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Multiscale Regularization Method for Image Restoration (다중척도 정칙화 방법을 이용한 영상복원)

  • 이남용
    • Journal of the Institute of Convergence Signal Processing
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    • v.5 no.3
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    • pp.173-180
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    • 2004
  • In this paper we provide a new image restoration method based on the multiscale regularization in the redundant wavelet transform domain. The proposed method uses the redundant wavelet transform to decompose the single-scale image restoration problem to multiscale ones and applies scale dependent regularization to the decomposed restoration problems. The proposed method recovers sharp edges by applying rather less regularization to wavelet related restorations, while suppressing the resulting noise magnification by the wavelet shrinkage algorithm. The improved performance of the proposed method over more traditional Wiener filtering is shown through numerical experiments.

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CT Findings of Desmoid Tumor arising at Abdominal Wall: Two Cases Report (복벽에 발생한 데스모이드 종양의 급속 조영 CT 소견 : 2례 보고)

  • Cho, Dae-Hyoun;Cho, Jae-Ho;Chang, Jae-Chun
    • Journal of Yeungnam Medical Science
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    • v.12 no.2
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    • pp.386-392
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    • 1995
  • Desmoid tumor is a type of fibromatosis usually arise in deep musculo-aponeurotic structures, primarily of the trunk and extremities. It is characterized by proliferation of fibroblastic tissue and does not metastasize but may be locally aggressive. Eventhough the surgical margin reveals clean, recurrence often occurs. To analyze the extent of the tumor and homodynamic characteristics exactly, we performed IV bolus CT. Desmoid tumors show peripheral rim enhancement on early phase scan and more strong, central enhancement on late phase IV bolus CT, which reflects abundant fibroblastic components of the tumor. We report two cases of pathologically confirmed desmoid tumor performed IV bolus CT.

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Estimation of the Convective Boundary Layer Height Using a UHF Radar (UHF 레이더를 이용한 대류 경계층 고도의 추정)

  • 허복행;김경익
    • Korean Journal of Remote Sensing
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    • v.17 no.1
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    • pp.1-14
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    • 2001
  • The enhancement of the refractive index structure parameter $C_n^2$ often occurs where vertical gradients of virtual potential temperature ${\theta}_v$ and mixing ratio q have their maximum values. The $C_n^2$ can be a very useful parameter for estimating the convective boundary layer(CBL) height. The behavior of $C_n^2$ peaks, often used to locate the height of mixed layer, was investigated in the present study. In addition, a new method to determine the CBL height objectively using both $C_n^2$ and vertical air velocity variance ${\sigma}_w$ data of UHF radar was also suggested. The present analysis showed that the $C_n^2$ peaks in the backscatter intensity profiles often occurred not only at the top of the CBL but also at the top of a residual layer or at a cloud layer. The $C_n^2$ peaks corresponding to the CBL heights were slightly lower than the CBL heights derived from rawinsonde sounding data when vertical mixing owing to weak solar heating was not significant and the height of strong vertical ${\theta}_v$ gradients were not consistent with that of strong vertical q gradients. However, the $C_n^2$ peaks corresponding to the CBL heights were in good agreement with the rawinsonde-estimated CBL hegiths when vertical mixing owing to solar heating was significant and the vertical gradient of both ${\theta}_v$ and q in the entrainment zone was very strong. The maximum backscatter intensity method, which determines the height of $C_n^2$ peak as the CBL height, correctly estimated the CBL height when the $C_n^2$ profile had single peak, but this method erroneously estimated the CBL height when there was a residual layer or a cloud layer over the top of the CBL. The new method distinguished when there the CBL height from the peak due a cloud layer or a residual layer using both $C_n^2$ and ${\sigma}_w$ data, and correctly estimated the CBL height. As for estimation of diurnal variation of the CBL height, the new method backscatter intensity method even if the vertical profile of backscatter intensity had two peaks from the CBL height and a residual layer or a cloud layer.

Foraging Behavior and Preys in Relation to Feeding Site Types of the Eurasian Oystercatcher (Haematopus ostralegus osculans) during the Breeding Season in Yubu Island, Korea (유부도 일대에 서식하는 검은머리물떼새 (Haematopus ostralegus osculans)의 번식기 섭식지 유형에 따른 섭식행동과 먹이원)

  • Lee, Sang-Yeon;Choi, Yu-Seong;Joo, Sungbae;Jeong, Gilsang;You, Young-Han
    • Korean Journal of Ecology and Environment
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    • v.51 no.2
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    • pp.184-191
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    • 2018
  • During the breeding season, some Eurasian Oystercatchers (Haematopus ostralegus osculans) in Yubu Island foraged in the open mudflat area nearby the breeding ground, instead of the tide water line area, main feeding site throughout the year. We found significant differences in foraging behavior and prey species diversity between the two different feeding site types. Even though the birds took more steps for most probably searching preys, their feeding success was much lower in the open mudflat area than the tide water line area. The multiple peck and boring methods were more frequently adopted to catch polychaetes on the open mudflat area, whereas the single peck method was dominant and gastropods and bivalves were main preys in the tide water line area. This study suggests that the bird shows flexible foraging strategy of shifting feeding site, foraging behavior and preys for better reproductive success.

The Obstacle Avoidance Algorithm of Mobile Robot using Line Histogram Intensity (Line Histogram Intensity를 이용한 이동로봇의 장애물 회피 알고리즘)

  • 류한성;최중경;구본민;박무열;방만식
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.8
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    • pp.1365-1373
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    • 2002
  • In this paper, we present two types of vision algorithm that mobile robot has CCD camera. for obstacle avoidance. This is simple algorithm that compare with grey level from input images. Also, The mobile robot depend on image processing and move command from PC host. we has been studied self controlled mobile robot system with CCD camera. This system consists of digital signal processor, step motor, RF module and CCD camera. we used wireless RF module for movable command transmitting between robot and host PC. This robot go straight until recognize obstacle from input image that preprocessed by edge detection, converting, thresholding. And it could avoid the obstacle when recognize obstacle by line histogram intensity. Host PC measurement wave from various line histogram each 20 pixel. This histogram is (x, y) value of pixel. For example, first line histogram intensity wave from (0, 0) to (0, 197) and last wave from (280, 0) to (2n, 197. So we find uniform wave region and nonuniform wave region. The period of uniform wave is obstacle region. we guess that algorithm is very useful about moving robot for obstacle avoidance.

MICROSCOPIC OBSERVATIONS OF FAT TRANSLOCATION IN THE TISSUE OF YELLOW CORVENIA DURING SALTING AND DRYING ("굴비" 제조과정중의 지방의 이동에 대한 조직학적 관찰)

  • PYEUN Jae-Hyeung;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.1 no.2
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    • pp.63-71
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    • 1968
  • Salted and dried yellow corvenia(Pseudosciaena manchurica), so called 'Gul-bi', is one of nation-widely consuming fish foo::ls. It is suitable for a long term preservation and its pro-duce is also a great deal on sea food processing in this country. The texture of 'Gul-bi', however, have often appeared to be a delicate factor for the quality of the product. The loss or dislocation of fat in the tissue of the fish resulted by salting and drying is believed to profoundly relate to the texture of product. In this paper, the tissue of yellow corvenia and movement of fat were microscopically observed before salting, immediately after salting, and after drying and the results observed in the tissues dry salted, brine salted, and brine salted with the addition of BHA were compared. The cross section of yellow corvenia muscle showed that a distinctive border by connective tissue between white and red muscle could not be seen in general, and red muscle was surrounded by hypodermic fatty tissues. In the tissue of fresh yellow corvenia, the fat was mainly distributed in hypodermic fat layer which located under the corium while rarely distributed in white muscle. It was found that some parts of the fat in the tissue were permeated into intermuscular tissue passing through the connective tissues during salting. The result Was the same in both dry-salting and brine-salting tissue. However, the fat translocated into intermuscular tissues disappeared during drying process in the salted without BHA tissues whereas in BHA added tissue. This result suggested that BHA may take a role of multiple effect in translocation of fat in tissues as well as in retarding oxidation. In an advanced stage of salted and dehydration, the muscle fibers were ajoined together and then limits between muscle fibers already became indistinguishable. And the migrated fat into intermuscular tissue aggregated around the connective tissue and are apt to gradually to flow out from the muscular system through these tissues.

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A Geophysical Study for the Subsurface Structure of the Bomun Basin (보문분지 구조파악을 위한 지구물리탐사)

  • Suh, Man-Cheol;Yun, Hye-Su
    • Journal of the Korean Geophysical Society
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    • v.3 no.1
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    • pp.67-74
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    • 2000
  • Subsurface structure of the Bomun basin was studied along three survey tracks of Line-1, Line-2, and Line-3 using geomagnetic, radioactive, and seismic refraction methods. Abrupt changes found at 2.55 km west and 1.6 km east in the profile of magnetic anomaly along Line-1 are correlated with geologic boundary of the basin. Profiles of radioactive intensity also represent abrupt changes at 2.55 km west of Line-1 and at 1.9 km of Line-2. Cretaceous basement rock has relatively high magnetic anomaly of $200\;{\sim}\;500\;nT$ while sedimentary rocks of the Bomun basin have relatively low magnetic anomaly of $-100\;{\sim}\;+100\;nT$. Radioactive intensity also represents charateristic differences between Cretaceous basement and sedimentary rocks of the Bomun basin. Rocks of Cretaceous basement have lower radioactive intensity than the rocks of the Bomun basin. Magnetic anomaly of of the Bomun basin represents lowest anomaly in western part and increases gradullay toward east. This phenomenon is interpreted as a half graben structure dipping westward. Black shale known by previous studies near the western boundary has high magnetic anomalies and low radioactive intensity. This phenomenon provide a possibility of volcanic rock rather than black shale near the western boundary of the basin along Line-1. Sedimentary layers having velocities of 455 m/s, 1904 m/s, and 2662 m/s are developed to have westward dipping of $2.3^{\circ}$ in the central area of the Bomun basin. The result is consistent with a half-graben model dipping westward which were derieved from magnetic anomaly data.

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Ethnic Conflicts of the Have-nots: Emergent Hispanic Ethnicity (미국 빈민층 민족집단간의 갈등: 남미계 이민집단의 등장을 중심으로)

  • Kwon, Sang-Cheol
    • Journal of the Korean Geographical Society
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    • v.31 no.4
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    • pp.672-684
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    • 1996
  • This paper explores the inter-ethnic conflicts between Blocks and Hispanics focusing on the emergent Hispanic ethnictity that reveals situational character in the US contexts. In the US census categories, major groups are indetified by race and ethnicity in which the Hispanic orgin is a category based on their common language while diverse in nationality. The census defined Hispanic category extends conveniently to acquiesce Affirmative Action and other government resource distribution. Internally, Hispanics have established numerous organizations to coalesce and assure their interests. The achieved dual language program and jurisdictional revision to represent language minority work as leverages to their cohesiveness. Under diminishing public resources and welfare payment, it is more difficult sharing burdens than benefits between minority groups. Block are not comfortable with the benefits Hispanics receive form the civil rights achievement without having had to struggle for it. The ethnic conflicts of the have-nots have become a new ethnic phenomenon attributable to the emergent Hispanic ethnicity.

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Psychological Essentialism and Category Representation (심리적 본질주의와 범주표상)

  • Kim, ShinWoo;Jo, Jun-Hyoung;Li, Hyung-Chul O.
    • Korean Journal of Cognitive Science
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    • v.32 no.2
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    • pp.55-73
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    • 2021
  • Psychological essentialism states that people believe some categories to have hidden and defining essential features which cause other features of the category (Gelman, 2003; Hirschfeld, 1996; Medin & Ortony, 1989). Essentialist belief on categories questions the Roschian argument (Rosch, 1973, 1978) that categories merely consist of clusters of correlated features. Unlike family resemblance categories, essentialized categories are likely to have clear between-category boundaries and high within-category coherence (Gelman, 2003; Prentice & Miller, 2007). Two experiments were conducted to test the effects of essentialist belief on category representation (i.e., between-category boundary, within-category coherence). Participants learned family resemblance and essentialized categories in their assigned conditions and then performed categorization task (Expt. 1) and frequency estimation task of category exemplars (Expt. 2). The results showed, in essentialized categories, both boundary intensification and greater category coherence. Theses results are likely to have arisen due to increased cue and category validity in essentialized categories and suggest that essentialist belief influences macroscopic representation of category structure.

Aspiration Cytology of Insular Carcinoma of Thyroid - A Case Report - (갑상선 미분화 "도암종"의 세침흡인 세포학적 소견 - 1례 보고 -)

  • Yang, Young-Il;Kim, Chan-Hawn;Khang, Shin-Kwang
    • The Korean Journal of Cytopathology
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    • v.5 no.1
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    • pp.46-51
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    • 1994
  • Fine needle aspiration cytologic features of a case of insular carcinoma of the thyroid in a 23-year-old woman who presented a palpable neck mass is described. The aspirate showed cellular smear arranged in trabeculae, solid or loose clusters, and microfillicles in necrotic background. The tumor cells had uniform, small round, hyperchromatic nuclei. The chromatin was finely granular, and nuclear membrane was smooth. Nucleoli were not discernible. Nuclear pleomorphism was minimal. The cytoplasm was usually scanty, pale, poorly outlined, and almostly amphophilic. Sometimes paranuclear cytoplasmic vacuoles were noted. final diagnosis was confirmed by total thyroidectomy as insular carcinoma.

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