• International Journal of Fuzzy Logic and Intelligent Systems
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• v.6 no.4
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• pp.271-276
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• 2006

To implement a generalization of value functions in Adaptive Search Element (ASE)-reinforcement learning, CMAC (Cerebellar Model Articulation Controller) is integrated into ASE controller. ASE-reinforcement learning scheme is briefly studied to discuss how CMAC is integrated into ASE controller. Neighbourhood Sequential Training for CMAC is utilized to establish the look-up table and to produce discrete control outputs. In computer simulation, an ASE controller and a couple of ASE-CMAC neural network are trained to balance the inverted pendulum on a cart. The number of trials until the controllers are established and the learning performance of the controllers are evaluated to find that generalization ability of the CMAC improves the speed of the ASE-reinforcement learning enough to realize the cartpole control system.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.9
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• pp.646-654
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• 1988

In this paper, a speed controller using a microcomputer is implemented and applied to a DC Servo Motor. Adaptive control is applied to a system for which a priori knowledge to its mathematical model is insufficient, on the basis of input and output data an apropriate controller is constructed through which the system input is synthesized. The pole-placement PID self tuning control algorithms as a control algorithm is used to compare the performance of the controller with that of the classical PID controller through computer simulations and experiments.

• Journal of Communications and Networks
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• v.9 no.2
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• pp.185-191
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• 2007

Alpha stable distribution is better for modeling impulsive noises than Gaussian distribution in signal processing. This class of process has no closed form of probability density function and finite second order moments. In general, Wiener filter theory is not meaningful in S$\alpha$SG environments because the expectations may be unbounded. We proposed a new adaptive recursive least p-norm Kalman filtering algorithm based on least p-norm of innovation process with infinite variances, and a new robust multiuser detection method based on least p-norm Kalman filtering. The simulation experiments show that the proposed new algorithm is more robust than the conventional Kalman filtering multiuser detection algorithm.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2396-2398
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• 2001

Active contour로 알려져 있는 snake는 반복적인 계산으로 이미지상에서 찾고자 하는 물체의 외곽선에 수렴하는 contour로 이미지 상의 물체의 외곽선으로부터 발생하는 외부 에너지(external energy)와 contour 자체로부터 기인하는 내부 에너지(internal energy)를 최소화하는 방향으로 움직인다. 그러나 물체의 윤곽선으로부터 발생하는 외부 에너지는 찾고자 하는 물체뿐만 아니라 주위의 다른 물체로부터도 발생하므로 만일 추적하고자 하는 물체의 주변에 다른 물체들이 존재한다면 snake은 올바르게 동작하지 않게 된다. 본 논문에서는 이러한 단점을 극복하기 위하여 물체의 색상정보를 이용하는 방식을 제안하였다. 물체의 색상 정보는 물체의 고유한 특성 중의 하나로 본 논문에서는 색상정보를 이용하여 원래의 이미지를 찾고자 하는 물체의 색상과 얼마나 유사한가를 나타내는 확률 이미지로 변환하였다. 이렇게 변환된 확률 이미지 상에서 snake 알고리즘을 적용함으로써 배경의 다른 물체로부터 발생하는 외부 에너지를 효과적으로 제거할 수 있다. 또한 본 논문에서는 물체가 이동함에 따라 변화하는 색상 정보를 지속적으로 갱신함으로써 물체의 추적이 효과적으로 이루어지도록 하였다.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2011-2013
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• 2001

In this paper the MMAE(Multiple Model Adaptive Estimation) algorithm using the MGEKF(Modified Gain Extended Kalman Filter) of which modes are set to be measurement biases is proposed to enhance the performance of target tracking with bearing only measurements. The state are composed of relative position, relative velocity and taregt acceleration. The mode probability is calculated from the bearing only measurements from the HMS(Hull-Mounted Sonar). The proposed algorithm is tested in a series of computer simulation runs.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.2
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• pp.293-300
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• 2011

A number of techniques have been developed for estimation of speed or position in motor drives. The accuracy of these techniques is affected by the variation of motor parameters such as the stator resistance, stator inductance or torque constant. This paper is proposed a neural network based estimator for torque and stator resistance and adaptive fuzzy learning contrroller(AFLC) for speed control in IPMSM Drives. AFLC is chaged fuzzy rule base by rule base modifier for robust control of IPMSM. The neural weights are initially chosen randomly and a model reference algorithm adjusts those weights to give the optimum estimations. The neural network estimator is able to track the varying parameters quite accurately at different speeds with consistent performance. The neural network parameter estimator has been applied to slot and flux linkage torque ripple minimization of the IPMSM. The validity of the proposed parameter estimator and AFLC is confirmed by comparing to conventional algorithm.

• Industrial Engineering and Management Systems
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• v.11 no.4
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• pp.339-345
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• 2012

This research aims to formulate a mathematical model and develop an algorithm for solving a location problem in emergency medical service vehicle parking. To find an optimal parking location which has the least risk score or risk priority number calculated from severity, occurrence, detection, and distance from parking location for emergency patients, data were collected from Pratoom sub-district Disaster Prevention and Mitigation Center from October 2010 to April 2011. The criteria of risk evaluation were modified from Automotive Industry Action Group's criteria. An adaptive simulated annealing algorithm with multiple cooling schedules called multi-agent simulated quenching (MASQ) is proposed for solving the problem in two schemes of algorithms including dual agent and triple agent quenching. The result showed that the solution obtained from both scheme of MASQ was better than the traditional solution. The best locations obtained from MASQ-dual agent quenching scheme was nodes #5 and #133. The risk score was reduced 61% from 6,022 to 2,371 points.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10b
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• pp.18-20
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• 2000

에이전트를 다른 소프트웨어와 구별 시켜주는 요인들은 여러 가지가 있지만 그 중에서도 가장 큰 특징은 에이전트의 자율성, 적응성, 그리고 지능을 들 수 있다. 이러한 것을 가능하게 만들기 위해서는 행동 선택을 유발하는 모티브의 생성이 자동적으로 이루어져야 한다. 이러한 행동 선택에 있어서 자동적인 모티브를 제공해 주는 것이 감정이다. 감정은 그것을 가지고 있는 자율 시스템이 그 동안 겪어온 외부 환경과 내부 상태에 대한 글로벌 상태를 함축하고 있다. 그러므로, 접근 가능한 정보와 자원이 제한되어 있는 자율 시스템이 다중의 목표, 환경에서의 모호성과 다른 에이전트와의 조정 등을 하는데 있어서 감정 모델은 유용한 해결책을 제시해 줄 수 있다. 본 논문에서는 에이전트가 환경과 적응하면서 변화하는 에이전트의 내부 상태의 변화와 외부 사건에 대한 에이전트의 인식과 평가를 계속 반영하여 에이전트가 시스템 환경을 경험하면서 가질 수 있는 에이전트만의 시스템에 대한 광범위한 시야를 갖도록 감정 모델을 구축하는 것을 목적으로 한다. 또한 이렇게 생성된 감정 델을 통해서 에이전트에 특정 사건이 발생하였을 때 에이전트가 감정 모델에 기초하여 적절히 행동에 반응할 수 있는 적응적 에이전트 모델을 제시한다.

• Journal of Communications and Networks
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• v.14 no.5
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• pp.510-517
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• 2012

This paper analyzes the performance of voice-over-Internet protocol (VoIP) services in terms of the system throughput, the packet delay, and the signaling overhead in a mobile WiMAX system with a hybrid automatic repeat request (HARQ) mechanism. Furthermore, a queueing analytical model is developed with due consideration of adaptive modulation and coding, the signaling overhead, and the retransmissions of erroneous packets. The arrival process is modeled as the sum of the arrival rate at the initial transmission queue and the retransmission queue, respectively. The service rate is calculated by taking the HARQ retransmissions into consideration. This paper also evaluates the performance of VoIP services in a mobile WiMAX system with and without persistent allocation; persistent allocation is a technique used to reduce the signaling overhead for connections with a periodic traffic pattern and a relatively fixed payload. As shown in the simulation results, the HARQ mechanism increases the system throughput as well as the signaling overhead and the packet delay.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.55 no.2
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• pp.103-109
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• 2006

In this paper, the detection scheme of the spatial coordinates based on stereo camera for a intelligent path planning of an automatic mobile robot is proposed. In the proposed system, face area of a moving person is detected from a left image among the stereo image pairs by using the YCbCr color model and its center coordinates are computed by using the centroid method and then using these data, the stereo camera embedded on the mobile robot can be controlled for tracking the moving target in real-time. Moreover, using the disparity mad obtained from the left and right images captured by the tracking-controlled stereo camera system and the perspective transformation between a 3-D scene. and an image plane, depth information can be detected. Finally, based-on the analysis of these calculated coordinates, a mobile robot system is derived as a intelligent path planning and a estimation.