• Title/Summary/Keyword: digital communication

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A Study on the Open Access of Digital Library (디지털 도서관의 개방 접근에 관한 연구)

  • 이수상
    • Journal of Korean Library and Information Science Society
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    • v.34 no.3
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    • pp.93-110
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    • 2003
  • This paper takes a new open access digital library system to enhancing the process of scholarly communication such as journal publishing, article dissemination, etc. It examines also the causes of crisis in scholarly communication, new alternative models, related activities and case studies. The open access digital library is a practical, cost-effective digital collections capturing and preserving the intellectual output of academic institution including university, research institute.

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Adaptive current-steering analog duty cycle corrector with digital duty error detection (디지털 감지기를 통해 전류 특성을 조절하는 아날로그 듀티 사이클 보정 회로)

  • Choi, Hyun-Su;Kim, Chan-Kyung;Kong, Bai-Sun;Jun, Young-Hyun
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.465-466
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    • 2006
  • In this paper, novel analog duty cycle corrector (DCC) with a digital duty error detector is proposed. The digital duty error detector measures the duty error of the clock and converts it into a digital code. This digital code is then used to accurately correct the duty ratio by adaptively steering the charge-pump current. The proposed duty cycle corrector was implemented using an 80nm DRAM process with 1.8V supply voltage. The simulation result shows that the proposed duty cycle corrector improves the settling time up to $70{\sim}80%$ at 500MHz clock frequency for the same duty correction accuracy as the conventional analog DCC.

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A Study on the Development of the Digital Traffic Signal Controller (디지털 교통신호제어기 개발 연구)

  • Ko, Sejin;Lee, Jaekwan;Park, Sangmin;Gho, Gwang-Yong;Yun, Ilsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.6
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    • pp.43-59
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    • 2019
  • The Traffic controller currently used in Korea is a switch control system that directly transfers 220V of high voltage to traffic lights one to one. This method requires a lot of cables, and there are concerns about electric shock. Accordingly, Korea Road Traffic Authority added the digital communication signal controller standard using digital communication method to the standard specification of the communication signal controller of the National Police Agency. Based on these specifications, this paper intended to develop digital communication call controllers. In addition, it was verified that even if the digital communication signal controller and analogue communication call controller were mixed, they could operate in the signal control system currently in operation.

Digital Speech Coding Technologies for Wire and Wireless Communication (유무선망에서 사용되는 디지털 음성 부호화 기술 동향)

  • Yoon, Byungsik;Choi, Songin;Kang, Sangwon
    • Journal of Broadcast Engineering
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    • v.10 no.3
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    • pp.261-269
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    • 2005
  • Throughout the history of digital communication, the digital speech coder is used as speech compression tool. Nowadays, the speech coder has been rapidly developed in the area of mobile communication system to overcome severe channel error and limitation of radio frequency resources. Due to the development of high performance communication system, high quality of speech coder is needed. This kind of speech coder can be used not only in communication services but also in digital multimedia services. In this paper, we describe the technologies of digital speech coder which are used in wire and wireless communication. We also present a summary of recent speech coding standards for narrowband and wideband applications. Finally we introduce the technical trends of next generation speech coder.

Digital Error Correction for a 10-Bit Straightforward SAR ADC

  • Rikan, Behnam Samadpoor;Abbasizadeh, Hamed;Do, Sung-Han;Lee, Dong-Soo;Lee, Kang-Yoon
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.1
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    • pp.51-58
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    • 2015
  • This paper proposes a 10-b SAR ADC. To increase the conversion speed and reduce the power consumption and area, redundant cycles were implemented digitally in a capacitor DAC. The capacitor DAC algorithm was straightforward switching, which included digital error correction steps. A prototype ADC was implemented in CMOS $0.18-{\mu}m$ technology. This structure consumed $140{\mu}W$ and achieved 59.4-dB SNDR at 1.25MS/s under a 1.8-V supply. The figure of merit (FOM) was 140fJ/conversion-step.

Critical Analysis of ITV Digital in UK (영국 ITV Digital의 실패에 관한 연구)

  • Kim, Seung-Soo
    • Korean journal of communication and information
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    • v.20
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    • pp.7-32
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    • 2003
  • This essay provides a critical introduction to some of the major issues relating to ITV Digital. The demise of ITV Digital has hit the economics of broadcasting industry in UK. ITV Digital's failure is seen as digital nightmare. This study approaches to three dimensions of the failed ITV Digital. There are the failure of policy, business strategy, technological debacle. As I have discussed, competitive environment of digital broadcasting squeezed ITV Digital into financial trouble. In order to examine current development of digital terrestrial television, three questions have been raised. First, What is the government of digital broadcasting? Second, What is the business strategy of ITV Digital? In particular, the failure of business model deserved careful watching. Third, What is the failure of digital technology?

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Design of digital communication systems using DCSK chaotic modulation (DCSK 카오스 변조를 이용한 디지털 통신 시스템의 설계)

  • Jang, Eun-Young
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.5
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    • pp.565-570
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    • 2015
  • Spread spectrum communications have increased interest due to their immunity to channel fading and low probability of intercept. One of the limitations of the traditional digital spread spectrum systems is the need for spreading code synchronization. Chaotic communication is the analogue alternative of digital spread spectrum systems beside some extra features like simple transceiver structures. In this paper, This paper was used instead of the digital modulation and demodulation carriers for use in the chaotic signal in a digital communication system among the chaotic modulation schemes, the Differential Chaos Shift Keying(DCSK) is the most efficient one because its demodulator detects the data without the need to chaotic signal phase recovery. Also Implementation of Differential Chaos Shift Keying Communication System Using Matlab/Simulink and the receiver con decode the binary information sent by the transmitter, performance curves of DCSK are given in terms of bit-error probability versus signal to noise ratio with spreading factor as a parameter and we compare it to BPSK modulation.

Analysis of Nonlinear Behavior for Addiction in Digital Sport (디지털 스포츠 중독의 비선형 거동 해석)

  • Bae, Young-Chul
    • The Journal of the Korea institute of electronic communication sciences
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    • v.12 no.5
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    • pp.977-982
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    • 2017
  • Recently, the effort that converge the sport and ICT continues together with developing ICT. The game is a representative example. The digital sport is developing as mixed type that are composed with sport and digital such as screen golf and screen bowling. The addiction problem exist in the digital sport like the addiction problem exist in general sport. In this paper, we propose the addiction model in the digital sport as fractional-order. We represent time series and phase portrait for nonlinear behavior from proposed fractional-order model and we confirms the difference between them.