• Title/Summary/Keyword: Exchange & Communication

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Continuous Control Message Exchange in Distributed Cognitive Radio Networks

  • Arega, Zerabruk G.;Kim, Bosung;Roh, Byeong-hee
    • Proceedings of the Korea Information Processing Society Conference
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    • 2014.04a
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    • pp.206-209
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    • 2014
  • Control message exchange is major job for cognitive radio to exist and use spectrum opportunistically. For this control message exchange they need a common control channel (CCC). Once this channel is affected by a primary user, communication stops until new CCC is setup. This takes substantial time and if they could not get free channel, this halt continues for long time. To prevent such cease of communication, we propose a combination of two networks, namely WLAN and UWB, to let the communication continue. In our proposed idea if the CCC of a certain CR in WLAN is affected, the CR changes its network from WLAN to UWB and keeps the communication because UWB cannot be affected by PU. In the proposed idea every cognitive radio has two transceivers; one for the overlay network (WLAN) and another UWB network. If a primary user is detected in the spectrum of a cognitive radio, it continues exchanging control messages under the UWB network and in parallel negotiates for a new CCC using the WLAN network. This idea solves the communication interruption until new CCC is setup.

Key Exchange Protocol based on Signcryption in SMART Highway (SMART Highway 환경에서의 사인크립션 기반 키 교환 프로토콜)

  • Kim, Su-Hyun;Lee, Im-Yeong
    • Journal of Korea Multimedia Society
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    • v.16 no.2
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    • pp.180-189
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    • 2013
  • The SMART Highway project combines road construction with advanced technology and vehicle telecommunications. Its expected outcome is a world-leading intelligent road that is green, fast, and comfortable. A vehicular ad-hoc network(VANET) is the core technology of the SMART Highway, whose transport operation is based on road vehicles. The VANET is a next-generation networking technology that enables wireless communication between vehicles or between vehicles and a road side unit(RSU). In the VANET system, a vehicle accident is likely to cause a serious disaster. Therefore, some information on safety is essential to serve as the key exchange protocol for communication between vehicles. However, the key exchange scheme of the general network proposed for a fast-moving communication environment is unsuitable for vehicles. In this paper, communication between multiple vehicles more efficient and secure key exchange at the vehicle certification by signcryption is proposed.

A Study on Characteristics of Library Space from the Perspective of Communication (커뮤니케이션학 관점에서 본 도서관 공간의 특성에 관한 연구)

  • Hwang, Mee-Young
    • Korean Institute of Interior Design Journal
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    • v.20 no.3
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    • pp.233-241
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    • 2011
  • Modern society is heading towards a knowledge & information based society where knowledge and information is valued, or a knowledge creation society where information is analyzed and processed to be used as knowledge. This means that not only individuals but also every organization is always surrounded by information and that we are witnessing a transition into a society where the value of knowledge and information is increasingly higher so sometimes we must actively explore and use the information across the whole social structure involved with politics, economy and culture. Recently, while the amount of information at public libraries at home and abroad has greatly increased in volume and the kinds have become diverse, efforts for digitalizing and integrating knowledge & information resources are being pursued aggressively. A new paradigm of facilities and space configuration for public libraries is required so that along with traditional library service there will exist integrated links and exchange of digital information resources and all users will be able to equally access that information. Therefore, assuming that human, information and space are important design factors as to space planning for public libraries, this study compared characteristics of the space structure and the form of exchange of knowledge & information through examples involved with public libraries having opened in the past three to four years from perspectives of space sociology and communication. This is a basic study to provide organized design guidelines about the form of exchange of creative knowledge & information from various perspectives in the knowledge & information age. Also this study is considered to have a significance in activating communication with users through exchange, creation and experience of knowledge & information, which is a social role that modern public libraries support.

Efficient All-to-All Personalized Communication Algorithms in Wormhole Networks (웜홀 방식 망에서의 효율적인 완전교환 통신 알고리즘)

  • Kim, Si-Gwan;Maeng, Seung-Ryoul;Cho, Jung-Wan
    • Journal of KIISE:Computer Systems and Theory
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    • v.27 no.5
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    • pp.464-474
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    • 2000
  • All-to-all personalized communication, or complete exchange, is at the heart of numerous applications, such as matrix transposition, fast Fourier Transform(FFT), and distributed table lookup.We present an efficient all-to-all personalized communication algorithm for a 2D torus inwormhole-routed networks. Our complete exchange algorithm adopts divide-and-conquer approach toreduce the number of start-up latency significantly, which is a good metric for network performancein wormhole networks. First, we divide the whole network into 2x2 basic cells, After speciallydesignated nodes called master nodes have collected messages to transmit to the rest of the basic cell,only master nodes perform complete exchange with reduced network size, N/2 x N/2. When finishedwith this complete exchange in master nodes, these nodes distribute messages to the rest of the masternode, which results in the desired complete exchange communication. After we present our algorithms,we analyze time complexities and compare our algorithms with several previous algorithms. And weshow that our algorithm is efficient by a factor of 2 in the required start-up time which means thatour algorithm is suitable for wormhole-routed networks.

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STUDY OF DETERMINISM OF DATA INTEGRITY DURING I/O DATA EXCHANGE BETWEEN TASKS AND DEVICE

  • Koo, Cheol-Hea;Park, Su-Hyun;Kang, Soo-Yeon;Yang, Koon-Ho;Choi, Sung-Bong
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.77-80
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    • 2007
  • In this paper, the method which can protect the situation of possible data corruption when collision has happened during I/O data exchange between device and tasks is presented. Also, an example diagram of mechanism according to this introduced method is shown and the effect and merits and demerits of the method is evaluated.

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Estimation of Hardware Sizing in Korean EMS System (한국형 EMS 하드웨어 Sizing 산정에 관한 연구)

  • Lee, Won-Sang;Lee, Hyo-Sang;Yi, Myoung-Hee;Kim, In-Hyun;Lee, Bong-Gil;Choi, Jin-Woo;Yeo, Hyun-Gu
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.412-413
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    • 2007
  • 정보시스템의 개발 및 유지보수에 대한 기준은 과기처 등에서 제정한 'S/W 개발비 산정기준'을 준용하고 있다. 그러나 본 기준이 Business Computing 환경을 기준으로 작성되었고, 전력계통 제어를 비롯한 각종 공정제어시스템 구축 환경에 부적합할 뿐 아니라 시스템의 뼈대(Frame)를 구성하는 H/W의 규모 산정이 누락되어 있는 상태이다. 전력거래소는 우리나라의 전력계통 환경에 적합한 한국형 에너지관리시스템(이하 K-EMS)의 국산화 개발을 각종 첨단 S/W의 탑재 기준에 따라 단계별(Baseline, Prototype, Fullscale)로 추진하면서, 각 단계에 가장 적합한 하드웨어의 용량 산정 기준을 선정하는 작업을 진행하고 있다. 이는 정보시스템 개발에서 자원의 낭비를 최소화하고 전체 개발비용을 절감 할 수 있다는 점에서 매우 중요하다. 본 연구에서는 K-EMS 시스템 국산화 개발을 위해 K-EMS가 수용할 각종 응용프로그램별 특성을 감안한 하드웨어의 적정 용량 산정 기준과 적용방안을 제시하고, CPU, Memory 등 세부 항목에 대한 고려항목을 언급함으로써 최적의 K-EMS 하드웨어 Sizing 산정방안을 소개하고자 한다.

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Implementation of fieldbus system for FMS (FMS를 위한 필드버스 시스템 구현)

  • 최형섭;장석호;남부희
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.399-402
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    • 1997
  • The fieldbus is one of the communication networks in control and automation systems and allows the exchange of information between sensors/actuators and controlling elements. By means of the fieldbus, the various field devices can exchange their information among the nodes in the system. In this paper, we implemented the protocol of profibus, a kind of fieldbus for communication in FMS plant model. We applied this fieldbus to the FMS plant model which consists of three stations and eight slave stations.

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Authenticated Key Exchange Protocol for the Secure and Efficient (안전하고 효율적으로 인증된 키 교환 프로토콜)

  • Park, Jong-Min;Park, Byung-Jun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.8
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    • pp.1843-1848
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    • 2010
  • The Key exchange protocols are very crucial tools to provide the secure communication in the broadband satellite access network. They should be required to satisfy various requirements such as security, Key confirmation, and Key freshness. In this paper, we propose Two authenticated key exchange protocols Two Pass EKE-E(Encrypted Key Exchange-Efficient) and Two Pass EKE-S(Encrypted Key Exchange-Secure) are introduced. A basic idea of the protocols is that a password can be represented by modular addition N, and the number of possible modular addition N representing the password is $2^N$ The Two Pass EKE-E is secure against the attacks including main-in-the-middle attack and off-line dictionary attack, and the performance is excellent so as beyond to comparison with other authenticated key exchange protocols. The Two Pass EKE-S is a slight modification of the Two Pass EKE-E. The Two Pass EKE-S provides computational in feasibility for learning the password without having performed off line dictionary attack while preserving the performance of the Two Pass EKE-E.

IEC 61970 CIM based Study on the application of model for Wide Area Monitoring And Control System (IEC 61970 CIM을 기반으로 한 Wide Area Monitoring And Control system 모델 적용 연구)

  • Cho, Jun-Hee;Oh, Young-Suk;Choi, Mi-Hwa;Shin, Seung-Hee;Kim, Ji-Young
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.178-179
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    • 2011
  • The exchange of information with legacy systems is a main issue in the era of SMARTGRID. Because WAMAC(Wide Area Monitoring and Control) system has monitoring function, as well as control function, it is very necessary for WAMAC to exchange data and information with SCADA(Supervisory Control and Data Acquisition) / EMS(Energy Management System). IEC 61970 CIM(Common Information Model) is an abstract model that represents all the major objects in an electric utility enterprise typically involved in utility operations. In this paper, a proposal that adopting CIM to WAMAC model be submitted so that the integration of various legacy system and application for itself be able to be flexible.

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Hypermedia Models for CALS Environment (CALS환경에서의 하이퍼미디어 모델 적용에 관한 연구)

  • 임만택
    • The Journal of Society for e-Business Studies
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    • v.1 no.1
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    • pp.159-171
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    • 1996
  • Nowadays, multimedia and Hypermedia become hot topics in information industry. Due to high capacity of media storage and fast communication network, it is possible to exchange text data as well as image, moving picture and voice. Especially to apply hypermedia under CALS standard environment, the relation between international standard and CALS standard needs to be considered. This study introduces conceptual background and processing model of HyTime (Hypermedia Time-based Structuring Language) which is a specification of hypermedia exchange, Hyper ODA (Hyper Open Document Architecture) which is a major multimedia communication basis, MMCF (Multimedia Communication Forum), AHM(Amsterdam Hypermedia Model), and DSRM(DAVIC System Reference Model) reference model which helps determination of hypermedia communication specification Although they are international standard, provisional standard or non-standard, it discusses the Possibility of adopting them as CALS standard. Hence, this paper chooses the best recommend for CALS among these models.

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