剪斷變形을 고려한 四邊固定 直交異方性 對稱積層 矩形板의 解析

宋錫銀,李元洪 진주산업대학교 1992 論文集 Vol.31 No.-

本 硏究에서는 재료의 역학적인 특성과 두께가 중립축에 대하여 대칭으로 적층되어 있고 판의 경계가 모두 固定인 直交異方性으로 보강된 積層板의 剪斷變形效果를 해석적인 방법으로 해결하기 곤란한 문제를 有限差分法을 이용하여 해결하기 위하여 기본방정식인 4차의 編微分方程式을 x 및 y방향으로 각각 2차 편미분인 3개의 연립방정식으로 변환하여 유한차분법율 이용하여 해석한 결과 다음과 같은 결론을 얻었다. 1) 판의 길이-두께比가 감소할수록 처짐값이 매우 큰 差를 나타내었다. 따라서, 전단변형의 영향을 무시한 고전적인 방법으로 해석한 결과는 큰 오차를 야기시킨다. 2) 유한차분법에 의한 해석 결과의 정확성을 검증하기 위하여 판의 中央點에서의 처짐값을 비교 검토한 결과, mesh數가 增加함에 따라 誤差가 현저하게 줄어들었고 mesh數가 l7×17일때 0.23%의 매우 정확한 解를 얻었다. 3) 직교이방성대칭적층판에서 ply-angle과 각 층의 조합에 따라 영향을 받는 비틀림은 판의 처짐, 단면력 및 응력에 큰 영향을 주므로 구조물의 역학적인 특성에 따라 재료의 특성을 합리적으로 조성할수 있도록 배치되어야 한다. 이와같이 기본방정식을 연립 편미분방정식으로 변환하여 유한차분법율 이용하면 공학적으로 정도 높은 결과를 얻을 수 있다고 思料되고, 제설계자를 위하여 결과를 도표로 제시하였다. In the recent years the development of high modulus and high strenght fibers bonded in laminated composites has brought a renewed interest in structural elements fabricated of layers, each layer possessing different mechanical properties. A considerable amount of research work has been under progress regarding the elastic behavior of laminated composites, particulary thin plates. The problem of such a plate has studies by several people. Some of them include J.R. Vinson J.M. Whitney, A.W. Lessia, J.E. Ashton and so on. This paper presents some of analysis of generally orthotropic laminated rectangular 4 side-clamped plates including the effects of trasverse shear deformation. When the length of the plate is great as compared with its thickness, conventional methods of structural analysis can be employed. But if the lenght of the plate is short compared with its thickness, no analytical solution seems to be feasible. One of the practical methods of analysis of such preblem is the finite differece technique. When this technique is used to solve this problem, it is desirable to reduce the order of the derivatives in order to minimize the number of the pivotal points involved in each equation. This purpose can be accomplished with relative ease. The fourth-order partial differential equation of plate vending is replaced by an equivalent three of second order partial defferential equations with three dependant variables, namely the deflection and slope deflections. The finite difference technique is then applied to transform these differential equations into sets of linear algebraic equations. In order to solve the resulting matrix equation with a large number of unknowns, a special scheme is used in programing for the compuer. It is hope that engineers will find the paper useful in developing an understanding of laminated plates.

Bupivacaine과 ropivacaine이 Xenopus oocyte에 발현된 HERG 전류에 미치는 영향

김국성,이규승,김효신,손숙진,이상도,김광진,전병화,김윤희,박진봉 충남대학교 의과대학 의학연구소 2003 충남의대잡지 Vol.30 No.1

Bupivacaine is an amide-type local anesthetic widely used for regional anesthesia. Ropivacaine is developed as a less cardiotoxic alternatives to bupivacaine. In the present study, we have analyzed the effects of bupivacaine and ropivacaine on HERG currents expressed in Xenopus oocytes. Bupivacaine and ropivacaine(3∼1,000μM) blocked HERG currents in a concentration dependent manner. EC_(50) was 26.1±3.1μM(n_(R) 0.65±0.04) and 43.5±7.9μM(n_(H) 0.99±0.13) in bupivacaine and ropivacaine, respectively. Bupivacaine and ropivacaine did not affect the activation and deactivation kinetics of HERG channels. However, the drugs decreased the slope conductance measured from fully activated current-voltage relationship curves. These results suggest that bupivacaine and ropivacaine have a similarinhibitory effect on HERG channels, which could be a possible cellular mechanism of LQT or ventricular arrythmia by the drugs.

P53 Impairs Endothelium-Dependent Vasomotor Function Through Transcriptional Upregulation of P66shc

Kim, Cuk-Seong,Jung, Saet-Byel,Naqvi, Asma,Hoffman, Timothy A.,DeRicco, Jeremy,Yamamori, Tohru,Cole, Marsha P.,Jeon, Byeong-Hwa,Irani, Kaikobad Ovid Technologies Wolters Kluwer -American Heart A 2008 Circulation research Vol.103 No.12

<P>The transcription factor, p53, and the adaptor protein, p66shc, both play essential roles in promoting oxidative stress in the vascular system. However, the relationship between the two in the context of endothelium-dependent vascular tone is unknown. Here, we report a novel, evolutionarily conserved, p53-mediated transcriptional mechanism that regulates p66shc expression and identify p53 as an important determinant of endothelium-dependent vasomotor function. We provide evidence of a p53 response element in the promoter of p66shc and show that angiotensin II-induced upregulation of p66shc in endothelial cells is dependent on p53. In addition, we demonstrate that downregulation of p66shc expression, as well as inhibition of p53 function in mice, mitigates angiotensin II-induced impairment of endothelium-dependent vasorelaxation, decrease in bioavailable nitric oxide, and hypertension. These findings reveal a novel p53-dependent transcriptional mechanism for the regulation of p66shc expression that is operative in the vascular endothelium and suggest that this mechanism is important in impairing endothelium-dependent vascular relaxation.</P>

음성정보 기반 건강 자가진단 시스템의 개발

김국성(Cuk-Seong Kim),조동욱(Dong-Uk Cho),박현종(Hyun-Jong Park),박전규(Jeon-Gu Park) 한국통신학회 2018 한국통신학회 학술대회논문집 Vol.2018 No.1

Inhibitory effects of coronary vasodilator papaverine on heterologously-expressed HERG currents in Xenopus oocytes

KIM, Cuk-seong,LEE, Nam,SON, Sook-jin,LEE, Kyu-seung,KIM, Hyo-shin,KWAK, Yong-geun,CHAE, Soo-wan,LEE, Sang-do,JEON, Byeong-hwa,PARK, Jin-bong Springer Science and Business Media LLC 2007 Acta pharmacologica Sinica. Vol.28 No.4

Analysis of Blood Flow-dependent Blood Nitric Oxide Level and Half-life of Nitric Oxide in Vivo

Kim Cuk-Seong,Kim Hyo-Shin,Lee Young-Jun,Park Jin Bory,Ryoo Sung-Woo,Chang Seok-Jang,Jeon Byeong-Hwa Biomedical Engineering Society for Circulation 2003 International Journal of Vascular Biomedical Engin Vol.1 No.2

Endothelial release of nitric oxide (NO) contributes to the regulation of vascular tone by inducing vascular relaxation. To estimate the blood flow-dependent nitric oxide level and half-life (T1/2) of nitric oxide in vivo state, we investigated the change of aortic NO currents during the change of aortic blood flow rate using NO-selective electrode system and electromagnetic flowmeter in the aorta of anesthetized rats. Resting mean aortic blood flow rate was $49.6{\pm}5.6ml/min$ in the anesthetized rats. NO currents in the aorta were increased by the elevation of blood pressure and/or blood flow rate. When the aortic blood flow was occluded by the clamping, aortic NO currents were decreased. The difference of NO concentration between resting state and occluded state was $1.34{\pm}0.26{\mu}M$ (n=7). This NO concentration was estimated as blood flow-dependent nitric oxide concentration in the rats. Also, while the aortic blood flow was occluded, NO currents were decreased with exponential pattern with $12.84{\pm}2.15$ seconds of time constant and $7.70{\pm}1.07$ seconds of half-life. To summarize, this study suggested that blood flow-dependent NO concentration and half-life of nitric oxide were about $1.3{\mu}M$ and 7.7 seconds, respectively, in the aorta of anesthetized rats. The nitric oxide-selective electrode system is useful for the direct and continuous measurement of NO in vivo state.

Controlling the Electronic Structures of Two-Dimensional Materials for New Functionalities with Synchrotron Radiation based-Photoemission Spectroscopy

Chan-Cuk Hwang 한국진공학회 2018 한국진공학회 학술발표회초록집 Vol.2018 No.2

Characterization of functionalized silicon surfaces and graphenes using synchrotron radiation PES

Chan-Cuk Hwang(황찬국) 한국진공학회 2010 한국진공학회 학술발표회초록집 Vol.38 No.-

Bisphenol sulfone산계 고분자의 합성 및 나일론 오염방지성에 관한 연구 (I)

최영주(Cuk Yong Zhu),송승종(Seung Jong Song),윤남식(Nam Sik Yoon) 한국염색가공학회 2000 韓國染色加工學會誌 Vol.12 No.4

공연 텍스트로서의 안톤 체호프 < 벚나무 동산 > 무대화 연구 : 페레스트로이카 이후, 모스크바와 상트페테르부르크 연극무대를 중심으로

김원석 ( Weon Cuk Kim ) 한국드라마학회 2012 드라마연구 Vol.- No.38

Perestroika brought a big change to the Russian society, bringing new movements in economy, society, religion, art and culture. Restricted artists and their works found their rights, and the theatres gained their authority to make productions. Perestroika had let the streams flow again. This era of change and Chekhov`s The Cherry Orchard has a close relationship. The masterpiece was produced through the labor of the Russian revolution. In The Cherry Orchard, the conflict between the new and the old generation is shown - those who attempt to rebuild the society through the revolution, and who tries to keep the old. But this kind of conflict is not portrayed as tragedy in the script. In fact, he insisted that the script is ``comedy``. The ``comedy`` Chekhov mentioned is, so called ``the comedy of situations``. The humour in The Cherry Orchard can be summarized as ``absurd situations`` that comes to the ``less grown adults``. The characters who have childlike innocence confront the harsh reality. They think they should solve the problems but cannot decide which way to solve them. The family of Ranevska hesitate to make a decision and waits for the auction. They would look like children who don`t know much about the world from the point of view of Lopakhin. This contrast has similarities with the situations of the time when The Cherry Orchard was written, as well as that of post Perestroika. And stage directors had presented such Chekhov`s scripts with their own interpretation on the stage as a human being, a member of a nation and the society, and an individual artist. They present unique productions due to their different identities and tastes for art. In the Russian theatrical scene of 80`s and 90`s, major concern for the directors was to find a way to conclude a century and open a new era in the changes of Perestroika. With deep concerns they tried to gaze the age by recreating The Cherry Orchard. They wanted to reflect the reality from the hidden messages in Chekhov`s text about fate of a man and the discussion about the age. In this progress, rather than succeeding the classics and the authority, the directors tried to find an efficient theatrical way to express their original interpretation. For that reason, each productions had unique interpretations and presentations. The mutual influence between the script, stage, and director had become clearer, which makes the modern theatre peculiar. The new belief, theatrical form, and the effort to find more assertive way of expression could be defined as the trend of the times. 현대연극에서 체호프는 다양한 무대에서 다양한 방식으로 선보여져왔다. 20세기 초반 ``연출가``가라는 새로운 권력의 등장으로 기존 연극에서 볼 수 없었던 독특한 시각이 작품 안에 새롭게 배열되면서 체호프의 무대는 그야말로 현대연극 무대에서 새로운 연극언어의 발생지가 되어왔다 해도 과언이 아닐 것이다. 체호프 작품의 무대화는 체호프의 명성에 비례하듯 빈번하지만 그중에서도 < 벚나무 동산 >의 무대화는 그의 여타 작품들에 비해서도 압도적이다. 특히나 러시아 연극사에 있어 페레스트로이카 이후 봇물 터지듯 쏟아져 나온 수많은 < 벚나무 동산 >은 연극사적으로는 물론 사회적으로도 시사하는 바가 크다. < 벚나무 동산 >의 사회적 배경은 19세기 말 러시아에 몰아닥친 금융 자본주의와 그런 변화에 대응하지 못한 미성숙한 귀족들의 행태로 요약될 수 있다. 이러한 상황은 체호프가 < 벚나무 동산 >을 집필할 당시의 상황이었는데, 이는 사회 격변기 속에서의 세대 간의 갈등과 같은 면모에서 1980년대 페레스트로이카의 상황과도 비슷하게 맞아떨어진다. 이에 당대의 연출가들은 < 벚나무 동산 >에 자신의 사회적 시각을 녹이고 미학적 실험을 얹어 다양한 < 벚나무 동산 >을 내어놓은 것이다. 본고는 페레스트로이카 이후 공연된 < 벚나무 동산 > 중 평단에서 가장 주목을 받은 작품 9편을 연구 대상으로 하여 정치, 사회적 맥락에서 작품을 분석함에 그 목적이 있다.