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Dive into the research topics where Hyun-Chang Yang is active.

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Featured researches published by Hyun-Chang Yang.


society of instrument and control engineers of japan | 2006

Genetic Algorithm Based Feature Selection Method Development for Pattern Recognition

Ho-Duck Kim; Chang-Hyun Park; Hyun-Chang Yang; Kwee-Bo Sim

An important problem of pattern recognition is to extract or select feature set, which is included in the pre-processing stage. In order to extract feature set, principal component analysis has been usually used and SFS (sequential forward selection) and SBS (sequential backward selection) have been used as a feature selection method. This paper applies genetic algorithm which is a popular method for nonlinear optimization problem to the feature selection problem. So, we call it genetic algorithm feature selection (GAFS) and this algorithm is compared to other methods in the performance aspect


The International Journal of Fuzzy Logic and Intelligent Systems | 2008

Object tracking algorithm of Swarm Robot System for using Polygon based Q-learning and parallel SVM

Snag-Wook Seo; Hyun-Chang Yang; Kwee-Bo Sim

This paper presents the polygon-based Q-leaning and Parallel SVM algorithm for object search with multiple robots. We organized an experimental environment with one hundred mobile robots, two hundred obstacles, and ten objects. Then we sent the robots to a hallway, where some obstacles were lying about, to search for a hidden object. In experiment, we used four different control methods: a random search, a fusion model with Distance-based action making (DBAM) and Area-based action making (ABAM) process to determine the next action of the robots, and hexagon-based Q-learning, and dodecagon-based Q-learning and parallel SVM algorithm to enhance the fusion model with Distance-based action making (DBAM) and Area-based action making (ABAM) process. In this paper, the result show that dodecagon-based Q-learning and parallel SVM algorithm is better than the other algorithm to tracking for object.


international conference on control, automation and systems | 2007

Behavior learning and evolution of swarm robot system using SVM

Sang-Wook Seo; Kwang-Eun Ko; Hyun-Chang Yang; Kwee-Bo Sim

In swarm robot systems, each robot must behaves by itself according to the its states and environments, and if necessary, must cooperates with other robots in order to carry out a given task. Therefore it is essential that each robot has both learning and evolution ability to adapt the dynamic environments. In this paper, reinforcement learning method with SVM based on structural risk minimization and distributed genetic algorithms is proposed for behavior learning and evolution of collective autonomous mobile robots. By distributed genetic algorithm exchanging the chromosome acquired under different environments by communication each robot can improve its behavior ability. Specially, in order to improve the performance of evolution, selective crossover using the characteristic of reinforcement learning that basis of SVM is adopted in this paper.


Journal of Korean Institute of Intelligent Systems | 2008

Behavior Learning and Evolution of Swarm Robot System using Support Vector Machine

Sang-Wook Seo; Hyun-Chang Yang; Kwee-Bo Sim

In swarm robot systems, each robot must act by itself according to the its states and environments, and if necessary, must cooperate with other robots in order to carry out a given task. Therefore it is essential that each robot has both learning and evolution ability to adapt the dynamic environments. In this paper, reinforcement learning method with SVM based on structural risk minimization and distributed genetic algorithms is proposed for behavior learning and evolution of collective autonomous mobile robots. By distributed genetic algorithm exchanging the chromosome acquired under different environments by communication each robot can improve its behavior ability. Specially, in order to improve the performance of evolution, selective crossover using the characteristic of reinforcement learning that basis of SVM is adopted in this paper.


Journal of Korean Institute of Intelligent Systems | 2006

Emotion Recognition Method of Facial Image using PCA

Ho-Duck Kim; Hyun-Chang Yang; Chang-Hyun Park; Kwee-Bo Sim

A research about facial image recognition is studied in the most of images in a full race. A representative part, effecting a facial image recognition, is eyes and a mouth. So, facial image recognition researchers have studied under the central eyes, eyebrows, and mouths on the facial images. But most people in front of a camera in everyday life are difficult to recognize a fast change of pupils. And people wear glasses. So, in this paper, we try using Principal Component Analysis(PCA) for facial image recognition in blindfold case.


The International Journal of Fuzzy Logic and Intelligent Systems | 2009

Behavior Learning of Swarm Robot System using Bluetooth Network

Sang-Wook Seo; Hyun-Chang Yang; Kwee-Bo Sim

With the development of techniques, robots are getting smaller, and the number of robots needed for application is greater and greater. How to coordinate large number of autonomous robots through local interactions has becoming an important research issue in robot community. Swarm Robot Systems (SRS) is a system that independent autonomous robots in the restricted environments infer their status from preassigned conditions and operate their jobs through the cooperation with each other. In the SRS, a robot contains sensor pan to percept the situation around them, communication part to exchange information, and actuator pan to do a work. Especially, in order to cooperate with other robots, communicating with other robots is one of the essential elements. Because Bluetooth has many advantages such as low power consumption, small size module package, and various standard protocols, it is rated as one of the efficient communicating technologies which can apply to small-sized robot system. In this paper, we will develop Bluetooth communicating system for autonomous robots. And we will discuss how to construct and what kind of procedure to develop the communicating system for group behavior of the SRS under intelligent space.


Journal of Korean Institute of Intelligent Systems | 2007

Emotion Recognition Method using Physiological Signals and Gestures

Ho-Duck Kim; Hyun-Chang Yang; Kwee-Bo Sim

Researchers in the field of psychology used Electroencephalographic (EEG) to record activities of human brain lot many years. As technology develope, neural basis of functional areas of emotion processing is revealed gradually. So we measure fundamental areas of human brain that controls emotion of human by using EEG. Hands gestures such as shaking and head gesture such as nodding are often used as human body languages for communication with each other, and their recognition is important that it is a useful communication medium between human and computers. Research methods about gesture recognition are used of computer vision. Many researchers study emotion recognition method which uses one of physiological signals and gestures in the existing research. In this paper, we use together physiological signals and gestures for emotion recognition of human. And we select the driver emotion as a specific target. The experimental result shows that using of both physiological signals and gestures gets high recognition rates better than using physiological signals or gestures. Both physiological signals and gestures use Interactive Feature Selection(IFS) for the feature selection whose method is based on a reinforcement learning.


Journal of Institute of Control, Robotics and Systems | 2007

Object Tracking Algorithm for Intelligent Robot using Sound Source Tracking Sensor Network

In-Hun Jang; Kyoung-Jin Park; Hyun-Chang Yang; Jong-Chang Lee; Kwee-Bo Sim

Most of life thing including human being have tendency of reaction with inherently their own pattern against environmental change caused by such as light, sound, smell etc. Especially, a sense of direction often works as a very important factor in such reaction. Actually, human or animal lift that can react instantly to a stimulus determine their action with a sense of direction to a stimulant. In this paper, we try to propose how to give a sense of direction to a robot using sound being representative stimulant, and tracking sensors being able to detect the direction of such sound source. We also try to propose how to determine the relative directions among devices or robots using the digital compass and the RSSI on wireless network.


Journal of Institute of Control, Robotics and Systems | 2007

Emotion Recognition and Expression Method using Bi-Modal Sensor Fusion Algorithm

Jong-Tae Joo; In-Hun Jang; Hyun-Chang Yang; Kwee-Bo Sim

In this paper, we proposed the Bi-Modal Sensor Fusion Algorithm which is the emotional recognition method that be able to classify 4 emotions (Happy, Sad, Angry, Surprise) by using facial image and speech signal together. We extract the feature vectors from speech signal using acoustic feature without language feature and classify emotional pattern using Neural-Network. We also make the feature selection of mouth, eyes and eyebrows from facial image. and extracted feature vectors that apply to Principal Component Analysis(PCA) remakes low dimension feature vector. So we proposed method to fused into result value of emotion recognition by using facial image and speech.


Journal of Korean Institute of Intelligent Systems | 2009

Behavior Learning and Evolution of Swarm Robot System using Q-learning and Cascade SVM

Sang-Wook Seo; Hyun-Chang Yang; Kwee-Bo Sim

In swarm robot systems, each robot must behaves by itself according to the its states and environments, and if necessary, must cooperates with other robots in order to carry out a given task. Therefore it is essential that each robot has both learning and evolution ability to adapt the dynamic environments. In this paper, reinforcement learning method using many SVM based on structural risk minimization and distributed genetic algorithms is proposed for behavior learning and evolution of collective autonomous mobile robots. By distributed genetic algorithm exchanging the chromosome acquired under different environments by communication each robot can improve its behavior ability. Specially, in order to improve the performance of evolution, selective crossover using the characteristic of reinforcement learning that basis of Cascade SVM is adopted in this paper.

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