• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.247-249
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• 2008

There are many types of grid-connected inverter controllers; Synchronous Reference Frame (SRF)-based controller is the most popular methods. SRF-based controller is capable for reducing both of zero-steady state error and phase delay. However, SRF-based controller has a complex algorithm to apply in real application such as digital processor. Resonant controller is also reduced zero-steady state error, but its transfer function has a high order. In this paper, a simple proportional control is applied for grid connected inverter with LCL filter. LCL filter is a third order system. Applying a simple proportional controller is not increased the order of closed loop transfer function. By this technique, the single phase model is easily obtained. To reduce steady state error, proportional gain is set as high as possible, but it may produce instability. To compromise between a minimum steady state error and stability, the single phase model is evaluate through Root Locus and Bode diagram. PSIM simulation is used to verify the analysis.

• The Journal of the Korean dental association
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• v.49 no.12
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• pp.739-748
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• 2011

Patients with severe mental challenges are often subjected to extensive dental problems. Their impaired communication and lack of cooperation unable to receive timely dental treatments, which deteriorates their adverse oral conditions. In spite of a limited time frame, well-planned comprehensive treatments can be delivered in an one-day operation setting under general anesthesia. This multidisciplinary treatment regimen primarily comprises of single-visit endodontics, direct bonded restoration, periodontal treatment, and surgical extraction. Further, one or two additional visits for prosthetic procedures are able to accomplish functional reestablishment and esthetic enhancement. This article discusses on clinical managements for severely mentally challenged patients under a single-day operation.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.5
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• pp.155-164
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• 1996

The architecture of a programmable video codec IC is described that employs multiple vector processors in a single chip. The vector processors operate in parallel and communicate with one another through on-chip shared memories. A single scalar control processor schedules each vector processor independently to achieve real-tiem video coding with special vector instructions. With programmable interconnection buses, the proposed architecture performs multi-processing of tasks and data in video coding. Therefore, it can provide good parallelism as well as good programmability. especially, it can operate multithread video coding, which processes several independent image sequences simultaneously. We explain its scheduling, multithred video coding, and vector processor architectures. We implemented a prototype video codec with a 0.8um CMOS cell-based technology for the multi-standard videophone. This codec can execute video encoding and decoding simultaneously for the QCIF image at a frame rate of 30Hz.

• The Plant Pathology Journal
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• v.16 no.2
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• pp.105-109
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• 2000

The Pi-b is the rice gene conferring race specific resistance to the blast fungus Magnaporthe grisea race having a corresponding avirulence gene, AVR-Pi-b. All resistant cultivars have two copies of the Pi-b gene, but susceptible cultivars have a single copy of the gene. About 1 Kbp insertion sequence was detected in the open reading frame of the Pi-b gene from the susceptible cv. Nipponbare. The nature of insertion sequence was identified as a solo long terminal repeat (LTR) of new rice Tyl-copia-like retrotransposon. LTR was widely distributed in the rice genome. Various types of different patterns of restriction fragment length polymorphism of LTR were detected in indica cultivars, whereas a single type was detected from japonica cultivars. The insertion of LTR sequence in the Pi-b gene in the susceptible cultivar suggested that retrotransposon-mediated insertional mutation might played an important role in the resistance breakdown as well as evolution of resistance genes in rice.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.3
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• pp.125-132
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• 2011

Is very simple in tension work of screen mesh for effective printing if worker uses screen mesh of player who desire at screen print process. General method is methods that use mesh of player who want on screen frame as screen plate because tensioned. The single layer screen plate was made from one sheet screen mesh and the double layer screen plate was made from two sheets screen mesh overlapped. The thickness of sensitive emulsion applied to double layer screen plate is more thicker than two time s of thickness of emulsion applied to single layer screen plate. It seems that the sensitive emulsion inserted between an upper layer and a lower layer of double layer screen mesh.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.283-289
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• 1998

In the latticed domes which is a set of space frame, buckling is derived if the external force reaches a limitation by the lightness of the material and the minimization of the member section area. these are concerned with a geometric shape, network pattern, the number of layer, and so on. Most of all, the number of layer of the lattice dome is a important factor from the viewpoint of initial and structure design. Therefore this study compared buckling characteristics of single-layer with double-layer latticed domes and investigated the relativity of buckling-stress-ratio and member-density-ratio according to rise ratio to improve that designers could extend the range of .design selection

• Current Optics and Photonics
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• v.1 no.4
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• pp.289-294
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• 2017

A high-performance time-division multiplexing (TDM) -based multiuser (MU) multiple-input multipleoutput (MIMO) system for efficient indoor visible-light communication (VLC) is presented. In this work, a MIMO technique based on RGB light-emitting diodes (LEDs) with selection combining (SC) is utilized for data transmission. That is, the proposed scheme employs RGB LEDs for parallel transmission of user data and transmits MU data in predefined slots of a time frame with a simple and efficient design, to schedule the transmission times for multiple users. Simulation results demonstrate that the proposed scheme offers an approximately 6 dB gain in signal-to-noise ratio (SNR) at a bit error rate (BER) of $3{\times}10^{-5}$, as compared to conventional MU single-input single-output (SISO) systems. Moreover, a data rate of 66.7 Mbps/user at a BER of $10^{-3}$ is achieved for 10 users in indoor VLC environments.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.11
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• pp.50-57
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• 2011

This paper proposes a boost type single-phase inverter system to compensate the voltage sag appeared on source side. The proposed system is composed of a boost converter, a PWM inverter, and a bypass diode. If the voltage sag has appeared in input voltage, the boost converter would be operated to compensate it in the proposed system. The boost converter would not be operated when the magnitude of input voltage is more than 0.9 pu. The output voltage is kept constant by a direct-quadrature frame controller in the inverter. A 300 W class boost type inverter system was simulated, and the validity of the proposed system was verified by carrying out experiments.

• Proceedings of the KIPE Conference
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• 2013.07a
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• pp.1-2
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• 2013

In this paper, we inject input currents having $3^{rd}$ harmonic to reduce the capacitance of DC link capacitors in single-phase converters. If the input current with third harmonic is injected, the required capacitance can be reduced by minimizing the difference between the input and output power. To control the input current, instead of PI control done in rotating frame, PR controller is used with the proposed separate current control method for fundamental and $3^{rd}$ harmonic components. The validity of the proposed method has been demonstrated by simulation results.

• Steel and Composite Structures
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• v.5 no.5
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• pp.345-358
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• 2005

The response of single story buildings and other case studies are investigated to observe trends in response and to develop a better understanding of the impact of some design parameters on the seismic response of CBF. While it is recognized that many parameters have an influence on the behavior of braced frames, the focus of this study is mostly on quantifying energy dissipation in compression and its effectiveness on seismic performance. Based on dynamic analyses of single story braced frame and case studies, it is found that a bracing member designed with bigger R and larger KL/r results in lower normalized cumulative energy, i.e., cumulative compressive energy normalized by the corresponding tensile energy (${\sum}E_C/E_T$), in both cases.