• Steel and Composite Structures
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• 제3권4호
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• pp.231-242
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• 2003

This paper deals with the formulation and development of fracture criteria for high-strength structural members containing surface damage in the form of notches (i.e., blunt defects). The important role of the yield strength of the material and its strain hardening capacity (evaluated by means of the constitutive law or stress-strain curve) is analysed in depth by considering the fracture performance of notched samples taken from high-strength steels with different levels of cold drawing (the most heavily drawn steel being commercial prestressing steel used in prestressed concrete). The final aim of the paper is to establish fracture-based design criteria for structural members made of steels with distinct yield strength and containing very different kinds of notch-shape surface damage.

• Communications for Statistical Applications and Methods
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• 제22권6호
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• pp.531-542
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• 2015

In this survey, we use the normal linear model to demonstrate the use of the linear Bayes method. The superiorities of linear Bayes estimator (LBE) over the classical UMVUE and MLE are established in terms of the mean squared error matrix (MSEM) criterion. Compared with the usual Bayes estimator (obtained by the MCMC method) the proposed LBE is simple and easy to use with numerical results presented to illustrate its performance. We also examine the applications of linear Bayes method to some other distributions including two-parameter exponential family, uniform distribution and inverse Gaussian distribution, and finally make some remarks.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 제14회 신호처리 합동 학술대회 논문집
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• pp.619-622
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• 2001

In this paper, an efficient approach to classification of transient and harmonic disturbances in power systems is proposed. First, the Stop-and-Go CA CFAR Detector is utilized to detect a disturbance from the power signals which are mixed with other disturbances and noise. Then, (i) Wigner Distribution, SVD(Singular Value Decomposition) and Fisher´s Criterion (ii) DWT and Fisher´s Criterion, are applied to extract an efficient feature vector. For the classification procedure, a combined neural network classifier is proposed to classify each corresponding disturbance class. Finally, the 10 class data simulated by Matlab power system blockset are used to demonstrate the performance of the proposed classification system.

• 품질경영학회지
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• 제28권1호
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• pp.119-131
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• 2000

This paper suggests a new diagnostic measure for detecting influential observations in linear discriminant analysis (LDA). It is developed from a Bayesian point of view using a default Bayes factor obtained from the imaginary training sample methodology. The Bayes factor is taken as a criterion for testing homogeneity of covariance matrices in LDA model. It is noted that the effect of an observation over the criterion is fully explained by the diagnostic measure. We suggest a graphical method that can be taken as a tool for interpreting the diagnostic measure and detecting influential observations. Performance of the measure is examined through an illustrative example.

• 한국경영과학회지
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• 제6권2호
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• pp.13-19
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• 1981

This paper developed 3 flow-shop sequencing heuristic methods: modified RA method, modified RACS method and modified RAES method. These methods modified RA method, RACS method and RAES method developed by D. G. Dannenbring. These methods can easily determine desirable sequence of orders and can improve nx3 flow-shop's productivity and efficiency. The maximum flow-time criterion is selected as the evaluation criterion of flow-shop's efficiency, We evaluated these 6 heuristic methods’ performance. By the evaluation of the result, we can see that the modified methods produce a shorter maximum flow-time than the original methods.

• 한국정보통신학회논문지
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• 제14권7호
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• pp.1544-1550
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• 2010

비선형 동적 시스템을 모델링하기 위해 GMDH(Group Method of Data Handling)를 적용한 많은 연구들이 수행되어 왔다. 그러나 모델링의 정확성을 위해서는 계산량이 크게 증가한다. 그러므로 본 논문에서는 입력 데이터를 취사선택하는 기준을 점감적으로 조정함으로써 적어도 정확성을 유지하면서 전형적인 GMDH의 단점인 과도한 계산을 피할 수 있는 방법을 제안한다. 컴퓨터 시뮬레이션 결과, GMDH 알고리듬의 계산량을 성공적으로 줄일 수 있었고 에러율도 소폭 줄일 수 있었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 춘계학술대회 논문집
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• pp.101-106
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• 1997

This paper proposes a stable adaptive neural network control(NNC) for fixable joint manipulators. For designing the stable adaptive NNC, the flexible system dynamics is separated into fast and slow subdynamics according to singular perturbation concept. For the slow subdynamics, an adaptive NNC is designed to warrant the system stability and NN learning by lyapunov stability criterion. And to stabilize the fast dynamics, derivative control loop is installed. Through numerical simulation, the performance of the proposed NNC was compared to that of an adaptive controller designed based on the knowledge of the system dynamics. The proposed NNC shows much improvement over the conventional adaptive controller.

• 한국군사과학기술학회지
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• 제13권2호
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• pp.188-195
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• 2010

Unlike using a single sonar platform, using two different sonar platforms can lead to a considerable increase of acoustic aperture in Passive Ranging Sonar(PRS). Values measured from two sonar platforms shall be consistent in order to allow us to rely on such improved aperture. However, obtaining consistent values from a towed array and a frank array is not always simple due to the heading error occurring at towed array. The objective of this paper is to verify a new criterion analyzing the consistency in the measured values of towed array and frank array through computer simulations.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.573-578
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• 1991

A stability analysis technique has been proposed for linear SISO system associated with fuzzy logic controller. An analysis technique using the concept of well-known sector bound nonlinearity and its graphical interpretation, i.e., the circle criterion, is presented. Thus the use of classical Nyquist locus and the BODE diagram is brought into the picture. The aim of this present note is to represent a graphical approach based on sector bound nonlinearity and circle criterion for assessing the performance(degree of stability) of the linear SISO system associated with fuzzy logic controller. The degree of stability of the system is defined in terms of its gain and phase margins as defined in Section 3.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
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• pp.428-431
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• 1995

In this paper we propose an on-line tuning method by using genetic algorithm for robust minimax I-PD controller based on new criterion. The new criterion is the Integral of Squared Error (ISE) with a penalty of the derivative of manipulated variable. The work focuses on robust tuning of I-PD controller's parameters in the presence of plant parameter uncertainty. The result of several simulation studies are provided to illustrate the performance of this robust tunig method.