• Title/Summary/Keyword: Large Scale Problem

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Broadcast Scheduling for Wireless Networks Based on Theory of Complex Networks (복잡계 네트워크 기반 무선 네트워크를 위한 브로드캐스트 스케줄링 기법)

  • Park, Jong-Hong;Seo, Sunho;Chung, Jong-Moon
    • Journal of Internet Computing and Services
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    • v.17 no.5
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    • pp.1-8
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    • 2016
  • This paper proposes a novel broadcast scheduling algorithm for wireless large-scale networks based on theory of complex networks. In the proposed algorithm, the network topology is formed based on a scale-free network and the probability of link distribution is analyzed. In this paper, the characteristics of complex systems are analyzed (which are not concerned by the existing broadcast scheduling algorithm techniques) and the optimization of network transmission efficiency and network time delay are provided.

Effect of the Environmental Issue Instruction on the University Student's Environmental Literacy (환경쟁점수업이 대학생의 환경소양 신장에 미치는 영향)

  • Park, Ki-Hak
    • Journal of environmental and Sanitary engineering
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    • v.23 no.4
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    • pp.1-11
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    • 2008
  • The goal of today's environmental education is to enhance the understanding of the serious of environmental problems and the interactions among environment. With this perspectives people need to be aware that environmental education is no longer a liberal arts in university education, but play a vital role within the socio-cultural context. This study was performed to assess the changes in the university student's attitudes and consciousness in real life after the education of a point at issues of environmental problems. For this study 11 questionnaires which were composed of large scale environmental problems(water and air pollution), and small scale environmental problems(food additives, GMO, endocrine disrupter) were performed with self-administered by university students(n=781) who made a application for liberal arts related to environmental subjects. According to the analysis the most student's consciousness of a point at issue of environmental problems(water pollution, air pollution, additives, GMO, endocrine disrupter), and practical attitudes(i.e., practical attendant at congregation and internet voting) were change statistically significant(p<0.01) after the education of a point at issue of environmental problems rather than before. Specially, the score for the item of the large scale problem of environmental issues(water pollution, air pollution) were decreased significantly(p<0.01), but the score for the small scale problems, such as food additives, GMO, endocrine disrupter were increased significantly(p<0.01) after the education of a point at issue of environmental problems(p<0.01). And among the students that participated, 97.7% responded that such a point at issues of environmental problem is needed at the university. With this educational improvements supports the states that the education of a point at issue of environmental problems were more essential, practical and needed to students at university rather than that of an existing instruction. Thus, further studies are required to develop the education of environmental issues at universities like STSE programme.

Reconfiguration Problems in VLSI and WSI Cellular Arrays (초대규모 집적 또는 웨이퍼 규모 집적을 이용한 셀룰러 병렬 처리기의 재구현)

  • 한재일
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.10
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    • pp.1553-1571
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    • 1993
  • A significant amount of research has focused on the development of highly parallel architectures to obtain far more computational power than conventional computer systems. These architectures usually comprise of a large number of processors communicating through an interconnection network. The VLSI (Very Large Scale Integration) and WSI (Wafer Scale Integration) cellular arrays form one important class of those parallel architectures, and consist of a large number of simple processing cells, all on a single chip or wafer, each interconnected only to its neighbors. This paper studies three fundamental issues in these arrays : fault-tolerant reconfiguration. functional reconfiguration, and their integration. The paper examines conventional techniques, and gives an in-depth discussion about fault-tolerant reconfiguration and functional reconfiguration, presenting testing control strategy, configuration control strategy, steps required f4r each reconfiguration, and other relevant topics. The issue of integrating fault tolerant reconfiguration and functional reconfiguration has been addressed only recently. To tackle that problem, the paper identifies the relation between fault tolerant reconfiguration and functional reconfiguration, and discusses appropriate testing and configuration control strategy for integrated reconfiguration on VLSI and WSI cellular arrays.

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Design Method for HTS Wire Length of the Small Scale Resistive Type Superconducting Fault Current Limiter Considering System Resistance (계통 저항을 고려한 소용량 저항형 한류기의 초전도 선재 소모 길이 산출 연구)

  • Lee, W.S.;Choi, S.J.;Jang, J.Y.;Hwang, Y.J.;Kang, J.S.;Yang, D.G.;Lee, H.G.;Ko, T.K.
    • Progress in Superconductivity and Cryogenics
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    • v.13 no.3
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    • pp.14-18
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    • 2011
  • Electrical system is changing to smart grid which includes the distributed generations with reusable energy sources in these days. The distributed generations are environmentally friendly and have no concern with depletion problem. But dispatching distributed generations can cause an increase of the fault current. Resistive type super conducting fault current limiter is one of the candidates of solution for the large fault problem in smart grid. In this paper, a design method for the wire length of fault current limiter and the result of short circuit test for small scale modules considering system resistance are introduced.

Protection of MPEG-2 Multicast Streaming in an IP Set-Top Box Environment

  • Hwang, Seong-Oun;Kim, Jeong-Hyon;Nam, Do-Won;Yoon, Ki-Song
    • ETRI Journal
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    • v.27 no.5
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    • pp.595-607
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    • 2005
  • The widespread use of the Internet has led to the problem of intellectual property and copyright infringement. Digital rights management (DRM) technologies have been developed to protect digital content items. Digital content can be classified into static content (for example, text or media files) and dynamic content (for example, VOD or multicast streams). This paper deals with the protection of a multicast stream on set-top boxes connected to an IP network. In this paper, we examine the following design and architectural issues to be considered when applying DRM functions to multicast streaming service environments: transparent streaming service and large-scale user environments. To address the transparency issue, we introduce a 'selective encryption scheme'. To address the second issue, a 'key packet insertion scheme' and 'hierarchical key management scheme' are introduced. Based on the above design and architecture, we developed a prototype of a multicasting DRM system. The analysis of our implementation shows that it supports transparent and scalable DRM multicasting service in a large-scale user environment.

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Enhancing the Narrow-down Approach to Large-scale Hierarchical Text Classification with Category Path Information

  • Oh, Heung-Seon;Jung, Yuchul
    • Journal of Information Science Theory and Practice
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    • v.5 no.3
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    • pp.31-47
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    • 2017
  • The narrow-down approach, separately composed of search and classification stages, is an effective way of dealing with large-scale hierarchical text classification. Recent approaches introduce methods of incorporating global, local, and path information extracted from web taxonomies in the classification stage. Meanwhile, in the case of utilizing path information, there have been few efforts to address existing limitations and develop more sophisticated methods. In this paper, we propose an expansion method to effectively exploit category path information based on the observation that the existing method is exposed to a term mismatch problem and low discrimination power due to insufficient path information. The key idea of our method is to utilize relevant information not presented on category paths by adding more useful words. We evaluate the effectiveness of our method on state-of-the art narrow-down methods and report the results with in-depth analysis.

GENERATION OF MAGNETIC FIELDS IN COSMOLOGICAL SHOCKS

  • MEDVEDEV MIKHAIL V.;SILVA LUIS O.;FIORE MASSIMILIANO;FONSECA RICARDO A.;MORI WARREN B.
    • Journal of The Korean Astronomical Society
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    • v.37 no.5
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    • pp.533-541
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    • 2004
  • The origin of magnetic fields in the universe remains an outstanding problem in cosmology. We propose that these fields are produced by shocks during the large-scale structure formation. We discuss the mechanism of the field generation via the counter-streaming (Weibel) instability. We also show that these Weibel-generated fields are long-lived and weakly coupled to dissipation. Subsequent field amplification by the intra-cluster turbulence may also take place, thus maintaining the magnetic energy density close to equipartition.

On Development of Lower Order Aggregated Model for the Linear Large-Scale Model

  • Yoo, Beyong-Woo
    • Korean Management Science Review
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    • v.15 no.2
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    • pp.125-142
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    • 1998
  • The aggregation on linear large-scale dynamic systems is examined in this paper and a "two-step" approach is proposed. In this procedure, the aggregated system consists of two subsystems. The first subsystem represents aggregation through the retainment of dominant eigenvalues of the original system, leading to a first approximation of the desired output of the original system. The purpose of augmenting it with a second subsystem is to provide an estimation of the error on the first approximation, thus permitting a second correction to the output approximation and resulting in an output approximation of greater accuracy. Optimization techniques are discussed for the determination of unknown parameters in the aggregated system. These techniques use minimization principles of certain suitable performance indices and are developed for both single input-single output and multiple input-multiple output system. Numerical examples illustrating these procedures are given and the results are compared with those obtained using existing methods. Finally, a pharmacokinetics problem is studied from the aggregation point of view.

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Autonomous Decentralized Container Terminal Operating System (자율 분산형 컨테이너 터미널 시스템)

  • 배민주;김환성
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2004.04a
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    • pp.393-397
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    • 2004
  • In these days, a scale of system is more and more complex and large. The centralized system has the operation management method to be limited in the large scale system. In this paper, we proposed ACOS(Autonomous decentralized Container terminal Operating System). It is applied to container terminal using by autonomous decentralized system which can solve the problem of the centralized operation system. Also, we can defined a function of the ACOS's sub-system and showed a flowchart on operation method for the ACOS.

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The Construction Methodology of a Rule-based Expert System using CART-based Decision Tree Method (CART 알고리즘 기반의 의사결정트리 기법을 이용한 규칙기반 전문가 시스템 구축 방법론)

  • Ko, Yun-Seok
    • The Journal of the Korea institute of electronic communication sciences
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    • v.6 no.6
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    • pp.849-854
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    • 2011
  • To minimize the spreading effect from the events of the system, a rule-based expert system is very effective. However, because the events of the large-scale system are diverse and the load condition is very variable, it is very difficult to construct the rule-based expert system. To solve this problem, this paper studies a methodology which constructs a rule-based expert system by applying a CART(Classification and Regression Trees) algorithm based decision tree determination method to event case examples.