RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 원문제공처
          펼치기
        • 등재정보
          펼치기
        • 학술지명
          펼치기
        • 주제분류
          펼치기
        • 발행연도
          펼치기
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • ESO 기법을 이용한 컴플라이언트 메커니즘 설계

        이원구,박재용,김상락,유진식,한석영 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-

        A compliant mechanism is a mechanism that produces its motion by the flexibility of some or all of its members when the input forces are applied. Whereas the topology optimization based on homogenization and SIMP parameterization has been successfully applied for compliant mechanism design, an ESO approach has not been considered yet for the optimization of these types of systems. This work presents a modified version of the evolutionary structural optimization (ESO) Procedure for its application in topology optimization of compliant mechanisms, It will be shown that an additive version of this method must be adopted in order to achieve the optimum design, since the traditional ESO method's element removal technique is not efficient in this case. The methodology is based on a mutual energy concept for formulation of flexibility and the ESO method. A multi-objective optimization problem is formulated as an application of compliant mechanism design. The procedure has tested in several numerical applications and benchmark examples to illustrate and validate the approach.

      • Si 기판 위에 CeO_2 유전체 박막 성장

        한재원,김상훈,한영기,최무용 성균관대학교 기초과학연구소 1994 論文集 Vol.45 No.1

        CeO_2 single target을 사용하여 on-axis rf magnetron 스퍼터링 방법으로 Si(100) 단결정기판 위에 CeO_2 유전체 박막을 성장시킬 때 기판온도, 산소 부분압력, rf input power, 두께 등의 성장변수들이 박막 성장에 미치는 영향을 조사하여 (ℓ00) 방향 in-situ 성장의 적정조건을 찾는 연구를 하였다. 각기 다른 조건에서 제조된 박막의 X-ray 회절 방법에 의한 구조 분석과 SEM(Scanning Electron Microscopy)에 의한 표면의 미세 구조 분석을 통하여 그 특성을 조사한 결과 기판 온도, 산소 부분압력, rf input power 세기, 박막의 두께가 박막 성장에 결정적인 영향을 미치는 중요 성장 변수임을 확인하였다. CeO_2 박막은 target과 기판사이 거리 50㎜, 총압력 30mTorr일 때 기판 온도 800℃, 산소 부분압력 3 mTon, power 90 W(이때 성장속도 0.83Å/s), 성장시간 2시간(이때 두께 500Å)일 때(ℓ00) 방향으로 잘 성장되는 것을 발견하였다. We have studied systematically the optimum condition for in-situ perparation of CeO_2 thin film on Si(100 substrate by single-target rf-magnetron sputtering method. We examined effects of the substrate temperature, oxygen partial pressure, rf input power, and thickness by studying X-ray diffraction patterns and photographs of scanning electron microscopy of the grown films. We found that all of these parameters influence decisively on the struture of the grown films. We also found that the CeO_2 thin film grows well at∼800℃ of the substrate temperature, 3 mTorr of the oxygen partial pressure, 90 W of the rf input power(corresponding to 0.83Å/s of the deposition rate), and 5000 Å of the thickness for the total sputtering gas of 30 mTorr and the sputtering target of 2 inch diameter used.

      • 사람 태아간의 산호성 과립백혈구형성에서 산호성 과립형성에 대한 미세구조 연구

        송재섭,김경용,이원복,김동창 중앙대학교 의과대학 의과학연구소 1992 中央醫大誌 Vol.17 No.4

        The developmental processes of eosinophilic granule formation were ultrastructural investigation of eosinophilic granulopoiesis in 15 cases of human fetal livers from 8 to 34 weeks of gestation. 1) Numerous vesicles, microgranules and small agranular and granular vacuoles were distributed around the distended Golgi apparatus in myeloblast and eosinophilic promyelocyte. 2) Granular matrix of vacuoles contained small granular vacuoles, serveral vesicles and mutilamellar structures. The granular substance exhibited higher electron density than that of cystic rough endoplasmic reticulum(RER) and was similar partly to that of immature eosinophilic granules. 3) Distended cystic RER was fused to produce matrix of maturing granules with granular vacuoles and immature eosinophilic granules. 4) Immature eosinophilic granule which began to be produced in eosinophilic promyelocyte, had myelin sheath-like structure and debris of vesicles and granular vacuoles and those disappeared immediately. The charicteristic crystalloid inclusions began to develop in immature eosinophilic granule of myelocyte. In summary, it is suggested that vesicles and granular vacuoles as well as RER in the myelocyte and promyelcyte are participating in the formation of immature eosinophilic granules which become mature with the appearance of charicteristic crystalloid inclusion

      • 단면의 성질을 적용한 크기와 회전 변화에 불변인 영상 검사 시스템

        이용중,김태원,김기대,류재엽 한국공작기계학회 2001 한국공작기계학회 춘계학술대회논문집 Vol.2001 No.-

        The purpose of this paper is to develop image inspection system endows an automatic operating and measuring that the moment values are invariant with respect to variable object size and rotation. In this paper, using these moment feature vector with Hu's 7 invariant moment is also given. The charasteristics of section which is applied in the mechanics used moment descriptor of invariant moment detection algorithm for image inspection system. Corresponding rates between 94% and 96% have been achived for all object tested.

      • ESO 기법을 이용한 신뢰성 기반 최적설계

        김상락,박재용,이원구,유진식,한석영 한국공작기계학회 2007 한국공작기계학회 추계학술대회논문집 Vol.2007 No.-

        This paper presents a Reliability-Based Topology Optimization (RBTO) using Evolutionary Structural Optimization (ESO). An actual design involves uncertain conditions such as material property, operational load and dimensional variation. Deterministic Topology Optimization (DTO) is obtained without considering of uncertainties related to the uncertainty parameters. However, RBTO involves evaluation of probabilistic constraints, which can be done in two different ways, the reliability index approach (RIA) and the performance measure approach (PMA). Limit state function is approximated using Monte Carlo Simulation and Central Composite Design for reliability analysis. ESO, one of the topology optimization techniques, is adopted for topology optimization. Numerical examples are presented to compare the DTO with RBTO.

      • 형질전환 제초제저항성 벼 밀양 204호의 농업적 특성

        정응기,이기환,원용재,박향미,전남수,최준호,구연충,한창덕,은무영,김태산,남민희 Plant molecular biology and biotechnology research 2005 Plant molecular biology and biotechnology research Vol.2005 No.

        This study was conducted to investigated the major characteristics of genetically modified rice of "Milyang 204" originated from Dongjinbyeo compared to a non-transgenic rice varieties Dongjinbyeo and Junambyeo. Basta resistant transgenic rice lines carrying bar gene produced by the Yeongnam Agricultural Research Institute were evaluated for their agronomic characters. The transgenic Japonica rice of "Milyang 204" showed inferior phenotypic traits compared to a non-transgenic rice variety Dongjinbyeo and Junambyeo. On the basis of UPOV (Union Internationale Pour la Protaection des Obtentions Vegetables) and NSMO(National Seed Management Office) the transgenic "Milyang 204" showed difference in some traits out of some agronomic traits, such as leaf color, angle of flag leaf, number of spikelets, culm length, white core and white belly compared to the nontransgenic varieties rice.

      • ESO 기법을 이용한 외팔보의 신뢰성 기반 위상최적설계

        김상락,박재용,이원구,유진식,한석영 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-

        This paper presents a Reliability-Based Topology Optimization (RBTO) using the Evolutionary Structural Optimization (ESO). An actual design involves uncertain conditions such as material property, operational load and dimensional variation. The Deterministic Topology Optimization (DTO) is obtained without considering of uncertainties related to the uncertainty parameters. However, the RBTO can consider the uncertainty variables because it has the probabilistic constraints, In order to determine whether the probabilistic constraint is satisfied or not, simulation techniques and approximation methods are developed, In this paper, the reliability index approach (RIA) is adopted to evaluate the probabilistic constraint, In order to apply the ESO method to the RBTO, a sensitivity number is defined as the change in the reliability index due to the removal of ith element. Numerical examples are presented to compare the DTO with the RBTO.

      • 디클로페낙 프로드럭들의 흰쥐 피부 투과

        도희정,조원제,용철순,이치호,김대덕 전남대학교 약품개발연구소 2001 약품개발연구지 Vol.10 No.-

        Various alkyl ester prodrugs of diclofenac were synthesized in order to investigate the relationship between their skin permeation characteristics and physicochemical properties. Solubility in various vehicles was measured at room temperature. I -Octanol/water partition coefficients (Log P) and capacity factors (k') were measured to determine the lipophilicity of the prodrugs. Stability of prodrugs in the skin extract and homogenate was also investigated before conducting the skin permeation studies. Increases in the Log P and capacity factor values were observed when alkyl esters of diclofenac were prepared. Since the aqueous solubility of the prodrugs was not high enough, they were saturated in propylene glycol (PG) for skin permeation studies. Prodrugs were rapidly metabolized to diclofenac, both in skin homogenate and in dermal extract of skin. The skin permeation rate of alkyl ester prodrugs was significantly higher than diclofenac with shorter lag time. Moreover, a parabolic relationship was observed between the permeation rate and the log P values of prodrugs, and the maximum flux was achieved at a log P value of around 4.0.

      • 디클로페낙 프로드럭들의 흰쥐 피부 투과

        도희정,조원제,용철순,이치호,김대덕 영남대학교 약품개발연구소 2002 영남대학교 약품개발연구소 연구업적집 Vol.11 No.-

        Various alkyl ester prodrugs of diclofenac were synthesized in order to investigate the relationship between their skin permeation characteristics and physicohemical properties. Solubility in various vehicles was meastured at room temperature. 1-Octanol/water partition coefficients (Log P) and capacity factors (k") were measured to detemine the lipophilicity of the prodrugs. Stability of prodrugs in the skin extract and homogenate was also investigated before conduction the skin permeation studies. Increases in the Log P and capacity factor values were observed when alkyl esters of diclofenac were perpared. Since the aqueous solubility of the prodrugs was not high enough, they were saturated in propylene glycol (PG) for skin permeation studies. Prodrugs were rapidly metabolized to diclofenac, both in skin homogenate and in dernal extract of skin. The skin permeation rate of alkyl ester prodrugs was significantly higher than diclofenac with shorter lag time. Morecover, a parabolic relationship was observed between the pemeation rate and the log P values of prodrugs, and the maximum flux was achieved at a log P value of around 4.0.

      • KCI등재

        다양한 비스테로이드성 소염진통제의 쥐 피부 투과

        김민정,도희정,조원제,용철순,최한곤,이치호,김대덕 한국약제학회 2002 Journal of Pharmaceutical Investigation Vol.32 No.4

        Rat skin permeation of various nonsteroidal antiinflammatory drugs (NSAIDs) was investigated in vitro using Franz diffusion cell at 37℃. The effect of various skin permeation enhancers was also observed as a preliminary study of developing transdermal delivery systems of NSAIDs. Lipophilicity of NSAIDs was determined from the partition coefficient (log P) in 1-octanol/water and 1-octanol/IPB mutual-saturated solutions. The solubility was determined in water, isotonic phosphate buffer (IPB), and propylene glycol (PG) at 37℃. The rat skin permeation rate of acetaminophen, piroxicam, and aceclofenac was almost negligible, although they were saturated in PG. Addition of 1 % permeation enhancer increased the permeation rate of ketoprofen, ketorolac, and diclofenac. However, the skin permeation rate of ibuprofen did not increase with the addition of various enhancers. Among the permeation enhancers tested, oleic acid was the most effective for various NSAIDs. Based on the daily dose, lipophilicity, and the skin permeation rate achieved in this study, ketoprofen and ketorolac seem to be the most promising drug candidates for transdermal delivery systems, especially when formulated with unsaturated fatty acids, such as oleic acid.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼