• 제목/요약/키워드: updating system

검색결과 598건 처리시간 0.028초

Nonlinear identification of Bouc-Wen hysteretic parameters using improved experience-based learning algorithm

  • Luo, Weili;Zheng, Tongyi;Tong, Huawei;Zhou, Yun;Lu, Zhongrong
    • Structural Engineering and Mechanics
    • /
    • 제76권1호
    • /
    • pp.101-114
    • /
    • 2020
  • In this paper, an improved experience-based learning algorithm (EBL), termed as IEBL, is proposed to solve the nonlinear hysteretic parameter identification problem with Bouc-Wen model. A quasi-opposition-based learning mechanism and new updating equations are introduced to improve both the exploration and exploitation abilities of the algorithm. Numerical studies on a single-degree-of-freedom system without/with viscous damping are conducted to investigate the efficiency and robustness of the proposed algorithm. A laboratory test of seven lead-filled steel tube dampers is presented and their hysteretic parameters are also successfully identified with normalized mean square error values less than 2.97%. Both numerical and laboratory results confirm that, in comparison with EBL, CMFOA, SSA, and Jaya, the IEBL is superior in nonlinear hysteretic parameter identification in terms of convergence and accuracy even under measurement noise.

클러터 환경에 강인한 고속/소형의 접근 표적 탐지/추적 (Robust Detection and Tracking for a High-speed and Small Approaching Target in Clutter)

  • 김지은;노창균;이부환
    • 한국군사과학기술학회지
    • /
    • 제14권4호
    • /
    • pp.676-683
    • /
    • 2011
  • In this paper, we propose a robust method which can detect and track a high-speed small approaching target in a cluttered environment for Korean Active Protection System. The proposed method uses a temporal and spatial filter, tracking filter to detect and track a single target in consecutive order. And it is comprised of a candidate target detection step, a prior target selection step and a target tracking. Field tests on real infrared image sequences show that the proposed method could stably track a high speed and small target in complex background and target occlusion.

확률적 전력조류계산과 퍼지 전력조류계산과의 비교 연구 (Comparative study of Probabilistic Load Flow and Fuzzy Load Flow)

  • 정영수;심재홍;김진오
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1997년도 하계학술대회 논문집 D
    • /
    • pp.1100-1102
    • /
    • 1997
  • This paper presents a generalized multi-parameter distribution method for the convolution of linear combination of random variables to calculate system load flow in a conventional probabilistic approach and also presents a conceptual possibilistic approach using fuzzy set theory to manage uncertainties. The probability distribution function is transformed into an appropriate possibilistic representation under the compromise between the transformation consistency and the human updating experience. The IEEE 25-bus system is used to demonstrate the capability of the proposed algorithm.

  • PDF

On-line Parameter Estimator Based on Takagi-Sugeno Fuzzy Models

  • Park, Chang-Woo;Hyun, Chang-Ho;Park, Mignon
    • 한국지능시스템학회논문지
    • /
    • 제12권5호
    • /
    • pp.481-486
    • /
    • 2002
  • In this paper, a new on-line parameter estimation methodology for the general continuous time Takagi-Sugeno(T-5) fuzzy model whose parameters are poorly known or uncertain is presented. An estimator with an appropriate adaptive law for updating the parameters is designed and analyzed based on the Lyapunov theory. The adaptive law is designed so that the estimation model follows the plant parameterized model. By the proposed estimator, the parameters of the T-S fuzzy model can be estimated by observing the behavior of the system and it can be a basis for the indirect adaptive fuzzy control. Based on the derived design method, the parameter estimation for controllable canonical T-S fuzzy model is also Presented.

Java 서블릿을 이용한 웹 기반의 3-Tier 데이타베이스 시스템 설계 및 구현 (Design and Implementation of Internet Web-based 3-tier Database System by using Java Servlet)

  • 최재원
    • 한국통신학회논문지
    • /
    • 제28권1B호
    • /
    • pp.55-63
    • /
    • 2003
  • 기존의 PC 통신 서비스가 최근 인터넷에 기반을 둔 멀티미디어 웹 서비스로 빠르게 대체됨으로 인해 과거 많은 인력과 자금을 투자하여 개발한 유용한 데이터베이스와 PC 통신 환경 상의 많은 서비스가 시장되는 사용자로부터 도외시되어 사장되는 문제가 발생하고 있다 이에 본 연구에서는 과거 PC 통신 환경 상에서 제공되었던 텍스트 위주의 명령에 기초한 데이터베이스 서비스를 사용자의 정보 접근이 용이한 멀티미디어 웹에 기초한 데이터베이스 서비스로 전환하기 위한 시스템의 설계 및 구현방법에 관해 연구하였다

A Database Approach for Modeling and Querying XML Documents

  • Panseop Shin;Kim, Jeong-Eun;Lee, Jaeho;Haechull Lim
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2000년도 ITC-CSCC -2
    • /
    • pp.703-706
    • /
    • 2000
  • In recent years. XML applications are being developed in diverse area. Especially, development of XML document repository system associated with database is carrying out widely. The previous researches of XML repository system have several defects which are update and retrieval limitations for the XML document, design limitation for a formal retrieval algorithm and data redundancy. In order to solve the above problems. in this paper, we suggest relational database schemes for overcoming limitations of updating, retrieving, and rebuilding document. And suggest query translation strategy using two-phase translation that consists of pattern analyzing phase and SQL generating phase.

  • PDF

An Improved Hybrid Kalman Filter Design for Aircraft Engine based on a Velocity-Based LPV Framework

  • Liu, Xiaofeng
    • International Journal of Aeronautical and Space Sciences
    • /
    • 제18권3호
    • /
    • pp.535-544
    • /
    • 2017
  • In-flight aircraft engine performance estimation is one of the key techniques for advanced intelligent engine control and in-flight fault detection, isolation and accommodation. This paper detailed the current performance degradation estimation methods, and an improved hybrid Kalman filter via velocity-based LPV (VLPV) framework for these needs is proposed in this paper. Composed of a nonlinear on-board model (NOBM) and VLPV, the filter shows a hybrid architecture. The outputs of NOBM are used for the baseline of the VLPV Kalman filter, while the system performance degradation factors on-line estimated by the measured real system output deviations are fed back to the NOBM for its updating. In addition, the setting of the process and measurement noise covariance matrices' values are also discussed. By applying it to a commercial turbofan engine, simulation results show the efficiency.

철도기관사의 경험효과에 관한 연구 (A Study on the Experience Effect of Engine Drivers)

  • 김충수;안승호
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 1999년도 추계학술대회 논문집
    • /
    • pp.73-80
    • /
    • 1999
  • Belief revision involves integrating new information with the current belief. It is a ubiquitous human activity. A critical feature of belief revision lies in its sequential nature. Railroad system can be described as organic. Engine drivers take a great role in this system. Recently, Hogarth and Einhorn(1992) have Posited a belief-adjustment model for updating beliefs. Based on a sequential anchoring and adjustment strategy, the model is important fro decision makers. The sequential nature of information processing is affected by some task variables. This will be mainly explained in this paper. The purpose of this study is to examine the engine drivers' belief revision process and factors which influence on the belief revision process. The factors are the order and the experience. Thereby, this will contribute to the study of engine drivers' behavior. The result of this study is summarized as follows. The order effect due to the order of presentation of the evidence exist. The difference of belief revision is due to The experience level.

  • PDF

Embedded Object-Oriented Micromagnetic Frame (OOMMF) for More Flexible Micromagnetic Simulations

  • Kim, Hyungsuk;You, Chun-Yeol
    • Journal of Magnetics
    • /
    • 제21권4호
    • /
    • pp.491-495
    • /
    • 2016
  • We developed an embedded Object-Oriented Micromagnetic Frame (OOMMF) script schemes for more flexible simulations for complex and dynamic mircomagnetic behaviors. The OOMMF can be called from any kind of softwares by system calls, and we can interact with OOMMF by updating the input files for next step from the output files of the previous step of OOMMF. In our scheme, we set initial inputs for OOMMF simulation first, and run OOMMF for ${\Delta}t$ by system calls from any kind of control programs. After executing the OOMMF during ${\Delta}t$, we can obtain magnetization configuration file, and we adjust input parameters, and call OOMMF again for another ${\Delta}t$ running. We showed one example by using scripting embedded OOMMF scheme, tunneling magneto-resistance dependent switching time. We showed the simulation of tunneling magneto-resistance dependent switching process with non-uniform current density using the proposed framework as an example.

정보기술협정(ITA) 물품 품목분류 오류 사례 연구 (A Study on the Customs Classification Fallacy of certain ITA Goods)

  • 박민규
    • 무역학회지
    • /
    • 제44권2호
    • /
    • pp.189-202
    • /
    • 2019
  • The Harmonized System comprises about 5,000 commodity groups; each identified by a six digit code, arranged in a legal and logical structure and is supported by well-defined rules to achieve uniform classification. This study reviews the appropriateness of Korea Customs Service and Tax Tribunal's customs classification decisions concerning the interpretation and application of the Harmonized System for certain ITA goods. Korea Customs Service had classified arbitrary and had not applied in dubio pro reo principle. This paper finds that 57% of Korea Customs Service's classification decisions have erred. Korea government need to take measures to secure uniform interpretation of the HS and its periodic updating in light of developments in technology and changes in trade patterns. This paper suggest to amend customs law and regulation concerning classification committee.