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.

유한요소법에 의한 박판곡선부채의 좌굴해석

이성철,Lee, Sung Chul 대한토목학회 1991 대한토목학회논문집 Vol.11 No.2

A computer program for the linear elastic buckling anlalysis of thin walled members is developed using a 3-node triangular shell element. The element has real stiffness value for a kinematic degree of freedom associated with rotation about the surface normal at each node. The validity of the present computer program is demonstrated through the plate buckling analysis and the lateral-torsional buckling analysis of a straight beam. Then, simply supported circular arches subjected to uniform bending are analyzed and the results are compared with existing solutions. 평면내에서의 비틀림에 대한 강성도를 갖는 3절점 삼각형 shell요소를 사용하여 박판으로 이루어진 곡석 또는 직선부재의 선형 탄성좌굴 해석을 위한 컴퓨터 프로그램을 개발 하였다. 판의 좌굴 해석과 보의 횡 비틈 좌굴해석을 통하여 본 프로그램의 타당성을 입증하였고, 이를 순수 휨을 받는 양단의 단순지지된 원호 아치의 좌굴해석에 적용시켜 그 결과들을 다른 연구 결과들과 비교 검토하여 보았다.

저절로 파열된 횡경막 이완증 1예

이성철,김기홍,Lee, Seong-Cheol,Kim, Ki-Hong 대한소아외과학회 2000 소아외과 Vol.6 No.1

Spontaneous rupture of the eventrated diaphragm is not common. The authors report a case of spontaneous rupture of the congenital diaphragmatic eventration. An 8 year-old girl with right congenital diaphragmatic eventration and nephrotic syndrome was seen in emergency room because of severe abdominal pain and vomiting. She had intermittent abdominal pain for 1 year. Plain chest X-ray and ultrasonography showed entrapped bowels in the right thoracic area. Exploratory laparotomy revealed a ruptured right eventration. THE displaced abdominal viscera were repositioned into the abdominal cavity and the ruptured diaphragm was trimmed and plicated. The postoperative course was uneventful. Only one case of spontaneous rupture of eventrated diaphragmatic has been reported in the English literature.

영아 Bochdalek 탈장의 임상적 고찰

이성철,성숙환,Lee, Seong-Cheol,Seong, Suk-Hwan 대한흉부심장혈관외과학회 1987 Journal of Chest Surgery (J Chest Surg) Vol.20 No.4

Authors carried out a retrospective study in 22 infants with Bochdaleck`s hernia who were operated upon, the results are; 1] the male to female ratio was 2:1 and the incidence of left side was threefold prevalent than right, 2] the chief complaint of those who were operated upon in neonatal period was dyspnea and diagnosis was possible by chest A-P, 3] primary repair was possible except one patient in whom a prosthesis was used. 4] complication occurred in 41% and pulmonary complication was most common including 5 pneumothorax, 5] mortality rate was 14%, the deaths occurred in infants who were operated upon within 48 hours of life and the lesion was left without sac, the defect was larger than average and all died within 72 hours after operation.

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.

표준관입시험의 N값을 이용한 비배수전단강도 및 선행압밀응력의 추정

이성철,김지용,조성민,김태형,Lee, Sung-Cheol,Kim, Ji-Yong,Jo, Sung-Min,Kim, Tae-Hyung (사)한국토질및기초기술사회 2006 기술발표회 Vol.2006 No.-

This study researched N-Value, strength of clayey soil and preconsolidation pressure m order to variety application of standard Penetration test. We compared it makes on analysis of the relationship of the N-value and $q_u$ with relation formula is presented in existing, presented the estimated preconsolidation pressure by using the predicted undrained shear strength.

한국 Peutz-Jeghers 증후군의 특징

이성철,이현국,양석진,정성은,박귀원,김우기,Lee, Seong-Cheol,Lee, Hyeon-Kook,Yang, Suk-Jin,Jung, Sung-Eun,Park, Kwi-Won,Kim, Woo-Ki 대한소아외과학회 1997 소아외과 Vol.3 No.1

Eight pediatric patients with Peutz-Jeghers syndrome were treated from 1984 to 1994 at the Department of Surgery, Seoul National University Children's Hospital. We reviewed the clinical features of our own 8 cases as well as 56 cases reported in Korean literatures. The results were compared to those of western reports. Gastrointestinal complications in our series were more frequent than in the Korean series, but the distribution of polyps was similar. The Korean series showed the following characteristics compared to the western reports; demographic backgrounds were similar; gastrointestinal symptoms were more common; location of the polyp was more frequent in colon (2 times); and the most prevalent site of malignant change was the colon in Korean cases.

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.

뇌실복강간 단락술(Ventriculoperitoneal Shunt)을 시행한 환자에서의 서혜부 탈장의 빈도와 특성

이성철,이혁준,김기홍,정성은,박귀원,김우기,Lee, Seong-Cheol,Lee, Hyuk-Joon,Kim, Ki-Hong,Chung, Sung-Eun,Park, Kwi-Won,Kim, Woo-Ki 대한소아외과학회 2000 소아외과 Vol.6 No.2

Ventriculoperitoneal shunt(VP shunt) for hydrocephalus is thought to inhibit the closure of processus vaginalis and promote inguinal hernia by increasing intraabdominal pressure. To estimate the patency rate of processus vaginalis and the incidence and characteristics of the inguinal hernia, 262 cases of VP shunt in early childhood between January 1980 and May 1998 at Seoul National University Children Hospital were reviewed retrospectively. Inguinal hernia developed in 28 cases(10.7 %), but six patients had an inguinal hernia before the VP shunt was placed. Patients who had a VP shunt before 6 months of age developed inguinal hernia in 16.2 %(12/74) of cases, patients shunted between 6 months and 2 years had an incidence of 12.4 %(11/89) and only 5.1 %(5/99) of patients operated upon after 2 years of age developed hernias. Twenty-two patients out of 256 cases (8.6 %) developed inguinal hernia after VP shunt, with male predominance(M : F=4.5:1). Eight patients developed inguinal hernia bilaterally(36.4 %). It is suggested that at least 14% of processus vaginalis is patent until 2 years old.

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.