• Title/Summary/Keyword: Whorl

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Simulation of Amplification Characteristics of Ultrashort Laser Pulse Amplification using Raman Backscattering (라만 후방향 산란을 이용한 레이저 펄스 증폭에서 나타나는 증폭 특성의 시뮬레이션)

  • Kim, Jincheol;Lee, Hae-June;Kim, Guang-Hoon;Kim, Changbum;Kim, Jong-Uk;Hyyong Suk
    • Proceedings of the Optical Society of Korea Conference
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    • 2002.07a
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    • pp.230-231
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    • 2002
  • Recently, analysis of transient Raman backscattering in a plasma reported(2.3) that it is possible to reach 10$\^$17/ W/cm$^2$ for 1 micrometer wavelength laser pulse with a counter-propagating pump pulse. The basic mechanism is like this : whorl the two counter-propagating waves in a plasma satisfy the condition of Raman backscattering, w$\_$0/ : w$\_$1/ + w$\_$p/, energy is transferred from the long pulse to the short pulse via three wave interaction(4). (omitted)

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A Study On Singular Points Extraction Algorithm for Finger Classification (지문 영상 분류를 위한 특이점 추출 알고리즘에 관한 연구)

  • 오창섭;최경삼;조성원
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2000.11a
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    • pp.319-322
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    • 2000
  • 본 논문에서는 지문영상으로부터 제안한 알고리즘을 이용하여 특이점(Core, Delta)을 추출한 후 특이점의 개수와 종류에 따라서 5가지 부류(arch, tented arch, left loop, right loop, whorl)로 지문영상을 분류하였다. 지문영상을 8*8블록과 16*16블록으로 분할한 후 3*3 Sobel 마스크를 씌워서 대표 방향을 구하였다. 또한 블록으로 분할한 영상으로부터 분산을 구하여 전경과 배경을 분리(segmentation)시켜 수행속도를 향상시켰다. 전처리 과정으로는 일정한 블록마다 임계값을 다르게 적용시키는 블록 이진화 기법을 사용하였으며 특이점을 추출하기 위해서 서로 크기가 다른 2개의 블록으로 영상을 분할하였다. 우선 8*8블록으로 영역을 분할한 후 방향 성분을 구하고 특이점들을 추출하였다. 이 경우 잡영 때문에 특이점이 너무 많이 추출되는 문제점이 있으므로 이러한 해결책으로 16*16블록으로 영역을 분할하여 방향 성분을 구하고 특이점을 추출하였다. 이렇게 다른 두 영역에서 동시에 나타나는 특이점을 후보 특이점으로 잡아서 그 후보 특이점 주변으로 Poincare 지수를 적용하여 확실한 특이점을 선택한 후 5가지의 지문 형태로 분류하였다. 실험결과 대부분의 지문영상에 대하여 강건한 분류 특성을 보이고 있음을 확인하였다.

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Fine Needle Aspiration Cytology of Meningioma Presenting as a Neck Mass (경부 종괴로 나타난 수막종의 세침흡인 세포학적 소견)

  • Yim, Hyun-Ee;Park, Young-Nyun;Lee, Kwang-Gil
    • The Korean Journal of Cytopathology
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    • v.3 no.2
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    • pp.94-99
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    • 1992
  • Meningioma is the most common neoplasm of central nervous system which is hardly diagnosed by cytologic examination. However, preoperative cytologic diagnosis can be easily made in the case of extracranial meningioma, especially in head and neck lesion. We recently experienced a case of fine needle aspiration cytology of meningioma in sub-mandibular area of a 24 year-old male patient. The smear revealed high cellularity in the clean background. individual tumor cell of nests or syncytium had round or oval nuclei with fine chromatin and moderate amount of lightly stained cytoplasm with indistinct margin. Characteristic cellular whorls, intranuclear inclusions and scattered psammoma bodies made it easy to diagnose a meningioma.

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Design of a Microwave Active Resonator Using Defected Ground Structure with Islands (DGSI) (격리패턴을 지닌 결함접지구조를 이용한 초고주파용 능동공진기)

  • Hwang, Mun-Su;Oh, Seong-Min;Ahn, Dal;Lim, Jong-Sik
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.10
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    • pp.1814-1819
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    • 2007
  • A new active resonator using defected ground structure with islands (DGSI) is proposed. The proposed resonator is composed of the conventional microstrip line with DGSI and negative resistance of active devices. The negative resistance part is realized by field effect transistor (FET) series feedback circuits. The characteristic of the proposed resonator with DGSI is improved by combining the negative resistance part with the parallel microstrip line structure with islands, where the electric field is formed the most strongly. The measured improvement of the proposed active resonator with DGSI are 4.55dB and 0.32dB in S21 and S22, respectively, at the resonant frequency whorl it is compared to the existing passive resonator having DGSI only.

A Syntactic and Semantic Approach to Fingerprints Classification (구문론과 의미론적 방법을 이용한 지문분류)

  • Choi, Young-Sik;Sin, Tae-Min;Lim, In-Sik;Park, Kyu-Tae
    • Proceedings of the KIEE Conference
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    • 1987.07b
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    • pp.1157-1159
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    • 1987
  • A syntactic and semantic approach is used to make type classification based on feature points(whorl, delta, core) and the shape of flow line around feature points. The image is divided into 30 by 30 subregions which are represented in the average direction and 4-tuple direction component. Next the relaxation process with singularity detection and convergency checking is performed. A set of semantic languages is used to describe the major flow line around the extracted feature points. LR(1) parser and feature transfer function are used to recognize the coded flow patterns. The 72 fingerprint impressions is used to test the proposed approach and the rate of the classification is about 93 percentages.

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Morphological Differences of the Shells of Parafossarulus manchouricus ( Prosobranchia : Birthyniidae ) in Korea (한국산 쇠우렁 ( Parafossarulus manchouricus ) 패각의 형태학적 비교)

  • 김재진;최임순
    • The Korean Journal of Malacology
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    • v.3 no.1
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    • pp.35-43
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    • 1987
  • Morphological variations of six Korean and one Japanese populations of Parafossarulus manchouricus were observed. Mean length of shell was 9.36mm(n=376), and mean width was 8.0mm. Average aperture length and width were 4.72 and 3.78mm, respectively. Number of whorl ranged from 3.5 to 5.25(at most 4.5)in all popuiations . Yangsoori population had no spiral line or spiral keel, but ther populations had spiral lines. Number of spiral line on their penultimate shorls ranged 4 to 14.The lips of aperture were generally thickened, except in some Chongpyong, Haman and Fukuoka populations. The most of shell was eroded in only apex part and/ or in othker sculpture, especially Yangsoori population was heavily eroded.

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The Characteristics of High Ozone Concentration.Yield Multi-discharge Type Ozonizer for Water Environment Improvement (수질환경개선용 고농도·고수율 다중방전형 오존발생기의 특성)

  • ;宋炫直
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.13 no.2
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    • pp.203-203
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    • 1999
  • In this paper, high concentration·yield multi-discharge type ozonizer( MDO ) of new discharge type using superposed silent discharge was designed and manufactured. MDO can be consisted with 3 kind of superposed silent discharge type ozonizer( SDO ) in accordance with power supply method that supplying power, which has 180[°] phase difference, to 3 electrodes and double gap. At the moment discharge characteristics and ozone generation characteristics of each SDO were investigated in accordance with quantify of supplied gas, the number of SDO, and the shapes of each SDO. In result ozone generation characteristics of 17185[ppm] and 783[g/kWh] were obtained, and whorl ozone of 17185[ppm] was in contact with dyeing water waste decolonization characteristics was excellent, so it confirmed that MDO could be used as water environment improvement facility.

Systematic Studies on Some Korean Woody Plants - Floral Morphology of Magnoliaceae and Illiciaceae - (한국산 목본식물에 대한 계통분류학적 연구 - 목련과와 붓순나무과의 꽃의형태 -)

  • 선병윤
    • Journal of Plant Biology
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    • v.28 no.4
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    • pp.317-327
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    • 1985
  • Floral morphology of Magnoliaceae and Illiciaceae in Korea is investigated. Magnoliaceae has long and elongate floral axis where numerous stamens and pistils are pistils are spirally arranged, whereas Illiciaceae has short floral axis and pistils are arranged in a single whorl on the axis. The stamens are basically similar in both families; winged and broad filament, prominant connective, long sporangium, and no clear limitation between fertile and sterile parts, which are primitive characters in stamen. The ovaries are the conduplicate type, in both, with decurrent stigma, stigmatic surface confined to stylar position, and no distinct style. Magnoliaceae has one locule and two ovules, whereas Illiciaceae has one locule and one ovule. The ovule is anatropous or hemianatropus, and has bitegmic integument and crassinucellate nucellus.

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Systematic Studies on Some Korean Woody Plants -External Morphology of Lauraceae- (한국산 목본식물에 대한 계통분류학적 연구 -녹나무과의 외부 형태-)

  • Sun, Byung-Yun
    • Journal of Plant Biology
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    • v.27 no.3
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    • pp.129-138
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    • 1984
  • Floral structures of 11 korean lauraceous species belonging to six genera have been studied. Machilus is a primitive genus having relatively large bisexual flower, six tepals and staminodes in fourth whorl of stamen. The flowers of Neolitsea are highly reduced state as unisexual flower, six stamens arranged to three whorls and no staminode in the flower, so regared as more advanced group. Intrafamilial classification systems of Nakai (1939) and Pax (1891) are more reasonable but still have some discrepancies with results. The origin of tepals of this group has been a long controversial problem; whether the differentiation of tepals occur. Teratological study of Lindera erythrocarpa, inner tepals of this group must be originated from the staminode and outer tepals from leafy tepals. Although morphological differentiation does not sitll occur, inner and outer whorls of tepals are originated through different way.

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An experimental study for the filling balance of the family mold (Family 금형의 충전 밸런스를 위한 실험적 연구)

  • Cha B. S.;Rhee B. O.;Park H. P.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2005.09a
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    • pp.132-140
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    • 2005
  • It is well known that the family-mold has an advantage to reduce the cost for production and mold. However, defects are frequently occurred by over packing the smaller volume cavity during molding, especially whorl the family-mold has a volumetric difference between two cavities. In this study, we confirmed the cavity-filling imbalance by the temperature and the pressure sensors, and developed a variable-runner system for the cavity-filling balance. We carried out experiments fur balancing the cavity filling in the family-mold with the variable-runner system, and confirmed a balanced cavity-filing through analyzing the temperature and pressure change in each cavity as the cross-sectional area of the runner changed. We also examined the influence of the injection-speed to the balancing-capability of the variable-runner system in the experiment.

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