• Title/Summary/Keyword: Multi-networking

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Multi-Channel Multi-Interface Active RFID Reader and Protocol (다중 채널 다중 인터페이스 능동형 RFID 리더 및 프로토콜)

  • Park, Hyun-Sung;Kim, Dong-Hyun;Chung, Sang-Hwa;Baek, Yun-Ju;Kim, Jong-Doek
    • Journal of KIISE:Information Networking
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    • v.36 no.2
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    • pp.118-129
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    • 2009
  • The ISO 18000-7 Active RFID standard, a single channel system operating in the 433Mhz, faces technical difficulties in supporting some recently introduced application demands because of its low transmission rates and radio interference between readers. We propose a new multi-channel active RFID system operating in the 2.4Ghz. The special feature of the proposed system is that a reader makes use of multiple interfaces to improve its performance like a multi-core processor. However if only a small part of interfaces are actually used, the performance improvement would not meet the expectation. To overcome this problem, a new multi-channel multi-interface active RFID protocol, which balances communication loads among all available interfaces, is necessary. 3 protocols, named as "Aggregated", "LP-Combined", "AP-Balanced", are proposed. Through simulation, we compare them for various conditions by changing number of tags, number of interfaces, tag data size. AP-Balanced shows the best performance and its performance increases almost linearly as the number of interface increases, which meets our expectation.

A Control Channel Access Scheme for Clustered Multi-interface Multi-hop Cognitive Radio Networks (클러스터 형태의 다중 인터페이스 다중 홉 인지 라디오 네트워크를 위한 제어 채널 접근 기법)

  • Lee, Ji-Wun;Jeon, Wha-Sook;Jeong, Dong-Geun
    • Journal of KIISE:Information Networking
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    • v.37 no.4
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    • pp.301-306
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    • 2010
  • We propose the control channel access scheme for multi-interface multi-hop cognitive radio (CR) environment having a cluster structure. Due to the difficulty of obtaining common channels across the entire CR network, most multi-interface multi-hop CR networks put the control channel outside the CR bandwidth and dedicate one network interface to it in order to exchange the control information such as the activation of licensed users. However, this will be the waste of the network interface. Our focus is how to alternate between the control and the data channel without multichannel hidden node problem under the cluster structure where CR nodes connect with neighbors through multiple data channels. By using simulation, we evaluate the performance of the proposed scheme. The results show that the proposed scheme achieves higher network throughput than the dedicated scheme where one network interface card should dedicate to the control channel and cannot be used for data transmission.

Design of QoS Supporting Mechanism using Openflow Protocol in Wireless Mesh Network Environments (무선 매시 네트워크 환경에서 오픈플로우 프로토콜을 이용한 QoS 지원 기법 설계)

  • Kang, Yong-Hyeog;Kim, Moon Jeong;Kim, Su-Sun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.9
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    • pp.34-41
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    • 2017
  • Wireless mesh networks contain multi-hop routing protocols between wireless nodes and are connected to the Internet through a gateway. These networks perform a role as a backbone and are scalable for main applications. We propose the design of QoS supporting mechanisms for wireless mesh networks using software defined networking. Our proposed scheme is cost-effective and features adaptive QoS mechanisms for wireless router's resource constraints. The QoS mechanisms use software defined networking technology with Openflow protocol based on diffserv and intserv models with MPLS mechanism and RSVP respectively. A performance evaluation model is suggested to verify the validity of the proposed scheme using several QoSmetrics of the wireless mesh networks.

The Relation between Social Networking Sites and Depression by Gender: Mediating effects of Collective Identity, Perceived Social Support, and Negative Comparison (성별에 따른 SNS사용유형이 우울감에 미치는 영향연구: 집단소속감, 지각된 사회지지, 부정적 사회비교의 매개효과)

  • Lee, Seunguk;Choi, Younyoung;Lee, Hyunwoo
    • Journal of the Korea Convergence Society
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    • v.10 no.8
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    • pp.205-215
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    • 2019
  • The purpose of this study aimed to investigate the gender differences in the mediating effects of perceived social support and negative comparison in the relation between social networking sites and depression. For this analysis, 483 samples were collected and conducted by multi-group structural equation model. The findings of this study were as follows: (1) Collective identity was observed both in Facebook and in Internet Cafe activities. (2) Collective identity was positively related to perceived social support, but perceived social support was negatively related to depression. Also, negative comparison was positively related to depression. (3) In terms of gender differences, the Facebook activities were negatively related to depression for male while the internet cafe activities were positively related to depression for female. Lastly, (4) The collective identity was positively related to negative comparison for female.

The Effects of Sports Star Influencer Advertising Value and Consumer Team Identification on Brand Equity (스포츠 스타 인플루언서 광고가치와 소비자 팀동일시가 브랜드자산에 미치는 영향)

  • Lee, Jin Kyun;Um, Namhyun
    • The Journal of the Korea Contents Association
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    • v.21 no.6
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    • pp.180-196
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    • 2021
  • The goal of this research is to examine the effects of sports star influencer advertising value on brand equity in social networking sites. In particular, this study identifies the moderating role of consumer team identification. A total of 350 university students participated via online survey. To test proposed hypotheses, confirmatory factor analysis, structural equation modeling, and multi-group analysis were employed. It was found that informativeness, entertainment, and credibility showed significant positive effects on brand equity. Also, significant moderation effects of team identification were found in that consumers with high team identification compared to those with low team identification perceived higher value of entertainment. On the other hand, consumers with low team identification perceived more irritation than those with high team identification. This study contributes to the understanding of sports star influencer advertising in social networking sites. Theoretical and practical implications as well as suggestions for future research in this area are provided.

Survey on Disrupt-/Delay-Tolerant Networking in Vehicular Networks (차량네트워크에서 지연감내형 네트워킹 연구동향)

  • Jung, H.Y.;Jeong, J.H.;Choo, C.C.;Hong, Y.G.
    • Electronics and Telecommunications Trends
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    • v.32 no.4
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    • pp.67-77
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    • 2017
  • 최근 이슈가 되고 있는 자율주행차(Autonomous vehicle 또는 Self-driving car)를 실현하기 위해서는, 다양한 환경에서도 차량에 대한 끊김 없는 연결을 제공하는 커넥티드카(Connected car) 기술이 필수적이다. 현재 커넥티드카를 구현하기 위한 차량 네트워크(Vehicular network) 기술은 교통시스템 인프라 기반의 단일홉(Single-hop) 무선통신 기술이 주를 이루고 있다. 이러한 단일홉 통신은 커버리지가 교통시스템 인프라가 구축된 지역으로 제한된다. 따라서 차량 네트워크가 현재보다 더욱 넓은 지역을 커버하기 위해서는 차량 자체가 이동형 라우터 역할을 수행하여 차량 간의 전달을 통해 정보를 원거리로 전달할 수 있는 다중홉(Multi-hop) 통신 도입이 필요하다. 다중홉 차량 네트워크는 차량의 높은 동적 특성으로 인해 다수의 도전적인 기술적 이슈들을 가진다. 본고에서는 이러한 기술 이슈 중 차량 네트워크의 높은 이동성으로 발생할 수 있는 종단 노드 간 비연결성을 해결할 수 있는 기술인 지연감내형 차량 네트워킹(Delay-tolerant vehicular networking) 기술에 대한 주요 연구 동향을 살펴보고자 한다. 이를 위해 먼저 지연감내형 차량 네트워킹의 기술적 배경 및 주요 관련 기술들을 분석하고 이를 기반으로 향후 연구개발이 필요한 기술 이슈들을 정리한다.

New Strategy of Forest Tree Breeding for Society, Forest Science, and Forestry in Korea

  • Choi, Yong-Eui;Kim, Chul-Woo;Yi, Jae-Seon
    • Journal of Forest and Environmental Science
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    • v.24 no.1
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    • pp.15-25
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    • 2008
  • Social and scientific changes, i.e., global warming, desertification, pollution, biodiversity, bioenergy, plant variety protection, biotechnology, timber demand, reforestation in North Korea, and etc., were reviewed for new strategy of forest tree breeding in Korea. Diversified breeding goals, globalization of breeding target species, multidisciplinary research approaches, manpower networking, establishment of new administrative and research units in KFS and KFRI were proposed. Principles suggested for new tree breeding strategy are: 1) multi-disciplinary approach in settlement of objectives, breeding methods, and etc., 2) expansion of target trees including foreign species, 3) fulfillment of both domestic and international demands for forest tree breeding, 4) establishment of breeding program well-grounded on genetic resources conservation, 5) acknowledgement of breeding products (i.e., variety, technique, gene, and etc.) as goods, and 6) provision of more research opportunities for young scientists. Lastly, ongoing tree breeding project in Indonesia and NTFP R&D Center at the College of Forest and Environmental Sciences, Kangwon National University were introduced as examples of desirable breeding projects based on target species diversification, multidisciplinary approach, and manpower networking.

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Network Coding Performance Analysis with Multicast Topology (Multicast Topology에서의 네트워크 코딩 성능 분석)

  • Lee, Mi-Sung;Balakannan, S.P.;Lee, Moon-Ho
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.11
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    • pp.30-35
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    • 2010
  • Network coding is a new research area that may have interesting applications in practical networking systems. With network coding, intermediate nodes may send out packets that are linear combinations of previously received information. The exploration of numerical, theoretical and operational networking issues from new perspectives that consider coding at network nodes. We have presented a network coding approach which asymptotically achieves optimal capacity in multi-source multicast networks. Our analysis uses connections that we make between network coding. In this paper we analysed with and without network coding performance. Also we discussed the simulation results on network coding with linear optimization problem and it shows how network coding can be used.

Performance Modeling of STTC-based Dual Virtual Cell System under the Overlay Convergent Networks of Cognitive Networking (중첩 융합 네트워크 환경을 고려한 STTC기반 이중 셀 시스템 분석 모델)

  • Choi, YuMi;Kim, Jeong-Ho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.49 no.12
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    • pp.20-26
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    • 2012
  • The newly introduced model of a STTC-based Distributed Wireless Communication System (DWCS) can provide the capability of joint control of the signals at multiple cells. This paper has considered the virtual cell systems: the Dual Virtual Cell (DVC), and also proposes DVC employment strategy based on DWCS network. The considered system constructs DVC by using antenna selection method. Also, for multi-user high-rate data transmission, the proposed system introduces multiple antenna technology to get a spatial and temporal diversity gain and exploits space-time trellis codes known as STTC to increase a spectral efficiency.

무선 홈 네트워킹 기술 표준화 동향 및 발전 전망

  • 전호인
    • Information and Communications Magazine
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    • v.21 no.3
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    • pp.13-40
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    • 2004
  • 홈 네트워킹은 다양한 유ㆍ무선 네트워킹 기술을 적용하여 개개인의 생활을 더 윤택하게 해 주는 서비스를 제공하고 이를 통해 커다란 시장을 형성할 수 있는 미래의 신 성장 동력 산업이다. 이를 위해 PLC, IEEE 1394, HomePNA와 같은 유선 홈 네트워킹 기술은 물론 WLAN, WPAN, UWB 등과 같은 무선 네트워킹 기술이 여러 가지의 응용 분야를 무기로 자신의 영역을 차지하려 하고 있다. 따라서 댁내의 기기는 이와 같은 네트워킹 기술을 지원하도록 설계되어야 하지만, 그 위에 UPnP나 HAVi, Jini, HNCP 등과 같은 미들웨어가 탑재되어야 상호 호환성이 지원된다. 그리고 하나의 표준화된 H/W나 S/W 플랫폼 위에 혼 게이트웨이가 동작하면 집 외부에서 원격으로 새로운 서비스를 지원할 수 있게 되며 응용 분야가 다양하게 확장될 수 있다. 그 위에 유비퀴터스 네트워킹 개념을 도입하여 홈 네트워크가 필요로 하는 서비스를 지원함으로써 커다란 시장을 이끌어 갈 수 있게 된다. 본 논문에서는 홈 네트워킹 기술의 표준화 현황에 대해 정리하고, 차세대 성장 동력으로서의 홈 네트워킹을 위해 반드시 적용해야 할 유비퀴터스 네트워킹 개념과 이로부터 효과를 얻기 위해 집안에 홈 네트워크를 어떻게 수용하게 할 것인지에 대해 논하였다. 끝으로 유비퀴터스 네트리킹을 통한 막대한 시장을 먼저 확보하기 위한 무선 홈 네트워킹 기술의 아키텍처를 정하면서 이를 구현하기 위해 먼저 수행해야 할 Mesh Networking 기술 및 Multi-Hop 네트워킹 기술과 같은 연구분야에 대해 논하였다.(중략)