고등급 이형성을 보인 편평톱니샘종

권경주,정성애,심기남,정정화,강석형,송도경,전승정,김혜인 이화여자대학교 의과학연구소 2012 EMJ (Ewha medical journal) Vol.35 No.1

Until recently, colorectal polyps were classified predominantly as hyperplastic or adenomatous. While adenomatous polyps are well-characterized precursor lesions of adenocarcinomas, hyperplastic polyps have been considered as benign lesion. However, some hyperplastic polyps with serrated morphology of the crypts have been recognized to have distinctive features and these polyps were termed ‘serrated adenomas’. Recent data show that sessile serrated adenomas (SSA) might be the precursors of serrated colonic cancers, underlining the necessity of identifying them. SSA is approximately 3% of all polyps, commonly appears as flat or sessile and yellowish due to mucus production. In the pathogenesis of SSA, progression to high grade dysplasia or early invasive carcinoma may be associated with serrated neoplasia pathway different from adenoma-carcinoma sequence. We report a case with a colon polyp diagnosed as sessile serrated adenoma with high grade dysplasia after endoscopic submucosal dissection.

한국인 관상동맥의 변화양상에 대한 형태학적 연구

권태정,이상용,이한영,고영창,권기석,조재홍,김태공,김유훈,조갑래,서중석,이원태 內務部 國立科學搜査硏究所 2001 國立 科學 搜査 硏究所 年報 Vol.33 No.-

스테인레스강 절삭가공에서 공구의 온도 특성에 대한 실험적 연구

권용기,오석형,김동현 한국공작기계학회 1996 한국생산제조학회지 Vol.5 No.1

This is an experimental investigation of the temperature generated in a cutting tool during the machining of stainless steel. The temperature results from the wear of the cutting tool are considered in order to investigate the relation between cause and effect of these factors. This possibility has been tested using a thermocouple technique to record temperature vs. time curves for a variety of cutting conditions. This is done by employing a thermocouple inserted on the tool tip near the major cutting edge. Temperature distributions are calculated using finite element method and compared to the contour maps measured by an optical system. It suggests that the temperature gradients and the tool performance will be dependent on certain factors in tool geometry when cutting this material.

Tabes Dorsalis의 핵자기공명영상 및 전기생리학적 소견

권기한,김성민,권석범,이병철,조광호,주정희 대한신경과학회 1999 대한신경과학회지 Vol.17 No.3

대두 및 대두발효식품의 항돌연변이성

윤기도,권동진,홍석산,김수일,정건섭 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.4

To investigate the inhibitory effect of soybean and Korean traditional fermented soybean products on the chemically induced mutagenesis, we extracted soybean, Kanjang, Doenjang, Kochujang, and Chonkukjang with water, methanol and hexane. Inhibitory effect of extracts was assayed by the SOS chromotest using Escherichia coli PQ37 as a test strain. 4-nitroquinoline-1-oxide(4NQO), N-methyl-N'-nitro-N-nitrosoguanidine(MNNG), and aflatoxin B_1(AFB_1) were used as mutagens. Methanol extracts showed relatively higher inhibitory effect than water and hexane extracts. Methanol extracts of soybea, Doenjang, Kochujang, and Chongkukjang showed inhibitory effect of 68.4, 96.3, 17.5, and 100.9%, against MNNG, and 28.6, 109.1, 41.3, and 101.8% against AFB_1., respectively. Doenjang methanol extract showed inhibitory effect of 51.0, 96.3, and 109.1% against 4NQO, MNNG, and AFB_1. Inhibitory effect of heat-treated Doenjang and Chongkukjang methanol extracts on the mutagenicity of MNNG and AFB_1 was remained over 95% of the inhibitory effect of heat-untreated extracts, demonstrating the heat stability of the potent antimutagenic activity.

시간-주파수 해석법에 의한 CFRP의 파괴 거동

남기우,안석환,이상기,김현수,문창권 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.1

신호처리법으로 현재 많이 사용되고 있는 푸리에 변환은 신호의 주파수 성분이 사간에 따라 어떻게 변화하는지를 표현하지 못한다. 따라서 최근 이와 같은 푸리에 변환의 단점을 보완하여, 신호의 시간과 주파수에 대한 정보를 동시에 표현할 수 있는 시간-주파수 해석법들이 개발되었다. 본 연구에서는 음향방출을 이용하여 복합재료의 주요 발생원으로 알려져 있는 기지균열, 섬유분리, 섬유파괴 및 층간분리 등과 같은 파괴기구를 해석하였다. 각각의 파괴특성이 나타나도록 시험편을 제작하여 인장시험 시 검출된 음향방출신호의 시간-주파수 해석을 통해 전체 파괴기구의 특징을 분석하였다. Fourier transform has been one of the most common tools to study the frequency characteristics of signals. With the Fourier transform alone, however, it is difficult to tell whether signal's frequency contents evolve in time or not. Except for a few special cases, the frequency contents of most signals encountered in the real world change with time. Time-frequency analysis methods are developed recently to overcome the drawbacks of Fourier transform, which can represent the information of signals in time and frequency at the same time. In this study, damage process of cross-ply carbon fiber reinforced plastic (CFRP) under monotonic tensile loading was characterized by acoustic emission. Different kinds of CFRP specimens were used to determine the characteristics of AE signals. Time-frequency analysis methods were employed for the analysis of fracture mechanisms in CFRP such as matrix cracking, debonding, fiber fracture and delamination.

Developpe devant 수행시 하지 관절 모멘트 분석

박기자,신성휴,권문석,김태완,이형나 한국운동역학회 2004 한국운동역학회지 Vol.14 No.1

K. J. PARK, S. H. SHIN, M. S. KWON, T. H. KIM, H. N. LEE. Analysis on lower extremity joint moment during a developpe devant. Korean Journal of Sport Biomechanics, Vol. 14, No. 1, pp. 133-144, 2004. The purpose of this study was to analyze the joint moment on lower extremity during a developpe devant. Data were collected by Kwon3D, KwonGRF program. Two professional modem female dancers were participated in this experiment. Subjects performed a developpe devant in meddle heights. On the axes of X, Y, Z, it was shown that the maximum joint moment was occurred in hip joint. The moments are plotted during developpe devant. The ankle muscles generate a plantar flexion moment and the knee muscles generate a flexion moment and The hip muscles generate a extension moment. So these muscles of joint muscles were known to play a key role in keeping the body balance while doing developpe devant. In addition adduction moment occurred at hip, knee, an ankle in the order of amount, we could assume from this data that turn out motion started from the hip joint. There was small active turn out possible below the hip joint. A small amount of extra turn out could be obtained when standing because of flexion between the foot and floor, which could be used to give a passive external rotation force to the whole leg and this could produce a rotation between the knee and foot. This passive external rotation could produce very damaging results. Therefore, lower extremity joint muscles such as hip, knee, and ankle muscle should be trained to keep the body balance and prevent injury during developpe devant performance. And for the safe and perfect turn ort performance, hip joint abduction, the most important external rotating muscle for turn out is needed to train and full stretching should be done in advance.

Developpe devant 수행시 지향각(Orientation angles)을 이용한 골반과 하지의 신체정렬

박기자,권문석,이경화 한국스포츠리서치 2003 한국 스포츠 리서치 Vol.14 No.6

The purpose of this study was to persnet proper alignment of pelvis and lower extremity using orientation angles during a developpe devant. Data were collected by Kwon3D program. Two females professional modern dancer were participated in this experiment. Subjects performed a developpe devant in meddle heights(about 90 deg.) The results were as follows: First, in axes of X, pelvis, left thigh, left shank were aligned from 0° to 3° and left foot was aligned from 92° to 94°. Second, in axes of Y, pelvis(-ll°~-8°), left thigh(-6°~-2°), left shank(5°~8°), left foot(12°~18) were aligned. Third, in axes of Z, pelvis(5°~10°), left thigh(-20°~-15°), left shank(27°~32°), left foot(7°~10) were aligned.

馬山灣에서의 燐과 窒素의 動態에 관하여

안태석,안태영,권오섭,조기성 江原大學校 附設 環境硏究所 1989 環境硏究 Vol.6 No.-

1978년 부터 1982년 까지 마산만 4개 정점에서 인산에 인과 질소 상태에 대한 조사 결과, 인산태 인과 질소 상태에 대한 조사 결과, 인산태 인은 각 정점별 평균치가 0.86∼2.70 μg at - P/ℓ이였고, Ammonia + amino 산태 질소는 1.21 ∼4.36 μg at - L/ℓ이였고, 질산태 질소는 0.94 ∼ μg at - N/ℓ 로 비교적 높은 값을 보였다. 마산시에 인접한 정점 1, 2에서는 질소의 농도가 점차로 증가하고 있는 경향을 보였다. 또한 질소와 인의 비율은 정점 1과 2에서 40을 넘는 값을 보여주어, 질소의 유입이 큰 것을 뜻하므로 이에대한 방지대책이 시급히 요구된다. The concentrations of phosphate-P, ammonia + amino acid-N, nitrite-N, and nitrate-N were measured at 4 sites in the polluted Masan Bay from 1978 to 1982. The mean concentration of phosphate-P, ammonia + amino acid-N, nitrine-N and nitrate-N in each site varied 0.68-1.90 ug at P/1, 1.21-4.36 ug at-N/1, 0.36-3.23 ug at-N/1 and 2.17-29.45 ug at-N/1, respectively. At site 1 and 2, nearyby Masan City, the concentration of nitrogen was gradually increasing according to the increase of the population of the city and the N/P ratios at site 1 and 2 reached more than 40.

LED의 구조가 전류 퍼짐에 미치는 영향

최기석,권기영 공주대학교 생산기술연구소 2001 論文集 Vol.9 No.-

In this paper, we have studied on the effect of structural parameters on current spreading in LED's