• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.5
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• pp.137-147
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• 2008

Recently, Power and thermal management are becoming major concerns in computer system design. The energy efficiency is an important attribute of the mobile and embedded systems. Today's powerful mobile processors needs more energy and longer battery life. Many research has been focused to reduce energy consumption for the mobile processors.In this paper, performance monitoring system for the Power-management techniques is implemented for Intel's XScale microarchitecture-based Marvell PXA320 processor on Windows CE platform. It also provides software interface for changing DVFS configuration. Performance and power consumption are measured for benchmark programs through performance counter value and voltage/current measurements on LabVIEW platform. By using the developed monitoring system, it is possible for dynamic power management to track processor's workload and to determine the actual power consumption.

• Journal of Internet of Things and Convergence
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• v.6 no.2
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• pp.11-18
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• 2020

Since the end devices of the Internet of Things (IoT) are battery operated products, careful consideration for ultra-low power (ULP) is required. The Micro Controller Unit (MCU) industry has developed very effective functions to save energy, but developers have difficulty in selecting the MCU because various operating modes are applied to reduce energy consumption by manufacturers. Therefore, this paper introduces ULPMark benchmark, a standardized benchmark method that can compare MCUs of various vendors and feature sets, and provides hardware functions for ultra-low-power operation of the two platforms that received the high evaluation scores from ULPMark. In addition, we investigated and analyzed how developers can utilize the functions for ultra low power consumption through driver APIs and detailed register control.

• The Journal of the Korea Contents Association
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• v.9 no.8
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• pp.64-72
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• 2009

AMR(Automatic Meter Reading), which means that it reads the meter of electricity, gas, or water, etc at a remote place automatically through wired or wireless communication, has been studied in terms of Power Line Communication method and Local Area Wireless Communication method, etc. In this paper, we designed and implemented JCA(Java Card for AMR) capable of AMR, which is based on java Card technology indispensable to the ubiquitous world. In this paper, JCA follows standard transactional procedures offered by power supply company and manages power usage log and billing data, and is designed in order to satisfy EMV multi-functional specifications. Because JCA is a multi-functional smart card capable of post-issuance applets as an open platform, it is installed into other applications of affiliated concerns as well as credit card and traffic card applications. Not only the proposed JCA is a low cost system, compared to other AMR systems, but is capable of paying rates in advance or later by applying authentication and security function of java Card. In addition the proposed JCA system can create value added services such as affiliated services with corporate alliance.

• Environmental and Resource Economics Review
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• v.13 no.2
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• pp.271-300
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• 2004

We investigate the two recent simulations of the proto-type domestic carbon emission trading system in Korea and draw some policy implications. The first simulation includes the 5 electric power companies based on baseline and credit. But the second one is with the 7 energy-intensive companies based on cap and trade. The voluntary approaches in this paper revealed the instability of market equilibrium, i.e., price volatility or distortion, excess supply or demand. These phenomena stems from excess incentives to the players, asymmetric information, players' irresponsible strategic behaviors, and non acquaintance of trading system. This paper suggests the basic design for domestic carbon trading system in future and a stepwise introduction strategy for it including the incentive auction scheme, the total quantity of incentive needed, and how to finance it. Meantime, the further simulations on the various sectors based on voluntary participation must be essential for learning experiences and better policy design.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.10a
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• pp.584-585
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• 2021

As the production of new and renewable energy such as solar and wind power has diversified, microgrid systems that can simultaneously produce and consume have been introduced. In general, a decrease in electricity prices through solar power is expected in summer, so producer protection is required. In this paper, we propose a transparent and safe gift power transaction system between users using blockchain in a microgrid environment. A futures is simply a contract in which the buyer is obligated to buy electricity or the seller is obliged to sell electricity at a fixed price and a predetermined futures price. This system proposes a futures trading algorithm that searches for futures prices and concludes power transactions with automated operations without user intervention by using a smart contract, a reliable executable code within the blockchain network. If a power producer thinks that the price during the peak production period is likely to decrease during production planning, it sells futures first in the futures market and buys back futures during the peak production period to make a profit in the spot market. losses can be compensated. In addition, if there is a risk that the price of electricity will rise when a sales contract is concluded, a broker can compensate for a loss in the spot market by first buying futures in the futures market and liquidating futures when the sales contract is fulfilled.

• Electric Engineers Magazine
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• s.334
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• pp.30-35
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• 2010

본 고에서는 현장에 설치된 태양광발전시스템의 출력 측정 방법을 제시 하였다. 태양광발전시스템은 햇빛이라는 자연조건에 따라서 출력이 수시로 변동하기 때문에 태양전지 제조자가 제시하는 규격은 제작시에 태양전지를 표준 시험조건(즉, STC, Air Mass 1.5, 일사량 1000[$W/m^2$], 온도 $25^{\circ}C$기준)에서 시험한 성능 규격을 제시하고 있다. 그러나 적용현장에 설치된 태양전지는 인위적으로 표준 시험조건을 만들어 줄 수 없기 때문에 출력을 측정하면 제조자가 제시한 성능 규격이 제대로 나오는지 여부가 관심사다. 그렇기 때문에 설치현장에서 자연 조건에서 측정된 출력에다 태양전지 제작사에서 제시한 온도 및 일사량 특성곡선에서 추출된 보정계수를 적용하여 보정 출력을 산정해서 보정 출력을 토대로 제조사에서 제시한 규격에 부합하는 지 여부를 판단할 수 있는 방법을 제안하였다.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.75-80
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• 2001

EMTDC가 FACTS 기기와 같이 전력전자소자가 포함된 계통을 신뢰성 있게 해석 할 수 있고 또한 다양한 제어기능과 각종 스위칭 소자 모델을 제공 하기때문에 실계통에서 운용되고 있는 서대구 SVC 제어시스템을 EMTDC로 개발하였다. 모델 개발을 위하여 서대구 SVC의 제작사인 ABB에서 제공한 서대구 SVC의 기능, 구성 및 특성을 분석하였으며 개발된 EMTDC SVC 제어시스템 모델의 신뢰성을 검증하기 위하여 제작사에서 제공한 TNA 테스트 결과와 비교하여 모델의 정확성을 검증하였다.

• Annual Conference of KIPS
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• 2013.05a
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• pp.769-772
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• 2013

최근 미국의 enphase사의 상용화를 시작으로 국내에서도 태양광 마이크로 인버터의 개발이 활성화 되고 있다. 이러한 동향은 전기를 분산발전함으로써 고장진단 및 발전성능향상에 크게 기여 할 수 있을 것으로 기대된다. 인버터 용량을 줄여 전력생산을 분산 처리하는 것은 음영으로 인한 발전량 감소, 발전량의 향상을 가져올 수는 있지만 분산 된 처리만큼 데이터의 처리 양을 급격히 증가시킬 수 있다. 본 연구에서는 인버터 제조사 별로 대용량 인버터와 마이크로 인버터사이의 통신프로토콜을 분석하여 패킷의 수를 측정하고 이에 따른 데이터에 대한 상관관계를 분석하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.2B
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• pp.145-150
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• 2002

This paper presents an implementation methodology of unified PCS base station system which, is capable of providing PCS services for 3 PCS carriers concurrently. We have built up an unified PCS BTS using a unification module, which is consisted of a multi-channel combiner, duplexer, LNA, power divider, feeder line, and a common set of antennas. PCS unification module is featured with wide-band and high power handling capability and electrical characteristics like insertion loss, isolation have been greatly improved. It was shown that performance of the system in terms of Ec/Io and mobile receive power within the total 30MHz PCS frequency range is uniformly acceptable and measured signal quality and coverage are equivalent to that of the individual PCS base station.

• 열병합발전
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• s.22
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• pp.3-3
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• 2001

우리협회에서는 2001, 상반기 열병합발전 기술세미나(제어분야)를 지난 5월 24일 동서 발전(주) 호남화력발전처 강당에서 개최하였음. 이번 세미나의 주제는 한국전력연구원과 LG산전(주)이 산학협동으로 연구개발하여 호남화력발전처에 설치한 보일러 제어시스템의 이론 및 현장운영에 관한 내용으로서 발표진은 동 시스템에 참여하였던 과장급 실무진으로 구성하였음. 이번 세미나에서는 11개 회원사 21명을 비롯, 열병합발전 시설보유 및 관련업체 등 17개사 33명의 제어분야 담당자들이 참석하여 새로운 시스템에 대한 높은 관심으로 많은 질의, 응답이 있었음.