• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.7-7
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• 2009

In this paper, we investigated the dependence of HCI (Hot Carrier Immunity) degradation and device performance on channel orientation in sub-micron PMOSFET. Although device performance ($I_{D.sat}$ vs. $I_{Off}$) was improved as the transistor angle increased HC immunity was degraded. Therefore, consideration of reliability characteristics as well as dc device performance is highly necessary in channel stress engineering of next generation CMOSFETs.

• Journal of the Optical Society of Korea
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• v.18 no.6
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• pp.788-792
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• 2014

It has been a critical issue to reduce the size of spectrometers in many fields such as on-chip chemical and biological sensing. The proposed plasmonic channel-waveguide with a sub-micrometer width has a cutoff frequency which enables us to control wavelength dependent propagation properties. We focused on the capability of the waveguide for spectral-to-spatial mapping when the waveguide width changes gradually. In this paper, we propose a plasmonic tapered channel-waveguide structure as a compact spectrometer with a physical size of $0.24{\times}2.0{\times}0.20{\mu}m^3$. The scattering point just above the tapered waveguide moves linearly depending on the wavelength of the injecting light. The spectral-to-spatial mapping can be improved by increasing the tapered length.

• Proceedings of the Korea Contents Association Conference
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• 2005.11a
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• pp.596-600
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• 2005

In High-speed Portable Internet system to improve performance of whole system, adaptive modulation and coding technology is used, this technology changes modulation and encoding techniques depending on wireless channel environment. Modulation technology that is used in High-speed Portable Internet system is BPSK, QPSK, 16QAMs and 64QAMs. If terminal is distant from base station transceiver system, BPSK or QPSK technology Is used and 16QAMs or 64QAM technology is used if is near in the base station transceiver system. In this paper, number of sub-channel in each modulation technology minimized total transmitting number of PDU is analyzed for efficient radio resources usage. For this, simulation is conducted and the results are presented at High-speed Portable Internet system environments.

• Journal of Korea Society of Digital Industry and Information Management
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• v.13 no.3
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• pp.75-81
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• 2017

This paper estimate a desired signal in a correlation wireless communication. The transmitted signal is mixed with the information signal, interference, and noise in wireless channel, and it is incident on the receiver. In this paper, we apply MUSIC algorithm and sub-array method to recover the total rank of the correlation matrix in order to estimation a desired signal among receiving signals. Through simulation, we analyze to compare the proposed method with the classical MUSIC algorithm. As a result of the simulation, the proposed method improved the resolution about 10degrees compared to the conventional MUSIC algorithm. We prove the superiority of the proposed method for the desired signal estimation in correlation channel.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.611-627
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• 2017

For enhancing the coverage of wireless networks and increasing the spectrum efficiency, small cell networks (SCNs) are considered to be one of the most prospective schemes. Most of the existing literature on resource allocation among non-cooperative small cell base stations (SBSs) has widely drawn close attention and there are only a small number of the cooperative ideas in SCNs. Based on the motivation, we further investigate the cooperative approach, which is formulated as a coalition formation game with power control algorithm (CFG-PC). First, we formulate the downlink sub-channel resource allocation problem in an SCN as a coalition formation game. Pareto order and utilitarian order are applied to form coalitions respectively. Second, to achieve more availability and efficiency power assignment, we expand and solve the power control using particle swarm optimization (PSO). Finally, with our proposed algorithm, each SBS can cooperatively work and eventually converge to a stable SBS partition. As far as the transmit rate of per SBS and the system rate are concerned respectively, simulation results indicate that our proposed CFG-PC has a significant advantage, relative to a classical coalition formation algorithm and the non-cooperative case.

• Membrane Journal
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• v.31 no.6
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• pp.404-416
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• 2021

In this study, a mixed matrix membrane was prepared by varying the contents of GO and PEI-GO synthesized in PEBAX2533, and the permeation characteristics of N₂ and CO₂ were studied. The N₂ and CO₂ permeability of the PEBAX/GO mixed membrane decreased as the GO content increased, and showed the highest CO₂/N₂ selectivity of 58.9 at GO 0.3 wt%. For the PEBAX/PEI-GO mixed membrane, the N₂ permeability decreased as the PEI-GO content increased, and the CO₂ permeability showed a different trend according to the PEI-GO content. Overall, the CO₂/N₂ selectivity was higher than that of the PEBAX/GO mixed membrane. In particular, PEI-GO 0.3 wt% showed the highest CO₂/N₂ selectivity of 73.5 among the mixed membranes, and a positive result was obtained as it was located above the Robeson upper bound. This is believed to be due to the molecular sieving channel effect resulting from the original GO structure, the functional groups present in the structure of GO having affinity for CO₂, and the effect of amine bound to PEI by modifying GO into PEI.

• JSTS:Journal of Semiconductor Technology and Science
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• v.8 no.2
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• pp.170-177
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• 2008

In the present work a methodology to minimize short channel effects (SCEs) by modulating the effective channel length is proposed to design 25 nm single and double gate-source/drain underlap MOSFETs. The analysis is based on the evaluation of the ratio of effective channel length to natural/ characteristic length. Our results show that for this ratio to be greater than 2, steeper source/drain doping gradients along with wider source/drain roll-off widths will be required for both devices. In order to enhance short channel immunity, the ratio of source/drain roll-off width to lateral straggle should be greater than 2 for a wide range of source/drain doping gradients.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.5
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• pp.549-553
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• 1998

Using the planar lipid bilayer method, we investigated the effect of d-tubocurarine (dTC) on the extracellular side of large-conductance $Ca^{2+}-activated\;K^+$ channel from rat brain. When the initial open probability (Po) of the channel was relatively high, dTC decreased channel activity in a concentration dependent manner. In contrast, when the initial Po was lower, sub-micro molar dTC increased channel activity by destabilizing the closed states of the channel. Further addition of dTC up to micro molar range decreased channel activity. This dual effect of dTC implicates that there exist at least two different binding sites for dTC.

• Journal of information and communication convergence engineering
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• v.8 no.4
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• pp.449-452
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• 2010

We have analyzed channel doping and dimensions(channel length, width and thickness) for the optimum subthreshold characteristics of DG(Double Gate) MOSFET based on the model of MicroTec 4.0. Since the DGMOSFET is the candidate device to shrink short channel effects, the determination of design rule for DGMOSFET is very important to develop sub-100nm devices for high speed and low power consumption. As device size scaled down, the controllability of dimensions and oxide thickness is very low. We have analyzed the short channel effects for the variation of channel dimensions, and found the design conditions of DGMOSFET having the optimum subthreshold characteristics for digital applications.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.3
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• pp.313-321
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• 2009

This paper describes the downlink design of a transportable small-sized KOMPSAT ground station using sub-carrier signal. Based on the analysis of the transmission modes of satellite real-time telemetry and range measurement signals, the downlink channel design of KOMPSAT ground station using sub-carrier signal was processed. By considering the threshold signal-to-noise ratio of real-time 2 kbps telemetry signal and the required signal-to-noise ratio for satellite range measurement, the small-sized KOMPSAT downlink channel with G/T value of 6.5 dB/K was designed. The real G/T of implemented ground station was proven to be 6.62 dB/K when measured using the Sun. Moreover, through interface test with KOMPSAT, the ground station has shown the required link performance for real-time telemetry acquisition using sub-carrier and was consequently evaluated to be adequate for a transportable small-sized KOMPSAT ground station.