• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.42.1-42
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• 2001

This paper presents a fuzzy-based method for classification skin color object in a complex background under varying illumination. Parameters of fuzzy rule base are generated using a genetic algorithm(GA). The color model is used in the YCbCr color space. We propose a unique fuzzy system in order to accommodate varying background color and illumination condition. This fuzzy system approach to skin color classification is discussed along with an overview of YCbCr color space.

• Journal of Broadcast Engineering
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• v.1 no.2
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• pp.176-187
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• 1996

This paper deals with the accurate estimation of 3- D pose (position and orientation) of a moving object with reference to the world frame (or robot base frame), based on a sequence of stereo images taken by cameras mounted on the end - effector of a robot manipulator. This work is an extension of the previous work[1]. Emphasis is given to the 3-D pose estimation relative to the world (or robot base) frame under the presence of not only the measurement noise in 2 - D images[ 1] but also the camera position errors due to the random noise involved in joint angles of a robot manipulator. To this end, a new set of discrete linear Kalman filter equations is derived, based on the following: 1) the orientation error of the object frame due to measurement noise in 2 - D images is modeled with reference to the camera frame by analyzing the noise propagation through 3- D reconstruction; 2) an extended Jacobian matrix is formulated by combining the result of 1) and the orientation error of the end-effector frame due to joint angle errors through robot differential kinematics; and 3) the rotational motion of an object, which is nonlinear in nature, is linearized based on quaternions. Motion parameters are computed from the estimated quaternions based on the iterated least-squares method. Simulation results show the significant reduction of estimation errors and also demonstrate an accurate convergence of the actual motion parameters to the true values.

• Journal of the Korean Society of Industry Convergence
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• v.19 no.1
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• pp.1-9
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• 2016

In this paper, we propose a new learning control scheme for various walk motion control of biped robot with same learning-base by neural network. We show that learning control algorithm based on the neural network is significantly more attractive intelligent controller design than previous traditional forms of control systems. A multi layer back propagation neural network identification is simulated to obtain a dynamic model of biped robot. Once the neural network has learned, the other neural network control is designed for various trajectory tracking control with same learning-base. The biped robots have been received increased attention due to several properties such as its human like mobility and the high-order dynamic equation. These properties enable the biped robots to perform the dangerous works instead of human beings. Thus, the stable walking control of the biped robots is a fundamentally hot issue and has been studied by many researchers. However, legged locomotion, it is difficult to control the biped robots. Besides, unlike the robot manipulator, the biped robot has an uncontrollable degree of freedom playing a dominant role for the stability of their locomotion in the biped robot dynamics. From the simulation and experiments the reliability of iterative learning control was illustrated.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.4
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• pp.355-362
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• 2016

In order to secure the stability against strong earthquakes, isolation devices on the existing nuclear power plant have been introduced. By applying the isolation device on structures, it is possible to isolate structures from the ground motion. Therefore, the natural frequencies of the structures become longer, and the responses of the structures due to the ground motion decrease. Especially, when designing the nuclear power plant, it is important to ensure the safety of internal devices as well as the nuclear power plant itself. The floor response spectrum is commonly used in designing the internal devices. In this research, floor response spectrum is evaluated and the effect of second hardening behavior is investigated by performing earthquake analysis.

• Journal of Biomedical Engineering Research
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• v.25 no.6
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• pp.511-517
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• 2004

The existing rehabilitation systems were developed to exercise specific joints only. Therefore rehabilitating the various joints of human, various kinds of devices are need. To overcome these defects, this paper proposed the CMRS, an integrated system that performs various rehabilitation exercises. The characteristics of motion and the positions between human body and the system were investigated with the kinematics analysis of upper and lower limb of human body. We presented a proper mechanism to develop a rehabilitation device on the base of the study and studied the relative positions between head part and human joints. Through the simulations, the possibility of rehabilitation system was verified. And the base frame was also developed for convenient and stable position control. Finally, the CMRS was developed as an 8 degree of freedom mechanism. It is expected that the CMRS will be applied to the rehabilitations of various joints.

• Computers and Concrete
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• v.26 no.6
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• pp.483-495
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• 2020

Dams are vital infrastructures that are expected to maintain their stability during seismic excitations. Accordingly, cemented material dams are an emerging type, which are being increasingly used around the world owing to benefiting from advantages of both earth-fill and concrete gravity dams, which should be designed safely when subjected to strong ground motion. In the present paper, the seismic performance of a cemented sand and gravel (CSG) dam is assessed using incremental dynamic analysis (IDA) method by accounting for two failure modes of tension cracking and base joint sliding considering the dam-reservoir-foundation interactions. To take the seismic uncertainties into account, the dam is analyzed under a suite of ground motion records and then, the effect of friction angle for base sliding as well as deformability of the foundation are investigated on the response of dam. To carry out the analyses, the Cindere dam in Turkey is selected as a case study, and various limit states corresponding to seismic performance levels of the dam are determined aiming to estimate the seismic fragilities. Based on the results, sliding of the Cindere dam could be serious under the maximum credible earthquake (MCE). Besides, dam faces are mostly to be cracked under such level of intensity. Moreover, the results indicate that as friction angle increases, probability of sliding between dam and foundation is reduced whereas, increases tensile cracking. Lastly, it is observed that foundation stiffening increases the probability of dam sliding but, reduces the tensile damage in the dam body.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.9
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• pp.1795-1802
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• 2009

Motion based serious game is a new style of game and exercise using hands, arms, head and whole body. At that time gamer's reachable movement space is an important game space and interaction happening place. We propose efficient game spatial division and analysis algorithm that gives special information for collision avoidance of game objects. We devide into 9 parts of game space and check the enemy position and upper, down, left and right side movement information of gamer and calculate optimal path for collide avoidance of the enemy. To evaluate the method, we implemented a motion base serious game that consists of a web cam, a player, an enemy, and we obtained some valid results of our method for the collision avoidance. The resole demonstrated that the proposed approach is robust. If movement information is in front of enemy, then the enemy waits and finds the place and runs to avoid collision. This algorithm can be used basic development of level control and effective interaction method for motion based serious game.

• The Research Journal of the Costume Culture
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• v.6 no.2
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• pp.66-76
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• 1998

In order to investigate the effect of shoulder pad affecting the arm movement, eleven women volunteers of standard body whose age is from eighteen to twenty-four(x±1σ) were chosen and this experiment had done according to front-vertical motion, side-vertical motion and horizontal motion of upper limps for tow different materials of shoulder pad(sponge, non-woven) and four different thickness of shoulder pad(0.6cm, 0.8cm, 1.2cm). On the base of this, this study, when putting on shoulder pad, try to find the reform method of shoulder part pattern. The results are as follows. 1. When puting on shoulder pad to blouse pattern to rise shoulder pad for rate of two-third per thickness is seemingly the best for sensory evaluation. So, when putting on shoulder pad, we understand that in order to improve sensory evaluation. So, when putting on shoulder pad, we understand that in order to improve sensory evaluation of clothes, when that, rising shoulder pad for ate of two-third per thickness is the best. 2. From the results of measure of functional volume and physiological value for functionality evaluation according to thickness and material, motion of shoulder pad, 1.2 cm thickness and non-woven material is evaluated the worst for functionality. 3. From the results of sensory evaluation and functionality evaluation of material of shoulder pad, sponge material is superior for functionality but not for sensory evaluation, non-woven material is superior for sensory evaluation non-woven material is superior for sensory evaluation but not for functionality. So, think that it had better use sponge material for functional clothes, non-woven material for aesthetical clothes. 4. From the results of functionality of clothes, when putting on shoulder pad, the worst discomfortable parts are the armpit part and the shawl part, functionality of these part shoulder be reformed.

• Journal of Korea Multimedia Society
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• v.15 no.4
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• pp.485-491
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• 2012

This paper proposes 'Coding Unit Tree' based on quadtree efficiently with motion vector to represent splitting information of a Coding Unit (CU) in HEVC. The new international video coding, High Efficiency Video Coding (HEVC), adopts various techniques and new unit concept: CU, Prediction Unit (PU), and Transform Unit (TU). The basic coding unit, CU is larger than macroblock of H.264/AVC and it splits to process image-based quadtree with a hierarchical structure. However, in case that there are complex motions in CU, the more signaling bits with motion information need to be transmitted. This structure provides a flexibility and a base for a optimization, but there are overhead about splitting information. This paper analyzes those signals and proposes a new algorithm which removes those redundancy. The proposed algorithm utilizes a type code, a dominant value, and residue values at a node in quadtree to remove the addition bits. Type code represents a structure of an image tree and the two values represent a node value. The results show that the proposed algorithm gains 13.6% bit-rate reduction over the HM-1.0.

• Geomechanics and Engineering
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• v.8 no.5
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• pp.663-674
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• 2015

Many seismically vulnerable regions in India and worldwide are located on deep soil deposits which extend to several hundred meters of depth. It has been well recognized that the earthquake shaking is altered by geological conditions at the location of building. As seismic waves propagates through uppermost layers of soil and rock, these layers serve as filter and they can increase the duration and amplitude of earthquake motion within narrow frequency bands. The amplification of these waves is largely controlled by mechanical properties of these layers, which are function of their stiffness and damping. Stiffness and damping are further influenced by soil type and thickness. In the current study, an attempt has been made to study the seismic site response of deep soils. Three hypothetical homogeneous soil models (e.g., soft soil, medium soil and hard soil) lying on bedrock are considered. Depth of half space is varied from 30 m to 2,000 m in this study. Controlled synthetic motions are used as input base motion. One dimensional equivalent linear ground response analyses are carried out using a computer package DEEPSOIL. Conventional approach of analysing up to 30 m depth has been found to be inadequate for deep soil sites. PGA values are observed to be higher for deeper soil profiles as compared to shallow soil profiles indicating that deeper soil profiles are more prone to liquefaction and other related seismic hazards under earthquake ground shaking. The study recommends to deal the deeper soil sections more carefully for estimating the amplification factors for seismic hazard assessment at the surface.