• 제목/요약/키워드: ECM

검색결과 528건 처리시간 0.022초

포아슨 비의 변화를 고려한 수정 ECM 모델 개발 및 아스팔트 콘크리트의 저온 특성 연구 (Development of Modified Effective Crack Model to Take into Account for variation of Poisson's ratio and Low-Temperature Properties of Asphalt Concrete)

  • 권승준;도영수;김광우
    • 한국도로학회논문집
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    • 제3권1호
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    • pp.185-197
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    • 2001
  • 본 연구는 온도에 따라 특성이 변하는 아스팔트 콘크리트의 파괴인성을 규명하기 위하여 기존의 유효균열 모델을 수정하는 연구를 다루고 있다. 본래의 ECM모델은 콘크리트와 같은 고체에 적용되도록 개발되어 재료의 포아슨 비를 고려하지 않는다. 하지만 아스팔트 콘크리트는 온도변화에 민감하여 온도에 따라 포아슨 비가 변화하므로 다양한 온도하에서 정확한 파괴 특성을 알기 위해서는 포아슨 비가 고려되어져야 한다. 3개의 개질아스팔트 결합재를 포함한 4가지 결합재를 사용하여 밀입도 아스팔트 혼합물을 제조하여 초기균열 보에 대한 3점 휨 시험을 $-5^{\circ}C$부터 $-35^{\circ}C$까지에서 수행하였다. 탄성계수, 휨강도 및 파괴인성을 시험을 통하여 구하였다. 시험결과 포아슨비가 고려되는 수정 ECM 공식을 사용하므로서 보다 정확한 값들을 얻을 수 있었다. 폴리머 개질 아스팔트 혼합물이 일반아스팔트 혼합물에 비하여 더 낮은 저온하에서 더 높은 강성과 파괴인성을 유지함을 알 수 있었다.

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소구경 폴리우레탄 인공혈관의 개발을 위한 세포외기질위의 혈관내피세포 배양 (Endothelial Cell Seeding Onto the Extracellular Matrix of Fibroblasts for the Developement of Small Diameter Polyurethane Vessel)

  • 박동국;이윤신
    • 대한의용생체공학회:의공학회지
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    • 제16권1호
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    • pp.1-8
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    • 1995
  • A variety of experiments of endothelial cell seeding onto artificial vessels have been performed. To improve endothelialization, one or two components of the extracellular matrix (ECM) have been used as an underlying matrix. In this study, the whole ECM excreted from fibroblasts was used as an underlying matrix. Fetal human fibroblasts were cultured on a polyurethane (PU) sheet. After a conflu; ence was attained, the cytoskeleton and the nuclei of the fibroblast were destroyed using Triton-X. Mitomycin, or irradiation. Omental microvascular endothelial cells from adult human were seeded onto various substrates. After 12 days in culture, the cells were counted. It was observed that the ECM treated by irradiation had the highest cell number. In addition, the cells on this substrate exhibited the most typical endothelial cell morphology. For preliminary animal experiments the PU vessels (inner diameter, 1.5mm) coated with ECM were implanted in the infrarena] abdominal aorta of rat. After the vessels had been implanted for 5 weeks, it was found that the surface of the PU vessels was completely covered with endothelia] cells. In conclusion, we can state that the fibroblast-derived whole ECM makes a better underlying substrate for the endothelialization of small diameter artificial vessels.

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전자식 선박디젤엔진의 엔진제어기 개발/연구 (A Development Study on an Engine Control Module of an Electronic Marine Diesel Engine)

  • 심한섭;이민광;이강윤
    • 한국기계가공학회지
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    • 제14권5호
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    • pp.134-140
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    • 2015
  • A control program of an engine control module (ECM) was developed, and its control performance was verified on a 750Ps marine diesel engine. The control method was designed for an engine rotational speed control system. For ECM hardware, the commercial rapid control prototype (RCP) ECM was used. The programming tool for control algorithm development was the MatLab/Simulink. The main control algorithm assembled many control models as engine cranking, run, and stall. Each model has sub-models to input/output control signals. The target engine speed was input signal from a speed control lever, and control output signal of the ECM was sent to the unit-injectors for fuel injection. The engine test was performed under various conditions of engine rotational speeds and dynamometer loads. The test results show that the control function of the ECM is suitable for electrical marine diesel engines.

인조혈관재료 표면에 도포된 혈관내피세포의 생리적 변화에 관한 연구 (Physiological Function of Endothelial Cells Cultured on Polyurethsne Coated by ECM)

  • 이윤신;김용배
    • 대한의용생체공학회:의공학회지
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    • 제17권2호
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    • pp.255-262
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    • 1996
  • Antithrombogenic surFace is one of the most important things to the artificial vascular prostheses. This problem will be solved if the surface of prosthesis is covered with endothelial cells. The attachment and the growth of endothelial cells onto vascular prosthesis are very difficult. So many studies have been concentrated on the attachement of endothelial cell. But no good performance of the in uiwo experiments has been shown until now. In this study, we used the whole extracellular matrix (ECM) excreted from fibroblasts as an underlying matrix, and the endothelial cells were seeded to obtain the long term patency of vascular graft(i.e., for the patent 8 week implanted wafts in the animal model of rat). In order to study the antithrombogenic functions of cultured endothelial cells, prostaglandin(PGF 1 a) synthesis and platelet adhesion were assayed. The concentration of PGF a of stimulated group was sisnificantly higher than that of control group(21.97 $\pm$ 3.45 vs 4.93 $\pm$0.71 pg/1000 cells). The platelet adhesion of the polyurethane sheet covered with endothelial cells was lower than that of polyurethane sheet or sheet covered with ECM(1.04$\pm$0.28, 2.87$\pm$0.77, 2.89$\pm$0.70, % radioactivities, respectively). Endothelial cells grew well on polyurethane coated with ECM, synthesized the prostacyclin and functioned well as antithrombogenic. Therefore the endothelialization onto the ECM excreted from fibroblasts may be a good method for the vfudig prosthesis.

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시험 모달 데이터를 이용한 F-16 항공기의 플러터 해석 (Flutter Analysis of F-16 Aircraft Using Test Modal Data)

  • 변관화;전승문
    • 한국항공우주학회지
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    • 제34권4호
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    • pp.76-82
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    • 2006
  • 새로이 개발된 ALQ-X ECM 포드를 장착한 KF-16D 항공기의 플러터 해석을 수행하였다. 해석에 필요한 기체 고유진동모드 데이터를 지상진동시험 결과로써 직접 사용하는 방법을 제시하고 기존 자료를 이용하여 타당성을 확인하였다. 랜딩기어로 지지된 KF-16D 항공기에 대한 지상진동시험 결과를 비행 상태의 모달 데이터로 변환하였다. KF-16D 항공기에 ALQ-X를 장착한 형상과 기존의 ALQ-119 장착 형상에 대한 플러터 속도를 비교함으로써 새로이 개발된 ECM 포드를 기존의 ECM 포드와 동일한 비행영역에서 사용이 가능함을 입증하였다.

Force-mediated proinvasive matrix remodeling driven by tumor-associated mesenchymal stem-like cells in glioblastoma

  • Lim, Eun-Jung;Suh, Yongjoon;Kim, Seungmo;Kang, Seok-Gu;Lee, Su-Jae
    • BMB Reports
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    • 제51권4호
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    • pp.182-187
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    • 2018
  • In carcinoma, cancer-associated fibroblasts participate in force-mediated extracellular matrix (ECM) remodeling, consequently leading to invasion of cancer cells. Likewise, the ECM remodeling actively occurs in glioblastoma (GBM) and the consequent microenvironmental stiffness is strongly linked to migration behavior of GBM cells. However, in GBM the stromal cells responsible for force-mediated ECM remodeling remain unidentified. We show that tumor-associated mesenchymal stem-like cells (tMSLCs) provide a proinvasive matrix condition in GBM by force-mediated ECM remodeling. Importantly, CCL2-mediated Janus kinase 1 (JAK1) activation increased phosphorylation of myosin light chain 2 in tMSLCs and led to collagen assembly and actomyosin contractility. Collectively, our findings implicate tMSLCs as stromal cells providing force-mediated proinvasive ECM remodeling in the GBM microenvironment, and reminiscent of fibroblasts in carcinoma.

플라보노이드의 세포외 기질 관련 유전자 발현에 관한 연구 (A Study on the Expression of Genes Related to Extracellular Substrates of Flavonoids)

  • 이재은;박세연
    • 한국응용과학기술학회지
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    • 제40권5호
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    • pp.1010-1021
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    • 2023
  • 본 연구에서는 flavonoid apigenin과 baicalein의 세포 실험으로 콜라겐 회복효과를 확인하고 전사체 비교 분석을 통하여 collagen 회복 효과를 뒷받침할 수 있는 결과를 제안하고자 한다. 연구 결과 apigenin과 baicalein은 HS68 세포주에서 UV에 의해 손상된 I형 collagen 회복에 효과를 보였으며, 두 물질 모두에서 ECM 관련 유전자들의 발현 변화를 확인하였다. ECM을 조절하는 공통적인 메커니즘을 보일 뿐 아니라 각각 다른 범주의 유전자들을 변화시키는 결과도 보여서, 세포에 다양한 영향을 미치는 것으로 예측할 수 있었다.

TRANS FORM / Product Briefs

  • 한국데이터베이스진흥센터
    • 디지털콘텐츠
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    • 12호통권127호
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    • pp.170-172
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    • 2003
  • 미네소타 에덴프레리에 소재한 스텔런트(www.stellent.com)는 최근 유니버셜 콘텐츠 매니지먼트 7.0을 발표했다. 이 제품은 하나의 공통 제품 아키텍처 내에서 문서 관리, WCM(웹 콘텐츠관리), 협업, 레코드 관리, DAM(디지털자산관리)을 통합하는 유일한 ECM(기업콘텐츠관리) 솔루션이다. 본질적으로 다른 기술들을 통합시킨 ECM 시스템을 활용한 최신 업그레이드 제품과 달리 이번에 내놓은 ECM 시스템 7.0 버전은 공 통 GUI(Graphical User Interface)와 공 통API(Application Programming Interface)를 통해 단일 서버에서 모든 애플리케이션 모듈을 지원한다는 게 회사측 설명이다.

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A Phase-Based Approach to ECM across CP in Korean

  • Kim, Youngsun
    • 한국언어정보학회:학술대회논문집
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    • 한국언어정보학회 2002년도 Language, Information, and Computation Proceedings of The 16th Pacific Asia Conference
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    • pp.205-216
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    • 2002
  • ECM across a CP in Korean poses difficulties from the standpoint of the locality of A-movement/agreement. A phase-based analysis is developed which requires two steps: (i) in the embedded CP, VP/VP containing its VP-internal subject first moves to Spec-CP, which renders the subject accessible to the matrix v, in accordance with Chomsky's Phase Impenetrability Condition; (ii) ECM takes place in a local relation between the matrix v and the embedded subject. It is shown that the otherwise puzzling fact that ECM across a CP, but not Passivization across a CP, is affected by the type of the embedded verb in Korean is accounted for in a principled way, based on the assumption that CP and CP, but not TP and VP, are phases.

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Biomimetic Electrospun Fibers for Tissue Engineering Applications

  • 신흥수
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2011년도 추계학술발표대회
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    • pp.2.2-2.2
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    • 2011
  • The central strategy in tissue engineering involves a biomaterial scaffold as a delivery carrier of cells and a depot to deliver bioactive molecules. The ability of scaffolds to control cellular response to direct particular repair and regeneration processes is essential to obtain functional tissue engineering constructs. Therefore, many efforts have been made to understand local interactions of cells with their extracellular matrix (ECM) microenvironment and exploit these interactions for designing an ideal scaffold mimicking the chemical, physiological, and structural features of native ECM. ECM is composed of a number of biomacromolecules including proteins, glycosaminoglycans, and proteoglycans, which are assembled together to form complex 3-dimensional network. Electrospinning is a process to generate highly porous 3-dimensional fibrous structure with nano to micro scaled-diameter, which can closely mimic the structure of ECM. In this presentation, our approaches to develop biomimetic electrospun fibers for modulation of cell function will be discussed.

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