• Title/Summary/Keyword: 바람 데이터

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Application of ERA-Interim Reanalysis Data for Onshore and Offshore Wind Resource Assessment (육·해상 풍력자원평가를 위한 ERA-Interim 재해석 데이터의 적용)

  • Byun, Jong-Ki;Ko, Kyung-Nam
    • Journal of the Korean Solar Energy Society
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    • v.37 no.2
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    • pp.1-11
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    • 2017
  • The investigation on reliability of ERA-Interim reanalysis wind data was conducted using wind data from the five met masts measured at inland and coastal areas, Jeju island. Shinchang, Handong, Udo, Susan and Cheongsoo sites were chosen for the met mast location. ERA-Interim reanalysis data at onshore and offshore twenty points over Jeju Island were analyzed for creating Wind Statistics using WindPRO software. Reliability of ERA-Interim reanalysis wind data was assessed by comparing the statistics from the met mast wind data with those predicted at the interest point using the Wind Statistics. The relative errors were calculated for annual average wind speed and annual energy production. In addition, the trend of the error was analyzed with distance from met mast. As a result, ERA-Interim reanalysis wind data was more suitable for offshore wind resource assessment than onshore.

A Study on the Extraction of the Matsucoccus Thunbergianae Miller et Park Damaged Area from Satellite Image Data (인공위성 화상데이터를 이용한 솔껍질깍지벌레 피해지역의 추출기법에 관한 연구)

  • 안기원;이효성;서두천
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.15 no.2
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    • pp.287-298
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    • 1997
  • The main object of this study was to prove the effectiveness of satellite image data for extraction of the Matsucoccus Thenbergianae Miller ビt Park damaged area. The effectiveness of extraction of damaged area was improved by using the BRCT(Backwards radiance correction transformation) with DEM for normalization of topographic effects. The surface analysis of the extracted damaged area was revealed that the damage was started at south-west slope with the aspect of 7 to 18 degrees, and 50% to 70% of the highest altitude mountains. The direction of damage attached by the Matsucoccus Thunbergianae Miller et Park was able to predict through the analysis of periodical of years' images

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Low-Latency Median Filter Architecture for High-Speed Image Signal Processor (초고속 영상 신호 처리기를 위한 낮은 잠복지연시간을 가지는 미디언 필터 구조)

  • Park, Hyun Sang
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2011.11a
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    • pp.113-116
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    • 2011
  • 고해상도 이미지 센서를 장착한 고가의 모바일 제품들이 확산되면서 중간값 필터에 기반을 둔 잡음 제거 필터의 필요성이 증가하고 있다. 이는 초박형 카메라에 내장된 이미지 센서의 물리적인 수광부 면적이 줄어듦에 따라 이미지 센서의 SNR이 떨어지기 때문이다. 게다가 영상의 해상도가 매우 높기 때문에 잡음제거 필터는 초고속으로 동작해야 한다. 따라서 잡음 제거 필터의 핵심 기능인 중간값 필터는 높은 동작주파수에서도 효과적으로 동작해야 한다. 초고속으로 동작하는 필터를 하드웨어로 구현하려면 입출력 간의 물리적 지연시간을 클럭의 주기 단위로 나누어서, 시분할하여 순차적으로 처리하는 파이프라인 구조를 가져야 한다. 파이프라인 단계는 많은 비용이 소모되는 레지스터로 구현되므로 파이프라인 단계를 줄이는 것이 바람직하다. 본 논문에서는 입력부터 출력까지의 물리적 지연시간이 데이터의 수에 비례하는 기존의 중간값 필터와 달리, 데이터 수의 로그값에 비례하는 중간값 필터의 구조를 제안한다. 제안한 중간값 필터는 서로 다른 값을 가지는 데이터 집합에서의 중간값은 자신보다 큰 원소의 수와, 작은 원소의 수가 같다는 사실을 이용하며, 버블 정렬 구조에 기반을 둔 중간값 필터에 비해서 같은 동작주파수에서의 게이트 수가 25.3% 줄어든다. 중간값 필터는 잡음제거나 위색제거 등에서도 널리 사용되고 있으므로, 제안한 구조의 중간값 필터는 초고속으로 동작하는 이미지 신호 처리기의 효과적인 구현에 적합하다.

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Representation and Management of e-Learning Object Metadata Using ebXML (ebXML 등록저장소를 이용한 이러닝 객체 메타데이터의 표현과 관리)

  • Kim, Hyoung-Do
    • The Journal of the Korea Contents Association
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    • v.6 no.11
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    • pp.249-259
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    • 2006
  • E-learning objects should be appropriately described and classified using standard metadata for facilitating the processes of e-learning resource description, discovery and reuse. These metadata need to be published in a registry to reduce duplication of effort and enhance semantic interoperability. This paper describes how standard ebXML registries can be used for annotating, storing, discovering and retrieving e-learning object metadata. For semantic annotation of e-learning objects, IEEE LOM is adopted as the metadata ontology. In order to support the e-learning metadata ontology in interoperable ebXML registries, a mapping scheme between LOM and ebXML information model is proposed. The usefulness of standard ebXML registries for sharing e-learning metadata is demonstrated by prototyping an e-learning registry called ebRR4LOM based on the scheme.

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Spatial Index based on Main Memory for Web CIS (Web GIS를 위한 주기억 장치 기반 공간 색인)

  • 김진덕;진교홍
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.10a
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    • pp.191-194
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    • 2001
  • The availability of the inexpensive, large main memories coupled with the demand for faster response time are bringing a new perspective to database technology. The Web GIS used by u unspecified number of general public in the internet needs high speed response time and frequent data retrieval for spatial analysis rather than data update. Therefore, it is appropriate to use main memory as a underlying storage structures for the Web GIS data. In this paper, we propose a data representation method based on relative coordinates and the size of the MBR. The method is able to compress the spatial data widely used in the Web GIS into smaller volume of memory. We also propose a memory resident spatial index with simple mechanism for processing point and region queries. The performance test shows that the index is suitable for managing the skewed data in terms of the size of the index and the number of the MBR intersection check operations.

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Problem Analysis and Recommendations of CPU Contents in Korean Middle School Informatics Textbooks (중학교 정보 교과서에 제시된 중앙처리장치 내용 문제점 분석 및 개선 방안)

  • Lee, Sangwook;Suh, Taeweon
    • KIPS Transactions on Computer and Communication Systems
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    • v.2 no.4
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    • pp.143-150
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    • 2013
  • The School Curriculum amend in 2007 mandates the contents from which students can learn the principles and concepts of computer science. Computer Science is one of the most rapidly changing subjects, and the Informatics textbook should accurately explain the basic principles and concepts based on the latest technology. However, we found that the middle school textbooks in circulation lack accuracy and consistency in describing CPU. This paper attempted to discover the root-cause of the fallacy and suggest timely and appropriate explanation based on the historical and technical analysis. According to our study, it is appropriate to state that CPU is composed of datapath and control unit. The Datapath performs operations on data and holds data temporarily, and it is composed of the hardware components such as memory, register, ALU and adder. The Control unit decides the operation types of datapath elements, main memory and I/O devices. Nevertheless, considering the technological literacy of middle school students, we suggest the terms, 'arithmetic part' and 'control part' instead of datapath and control unit.

Privacy-Preserving K-means Clustering using Homomorphic Encryption in a Multiple Clients Environment (다중 클라이언트 환경에서 동형 암호를 이용한 프라이버시 보장형 K-평균 클러스터링)

  • Kwon, Hee-Yong;Im, Jong-Hyuk;Lee, Mun-Kyu
    • The Journal of Korean Institute of Next Generation Computing
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    • v.15 no.4
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    • pp.7-17
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    • 2019
  • Machine learning is one of the most accurate techniques to predict and analyze various phenomena. K-means clustering is a kind of machine learning technique that classifies given data into clusters of similar data. Because it is desirable to perform an analysis based on a lot of data for better performance, K-means clustering can be performed in a model with a server that calculates the centroids of the clusters, and a number of clients that provide data to server. However, this model has the problem that if the clients' data are associated with private information, the server can infringe clients' privacy. In this paper, to solve this problem in a model with a number of clients, we propose a privacy-preserving K-means clustering method that can perform machine learning, concealing private information using homomorphic encryption.

A Study on Research Data Management Methods for Government-funded Research Institutes in the Field of Science and Technology (과학기술분야 정부출연연구기관 연구데이터 관리 방안 연구)

  • Na-eun Han;Jung-Ho Um;Hyung-Jun Yim
    • Journal of the Korean Society for Library and Information Science
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    • v.58 no.2
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    • pp.151-175
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    • 2024
  • This study analyzes the current status of research data management at NST-affiliated government-funded research institutes for the purpose of promoting the sharing and use of research data, and based on this, suggests methods for establishing a research data sharing and management system. The survey on the status of research data management was conducted twice in 2022 and 2023 for a total of 20 research institutes. In addition, difficulties and areas that need to be improved in the management and sharing of research data were identified, and based on this, methods for establishing a research data sharing and management system were proposed by dividing them into policy aspects, system aspects, and linkage system construction aspects. In order to establish a research data sharing system, it would be desirable to prepare a policy basis and present contents such as the definition of research data, scope of application, contents of management, utilization method, and leading institutes. In addition, for systematic and unified research data management, it would be recommended that each institute will establish and manage a repository and management system. By linking this with DataON, the national research data platform, and providing one-stop services, the accessibility and usability of data will be improved.

A Study on the Organizational Changes in Technical Service of Korean University Libraries (국내 대학도서관 정리부서 현황과 조직 변화에 대한 인식 연구)

  • Lee, Ji-Won
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.25 no.1
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    • pp.193-215
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    • 2014
  • This study investigated organizational changes in technical services of university libraries and analysed librarians' perception on the changes of technical service department by the survey to 32 technical service librarians. It also identified several factors that have changed work environment of technical departments such as the shared cataloging and outsourcing, and electronic resources in various formats and creation of metadata for these resources. Most librarians agreed that university libraries have to foster technical librarians' professioanal development to cope with emerging changes of technical services. They also recognized that the integration of traditional cataloging and metadata management is an important issue of orgranizational changes. Contrary to librarians' perception, technical service librarians were not fully awared of the procedure of metadata related works in other departments. Furthermore metadata creation and management were also conducted in several departments of libraries without proper control.

Candidate Marker Identification from Gene Expression Data with Attribute Value Discretization and Negation (속성값 이산화 및 부정값 허용을 하는 의사결정트리 기반의 유전자 발현 데이터의 마커 후보 식별)

  • Lee, Kyung-Mi;Lee, Keon-Myung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.21 no.5
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    • pp.575-580
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    • 2011
  • With the increasing expectation on personalized medicine, it is getting importance to analyze medical information in molecular biology perspective. Gene expression data are one of representative ones to show the microscopic phenomena of biological activities. In gene expression data analysis, one of major concerns is to identify markers which can be used to predict disease occurrence, progression or recurrence in the molecular level. Existing markers candidate identification methods mainly depend on statistical hypothesis test methods. This paper proposes a search method based decision tree induction to identify candidate markers which consist of multiple genes. The propose method discretizes numeric expression level into three categorical values and allows candidate markers' genes to be expressed by their negation as well as categorical values. It is desirable to have some number of genes to be included in markers. Hence the method is devised to try to find candidate markers with restricted number of genes.