• Title/Summary/Keyword: Power-Saving

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Technical Information in the Field of Illumination and Related Information Sources (조명분야 기술정보와 관련 정보원)

  • Kim, Tae-Seung
    • Journal of Information Management
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    • v.27 no.3
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    • pp.1-24
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    • 1996
  • The purpose of this study is to provide by locating various information sources in illuminating engineering and its related field. The proportion that illumination forms in the total electric power consumption takes up to 18%. For the development of new energy-saving lighting products, it Is indispensable to find out and use related technical information. The result of systematic survey of various information sources will be helpful for the researchers and librarians engaged in the field of illuminating engineering.

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Implementation of Broadband Lightning Signal Detection and Signal Saving System (광대역 낙뢰탐지 및 신호저장 시스템 구현)

  • Lee, Sung-Ho;Sung, Tae-Kyung;Woo, Jung-Wook;Kwak, Ju-Sik
    • Proceedings of the KIEE Conference
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    • 2006.07c
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    • pp.1467-1468
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    • 2006
  • 본 논문에서는 현재 운용되고 있는 낙뢰탐지 시스템들과는 다른 측위방식인 TDOA(Time Difference of Arrival)방법을 사용한 3차원 낙뢰 탐지 및 추적 시스템을 제안한다. TDOA방식은 낙뢰와 수신국사이의 도달시간을 측정하여 두 수신국간의 시간차가 일정한 쌍곡선을 얻고 이들 쌍곡선의 교점을 이용해 낙뢰의 위치를 결정하는 방법이다. 이 시스템을 이용하여 위치정확도가 수 미터인 3차원 낙뢰 방전 궤적을 얻을 수 있다. 시스템의 구현을 위해서 먼저 낙뢰의 신호를 저장해야 하는데, 광대역의 낙뢰신호를 저장하기 위해서는 고속의 디지타이저가 필요하다. 그러나 디지타이저와 프로세서간의 인터페이스의 한계로 연속적으로 이를 저장하는 것은 어려우며, 이러한 신호 저장의 문제점을 해결하기 위해서 낙뢰 신호 저장 시스템이 필요하다. 본 논문에서는 낙뢰의 메커니즘과 광대역 낙뢰신호 검출기법을 설명하고, 구현한 낙뢰 신호 저장 시스템을 소개한다.

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An energy efficient clustering scheme by adjusting group size in zigbee environment (Zigbee 환경에서 그룹 크기 조정에 의한 에너지 효율적인 클러스터링 기법)

  • Park, Jong-Il;Lee, Kyoung-Hwa;Shin, Yong-Tae
    • Journal of Sensor Science and Technology
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    • v.19 no.5
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    • pp.342-348
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    • 2010
  • The wireless sensor networks have been extensively researched. One of the issues in wireless sensor networks is a developing energy-efficient clustering protocol. Clustering algorithm provides an effective way to extend the lifetime of a wireless sensor networks. In this paper, we proposed an energy efficient clustering scheme by adjusting group size. In sensor network, the power consumption in data transmission between sensor nodes is strongly influenced by the distance of two nodes. And cluster size, that is the number of cluster member nodes, is also effected on energy consumption. Therefore we proposed the clustering scheme for high energy efficiency of entire sensor network by controlling cluster size according to the distance between cluster header and sink.

Multi-objective Capacitor Allocations in Distribution Networks using Artificial Bee Colony Algorithm

  • El-Fergany, Attia;Abdelaziz, A.Y.
    • Journal of Electrical Engineering and Technology
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    • v.9 no.2
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    • pp.441-451
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    • 2014
  • This article addresses an efficient heuristic-based approach to assign static shunt capacitors along radial distribution networks using the artificial bee colony algorithm. The objective function is adapted to enhance the overall system static voltage stability index and to achieve maximum net yearly savings. Load variations have been considered to optimally scope the fixed and switched capacitors required. The numerical results are compared with those obtained using recent heuristic methods and show that the proposed approach is capable of generating high-grade solutions and validated viability.

Efficient Processing Scheme for Correlated Data in Ubiquitous Sensor Networks (유비쿼터스 센서 네트워크에서 연관된 데이터의 효율적인 처리방안)

  • Ryu, Jea-Tek;Heo, Nam-Ho;Yoo, Seung-Wha;Kim, Ki-Hyung
    • 한국정보통신설비학회:학술대회논문집
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    • 2008.08a
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    • pp.63-68
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    • 2008
  • In now days, Ubiquitous technology grow up, so the variety service are developed. Sensor networks purpose is collection information about environment and geographic. But sensor network has limit in power, cost and so on. There is much restriction. Some sensor networks purpose is monitoring environment. And there is some relation in sensing data. Sensor nodes sense information by periods. First sensing data correlate with next sensing data. At this point, this paper suggest power saving method. Some data are same, the other data are similar.

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Improvement of Starting Characteristics of Single Phase Induction Motor by Phase Angle Voltage Controller (위상각 전압제어기에 의한 단상유도전동기 기동특성 개선)

  • Lim, Yang-Su;Baek, Hyung-Lae
    • The Transactions of the Korean Institute of Power Electronics
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    • v.1 no.1
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    • pp.20-26
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    • 1996
  • The common drive method of the single phase induction motor(SPIM) is to install a start capacitor and a centrifugal switch in series with the auxiliary winding. In this paper, the phase angle voltage sequence controller is proposed to eliminate a start capacitor and a centrifugal switch of SPIM. In comparison with the capacitor start system of SPIM, the proposed control system shows that it contributes to saving the starting current about 57% and to improving of the starting efficiency of SPIM. The proposed starting characteristics of the SPIM is obtained with this strategy through simulation and experimental results.

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A New Current Sharing Strategy of SRM Using Parallel Winding Method (병렬권선 방식에 의한 SRM의 부하전류분담)

  • 박성준;이동희;안진우;안영주
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.52 no.4
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    • pp.154-154
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    • 2003
  • The switched reluctance motor(SRM) has a considerable potential for industrial applications because of its high reliability as a result of the absence of rotor windings. In some applications with SRM, a parallel switching strategy is often used for cost saving, increasing of current capacity and system reliability. This paper proposes a new parallel switching strategy of SRM using parallel winding. While conventional parallel switching devices are connected in a phase winding, power devices are connected in the parallel windings wound in each pole of stator in the proposed method. Paralleling strategy for current sharing in the proposed method can be easily determined without considerations of any nonlinear characteristics of power devices such as conduction resistance, threshold voltage and gain factor. The proposed paralleling strategy is verified by the mathematical analysis and experimental results.

Speed Control for Low Speed Diesel Engine by Hybrid F-NFC (Hybrid F-NFC에 의한 저속 디젤 기관의 속도 제어)

  • Choi, G.H.;Yang, J.H.
    • Journal of Power System Engineering
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    • v.10 no.4
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    • pp.159-164
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    • 2006
  • In recent, the marine engine of a large size is being realized a lower speed, longer stroke and a small number of cylinders for the energy saving. Consequently the variation of rotational torque became larger than former days because of the longer delay-time in fuel oil injection process and an increased output per cylinder. It was necessary that algorithms have enough robustness to suppress the variation of the delay-time and the parameter perturbation. This paper shows the structure of hybrid F-NFC against the delay-time and the perturbation of engine parameter as modeling uncertainties, and the design of the robust speed controller by hybrid F-NFC for the engine. And, The Parameter values of linear equation are determined by RC-GA for F-NFS. The hybrid F-NFC is combined the F-NFC and PID controller for filling up each.

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Study on the Energy Saving for School Buildings - through thermal effect of the transparent insulated opaque envelopes - (학교건물의 에너지 절약에 관한 연구 - 투명 단열외피의 열적성능을 중심으로 -)

  • Lee, S.;Kim, S.H.;Kim, K.C.
    • Journal of Power System Engineering
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    • v.10 no.1
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    • pp.41-45
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    • 2006
  • The thermal effect of a transparent insulated opake wall with solar energy was investigated theoretically. The heat gain through transparent insulated opake wall was studied for relative simple conditions. The stationary heat transport effect was studied for layer which is built on the opake wall. This study shows that a relative low solar radiation intensity causes a great heat reduction through the transparent insulated opake wall.

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Diagnostic methods applied to Esfahan light water subcritical reactor (ELWSCR)

  • Arkani, Mohammad
    • Nuclear Engineering and Technology
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    • v.53 no.7
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    • pp.2133-2150
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    • 2021
  • In this work, Esfahan light water subcritical reactor (ELWSCR) is analysed using experimental and theoretical diagnostic methods. Important neutronic parameters of the system such as prompt neutron lifetime, delayed neutron fraction, prompt neutron decay constant, negative reactivity of the core, fuel and moderator temperature coefficient of reactivity, and overall and local void coefficient of reactivity are estimated. Also, neutron flux distribution, reflector saving, water level effect, and lattice pitch of the core including operating point of the facility are studied in details. Theoretical results are calculated by MCNPX and measurements are performed utilizing zero power reactor noise method. Detailed descriptions of the results are explained in the text.