• 제목/요약/키워드: digital communication system

검색결과 2,536건 처리시간 0.029초

사람-사람, 사람-사물의 대화를 지원하는 인스턴트 메신저 구현 (Implementation of an Instant Messenger Supporting Human-Human and Human-Thing Communication)

  • 최종명
    • 디지털산업정보학회논문지
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    • 제5권1호
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    • pp.1-8
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    • 2009
  • This paper is about the implementation of MyTalk, an instant messaging system, which supports human-human and human-thing communication. It consists of agents which are representatives of communication entities, and agent windows for user interfaces. Users can communicate with their buddies, and monitor and control remote "things" and devices with MyTalk. We also introduce the concept of agent window, which provides the most suitable GUIs (text, form, graph etc) for communication. Currently, MyTalk supports ordering goods, controlling devices like printers, monitoring sensors, managing applications, and real-time talk. Furthermore, we can extend it to application platform for remote monitoring, remote controlling, and real time cooperation.

산업용 6관절 로봇의 원격제어를 위한 실시간 병렬데이터통신 인터페이스 (Development of Realtime Parallel Data Communication Interface for Remote Control of 6-DOF Industrial Robot)

  • 최명환;이우원
    • 산업기술연구
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    • 제21권A호
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    • pp.97-103
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    • 2001
  • This paper presents the development of the I/O Interface for the real time parallel data communication between controller of a six-axis industrial robot(CRS-A460) and an external computer. The proposed I/O Interface consists of the hardware I/O interface and the software that is downloaded to the robot controller and executed by the controller operating system. The constitution of the digital I/O Port for CRS-A460 robot controller and the digital I/O board for IBM-PC are presented as well as the Process Control Program of the robot controller. The developed protocol for the parallel data communication is described. The data communication is tested, and the performance is analysed. In particular, it is shown that the real-time constraint of the robot controller process is satisfied.

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국제 표준을 준수하는 웹 전자 공증 시스템의 개발 (Development of a Web-based Digital Notary System Conforming International Standards)

  • 장혜진
    • 한국산학기술학회논문지
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    • 제5권1호
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    • pp.16-20
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    • 2004
  • 본 논문은 보안적으로 안전하며, 타임스탬프 관련 국제 표준 규격을 만족하며, 사용자 접근성이 높은 웹 기반 시스템 형태를 갖는 전자 공증 시스템(digital notary system)을 개발하였다. 타임스탬프 관련 기술 및 응용 시스템들은 아직 대중화되어 있지 않지만 전자상거래, 디지털 저작권 관리, 인터넷 메일 등의 다양한 분야에서 잠재적으로 매우 중요한 의미를 갖는다. 개발된 전자 공증 시스템은 rfc3161을 준수하는 타임스탬프 요청(timestamp request) 및 타임스탬프 응답(timestamp response)을 사용한다. 또한 서버와 클라이언트 통근에 SSL(Secure Socket Layer)을 사용하여 통신 보안을 보장하며, 재사용공격(replay attack)을 방지하기 위하여 논스(nonce)를 사용한다.

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전력선 통신 기반 전관방송 시스템 (Power Line Communication Based Public Address System)

  • 김석;김대익
    • 한국전자통신학회논문지
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    • 제12권6호
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    • pp.1035-1042
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    • 2017
  • 본 논문에서는 복잡한 전관방송 장비와 케이블을 용이하게 운용하고, 확장 및 증설할 수 있도록 전력선 통신을 이용한 전관방송 시스템을 개발하였다. 전력선 통신 기반 전관방송 시스템은 디지털 스트리밍 변조 방식을 적용한 제어 보드와 스피커 보드로 구현되었으며, 오디오 최대 출력, 오디오 채널 응답 시간, 오디오 출력 SNR, 그리고 오디오 출력 THD+N에 대한 성능 측정을 실시하여 만족스러운 결과를 확인할 수 있었다.

USN기반 참여형 조명에너지 관리시스템 (Management System of USN-based Collaborative Lighting Energy)

  • 김삼택
    • 한국인터넷방송통신학회논문지
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    • 제13권4호
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    • pp.47-53
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    • 2013
  • 현재 조명의 효율화 및 제어시스템 개선을 통해 에너지절감을 추진한다는 계획을 수립하고 조명자체의 고효율화와 조명제어시스템의 성능 향상을 통해 에너지 절감을 추구하는 노력이 한층 강화될 것으로 보인다. 조명시스템에서 LED를 광원으로 사용할 경우 기존 대비 약 50% 이상의 고효율 조명 구현이 가능하다. 본 논문은 LED 디지털 조명을 제어하기 위해 USN을 활용해 유무선 통신을 지원하는 스마트 디머 와 스마트 스위치를 적용한 LEMS(Lighting Energy Management System)를 개발했다. 이 시스템은 유/무선 네트워킹 장치 및 시스템 S/W를 통해 실내외 조명 및 경관 조명을 포함한 특수 목적 등을 효율적이고 신뢰성 있게 제어 한다. 본 시스템은 LED조명의 Digital System Lighting을 통한 USN 원격통합제어기능 및 에너지 효율성을 증대하여 실내외의 조명에너지 사용량을 최소화 하고, 웹 또는 스위치를 통해 조명 에너지 사용량을 사용자가 측정하여 조명 사용량을 피드백 할 수 있게 하는 참여형 시스템이다.

CDMA2000 시스템에서 파일럿 채널을 이용한 스마트 안테나 시스템의 성능향상 연구 (Research on Improving Performance Utilizing Pilot Channel of Smart Antenna System in CDMA2000 system)

  • 안성수;김민수
    • 디지털산업정보학회논문지
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    • 제5권3호
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    • pp.99-105
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    • 2009
  • This paper suggests novel signal processing methods for optimal beamforming of smart antenna system in CDMA2000 mobile communication environments. This method utilize characteristics of the reverse pilot channel of CDMA2000 mobile communication systems, and applies them to improve the performance of an adaptive algorithm, which is used to a smart antenna system for beamforming. To perform the best beamforming, it is important to get an exact beamforming algorithm. This paper proposed an algorithm based on Laglange multiplier which has such an adaptive process, and also proposed the method to demodulate the received signal through array antenna using pilot channel in CDMA2000 environment. This paper analysed the enhanced performance of proposed algorithm in various signal environment through signal modeling of physical layer in CDMA2000 reverse link.

고품질 컬러인쇄물의 색 교정 시스템 개발에 관한 연구 (A Study on the Color Proofing System Development for High Quality Color Prints)

  • 송경철;강상훈
    • 한국인쇄학회지
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    • 제22권2호
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    • pp.55-72
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    • 2004
  • The term color management system design, an ensemble of algorithm that provides a framework in which color information can be processed consistently throughout a digital imaging system. This is most commonly achieved through the use of special color transformation, known as device independent color transformation based on ICC device profiles. The purpose of this paper is to present some of the scientific principles of color management, and the original color management algorithms and solutions for digital soft color proofing system development.

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Modeling of a Continuous-Time System with Time-delay

  • Park, Jong-Jin;Choi, Guy-Seok
    • International Journal of Internet, Broadcasting and Communication
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    • 제4권2호
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    • pp.1-6
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    • 2012
  • Control Theory for continuous-time system has been well developed. Due to the development of computer technology, digital control scheme are employed in many areas. When delays are in control systems, it is hard to control the system efficiently. Delays by controller-to-actuator and sensor-to-controller deteriorate control performance and could possibly destabilize the overall system. In this paper, a new approximated discretization method and digital design for control systems with multiple state, input and output delays and a generalized bilinear transformation method with a tunable parameter are also provided, which can re-transform the integer time-delayed discrete-time model to its continuous-time model. Illustrative examples are given to demonstrate the effectiveness of the developed method.

Development of Structured Light 3D Scanner Based on Image Processing

  • Kim, Kyu-Ha;Lee, Sang-Hyun
    • International Journal of Internet, Broadcasting and Communication
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    • 제11권4호
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    • pp.49-58
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    • 2019
  • 3D scanners are needed in various fields, and their usage range is greatly expanded. In particular, it is being used to reduce costs at various stages during product development and production. Now, the importance of quality inspection in the manufacturing industry is increasing. Structured optical system applied in this study is suitable for measuring high precision of mold, press work, precision products, etc. and economical and effective 3D scanning system for measuring inspection in manufacturing industry can be implemented. We developed Structured light 3D scanner which can measure high precision by using Digital Light Processing (DLP) projector and camera. In this paper, 3D image scanner based on structured optical system can realize 3D scanning system economically and effectively when measuring inspection in the manufacturing industry.

Effects of Digital Elevation Model in Water Quality Modeling using Geogrpahic Information System

  • Cho, Sung-Min
    • International Journal of Internet, Broadcasting and Communication
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    • 제13권2호
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    • pp.14-19
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    • 2021
  • Aim of this research was to investigate the effects of Digital Elevation Model (DEM) for sensitivity analysis with two types of DEMs: 1 to 24,000 and 1 to 250,000 DEM. Another emphasis was given to the development of methodology for processing DEMs to create ArcGIS Pro and GRASS layers. This was done while developing water quality system modeling using DEMs which were used to model hydrological processes and SWAT model. Sensitivity analysis with DEMs resulted in different runoff volumes in the model simulation. Runoff volume was higher for the 1:24,000 DEM than 1:250,000 DEM, probably due to the finer resolution and slope which increased the estimated runoff from the watershed. Certainly the DEMs were factors in precision of the simulations and it was obvious during sensitivity analysis that DEMs had significant effect on runoff volumes. We suggest, however, that additional comparative research could be conducted involving more parameters such as soil and hydrologic parameters to provide insight into the overall physical system which the SWAT model represents.