Moment法에 依한 一定電位인 任意 直線導體의 電荷分布의 解析

吳承燁 충남대학교 공업교육연구소 1979 論文集 Vol.2 No.1

Moment method has recently been introduced as one of the most important methods for the solution of electromagnetic field problems. This approach is conceptually simple and easily usable by the practicing engineers. The moment method is founded in the theory of linear vector spaces. On this paper, the arbitary thin wire which holds a constant potential is divided into N-segments each of which is considered to have its charge density. And then numerical methods of integral for potential are applied and the charge density of each segments is determined.

저잡음 Feedforward 초고주파 증폭기를 위한 온도안정 지연선로의 설계

吳承燁 忠南大學校 産業技術硏究所 1986 산업기술연구논문집 Vol.1 No.2

This paper presents the design on MIC delay lines on the (ZrSn) ceramic substrate which has characteristics of high dielectric constant and stable temperature coefficient. This type of delay lines will meet the requirements of the time delay elements in the MMIC feed-forward M/W LNAs. The procedures of the design take frequency dispersion and loss of the microstrip lines into account, and also the effect of the temperature expansion coefficient is compensated by minus temperature coefficient of dielectric constant. The results of experiment show that the error of delay time of the delay line is about 1.25% in the range of 9-10GHz and temperature stability is very good (±0.5ppm/℃)

업무특성과 전자결재시스템 활용간의 관계 : 매체 풍부성 이론 관점

오승엽,김영걸 한국경영정보학회 1998 한국경영정보학회 학술대회논문집 Vol.1998 No.-

雙円錐形 안테나를 利用한 미리波·써브 미리波帶의 檢出回路素子

吳承燁,小野昭一 충남대학교 공업교육연구소 1982 論文集 Vol.5 No.2

In this paper, we discuss the biconical antenna with spherical reflector to use it as a milliand submilli-meter wave detection device with Schottky diode. First, this structure is experimented as an oscillator device at X-band frequency with Gunn diode and at 80 GHz frequency with Impatt diode to find its characterics as a resonator. Second, the structure is tested as a receiving device with Schottky diode at X-band and Infrared-Band to find its characteristics as an antenna. Our experiments show that: 2) This structure is convenient for impedance matching with solid-state elements. 2) Resonant frequencies of the structure are changed by a moving spherical reflector, but its range is narrow. 3) As an antenna, its directivity is good and then this antenna is a proper one to receive the sub-millimeter wave laser whose beam is a spherical Gaussian form.

폐색성 좌측 대장암에서 Stent 삽입의 종양학적 안정성

오승엽,이광재,김진홍,서광욱,박승현 대한대장항문학회 2007 Annals of Coloproctolgy Vol.23 No.3

Purpose: There is a controversy about the treatment of left-sided obstructive colorectal cancer. Recently, experience using an expandable metallic stent for relief of the obstruction has been increasing, but its oncological safety has not been confirmed. Therefore, we designed this study to evaluate the oncological safety of a metallic stent for the treatment of left-sided obstructive colorectal cancer. Methods: Forty-six patients with left-sided obstructive colorectal cancer who underwent a curative resection from 1994 to 2004, were retrospectively evaluated. Nineteen emergency operations (1994~2003) and 27 metallic stent insertions (2000~2004) were compared based on clinicopathologic features, postoperative complications, recurrence rates, and survival rates. Results: There were no significant differences in age, location, sex, and recurrence rate between the two groups. The complication rate in the emergency group was higher than it was in the stent group, but this difference was not statistically significant (26.3% vs. 14.8%; P=0.33). The overall and the disease-free survival rates were not significantly different. Conclusions: Because there was no significant differences in survival rate and recurrence rate between the two groups, metallic stent insertion can be used safely in the preoperative treatment of obstructive left-sided colorectal cancer.

복회음절제술을 시행한 하부직장암의 종양학적 결과

오승엽,이호원,서광욱 대한대장항문학회 2006 Annals of Coloproctolgy Vol.22 No.6

Purpose: Literature shows that low rectal cancer, that especially undergoing abdominoperineal resection (APR), is worse than mid or high rectal cancer. Two reasons have been proposed: diverse lymphatic channels in the low rectum, and technical difficulty in performing the APR. By comparison with the results reported in representative literature, we tried to find out whether low rectal cancer is really worse oncologically than high rectal cancer. Methods: For 133 patients who underwent an APR from 1995 to 2005, we examined the pathological characteristics of the cancer, the recurrence, the metastasis, the survival rates, and the prognostic factors. Results: The patient distribution according to stage was 15.9% in stage I, 33.6% in stage II, and 50.4% in stage III. The overall 5-year actuarial survival rate (5SR) of patients undergoing a curative resection (n=113) was 74.6%. Local pelvic recurrence was found in 11.5% of the patiennts, and systemic metastasis was noted in 14.2%. Among several prognostic variables, lymph node metastasis, the number of metastatic lymph nodes, adjuvant chemotherapy, and the distance between the tumor border and the dentate line were significant factors. In the multivariate analysis, lymph node metastasis was the most significant prognostic factor. Conclusions: It is true that a curative resection in low rectal cancer is difficult due to the anatomy of pelvis, so knowledge of the anatomic features of the pelvis and surgical skill are important. definitely, acceptable oncological results can be attamed if the rule of curative resection is obeyed. We also found that lymph node involvement was the most significant prognostic factor in low rectal cancer.

직장 기형종 1예

오승엽,송선춘,이광재,김영배,서광욱 대한대장항문학회 2007 Annals of Coloproctolgy Vol.23 No.2

We report the case of a rectal teratoma. A 62-year-old woman was referred to our department for evaluation of a rectal mass. She had a 3-month history of rectal bleeding and constipation. No palpable mass was detected using digital rectal examination. Colonoscopic examination demonstrated a protruding mass with a broad stalk in the posterior wall about 12 cm from the anal verge. A computed tomography scan showed a mass, which contained calcifications and fatty components, protruding into the rectal lumen. On operation, the mass was located in the upper rectum, and the right lateral portion of the upper rectum was adhesed to the right ovary. Thus, she had undergone a low anterior resection and right oophorectomy. The pathologic results confirmed a teratoma arising in the muscularis mucosa and the submucosa of the rectal wall.

국소진행성 직장암에서 Irinotecan을 이용한 술전보강화학방사선치료 시 UGT1A1 유전자 다형태의 유용성

오승엽,김영배,전미선,서광욱 대한대장항문학회 2007 Annals of Coloproctolgy Vol.23 No.5

Purpose: Irinotecan (CPT-11) is hydrolyzed to an active SN-38, which is further detoxicated to SN-38G through conjugation by uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) enzymes. There are many reports that UGT1A1 polymorphisms are associated with irinotecan related dose-limiting toxicity. The aim of the present study is to determine whether UGT1A1 polymorphisms affect individual variations of the toxicity due to and the tumor response to irinotecan via the alteration of bioavailability of SN-38 in Korean patients with locally advanced rectal cancer. Methods: Twenty patients with locally advanced rectal cancer, who had received surgery after irinotecan- containing chemoradiation from 2003 to 2006, were enrolled. We analyzed the association of UGT1A1 genotypes with toxicity and tumor response to chemoradiation therapy. A tumor response was assumed when a tumor regression grade I or II was obtained. Toxicity was graded in accordance with the NCI common toxicity criteria. Results: The frequence of -53(TA)6>7 (UGT1A1*28), 211G>A (UGT1A1*6), 686C>A (UGT1A1*27), -3279T>G (UGT1A1*60), and -3156G>A were 25% (5/20), 25% (5/20), 0% (0/20), 55% (11/20), and 20% (4/20), respectively. There were five grade III neutropenia and one severe diarrhea. Patients with UGT1A1*28 and -3156G>A showed higher complete tumor response rates (40% vs. 6.7%, P=0.07; 50% vs. 6.3%, P=0.08), but there was no differences in toxicity and tumor response between responders and non-responders. Patients with -3279T>G (UGT1A1*60) showed a tendency for lower tumor response in tumor responders, but there was no statistically significant difference (P=0.07). Conclusions: This study suggested that -3279T>G (UGT1A1*60) may be useful in predicting tumor response of irinotecan. In the future, further study is warranted using large numbers of cases to reach statistical significance.

전립선용적과 하부요로증상이 발기능에 미치는 영향

오승엽,민권식,최성협 대한비뇨의학회 2007 Investigative and Clinical Urology Vol.48 No.1

위성방송 시대를 대비한 남북 TV 방송 방식 통합에 관한 연구

오승엽 한국통신학회 1992 한국통신학회 전기통신학술연구과제 Vol.- No.-