• Journal of Institute of Control, Robotics and Systems
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• v.11 no.9
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• pp.816-821
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• 2005

The remote operation of $4\~5$ cranes for container loading/unloading at a port by one operator will dramatically improve loading/unloading efficiency through productivity increase, cost reduction, and so on. This study develops a remote crane control system for container loading/unloading yard cranes. First, a wireless video and audio system to transmit views and sounds of the working field is designed by using 3 web cameras and a microphone. Next, a RSVP-based multi-path reservation method is presented with a view to improving the quality of service in the communication network for remote control. Simulation results show that a RSVP-based multi-path reservation can enhance the reservation success rate in the TCP/IP network.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.3
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• pp.1-12
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• 2003

The complexity of the papermaking system accelerates interactions between a large number of variables involved. The process operation, therefore, is subject to frequent perturbations by disturbance. Dynamic modelling is a useful tool for characterizing the transient behavior and selecting the best control strategies to reject disturbances. In this study we developed a dynamic simulation model of a fine paper production process, which consists of stock preparation, wire sections, white water circulations, and broke system. It focused on dynamic simulation in its role for developing control strategies and studying control loop dynamics related to filler loading for ash control. The results emphasized the importance of filler-loading position and length of control loop for rapid ash control and process stabilization.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1603-1608
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• 2003

Multiple robotics systems with several sub-chains have a characteristic that grasp a common object with internal loading not to loose the grip. The investigation for the internal loading of a triple manipulator has been few as compared to a dual manipulator. In this paper, type of the internal loading for a triple manipulator system is investigated through analysis of the null space of the system. Several types of the internal loading are shown for general planar and spatial type triple robots, which rigidly grasp the common object. The general scheme is applied to analysis of the internal loading for the three-fingered and three-legged robots having a point contact with the grasped object.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.4
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• pp.95-100
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• 2004

This paper represents the development of a CLS(Control Loading System) for a target a airplane (KT-1) with mechanical linkage reversible flight control system. The system is composed of mechanical frame, controller, sensing part to measure the force from the stick, driving system generating the reaction forces. The DS1103 DSP(Digital Signal Processor) of the dSpace Corp. was used as the controller. The control algorithm of the CLS and the operational environment including monitoring software and evaluation tools are described. The evaluation of the system was conducted according to the requirement specification. The results of the test were analyzed by comparing with the actual data of the target airplane.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.5
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• pp.750-756
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• 2017

This paper presents a method for DC voltage control of HVDC system connection of offshore wind farms. In the event of fault in AC grid, HVDC system need to meet LVRT regulations. When HVDC system meet LVRT regulation, unbalance is caused between power input and power output for DC link. Therefore, LVRT regulation lead to DC voltage increase of HVDC system. To control the DC voltage increase, the chopper resistor can be suggested. In this paper, DC voltage suppression is proposed using chopper resistor and de-loading. The effectiveness of the chopper resistor was verified using PSCAD/EMTDC.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.2
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• pp.103-108
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• 2005

Loading/Unloading task in the real industry is performed by crane, but most of the loading/unloading task with the weight of 5kg∼30kg is done by human workers and this kind of work causes industrial disaster of workers. Therefore it is necessary to develop low cost loading/unloading manipulator system to prevent this kind of industrial accidents. This paper is concerned with the design and fabrication of 2 axis pneumatic manipulators using on/off solenoid valves and accurate position control without respect to the external load and low damping in the pneumatic rotary actuator. To overcome the change of external load, switching of control parameter using LVQNN (Learning Vector Quantization Neural Network) is newly applied, which estimates the external loads in the pneumatic cylinder. As an underlying controller, a state feedback controller using position, velocity and acceleration is applied to the switching control system. The effectiveness of the proposed control algorithms are demonstrated through experiments of pneumatic cylinder with various loads.

• Structural Engineering and Mechanics
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• v.12 no.2
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• pp.157-168
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• 2001

In this paper, experimental investigation into the behavior of reinforced concrete (RC) columns tested under large lateral displacement with four different types of loading arrangements is presented. Each loading arrangement has a different system for controlling the consistency of the loading condition. One of the loading arrangements used three units of link mechanism to control the parallelism of the top and bottom stub of column during testing, and the remaining employed eight hydraulic jacks for the same purpose. The loading systems condition used in this investigation were similar to the actual case in a moment-resisting frame where the tested column was displaced in a double curvature. Ten model column specimens, divided into four series were prepared. Two columns were tested monotonically until collapse, and unless failure took place at an earlier stage of loading, the remaining eight columns were tested under cyclic loading. Test results indicated that the proposed system to keep the top and bottom stubs parallel during testing performed well.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.203-206
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• 1996

The purpose of this paper is to find how to determine the parameters of the basic control system design such as hinge moment coefficients and to display the controllability of the ChangCong-91. Since the estimation from the flight test of real aircraft is the most reliable, we performed the flight test of ChangGong-91 to get the various parameters such as velocity, height, control force, control surface deflection, 3 axis acceleration, 3 axis angular rate, pitch angle, angle of attack temperature and so on. We recorded the flight test data in VHS tapes and stored them to personal computer using A/D(analog to digital) converter. Flight test was done in various conditions, and the acquired data was processed with parameter identification method such as least square method. These data will be utilized for the development of Autopilot System design and Control Loading System design.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.7
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• pp.713-718
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• 2006

Supersonic jet fighter aircraft have several different weapon loading configuration to support air-to-air combat and air-to-ground delivery of weapon modes. Especially, asymmetric loading configurations could result in decreased handling qualities for the pilot maneuvering of the aircraft. The design of the T-50 lateral-directional roll axis control laws change from beta-betadot feedback structure to simple roll rate feedback structure and gains such as F-16 in order to improve roll-off phenomena during pitch maneuver in asymmetric loading configuration. Consequently, it is found that the improved control law decreases the roll-off phenomenon in lateral axes during pitch maneuver, but initial roll response is very fast and wing pitching moment is increased. In this paper, we propose the lateral control law blending between beta-betadot and simple roll rate feedback system in order to decreases the roll-off phenomenon in lateral axes during pitch maneuver without degrading of roll performance.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.822-828
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• 2001

Three-phase four-wire electrical distribution systems are widely employed in manufacturing plants, commercial and residential buildings. Due to the nonlinear loads connected to the distribution system, the neutral conductor carries excessive harmonic currents even under balanced loading since the triplen harmonics in phase currents do not cancel each other. This may result in wiring failure of the neutral conductor and overloading of the distribution transformer. In response to these concerns, a cost-effective neutral current harmonic suppressor system has been proposed [6]. This paper proposes an improved control method for the harmonic suppressor system under unbalanced load conditions. The proposed control method compensates for only the harmonic components in the neutral conductor, and the zero-sequence fundamental component due to unbalanced loading is prevented from flowing through the harmonic suppressor system. This remedies overloading and power loss of the system. The experimental results on a prototype validate the proposed control approach.