• Title/Summary/Keyword: green communications

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Blue-Green Laesrs and Their Application to Undrewater Communication (청록섹 레이저의 수중통신 응용)

  • 김용평;최종운
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.16 no.12
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    • pp.1211-1218
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    • 1991
  • The under water communication which use blue green lasers reviewed. In the view point of absorption and scattering, the optical characteristics of sea water are described. In addition, state of blue green lasers for under water communication are summarized.

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Implementation of The LED illuminance control IP based on 8bit RISC Processor (8bit RISC 프로세서를 이용한 LED Array의 조도제어 IP 구현)

  • Oh, Eun-Tack;Moon, Chul-Hong
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.603-604
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    • 2008
  • This paper implemented The LED illuminance control IP based on 8bit RISC Processor. 8bit RISC Processor designed hardware interrupts, an interface for serial communications, a timer system with compare-capture-reload resources and a watchdog timer. LED Array consists of Red, Green, Blue, White and Warm White. The illuminance control IP is used to LED Board control with 8bit data.

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QoS Buffer Management of Multimedia Networking with GREEN Algorithm

  • Hwang, Lain-Chyr;Ku, Cheng-Yuan;Hsu, Steen-J.;Lo, Huan-Ying
    • Journal of Communications and Networks
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    • v.3 no.4
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    • pp.334-341
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    • 2001
  • The provision of QoS control is a key of the successful deployment of multimedia networks. Buffer management plays an important role in QoS control. Therefore, this paper proposes a novel QoS buffer management algorithm named GREEN (Global Random Early Estimation for Nipping), which extends the concepts of ERD (early random drop) and RED (random early detection). Specifically, GREEN enhances the concept of "Random" to "Global Random" by globally considering the random probability function. It also enhances the concept of "Early" to "Early Esti mation" by early estimating the network status. For performance evaluation, except compared with RED, extensive simulation cases are performed to probe the characteristics of GREEN.

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Service Scenarios for Green House Gas Monitoring Service over NGN

  • Choi, Sam-Gil;Kim, Dong-Il;Lee, Soong-Hee
    • Journal of information and communication convergence engineering
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    • v.9 no.4
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    • pp.401-404
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    • 2011
  • Considerations for green house gas (GHG) monitoring over next generation network (NGN) are regarded as a green convergence service for the successful reduction of GHG emission leading to resolve global warming issue in that NGN is expected to provide secure connections to fixed-and-mobile converged (FMC) features. Model-based scenario approach is an appropriate way to standardize and actualize the desired service. This paper first describes the service scenario of GHG monitoring service over NGN.

Edgeworth Expansion and Bootstrap Approximation for Survival Function Under Koziol-Green Model

  • Kil Ho;Seong Hwa
    • Communications for Statistical Applications and Methods
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    • v.7 no.1
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    • pp.233-244
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    • 2000
  • Confidence intervals for survival function give useful information about the lifetime distribution. In this paper we develop Edgeworkth expansions as approximation to the true and bootstrap distributions of normalized nonparametric maximum likelihood estimator of survival function in the Koziol-Green model and then use these results to show that the bootstrap approximations have second order accuracy.

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ITU-T의 그린ICT 표준화 현황과 전망

  • Kim, Hyeong-Jun;Im, Jeong-Il
    • Information and Communications Magazine
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    • v.29 no.6
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    • pp.22-27
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    • 2012
  • 전 세계적인 기후변화에 대한 관심 고조로, 이에 대한 대응 방안으로서 그린 ICT 관련 기술 개발이 진행되고 있다. 그린 ICT 관련 기술 개발과 함께 해당 기술의 국제표준화가 ITU-T를 비롯해 ISO, IEC, ISO/IEC JTC 1 등 국제 표준화 기구와 ETSI, ATIS, Ecma International, GHG Protocol, The Green Grid, GreenTouch등 지역표준화 기구 및 사실 표준화 기구를 통해 진행되고 있다. 이에 본고에서는 그린ICT의 의미를 살펴보고, ITU-T의 주요 표준화 그룹들의 그린 ICT 표준화 현황과 전망에 대해 소개한다.

Power Quality Measurement for LED-based Green Energy Lighting Systems (LED 기반 그린에너지 조명시스템을 위한 전력품질 측정)

  • Yu, Hyung-Mo;Choi, Jin-Won;Choe, Sangho
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.2
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    • pp.174-184
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    • 2013
  • For the successful R&D and deployment of LED-based green energy lighting systems, the real-time power quality measurement of both various non-linear power signals including pulse waveform, spike waveform, etc and the undesired-signals including harmonics, sag, swell, etc is required. In this paper, we propose a low-cost power quality measurement (PQM) method for low- (60Hz-several KHz) to high-frequency (several tens KHz) power signals, which are generated by green-energy lighting systems, and implement a PQM testbed using TI TMS320F28335 MCU. The proposed algorithm is programmed using C in the CCS (Code Composer Studio) 3.3 environment and is verified using test signals generated by an arbitrary signal generator, NF-WF1974. In the implemented testbed, we can measure various non-linear current signals that LED SMPS generates, analyze harmonics by fast Fourier transform, and test sag, swell, and interruption using wavelet transform.

Reduction Effect of CO2 Discharge of Green PC (그린 PC의 탄소(CO2) 배출량 감축효과)

  • Kim, Young-Geil
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.39C no.2
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    • pp.115-121
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    • 2014
  • Since the rapid development of information age and information technology might be considered to cause environmental problems, Green IT is perceived as core technology for low carbon green growth and the minimum waste of electricity. In this vein, Green IT is becoming new paradigm of focusing on natural environment. This study examines current various IT required for green growth, and studies various methods for diminution of carbon discharge in Korea and other countries. Especially, it focuses on the diminution effect of carbon discharge by using Green PC, and compares the difference of voltage, voltaic current, and the use of electricity between Normal PC and Green PC by using HPM-300A, and measures carbon discharge of Normal PC and Green PC. The result shows that the diminution effect of $CO_2$ discharge of Green PC is amount to 11.5Kg per year, and the effect of green growth is up to the conservation of 2 or 3 pine trees.