• Title/Summary/Keyword: 광 무선통신

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Development of Metadata based Information Exchange Technique among Electric Power Monitoring and Management Systems (메타데이터 기반 전력설비 감시 및 제어 시스템 간의 정보 교환 기법에 관한 연구)

  • Hong, Chang-Ho;Park, Chan-Eom;Lee, Seung-Chul;Moon, Un-Chul
    • Proceedings of the KIEE Conference
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    • 2005.11b
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    • pp.331-333
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    • 2005
  • 최근 전력시스템이 점차 복잡해지고 대규모화 되어감에 따라 신뢰도 높은 운영이 어려워지고 그에 따라 세계 여러 나라에서 광역정전이 비교적 자주 발생되고 있다. 전력시스템의 보다 신뢰도 높은 운용을 위하여는 궁극적으로 발전, 송전, 변전 및 배전에 이르는 전 과정에 걸쳐 수평적 및 계층적으로 구성되어 있는 각 설비들의 감시 및 운용시스템들 간에 자율적이고 신속한 정보 교환이 가능하여야 한다. 주로 단순한 시퀀스 제어를 위하여 운용 시스템들 간의 통신수단으로 사용되던 기존의 시리얼 통신 기술은 TCP/IP를 지원하는 광통신 및 무선 네트워크 시스템으로 대치되어 왔고 이를 바탕으로 보다 효과적인 전력설비 및 시스템의 감시 및 제어가 가능하게 되었다. 본 논문에서는 SOAP[1] 및 UDDI[2]기술을 바탕으로 하는 표준화된 웹 서비스를 이용하여 전력실비간 정보전달 기법을 소개함으로써 전력시스템의 유비쿼터스 화를 촉진하여 언제, 어디서, 어떤 설비들 간에서도 전력운용정보를 자율적으로 교환하는 것을 가능케 하기 위한 기반기술에 대하여 논의하고자 한다. 네트워크망과XML을 이용한 메타데이터를 바탕으로 전력설비 감시 및 운용 시스템들간의 통신 시스템을 구축하기 위한 확장성과 사용자 편리성을 증대시킨 정보교환 기법에 대하여도 논의하고자 한다.

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A Study on The Mutually Authentication Mechanism for The Safe Electronic Signature (안전한 전자서명을 위한 상호인증 메커니즘에 관한 연구)

  • Choi, Sang-Wook;Chae, Cheol-Joo;Lee, Jae-Kwang
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.10a
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    • pp.772-775
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    • 2008
  • As the wireless communication technology developed, the Electric Commerce using a mobile was activated. WPKI was developed in order to guarantee the stability of the Electric Commerce but it is difficult to be ensured for the safe PKI service which is the same at the wire communication in the technical because of restriction of the mobile terminal. In this paper, we propose the authentication system for the electronic financial service which is safe and is effective in consideration of the restrictive characteristic of the mobile terminal. Moreover, the encryption algorithm for the safe electronic signature is proposed. In WPKI, this makes the cross certification of each certificate authority possible. Moreover, a stability was enhanced through the signature authentication using KCDSA and SEED algorithm.

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Experimental Analyses and Millimeter Wave Signal Generation Using Sideband Injection Locking Method (측파대 광 주입 락킹 기법을 이용한 밀리미터파 신호생성 및 실험적 분석)

  • Kim, Jung-Tae
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.12
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    • pp.2769-2774
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    • 2010
  • In this paper, we have proposed sideband injection locking method, heterodyne technique, to generate millimeter-wave signal. Microwave signals in cellular broadband mobile communication networks and distributed networks can favorably be generated and distributed by optical techniques. In principle, these techniques have already been investigated for optical control of phase-array antennas, characterization of photo-detector and phase locking of millimeter-wave oscillators and now being applied to wireless communications. The generation and transmission of millimeter-wave radio signals by optical means is of interest for future pico-cell broadband mobile communication system, especially for systems operating at frequencies of tens of GHz applicable to LMDS. We experimented and analysed the generation of millimeter wave signal.

Self-powered wireless bus information and disaster information system based on Internet of Things (IoT) (사물인터넷 기반의 자가 전력을 이용한 무선 버스 정보 및 재난 정보 시스템)

  • Kim, Tae-Kook
    • Journal of Internet of Things and Convergence
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    • v.8 no.1
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    • pp.17-22
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    • 2022
  • This paper is a study on the self-powered wireless bus information and disaster information system based on Internet of Things (IoT). The existing bus information system supplies power and communication by cable, which causes a problem of increased installation cost and limited installation site due to cable burial. To solve this problem, a self-powered wireless bus information and disaster information system was proposed. The proposed system provides bus arrival information. Furthermore, in the event of a disaster such as a natural disaster, it can also reduce confusion and damage by notifying the disaster information through the system's speaker. In this study, a self-powered system using a solar module was proposed. As data are transmitted and received through wireless WiFi or LTE, the installation cost can be reduced and the problem of installation location restrictions can be solved.

A Study on The Rotation Invariant Fingerprint Identification Using a Circular Harmonic Filter (순환 고조파 필터를 이용한 회전불변 지문 인식에 관한 연구)

  • 신강호;채호병;정연만
    • Journal of the Korea Society of Computer and Information
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    • v.8 no.3
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    • pp.94-99
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    • 2003
  • In this paper, a rotation invariant fingerprint identification system is implemented using the circular harmonic filter and phase only correlator. We extracted the phase component from input fingerprint image and correlate it with the circular harmonic filter of the reference fingerprint image by POC. The input image is obtained using a prism operating in the internal full reflection mode. Then the input image is transformed to two dimensional Fourier spectrum in optical way and the phase component is extracted using a digital system from the spectrum. Because composed of the optical system and digital algorithm, the proposed system has the advantages of the two technologies such as realtime parallel processing property of the optics and the flexibility of the digital system.

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A Study on Realization and Receiving Characteristic Analysis of Visible Light Wireless Communication System for Power Line Communications Using ATmega16 Microcontroller (ATmega16 마이크로컨트롤러를 이용한 전력선통신용 가시광 무선통신 시스템 구현 및 수신 특성 분석)

  • Yun, Ji-Hun;Hong, Geun-Bin;Kim, Yong-Kab
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.11
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    • pp.2043-2047
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    • 2010
  • This study is to solve problems of depletion of RF bandwidth frequency, confusion possibility, security that current wireless communications system have and is to confirm possibility of applying next generation network. To solve problems of current wireless communications system, visible light communications system for power line communications using ATmega16 Microcontroller is was realized and receiver property was analyzed. PLC exclusive chip APLC-485MA, Microcontroller ATmega16, 5pi bulb type LED and high flux LED, visible light receiving sensor LLS08-A1 were used for transmitter and receiver. Performance was analyzed by designed program and an oscilloscope. It was showed average 20% improved receiver rate rather than bulb type LED in the case of high flux LED through voltage change rate on communication distance and LED type of distance between 10 to 50 cm. The blue LED showed the best performance among measured LED types with above 10% of voltage decreasing rate. But As it gradually becomes more distant, the precise date was difficult to obtain due to weak light. To overcome these sort of problems, specific values such as changing conditions and efficiency value relevant to light emitting parts and visible light receiving sensor should be calculated and continuous study and improvements should also be accomplished for the better communications condition.

Implementation of Secure I-Mail System based on lava (타원곡선 알고리즘을 이용한 안전한 자바 메일 시스템의 설계 및 구현)

  • 이원구;조한진;이재광
    • Proceedings of the Korean Information Science Society Conference
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    • 2001.10a
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    • pp.700-702
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    • 2001
  • As computers and networks become popular, distributing information on the Interment is common in our daily life. Also, the explosion of the Internet, of wireless digital communication and data exchange on Internet has rapidly changed the way we connect with other people. But secure mall is gamins popularity abroad and domestically because of their nature of prodding security. That is. it has been used a variety of fields such as general mail and e-mail for advertisement But, As the data transmitted on network can be easily opened or forged with simple operations. Most of existing e-mall system don't have any security on the transmitted information. Thus, security mail system need to provide security including message encryption, content integrity, message origin authentication, and non-repudiation. In this paper, we design implement secure mall system with non-repudiation service and encryption capability to provide services for certification of delivery and certification of content as well as the basic security services.

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Wireless Bridge Health Monitoring System for Long-term Measurement of Small-sized Bridges (중소교량의 지리적 특성을 고려한 무선 전력 및 통신 기술 기반 교량 장기 계측시스템 구축 방안 연구)

  • Tae-Ho Kwon;Kyu-San Jung;Ki-Tae Park;Byeong-Cheol Kim;Jae-Hwan Kim
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.27 no.4
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    • pp.86-93
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    • 2023
  • A bridge health monitoring technology is under development for the safety management of aged bridges. The bridge health monitoring technology has been developed mainly for single bridge management at a large scale, so it uses wire-based systems for power supply and data transfer. However, the wire-based systems need to be improved for the sporadically distributed small-sized bridges on local roads. This study proposed a wireless structural health monitoring system for small-sized bridges. The proposed monitoring system overcomes the limitations of wired systems by providing wireless power through solar power and utilizing LTE technology to transmit measurement data. In addition, a remote control system and power management plan were proposed to ensure the stability of the bridge measurement system. The proposed measurement system was installed on 32 bridges on fields and verified the operability by collecting 80.6% of measurement data for one year. The proposed system can support the health monitoring of aged bridges on local roads.

Cluster Based Routing Protocol Using Fixed Cell in Mobile Ad hoc Networks (MANET) (Mobile Ad Hoc Networks(MANET)에서의 고정셀을 이용한 Cluster Based Routing Protocol)

  • 정종광;김재훈
    • Proceedings of the Korean Information Science Society Conference
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    • 2002.04a
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    • pp.583-585
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    • 2002
  • Mobile Ad Hoc Network에서는 무선으로 연결된 호스트들이 쉽게 이동할 수 있으며 미리 설치된 유선망을 이용하는 셀롤러망과 달리 이동 호스트 사이의 통신만으로 이루어진 망이다. Mobile Ad Hoc Network에서는 각각의 노드들의 이동성이 높기 때문에 이 각각의 노드들의 라우팅 경로를 결정하는 것이 중요하다. 이에 따라 Mobile Ad Hoc Network를 위한 많은 라우팅 프로토콜이 제안되었다. 본 논문에서는 기존에 제안된 Cluster Based Routing Protocol(CBRP)극 변형하여 마치 셀롤러망에서의 셀과 같이 고정된 위치를 하나의 셀로 정의하고 그 하나의 셀이 클러스터를 형성하여 라우팅 오버 헤드를 줄일 수 있는 기법을 제안한다.

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Zigbee Based Wireless Respiration Monitor System (지그비 통신 기반의 근거리 무선 호흡모니터 시스템)

  • Lee, In-Kwang;Kim, Seong-Sik;Jang, Jong-Chan;Kim, Koon-Jin;Kim, Kyung-Ah;Lee, Tae-Soo;Cha, Eun-Jong
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.1
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    • pp.142-147
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    • 2008
  • Abdominal circumference changes due to breathing by the respiratory muscle activity such as diaphragm, which would partially represent the lung volume variation. The present study introduced conductive rubber molded in a cord shape incorporated with a patient's pants. The conductive rubber cord operated as a displacement transducer to measure the lung or abdominal volume changes. Signal extraction circuitry was developed to obtain the volume and its derivative(or the flow) signals followed by wireless transmission based on the Zigbee communication protocol in a size of $65mm{\times}105mm$ easily put in pocket. Breathing frequency was accurately evaluated and breath pattern analysis seemed feasible, since respiratory behaviours such as maximal inspiration and cough were well identified. Remote wireless receiver module also enabled to monitor both volume and flow signals during resting breathing on a PC terminal.