단섬유로 강화된 Nylon 6.6/Ionomer 복합재료의 물리적 특성

서광석,박광석,이철호 고려대학교 공학기술연구소 1999 공학논문집 Vol.37 No.1

Physical properties of short glass fiber-reinforced nylon 6,6 and ionomer (Surlyn 9020) composites were studied. While ionomer content was increased from 0 to 30phr, tensile strength and flexural strength were decreased, whereas impact strength had maximum value at 20phr. Permittivity, tans, and volume resistivity had no remarkable difference with the variation of ionomer content, In PEA (Pulsed electroacoustic) experiments, for moisture-free specimens, homocharges were accumulated near electrodes and increased with the increase of ionomer content up to 20phr. It was found that moisture uptake rate of nylon 6,6 was declined due to hydrophobicity of ionomer. For moisture-contained specimens, homocharges were increased with moisture content at first, and then decreased while moisture content saturated. Moisture-ionomer interaction was a major mechanism of homocharge formation.

췌장암에서 Cyclooxygenase - 2 발현의 역할

김은경,이용욱,이규택,최규완,박동일,백승운,이준행,이종균,고광철,이풍렬,이종철,김재준,김완선,공구 대한소화기학회 2001 대한소화기학회지 Vol.38 No.3

Background/Aims: Accumulating evidence suggests that the use of NSAID may reduce the incidence of colorectal cancer. The likely mechanisms of these effects by NSAID is cyclooxygenase-2 (COX-2)-related inhibition of tumor proliferation and induction of apoptosis. The aim of our study was to examine possible roles and clinical significance of COX-2 expression in pancreatic cancer. Methods: Seventy-two pancreatic adenocarcinoma tissue specimens were obtained from surgical resection. After the immunohistochemical staining of the specimens, we examined proliferation activity (assayed by Ki-67 expression), apoptosis (by TUNEL stain), and microvessel density (by CD34 expression). We also investigated the relationship between the immunohistochemical expression of COX-2 and various clinicopathological characteristics. Results: The COX-2 positive rate in pancreatic epithelial cells was 41.7%. Proliferation index (PI) was significant higher in COX-2 positive specimens comparing to negative specimen (p=0.015) and the increase in intensity of COX-2 expression correlated with increasing PI (p=0.036). Apoptotic index (AI) was significantly higher in positivee COX-2 expression than in negative expression (p=0.044), but there was no significant difference in AI/PI between the COX-2 positive and negative specimens (p=0.44). The expression of COX-2 protein did not correlate with microvessel density, sex, age, differentiation, tumor size, stage, metastasis or patients survival. Conclusions: The expression of COX-2 enzyme in pancreatic cancer contributes to tumor proliferation, but is not related to apoptosis, angiogenesis or clinical characteristics. Further study is needed to examine the clinical usefulness of NSAID and COX-2 selective inhibitors.

간세포암과 주위 조직에서의 Transforming Growth Factor-beta 1과 그 수용체의 발현

최규완,백승운,최문석,김소정,이준혁,고광철,이풍렬,이종철,박상종,안병훈,김재준 대한소화기학회 2001 대한소화기학회지 Vol.37 No.4

Background/Aims: Transforming growth factor-beta 1 (TGF-β1) is a potent inhibitor of hepatocyte proliferation and its receptor is known to be involved in the carcinogenesis. This study was designed to compare the expression levels of the TGF-β1 and its receptor in neoplastic cells and its surrounding tissue and to assess their role in hepatic carcinogenesis. Methods: We measured the levels of TGF-β1 mRNA and TGF-β1 receptor II mRNA by semiquantitive RT-PCR for the tumor and its surrounding tissue of 30 patients with hepatocellular carcinoma (HCC). We analyzed the relationship between the expression of TGF-β1 mRNA, TGF-β1 receptor II mRNA and clinicopathological characteristics of HCC. Results: The expression of TGF-β1 mRNA showed no difference between HCC and its surrounding tissue, but the expression of TGF-β1 receptor II mRNA was lower in HCC than in its surrounding tissue (2.47±1.08 vs 3.53±1.50, p=0.00). There was no difference in the expression level of TGF-β1 mRNA and TGF-β1 receptor II mRNAo the clinicopathological characteristics of HCC. However, the ratio of TGF-β1 receptor II mRNA in HCC to that in surrounding tissue was more decreased in HCC with portal vein invasion (0.49±0.22 vs 0.77±0.21, p=0.01). Conclusions: Our data suggest that the loss of TGF-β1 receptor II may play an important role in carcinogenesis and tumor progression of HCC.

허혈성 대장염의 임상 양상과 예후 인자

이미숙,손희정,강태욱,최규완,박동일,백승운,이준행,고광철,이종철,임윤정,이풍렬,김갑철,김재준 대한소화기내시경학회 2001 Clinical Endoscopy Vol.22 No.2

Background/Aims: Colonic ischemia is recognized as the most common vascular disorder of the intestines in the elderly. The severity of the disease may vary considerably with the prevalent benign transient forms, being amenable to conservative treatments and the severe gangrenous forms, requiring surgery. Correct diagnosis is usually made after the ischemic episode is over and colonic ischemia is frequently misdiagnosed. The aim of this study is to identify the clinical patterns and prognostic factors of ischemic colitis. Methods: We found 60 patients with nonoccusive ischemia of the large intestine, We analyzed age, sex, symptoms, signs, associated disease, location, endoscopy, hematologic, histologic, radiologic finding and treatment, retrospectively. Results: The mean age was 60.2±6.3 years. The most common symtoms were abdominal pain or bloody diarrhea. The most common sign was diffuse abdominal tenderness. The most common hematologic findings were anemia and leukocytosis. Associated medical illnesses wer diabetes, rhematoid arthritis and cerebrovascular accident, et al. Both computed tomography (CT) and endoscopy were useful diagnostic tools. The most common involved site was sigmoid colon. 46 patients were treated conservatively and 14 patients were managed surgically. Conclusions: Male gender, those with rebound tenderness, severe anemia, right or total colon involvement as well as rheumatoid arthritis had a poor prognosis. Both CT and endoscopy were useful in predicting prognosis.

저밀도 폴리에틸렌의 전기전도에 미치는 실리콘유의 영향

서광석,이창용,강창균 고려대학교 공학기술연구소 1991 고려대학교 생산기술연구소 생기연논문집 Vol.27 No.1

Electrical conduction characteristics of low density polyethylene with a silicon-oil layer at the surface have been investigated at medium fields ranging from about 75 to 650 ㎸/㎝ over the temperature range of 20 to 100℃. The conduction current of polyethylene increases exponentially with the electric field and gets higher as the temperature increases. The observed conduction behavior was explained in term of the SCLC and tunneling effect. Activation energy ranges from 0.54 to 0.44 eV over the field range of 90∼450 ㎸/㎝ and the charge mobility was estimated from a Child law to be in the order of 10^(-16)∼10^(-14)㎡/V·s. Silicone oil layer modifies the conduction behaviors in polyethylene. Major changes are (1) an increase in conduction currents, (2) a suppression in a rate of change of conduction currents, and (3) a decrease in activation energy.

고에너지 전자빔투사방법을 사용한 TiB2/Ti 표면합금화 재료의 제조 연구

구양모,이성학,어광준,김낙준,오준철 대한금속재료학회(대한금속학회) 1998 대한금속·재료학회지 Vol.36 No.12

The present study is concerned with the fabrication and the microstructural analysis of a TiB₂/Ti surfacealloyed material fabricated by high-energy electron beam irradiation. The mixture of TiB₂ powders and flux was deposited on a Ti-10V-2Fe-3Al alloy substrate, and then electron beam was irradiated on these mixture using an electron beam accelerator. The melted region of about 1.5 ㎜ thickness was homogeneously formed without pores or cracks, and was composed of primary and eutectic TiB borides in the β phase matrix. The formation of these TiB borides greatly improved hardness, especially high-temperature hardness up to 450℃. These findings suggested that the surface-alloying method using high-energy electron beam irradiation was economical and useful to the development of new advanced materials with improved high-temperature properties.

Glutaraldehyde 와 자동 세척기를 이용한 내시경 소독방법의 임상에서의 유용성

김영호,손희정,윤성원,최규완,이남용,백승운,이준행,고광철,이풍렬,이종철,송재훈,안병훈,김재준,최원혁,홍일철 대한소화기내시경학회 2001 Clinical Endoscopy Vol.22 No.6

Background/Aims: Safety of endoscopic procedures has been a major issue over the last 10 years. Most endoscopy units use 2% glutaraldehyde and automated endoscope reprocessors (AERs) for disinfecting gastrointestinal endoscopes. We attempted an in-use evaluation of the current reprocessing procedures. Methods: Thirty flexible endoscopes were randomly collected just after upper endoscopic examinations and were disinfected using 2% glutaraldehyde in an AER. Cultures were taken from biopsy channels (S-l), tip of the insertion tubes (S-2), umbilical cords (S-3), and angulation knobs (S-4). Results: In 63,3% (19/30) of endoscopes, there was no microbial contamination after disinfection procedures. The culture positive rates of S-l, S-2, S-3, and S-4 samples were 20,0%, 0.0%, 3.3%, and 20.0%, respectively. Microorganisms of 13 species were identified, but there was no pathogen related with reported infectious complications after endoscopic procedures. Conclusions: Current disinfection procedure using 2% glutaraldehyde and an AER appears to be very effective in decontaminating patient-used endoscopes. Low level microbial contamination of endoscopes after conventional reprocessing methods may not impose great risk on patients.

역류성 식도염 환자에서 Helicobacter pylori 치료 1 년 후 증상과 내시경적 변화

김영호,손희정,최규완,박동일,백승운,이준행,고광철,이풍렬,이종철,임윤정,김재준 대한소화기내시경학회 2001 Clinical Endoscopy Vol.24 No.1

녹색성장 정책의 변화와 법제적 과제

이광윤 ( Kwang Youn Lee ) 경상대학교 법학연구소 2014 法學硏究 Vol.22 No.3

한국과 프랑스의 전 정권에서 녹색성장정책은 핵심 국정과제였다. 한국에서 이명박 정부는 녹색기술과 녹색산업의 창출, 녹색건축물 및 녹색생활의 정착 등 저탄소 녹색성장을 효율적·체계적으로 추진하기 위하여 2010년 1월 13일 저탄소 녹색성장 기본법을 제정하였다. 프랑스에서도 사르코지 정부는 생산에 대한 에너지 소비와 이산화탄소를 줄일 수 있는 기술과 저탄소 활동의 개발을 핵심 정책으로 삼았다. 이를 위해 과감한 미래지향적인 “환경 그르넬”을 통하여 다양한 목표를 설정하였다. 그러나 정권이 교체되면서 양국의 녹색성장정책은 핵심정책에서 밀려나는 모습을 보였다. 박근혜 대통령은 취임 후 창조경제만을 강조할 뿐 녹색성장이란 용어를 거의 사용하지 않았다. 실제 박근혜 정부 출범 1년차에 온실가스 정책들은 속도가 떨어졌다. 물론 박근혜 정부도 ‘녹색성장 정책이 ‘MB표`` 정책이라는 이미지가 너무 강해서 전면에 내세우지 않는 것일 뿐 완전히 폐기한 것은 아니다’고 한다. 실제 이상일 의원은 2014년 정부예산 중 창조경제 사업을 분석한 결과 이 중 33%가 이명박 정부의 ‘녹색사업’을 그대로 가져온 것이라고 지적하기도 하였다. 프랑스의 올랑드 대통령도 정권 초에는 ‘일자리 창출에만 골몰하고 있고, 녹색성장에 대해서는 신경조차 쓰지 않는다.’는 비판을 받기도 하였다. 하지만 결국은 대세에 따라 2013년 9월 2차 환경회의 이후 올랑드 대통령은 에너지전환 법제의 마련이 5개년 계획에 있어 가장 핵심적인 선결과제임을 강조하였다. 이처럼 녹색성장정책은 이제 더 이상 정권의 성격에 따라서 포기할 수 있는 정책이 아니다. ‘일자리 창출’도 중요하지만 ‘지구온난화에 따른 재난의 방지’도 강조돼야 하기 때문이다. 앞으로 녹색성장정책이 지속적일 수 있도록 녹색성장에 관한 법제를 법전화하는 것도 고려해 봐야 하겠다. La declaration du President de la Republique francaise marquee par un objectif : celui de la croissance verte Cette declaration etait attendue, alors que depuis son election, Francois Hollande n’a pas donne beaucoup de signes encourageants sur le terrain du developpement durable. Cela supposait de fixer un objectif - un cap - et les principaux moyens pour y arriver. Un cap pour passer du monde d’hier a celui de demain. Le plus important, de la declaration du Chef de l’Etat : A nous de faire que la lutte contre le rechauffement climatique soit non seulement une cause planetaire, europeenne, nationale, mais le levier d’un nouveau modele de croissance a la fois intelligent, durable et solidaire. La France, et j’en prends ici l’engagement, se mobilisera dans la transition energetique. Voila le cap, la transition. Le 19 decembre 2012, Park Geun-hye remporte l`election presidentielle. La transition entre presidents sud-coreens, tous deux conservateurs, se fait dans un climat tendu, marque par de nouvelles affaires qui ecornent l`image de la future dirigeante Park Geun-hye. Son predecesseur, Lee Myung-bak, avait joue la croissance verte pour relancer le pays. Park Geun-hye parie sur la modernite. Park Geun-hye lance un plan d`economie creative, associant etroitement industrie et culture. La reticence du gouvernement place pour assurer le suivi avec le "bas-carbonne de la croissance verte" politique promu par Lee. L`approche de Park n`est pas sans precedent. il a ete presque de routine dans l`histoire de la politique coreenne pour les nouveaux dirigeants nationaux a degrader leurs predecesseurs et presente l`ordre du jour de la politique differentielle. il a souvent ete le cas. La presidente Park Geun-hye a souligne qu’il y a une necessite de changer le paradigme de notre economie d’une maniere fondamentale par une economie creative afin de surmonter la crise de la croissance sans creation d’emplois. Afin de traverser cette periode de crise, nous avons besoin d’un changement radical de paradigme. La Presidente Park Geunhye, a declare qu’ Il est possible de concretiser le projet d’une economie creative en associant les technologies scientifiques aux TIC, de meme qu’en alliant l’industrie et la culture a la creativite et l’imagination. Malgre le changement du slogan des gouvernements, les perspectives majeurs de l’administration de nouveau gouvernement de Park Geunhye, ne sont pas contradictoires a la politique de la croissance verte concernant la convergence des technologies de l’administration de Lee Myung-bak. Alors que l`administration du president Park Geunhye preconise une economie creative, il a ete revele qu`un nombre important de projets proposes lies a l`economie creative sont identiques a projets de l`economie verte mis en œuvre par le gouvernement de Lee Myung-bak. Malgre les preoccupations qu`elle a affaibli son engagement, la Coree reste determinee a combattre le rechauffement climatique en poussant a travers des projets de reduction de carbone a la maison et le renforcement de la cooperation internationale. La croissance verte doit etre mise en place avec un accent mis sur l`economie creative destinee a creer de nouveaux marches et emplois a travers des idees innovantes et la convergence (des industries)( Le Premier ministre Chung Hong-won, le 21 oct. 2013)Le slogan de Park Geunhye economie creative englobe la croissance verte, et ce sommet et le devouement de GCF sont tous des signes que la croissance verte continue d`etre un enjeu important dans le gouvernement coreen actuel. La constitution et les statuts doivent etre rationalisees pour assurer la stabilite de la mise en œuvre des politiques de croissance verte. Modifications constitutionnelles devraient etre plus souples afin de renforcer la competitivite de la Coree comme un Etat contemporain. Recherche pratique et flexible des attitudes legislatives sont necessaires. Processus de legislation doit etre plus democratique, en permettant la participation des plusieures parties, les parties prenantes et les experts.

韓國 근대 산수화의 조형성 고찰

이광수(Lee Kwang Su) 한국미술교육학회 2013 美術敎育論叢 Vol.27 No.1

근대 전환기에 한국의 산수화는 전통의 계승과 현대성의 표출이라는 문제에 직면한다. 게다가 일제 강점기와 큰 대화라는 역사적 소용돌이에 전통과 자신의 정체성에 대한 물음은 오늘 날에도 여전히 한국화의 담론으로 이어지고 있다. 이러한 시기 조선의 진경산수를 계승하고 이를 토대로 자신의 개성과 양식을 확립한 화가로 노수현, 이상범, 변관식을 거론하고 있는데, 이 세 화가는 문인화에 대한 이해를 바탕으로 자신의 예술 세계를 확립하고 근대 한국 산수화의 새 지평을 열었다는 공통점을 가지고 있다. 그러나 한국의 화단은 일제 강점기라는 특수한 상황과 해방 후 서구 문물의 충격 속에 그 전통성을 일정 부분 상실하기도 하며 중국이나 일본과 다른 양상이 전 개되고, 화론에 대한 답론은 상대적으로 활발하지 못한 부분이 있기도 하다. 하지만, 그들의 예 술에 대한 열정은 한국화단에 소중한 족적을 남기고 있으며, 그들 의 변화되는 화풍에서 충분히 한국화의 조형적 특성을 보여주었다고 생각한다. 이 세 대가의 예술적 성과와 업적은 그동안 많은 연구를 통해 이미 소개되어 있다. 이에 본 연구자는 시각을 달리하여, 의경론(意境論)을 통해 그들의 예술관을 살펴 보고자 하였다. 의경 이란 용어는 우리에게 아직은 생소할 수도 있지만, 점차 확대 되는 추세이고 중국의 경우 이미 예술철학의 한 분야로 자리 잡고 있어, 이 이론을 통한 고찰은 그들의 조형 의식을 드러내는 데 효과적이라고 판단하였다. Korean modern landscape painting has the same way of the periodically changing period because of the Japanese colonial era. inflow of Western painting method. etc. In the stream. representative painters creating modern landscape paintings initiatively can be Noh. Soo Hyun. Lee. Sang Bum and Byun. Kwan Sik. They have common things that they were educated direclty by Jo. Suk Jin(趙錫晉. 1885-1920) and An. Joong Sik (安中植. 1861-1919) who are representative landscape painters at the end of the Joseon Dynasty. their root is in the traditional style of painting and they show innovative style of painting by introducing realistic viewpoint actively after the Japanese colonial era. This study will consider formative awareness of Noh. Soo Hyun. Lee. Sang Bum and Byun, Kwan Sik who are representative painters of modern landscape painting through the Yi Jing factor shown their paintings. oh, Soo Hyun expressed Yi Jing landscape through his ideal landscape and Lee. Sang Bum and Byun. Kwan Sik expressed traditional landscape with the most creative method of expression by exploring real landscape or sutra landscape. Of course, they shouldn't manufacture works by recognizing Yi Jing or aesthetic concept at that time and they don't seem to discuss directly Yi Jing through the painting discussion like Chinese painters. Therefore. it can be difficult to substitute the theory of Yi Jing uniformly, but it was judged to consider formative characteristics by finding Yi Jing factors sufficiently from their painting achievements and working characteristics. It is related to the tradition of painting in the literary artists' style to some degree. But. the most important thing is common thing that three painters created inner warmth newly. And. it's significant that they opened a new prospect of Korean modern landscape painting by sublimating it in their own archetype.