SLALOM을 이용한 전광 직렬-병렬 데이터 형식 변환기

이성철,이기철,이석,박진우,Lee, Sung-Chul,Lee, Ki-Chul,Lee, Seok,Park, Jin-Woo 한국광학회 2002 한국광학회지 Vol.13 No.5

In this paper, we propose new simple schemes for all-optical serial-to-parallel and parallel-to-serial data format converters based on a semiconductor laser amplifier in a loop mirror (SLALOM) for all-optical data processing. They have the advantages of simple and easily expandable structure, efficient operation and easy implementation. We implement the proposed all-optical data converters. and experimentally demonstrate their operation. 본 논문에서는 SLALOM(Semiconductor Laser Amplifier in a Loop Mirror)을 사용하여 광신호를 직렬 데이터 형식에서 병렬 데이터 형식으로 또는 병렬 데이터 형식에서 직렬 데이터 형식으로 데이터 형식을 전광으로 변환할 수 있는 전광 직렬-병렬 데이터 형식 변환기의 구조가 제안되었다. 이 구조들은 간단하고 확장이 쉽고 효율적으로 동작하며 쉽게 구현될 수 있다. 제안된 데이터 형식 변환기를 구현하여 동작을 실험적으로 입증하였다.

네트워크 관리 - NMS만으로는 부족하다

이성철,Lee, Seong-Cheol 한국데이터베이스진흥원 1997 디지털콘텐츠 Vol.8 No.-

네트워크 관리자들은 흔히 네트워크 관리 시스템(NMS)에 모든 것들을 의지해 버리는 특성을 지니고 있다. 장애분석과 성능분석, 보안성 제공 등을 간단히 해결해주기 때문이다. 하지만 이것은 위험천만한 일이다. 그것은 현재 대부분의 NMS가 트래픽 분석 방법론을 제시해 주지 않을 뿐더러 분석이나 해결책 보다는 자료제공의 성격을 많이 띠고 있기 때문이다. 따라서 현재의 NMS로는 네트워크를 총체적으로 관리하기에 부족한 점이 없지 않다. 기존 NMS의 단점을 보완하고 있는 트래픽 분석 시스템을 들여다 보자.

설계인자 보정방법에 의한 사출성형기어의 캐비티 설계

이성철,김충현,권오관,허용정,Lee, Sung-Chul,Kim, Choong-Hyun,Kwon, Oh-Kwan,Huh, Yong-Jeong 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.10

As plastics shrink when changing from a molten to a solid state, mold cavities must by made larger than the product specification, In making molded gears, the teeth in the cavity must be carefully compensated for shrinkage so that the teeth of gears will have the correct profile. Two compensation methods are widely used in the cavity design. One is the compensation of a module and the other is the modification of a pressure angle and profile shifting coefficient. These methods, however, do not provide a gear cavity with all disign parameters for gears and several parameters are determined by experience. In this paper, the new design technique, namely the compensation method of design parameters, was proposed , which is based on the three kinds of shrinkage rates obtained from the measuring data of the prototype of molded gears. Using the shrinkage rates in the tip circle, tooth heigth and tooth thickness, we calculate the whole design parameters of a gear cavity. Thus, the gear cavity is considered as a complete gear with the compensated module, pressure angle, profile shifting coefficient, clearance coefficient and back lash amount so that the formula of gears can be applied to the cavity design effectively. Experimental results show that more precision molded gears can be made by using the proposed design method.

담도 폐쇄증에서 광범위 간문부 절제 및 간문부-공장 문합술의 치료성적

이성철,Lee, Seong-Cheol 대한소아외과학회 1997 소아외과 Vol.3 No.2

Extended porta hepatis dissection and hepatic portojejunostomy was performed on 14 biliary atresia patients during last 13 years by a single surgeon. The average age at operation was 68 days(range from 37 days to 98 days). The patients were admitted for 8 weeks postoperatively for administration of parenteral antibiotics. There was one operative mortality due to acute hepatic necrosis. Among 13 patients remaining, 12(92.5 %) became chemically jaundice-free within 36 weeks postoperatively(average 16.8 weeks). the earliest 8 weeks, and in one patients jaundice persisted. Five(38.5 %) patients developed cholangitis after operation. Among jaundice-free patients, one patient died of unrelated disease 2 years after hepatic portojejunostomy, who underwent left lateral segmentectomy because of a biloma. Eleven survivors(78.6 %) are jaundice-free. The oldest one is 13 years old, enjoying a normal life. The mean period of follow-up is 7 years and 3 months.

FBG 센서를 이용한 강연선 전달길이 측정

이성철,최송이,신경준,김재민,이환우,Lee, Seong-Cheol,Choi, Song-Yi,Shin, Kyung-Joon,Kim, Jae-Min,Lee, Hwan-Woo 한국전산구조공학회 2015 한국전산구조공학회논문집 Vol.28 No.6

In this paper, an experimental program has been conducted to investigate transfer length in high strength concrete members pretensioned through a seven-wire strand with FBG sensors. To measure transfer length, five members were fabricated, which had a length of 3 m and a cross-section of $150{\times}150mm$. It was measured that the concrete compressive strength was 58MPa at pretensioning. Test results indicated that more precise and reliable measurement on the transfer length was attained with FBG sensors than conventional gauges attached on concrete surface. Through comparing the measured transfer length and predictions, applicability of several transfer length models in literature was investigated. This paper can be useful for relevant research field such as investigation on the bond mechanism of a seven-wire strand in concrete members. 본 논문에서는 프리텐션된 고강도 콘크리트 부재에서의 전달길이를 측정하기 위해 FBG 센서가 기입된 스마트 강연선을 활용하여 실험을 수행하였다. 전달길이 측정을 위해 길이 3m, 단면 $150{\times}150mm$의 고강도 콘크리트 시험체를 총 5개 제작하였으며, 프리텐션 도입 시 콘크리트 압축강도는 58MPa로 측정되었다. 실험 결과 콘크리트 표면에 부착하는 기존의 전기 저항식 게이지보다 FBG 센서로부터 보다 정밀하고 신뢰성있는 강연선의 전달길이를 계측할 수 있는 것으로 나타났다. 계측결과로부터 산정된 강연선 전달길이를 기존의 여러 모델들과 비교하였으며, 이를 통해 고강도 콘크리트 부재에서의 전달길이 산정에 대한 기존 모델들의 적용성을 분석하였다. 본 연구 내용은 향후 강연선의 부착 특성 분석 등의 관련 분야 연구 등에 유용할 것으로 기대된다.

냉간 압축 하에서 금속 분말의 치밀화 거동

이성철,김기태,Lee, Seong-Cheol,Kim, Gi-Tae 대한기계학회 2002 大韓機械學會論文集A Vol.26 No.1

Densification behavior of aluminum alloy(A16061) powder was investigated under cold compaction. Experimental data were obtained under triaxial compression with various loading conditions. A special form of the Cap model was proposed from experimental data of A16061 powder under triaxial compression. The proposed yield function and several yield functions in the literature were implemented into a finite element program (ABAQUS) to compare with experimental data for densifcation behavior of A16061 powder under cold isostatic pressing and die compaction. The agreement between finite element calculations from the proposed yield function and experimental data is very good under cold isostatic pressing and die compaction.

유관 압박나사를 이용한 거골하 관절유합술

이성철,정홍근,전지용,유제욱,Lee, Sung-Chul,Jung, Hong-Geun,Chun, Ji-Yong,Yu, Je-Wook 대한족부족관절학회 2005 대한족부족관절학회지 Vol.9 No.1

Purpose: To analyze the overall clinical outcome, overall assessment, and patient's satisfaction rate of subtalar arthrodesis using the cannulated compression screw. Materials and Methods: This study is based on 17 patients, 17 feet who underwent subtalar arthrodesis using the cannulated compression screw from March, 1997 to March, 2004 with at least 1 year follow-up. The average follow-up period was 33.0 months (12 to 72 months). Functional results were assessed using the American Orthopaedic Foot and Ankle Society Ankle-Hindfoot (AOFAS) score, and Visual Analysis Scale (VAS) pain score, patients' returning to previous occupation and patients' satisfaction rate were also evaluated. Results: The mean AOFAS scores at final follow-up were 80.4 points (range $66{\sim}92$). The satisfactory rates were as follow. Thirteen patients (76.4%) were at least satisfied with surgical result at final follow-up. Patients' VAS pain score was average 2.8 points ($1{\sim}6$). Fourteen (82.3%) patients returned to previous job at mean postoperative period of 11.3 months (range 3-18 months). Patients' work efficiency after returning to previous occupation was 68.7% (range $33{\sim}100%$). There were 9 complications which were 3 cases of sural nerve injury, 1 case of valgus malunion, and 5 cases of the hindfoot residual pain. Conclusion: We obtained the satisfactory functional results with relatively high patient satisfaction rate of 76%. So we conclude that subtalar arthrodesis using the cannulated compression screw is a reliable method for addressing the painful end-stage subtalar osteoarthritis and unreconstructible comminuted calcaneal fractures. However we also found out that average 11 months were necessary for patients to return to their job.

Allergic Purpura에 합병된 Acute Pancreatitis 1례

이성철,김화자,차한,박호진,Lee, Sung-Chul,Kim, Hwa-Ja,Tchah, Hann,Park, Ho-Jin 대한소아소화기영양학회 1999 Pediatric gastroenterology, hepatology & nutrition Vol.2 No.1

저자들은 복통, 구토, 혈변을 주소로 입원한 6세 여아에서 allergic purpura에 급성 췌장염이 병발된 1례를 경험하였기에 문헌고찰과 함께 보고하는 바이다. Allergic (Henoch-Schonlein) purpura is a nonthrombocytopenic purpura that affects small nonmuscular vessels with involvement of skin, gastrointestinal tract, joint, and kidney. Pancreatitis has rarely been reported as a complication of H-S purpura. In 1965, hemorrhagic pancreatitis as a complication of H-S purpura was reported by Toskin. We experienced one case of pancreatitis complicated with H-S purpura: pancreatic head enlargement was noted in small bowel series and abdominal sonogram with increased serum amylase level (160 U/dL) in a 6-year-old female child who complained of abdominal pain, vomiting, bloody stool, and petechiae on lower extremities.

번식-이유후 3-5일 된 모돈의 1회 교배

이성철,Lee, Seong-Cheol 대한양돈협회 1994 養豚 Vol.16 No.3

소아의 이소성 경부흉선 1예

이성철,양석진,김우기,Lee, Seong-Cheol,Yang, Seok-Jin,Kim, Woo-Ki 대한소아외과학회 1996 소아외과 Vol.2 No.1

Aberrant migration of thymic tissue occurs as an ectopic thymus in the mediastinum, base of skull, tracheal bifurcation, and cervical region. A recent review of the literature by Nowak et al. showed over 70 reported cases of aberrant thymus or thymic cyst in patients who presented with primary neck masses. Authors experienced a case of ectopic cervical thymus and reviewed the literature. A one-year-old boy with left neck swelling which had been noticed since one month of age visited out patient clinic. Ultrasonography showed a well-defined cystic mass containing homogeneous, low-echogenic content locating in the lateral aspect of the left carotid sheath. Operation was performed under the impression of branchial cleft cyst. At surgery, a multiseptated, well-encapsulated, brownish and doughy mass which was extending into the vicinity of the carotid bifurcation with sland stalk-like portion ending between the hypoglossal nerve and external carotid artery was excised completely. The cut-surface showed homogenous solid mass, and on frozen section the tissue revealed a normal thymic histology. Postoperative ultrasonography showed bilateral thymus in the superior mediastinum. The patient has no immunologic problem and is doing well now. 1세된 남아에서 세열낭종을 의심한 좌측 경부 종양이 수술을 시행한 결과 고형종양이였고, 조직검사상 이소성 흉선으로 판명되었다. 술후 초음파상 흉선은 정상적으로 있었고, 현재 환자의 면역기능은 아무 이상없이 정상으로 자라고 있다.