• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2006.11a
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• pp.336-339
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• 2006

모델 예측 제어 시스템은 이동 제어 구간에서 원하는 출력과 예측된 출력의 차이를 최소화하는 현재의 제어 입력을 적용하는 방식을 사용한다. 제약조건이 있는 경우이거나 비선형 시스템 문제의 경우는 주어진 함수를 최소화하는 최적화 문제를 풀기가 힘들다. 본 논문에서는 모델 예측 제어 시스템의 최적화 문제를 실수 코딩 유전 알고리즘을 이용하여 효율적으로 구할 수 있음을 보인다. 또한 실수코딩 유전알고리즘이 여러 가지 면에서 디지털코딩 유전알고리즘보다 더 자연스럽고 유리함을 모의실험을 통해 보인다.

• Journal of Power Electronics
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• v.16 no.5
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• pp.1773-1780
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• 2016

This paper proposes a wide air-gap control method for the multi-module permanent magnet linear synchronous motor (MM-PMLSM) based on independent vector control. In particular, the MM-PMLSM consists of symmetrical multi-module and multi-phase structures, which are basically three-phase configurations without a neutral point, unlike conventional three-phase machines. In addition, there are no additional magnetic levitation windings to control the normal force of the air-gap between each stator and mover. Hence, in this paper, a dq-axis current control applying a d-q transformation and an independent vector control are proposed for the air-gap control between the two symmetric stators and mover of the MM-PMLSM. The characteristics and control performance of the MM-PMLSM are analyzed under the concept of vector control. As a result, the proposed method is easily implemented without additional windings to control the air-gap and the mover position. The effectiveness of the proposed independent vector control algorithm is verified through experimental results.

• International Journal of Aeronautical and Space Sciences
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• v.6 no.2
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• pp.1-16
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• 2005

Adaptive control methods are studied for the Satellite to isolate vibration in spite of the nonlinear system dynamics and parameter uncertainties of disturbance. First, a centralized control scheme is developed based on the particle swarm optimization(PSO) algorithm and feedback theory to automatically tune controller gains. A simulation study of a 3 degree-of-freedom device was conducted to evaluate the performance of the proposed control scheme. Next, since a centralized control scheme is hard to construct model dynamics and not goad at performance when controller and systems environment are easily changed, a decentralized control scheme is presented to avoid these defects of the centralized control scheme from the point of view of production and maintenance. It is based on the adaptive control methodologies to find PID controller parameters. Experiment studies were conducted to apply the adaptive control scheme and evaluate the performance of the proposed control scheme with those of the conventional control schemes.

• Journal of Korean Medicine Rehabilitation
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• v.18 no.3
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• pp.51-65
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• 2008

Objectives : In order to investigate the effects of Soongijeseub-bang(Shunqichushi-fang)(here in after referred to SJB) on the obese gene and obese inhibitory, on C57BL/6 mice were induced by high fat diet. Methods : C57BL/6 mice were divided into three groups(normal, high fat diet with control, high fat diet with SJB extract) and fed for 15 weeks. And observed that, body weight change, final increase of body weight, the weight change of the adipocytes, the level change of ALT, AST, creatinine, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride, NEFA, glucose, the expression of ${\beta}3AR$, leptin, and $TNF-{\alpha}$ gene in primary adipocytes and adipocytes tissue. Results : The following results were obtained in this study. 1. SJB 500 mg/kg extract group showed considerable decrease in weight, the final increase of weight and the amount of adipocyte in weight. 2. All experimental group showed that the amount of ALT, AST, total cholesterol, LDL-cholesterol, triglyceride and NEFA were decreased considerably. SJB 500 mg/kg extract group showed the amount of HDL-cholesterol and leptin were increased considerably. 3. All experimental group showed that the revelation of ${\beta}3AR$ in primary adipose cell and 3T3-L1 cell were increased considerably, and that the revelation of leptin in primary adipose cell and 3T3-L1 cell were decreased considerably. SJB $100{\mu}{\ell}/m{\ell}$ extract group showed that the revelation of $TNF-{\alpha}$ were decreased considerably. 4. SJB 500 mg/kg extract group showed that the size of adipocyte in adipocytes tissue were decreased. 5. All experimental group showed that the adipose vacuoles in liver tissue were decreased considerably. Conclusions : Comparison of the results for this study showed that SJB is effective on obesity care and has obese-inhibitory effects in obese mouse induced by high fat diet. So it is respected that the clinical application of SJB can help the treatment of obesity.

• Journal of Oral Medicine and Pain
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• v.39 no.2
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• pp.46-54
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• 2014

Purpose: The aim of this study was to investigate the effects of academic stress and self-control ability on temporomandibular disorder (TMD) of adolescents. Methods: Participants were 1,112 teenagers who were 1st grade students of middle and high school. After checking their academic stress and self-control ability through a self-administrated questionnaire, the students were examined their TMD by two trained dentists. We drew a comparison the level of their academic stress and self-control ability between the students with and without TMD. We divided them to four groups according to the level of academic stress and self-control. And we checked prevalence of TMD in each level. Results: The group of students with TMD was higher academic stress score level than the students without TMD (p<0.05). And they had lower self-control score level than the students without TMD (p<0.05). Even if they were under the same academic stress, the group of students with higher self-control score was less TMD prevalence than the students with lower score. Conclusions: Academic stress makes adolescents to increase TMD and high ability of self-control makes them to decrease it. And these tendencies are seemed to have a great influence on young male student.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1993.04a
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• pp.140-146
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• 1993

Active noise control uses the intentional superposition of acoustic waves to create a destructive interference pattern such that a reduction of the unwanted sound occurs. In active noise control system the choice of a control structure and design of the controller are the main issues of concern. In real acoustic fields there are a vast number of noise sources with time-varying nature and the characteristics of transducers and the geometric set-up of control system are subject to change. Accordingly the control system should be designed to adapt such circumstances so that required level of performance is maintained. In this paper, the adaptive control algorithm for self-tuning adaptive controller is presented for the application in active noise control system. Self-tuning is a direct integration of identification and controller design algorithm in such a manner that the two processes proceed sequentially. The least mean square algorithm was used for the identification schemes and adaptive weighted minimum variance control algorithm was applied for self-tuning controller. Computer simulation results for self-tuning feedback controller are presented. And simulation results was shown to be useful for the situation in which the periodic noise sources act on the acoustic field.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.12
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• pp.1170-1176
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• 2010

This study addresses adaptive control of UAVs(Unmanned Aerial Vehicles) pitch-axis maneuver. The MRAC(Model Referenced Adaptive Control) approach is employed to accommodate uncertainties which are introduced by feedback linearization of pitch attitude control by elevator input. The model uncertainty is handled by adaptation laws which update model parameters while the UAV is under control by the feedback control law. Steady-state pitch attitude achieved by the stabilizing control law is derived to provide insight on the closed-loop behavior of the controlled system. The proposed idea is free of linearization, gain-scheduling procedures, so that one can design high maneuverability of UAVs for pitching motion in the presence of significant model uncertainty.

• Computational Structural Engineering : An International Journal
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• v.3 no.1
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• pp.61-68
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• 2003

A recently developed semi-active control system employing magneto-rheological (MR) fluid dampers is applied to vibration control of a wind excited tall building. The semi-active control system with MR fluid dampers appears to have the reliability of passive control devices and the adaptability of fully active control systems. The system requires only small power source, which is critical during severe events, when the main power source may fail. Numerical simulation studies are performed to demonstrate the efficiency of the MR dampers on the third ASCE benchmark problem. Multiple MR dampers are assumed to be installed in the 76-story building. Genetic algorithm is applied to determine the optimal locations and capacities of the MR dampers. Clipped optimal controller is designed to control the MR dampers based on the acceleration feedback. To verify the robustness with respect to the variation of the external wind force, several cases with different wind forces are considered in the numerical simulation. Simulation results show that the semi-actively controlled MR dampers can effectively reduce both the peak and RMS responses the tall building under various wind force conditions. The control performance of the MR dampers for wind is found to be fairly similar to the performance of an active tuned mass damper.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1263-1266
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• 1997

In a fault-tolerant modern manufacturing systms characterized by the configuration, in which automated redundant machines prone to unexpected failures are interconnected with other complex subsystems such as AGV's, robots, computer control systems to produce complete parts, faulures together with repairs and reconfigurations should be considered as the three basic events to be modeled for computing the performance of manufacturing systems. In this papre, transient analysis is applied to modular cell manufacturing systems form a performability viewpoint whose modeling adantage is that various performanc e measures can be evaluated compositely in the context of application. The hypothertical modular cells are modeled firstly with hybrid decomposition method and availability measures as special cases of performability are computed and comments on performabililty modeling analysis are mentioned.

• International Journal of Control, Automation, and Systems
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• v.4 no.2
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• pp.227-235
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• 2006

For a sophisticated humanoid that explores and learns its environment and interacts with humans, anthropomorphic physical behavior is much desired. The human vision system orients each eye with three-degree-of-freedom (3-DOF) in the directions of horizontal, vertical and torsional axes. Thus, in order to accurately replicate human vision system, it is imperative to have a simulator with 3-DOF end-effector. We present a 3-DOF anthropomorphic oculomotor system that reproduces realistic human eye movements for human-sized humanoid applications. The parallel link architecture of the oculomotor system is sized and designed to match the performance capabilities of the human vision. In this paper, a biologically-inspired mechanical design and the structural kinematics of the prototype are described in detail. The motility of the prototype in each axis of rotation was replicated through computer simulation, while performance tests comparable to human eye movements were recorded.