• Title/Summary/Keyword: 계층적 시각화

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Image coding Using Modified Block Zerotree (수정된 블록 제로트리를 이용한 영상 부호화)

  • 권진수;유지상
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.4B
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    • pp.471-478
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    • 2001
  • 웨이블릿 변환은 영상을 위치 정보와 주파수 정보를 가지고 표현함으로서 다른 변환 방식과는 큰 차이를 보여준다. 웨이블릿 변환된 2-D 영상은 인간의 시각 체계(Human Visual System)에 적정한 양자화 및 부호화를 위한 계층적 구조를 제공한다. 인간의 시각이 민감하게 감지하는 성분은 정확하게 부호화하고 다른 성분은 적절한 정보의 손실을 적용하는 원리를 이상적으로 적용할 수 있다. 이런 웨이블릿 변환의 통계적 특성을 이용한 제로트리(zerotree) 부호화 기법은 영상 전체에서 의미 있는 계수를 선별하여 약속된 우선 순서대로 부호화함으로써 매입파일(embedded file)을 생성한다. 본 논문에서는 Shspiro 가 제안한 EZW(embedded Zerotree wavelets) 알고리즘을 개선하여 화소 단위가 아닌 블록 단위로 부호화 함으로서 좀더 나은 성능을 가진 알고리즘을 제안하였다.

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Extracting Logical Structure from Web Documents (웹 문서로부터 논리적 구조 추출)

  • Lee Min-Hyung;Lee Kyong-Ho
    • Journal of Korea Multimedia Society
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    • v.7 no.10
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    • pp.1354-1369
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    • 2004
  • This paper presents a logical structure analysis method which transforms Web documents into XML ones. The proposed method consists of three phases: visual grouping, element identification, and logical grouping. To produce a logical structure more accurately, the proposed method defines a document model that is able to describe logical structure information of topic-specific document class. Since the proposed method is based on a visual structure from the visual grouping phase as well as a document model that describes logical structure information of a document type, it supports sophisticated structure analysis. Experimental results with HTML documents from the Web show that the method has performed logical structure analysis successfully compared with previous works. Particularly, the method generates XML documents as the result of structure analysis, so that it enhances the reusability of documents.

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A Study on Implementation and Applying Relationship Ontology System Using RDF/OWL Object Property (RDF/OWL의 객체속성을 이용한 관계온톨로지 시스템 구축과 활용에 관한 연구)

  • Kang, Hyen-Min
    • Journal of the Korean Society for information Management
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    • v.27 no.4
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    • pp.219-237
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    • 2010
  • This study proposes a 'Bibliographic Universe Relationship Vocabulary'(burv) using the RDF/OWL Object Property under the SPO predicate logic according to the relationship type among all entities of bibliographic universe and implemented a 'relationship ontology system' to establish a new cataloging business domain called 'Relationship Description Cataloging' based on the ontology.

An Embedded Image Coding Scheme by Detecting Significant Wavelet Coefficients (중요 웨이브렛 계수 검출에 의한 임베디드 영상 부호화 기법)

  • Park, Jeong-Ho;Choi, Jae-Ho;Kwak, Hoon-Sung
    • Journal of the Korean Institute of Telematics and Electronics S
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    • v.36S no.8
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    • pp.48-54
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    • 1999
  • A new method for wavelet embedded image coding is presented extending the bases of the Shapiro's algorithm by incorporating edge detection, zerotree scheme, and classified VQ(CVQ). Generally edges in the image are regarded an visually important components and the previous literatures have proved that significant coefficients in wavelet transform domain correspond to the edges in spatial domain. Hence, by identifying the edge elements, the significant coefficient can be easily detected in wavelet domain without investigating descendant coefficients across layer. Hierarchical trees for the significant components are organized, and then CVQ method is applied to these trees. Since the significant information has higher priority in transmission, the simulation shows that our coder provides a superior performance over the conventional method and can be successfully applied to the application areas that require of progressive transmission.

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An Analysis of the 3D Spatial Distribution of Flow rate and Water Quality Convergence Monitoring Results in Rivers (하천에서의 수리·수질 복합 모니터링 결과의 3차원 공간분포 해석연구)

  • Lee, Chang Hyun;Kim, Kyung Dong;Ryu, Si Wan;Kim, Dong Su;Kim, Young Do
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.18-18
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    • 2022
  • 하천 합류부에 있어 수체의 혼합양상을 분석은 고해상도의 자료가 필요하다. 반면에 수질환경 문제와 기존 모니터링 시스템이 고정된 측정 방식으로 이루어지기 때문에 하천 전체의 정보는 저해상도의 결과값은 나타낸다. 또한, 많은 수중 환경 문제가 1차원에서 3차원에 걸쳐 있지만, 대부분의 관측 시스템은 1차원에 머물러 있음을 확인할 수 있다. 이러한 문제를 해결하기 위해서는 보다 발전된 관찰 및 계측이 필요하다. 그에 따른 고해상도의 측정 자료를 얻기 위해서는 측정자가부담을 많이 가지며, 측정할 수 있는 영역이나 시간적으로 제한적이다. 해상도는 낮추되 광범위한 데이터를 취득하기 위해서는 적절한 보간법이 선정되어야 한다. 관련 논문을 검토한 결과, 측정 결과에 따른 2차원 횡단면 분포의 내용이 지배적이었고, 3차원 매핑 및 3차원 분석을 통한 수리학적 정보 획득에 관한 연구는 부족한 실정이였다. 특히 3차원 하천 수질 농도의 연구가 불충분했다. 그에 따라 저해상도 측정결과에서의 예측과 보간법에 대한 시각화를 통해 하천의 전체적인 수리·수질정보를 표기하였다. 각각의 보간법을 비교함으로써 하천 매핑에 있어 IDW, Natual Neighbor, Kriging 기법을 적용하여 시각화된 자료와 정량적 평가를 통해 하천매핑의 정밀성을 향상시켰다. 이를 통해 3차원화된 공간보간 자료를 이용한 하천합류부의 혼합양상을 해석하였다. 3차원 데이터를 활용하는 방법으로 측정 및 모니터링 기술의 중요한 데이터로 활용되며, 이러한 데이터는 유해물질 저감 기술 및 평가 예측 기술의 기초 데이터로 활용되고 있다. 유해화학물질 추정, 호수의 고위험 조류군 계층분석 등 다양한 수생건강 진단기술을 활용할 수 있다.

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A Study on the Pilot Application of Disaster Information Delivery and Evacuation Support System for the Vulnerable Groups (안전취약계층 대상 재난정보 전달 및 대피지원 체계 시범적용 연구)

  • Jung Tae-Ho;Lee, Han-Jun
    • Proceedings of the Korean Society of Disaster Information Conference
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    • 2022.10a
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    • pp.139-140
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    • 2022
  • 본 연구는 재난발생 시 현장 상황 판단 및 대응 능력이 현저히 떨어지는 안전취약계층 중 장애인과 노인이 재난정보를 받고 안전하게 대피·대응할 수 있도록 지원하는 시스템의 시범적용에 대한 것이다. 재난정보 전달 및 대피지원 시스템은 재난에 취약한 장애인과 노인이 재난상황에서 각각의 취약 특성을 고려하여 재난 위기상황에 대응하도록 설계 하였으며, 실내 위치측정에 관한 공간정보 표준 및 데이터 구축과 개발한 시스템을 설치하고 구현할 수 있는 실내 공간을 선정하여 시범적으로 적용하였다. 재난정보 및 대피지원 시스템의 시범적용을 위해 선정된 시설의 실내 공간정보 구축 및 현행화를 통해 실내 대피경로를 구축하고, 실제 시범적용을 통해 보완하는 과정을 수행하였다. 장애인·노인 대상 재난정보 전달 및 대피지원 서비스 구축을 위해 실내에서 재난발생 시 재난정보 데이터를 실시간으로 수집하고 스마트폰과 연계할 수 있는 연계 모듈을 개발하였다. 또한 재난정보를 스마트폰에 알릴 수 있는 알람 푸시 모듈, 재난정보 및 대피 안내 모듈과 시각 장애인의 실내 공간 인지를 위한 음성안내 모듈을 개발하였다. 본 연구의 목적은 IoT 기반의 통합관제 기술을 활용하는 서비스 제공을 통해서 정보전달의 사각지대를 해소하고 장애인·노인의 효율적 재난 대응을 위해 맞춤형 재난정보 전달 및 대피지원 서비스를 구축하고 시범적용의 과정을 통해 문제점을 보완하여 최종적으로 재난으로부터 안전취약계층의 안전성을 향상시키는데 목적이 있다.

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Visual Exploration based Approach for Extracting the Interesting Association Rules (유용한 연관 규칙 추출을 위한 시각적 탐색 기반 접근법)

  • Kim, Jun-Woo;Kang, Hyun-Kyung
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.9
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    • pp.177-187
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    • 2013
  • Association rule mining is a popular data mining technique with a wide range of application domains, and aims to extract the cause-and-effect relations between the discrete items included in transaction data. However, analysts sometimes have trouble in interpreting and using the plethora of association rules extracted from a large amount of data. To address this problem, this paper aims to propose a novel approach called HTM for extracting the interesting association rules from given transaction data. The HTM approach consists of three main steps, hierarchical clustering, table-view, and mosaic plot, and each step provides the analysts with appropriate visual representation. For illustration, we applied our approach for analyzing the mass health examination data, and the result of this experiment reveals that the HTM approach help the analysts to find the interesting association rules in more effective way.

Analysis of Research Trends Related to drug Repositioning Based on Machine Learning (머신러닝 기반의 신약 재창출 관련 연구 동향 분석)

  • So Yeon Yoo;Gyoo Gun Lim
    • Information Systems Review
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    • v.24 no.1
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    • pp.21-37
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    • 2022
  • Drug repositioning, one of the methods of developing new drugs, is a useful way to discover new indications by allowing drugs that have already been approved for use in people to be used for other purposes. Recently, with the development of machine learning technology, the case of analyzing vast amounts of biological information and using it to develop new drugs is increasing. The use of machine learning technology to drug repositioning will help quickly find effective treatments. Currently, the world is having a difficult time due to a new disease caused by coronavirus (COVID-19), a severe acute respiratory syndrome. Drug repositioning that repurposes drugsthat have already been clinically approved could be an alternative to therapeutics to treat COVID-19 patients. This study intends to examine research trends in the field of drug repositioning using machine learning techniques. In Pub Med, a total of 4,821 papers were collected with the keyword 'Drug Repositioning'using the web scraping technique. After data preprocessing, frequency analysis, LDA-based topic modeling, random forest classification analysis, and prediction performance evaluation were performed on 4,419 papers. Associated words were analyzed based on the Word2vec model, and after reducing the PCA dimension, K-Means clustered to generate labels, and then the structured organization of the literature was visualized using the t-SNE algorithm. Hierarchical clustering was applied to the LDA results and visualized as a heat map. This study identified the research topics related to drug repositioning, and presented a method to derive and visualize meaningful topics from a large amount of literature using a machine learning algorithm. It is expected that it will help to be used as basic data for establishing research or development strategies in the field of drug repositioning in the future.

Development of Web Based Walking Environmental Measurement System Using the Analytic Hierarchy Process Approach (계층분석법을 이용한 웹 기반 GIS 보행환경측정 시스템 개발)

  • Joo, Yong-Jin;Lee, Soo-Il;Kim, Tae-Ho
    • Journal of Korean Society for Geospatial Information Science
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    • v.19 no.1
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    • pp.3-11
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    • 2011
  • This paper aims to develop a web based GIS system which is able to evaluate and visualize the overall degree (in terms of pleasantness and aesthetics) of pedestrian friendliness of the environment, as well as pedestrians' convenience through a Walkability Indicators that simplify pedestrian environment elements into a quantitative index in accordance with characteristics of pedestrian space. To make this goal come true, we developed and applied Walkability index which can measure the pedestrian environment through reflecting quantitative Indicators based on GIS supplementing the limit of Literature Review. In addition, in order to develop index we utilized AHP(Analytic Hierarchy Process) and we displayed measurement result on study area through web GIS Services. The proposed pedestrian measurement system is expected to be applicable in the visualization of pedestrian movements and the evaluation of convenience levels of pedestrian environment.

Research on the Characteristics of Research Data-related Service in North American University Libraries: Focusing on the Hierarchical Structure of Services, Job Titles, and Job Descriptions (북미 지역 대학도서관의 연구데이터 관련 서비스 특성 연구 - 서비스 간 계층 구조와 직책 및 직책별 직무내용을 중심으로 -)

  • Gyuhwan Kim;Jong-Do Park
    • Journal of the Korean Society for Library and Information Science
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    • v.57 no.2
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    • pp.453-475
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    • 2023
  • This study investigated research data-related services offered by North American university libraries, focusing on service names, hierarchical relationships, job titles of service managers, and job descriptions. The study analyzed the homepages of 50 university libraries and found a clear hierarchical relationship between research data-related service names, indicating a clear structure for these services. The title of 'librarian' was most commonly used for the position in charge of research data-related services, and the job content of this position was found to be quite wide. Other job titles such as 'specialist' and 'analyst' were also used for experts in various research data-related fields. The existence of these job titles was seen as a way for university libraries to strengthen the expertise of their research data-related services. Based on the findings, the authors propose a service composition system for research data-related services in domestic university libraries. This system includes 'research data service' as the highest-level service name, with 'research data management service', 'GIS service', and 'data visualization service' as sub-service names. The authors also suggest that research data-related services should be provided through collaboration between existing university librarians in the early stages of service provision, and that new recruitment of research data-related professionals could be considered gradually.