방법 중에서 대표적인 것이 홍수예경보이다. 이에 합리적인 설계홍수량 산정을 위해 하천유역에서 강우-유출과정의 정확한 해석과 유출예측은 수자원의 효율적인 활용과 하천의 이수, 치수를 위한 수문학적 해석에 있어서 매우 중요하며, 이를 위해서는 강우로부터 정도 높은 유출량 예측이 요구된다. 뿐만 아니라 하천범람 등의 재해로부터 인명과 재산을 보호하기 위한 홍수예경보 시스템의 구축이 필요하다. 홍수예경보 시스템의 효율적인 관리를 위해서는 실시간 홍수예측(Real-time Flood Prediction)기법의 개발이 필요하다. 홍수유출모형에 있어 공간적 변화특성과 평균 강우량의 공간분포를 반영할 수 있는 분포형 매개변수 모형(Distributed-Parameter Model)인 분포형 모델을 대상으로 앙상블 칼만필터(Ensemble Kalman Filter, EnKF) 이론을 적용하여 비선형시스템에서 오차를 포함한 반응을 실시간으로 처리하여 불확실성을 정량적으로 감소시켜 홍수유출을 예측하는데 그 목적이 있다. 하천유역특성을 이용한 홍수유출예측을 위하여 비선형시스템에서의 앙상블 칼만필터 기법을 적용한 분포형 모형을 이용하여 더욱 정밀한 홍수유출을 예측하게 되고 향후 홍수예경보모형으로서 적정 유역분할 규모를 결정해주는 근거를 제시할 수 있을 것으로 기대된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.347-347
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• 2021

국내 호우 및 태풍으로 인한 홍수피해는 전체 자연재해 피해액 중 90%에 달할 정도로 심각하다. 홍수 피해는 국내의 기후적 특성으로 인해 매년 반복될 뿐만 아니라 최근엔 기후변화로 인해 강우 패턴이 변함에 따라 홍수 대응에 대한 새로운 해결책이 요구되는 상황이다. 이러한 니즈에 맞춰 국내의 홍수 관리 기술 및 제도도 빠르게 발전해왔다. 기술적으로는 수문 관측 밀도, 자료의 축적, 전송, 분석기법 등이 상당한 수준에 이르고 있다. 다만, 단기 강우 예측, 고도화된 홍수해석모형, GIS와의 연계 등이 홍수 예경보 시스템과 실무에 직접적으로 활용되기 위해서는 아직 개발기술에 대한 실용화 연구 및 적용검증이 필요하다. 뿐만 아니라, 제도적으로도 「수자원의 조사·계획 및 관리에 관한 법률 및 시행규칙」을 통해 하천구역 및 그 배후지역에서 홍수로 인명과 재산에 대한 피해가 예상될 경우 홍수 예경보를 실시하도록 하고 있다. 그러나 최근 도달시간이 짧아 홍수선행예보시간이 확보되지 못하는 경우 등이 발생하며 홍수특보 기준에 대한 보완의 필요성이 제기되고 있다. 본 연구에서는 충분한 선행예보시간 확보 및 신속한 홍수대응을 위하여 홍수발생 및 예경보 발령 사례를 분석하고자 한다. 현재 홍수특보 발령 기준은 홍수위험정도에 따라 홍수주의보 또는 홍수경보로 구분하여 발령하도록 하고 있다. 홍수위험정도의 기준은 일반적으로 수위 또는 유량을 기준으로 하고 있으며, 이를 기준수위라고 정의하여 관리하고 있다. 본 연구에서는 홍수특보지점별 사례를 통해 지점의 지형적 특성, 기준수위, 기준수위에 도달시간을 종합적으로 분석하였다. 분석결과를 바탕으로 기존의 홍수특보를 효과적으로 운영하고 홍수피해를 저감하기 위해 고려해야 할 요소를 제시하였다.