• 제목/요약/키워드: Reliable Method

검색결과 5,238건 처리시간 0.033초

An efficient method for reliable optimum design of trusses

  • Dizangian, Babak;Ghasemi, Mohammad Reza
    • Steel and Composite Structures
    • /
    • 제21권5호
    • /
    • pp.1069-1084
    • /
    • 2016
  • This paper introduces a new and effective design amplification factor-based approach for reliable optimum design of trusses. This paper may be categorized as in the family of decoupled methods that aiming for a reliable optimum design based on a Design Amplification Factor (DAF). To reduce the computational expenses of reliability analysis, an improved version of Response Surface Method (RSM) was used. Having applied this approach to two planar and one spatial truss problems, it exhibited a satisfactory performance.

구동기 고장을 가지는 특이시스템의 신뢰 $H_\infty$ 제어 (Reliable $H_\infty$ control for descriptor systems with actuator failures)

  • 김종해
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 A
    • /
    • pp.135-138
    • /
    • 2003
  • In this paper, we provide a reliable few controller design method for descriptor systems satisfying asymptotic stability with $H_\infty$ norm bound and all actuator failures occurred within the pre-specified subset. The proper condition for the existence of a reliable $H_\infty$ controller and the controller design method are proposed by linear matrix inequality(LMI), Schur complements, and singular value decomposition. All solutions can be obtained simultaneously because the presented sufficient condition can be expressed as an LMI form.

  • PDF

ISM에 의한 마찰용접재(SUH3-SUH35)의 고온크리프 수명예측에 관한 연구 (High Temperature Creep Life Prediction of Friction Welded Joints by Initial Strain Method and the AE Evaluation)

  • 오세규;이원석
    • 한국해양공학회지
    • /
    • 제11권4호
    • /
    • pp.40-48
    • /
    • 1997
  • There are many research results as individual uni-axial tension creep test of heat-resisting materials. However, there are very few about the study on the high temperature creep test for the Initial Strain Method, and especially any study on it about the friction welded joints of SUH3 to SUH35. One of the important concerns is a reliable method of evaluating static creep properties. No reliable method seems available at present to evaluate or predict static creep properties. So, the reliable method to evaluate and predict them by the ISM and AE techniques was made.

  • PDF

고장 특이시스템의 신뢰 $H_\infty$ 제어기 설계 알고리듬 개발 (Development of reliable $H_\infty$ controller design algorithm for singular systems with failures)

  • 김종해
    • 전자공학회논문지SC
    • /
    • 제41권4호
    • /
    • pp.29-37
    • /
    • 2004
  • 본 논문에서는 구동기 고장을 가지는 시간지연 특이시스템의 신뢰 H/sub ∞/ 상태궤환 제어기 설계방법을 제안한다. 미리 설정한 영역내에서의 구동기 고장이 발생함에도 불구하고 특이시스템의 점근적 안정성(asymptotic stability)과 H/sub ∞/ 성능지수를 만족하는 신뢰 H/sub ∞/ 제어기가 존재할 조건과 제어기 설계 기법을 선형행렬부등식, 특이값 분해(singular value decomposition), 슈어 여수정리(Schur complements), 변수 치환 등에 의하여 제시한다. 제안한 충분조건은 구하려는 모든 변수의 견지에서 하나의 선형행렬부등식으로 표현되기 때문에 모든 해를 동시에 구할 수 있다는 장점이 있다. 또한, 제안한 알고리듬을 이용하면 변수불확실성과 시간지연을 가지는 특이시스템에 대한 강인 신뢰(robust reliable) H/sub ∞/ 제어기 설계문제에도 쉽게 확장됨을 보인다. 마지막으로, 제안한 알고리듬의 타당성을 수치예제를 통하여 확인한다.

영상 디블러링에서의 임의 잡음 제거를 위한 로지스틱 회귀 (A Logistic Regression for Random Noise Removal in Image Deblurring)

  • 이남용
    • 한국멀티미디어학회논문지
    • /
    • 제20권10호
    • /
    • pp.1671-1677
    • /
    • 2017
  • In this paper, we propose a machine learning method for random noise removal in image deblurring. The proposed method uses a logistic regression to select reliable data to use them, and, at the same time, to exclude data, which seem to be corrupted by random noise, in the deblurring process. The proposed method uses commonly available images as training data. Simulation results show an improved performance of the proposed method, as compared with the median filtering based reliable data selection method.

Kyphotic Angle Measurement Accuracy for Vertebral Osteoporotic Compression Fracture; Reliable Method for Kyphotic Angle Measurement

  • Hong, Jae-Taek;Lee, Sang-Won;Son, Byung-Chul;Sung, Jae-Hoon;Park, Choon-Keun;Kim, Moon-Chan
    • Journal of Korean Neurosurgical Society
    • /
    • 제39권4호
    • /
    • pp.256-259
    • /
    • 2006
  • Objective : Having a reliable and reproducible measurement technique to measure the sagittal contour in vertebral fractures is paramount to clinical decision making. This study is designed to determine the most reliable measurement technique in osteoporotic vertebral compression fracture. Methods : Fifteen lateral radiographs of thoracic and lumbar fractures were selected and measured on two separate occasions by three spine surgeons using six different measurement techniques [Centroid, Harrison Posterior Tangent Methods and 4 different types of modified Cobb method]. The radiograph quality was assessed and the center beam location was determined. Statistical analysis including ANOVA for repeated measures was carried out using the SAS software [v 8.0]. Results : The inter and intraobserver variance of the Cobb method 4 and Harrison posterior tangent method were significantly lower than the other four methods. The intraobserver correlation coefficients were the most consistent using the Cobb method 4 [0.982]. which was followed by the Harrison posterior tangent [0.953] and Cobb methods 1 [0.874]. The intraobserver agreement [% of repeated measures within 5 degrees of the original measurement] ranged from 42% to 98% for each technique for all three observers, with the Cobb method 4 showing the best agreement [97.8%] followed by the Harrison posterior tangent method [937%]. Conclusion : The Cobb method-4 and Harrison posterior tangent methods, when applied to measuring the kyphosis, are reliable and have a similar small error range. The Cobb method 4 shows the best overall reliability. However, the centroid method and Cobb method using a fractured endplate do not produce an accurate result due to inter and intraobserver differences in determining the baseline.

신뢰성 있는 H 제어 : 선형 행렬 부등식 방법 (Reliable H Control : A Linlear Matrix Inequality Approach)

  • 이종민;김병국;김성우
    • 제어로봇시스템학회논문지
    • /
    • 제10권3호
    • /
    • pp.216-224
    • /
    • 2004
  • In this paper we address reliable output feedback control problem for a class of linear systems with actuator/sensor failures. An output feedback control method is proposed which stabilizes the plant and guarantees $H_\inftyt$-norm constraint against all admissible actuator/sensor failures. The controller can be obtainer by solving some LMls that cover all failure cases. Effectiveness of this controller is validated via a numerical example. This paper addresses reliable output feedback control problem for a class of linear systems with actuator/sensor failures. An output feedback control method is proposed which stabilizes the plant and guarantees $H_\inftyt$-norm constraint against all admissible actuator/sensor failures. The controller can be obtained by solving some LMls that cover all failure cases. Effectiveness of this controller is validated via numerical example.

제곱합 접근법에 의한 비선형시스템의 신뢰성제어 (A Reliable Control of Nonlinear Systems via a Sum of Squares Approach)

  • 류석환
    • 한국신뢰성학회지:신뢰성응용연구
    • /
    • 제12권2호
    • /
    • pp.121-129
    • /
    • 2012
  • This paper deals with a design of reliable state feedback controllers for continuous time polynomial systems with actuator failures. The goal is to find an asymptotically stabilizing controller such that the closed loop system achieves the prescribed decay rate in the actuator failure cases. Based on a sum of squares (SOS) approach, a design method for reliable nonlinear controller is presented. In order to demonstrate our design method, a numerical example is shown.

유전자 알고리즘을 이용한 신뢰 통신망 최적화 (Optimizing Reliable Network using Genetic Algorithm)

  • 이학종;강주락;권기호
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1999년도 추계종합학술대회 논문집
    • /
    • pp.452-455
    • /
    • 1999
  • Genetic algorithm is well known as the efficient algorithm which can solve a difficult problem. Network design considering reliability is NP-hard problem with cost, distance, and volume. Therefore genetic algorithm is considered as a good method for this problem. This paper suggests the reliable network which can be constructed with minimum cost using genetic algorithm and the rank method based on reliability for improving the performance. This method shows more excellent than existing method and confirms the result through simulation.

  • PDF

Metaheuristics for reliable server assignment problems

  • Jang, Kil-Woong;Kim, Jae-Hwan
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제38권10호
    • /
    • pp.1340-1346
    • /
    • 2014
  • Previous studies of reliable server assignment considered only to assign the same cost of server, that is, homogeneous servers. In this paper, we generally deal with reliable server assignment with different server costs, i.e., heterogeneous servers. We formulate this problem as a nonlinear integer programming mathematically. Our problem is defined as determining a deployment of heterogeneous servers to maximize a measure of service availability. We propose two metaheuristic algorithms (tabu search and particle swarm optimization) for solving the problem of reliable server assignment. From the computational results, we notice that our tabu search outstandingly outperforms particle swarm optimization for all test problems. In terms of solution quality and computing time, the proposed method is recommended as a promising metaheuristic for a kind of reliability optimization problems including reliable sever assignment and e-Navigation system.