• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.7
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• pp.1214-1229
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• 2011

Power control is a key technique in spectrum underlay cognitive network to guarantee the interference temperature limit of the primary users (PUs) and the quality of service of the secondary users (SUs). In this paper, a robust power control scheme via link gain pricing with $H_{\infty}$ estimator is proposed. The scheme guarantees the interference temperature of the PUs through operating in the network-centric manner, and keeps the fairness between the SUs through link gain pricing. Furthermore, the $H_{\infty}$ filter is also used in the proposed scheme to estimate the channel variation, and thus the power control scheme is robust to the severe channel fading. Plenty of simulations are taken, and prove its superior robust performance against the channel fading, and its effectiveness in guaranteeing the interference temperature limit of the PUs.

• Journal of Power Electronics
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• v.9 no.5
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• pp.726-735
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• 2009

This paper presents a Bidirectional High-Frequency Link (BHFL) inverter that utilizes the Deadbeat controller. The main features of this topology are the reduced size of the inverter and fewer power switches. On the secondary side of the transformer, the active rectifier employs only two power switches, thus reducing switching losses. Using this configuration, the inverter is capable of carrying a bidirectional power flow. The inverter is controlled by a Deadbeat controller, which consists of the inner current loop, outer voltage loop and a feedforward controller. Additional disturbance decoupling networks are employed to improve the system's robustness towards load variations. A 1-kVA prototype inverter has been constructed and the Deadbeat control algorithm is experimentally verified. The experimental results show that the inverter has high efficiency (91%) with low steady state output voltage total harmonics distortion (1.5%).

• Proceedings of the KIPE Conference
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• 2004.07b
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• pp.795-798
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• 2004

This paper describes a control technique for a high frequency (HF) link current-fed inverter with a single power conversion stage. The switching and control techniques for the primary full-bridge inverter and secondary cycloconverter are presented for generating a sinusoidal output voltage. The simulation and experimental results are provided to show the validity of the proposed control technique.

• Proceedings of the KIPE Conference
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• 2004.11a
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• pp.124-126
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• 2004

This paper describes a boost converter cascaded high frequency link direct do-ac converter suitable for fuel cell power sources. A new multi-loop control for a boost converter to reduce the low frequency input current harmonics drawn from fuel cell is proposed. A new PWM technique for the cycloconverter at the secondary to reject the low order harmonics in the output voltages is presented in detail.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.11a
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• pp.245-249
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• 2005

This paper describes a boost converter cascaded high frequency link direct dc-ac converter suitable for fuel cell power sources. A new multi-loop control for a boost converter to reduce the low frequency input current harmonics drawn from fuel cell is proposed. A new PWM technique for the cycloconverter at the secondary to reject the low order harmonics in the output voltages is presented in detail.

• Proceedings of the KIPE Conference
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• 2010.11a
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• pp.30-31
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• 2010

Filament power supply (FPS) for neutral beam injection (NBI) consists of an insulation type is a device that heats the interior of Tokamak. The input/output specifications of FPS are 3-phase AC 200[Vpeak] and DC16V/300A respectively. A conventional FPS is composed of a 3-phase diode rectifier with DC-link, a H-bridge DC/DC converter, a high frequency transformer, a secondary rectifier and a LC-filter. In this paper, to improve the efficiency of PSFB DC/DC converter it is substituted IGBT devices instead of diode rectifier in secondary side. The proposed method is verified by computer simulation and experiment result.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.435-436
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• 2001

In sand beaches the benthic macrofauna feeding on primary food sources such as detritus and phytoplankton and being prey in turn for top predators such as fishes occupies a key position in the center of food chains. Amphipods are the most productive bentho-pelagic animals (Barnard, 1963) and are commonly consumed by fishes and larger crustaceans (Vetter, 1995). Consequently, amphipods play an important role in energy flow as a trophic link from primary producers to higher consumers(Chiaravalle et al., 1997).

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.1
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• pp.105-110
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• 2015

In cognitive radio networks, when the signal-to-noise ratio (SNR) of the link between a primary transmitter and receiver is sufficiently high, the primary transmission does not frequently demand cooperation because direct transmission of the primary communication is usually successful. Therefore, there are few opportunities for a secondary transmitter to cooperate with the primary user system in exchange for an opportunity to share the spectrum. This article proposes a scheme in which the secondary system can deliberately degrade the SNR of the primary transmission, making it so that the primary system needs cooperation from the secondary nodes, and thereby increases opportunities for spectrum sharing.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.2
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• pp.437-444
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• 2009

There are many activities that open source software may using at several areas from the government and international organization such as the UN. And Korea enforces the open source software demonstration activities with different meaning link. It is an evaluation field whether or not using the open source software in information projects. But the public information and the education against the open source software are insufficient in the secondary school students who are be latent open source software users. In this paper, We present an examination and analysis of the open source software recognition of the secondary school students in Korea. And We suggest education methods that can use the open source software in the information subject of the revised 7th national education curriculum.

• Journal of Microbiology and Biotechnology
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• v.23 no.4
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• pp.527-533
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• 2013

Polyclonal antibodies labeled with a tracer have been commonly used as secondary antibodies in immunochemical assays to quantify the concentration of antibody-antigen complexes. The majority of these antibodies conjugated with a tracer are commercially available, with the exception of few untouched targets. This study focused on the production and application of mouse anti-quail IgY as an intermediate antibody to link between quail egg yolk IgY and goat anti-mouse IgG-HRP as primary and secondary antibodies, respectively. Subsequently, the produced mouse anti-quail IgY was labeled with horseradish peroxidase (HRP) and its efficiency on enzyme linked immunosorbent assay (ELISA) was compared with that of commercial rabbit anti-chicken IgY-HRP. As an intermediate antibody, mouse anti-quail IgY was successfully produced with good affinity and sensitivity (1:10,000) to the primary and secondary antibodies. Subsequently, mouse anti-quail IgY was effectively conjugated with HRP enzyme, resulting in a secondary antibody with good sensitivity (1:10,000) to quail anti-V. parahaemolyticus and V. vulnificus IgY. The detection limit was $10^5$ CFU/ml for both V. parahaemolyticus and V. vulnificus. The efficiency of the produced conjugate to detect quail IgY on ELISA was comparable to that of the commercial rabbit anti-chicken IgY-HRP, and hence the produced and labeled mouse anti-quail IgY-HRP can be used as a secondary antibody to detect any antibody produced in quail.