• Journal of the Korean Statistical Society
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• v.16 no.2
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• pp.92-101
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• 1987

Our interest is to access in some way teh relative odds or probability that a multivariate observation Z belongs to one of k multivariate normal populations with unequal covariance matrices. We derived the empirical Bayes posterior odds ratio for the classification rule when population parameters are unknown. It is a generalization of the posterior odds ratio suggested by Gelsser (1964). The classification rule does not have complicated distribution theory which a large variety of techniques from the sampling viewpoint have. The proposed posterior odds ratio is compared to the Gelsser's posterior odds ratio through a Monte Carlo study. The results show that the empiricla Bayes posterior odds ratio, in general, performs better than the Gelsser's. Especially, for large dimension of Z and small training sample, the performance is prominent.

• Journal of the Korean Data and Information Science Society
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• v.6 no.2
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• pp.17-27
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• 1995

We propose a framework for representing and processing uncertain knowledge on the basis of constraint satisfaction. A system of equations and/or inequalities can be considered as a set of constraints that should be solved, and each constraint in the set is transformed into a corresponding logical formula which can be solved through a constraint solving program. Most of rule-based systems, for instance, use a simple probabilistic theory in order to maintain uncertain knowledge, therefore uncertain knowledge can be represented and processed in the constraint satisfaction program quite efficiently.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.693-698
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• 1991

This paper describes a fuzzy rule-based assembly algorithm for precision parts mating, The difficulties in devising reliable assembly strategies result from the complexity of the assembly process and the uncertainty such as imperfect knowledge of the parts being assembled as well as the limitations of the devices performing the assembly. To cope with above problems, we propose an assembly algorithm utilizing fuzzy set theory. The presented method allows us to represent the uncertainty by using fuzzy membership function and treat nonlinear sapping from measured force/torque to corrective motions using rules. Finally, the performance of this method is evaluated through a series of experiments. Experimental results show that the proposed method can be effectively used for chamferless and precision parts mating.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.2
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• pp.288-294
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• 2010

In recent years, wind energy has been the world's fastest growing source of energy. This paper describes the structural design and analysis of composite blade for 2 kW-level HAWT (horizontal axis wind turbine). The aerodynamic design and force, which are required to design and analyze a composite blade structurally, are calculated through BEMT(blade element momentum theory) implemented in public code PROPID. To obtain the equivalent material properties of filament wound composite blades, the rule-of-mixture is applied using the basic material properties of fiber and matrix, respectively. Lay-up sequence, ply thickness and ply angle are designed to satisfy the loading conditions. Structural analysis by using commercial software ABAQUS is performed to compute the displacement and strength ratio of filament wound composite blades.

• The Journal of the Acoustical Society of Korea
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• v.13 no.1
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• pp.93-98
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• 1994

This study aims to find the theoretical consideration of the basic simularity rule between scale model experiment and real building as a results ; 1. In the case of room acoustics, $f_m=n\cdot{f_r}\;T_m=T_r/n\; \alpha_m(f_m)=\alpha_r(f_r)$ 2. That of sound Insulation : $TL_m(f_m)=TL_r(f_r)$

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.8
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• pp.752-757
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• 2000

The recursive formulae, which can self-reproduce the state transition graphs, of one-dimensional cellular automata rule 15 with two states (0 and 1) and four different boundary conditions were founded by categorical access. The categorical access makes the evolution process for cellular automata be expressed easily since it enables the mapping of automata between different domains.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.22-27
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• 2004

Seop-Gye divided up the constitution's strength and weakness, and so he cured disease by the 'cold and heat'. 'deficiency and excessiveness' means on the basis of the YINㆍYANG of constitution. He classified constitution with pathogenesis grounding in body formal distinction, flesh hardness and softness, face color and form, skin color. Therefore he grasped the rule of constitution connected with physiological function and pathological distinction, applied the rule of constitution in the diagnosis and cure of the chronic & epidemic febrile disease.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.3
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• pp.504-509
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• 1987

In this paper a characteristics of image which can be segmented based on the thresholding technique using a histogram was investigated employing 3 parameters: the variance of pixel value, the average mean difference between target and background and the target size. The threshold value for the histogram segmentation was determined by applying the hypothesis testing theory. The performance of the selected threshold was evaluated by computing a probability of error. Since a priori probability can be easily obtained from the histogram, it was found that the Bayes decision rule which theoretically guarantees the minimum probability of error works better than the minimax criterion rule.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.4
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• pp.114-122
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• 2002

Up to now, many constitutive models for clay have been proposed and studied based on the elasto-plastic or elasto-viscoplastic theory and it has been recognized that the effect of time on the loading process is a salient feature. In the present study, cyclic behavior characteristics of clay was studied with a viscoelastic-viscoplastic constitutive model for clay based on the non-linear kinematic hardening rule. In order to examine the behavior of clay several cyclic untrained triaxial tests and also their numerical simulations were performed. As results of that, it was found that the proposed model can well describe cyclic behaviors of clay such as frequency dependent characteristics, and have the high feasibility of numerical simulation for dynamic analysis.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.2
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• pp.113-119
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• 2002

An FLNN-based neural network controller is applied to precise positioning of XY table with friction as the extension study of [11]. The neural network identifies the frictional farces of the table. Its weight adaptation rule, named the reinforcement adaptive learning rule, is derived from the Lyapunov stability theory. The experimental results with 2-DOF XY table verify the effectiveness of the proposed control scheme. It is also expected that the proposed control approach is applicable to a wide class of mechanical systems.