• 제목/요약/키워드: Network science

검색결과 13,220건 처리시간 0.036초

MOGABA: Monitoring of Gamma-ray Bright AGN with KVN 21-m radio telescopes at 22, 43 and 86GHz

  • 이상성;변도영;백준현;한명희;양지혜;손봉원
    • 천문학회보
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    • 제37권2호
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    • pp.239.2-239.2
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    • 2012
  • We report preliminary results of MOGABA project for monitoring total flux density, linearly polarized flux, and polarization angle at 22, 43 and 86GHz of Gamma-ray bright AGN (Active Galactic Nuclei) with KVN (Korean VLBI Network) 21-m radio telescopes. The project has been conducted in one year since May 2011 with an effective monitoring cycle of 1 week, observing four main objects (3C 454.3, BL Lac, 3C 273, and 3C 279). More objects were included in the source list when they had flared in Gamma-ray. Especially, we included a compact radio source at the Galactic center, SgrA* since Jan. 2012. In this paper, we report the current status of the project and preliminary results for the monitoring observations.

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네트웍 연구의 사회적 접근과 분석이론 (Theoretical Perspective of Social Network Analysis)

  • 유사라
    • 한국문헌정보학회지
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    • 제20권
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    • pp.297-330
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    • 1991
  • The work presents the theoretical background and methodology to network analysis. This approach to information network has been widespread use in many researches of social science. Theoretically based idea of structural analysis of information flow were reviewed and the major perspective and the practical aspects of the analysis were discussed. To show an approach of the methodology to library environment, HISP project which analyzed the network structure of a health information dissemination to a health community was demonstrated.

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다중 네트워크 환경 하에서의 공통 자원 관리 기법 및 네트워크 시뮬레이터 응용 (Common Resource Management and Network Simulator in Heterogeneous Network Environment)

  • 김재훈
    • 경영과학
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    • 제26권1호
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    • pp.113-126
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    • 2009
  • By the newly emerging network access technology, we face the new heterogeneous network environment. Focusing on the co-existence of multiple access network technology and the complex service needs of users, the wireless service operators should present the stable service quality for every user. For this, the service operators should build the new operation framework which combine the pre-established network and newly adopted one. Our problem is finding the optimal heterogeneous network operation framework. We suggest market-based marginal cost function for evaluating the relative value of resource of each network and develop the whole new heterogeneous network operation framework. To test the applicability of developed operation framework, we build large-scale JAVA simulator. By this development, we can easily test the new network environment in practical engineering field.

Emerging Technologies for Sustainable Smart City Network Security: Issues, Challenges, and Countermeasures

  • Jo, Jeong Hoon;Sharma, Pradip Kumar;Sicato, Jose Costa Sapalo;Park, Jong Hyuk
    • Journal of Information Processing Systems
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    • 제15권4호
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    • pp.765-784
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    • 2019
  • The smart city is one of the most promising, prominent, and challenging applications of the Internet of Things (IoT). Smart cities rely on everything connected to each other. This in turn depends heavily on technology. Technology literacy is essential to transform a city into a smart, connected, sustainable, and resilient city where information is not only available but can also be found. The smart city vision combines emerging technologies such as edge computing, blockchain, artificial intelligence, etc. to create a sustainable ecosystem by dramatically reducing latency, bandwidth usage, and power consumption of smart devices running various applications. In this research, we present a comprehensive survey of emerging technologies for a sustainable smart city network. We discuss the requirements and challenges for a sustainable network and the role of heterogeneous integrated technologies in providing smart city solutions. We also discuss different network architectures from a security perspective to create an ecosystem. Finally, we discuss the open issues and challenges of the smart city network and provide suitable recommendations to resolve them.

A Direction Entropy-Based Forwarding Scheme in an Opportunistic Network

  • Jeon, MinSeok;Kim, Sun-Kyum;Yoon, Ji-Hyeun;Lee, JunYeop;Yang, Sung-Bong
    • Journal of Computing Science and Engineering
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    • 제8권3호
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    • pp.173-179
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    • 2014
  • In an opportunistic network, one of the most challenging issues is the equilibrium of the network traffic and transmission delay for forwarding messages. To resolve this problem, we propose a new forwarding scheme, called the direction entropy-based forwarding scheme (DEFS), using the main direction and direction entropy based on the information collected about the directions of the nodes in the network. Since each node sends a message to another node with a different location and less direction entropy, DEFS utilizes those nodes that are more likely to travel to various locations to forward the messages to the destination nodes. Experiments were performed on the network simulator NS-2. The results show that DEFS provides better balance than the typical forwarding schemes, such as Epidemic, PRoPHET, and WAIT.

Behavioral Tendency Analysis towards E-Participation for Voting in Political Elections using Social Web

  • Hussain Saleem;Jamshed Butt;Altaf H. Nizamani;Amin Lalani;Fawwad Alam;Samina Saleem
    • International Journal of Computer Science & Network Security
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    • 제24권2호
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    • pp.189-195
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    • 2024
  • The issue "Exploring Social Media and Other Crucial Success Elements of Attitude towards Politics and Intention for Voting in Pakistan" is a huge study embracing more issues. The politics of Pakistan is basically the politics of semantic groups. Pakistan is a multilingual state more than six languages. There are 245 religious parties in Pakistan, as elaborated by the Daily Times research. The use of social media sites in Pakistan peaked to its maximum after announcement of election schedule by the Election Commission of Pakistan in March 22, 2013. Most of the political parties used it for the recent elections in Pakistan to promote their agenda and attract country's 80 million registered electors. This study was aiming to investigate the role of social media and other critical variables in the attitude towards politics and intention for voting.

사회 연결망 분석 연구동향 및 정보학 분야에서의 활용가능성에 관한 연구 (The Study on the Research Trend of Social Network Analysis and the its Applicability to Information Science)

  • 김성희;장로사
    • 정보관리학회지
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    • 제27권4호
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    • pp.71-87
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    • 2010
  • 본 연구에서는 2000년부터 2009년까지 10년 동안 국내의 학술지에 발표된 사회 연결망 분석과 관련된 논문들을 대상으로 하여 연도별 연구논문 추이와 학문분야별로 구분하여 연구동향을 분석하였다. 연구결과 사회 연결망 분석을 적용한 연구는 총 163편으로서 연차적으로 증가하여 수행되고 있으며, 특히 최근에 많은 연구들이 발표되고 있음을 확인할 수 있었다. 사회연결망 분석은 다양한 분야에서 적용되고 있었고 특히 경영학, 교육학, 행정학 분야 등에서 많이 적용되고 있는 것으로 나타났으며 단독연구보다는 공동연구가 많은 것으로 나타났다. 문헌정보학 분야에서는 웹계량정보학을 포함한 계량정보학 분야에서 최근 들어 상대적으로 많이 사용되고 있는 것으로 나타났다. 이러한 연구결과는 정보학 영역에 있어 사회 연결망 분석의 접목 가능성을 확인하고, 향후 사회 연결망 분석을 정보학에 활용하기 위한 기초자료로 활용할 수 있을 것이다.

ScienceDMZ 기반의 네트워크 구성에서 접근제어정책 적용 (Application of access control policy in ScienceDMZ-based network configuration)

  • 권우창;이재광;김기현
    • 융합보안논문지
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    • 제21권2호
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    • pp.3-10
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    • 2021
  • 데이터 기반의 과학연구가 추세인 요즘 대용량의 데이터 전송은 연구 생산성에 많은 영향을 미친다. 이러한 문제를 해결하기 위해서 대용량 과학 빅데이터를 전송하기 위한 별도의 네트워크 구조가 필요하다. ScienceDMZ는 이러한 과학 빅데이터를 전송하기 위해서 고안된 네트워크 구조이다. 이러한 네트워크 구성에서는 사용자 및 자원에 대한 접근제어정책(ACL, access control list) 수립이 필수적이다. 본 논문에서는 실제 ScienceDMZ 네트워크 구조로 구현된 R&E Together 프로젝트와 네트워크 구조를 설명하고, 안전한 데이터 전송 및 서비스 제공을 위해 접근제어정책을 적용할 사용자 및 서비스를 정의한다. 또한 네트워크 관리자가 전체 네트워크 자원 및 사용자에 대해 일괄적으로 접근제어정책을 적용할 수 있는 방법을 제시하며, 이를 통해 접근제어정책 적용에 대한 자동화를 이룰 수 있었다.