• 제목/요약/키워드: Communication system

검색결과 24,192건 처리시간 0.045초

A Study on Mobile Communication system using Stillness Image

  • Lee, Jung-Ho;Han, Dae-Mun;Kim, Yeong-Real
    • 한국산업정보학회:학술대회논문집
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    • 한국산업정보학회 2007년도 춘계학술대회
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    • pp.35-39
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    • 2007
  • We applied digital image processing about BitMap file structure in this research and studied about digital communication system. digital record saving devices can express 'High' and 'Low' as all data. Only, digital technique that two expression methods is used into several expenditures. People and communication that are far away by development of digital technology, became smooth. We wished to make communication system taking advantage of digi-tech. This system was made for communication with disabled and normal person specially. To communication method that we are studied such BitMap file handling image communication system. The goal of this contribution is to present the overview of basic algorithms for image processing using BitMap.

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Performance Analysis of Hybrid SIMO-RF/FSO Communication System with Fixed Gain AF Relay

  • Shi, Wenxiao;Kang, Kai;Wang, Zhuo;Liu, Wei
    • Current Optics and Photonics
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    • 제3권5호
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    • pp.365-373
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    • 2019
  • This paper investigates the performance of a hybrid single input multiple output radio frequency/free-space optics (SIMO-RF/FSO) communication system. Each SIMO-RF link is modeled as an independent and identically distributed (i.i.d.) Rayleigh distribution, while the FSO link follows a generalized $M{\acute{a}}laga$ (M) distribution. Considering the fixed gain amplify-and-forward (AF) relay and misalignment errors, novel expressions for the outage probability (OP), average bit error rate (ABER) and average capacity are derived. Numerical results show that atmospheric turbulence and misalignment errors can seriously impair the system performance, and the hybrid RF/FSO communication system using SIMO-RF links can greatly improve system performance. We also analyze system performance under different types of modulation schemes. Numerical results are verified by Monte Carlo simulations.

Mastey-Slave 개념을 이용한 PLC용 다대다 통신 모듈 개발 (A multiple PLC wireless communication module using master-slave control concept)

  • 박종석;현웅근;김이곤
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.48-48
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    • 2000
  • We developed a wireless communication system for multiple instrumentation system. The developed system has a function of remote instrumentation and PLC(Programmable Logic Controller) control. The system consists of CC(Control and Communication) protocol, wireless media access and physical media system. For multiple wireless communication, we propose a hub polling protocol based on master-slave control concept. To show the validity of the developed system, several experiments are illustrated.

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DNP3.0 프로토콜을 이용한 배전계통 멀티 에이전트 보호시스템의 통신 모듈 개발에 관한 연구 (A Study on the Development of an Agent Communication Module for a Multi-Agent Based Power Distribution Network Protection System Using DNP 3.0 Protocols)

  • 최면송;이한웅;민병운;정광호;이승재;현승호
    • 대한전기학회논문지:전력기술부문A
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    • 제52권9호
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    • pp.506-512
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    • 2003
  • In this paper, a communication module between Relay agents in a multi-agent system based power distribution network protection system is realized using DNP3.0(Distributed Network Protocol), which is the standard communication protocol of distribution automation system in KEPCO. The key words for agent communication in the multi-agent based protection system are defined and represented by use of DNP application function code. The communication module developed based on the proposed communication scheme is tested by use of the Communication Test Harness, a test tool for DNP protocol, then used to the multi-agent system based power distribution net work protection system.

선박 주기관 원격제어시스템을 위한 통신방식에 관한 연구 (A Study on the Communication Method for a Ship Main Engine Remote Control System)

  • 류길수
    • Journal of Advanced Marine Engineering and Technology
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    • 제22권6호
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    • pp.894-900
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    • 1998
  • In this paper, a communication method is proposed for the development of a main engine remote control system. The main engine control system compriese three subsystems such as RCS (Remote Control System) BCS (Bridge Control System) and SS (Safety System), Thus it is required to exchange data each other among these subsystems. The communication method has simplified hardware through the minimization of communication components where the interrupt method are employed for receiving and the polling method for transmitting. We discuss a methodology of using a ring buffer for data storage physically which has two buffers virtually for the effective use of memory. This communication method presents a good performance in the system which has rather small numbers of communication data.

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이동통신망 관리용 운용시스템 설계에 관한 연구 (A Study on the design of operations system for managing the mobile communication network)

  • 하기종
    • 한국시뮬레이션학회논문지
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    • 제6권2호
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    • pp.71-79
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    • 1997
  • In this paper, operations system was designed for the centralization of data processing of various state information from the facilities of mobile communication network. And the system performance experimental system module was measured and analyzed from the designed experimental system module. The configuration of system design was presented with the centralized type to monite and control the facilities of mobile communication network in the central office. The communication process design of the internal system was implemented with the resource of message queue having a excellent transmission ability for processing of a great quantity of information in the inter-process communication among communication resources of UNIX system. The process with a server function from the internal communication processes was constructed with a single server or a double server according to the quantity of operations and implemented with the policy of the presented server. And then, we have measured performance elements in accordance with the change of input parameters from the designed experimental module : response time, waiting time, buffer length, the maximum quantity existing in message queue. And from these results, we have compared and analyzed the system state each server algorithm according to performance variations.

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자동차 네트워크 시스템을 위한 FlexRay 드라이버 개발 (The Development of FlexRay Driver for Vehicle Network System)

  • 구용제;김종철;신충엽;박상종
    • 제어로봇시스템학회논문지
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    • 제16권6호
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    • pp.546-552
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    • 2010
  • As the demands for the safety and convenience applications of the vehicles increase, the data load for the In-vehicle Network has increased significantly. As a result, a deterministic and fault-tolerant communication system is required to implement the safety critical applications such as X-by-wire systems. FlexRay communication system is a new standard of network communication system which provides the high speed serial communication, time triggered bus and fault tolerant communication between electronic devices. In addition to time-triggered communication, as providing of the event-triggered communication such as CAN, FlexRay protocol is able to manage the restricted communication resource more effectively. This paper presents the development of FlexRay driver which will be applied to the future ECU's communication system. To develop the FlexRay driver, the FlexRay requirement specification and FlexRay specification is analyzed. The developed FlexRay driver is implemented by using MPC5567 microprocessor of the Freescale semiconductor. To verify the developed FlexRay driver, the waveform of the FlexRay driver was measured and compared with the CAN communication system. As a result, the bus load is reduced about 13% compared with the CAN communication system.

DSRC 기반의 T/C 무선통신 시스템 개발 (Wireless Communication System for T/C based on DSRC)

  • 성창우;강대성
    • 한국항만학회지
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    • 제14권3호
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    • pp.313-319
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    • 2000
  • In this paper, we proposed the model of wireless communication for ACTS using DSRC and the DSRC system for T/C. The proposed wireless communication model is how to join with DSRC and other wireless communication in port. The DSRC system for T/C is the first application to the unit of port Facilities Automation on stacking area. The DSRC system is communicated between OBE and RSE using 5.8Hz ISM band frequency. The previous works of DSRC applications are gate automation. In these cases, the road trackers are difficult to obtain information of the port in the stacking area. So we used the DSRC for the wireless communication for the port Facilities Automation. Using DSRC, the load trackers obtain more information in the port and contacts to ITS on back-roads of port. The proposed communication system is serviced to reelection of port statistics.

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이조말통신제도의 역사적 고찰 (A Historical Study of the Communication System in the Later Part of the Lee-Dynasty)

  • 신상각
    • 한국통신학회논문지
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    • 제3권1호
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    • pp.8-17
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    • 1978
  • The later part of the Lee-Dynasty was a period that marked an important turning point in the history of the modern communication system in our country. This paper proposes to research the historic process of initiation and development of the modern communication system in that period through the communication administrative organ and the installation of the wire communication lines such as wastward lines, southward lines and northward lines extended from Han Seung (Seoul) as well as the submarine cables from Korea to Japan. The modernization of the communication system in our country had been achieved in the struggle of national uprising spirits of Korean people against the invasive avarices of the neighbouring nations such as Japan and China. The initiation of the modern communication system played a leading role in civilizing our country. Thus the fair spirits of our forerunners who had schemed to develop the independent communication system should be valued enormously.

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전력선 통신을 이용한 plant 감시 제어 시스템 (Spread Spectrum Method based Power Line Communication for Plant Monitoring and Control System)

  • 서민상;성석경;안병규
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1997년도 전력전자학술대회 논문집
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    • pp.211-215
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    • 1997
  • Localized communication networks for office automation, security monitoring, environmental management of buildings, computer communications, and other applications enjoy every increasing demand. This paper proposes a direct sequence spread spectrum communication system for use in power line data transmission. Advantages of power distribution circuits include reasonably universal coverage and easy access vis a standard wall plug. Disadvantages include limited communication bandwidth, relatively high noise levels, and varying levels of impedance, noise, and attenuation. Spread spectrum signalling provides immunity to narrow-band signal impairments and multiplexing capability. Our prototype power line communication module supports completely physical and data link layers based on the international standard ISO 10368 for reliable high-speed power line communication system. Moreover it provides useful functions to compose a plant monitoring and control system. All the circuits of the communication module are included in one compact circuit. Thus a functional communication system for the power line plant monitoring and control is implemented.

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