• 제목/요약/키워드: Sub-Station

검색결과 537건 처리시간 0.029초

휴리스틱 탐색기법에 근거한 철도입환진로의 자동결정전략 설계 (Strategies for the Automatic Decision of Railway Shunting Routes Based on the Heuristic Search Method)

  • 고윤석
    • 대한전기학회논문지:시스템및제어부문D
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    • 제52권5호
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    • pp.283-289
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    • 2003
  • This paper proposes an expert system which can determine automatically the shunting routes corresponding to the given shunting works by considering totally the train operating environments in the station. The expert system proposes the multiple shunting routes with priority of selection based on heuristic search strategy. Accordingly, system operator can select a shunting route with the safety and efficiency among the those shunting routes. The expert system consists of a main inference engine and a sub inference engine. The main inference engine determines the shunting routes with selection priority using the segment routes obtained from the sub inference engine. The heuristic rules are extracted from operating knowledges of the veteran route operator and station topology. It is implemented in C computer language for the purpose of the implementation of the inference engine using the dynamic memory allocation technique. And, the validity of the builted expert system is proved by a test case for the model station.

Delay Tolerant Packet Forwarding Algorithm Based on Location Estimation for Micro Aerial Vehicle Networks

  • Li, Shiji;Hu, Guyu;Ding, Youwei;Zhou, Yun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권3호
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    • pp.1377-1399
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    • 2020
  • In search and rescue mission, micro aerial vehicles (MAVs) are typically used to capture image and video from an aerial perspective and transfer the data to the ground station. Because of the power limitation, a cluster of MAVs are required for a large search area, hence an ad-hoc wireless network must be maintained to transfer data more conveniently and fast. However, the unstable link and the intermittent connectivity between the MAVs caused by MAVs' movement may challenge the packet forwarding. This paper proposes a delay tolerant packet forwarding algorithm based on location estimation for MAV networks, called DTNest algorithm. In the algorithm, ferrying MAVs are used to transmit data between MAVs and the ground station, and the locations of both searching MAVs and ferrying MAVs are estimated to compute the distances between the MAVs and destination. The MAV that is closest to the destination is selected greedy to forward packet. If a MAV cannot find the next hop MAV using the greedy strategy, the packets will be stored and re-forwarded once again in the next time slot. The experiment results show that the proposed DTNest algorithm outperforms the typical DTNgeo algorithm in terms of packet delivery ratio and average routing hops.

다중 대역용 차세대 이동통신 기지국 시스템의 전력 및 탄소배출량 절감효과 분석 (The Analysis of Reducing Power Consumption and CO2 Emission in the Advanced Mobile Communication Base Station)

  • 오승곤;안준오;김부균
    • 한국통신학회논문지
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    • 제36권6B호
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    • pp.642-649
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    • 2011
  • 본 논문은 다중 대역에서 동작하는 안테나를 장착한 차세대 이동통신 기지국 시스템의 도입 가능성 분석을 위해 종래의 기지국 시스템과 케이블 손실전력을 고려한 차세대 기지국 시스템의 전력 손실 및 탄소 절감효과를 분석하였다. 차세대 기지국 시스템은 옥외에 무선처리부를 설치하고, 옥내의 기저대역처리부는 광케이블로 연결하여 종래의 기지국에서 케이블로 인해 발생하는 전력손실을 없애는 구조이다. 본 연구 결과 종래의 기지국과 비교하여 동일한 서비스 커버리지 확보가 가능하고, 케이블 전력손실이 5 dB 줄어든 차세대 기지국 시스템을 도입할 경우 CDMA 20W, WCDMA 30W, WiBro 10W 기지국에서 소모하는 전력량은 연간 155,078 MWh에서 49,038 MWh로 감소시킬 수 있으며, 탄소배출량 또한 65,878 $tCO_2$에서 20,832 $tCO_2$로 절감됨을 확인하였다. 따라서 차세대 기지국 시스템은 그린 IT 기술로 이용 가능할 것으로 고찰되었다.

Temperature Dependent Octahedral Tilting Behaviors of Monoclinic and Tetragonal SrRuO3 Thin Films

  • Lee, Sung Su;Seo, Okkyun;Kim, Jaemyung;Song, Chulho;Hiroi, Satoshi;Chen, Yanna;Katsuya, Yoshio;Sakata, Osami
    • Journal of the Korean Physical Society
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    • 제73권10호
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    • pp.1529-1534
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    • 2018
  • We used in-situ synchrotron X-ray scattering to investigate phase transformations of octahedral tilted monoclinic $SrRuO_3$ (MSRO) and tetragonal SRO (TSRO) thin films on $SrTiO_3$ (STO) substrates. The octahedral tilted MSRO thin films were highly crystalline and the monoclinic distortion angle was $0.45^{\circ}$. The phase transition temperature from the MSRO to TSRO phase occurred at approximately $200^{\circ}C$ as a second order transition. Conversely, no phase transformations of the TSRO thin film occurred within the range from RT to $250^{\circ}C$. The octahedral $RuO_6$ rotation was strongly affected by the phase transformation in the SRO thin films.

Local dynamic buckling of FPSO steel catenary riser by coupled time-domain simulations

  • Eom, T.S.;Kim, M.H.;Bae, Y.H.;Cifuentes, C.
    • Ocean Systems Engineering
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    • 제4권3호
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    • pp.215-241
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    • 2014
  • Steel catenary riser (SCR) is a popular/economical solution for the oil/gas production in deep and ultra-deep water. The behavioral characteristics of SCR have a high correlation with the motion of floating production facility at its survival and operational environments. When large motions of surface floaters occur, such as FPSO in 100-yr storm case, they can cause unacceptable negative tension on SCR near TDZ (touch down zone) and the corresponding elastic deflection can be large due to local dynamic buckling. The generation, propagation, and decay of the elastic wave are also affected by SCR and seabed soil interaction effects. The temporary local dynamic buckling vanishes with the recovery of tension on SCR with the upheaval motion of surface floater. Unlike larger-scale, an-order-of-magnitude longer period global buckling driven by heat and pressure variations in subsea pipelines, the sub-critical local dynamic buckling of SCR is motion-driven and short cycled, which, however, can lead to permanent structural damage when the resulting stress is greatly amplified beyond the elastic limit. The phenomenon is extensively investigated in this paper by using the vessel-mooring-riser coupled dynamic analysis program. It is found that the moment of large downward heave motion at the farthest-horizontal-offset position is the most dangerous for the local dynamic buckling.

Prostaglandin A2 triggers a strong oxidative burst in Laminaria: a novel defense inducer in brown algae?

  • Zambounis, Antonios;Gaquerel, Emmanuel;Strittmatter, Martina;Salaun, Jean-Pierre;Potin, Philippe;Kupper, Frithjof C.
    • ALGAE
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    • 제27권1호
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    • pp.21-32
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    • 2012
  • We report an oxidative burst triggered by prostaglandin $A_2(PGA_2)$ in the brown algal kelp Laminaria digitata, constituting the first such discovery in an alga and the second finding of an oxidative burst triggered by a prostaglandin in a living organism. The response is more powerful than the oxidative burst triggered by most other chemical elicitors in Laminaria. Also, it is dose-dependent and cannot be inhibited by diphenylene iodonium, suggesting that another source than NAD(P)H oxidase is operational in the production of reactive oxygen species. Despite the very strong oxidative response, rather few effects at other levels of signal transduction pathways could be identified. $PGA_2$ does not increase lipolysis (free fatty acids) in Laminaria, and only one oxylipin (15-hydroxyeicosatetraenoic acid; 15-HETE) was found to be upregulated in Laminaria. In a subsequent set of experiments in the genome model Ectocarpus siliculosus, none of 5 selected candidate genes, all established participants in various stress responses, showed any significant differences in their expression profiles.

소방서 실내공간의 화학적 유해인자 2차노출과 실내공기질 특성 (Characterization of Secondary Exposure to Chemicals and Indoor Air Quality in Fire Station)

  • 김수진;함승헌;전정석;김원
    • 한국화재소방학회논문지
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    • 제33권4호
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    • pp.140-151
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    • 2019
  • 본 연구에서는 소방관들이 화재현장에서 복귀 후 소방청사 내에서 2차적으로 노출된 화학적 유해물질의 실내공기질을 평가하였다. 서울시에 소재한 4개 소방서를 선정하였고, 그 중 2개 소방서는 실제 화재현장에서 소방활동 종료 귀소 후에, 다른 2개 소방서는 대조군으로 설정하여 출동과 상관없이 평소 수준의 실내공기질을 측정하였다. 소방안전지도 전산시스템을 이용하여 서울시에서 발생하는 모든 화재사고에 대하여 24시간 모니터링을 실시하였고 중급규모 이상의 사고에서 실험군이 출동하게 되는 경우 귀소 후 바로 실내공기질을 측정하였다. 11개 유해물질 항목(미세먼지, 포름알데히드, 휘발성유기화합물, PAH, VCM, 산류, 석면, CO, CO2, NO2, O3)을 공정시험법에 따라 측정하였다. 유해물질 11종 중 3종이 국내·외 기준을 초과하였고 1종은 국외기준에 육박하는 것으로 확인되었다. 특히 총휘발성 유기화합물, 이산화탄소, 황산은 각 2.5배, 2.2배, 1.1배가 환경부 및 고용노동부 기준보다 높았다. 또한, 포름알데히드와 황산의 경우, 실험군보다 대조군에서 더 높게 측정되었다. 본 연구결과는 서울특별시 소방청사 내 실내공기질 개선 정책에 활용될 수 있을 것이다.

양파와 파간의 종간잡종 F1과 여교잡계통의 핵 DNA 함량 (Variation of Nuclear DNA Content in Interspecific Allium cepa L.×A. fistulosum L. hybrids and Their Successive Backcross Lines)

  • 김철우;김화영;이을태;최인후;방진기
    • 한국육종학회지
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    • 제41권4호
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    • pp.463-467
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    • 2009
  • Allium 속 근연종인 파와 양파간 종간교잡을 이용하여 양파로부터 새로운 형질을 도입하는 과정에서 유래되는 종간교잡 F1과 여교잡 세대들의 게놈크기의 변화를 flow cytometry를 이용하여 측정한 결과 다음과 같은 결과를 얻었다. 1. 양파와 파의 종간교잡 F1의 식물학적 특성은 양친의 중간형을 보였으나 여교잡이 진전됨에 따라 반복친인 파의 표현형이 우세하였다. flow cytometry를 이용하여 2C nuclear DNA content을 측정한 결과 $F_1$은 양친에 비해 오히려 증가하였으나 여교잡이 진행됨에 따라 급속히 감소하여 $BC_2F_1$에서는 반복친과 비슷한 수준으로 감소하였다. 여교잡세대의 자식인 $BC_1F_2$은 반복친과 비슷한 $23.1{\pm}1.0pg$으로 측정되었으나 $BC_2F_2$$22.9{\pm}0.4pg$으로 반복친의 2C nuclear DNA content인 $23.2{\pm}0.2pg$ 보다 오히려 감소하였다.

Structural, Morphological and Electrical Properties of TiO2 Thin Films Deposited by ALD Method

  • Seung-Yeon Oh;Jae-Min Shin;Gyeong-Hun Na;Min-Seok Kwon;Sang-Jeen Hong;Bumsuk Jung
    • 반도체디스플레이기술학회지
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    • 제22권2호
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    • pp.87-95
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    • 2023
  • TiO2 thin films were grown using the Atomic Layer Deposition (ALD) and their structural and electrical properties were investigated. The crystal structure, dielectric constant, and surface roughness of the TiO2 thin films grown by the ALD deposition method were studied. The grown TiO2 thin films showed an anatase crystal structure, and their properties varied with temperature. In particular, the properties of the TiO2 thin films were confirmed by changing the process temperature. The electrical properties of Metal-Insulator-Silicon (MIS) capacitor structures were analyzed using a probe station. The performance improvement of capacitors using TiO2 as a dielectric was confirmed by measuring capacitance through Capacitance-Voltage (C-V) curves.

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