• Proceedings of the KIEE Conference
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• 1998.11b
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• pp.624-626
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• 1998

Adaptive channel equalization accomplished without resorting to a training sequence is known as blind equalization. In this paper, we present a auto-switching blind, equalization for 8-VSB HDTV receiver. The scheme operate in two mode : blind equalization mode and decision-directed equalization mode. This proposed scheme changes from the blind equalization mode at high error levels to the decision-directed equalization mode at lower error levels smoothly and automatically. Manual switch from the blind equalization mode to the decision-directed mode is not necessary.

• Journal of Integrative Natural Science
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• v.11 no.1
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• pp.39-43
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• 2018

Poly(hydroxyethyl methacrylate)-based hydrogels were surface-functionalized with spiropyran (SP) derivatives to obtain photochromic contact lenses. The contact lens reversibly changes from colorless to purple as response to UV light since colorless ring-closed SP state converts to purple ring-opened merocyanine (MC) state under UV light irradiation. The purple contact lens emits red light at 640 nm. Importantly, the presence of SP segments did not significantly affect the equilibrium water content (EWC) of the lens. SP-functionalized hydrogel lenses may find potential applications in developing light-adaptive ophthalmic materials.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.54 no.8
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• pp.395-401
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• 2005

This paper presents Hybrid PI(HBPI) controller of induction motor drive using fuzzy control. In general, PI controllers used in computer numerically controlled machines process fixed gain. They may perform well under some operating conditions, but not all. To increase the robustness of fixed gain PI controller, HBPI controller proposes a new method based self tuning PI controller. HBPI controller is developed to minimize overshoot and settling time following sudden parameter changes such as speed, load torque, inertia, rotor resistance and self inductance. The results on a speed controller of induction motor are presented to show the effectiveness of the proposed gam tuner. And this controller is better than the fixed gains one in terms of robustness, even under great variations of operating conditions and load disturbance.

• Journal of The Korea Institute of Healthcare Architecture
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• v.15 no.1
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• pp.53-62
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• 2009

Healthcare facilities undergo substantial renovation and remodeling to accommodate changing technologies and regulatory requirements, thereby generating significant quantities of construction-related wastes, and subjecting building occupants to noise, dust, and other health impacting disruptions associated with construction. By designing flexible, adaptive, generic spaces, buildings can better respond to changes imposed by architectural composition of interpersonal and community space of hospital ward with minimum needs renovation and remodeling. This study focuses on the design principles of enhancing flexibility in architectural composition of interpersonal and community space of hospital ward. The purpose of this study is to provide fundamental data for designing interpersonal and community space of hospital ward through ecological flexible design principles with case on interpersonal and community space of hospital ward.

• 한국IT서비스학회:학술대회논문집
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• 2005.11a
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• pp.356-365
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• 2005

Since their first inception a few decades ago, software components have received much attention mainly due to their alleged benefits of quality and productivity improvement. Despite this, it is yet to be agreed upon what and how components should be designed. This paper aimed to bridge the gap by proposing a collaborative process where the voice of the customer is captured and documented by employing the event and entity models. These requirement elements (WHAT) are cross-tabulated in three relation matrices in accordance with the weights provided by the business users. The requirements are fed into the algorithm invented by the authors to optimize the component grouping (HOW). This collaborative process has been successfully validated at an enterprise wide software development project. The process was effective to help the users more actively involved in the design of the system and made the whole process faster and more adaptive to the changes.

• Journal of Power Electronics
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• v.15 no.1
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• pp.235-245
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• 2015

This paper proposes a reactive current assignment and control strategy for a doubly-fed induction generator (DFIG) based wind-turbine generation system under generic grid voltage sag or swell conditions. The system's active and reactive power constrains during grid faults are investigated with both the grid- and rotor-side convertors (GSC and RSC) maximum ampere limits considered. To meet the latest grid codes, especially the low- and high-voltage ride-through (LVRT and HVRT) requirements, an adaptive reactive current control scheme is investigated. In addition, a torque-oscillation suppression technique is designed to reduce the mechanism stress on turbine systems caused by intensive voltage variations. Simulation and experiment studies demonstrate the feasibility and effectiveness of the proposed control scheme to enhance the fault ride-through (FRT) capability of DFIG-based wind turbines during violent changes in grid voltage.

• Journal of Information Technology Services
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• v.5 no.1
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• pp.177-190
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• 2006

Since their first inception a few decades ago, software components have received much attention mainly due to their alleged benefits of quality and productivity improvement. Despite this, it is yet to be agreed upon what and how components should be designed. This paper aims to bridge the gap by proposing a collaborative process where the voice of the customer is captured and documented by employing the event and entity models. These requirement elements (WHAT) are cross-tabulated in three relation matrices in accordance with the weights provided by the business users. The requirements are fed into the algorithm invented by the authors to optimize the component grouping (HOW). This collaborative process has been successfully validated at an enterprise wide software development project. The process was effective to help the users more actively involved in the design of the system and made the whole process faster and more adaptive to the changes.

• Annual Conference of KIPS
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• 2015.04a
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• pp.212-213
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• 2015

Data aggregation is a fundamental problem in wireless sensor networks that has attracted great attention in recent years. On constructing a robust algorithm for minimizing data aggregation delay in wireless sensor networks, we consider limited transmission range sensors and approximate the minimum-delay data aggregation tree which can only be built in networks of unlimited transmission range sensors. The paper proposes an adaptive method that can be applied to maintain the network structure in case of a sensor node fails. The data aggregation tree built by the proposed scheme is therefore self-healing and robust. Intensive simulations are carried out and the results show that the scheme could adapt well to network topology changes compared with other approaches.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.41.2-41
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• 2001

A torque transmission system, which is composed of several gears and couplings, is flexible. Therefore, the torsion vibration occurs when the motor speed abruptly changes. Consequently, for Accuracy characteristic response of motor, we must suppressed vibration. Therefore, vibration suppression is very important motor control. To vibration suppression, various control method have been proposed. Specially, one method of vibration suppression used disturbance observer filter. This method is torsion torque passing disturbance observer filter. By feedback of the estimated torsion torque, the vibration can be suppressed The coefficient diagram method is used to design the filter and proportional controller.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.3
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• pp.1464-1480
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• 2019

Robust tracking of infrared (IR) pedestrian targets with various backgrounds, e.g. appearance changes, illumination variations, and background disturbances, is a great challenge in the infrared image processing field. In the paper, we address a new tracking method for IR pedestrian targets via multi-feature local sparse representation (SR), which consists of three important modules. In the first module, a multi-feature local SR model is constructed. Considering the characterization of infrared pedestrian targets, the gray and edge features are first extracted from all target templates, and then fused into the model learning process. In the second module, an effective tracker is proposed via the learned model. To improve the computational efficiency, a sliding window mechanism with multiple scales is first used to scan the current frame to sample the target candidates. Then, the candidates are recognized via sparse reconstruction residual analysis. In the third module, an adaptive dictionary update approach is designed to further improve the tracking performance. The results demonstrate that our method outperforms several classical methods for infrared pedestrian tracking.