• 제목/요약/키워드: network theory

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행위자-연결망 이론을 통해서 본 태백시 물 공급의 지리학 (Revealing Geography of Water in Taebaek City through Actor-Network Theory)

  • 김나형;김숙진
    • 대한지리학회지
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    • 제48권3호
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    • pp.366-386
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    • 2013
  • 본 연구는 2008년 동절기 가뭄으로 태백시가 단수 및 제한급수를 실시하게 된 과정을 행위자-연결망 이론을 적용하여 분석하였다. 행위자-연결망 이론은 다양한 환경생태문제에 있어 인간 행위자뿐만 아니라 비인간 행위자의 행위와 역할을 강조한다. 2008년 동절기 가뭄이 전국적으로 발생했으나 유독 태백시에서만 88일간 단수 및 제한급수를 실시하게 된 사실은 그 당시 태백시에 배태되어 있었던 인간, 비인간 행위자의 행위와 이들 간의 복잡한 관계, 연결망에 대한 종합적인 분석을 필요로 한다. 연구결과, 태백시청, 한국수자원공사 태백권관리단, 태백시민, 물공급 시설들, 광동댐, 노후한 상수도관, 지형, 토양, 산업 변화, 인구 등 다양한 인간, 비인간 행위자들이 다각적으로 작용하여 기존의 물공급망을 변화시킨 것을 알 수 있었다. 본 연구는 특정 로컬 스케일에서 가뭄재해와 관련된 복잡한 과정을 이해하는데 도움이 되며, 가뭄에 대한 적정한 대책을 강구하는데 도움이 될 것으로 보인다.

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NFT 아트의 미래와 전망 : 행위자네트워크 이론을 중심으로 (The Future and Prospects of NFT Art : On the basis of Actor-Network Theory)

  • 천미림;김홍규
    • 문화기술의 융합
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    • 제8권4호
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    • pp.397-405
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    • 2022
  • NFT 아트는 NFT 기술을 바탕으로 형성된 새로운 미술형태로써 기존 미술계와 미술시장에서 큰 관심을 끌고 있다. 따라서 NFT 아트가 새로운 미술의 영역으로 자리매김할 수 있는가에 대한 분석이 요구된다. 따라서 NFT 아트의 형성과 발전 과정을 과학기술학(Science and Technology Studies)의 행위자네트워크 이론(Actor-Network Theory)의 관점에서 분석하고 대표적인 사례로 NFT 아티스트 '비플(beeple)'의 사례를 조망한다. 또한 과학기술학 연구자인 그레이엄 하먼(Graham Harman)의 미학을 바탕으로 NFT 아트의 예술적 가치와 전통 미술 네트워크와의 관계를 논의한다. 특히 NFT 프로젝트 '크립토펑크(Crypto punks)'와 새로운 미술장르를 표방하는 '펑키즘(PUNKISM)' 사례를 통해 NFT 아트의 미래와 장르적 지속가능성을 분석한다. 행위자네트워크 이론으로 NFT 아트를 분석함으로써 기술적, 미적, 철학적 질문들을 가시화하고 새로운 미술장르로써의 긍정적인 전망을 제시하고자 한다.

Adaptive Clustering Algorithm for Recycling Cell Formation: An Application of the Modified Fuzzy ART Neural Network

  • Park, Ji-Hyung;Seo, Kwang-Kyu
    • 한국데이타베이스학회:학술대회논문집
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    • 한국데이타베이스학회 1999년도 춘계공동학술대회: 지식경영과 지식공학
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    • pp.253-260
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    • 1999
  • The recycling cell formation problem means that disposal products me classified into recycling part families using group technology in their end of life phase. Disposal products have the uncertainties of product status by usage influences during product use phase and recycling cells are formed design, process and usage attributes. In order to treat the uncertainties, fuzzy set theory and fuzzy logic-based neural network model are applied to recycling cell formation problem far disposal products. In this paper, a heuristic approach fuzzy ART neural network is suggested. The modified fuzzy ART neural network is shown that it has a great efficiency and give an extension for systematically generating alternative solutions in the recycling cell formation problem. We present the results of this approach applied to disposal refrigerators and the comparison of performances between other algorithms. This paper introduced a procedure which integrates economic and environmental factors into the disassembly of disposal products for recycling in recycling cells. A qualitative method of disassembly analysis is developed and its ai is to improve the efficiency of the disassembly and to generated an optimal disassembly which maximize profits and minimize environmental impact. Three criteria established to reduce the search space and facilitate recycling opportunities.

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다층 신경 망을 이용한 비중심F분포 확률계산 (Computation of Noncentral F Probabilities using multilayer neural network)

  • 구선희
    • 정보처리학회논문지B
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    • 제9B권3호
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    • pp.271-276
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    • 2002
  • ANOVA 검정에서 검정통계량은 단일 또는 이중 비중심F분포를 따르며 비중심F분포는 일반적인 선형 가설 검정에서 검정함수 계산에 적용되고 있다. 기존 비중심F분포의 함수 계산에 대한 연구로 여러 접근 방법이 제시되었지만, 하나의 정확한 함수값을 구하는데도 많은 시간이 소요되는 문제점이 발생되었다. 본 논문에서는 기존 함수 계산의 문제점을 해결하기 위하여 다층 퍼셉트론 네트워크로부터 역전파 학습 알고리즘을 적용하여 비중심F분포의 함수값을 구하는 방법을 제안하였다. 제안된 신경망에 의한 함수값과 기존 Patnaik이 제시한 분포식에 의한 함수값의 차이를 표와 그림을 통하여 비교하였으며, 정확성과 계산속도를 고려할 때 Patnaik의 함수식에 의한 방법보다 신경망을 이용한 방법이 효율적임을 알 수가 있다.

Adaptive Clustering Algorithm for Recycling Cell Formation An Application of the Modified Fuzzy ART Neural Network

  • Park, Ji-Hyung;Seo, Kwang-Kyu
    • 한국지능정보시스템학회:학술대회논문집
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    • 한국지능정보시스템학회 1999년도 춘계공동학술대회-지식경영과 지식공학
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    • pp.253-260
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    • 1999
  • The recycling cell formation problem means that disposal products are classified into recycling part families using group technology in their end of life phase. Disposal products have the uncertainties of product status by usage influences during product use phase and recycling cells are formed design, process and usage attributes. In order to treat the uncertainties, fuzzy set theory and fuzzy logic-based neural network model are applied to recycling cell formation problem for disposal products. In this paper, a heuristic approach for fuzzy ART neural network is suggested. The modified Fuzzy ART neural network is shown that it has a great efficiency and give an extension for systematically generating alternative solutions in the recycling cell formation problem. We present the results of this approach applied to disposal refrigerators and the comparison of performances between other algorithms. This paper introduced a procedure which integrates economic and environmental factors into the disassembly of disposal products for recycling in recycling cells. A qualitative method of disassembly analysis is developed and its aim is to improve the efficiency of the disassembly and to generated an optimal disassembly which maximize profits and minimize environmental impact. Three criteria established to reduce the search space and facilitate recycling opportunities.

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LTE-R의 도시철도 터널 환경 적용성 분석 (Analysis on Applicability of LTE-R in Urban Railway Tunnel Environment)

  • 곽우현;이광희;김용규;최준영
    • 전기학회논문지
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    • 제64권12호
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    • pp.1796-1803
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    • 2015
  • Unlike commercial LTE network, LTE-R railway network is arranged along a railroad track and the base stations of the network (RUs) are also installed on the waysides. For urban railway systems that are composed of underground tunnels, the leakage coaxial cables are widely used due to the radio propagation characteristics in tunnels. In theory, the tunnel sections are interpreted as the waveguide with blank spaces and for this reason, the tunnel sections are expected to be better than open ground sections in terms of the radio propagation characteristics. In this paper, we analyze the radio propagation characteristics based on this theory by replacing the leakage coaxial cables in the network with Yagi antennas. The test has been carried out in the 2.2km tunnel in the Daebul test track of KORAIL with 2.6GHz LTE-R Network. The LTE-R applicability in urban railways has been tested through the analysis on the radio propagation characteristics with the unmanned train operation system in Daebul tunnel.

A Flexible Network Access Scheme for M2M Communications in Heterogeneous Wireless Networks

  • Tian, Hui;Xie, Wei;Xu, Youyun;Xu, Kui;Han, Peng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권10호
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    • pp.3789-3809
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    • 2015
  • In this paper, we deal with the problem of M2M gateways' network selection for different types of M2M traffic in heterogeneous wireless networks. Based on the difference in traffic's quality of service (QoS) requirements, the M2M traffic produced by various applications is mainly classified as two categories: flexible traffic and rigid traffic. Then, game theory is adopted to solve the problem of network-channel selection with the coexistence of flexible and rigid traffic, named as flexible network access (FNA). We prove the formulated discrete game is a potential game. The existence and feasibility of the Nash equilibrium (NE) of the proposed game are also analyzed. Then, an iterative algorithm based on optimal reaction criterion and a distributed algorithm with limited feedback based on learning automata are presented to obtain the NE of the proposed game. In simulations, the proposed iterative algorithm can achieve a near optimal sum utility of whole network with low complexity compared to the exhaustive search. In addition, the simulation results show that our proposed algorithms outperform existing methods in terms of sum utility and load balance.

웨이블렛 신경망의 성장 알고리즘 (Growing Algorithm of Wavelet Neural Network)

  • 서재용;김성주;김성현;김용민;전홍태
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2001년도 춘계학술대회 학술발표 논문집
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    • pp.57-60
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    • 2001
  • In this paper, we propose growing algorithm of wavelet neural network. It is growing algorithm that adds hidden nodes using wavelet frame which approximately supports orthogonality in wavelet neural network based on wavelet theory. The result of this processing can be reduced global error and progresses performance efficiency of wavelet neural network. We apply the proposed algorithm to approximation problem and evaluate effectiveness of proposed algorithm.

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네트워크 외부성을 고려한 마케팅 채널 경쟁 분석 (Analysis of Marketing Channel Competition under Network Externality)

  • 조형래;이민호;임상규
    • 산업경영시스템학회지
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    • 제40권1호
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    • pp.105-113
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    • 2017
  • Network externality can be defined as the effect that one user of a good or service has on the value of that product to other people. When a network externality is present, the value of a product or service is dependent on the number of others using it. There exist asymmetries in network externalities between the online and traditional offline marketing channels. Technological capabilities such as interactivity and real-time communications enable the creation of virtual communities. These user communities generate significant direct as well as indirect network externalities by creating added value through user ratings, reviews and feedback, which contributes to eliminate consumers' concern for buying products without the experience of 'touch and feel'. The offline channel offers much less scope for such community building, and consequently, almost no possibility for the creation of network externality. In this study, we analyze the effect of network externality on the competition between online and conventional offline marketing channels using game theory. To do this, we first set up a two-period game model to represent the competition between online and offline marketing channels under network externalities. Numerical analysis of the Nash equilibrium solutions of the game showed that the pricing strategies of online and offline channels heavily depend not only on the strength of network externality but on the relative efficiency of online channel. When the relative efficiency of online channel is high, the online channel can greatly benefit by the network externality. On the other hand, if the relative efficiency of online channel is low, the online channel may not benefit at all by the network externality.

Robustness Evaluation of Tactical Network based on SNA

  • Park, Ji-Hye;Yoon, Soung-woong;Lee, Sang-Hoon
    • 한국컴퓨터정보학회논문지
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    • 제24권10호
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    • pp.205-213
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    • 2019
  • 네트워크 강건성은 네트워크의 가장 중요한 요구특성 중 하나이다. 전술 통신 네트워크에서 강건성은 공격 단계를 지속적으로 유지하는 핵심 기능이다. TICN이라고 하는 육군의 전술 통신 네트워크는 격자형과 트리형 네트워크 토폴로지가 혼합되어 있으며, 트리형 구조는 네트워크 강건성에서 다소 약하다. 따라서 본 논문에서는 그래프 이론을 적용하여 현재 전술 통신 네트워크의 취약점인 단절점과 브리지를 탐색하고 이 부분을 개선하기 위해 기존 네트워크에 링크를 추가하여 네트워크를 생성한다. 이후 SNA 기반 네트워크 강건성 평가를 위해 핵심 노드를 단절하여 각 네트워크의 지표 변화를 관찰한다. 실험 결과, 보완된 네트워크의 강건성이 기존 운용개념 하의 네트워크 구조보다 개선되었음을 보여준다.