• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.546-551
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• 2006

It considered the population decrease and becoming older in age of the Rural area and operates by unmaned-non power which self-controlled gate developed. The operational principal used a buoyancy and when water level in the canal arrived to the set water level, in order for gate to be opened. The plate in order to fix to the shape in the canal which begs, it did in the quadrilateral and the rainfall it is sour intensively, canal bank comfort plate in order to ascend completely, it designed. The result which establishes Self-controlled gate, the gate upstream 1km until degree there was water level synergistic effect. It developed 4 as the research project and it established in Ah San city, and it establishes the Self-controlled gate of $B3.2m{\times}H2.4m$ size in Damyang and 100ha it does water supply in the rice field.

• Tribology and Lubricants
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• v.24 no.1
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• pp.34-43
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• 2008

In this paper, an actively controlled aerostatic bearing is studied to overcome the defects of air bearing such as low stiffness and damping coefficients. The actively controlled aerostatic bearing is composed of aerostatic bearings, non-contact type of displacement sensors, piezoelectric actuators and controllers. The cylindrical capacitance sensor (CCS) is used as the displacement sensor. The reason for using CCS instead of the commercial gap sensor is that it can give us the pure error motion of the spindle because it removes the roundness error or the geometric errors in the spindle. The controller is designed by the state space equation and quadratic optimal control theory. The characteristic data of the actively controlled aerostatic bearing system in the frequency domain are presented and the stiffness and damping coefficients of the bearing are mentioned. This paper shows the possibility to reduce the motion error up to 6000 rpm.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.193-195
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• 2006

In this study, we developed an active controlled ankle-foot orthosis(AAFO) which can control the dorsiflexion/plantarflexion of the ankle joint during gait to prevent foot drop and toe drag for paralysis patients. To prevent dropping foot after heel strike, ankle joint was actively controlled to minimize forefoot collision with the ground. It was also controlled to provide toe clearance and to help push-off during late stance. The 3D gait analysis was performed on two healthy subjects equipped with the developed AAFO to compare with the normal gait and the conventional AFO gait. In the developed AAFO gait, differently from the conventional AFO gait, significant push-off was observed during pre-swing and the maximum flexion moment during pre-swing phase was similar to that of normal gait. A remarkable dorsiflexion also occurred during initial swing. These results indicated that the developed AAFO could have certain clinical benefits to prevent foot drop for paralysis patients, compared to conventional AFOs.

• English Language & Literature Teaching
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• v.12 no.4
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• pp.117-138
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• 2006

The purpose of this study is to increase students' interest in the subject of English, which has been led by some mannerism, and to improve the students' basic scholastic ability and self-controlled problem solving, through adopting an individualized Web Based Instruction(WBI) as a concrete and practical learning method. In order to achieve this, an individualized Web Based Instruction(WBI) homepage has been developed to be applied experimentally to the field of middle school education for 8 months, and a research has been made on its effects on the students' interest in English along with the improvement of English. Two groups which showed almost the same interest were selected as a controlled group and an experimental one. Individualized Web Based Instruction was applied to the experimental group, while the controlled group was not instructed according to student ability. The controlled group was taught using CD added with the textbook. As a result of T-test, the students in the experimental group showed more improvement in communicative competence than those in the controlled group.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.2
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• pp.235-240
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• 2013

This paper presents a disposable microfluidic infusion pump using the restoring force of elastomeric membrane of Polydimethylsiloxane. Microfluidic infusion pump consists of hydraulic resistance control part, elastomeric blister actuator part, drug inlet and outlet. Expanded elastomeric blister actuator continuously pushes liquid in the chamber to outlet. At same time, microchannel diameter near the outlet was controlled by thin elastomeric membrane in hydraulic resistance control part. Eventually flow rate of infused liquid is controlled by air pressure. In experimental study, the amount of the filled liquid in the blister is precisely controlled by the height of the blister. Flow rate of infused liquid could be controlled, that is, controlled release of the drug over time was possible by adjusting hydraulic resistance and restoring pressure with the blister actuator.

• Smart Structures and Systems
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• v.8 no.5
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• pp.449-470
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• 2011

During the last thirty years many structural control concepts have been proposed for the reduction of the structural response caused by earthquake excitations. Their research and implementation in practice have shown that seismic control of structures has a lot of potential but also many limitations. In this paper the importance of two practical issues, time delay and saturation effect, on the performance of controlled structures, is discussed. Their influence, both separately and in interaction, on the response of structures controlled by a modified pole placement algorithm is investigated. Characteristic buildings controlled by this algorithm and subjected to dynamic loads, such as harmonic signals and actual seismic events, are analyzed for a range of levels of time delay and saturation capacity of the control devices. The response reduction surfaces for the combined influence of time delay and force saturation of the controlled buildings are obtained. Conclusions regarding the choice of the control system and the desired properties of the control devices are drawn.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.50 no.11
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• pp.563-567
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• 2001

ln this paper, the designed DVSC(Discrete Variable Structure Controller) is applied to the robust control of voltage controlled APF(Active Power Filter). The voltage controlled APF has good characteristics of reducing harmonic current and harmonic voltage simultaneously. However, voltage controlled APF with large capacitor has slow dynamic response. For improving the dynamics and robustness against to disturbances, DVSC is adopted. According to the results of experiment and simulation, it is proved that the proposed system has the performance of improving dynamic response and robustness.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.12
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• pp.1057-1065
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• 2000

A sizing of sensible and latent energy recovery system with condensing heat exchanger is important to the design of a thermally controlled facilities. The transient system simulation program TRNSYS 14.2/IISiBat has been used to evaluate the energy consumptions of a thermally controlled facilities which consist of boiler, chiller and condensing heat exchanger, The boiler and chiller are selected based on the annual peak loads and controlled to maintain the setting temperature of $14~17^{\circ}C$. Simulation shows that the amount of sensible and latent energy recovered by heat exchanger is almost 20% of total heating load.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.53 no.6
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• pp.402-408
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• 2004

This paper proposes the novel V/f control method to improve the stability of a V/f controlled induction motor drive system. The conventional V/f control method used in the proposed V/f control method is a vector-based method that is slightly different from the existing conventional V/f control method. The proposed control method uses a dynamic current compensator to improve the stability of a V/f controlled induction motor drive system. This proposed method is easy to implement and completely eliminates the motor oscillation phenomenon causing the instability of a V/f controlled induction motor drive system, especially when the system is driven near the resonant frequency in steady-state with light load. Additionally, this paper analyzes theoretically the instability of a V/f controlled induction motor drive system and shows the validity of the Proposed V/f control method through simulation and experimental results.

• Food Science and Industry
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• v.50 no.2
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• pp.27-36
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• 2017

Today, the food packaging industry has a great interest in using active packaging to fresh food product as a solution for the future to positively provide its quality, safety and shelf life. Many researches have extensively studied functional packaging strategies in recently years. Controlled release packaging (CRP) is an innovative packaging technology in the packaging polymer matrix from which can active agents are delivered in a controlled way into the product. CRP technology is well-suited for controlling release of antimicrobial compounds and antioxidants to prevent food degradation reactions such as microbial growth and lipid oxidation. Advances in CRP technology allow food packaging manufacturers to challenge the development of better functional food packaging systems. This overview examines the most recent developments and technologies of active packaging for applying the food industry. The scope of this article has mainly been focused on controlled releasing systems.