• Title/Summary/Keyword: auxiliary problem

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An Anti-Sway Control System Design Based on Simultaneous Optimization Design Approach (동시최적화 설계기법을 이용한 항만용 크레인의 흔들림 제어계 설계)

  • Kim, Young-Bok;Moon, Duk-Hong;Yang, Joo-Ho;Chae, Gyu-Hoon
    • Journal of Ocean Engineering and Technology
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    • v.19 no.3
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    • pp.66-73
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    • 2005
  • The sway motion control problem of a container hanging on the trolley is considered in this paper. In the container crane control problem, the main issue involves suppressing the residual swing motion of the container at the end of acceleration, during deceleration, or for an unexpected disturbance input. For this problem, in general, many trolley motion control strategies are introduced and applied. In this paper, we introduce and synthesize a swing motion control system, in which a small auxiliary mass is installed on the spreader. In this control system, the actuator reacting against the auxiliary mass applies inertial control forces to the container to reduce the swing motion in the desired manner. In many studies, the controllers used to suppress the vibration have been synthesized for the given mathematical model of plants. In many cases, the designers have not been able to utilize the degree of freedom to adjust the structural parameters for the control object. To overcome this problem, so called "Structure/Control Simultaneous Method" is used. From this, in this paper the simultaneous design method is used to achieve optimal system performance. And the experimental result shows that the proposed control strategy is useful, to the case of that the controlled system is exposed to the uncertainties and, robust to disturbances like wind.

Electromagnetic Analysis on the Torque Motor of Servo Valve for the Fuel Supply System of Auxiliary Power Unit (보조 동력 장치 연료 공급용 서보밸브의 토크모터 전자기 해석)

  • Chang, Se-Myong;Jang, Gang-Won;Jeong, Heon-Sul;Rhee, Dong-Ho
    • Journal of Aerospace System Engineering
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    • v.1 no.3
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    • pp.7-12
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    • 2007
  • As a main part of an utility helicopter, the APU(Auxiliary Power Unit) has a solenoid valve system operated with a torque motor, which controls the flow rate in the fuel supply system. In this paper, we solved the Maxwell potential equations to analyze the electromagnetic force in the torque motor, and some additional analytic methods are used to compute the quantity of torque produced by the torque motor for the given circuit current. For the convenience, small displacement is assumed, and only magneto-static problem is considered for the two-dimensional cross section. The result will be compared with the three-dimensional analysis that will be studied in the near future.

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Control of a Segway with unknown control coefficient and input constraint

  • Park, Bong Seok
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.16 no.2
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    • pp.140-146
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    • 2016
  • This paper proposes a control method of the Segway with unknown control coefficient and input saturation. To design a simple controller for the Segway with the model uncertainty, the prescribed performance function is used. Furthermore, an auxiliary variable is introduced to deal with unknown time-varying control coefficient and input saturation problem. Due to the auxiliary variable, function approximators are not used in this paper although all model uncertainties are unknown. Thus, the controller can be simple. From the Lyapunov stability theory, it is proved that all errors of the proposed control system remain within the prescribed performance bounds. Finally, the simulation results are presented to demonstrate the performance of the proposed scheme.

Character of PWM DC-DC Converter for Conduction Loss Reduction and Efficiency Rise (전도손실 저감 및 효율 상승을 위한 PWM DC-DC 컨버터의 특성)

  • Kim, M.Y.;Kim, H.J.;Kim, C.Y.;Lyu, J.Y.;Kim, S.W.
    • Proceedings of the KIEE Conference
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    • 2007.11c
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    • pp.125-127
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    • 2007
  • Presented increase and so on of switch stress and switching dissipation and EMI that is happened in general PWM converter and in this study to solve problem the resonance energy return to life rate and new active snubber PWM converter because do maximization. Active snubber PWM converter that try adds auxiliary switch and resonance capacitor, diode to existing converter under all switching conditions turn on/off Minimised switching dissipation that occur. Reduced harmonic components absorbing station recovery electric current that happen to snubber diode inserting diode and resistance. And decreased peak current that is happened in auxiliary switch arranging resonance capacitor and inductor properly, Certified effect that efficiency rises about 2.5[%] more than existent PWM converter in rated load through an experiment.

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A Diode Bridge-type ZVT Inverter for Induction Motor Drive Application (유도 전동기 구동용 다이오드 브릿지-타입 ZVT 인버터)

  • 이성룡;고성훈;권순신;송인석
    • Proceedings of the KIPE Conference
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    • 1999.07a
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    • pp.295-298
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    • 1999
  • In this paper, the diode bridge-type ZVT(Zero-Voltage Transition) inverter is proposed. It consists of one auxiliary switch, three resonant inductors and six blocking diodes. So, the advantage of the proposed topology is the reduction of the auxiliary switch. The topology of the proposed ZVT inverter is analyzed with a description of the control conditions based on the load current. Therefore, this paper two control algorithms were discussed. A variable resonant pattern control algorithm by using load current feedback and a resonant period control algorithm by using resonant inductor current feedback is proposed in order to achieve the ZVT switching condition in full control range and the reducing current spike main switches cause by reverse recovery problem.

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Obstacle Avoidance and Playing Soccer in a Quadruped Walking Robot (4족 보행 로봇의 장애물 회피와 축구하기)

  • Seo, Hyeon-Se;Sung, Young Whee
    • IEMEK Journal of Embedded Systems and Applications
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    • v.7 no.3
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    • pp.143-150
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    • 2012
  • In this paper, we introduce an intelligent quadruped walking robot that can perform stable walking and a couple of intelligent behaviors. The developed robot has two sets of ultrasonic sensors and six sets of infrared sensors and can perform obstacle avoidance by detecting obstacles and estimating the distances and directions of those obstacles. The robot also has a stereo camera and can paly soccer by detecting a ball and estimating the 3 dimensional coordinates of the ball. In performing those intelligent behaviors, the robot needs to have the capability of generating its walking patterns, solving the inverse kinematics problem, and interfacing several sensors in realtime. Therefore we designed a hierarchical controller that consists of a main controller and an auxiliary controller. The main controller is a 32-bit DSP that can perform fast floating-point opertaion and the auxiliary one is a 8-bit micro-controller. We showed that the developed quadruped walking robot successfully perform those intelligent behaviors through experiments.

Single Sustaining Driver for AC-PDP employing Voltage Stress Reduction Technique (전압 스트레스 저감 기법을 적용한 AC-PDP를 위한 단일 유지 구동 회로)

  • Park Ki-Bum;Choi Seong-Wook;Kim Chong-Eun;Moon Gun-Woo;Youn Myung-Joong
    • Proceedings of the KIPE Conference
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    • 2006.06a
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    • pp.88-90
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    • 2006
  • Conventional sustaining driver (SD) of plasma display panel (PDP) employing auxiliary circuits on both side of a H-bridge inverter increases volume of PDP with cost. To solve this problem, a new single sustaining driver (SSD), which utilize only one side of auxiliary circuit is proposed. Moreover, using the voltage stress reduction technique (VSRT), the proposed SSD effectively reduces switch voltage stress with a simple structure.

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A Laser Doppler Vibrometer Featured with the In-housed Mechanism for Adaptive Compensation of Body Vibration (자체진동의 보상을 위한 레이저 도플러 계측 신호 적응 진동보상 기법 연구)

  • Lee, Jae-Sik;Chang, Tae-Gyu;Kim, Jae-Hwa;Kim, Ho-Seong;Kang, Min-Sig
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.50 no.8
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    • pp.392-399
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    • 2001
  • This paper presents an auxiliary beam-assisted adaptive compensation technique applied to alleviate the problem of LDV's body vibration. The LMS algorithm is applied to adaptively compensate the body vibration utilizing the reference signal provided by the auxiliary beam. The usefulness of the proposed technique is verified via computer simulations performed for diverse types of target signals and body vibration.

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PromoterWizard: An Integrated Promoter Prediction Program Using Hybrid Methods

  • Park, Kie-Jung;Kim, Ki-Bong
    • Genomics & Informatics
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    • v.9 no.4
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    • pp.194-196
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    • 2011
  • Promoter prediction is a very important problem and is closely related to the main problems of bioinformatics such as the construction of gene regulatory networks and gene function annotation. In this context, we developed an integrated promoter prediction program using hybrid methods, PromoterWizard, which can be employed to detect the core promoter region and the transcription start site (TSS) in vertebrate genomic DNA sequences, an issue of obvious importance for genome annotation efforts. PromoterWizard consists of three main modules and two auxiliary modules. The three main modules include CDRM (Composite Dependency Reflecting Model) module, SVM (Support Vector Machine) module, and ICM (Interpolated Context Model) module. The two auxiliary modules are CpG Island Detector and GCPlot that may contribute to improving the predictive accuracy of the three main modules and facilitating human curator to decide on the final annotation.

Study on single/three phase converter for motor applications of rural district (농어촌 동력용 전동기구를 위한 단상/3상변환기의 개발에 관한 연구)

  • 황영문;조철제
    • 전기의세계
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    • v.25 no.4
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    • pp.68-72
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    • 1976
  • This study is initiated to solve the problem that the development of an electric machine to drive heavy horse-power load required in the rural district, where only single phase supply is available, is very urgent. As a method for this purpose, the single/three phase converter by single phase induction machine with a tapped auxiliary winding, running unloaded mechanically under single-phase source and supplying three-phase output to a loaded 3-phase induction motor, is devised and the pilot machine is put into test. Analysis based on hybrid equivalent circuit for the phase converter and symmertical component theory for the 3-phase load motor and practical experiment result in that optimum auxiliary winding ratio is to be 1.25 rather than theoretical .root.3/2 in order to keep the voltage unbalance ratio of 3-phase output from the converter as low as possible in both cases of starting and running the load motor.

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