• 제목/요약/키워드: Segment

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개구리 망막에 있는 광수용세포의 미세구조 (The Ultrastructure of Photoreceptor Cells in Frog Retina)

  • 김진숙;전진석
    • Applied Microscopy
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    • 제25권4호
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    • pp.115-123
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    • 1995
  • This study was carried out to observe the functional ultrastructures of photoreceptor cells in frog(Rana catesbeiana) retina using transmission electron microscope. The photoreceptor cells are divided into two types-rod and cone cells-consist of outer and inner segment. The long outer segment of rod cell contains dense stacks of membrane and formed vertical and horizontal folds. The outer segment of cone cell is small, and vertical and horizontal folds are not exist. The electron dense cytoplasm of rod cell contains compact mitochondria, Golgi complexes, and endoplasmic reticula. The inner segment of cone cell shows low electron density and contains a large lipid droplet in the upper part of inner segment. In addition, cone cell contains many mitochondria, Golgi complexes. rough endoplasmic reticula, ribosomes and numerous glycogen particles. It is believed that these ultrastructural characteristics are closely associated with photoreceptive function of photoreceptor cells in frog retina.

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의약후보물질의 생식독성평가 원칙 및 방법 (Principles and Methods for the Reproductive-toxicological Evaluation of New Drug Candidates)

  • 정문구;김종춘
    • Toxicological Research
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    • 제16권3호
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    • pp.229-238
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    • 2000
  • The purpose of reproductive toxicity studies is to evaluate all effects resulting from paternal or maternal exposure that interfere with conception, development, birth, and maturation of offspring. In 1966, the US Food and Drug Administration (US FDA) published guidelines for a three-segment study for drug testing to examine adverse effects on fertility and pregnancy. Three segments were proposed: Segment I, Study of Fertility and General Reproductive Performance, to provide information on breeding, fertility, nidation, parturition, neonatal effects and lactation: Segment II, Teratological study, to provide information on embryo toxicity and teratogenicity: and Segment III. perinatal and Postnatal Study, to provide information on late fetal development, labour and delivery, neonatal viability, and growth and lactation. The classic guideline is still used to this day with only monor modification throughout the world. In the present review, the principles and methods of reproductive toxicity studies are discussed with special attention given to scientific issues.

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차영상과 ART2 클러스터링을 이용한 스마트폰 기반의 FND 인식 기법 (Smartphone Based FND Recognition Method using sequential difference images and ART-II Clustering)

  • 구경모;차의영
    • 한국정보통신학회논문지
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    • 제16권7호
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    • pp.1377-1382
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    • 2012
  • 본 논문에서는 가전기기에 탑재 된 FND에 표시되는 부호화 된 코드를 스마트폰으로 촬영하여 이로부터 원문데이터를 추출하는 인식기법에 대해 제안한다. 제안하는 스마트폰 기반의 FND 인식 기법은 먼저 차영상을 이용하여 입력되는 영상에서 FND의 위치를 추정한 뒤 RGB값 클러스터링을 통해 Segment를 추출한다. 다음으로 기울어진 Segment에 대한 정규화 과정을 거친 뒤 상대적인 거리를 이용하여 각각의 Segment를 인식한다. 실험을 통해 실제 스마트폰에서 사용 시 속도와 인식률이 모두 양호함을 확인하였다.

우리말 어휘빈도 정보와 분절음 탈락의 관련성에 대한 연구 (Correlation between the frequency of word and the deletion of segment)

  • 차재은
    • 대한음성학회지:말소리
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    • 제47호
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    • pp.1-13
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    • 2003
  • The purpose of this paper is to research the correlation between frequency and the deletion of /w, (equation omitted)/ in Korean. For this purpose, I select 11 words from the frequency data, then, analyze the speech of 20 speakers of standard Korean. As a result, I can find that there is correlation between the frequency and the deletion rate of segment. The rate of deletion is higher in high frequency words, while the rate of realization is higher in low frequency words. Although there is correlation between the frequency and the deletion rate of segment, the feature of segment, prosodic environments are more important in segment deletion.

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쉴드터널 라이닝 세그멘트의 해석과 거동 특성 (Analysis and Structural Behavior of Shield Tunnel Lining Segment)

  • 이환우;김관수;김광양;강대희
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2007년도 정기 학술대회 논문집
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    • pp.757-762
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    • 2007
  • The lining segment which is the main structure of the shield tunnel consists of joints, not continua. Past international and domestic design data have been commonly used for design practices without specific verification about the structural analysis model, design load, and affection of the soil constant of the lining segment. In this study, the propriety is estimated through the comparison between analytical solution and numerical solution for segment analysis and design models of the shield tunnel which is being used internationally and domestically. As a result, the full. circumferential beam jointed spring model (1R-S0) is suggested by considering aspects of convenient use, application to field condition, and accuracy of analysis result. With suggested model, the parameter analysis was conducted for joint stiffness, ground rigidity, joint distribution, and joint number.

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도시철도 운행패턴 변화에 관한 연구 (A Study on the Change of Urban Rail Operating Patterns)

  • 방연근
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 춘계학술대회 논문집
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    • pp.251-256
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    • 2003
  • This study focuses on the development of the conceptual criteria which could be applied to the speed-up strategy of urban rail operation. Down town segment or not, and peak hour or not are the criteria. The author suggests that in the case of down town segment and peak hour urban rail should take the all-stop pattern, if down town segment and off peak hour, then skip-stop pattern, if not-down town segment and peak hour, the A, B skip-stop, and if not-down town segment and off peak hour, the A, B, C skip-stop. If side lines, three rail, or 2 double lines, then express train operation is recommended in the peak hour. Then this study recommends speed-up strategies of each 8 urban lines.

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Method for classification and delimitation of forest cover using IKONOS imagery

  • Lee, W.K.;Chong, J.S.;Cho, H.K.;Kim, S.W.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.198-200
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    • 2003
  • This study proved if the high resolution satellite imagery of IKONOS is suitable for preparing digital forest cover map. Three methods, the pixel based classification with maximum likelihood (PML), the segment based classification with majority principle(SMP), and the segment based classification with maximum likelihood(SML), were applied to classify and delimitate forest cover of IKONOS imagery taken in May 2000 in a forested area in the central Korea. The segment-based classification was more suitable for classifying and deliminating forest cover in Korea using IKONOS imagery. The digital forest cover map in which each class is delimitated in the form of a polygon can be prepared on the basis of the segment-based classification.

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수용성 단백질의 계면상 등온곡선의 모델과 실험적 규명 (Model and Experimental Isotherms of Soluble Proteins at water sur faces)

  • Cho, D.
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2003년도 춘계학술발표논문집
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    • pp.328-330
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    • 2003
  • A surface equation of state for globular proteins at air-water interface accounting for the molecular structure, segment-segment, segment-solvent, and electrostatic interactions was proposed and compared to C-14 isotope experiments. This lattice model comprised a simplifying assumption that all adsorbed segments are in the form of trains. The number of segment adsorbed per molecule in case of bovine serum albumin linearly depended on the surface concentration whereas the lysozyme segments adsorbed at the interface were independent of surface concentration. The segment-solvent(water) interaction for both of proteins were found to be unfavorable owing to the proteins unfolding. From comparison of model computation and experimental data, BSA unfolded more than lysozyne because of the larger surface area of contact.

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실리콘 segment device로부터의 헤파린 방출에 미치는 폴리에틸렌글리콜의 영향 (Effect of Polyethylene Glycol on Release of Heparin from Silicone Segment Devices)

  • 김성호
    • 약학회지
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    • 제29권2호
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    • pp.70-75
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    • 1985
  • The influence of polyethylene glycol derivatives on heparin release from cylindrical monolithic type silicone segment devices was examined in physical saline solution. This water-soluble carrier caused the devices to absorb the water in aqueous media. The release rate of heparin from the devices was increased as molecular weight of polyethylene glycol was increased. Water soluble carrier incorporated into silitone segment devices permits controlled release of heparin that otherwise would be released extremly slowly from the polymer. Heparin released from the silicone segment containing polyethylene glycol showed the first-order kinetics. Without changing the release-pattern, the release rate of heparin could be controlled by varing molecular weight of polyethylene glycol, the water-soluble carrier and depleting polyethylene glycol on the outlayer of devices. The mechanism of release probably showed the creation of pore or microdomine through the devices secondary to the swelling.

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Segment 기반 재난 정보 제공 시스템 설계 (Design of Segments Based Disaster Information Delivery System)

  • 이재영;이승형;안병덕;오정택
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송∙미디어공학회 2019년도 하계학술대회
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    • pp.202-203
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    • 2019
  • 최근 재난 발생 빈도가 증가함에 따라 재난이 발생 시 사람들에게 재난에 대한 정보를 전달하는 중요성이 부각되고 있다. 기존에는 재난이 발생 시 지역단위로 다양한 매체를 통해 사람들에게 정보를 제공 하고 있다. 하지만 지역단위(시군구 or 읍면)로 정보를 제공하고 있어 위험 발생지역과 동일 지역에 있더라도 위험 영향범위 내에 있지 않는 사람에게도 동일한 재난정보를 제공하고 있어 혼란을 야기 할 수 있는 문제점이 있다. 이에 본 논문에서는 재난 발생 지점을 기반으로 Segment 를 생성하고 관리 하여 위험지역의 사람들에게만 정보를 제공할 수 있는 Segment 기반 재난 정보 제공 시스템을 설계 한다. 제안한 시스템은 재난 발생 시 재난 종류에 따라 위험 지역을 세분화 하고 발생 지점을 중심으로 Segment 를 생성한다. Segment 에 포함된 인구를 추출하고 위험 지역 별로 재난 정보를 제공한다.

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