• The Journal of Information Technology
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• v.5 no.2
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• pp.47-54
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• 2002

OFDM ambient noise and entrain error that this research proposes in IEEE 802.11g, use 256-State 2/3 binary scale Convoulutional 8-PSK Modulations, FEC coding, PBCC and did speed of 12 Mbpses that belong on category of 5 GHzs Band FHSS way so that can be applied in 20 Mbpses DSSS'S generalization that is establishing Pyojunan in current IEEE embodying transmission device model who operate with the equal speed from 2.4 GHzs ISM Band important duty to DSSS way.

• Journal of Broadcast Engineering
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• v.26 no.2
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• pp.197-207
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• 2021

The emergency alert broadcast service based on cellular communications is defined as CBS. However, the CBS just supports a limited text message, which might be unavailable to foreigners, who are unfamiliar with local characters. The CBS protocol relies on a broadcast mechanism. Such a broadcast technology exhibits that the number of outage users significantly increases under poor channel conditions. In this paper, we present a supplementary service technology for 5G CBS, which considerably enhances the accessibility of foreigners and illiterate persons, and the receiver performance. For the enhanced receiver performance, the proposed supplementary service approach effectively exploits the device-based geo-targeting capability that the 5G CBS can afford to offer.

• International Journal of Precision Engineering and Manufacturing-Green Technology
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• v.5 no.5
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• pp.571-581
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• 2018

In the present study, monitoring of elliptical vibration cutting process by utilizing internal data in the ultrasonic elliptical vibration device without external sensors such as a dynamometer and displacement sensor is investigated. The internal data utilized here is the change of excitation frequency, i.e. resonant frequency of the device, voltages applied to the piezoelectric actuators composing the device, and electric currents flowing through the actuators. These internal data change automatically in the elliptical vibration control system in order to keep a constant elliptical vibration against the change of the cutting process. Correlativity between the process and the internal data is described by using a vibration model of ultrasonic elliptical vibration cutting and verified by several experiments, i.e. planing and mirror surface finishing of hardened die steel carried out with single crystalline diamond tools. As a result, it is proved that it is possible to estimate the elements of elliptical vibration cutting process, e.g. tool wear and machining load, which are important for stable cutting in such precision machining.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.5
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• pp.1-13
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• 2013

This study found fit optimum C, M, Y, K solid density and $CIEL^*a^*b^*$ value to paper & ink as well as check about printing machine state for color management in H-UV waterless off-set printing first. These values applied to GRACoL G7 calibration method. This method is one of color standard management method of printing. GRACoL G7 calibration method is possible stable tone reappearance by controlling gray balance by NPDC(Natural Printing Density Curve). Also, this study used values to make device profile as result that is gotten by application of GRACoL G7 calibration method. This profile was applied to CMS(Color Management System) of H-UV waterless off-set printing, and the result was possible by color management that correspond in printing quality standard of ISO 12647-2 and GRACol 2006 specifications.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.05a
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• pp.85-87
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• 2018

Motivating by two promising technique of 5G, namely D2D and Edge computing, and the above mentioned problem of the current joint studies, We believe that more study is needed on the benefits of joining these two techniques in a single framework by more precisely taking into account the energy needed to computation, sending data, receiving data and as a result achieving more realistic energy efficiency in 5G cellular networks.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.5
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• pp.794-803
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• 1987

In this paper, the SPICE 2.G6 JFET subroutine and other related subroutines are modified for circuit simulation of GaAs MESFET IC's. The hyperbolic tangent model is used for the drain current-voltage characteristics of GaAs MESFET's and derived channel-conductance and drain-conductance model from the above current model are implemented into small-signal model of GaAs MESFET's. And, device capacitance model which consider after-pinch-off state are modified, and device charge model for SPICE 2G.6 are proposed. The result of modification is shown to be suitable for GaAs circuit simulator, showing good agreement with experimetal results. Forthermore the DC convergence of this paper is better than that of SPICE 2.G JFET subroutine. GaAs MESFET model in this paper is applied for both depletion mode GaAs MESFET and enhancement-mode GaAs MESFET without difficulty.

• ETRI Journal
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• v.39 no.6
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• pp.874-879
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• 2017

This paper challenges the fabrication of a thin film energy storage device on a flexible polymer substrate specifically by replacing most commonly used metal foil current collectors with coated current collectors. Mass-manufacturable spray-coating technology enables the fabrication of two different half-cell electric double layer capacitors (EDLC) with a spray-coated silver paste current collector and a Ni foil current collector. The larger specific capacitances of the half-cell EDLC with the spray-coated silver current collector are obtained as 103.86 F/g and 76.8 F/g for scan rates of 10 mV/s and 500 mV/s, respectively. Further, even though the half-cell EDLC with the spray-coated current collector is heavier than that with the Ni foil current collector, smaller Warburg impedance and contact resistance are characterized from Nyquist plots. For the applied voltages ranging from -0.5 V to 0.5 V, the spray-coated thin film energy storage device exhibits a better performance.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.5
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• pp.568-575
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• 2011

In this paper, we propose a small broadband antenna for mobile device. The proposed antenna consists of a printed rectangular monopole antenna and a parastic element connected to ground using narrow meander line and it is designed on a FR-4 substrate that has a thickness of 0.8 mm and a dielectric constant of 4.4. The FR-4 substrate's size is 50 mm${\times}$90 mm comparable to the real mobile device. The fabricated antenna's size is 12.5 mm${\times}$10.5 mm${\times}$0.8 mm and the measurement shows -10 dB return loss bandwidth of 2,200~6,000 MHz and gains of 2.86~4.01 dBi. Accordingly, the proposed antenna can support mobile device for WiBro(2,300~2,380 MHz), WLAN(IEEE 802.11b/g/n: 2,400~2,480 MHz, IEEE 802.11a: 5,150~5,825 MHz), and mobile WiMAX(IEEE 802.16e : 2,500~2,690 MHz, 3,400~3,600 MHz) service bands.

• JSTS:Journal of Semiconductor Technology and Science
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• v.7 no.1
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• pp.51-55
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• 2007

This paper investigates the subthreshold behavior of Fin Field Effect Transistor (FinFET). The FinFET is considered to be an alternate MOSFET structure for the deep sub-micron regime, having excellent device characteristics. As the channel length decreases, the study of subthreshold behavior of the device becomes critically important for successful design and implementation of digital circuits. An accurate analysis of subthreshold behavior of FinFET was done by simulating the device in a 3D process and device simulator, Taurus. The subthreshold behavior of FinFET, was measured using a parameter called S-factor which was obtained from the $In(I_{DS})\;-\;V_{GS}$ characteristics. The value of S-factor of devices of various fin dimensions with channel length $L_g$ in the range of 20 nm - 50 nm and with the fin width $T_{fin}$ in the range of 10 nm - 40 nm was calculated. It was observed that for devices with longer channel lengths, the value of S-factor was close to the ideal value of 60 m V/dec. The S-factor increases exponentially for channel lengths, $L_g\;<\;1.5\;T_{fin}$. Further, for a constant $L_g$, the S factor was observed to increase with $T_{fin}$. An empirical relationship between S, $L_g$ and $T_{fin}$ was developed based on the simulation results, which could be used as a rule of thumb for determining the S-factor of devices.

• Journal of Pharmaceutical Investigation
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• v.36 no.4
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• pp.263-269
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• 2006

Deficiencies in the early ADMET(absorption, distribution, metabolism, elimination and toxicity) information on drug candidate extract a significant economic penalty on pharmaceutical firms. Microscale cell culture analogue-microscale gastrointestinal(${\mu}CCA-{\mu}GI$) device using Caco 2, L2 and HEp G2/C3A cells, which mimic metabolic process after absorption occurring in humans was used to investigate the toxicity of the model chemical, acetaminophen(AAP). The toxicity of acetaminophen determined after induction of CYP 1A1/2 in Caco 2 cells was not significant. In a coculture system, although no significant reduction in viability of HEp G2/C3A and L2 cells was found, approximately 5 fold increase in the CYP 1A1/2 activity was observed. These results appear to be related to organ-organ interaction. The oral administration of a drug requires addition of the absorption process through small intestine to the current ${\mu}CCA$ device. Therefore, a perfusion coculture system was employed for the evaluation of the absolution across the small intestine and resulting toxicity in the liver and lung. This system give comprehensive and physiologic information on oral uptake and resulting toxicity as in the body. The current ${\mu}CCA$ device can be used to demonstrate the toxic effect due to organ to organ interaction after oral administration,