• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2006년도 추계학술대회 학술발표 논문집 제16권 제2호
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• pp.193-196
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• 2006

프로펠러 회전면에서의 반류분포는 주로 모형시험에 의해서 규명되어 왔다. 이렇게 축적된 데이터베이스를 통해 선박의 기하학적 형상정보와 반류분포 사이의 입출력관계를 모델링할 수 있다. 면 선박 초기설계시 유사선종의 설계에 도움이 된다. 본 연구에서는 이들 입출력 사이의 관계를 뉴로퍼지시스템으로 모델링하고 학습한 후 새로운 입력에 대한 출력값의 검토를 통해 그 유용성을 확인한다.

• 한국ITS학회 논문지
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• 제8권4호
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• pp.28-32
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• 2009

본 논문은 DFT기반의 단일마이크 음성향상 방식에 적용된 두 종류의 generalized-Gamma 분포기반의 음성추정 알고리즘을 비교한다. 음성향상 방식으로서는 최소잡음성분에 의한 회귀적인 평균스펙트럼 값으로부터 유도되는 잡음 추정을 각각 $\kappa$=1인 경우와 $\kappa$=2인 경우의 Gamma 분포를 이용한 음성추정 기법에 결합하여 음질을 향상시켰다. 각 방식에 의해 향상된 음성신호를 자동차 환경에서의 음성인식에 적용하여 그 성능을 비교하였다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제8권2호
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• pp.116-120
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• 2008

Clustering is a method for unsupervised learning. General clustering tools have been depended on statistical methods and machine learning algorithms. One of the popular clustering algorithms based on machine learning is the self organizing map(SOM). SOM is a neural networks model for clustering. SOM and extended SOM have been used in diverse classification and clustering fields such as data mining. But, SOM has had a problem determining optimal number of clusters. In this paper, we propose an improvement of SOM using gap statistic and probability distribution. The gap statistic was introduced to estimate the number of clusters in a dataset. We use gap statistic for settling the problem of SOM. Also, in our research, weights of feature nodes are updated by probability distribution. After complete updating according to prior and posterior distributions, the weights of SOM have probability distributions for optima clustering. To verify improved performance of our work, we make experiments compared with other learning algorithms using simulation data sets.

• 전기학회논문지
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• 제58권9호
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• pp.1651-1657
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• 2009

In this paper, restoration solution algorithm to improve reliability better than restoration system of DAS(Distribution Automation System) is proposed in IDMS(Intelligent Distribution Management System). A strategy of IDMS restoration system to improve reliability and efficiency is proposed by analysis restoration system in DAS. Restoration sequence algorithm, distributed restoration solution algorithm considering a characteristic and a suitable restoration solution algorithm in IDMS are proposed. In the case study, algorithms have testified with example distribution network by C language

• Journal of Electrical Engineering and Technology
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• 제3권2호
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• pp.192-198
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• 2008

This paper proposes a FRTU-based intelligent fault distance determination strategy in which each FRTU is able to avoid multiple estimations and reduce the level of estimation error by utilizing heuristic rules driven by voltage and current information collected by 1:1 communication with other FRTUs from the same zone in a ubiquitous-based distribution system. In the proposed method, each FRTU, at first, determines a fault zone and a fault path on the faulted zone based on the proposed heuristic rules which use its current data and the voltage data of its neighboring FRTUs as input data. Next, it determines the fault distance from its position based on the fault current estimated from the current data of the neighboring FRTUs. Finally, in order to prove the effectiveness of the proposed method, the diverse fault cases are simulated in several positions of the typical distribution system using the EMTP.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.1043-1050
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• 2014

Obsolescent control systems for power systems are evolving into intelligent systems and connecting with smart devices to give intelligence to the power systems. As networks of the control system are growing, vulnerability is also increasing. The communication network of distribution areas in the power system connects closely to vulnerable environments. Many cyber-attacks have been founded in the power system, and they could be more critical as the power system becomes more intelligent. From these environment, new communication network architecture and mitigation method against cyber-attacks are needed. Availability and Fault Tree analysis used to show that the proposed system enhances performance of current control systems.

• 전기학회논문지
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• 제56권3호
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• pp.443-450
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• 2007

We overview the current distribution automation system in Korea and point out the limitations of the distribution services which can be provided by the current system. In this paper we propose a new distribution system architecture which is based on the peer-to-peer communication model. In this decentralized architecture the intelligent FRTUS can initiate data transmission without any interruption of a central server, and can exchange data with other FRTUS as peers. In order to support the peer-based distribution system, we specify the requirements for new communication network and suggest a way of improving the current distribution network where we adapt an intelligent module for protection and restoration, called MASX, and utilize the open communication network protocols. We also show how the new architecture can enhance major distribution services such as protection, automatic restoration, and equipment management.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1059-1062
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• 1998

This paper which can simulate FRIENDS(Flexible Reliable Intelligent Electrical eNergy Delivery System) model of distribution electrical system presents a new algorithm. In the operation of FRIENDS model, dispersed energy storage(DES) systems have an important role. We can use the active and reactive power of DES to control customer's voltage. In this, the former means load levelling operation and the later means voltage control operation of DES. We focus our research on load levelling operation of DES. We develope an algorithm to get an optimal capacity and operation schedule of DES and then apply it to the FRIENDS model. The results show the effectiveness of the proposed method.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.714-719
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• 2005

In this paper, the informative space is proposed to implant ubiquitous functions into physical spaces. We merge physical and virtual spaces through the space structurization using an RFID system, and solve the space localization and mapping problem for a robot to navigate through the distribution and synthesis of information and knowledge. To distribute knowledge flexibly and reliably to changing environment and also to develop a system which allows a robot to invoke and merge the distributed knowledge more freely, we employ a novel approach of knowledge management based on Web services. The proposed method is verified by building a physical space with two kinds of RFID tags and a virtual space with knowledge database based on Web services.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(3)
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• pp.37-40
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• 2001

There are over a billion web sites on the Internet and the number of web sites is still growing. This paper describes an information system. We have designed Trigger Agent System based on RMI (Remote Method invocation) and distribution object system. In this paper, we introduce Trigger agent system which is one of Intelligent agent system.