• 제목/요약/키워드: C.p. Networks

검색결과 104건 처리시간 0.022초

단순화된 패리티 공간기법을 이용한 원전 다중센서 신호검증 (Redundant Sensor Signal Validation of Nuclear Power Plants Using the Simplified Parity Space Method)

  • 오성헌;김대일;주운표;정윤형;류부형;임장현;김건중
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1993년도 정기총회 및 추계학술대회 논문집 학회본부
    • /
    • pp.317-319
    • /
    • 1993
  • The function estimation characteristics of neural networks can be used for sensor signal validation of a system. In case of applying the neural networks to signal validation, it is a important problem that the redundant sensor signals used as a input signal of neural networks should be validated. In this paper, we simplify the conventional parity space method in order to input the validated signal to the neural networks and also propose the sensor signal validation method, which estimates the reliable sensor output combining neural networks with the simplified parity space method. The acceptability of the proposed signal validation method is demonstrated by using the simulation data in safety injection accident of nuclear power plants.

  • PDF

An application of BP-Artificial Neural Networks for factory location selection;case study of a Korean factory

  • Hou, Liyao;Suh, Eui-Ho
    • 한국지능정보시스템학회:학술대회논문집
    • /
    • 한국지능정보시스템학회 2007년도 한국지능정보시스템학회
    • /
    • pp.351-356
    • /
    • 2007
  • Factory location selection is very important to the success of operation of the whole supply chain, but few effective solutions exist to deliver a good result, motivated by this, this paper tries to introduce a new factory location selection methodology by employing the artificial neural networks technology. First, we reviewed previous research related to factory location selection problems, and then developed a (neural network-based factory selection model) NNFSM which adopted back-propagation neural network theory, next, we developed computer program using C++ to demonstrate our proposed model. then we did case study by choosing a Korean steelmaking company P to show how our proposed model works,. Finnaly, we concluded by highlighting the key contributions of this paper and pointing out the limitations and future research directions of this paper. Compared to other traditional factory location selection methods, our proposed model is time-saving; more efficient.and can produce a much better result.

  • PDF

XML 기반의 철도물류정보 시스템 설계 및 구현 (The Design & Implementation of KROIS System Based on XML)

  • 안경림;박상필;임병찬;강은숙;조갑성
    • 한국IT서비스학회:학술대회논문집
    • /
    • 한국IT서비스학회 2002년도 창립기념 학술대회
    • /
    • pp.381-386
    • /
    • 2002
  • 급변하는 정보화 사회에서, 철도 물류 정보 분야는 업무 자동화에 대한 인식 부족, 데이터 실시간 처리 불가, 열악한 사용자 환경 등으로 인해 활성화되지 못하였다. 이러한 상황을 극복하기 위해 인터넷을 기반으로 하며 차세대 인터넷 표준으로 알려진 XML을 적용한 철도 물류 정보 연계 시스템을 구축하였다. 구축된 시스템은 기존의 철도 물류 정보 시스템의 기능과 성능을 개선하여 사용자에게 안정되고 편리한 서비스를 제공하기 위한 구조로 설계되었다. 또한 기존의 2-tier 형태의 WEB 구조를 3-tier 형태로 하여 보안이 강화된 구조로 하였으며, 새로운 인터넷 표준으로 각광받는 XML Schema와 XSL을 적용하여 앞서 나가는 철도 물류 정보 시스템이 되도록 하였다.

  • PDF

Investigation of smart multifunctional optical sensor platform and its application in optical sensor networks

  • Pang, C.;Yu, M.;Gupta, A.K.;Bryden, K.M.
    • Smart Structures and Systems
    • /
    • 제12권1호
    • /
    • pp.23-39
    • /
    • 2013
  • In this article, a smart multifunctional optical system-on-a-chip (SOC) sensor platform is presented and its application for fiber Bragg grating (FBG) sensor interrogation in optical sensor networks is investigated. The smart SOC sensor platform consists of a superluminescent diode as a broadband source, a tunable microelectromechanical system (MEMS) based Fabry-P$\acute{e}$rot filter, photodetectors, and an integrated microcontroller for data acquisition, processing, and communication. Integrated with a wireless sensor network (WSN) module in a compact package, a smart optical sensor node is developed. The smart multifunctional sensor platform has the capability of interrogating different types of optical fiber sensors, including Fabry-P$\acute{e}$rot sensors and Bragg grating sensors. As a case study, the smart optical sensor platform is demonstrated to interrogate multiplexed FBG strain sensors. A time domain signal processing method is used to obtain the Bragg wavelength shift of two FBG strain sensors through sweeping the MEMS tunable Fabry-P$\acute{e}$rot filter. A tuning range of 46 nm and a tuning speed of 10 Hz are achieved. The smart optical sensor platform will open doors to many applications that require high performance optical WSNs.

비 자율적 노드 위치 결정을 통한 DHT 네트워크 ID 매핑 공격 방지 (Preventing ID Mapping Attacks on DHT Networks through Non-Voluntary Node Locating)

  • 이철호;최경희;정기현;김종명;윤영태
    • 정보보호학회논문지
    • /
    • 제23권4호
    • /
    • pp.695-707
    • /
    • 2013
  • Kademlia와 같은 DHT(Distributed Hash Table) 네트워크는 참여노드들이 네트워크 토폴로지 상에서 자신의 위치를 자율적으로 결정하는 구조를 가지고 있으며 이를 악용한 ID 매핑 공격에 매우 취약하다. 그 결과 DHT 네트워크에서는 eclipse, DRDoS, 봇넷 은닉통신 등의 보안 문제가 지속적으로 발생되고 있다. 본 논문에서는 ID 매핑 공격을 방지하기 위한 비 자율적 노드 위치 결정 방법을 제안하고 NAT 호환성, 공격 저항성, 네트워크 다양성의 세 가지 측면의 분석을 통해 타 방어기법들과 비교를 수행하였다. 분석결과, 제안된 방법은 타 방어기법과 동등한 수준의 공격 저항성을 나타냄과 동시에 타 방어기법이 갖는 단점인 NAT 호환성과 네트워크 다양성 문제를 극복할 수 있음을 확인하였다.

최적화된 pRBF 뉴럴 네트워크에 이용한 삼상 부분방전 패턴분류에 관한 연구 (A Study on Three Phase Partial Discharge Pattern Classification with the Aid of Optimized Polynomial Radial Basis Function Neural Networks)

  • 오성권;김현기;김정태
    • 전기학회논문지
    • /
    • 제62권4호
    • /
    • pp.544-553
    • /
    • 2013
  • In this paper, we propose the pattern classifier of Radial Basis Function Neural Networks(RBFNNs) for diagnosis of 3-phase partial discharge. Conventional methods map the partial discharge/noise data on 3-PARD map, and decide whether the partial discharge occurs or not from 3-phase or neutral point. However, it is decided based on his own subjective knowledge of skilled experter. In order to solve these problems, the mapping of data as well as the classification of phases are considered by using the general 3-PARD map and PA method, and the identification of phases occurring partial discharge/noise discharge is done. In the sequel, the type of partial discharge occurring on arbitrary random phase is classified and identified by fuzzy clustering-based polynomial Radial Basis Function Neural Networks(RBFNN) classifier. And by identifying the learning rate, momentum coefficient, and fuzzification coefficient of FCM fuzzy clustering with the aid of PSO algorithm, the RBFNN classifier is optimized. The virtual simulated data and the experimental data acquired from practical field are used for performance estimation of 3-phase partial discharge pattern classifier.

Development of Thiourea-Formaldehyde Crosslinked Chitosan Membrane Networks for Separation of Cu (II) and Ni (II) Ions

  • Sudhavani, T.J.;Reddy, N. Sivagangi;Rao, K. Madhusudana;Rao, K.S.V. Krishna;Ramkumar, Jayshree;Reddy, A.V.R.
    • Bulletin of the Korean Chemical Society
    • /
    • 제34권5호
    • /
    • pp.1513-1520
    • /
    • 2013
  • Novel chitosan (CS) based membrane networks were developed by solution casting and followed by crosslinking with different crosslinkers such as glutaraldehyde, urea-formaldehyde, and thiourea-formaldehyde. The developed membrane networks were designated as CS-GA, CS-UF and CS-TF. Crosslinking reaction of CS membranes was confirmed by Fourier transform infrared spectroscopy. Membrane rigidity and compactness were studied by the differential scanning calorimetry. The surface morphology of CS membranes was characterized by scanning electron microscopy. The sorption behaviour with respect to contact time, initial pH and initial metal ion concentration were investigated. The maximum adsorption capacity of CS-GA, CS-UF and CS-TF sorbents was found to be 1.03, 1.2 and 1.18 mM/g for $Cu^{2+}$ and 1.48, 1.55 and 2.18 mM/g for $Ni^{2+}$ respectively. Swelling experiments have been performed on the membrane networks at $30^{\circ}C$. Desorption studies were performed in acid media and EDTA and it was found that the membranes are reusable for the metal ion removal for three cycles. The developed membranes could be successfully used for the separation of $Cu^{2+}$ and $Ni^{2+}$ metal ions from aqueous solutions.

Alumina/SiC 나노복합재료에서의 잔류 열응력 완화거동에 관한 연구 (Thermal Residual Stress Relaxation Behavior of Alumina/SiC Nanocomposites)

  • Choa, Y.H.;Niihara, K.;Ohji, T.;Singh, J.P.
    • 한국분말야금학회:학술대회논문집
    • /
    • 한국분말야금학회 2002년도 춘계학술강연 및 발표대회
    • /
    • pp.11-11
    • /
    • 2002
  • Plastic deformation was observed by TEM around the intragranular SiC particles in the $Al_2O_3$ matrix for $Al_2O_3/SiC$ nanocomposite system. The dislocations are generated at selected planes and there is a tendency for the dislocations to form a subgrain boundary structure with low-angel grain boundaries and networks. In this study, dislocation generated in the $Al_2O_3$ matrix during cooling down from sintering temperatures by the highly localized thermal stresses within and/or around SiC particles caused from the thermal expansion mismatch between $Al_2O_3$ matrix and SiC particle was observed. In monolithic $Al_2O_3$ and $Al_2O_3/SiC$ microcomposite system. These phenomena is closely related to the plastic relaxation of the elastic stress and strain energy associated with both thermal misfitting inclusions and creep behaviors. The plastic relaxation behavior was explained by combination of yield stress and internal stress.

  • PDF

다항식 방사형기저함수 신경회로망을 이용한 ASP 모델링 및 시뮬레이터 설계 (Design of Modeling & Simulator for ASP Realized with the Aid of Polynomiai Radial Basis Function Neural Networks)

  • 김현기;이승주;오성권
    • 전기학회논문지
    • /
    • 제62권4호
    • /
    • pp.554-561
    • /
    • 2013
  • In this paper, we introduce a modeling and a process simulator developed with the aid of pRBFNNs for activated sludge process in the sewage treatment system. Activated sludge process(ASP) of sewage treatment system facilities is a process that handles biological treatment reaction and is a very complex system with non-linear characteristics. In this paper, we carry out modeling by using essential ASP factors such as water effluent quality, the manipulated value of various pumps, and water inflow quality, and so on. Intelligent algorithms used for constructing process simulator are developed by considering multi-output polynomial radial basis function Neural Networks(pRBFNNs) as well as Fuzzy C-Means clustering and Particle Swarm Optimization. Here, the apexes of the antecedent gaussian functions of fuzzy rules are decided by C-means clustering algorithm and the apexes of the consequent part of fuzzy rules are learned by using back-propagation based on gradient decent method. Also, the parameters related to the fuzzy model are optimized by means of particle swarm optimization. The coefficients of the consequent polynomial of fuzzy rules and performance index are considered by the Least Square Estimation and Mean Squared Error. The descriptions of developed process simulator architecture and ensuing operation method are handled.

다중텅그스텐산 아민염의 분자량 측정 (Cryoscopy of Amine-Polytungstates)

  • 변종홍;연손수
    • 대한화학회지
    • /
    • 제18권2호
    • /
    • pp.126-131
    • /
    • 1974
  • 비수용성 긴고리 지방족 아민인$(n-C_8H_{17})_3N$$(n-C_8H_{17})_3NCH_3Cl$을 사용하여 산도가 틀린 텅그스텐산수용액(pH=2, 4, 6)으로 부터 용매추출법에 의하여 유기용매에 녹는 다중텅그스텐산아민염을 제조하는데 성공하였다. 제조된 텅그스텐산 아민염의 분자량을 벤젠용매에서 더미스트를 이용한 감도 1/$4000^{\circ}C$의 훼트스톤 브리지를 사용하여 측정할 수 있었다. 분자량 측정결과와 화학분석 및 적외선 스펙트럼으로 부터 pH=2, 4에서 생긴 아민염은 메타텅그스텐산염, pH=6에서 생긴 아민염은 파라텅그스텐산염이 아니고 미지의 새로운 다중텅고스텐산염임을 알 수 있었다.

  • PDF