• Title/Summary/Keyword: 사이중심도

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Unfolding In Virtual Colonoscopy Using Control Points of the Center Path (중심 경로의 제어점을 이용한 가상 대장 내시경에서의 펼친 영상 재구성)

  • Won, Jun-Yeon;Shin, Byeong-Seok
    • Journal of the Korea Computer Graphics Society
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    • v.10 no.1
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    • pp.23-28
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    • 2004
  • 가상 내시경의 주된 목적은 체내 장기의 3차원적 구조를 가시화하여 광학 내시경을 모사하는데 있다. 가상 내시경 기법 중 펼친 영상 가시화 기법(unfold rendering)은 장기의 내부 구조와 병변의 유무를 쉽게 판단할 수 있도록 하는 장점이 있다. 가장 일반적으로 사용 하는 중심 경로 기반의 광선 투사법은 곡률이 급격하게 변하는 경우 광선들이 교차하여 병변이 두개로 나타나 문제가 발생할 수 있다. 이를 해결하기위해 광선들이 겹치지 않도록 보장하는 여러 기법들이 발표되었지만 계산량이 많은 단점을 가지고 있다. 본 논문에서는 경로의 제어점을 이용하여 적은 비용으로 펼친 영상을 재구성하는 방법을 제안한다. 우선 모든 중심 경로의 제어점에서 경로에 수직인 절단면을 찾는다. 이때 제어점으로부터 방사상으로 광션을 투사하여 절단면과 만나는 장기 내 벽의 위치를 파악한다. 절단면간의 교차 검사 및 보정을 통해 절단연들이 서로 교차하지 않도록 조정한다. 제어점들 사이의 샘플점들은 앞서 구한 임의의 제어점에서 광선이 투사된 위치로 부터 다음 제어점에서 투사된 위치를 잇는 선분을 보간하여 광선 투사 위치를 결정하게 된다. 마지막으로 계산된 방향 따라 광선을 투사하여 영상을 생성한다.

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Analysis on the Visitors' Pattern of the University Webpages (대학 웹페이지 방문자 패턴분석)

  • Jeon, Mihyeon;Kwon, Hyejung;Hwang, Jahee;Kim, Gyu-Tae;Cho, HyungJun
    • KIPS Transactions on Software and Data Engineering
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    • v.7 no.4
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    • pp.153-158
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    • 2018
  • The visitors' patterns of the homepages in university were classified and analyzed with the network analysis based on the hyperlinks. The numbers of visits to English web-pages were proportional to those of Korean with much less counts. The larger count of visits was confirmed for the case of colleges than the departments, showing the upper boundary of visits from the plot with the Betweenness centrality normalized by the degree. For the better visibility, well-designed hyperlinks with the proper public relations were suggested based on the quantitative analysis of visitors' count.

Secondary bars in barred galaxies

  • Kang, Wongi;Lee, Yun hee;Park, Myeong gu
    • The Bulletin of The Korean Astronomical Society
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    • v.43 no.2
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    • pp.54.2-54.2
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    • 2018
  • 나선 은하의 60%의 은하들은 그 중심에 막대를 가지고 있다고 알려져 있다. 그리고 막대 은하들 중 다시 30%의 은하들이 그 중심에 두 번째 막대를 가지고 있다는 보고들이 있었다. 우리는 SDSS/DR7을 기반으로 z < 0.01 안에 은하들을 눈으로 분류한 Ann et al. (2015) 카탈로그 중 Lee et al. (2018, submitted)에서 사용된 Mr = -15.2 보다 밝고, $60^{\circ}$이하로 기울어진 막대 은하 553개를 이용하여 막대 안에 있는 두 번째 막대를 찾고자 했다. 우리는 ellipse fitting profile을 조사하여 58개의 은하들에서 그 중심에 기존 막대의 형태를 따르지 않고 장축이 어긋나 있으며, 타원율에 변화를 보이는 두 번째 막대의 흔적을 찾았다. 그 중 9개의 은하에서 색지도, 등광도 그리고 unsharp image 등에서 두 번째 막대를 확인했다. 이것은 이전의 30개 내외의 은하들를 대상으로 했던 연구들에서 확인된 것에 비해 매우 적은 비율이라 할 수 있다. 9개의 두 번째 막대들 중 5개는 강한 막대 (SB)안에서 발달해 있고, 4개는 약한 막대 (SAB) 안에 발달해 있어, 수치적으로는 두 번째 막대의 강한 막대와 약한 막대 사이의 선호도 차이는 없어 보인다. 하지만, 약한 막대 안에 발달해 있는 두 번째 막대들은 막대와 서로 다른 방향의 타원 구조만 보이는 반면, 강한 막대 안에 발달해 있는 두번째 막대들은 nuclear ring, nuclear arm등과 함께 더욱 발달된 모습을 보인다. 또한 두 번째 막대를 가지고 있는 8개의 은하 모두에서 주 막대를 따라 중심부로 길게 늘어서 먼지 띠가 뚜렷하게 보이고, 허블 분류에서는 Sab(T=3), Sb (T=4)에 주로 분포해있다.

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A Study of Formalized Presentation of Worm based on time-based Behavioral sequences (시간적인 행동 패턴을 고려한 웜의 정형 표현 기법 연구)

  • Lee Min-Soo;Shon Tae-Shik;Cho Sang-Hyun;Kim Dong-Soo;Seo Jung-Taek;Sohn Ki-Wook;Moon Jong-Sub
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.16 no.3
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    • pp.53-64
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    • 2006
  • Worm analysis report currently produced by anti-virus companies closely resemble those of virus report and do not properly characterize the specific attributes of worms. In this paper, we propose formalized presentation method based on time-based behavioral sequences to more accurately characterize worms. we define a format based on the behavior and communication patterns that occur between an infected host and a target host. we also propose a method for presently worm analysis data with that format. We also compare our framework with analysis data provided by Symantec.

Intermediate Node Mobility Management Technique by Real-Time Monitoring in CCN Environment (CCN 환경에서 실시간 모니터링에 의한 중간노드 이동성 관리 기법)

  • Ko, Seung-Beom;Kwon, Tae-Wook
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.5
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    • pp.783-790
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    • 2022
  • The development of SNS and video platforms provided an opportunity to explode the activation of content production and consumption. However, in the legacy system, due to the host-based location-oriented data transmission, there are inherent limitations in efficient operation and management. As an alternative to this, a Contents Centric Network (CCN) was studied. In this paper, when intermediate nodes located between the information provider and the information requester between the real-time streaming services in the CCN environment move or restrict their use, failure through monitoring of wireless reception strength to solve problems like disconnection of transmission quality at the information consumer. We propose a stable intermediate node management mechanism through active response before occurrence.

An Analysis on the Relation between Network Structure and Research Performance of Joint Researches in Accordance with the Matter of Supporting Research Funds: Focusing on the CT Area (연구비 지원 여부에 따른 공동연구의 네트워크구조와 연구성과 관계 분석: CT분야를 중심으로)

  • Kim, Minki;Kim, Donghyun;Cho, Keuntae
    • Journal of Technology Innovation
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    • v.23 no.4
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    • pp.63-87
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    • 2015
  • As the important factors to improve research performance, the researchers' capacity and the input of resources like research funds have been pointed out. As joint researches are recently vitalized, however, the scientific knowledge is produced by forming continuous mutual relations through the structural characteristics between researchers. Since the support of research funds becomes a foothold to perform researches as multiple institutions cooperate with each other, it can be considered to have influence on research performance. In other words, it can be estimated that the support of research funds has influence on research performance by generating differences in the connecting structure of joint researches. In the results of analyzing the relation between network structure and research performance in accordance with the matter of supporting research funds, targeting the joint research theses in the culture technology(CT) area for five years from 2009 to 2013 in SCIE DB, when multiple research institutes are connected to each other, the number of thesis is increased. When the betweenness centrality is increased, the number of thesis is decreased. Also, the matter of supporting research funds has influence on network structure and research performance.

Classroom Discourse Analysis between Teacher and Students in High School Statistics Class - Focused on Mehan's Theory - (고등학교 통계 수업 시간에 나타난 교사-학생 간 수업담화 분석 - Mehan의 이론을 중심으로 -)

  • Lee, Yoon-Kyung;Cho, Cheong Soo
    • School Mathematics
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    • v.17 no.2
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    • pp.203-222
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    • 2015
  • This study analyzed the classroom discourse between teacher and students based on the Mehan(1979a)'s theory to examine the characteristics of the classroom discourse between teacher and students in high school statistics class. The results of this study on the structure of class showed that the statistics class in this study adopted knowledge transmission-oriented teacher-led class in which the framework of introductiondevelopment- arrangement, which is Mehan's basic 3 stages, is clearly represented. The results of examining I-R-E sequence showed that $I_T-R_T$ structure, in which the teacher asks questions and the teacher talks about the answer, frequently appeared. And the statistics class in this study was monological class in which students hardly participated. Through these results of this study, it was found that teacher should form the statistical context, in which students can participate in discourse, and build discourse learning community and induce argumentational discourse through metaprocess elicitation.

A Study on distribution and change of NDVI with Land-Cover change in City of Sungnam (토지피복 변화에 따른 식생지수(NDVI)분포 및 변화에 관한 연구: 성남시를 중심으로)

  • 성효현;박옥준
    • Spatial Information Research
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    • v.8 no.2
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    • pp.275-288
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    • 2000
  • The purpose of this study is to analyze relationship between the NDVI change pattern and landcover change pattern in the City of Sungnam during 1985 and 1996. The results of this study are as follows; (1) NDVI of the level 6 and 7 is decreased and the level 5 is increased in the area where Forst area changed to the other land cover during 1985 and 1996. (2) In the area where Agricultural-Pasture changed to forest, NDVI level became higher certainly during that time. But in the area where there has been changed from Agricultural-Pasture to Urban or built-up, Agricultural-Pasture to Barren land, the level of NDVI is decreased. (3) In the Urban or built-up to other land, or built-up the level of NDVI is increased. (4) In the area where Barren land changed to other land cover, the level of NDVI is increased.

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A study on the expression of space and time by match cut in the image media -focusing on the movie, Bram Stoker's Dracula (1992)- (영상미디어에서 매치 컷을 통한 시·공간 표현 연구 -영화<드라큘라>(1992)를 중심으로-)

  • Lim, Yong-Seob
    • Journal of Digital Convergence
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    • v.16 no.5
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    • pp.419-424
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    • 2018
  • Match cut is the montage technique that is widely used in the image media. This technique is versatile to generate the receivers a variety of meanings. In this article, the match cut shorts applied in the movie, Bram Stoker's Dracula, were analyzed based on the meanings occurred between the shorts. In addition, the analysis methods were based on the philosophical issues of Gilles Deleuze which had been analyzed focusing on the generation competency. Also, Francis Bacon's paintings, 'painting' (1946) and 'self-portrait' (1969) demonstrating similar meanings were compared to assist understanding. Upon the analyses of these two media, the meanings of 'becoming' that had the feature of nomadism between the shorts and occurred in the process of combined generation were analyzed. Therefore, match cut occurred in the image media was found to function to the receivers in a variety of ways and the degree of its utilization was not limited upon this analysis.

Globalization, Corporate Social Responsibility and Corporate Financial Performance: Evidence from Korea (글로벌화, CSR 그리고 기업의 재무적 성과: 한국기업을 중심으로)

  • Byun, Sun-Young;Nam, Hyun-Jung
    • Management & Information Systems Review
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    • v.36 no.1
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    • pp.161-180
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    • 2017
  • This article studies the theory of corporate social responsibility; CSR. By examining the flow of CSR in the Korean market and empirical testing, investigates the relationship between CSR and corporation financial performance (CFP) in Korean enterprises. This paper places emphasis on the change in CSR as a result of globalization and explores the influence of CSR on CFP by using data from 2008 to 2014 of 528 Korean Firms, 1583 time series observations. We found that globalization had a positive influence on Korean CFP and that CSR activities derived from globalization exert a positive influence on CFP. Our findings show that CSR can strengthen the positive influence of globalization on CFP, and the Korean corporations' changing perception of CSR.

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