성장호르몬 분비성 뇌하수체 선종에서 소마토스타틴 수용체 (제2아형, 제5아형), G_i2α 및 Pit-1 유전자 발현

류미숙,양인명,박철영,우정택,김성운,김진우,김영설,최영길,김은희,박승준,김국기 대한내분비학회 2002 Endocrinology and metabolism Vol.17 No.2

Background: Mutation of Gs protein subunit (gsp oncogene), detected in about 30∼40% of growth hormone (GH)-secreting pituitary tumors, is associated with an increased long-acting somatostatin analog octreotide sensitivity. However, the mRNA expression of somatostatin receptor (sst) was not changed in the GH-secreting pituitary tumor, regardless of whether they were gsp oncogene positive or negative. This suggests that the expression of genes coding for G_i2α, Pit-1 and the other factors involved in the regulation of secretory activity in somatotrophs is likely to be altered in gsp oncogene positive tumors. We observed the impact of the gsp oncogene on the expression of the genes coding for Gi2, Pit-1 and sst (2&5) in GH-secreting pituitary tumors. Methods: The GH response to octreotide was examined in 13 acromegalic patients before transsphenoidal adenomectomy. Genomic DNA and RNA were extracted from fresh frozen tumor tissues. PCR was performed to amplify and sequence the region between codon 184 and 251 that includes exons 8 and 9 of the Gs gene. Sst2, sst5, G_i2α and Pit-1 mRNA levels were measured by semi-quantitative RT-PCR. Results: Sst2 and sst5 mRNA transcripts were detected in all tumors (7 gsp +, 6 gsp-). The amount of sst transcripts varied considerably varied between the tumors. There were no significant differences in sex, age, tumor size, grade or basal GH levels. Pit-1 and sst2 mRNA levels were not different. In contrast, G_i2 mRNA levels were significantly higher in gsp (+) while sst5 mRNA levels were higher in gsp (-). Conclusion: These data suggests that gsp oncogene may increase Gi2α levels but decrease sst5 mRNA levels. However, Pit-1 and sst2 mRNA expression may not be affected by gsp oncogene. The increased expression of the G_i2α gene might be an inhibitory compensatory response to the action of gsp oncogene

아웃 블록을 찾기 위한 제약조건을 갖지 않는 상수시간 RMESH 알고리즘

우진운,김기원 단국대학교 1999 論文集 Vol.34 No.-

A linear quadtree representation as a way to store a quadtree is efficient to save space compared with other representations. It, therefore, has been widely studied to develop efficient algorithms to execute operations related with quadtrees. In this paper, we present an O(1) time algorithm without constraints for finding neighbor blocks of locational codes representing linear quadtrees, using three-dimensional n×n×n RMESH.

W치환 2205 이상 스테인리스강의 크리프 특성 평가에 관한 연구

김기엽,최병호,남기우,안용식 한국비파괴검사학회 2004 한국비파괴검사학회지 Vol.24 No.1

22Cr-5Ni 2상 스테인리스강의 합금원소 중 몰리브덴(Mo) 원소를 텅스텐(W)으로 치환하여 크리프거동에 미치는 영향을 조사하였다. 크리프시험은 600℃와 650℃의 온도에서 실시하였다. 650℃ 크리프 시에는 취약한 금속간화합물인 σ상이 석출하였으며 이것은 크리프수명을 급격히 감소시키는 역할을 하였다. Mo에 대한 W원소의 치환은 일반적으로 σ상의 석출을 지연시킨다고 알려져 있으나, 2wt.%까지 W 치환을 실시한 본 연구범위에서는 크리프 수명 및 최소 크리프속도에 뚜렷한 영향을 미치지 못하였다. 크리프손상의 정도를 평가하기 위하여 크리프시편에 대한 초음파검사를 실시하였다. 크리프온도 600℃에서는 크리프시편의 수명이 증가함에 따라 음속이 비례적으로 증가하였으나 650℃에서는 반대로 감소하였다. The effect of the substitution of Tungsten(W) for Molybdenum(Mo) on the creep behaviour of 22Cr-5Ni duplex stainless steel(DSS) has been investigated. Creep tests were carried out at 600℃ and 650℃. Intermetallic σ phase is precipitated during creep at 650℃, at which creep rupture time was much lower compared with at 600℃. The substitution of W for MO in the duplex stainless steel was known to retard the formation of σ phase. Minimum creep rate and creep rupture time, however, were hardly influenced by the substitution of 2wt.% W. An ultrasonic measurement for the creep specimens has been carried out for the evaluation of creep damage. The sound velocity increases propotionally with the increase of creep rupture time at 600℃ of creep temperature. On the contrary, the sound velocity decreases with the increase of rupture time at 650℃, which can be correlated with the microstructural evolution during creep.

미세공정상에서 전가산기의 해석 및 비교

이우기,김정범 강원대학교 정보통신연구소 2004 정보통신논문지 Vol.8 No.-

In this paper the main topologies of one-bit full adders, including the most interesting of those recently proposed, are analyzed and compared for speed, power consumption, and power-delay product. The comparison has been performed on circuits, optimized transistor dimension to minimize power-delay product. The investigation has been carried out with properly defined simulation runs on a Cadence environment using a 0.25-μw process, also including the parasitics derived from layout. Performance has been also compared for different supply voltage values. Thus design guidelines have been derived to select the most suitable topology for the design features required. This paper also proposes a novel figure of merit to realistically compare n-bit adders implemented as a chain of one-bit full adders. The results differ from those previously published both for the more realistic simulations carried out and the more appropriate figure of merit used. They show that, except for short chains of blocks or for cases where minimum power consumption is desired, topologies with only pass transistors or transmission gates are not attractive. In contrast. the most interesting implementations in terms of trade off between power and delay are the traditional CMOS and Mirror topologies. Moreover, the CPL allow the best speed performance.

HDPE 개질 아스팔트 혼합물의 강도 및 변형특성

김광우,이기호,권오선,고태영 강원대학교 부설 석재복합신소재 제품연구센터 2004 석재연 논문집 Vol.9 No.-

본 연구는 폐비닐 펠렛을 도로포장재료로 재활용하여 자원절약 및 아스팔트 혼합물의 품질향상을 위한 연구이다. 이를 위하여 폐비닐의 첨가량별 배합설계를 수행하여 적정 폐비닐 첨가량과 최적 아스팔트 함량으로 편마암과 화강암 2가지 골재와 폐비닐인 RHDPE의 함량을 4가지로 혼합물을 제작하여 8종류의 재질 혼합물과 2종류의 무개질 혼합물을 제작하였다. 그리고 이 공시체에 대하여 마샬안정도, 간접인장강도 및 Kim test와 반복주행시험 등 실내시험을 통하여 혼합물의 특성을 분석하였다. 폐비닐 첨가량은 RHDPE가 8%일 때 안정도와 간접인장강도 모두 가장 우수한 것으로 나타났고 취성도 나타나지 않았다. RHDPE를 첨가한 혼합물에 대하여 Kim test를 수행한 결과 DR과 DS 모두 높은 상관성을 보였다. 그리고 반복주행시험에서는 RHDPE를 첨가한 혼합물이 일반 혼합물보다 우수하였다. 향후 많은 실험을 통해 RHDPE의 우수성을 입증한다면 소성변형 저항성에 우수한 재료로 이용될 수 있을 것이다. This study is a fundamental research for recycled high-density polyethylene (RHDPE) in asphalt mixture for improving roadway pavement. Marshall mix design was conducted and optimum asphalt content(OAC) was determined for dense-graded surface course mixture by RHDPE content. Marshall stability test, indirect tensile strength (ITS) test, wheel tracking trest and Kim-test were carried out to measure the characteristics of RHDPE-added asphalt concretes. From the results of this study, RHDPE in asphalt mixture if possible. It could be considered that adding too much RHDPE in asphalt mixture is not proper. The optimum content of RHDPE was appeared to be 8%. In Kim-test, statistical analysis was performed for each loading head and aggregate to find out correlation between S_(D) values and each rut parameter. The analysis result showed that S_(D) had very high coefficient of determination with rut parameters on the average.

배추좀나방(Plutella Xylostella Linnaeus)에 대한 새로운 살충활성 분자의 설계

조윤기,최우영,성낙도 충남대학교 농업과학연구소 2007 농업과학연구 Vol.34 No.2

The new insecticidal active molecules from the based on the holographic quantitative structure-activity relationships (HQSAR) between a series of 1-(R₁)-2-(n-octyl)-3-(R₂), 3-(R₃)-pseudothiourea derivatives and their insecticidal activities against Diamond-back moth (Plutella Xylostella Linnaeus) were designed and discussed quantitatively. The most active molecule from the based graphical analyses of atomic contribution maps with the optimized HQSAR C-1 model (q²=0.764 & r²_(ncv)=0.942) was 1-(n-butyl)-2-(t-butyl)-3,3-diisopropylpseudothiourea (P1: pI_(50)=5.30, IC_(50)=1.397 ppm). Therefore, it is suggested that the new designed molecule would increased the activity as much as 23.5 times as compared to X=n-octyl substituent 17(pI_(50)=4.00, IC_(50)=32.86 ppm) which was the highest active molecule in training set compounds.

휘발성 용제(본드)흡입 금단증상으로 인한 경련발작 1례

이기철,정우승,이정호 大韓神經精神醫學會 1991 신경정신의학 Vol.30 No.2

The authors experienced a case of withdrawal seizure of generalized tonic-clonic type after discontinuation of volatile substance abuse. The seizure was well treated with intravenous injection of 4mg lorazepam. The authors report the case with the review of literatures related to the volatile substance abuse.

Modified Hogan 법을 이용한 범인두 부전 환자의 인두피판 성형술

진우정,정기범,이현상,고승오 大韓顎顔面成形再建外科學會 1996 Maxillofacial Plastic Reconstructive Surgery Vol.18 No.4

A competent velopharyngeal sphincter is essential for intelligible speech. If the velopharyngeal incompetence exist, the seal will not be complete during speech, with a resultant hypernasal speech quality. The patient with velopharyngeal incompetence(VPI) may develope other compensatory speech problems. There are many approaches available to correct veolpharyngeal incompetence, which include speech therapy, push back palatorrhaphy, pharyngeal wall implants and pharyngoplasty. This is cases report of velopharyngeal incompetence, which were successfully treated by superiorly based pharyngeal flap, covered with splitted hinge flap of nasal lining mucosa of the soft palate, named modified Hogan method. The advantages of this method are precision in the approximation of the flap due to pentagonal shaped flap design, good flood supply due to omission of the midsagittal incision on nasal lining mucosa, and simplicity than Hogan method.

지난 6년간(1997~2002) 양산리 소주리 지하수의 수질 조사

최우성,정기호 부산대학교 환경문제연구소 2003 環境硏究報 Vol.21 No.-

In this research, we investigated the KMnOc, consumption rate, pH, and the contents of major anions of the ground water fron Soju-ri, Yangsan(during the last 6 years 1997~2002). In this area, average rainfall during the last 6 years was 1,618.3 mm and a monthly average 134.85 mm. The KMnO₄ consumption rate was 0~3.7 ppm NO₃-N concentration was 1.3~6.5 ppm SO₄ concentration was 10~83 ppm, CI concentration was 4~60 ppm and NH₃-N corcentration was 0~0.05 ppm. Zn, Al, and Ou concentration were 0~0.999, 0~0.17, and 0~0.043 ppm respectively. As Pb, Cd, and Hg were not detected

정면밀링가공에서 쟁기력을 고려한 3차원 절사력 모델링

권원태,김기대 한국공작기계학회 2002 한국생산제조학회지 Vol.11 No.2

Cutting force is obtained as a sum of chip removing force and ploughing force. Chip removing force is estimated by multiplying specific cutting pressure by cutting area. Since ploughing force is caused from dullness of a tool, its magnitude is constant if depth of cut is bigger than a certain value. Using the linearity of chip removing force to cutting area and the constancy of ploughing force regardless of depth of cut which is over a certain limit, each force is separated from measured cutting force and used to establish cutting force model. New rotation matrix to convert the measured cutting force in reference axes into the forces in cutter axes is obtained by considering that tool angles are projected angles from cutter axes to reference axes. Spindle tilt is also considered for the model. The predicted cutting force estimated from the model is in good agreement with the measured force.