• 제목/요약/키워드: Power graph

검색결과 240건 처리시간 0.027초

IED를 기반으로 하는 디지털 수배전반의 지적추론기반 운전제어 솔루션 설계 (The Design of Operation and Control Solution with Intelligent Inference Capability for IED based Digital Switchgear Panel)

  • 고윤석
    • 대한전기학회논문지:전력기술부문A
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    • 제55권9호
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    • pp.351-358
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    • 2006
  • In this paper, DSPOCS(Digital Switchgear-Panel Operation and Control Solution) is designed, which is the intelligent inference based operation and control solution to obtain the safety and reliability of electric power supply in substation based on IED. DSPOCS is designed as a scheduled monitoring and control task and a real-time alarm inference task, and is interlinked with BRES(Bus Reconfiguration Expert System) in the required case. The intelligent alarm inference task consists of the alarm knowledge generation part and the real-time pattern matching part. The alarm knowledge generation part generates automatically alarm knowledge from DB saves it in alarm knowledge base. On the other hand, the pattern matching part inferences the real-time event by comparing the real-time event information furnished from IEDs of substation with the patterns of the saved alarm knowledge base.; Especially, alarm knowledge base includes the knowledge patterns related with fault alarm, the overload alarm and the diagnosis alarm. In order to design the database independently in substation structure, busbar is represented as a connectivity node which makes the more generalized graph theory possible. Finally, DSPOCS is implemented in MS Visual $C^{++}$, MFC, the effectiveness and accuracy of the design is verified by simulation study to the typical distribution substation.

국내 AS 수준 인터넷 위상 분석과 인터넷 위상 생성기 비교에 관한 연구 (A Comparative Study of The Internet Topology Generators for Domestic AS-Level Topology)

  • 오동익;이강원
    • 한국정보통신학회논문지
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    • 제16권11호
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    • pp.2365-2373
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    • 2012
  • 본 논문에서는 UCLA IRL의 BGP 데이터, IRR, IXP 데이터를 이용하여 한국 AS 수준 인터넷 위상 데이터를 구축하였다. 그리고 지금까지 소개된 인터넷 위상 생성 모형(Waxman, BA and GLP)를 이용하여 한국 AS 수준 인터넷과 동일한 노드수를 가지는 위상 데이터를 생성한 뒤, 각각의 모형이 얼마나 한국 AS 수준 인터넷 위상을 잘 묘사하는지 분석하였다. 본 연구를 통해 기존의 인터넷 위상 생성기 모형들은 한국 AS 수준 인터넷을 잘 묘사하지 못하는 것을 확인하였다.

Photovoltaic module의 발전 온도에 따른 EVA 광 특성 연구 (A Study on EVA Optical Characteristics By Generation Temperature of PV module)

  • 우성철;정태희;민용기;강기환;안형근;한득영
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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    • pp.31-35
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    • 2011
  • Photovoltaic modules are well known to be one of the most eco generation of electricity. But usually study solar cell. Otherwise, PV modules are also important in power generation. We have to check other subsidiary materials. In this work benefit of using optically superior encapsulation materials(EVA) in generation temperature is demonstrated. Optical characterization of three EVA products demonstrates reduced transmission in the visible ray region of the solar spectrum. It will have a decisive effect to the module efficiency. Test is shown reduction of reflectance and transmittance. Reflections is dependent on the low iron glass. It can be seen between a specific wave length(240~350mm) about 1%. Transmittance in the entire ray region of light is markedly reduced to depending on the temperature rise. The graph is shown optical properties on EVA. Transmission was reduced. about 1%.

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역방향 CDMA 시스템에서 에너지 최적화된 전송기법: 그래프 이론적 접근 (Energy Optimized Transmission Strategy in CDMA Reverse Link: Graph Theoretic Approach)

  • 오창윤
    • 전자공학회논문지
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    • 제52권6호
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    • pp.3-9
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    • 2015
  • 본 논문에서는 짧은 지연시간을 요구하는 CDMA 시스템 환경에서 전송률 스케줄링과 전력량 할당 문제를 연구한다. 구체적으로, 본 논문은 각각의 단말이 짧은 구간 동안의 평균 전송률을 유지하는 동시에 에너지 효율적인 스케줄링 방안을 제안한다. 다중 코드를 적용한 CDMA 시스템을 고려하며, 각각의 코드는 가상의 사용자로 해석할 수 있다. 논문의 최종 목적은 전송률 과정에서 소모하는 에너지가 최소화되도록 각각의 시간슬럿에 가상의 사용자를 스케줄링하는 방안을 제안하는 것이다. 주목할만한 점은, 본 논문에서 고려하는 전송률 최적화 문제가 최단 경로 알고리즘으로 해결 가능하다는 점이다. 마지막으로, 본 논문이 제안하는 에너지 최적화 스케줄링 방안을 TDMA 형식의 스케줄링 방안과 성능 비교 분석한다.

Constrained Sparse Concept Coding algorithm with application to image representation

  • Shu, Zhenqiu;Zhao, Chunxia;Huang, Pu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권9호
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    • pp.3211-3230
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    • 2014
  • Recently, sparse coding has achieved remarkable success in image representation tasks. In practice, the performance of clustering can be significantly improved if limited label information is incorporated into sparse coding. To this end, in this paper, a novel semi-supervised algorithm, called constrained sparse concept coding (CSCC), is proposed for image representation. CSCC considers limited label information into graph embedding as additional hard constraints, and hence obtains embedding results that are consistent with label information and manifold structure information of the original data. Therefore, CSCC can provide a sparse representation which explicitly utilizes the prior knowledge of the data to improve the discriminative power in clustering. Besides, a kernelized version of our proposed CSCC, namely kernel constrained sparse concept coding (KCSCC), is developed to deal with nonlinear data, which leads to more effective clustering performance. The experimental evaluations on the MNIST, PIE and Yale image sets show the effectiveness of our proposed algorithms.

Strong Roman Domination in Grid Graphs

  • Chen, Xue-Gang;Sohn, Moo Young
    • Kyungpook Mathematical Journal
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    • 제59권3호
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    • pp.515-523
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    • 2019
  • Consider a graph G of order n and maximum degree ${\Delta}$. Let $f:V(G){\rightarrow}\{0,1,{\cdots},{\lceil}{\frac{{\Delta}}{2}}{\rceil}+1\}$ be a function that labels the vertices of G. Let $B_0=\{v{\in}V(G):f(v)=0\}$. The function f is a strong Roman dominating function for G if every $v{\in}B_0$ has a neighbor w such that $f(w){\geq}1+{\lceil}{\frac{1}{2}}{\mid}N(w){\cap}B_0{\mid}{\rceil}$. In this paper, we study the bounds on strong Roman domination numbers of the Cartesian product $P_m{\square}P_k$ of paths $P_m$ and paths $P_k$. We compute the exact values for the strong Roman domination number of the Cartesian product $P_2{\square}P_k$ and $P_3{\square}P_k$. We also show that the strong Roman domination number of the Cartesian product $P_4{\square}P_k$ is between ${\lceil}{\frac{1}{3}}(8k-{\lfloor}{\frac{k}{8}}{\rfloor}+1){\rceil}$ and ${\lceil}{\frac{8k}{3}}{\rceil}$ for $k{\geq}8$, and that both bounds are sharp bounds.

전륜구동 차량용 자동변속기의 기구학적 구성에 대한 조립 가능성 분석에 관한 연구 (Assemblability Analysis of Kinematic Configurations of Front-Wheel Drive Automatic Transmissions)

  • 권현식
    • 한국기계가공학회지
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    • 제18권11호
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    • pp.24-34
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    • 2019
  • An automotive automatic transmission is a popular power-transmitting device in passenger vehicles, as it provides various speed ratios for diverse driving conditions with easy manipulation and smooth gear shifting. The transmission is mainly composed of input and output shafts, planetary gear sets, brakes/clutches, and housing, and it yields multiple forward gears and one reverse gear by actuating the shifting devices of the brakes and clutches. In developing a new transmission, kinematic configurations of a transmission, which presents a brief structure and actuation schemes for speed ratios, need to be checked to determine if the structure can be assembled in a layout. It is impossible for a transmission concept having any interference in connecting main components to be developed further in the design process, since connection interference leads to failure of a layout design in the 2-D plane. In this research, an analysis of the assemblability of a front-wheel drive automatic transmission is carried out on an example concept design by applying the vertex addition algorithm based on graph theory.

인시투 가스 측정이 가능한 경제적 가스 챔버 구현 및 센서 전압에 따른 가스 응답 특성 분석 (Economical Gas Chamber for In-situ Gas Measurement and Analysis of Gas Response Characteristics according to Sensor Voltage)

  • 최연석;이인환
    • 한국기계가공학회지
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    • 제18권5호
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    • pp.1-8
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    • 2019
  • Breath analysis using a portable device is better than the classical breath analysis system in terms of installation and operation. There is an increasing need to develop cost-effective equipment for testing gas sensors from the viewpoint of functionalities that can be applied applicable to portable devices. In the present study, an economical gas chamber for in-situ gas measurement is implemented with a single gas chamber without using expensive gas storage and control equipment; the gas response characteristics are analyzed using the above-described chamber. The main features of the implemented gas chamber are simple injection procedure, improved gas diffusion, easy measurement and cleaning, support for low-power mode measurement function for portable devices, and open source platform. Moreover, an analysis of gas response characteristics based on changes in sensor voltage show that the sensitivity and 90% response time are affected by the sensor voltage. Furthermore, the sensitivity graph has an inflection point in a specific range. The gas sensor applied in this study showed fast response speed and high sensitivity for sensor voltages of 3.0-3.5 V, regardless of the concentration of acetone gas, the target gas used in this study.

Correlation Distance Based Greedy Perimeter Stateless Routing Algorithm for Wireless Sensor Networks

  • Mayasala, Parthasaradhi;Krishna, S Murali
    • International Journal of Computer Science & Network Security
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    • 제22권1호
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    • pp.139-148
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    • 2022
  • Research into wireless sensor networks (WSNs) is a trendy issue with a wide range of applications. With hundreds to thousands of nodes, most wireless sensor networks interact with each other through radio waves. Limited computational power, storage, battery, and transmission bandwidth are some of the obstacles in designing WSNs. Clustering and routing procedures have been proposed to address these concerns. The wireless sensor network's most complex and vital duty is routing. With the Greedy Perimeter Stateless Routing method (GPSR), an efficient and responsive routing protocol is built. In packet forwarding, the nodes' locations are taken into account while making choices. In order to send a message, the GPSR always takes the shortest route between the source and destination nodes. Weighted directed graphs may be constructed utilising four distinct distance metrics, such as Euclidean, city block, cosine, and correlation distances, in this study. NS-2 has been used for a thorough simulation. Additionally, the GPSR's performance with various distance metrics is evaluated and verified. When compared to alternative distance measures, the proposed GPSR with correlation distance performs better in terms of packet delivery ratio, throughput, routing overhead and average stability time of the cluster head.

브레인 모사 인공지능 기술 (Brain-Inspired Artificial Intelligence)

  • 김철호;이정훈;이성엽;우영춘;백옥기;원희선
    • 전자통신동향분석
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    • 제36권3호
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    • pp.106-118
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    • 2021
  • The field of brain science (or neuroscience in a broader sense) has inspired researchers in artificial intelligence (AI) for a long time. The outcomes of neuroscience such as Hebb's rule had profound effects on the early AI models, and the models have developed to become the current state-of-the-art artificial neural networks. However, the recent progress in AI led by deep learning architectures is mainly due to elaborate mathematical methods and the rapid growth of computing power rather than neuroscientific inspiration. Meanwhile, major limitations such as opacity, lack of common sense, narrowness, and brittleness have not been thoroughly resolved. To address those problems, many AI researchers turn their attention to neuroscience to get insights and inspirations again. Biologically plausible neural networks, spiking neural networks, and connectome-based networks exemplify such neuroscience-inspired approaches. In addition, the more recent field of brain network analysis is unveiling complex brain mechanisms by handling the brain as dynamic graph models. We argue that the progress toward the human-level AI, which is the goal of AI, can be accelerated by leveraging the novel findings of the human brain network.