• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2A
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• pp.186-195
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• 2010

For the fast target base station channel decision in WiMAX networks, fast group scanning scheme was suggested, in which mobile stations in proximity of each other form a group and scan the candidate channels dispersively. However, the previous group scanning scheme does not consider the different QoS requirements of each MS in a group. In this paper we propose the enhanced group scanning scheme, so-called QoS-aware group scan scheduling scheme, that makes mobile stations in a group scan the candidate channels without deteriorating the QoS requirements. We introduce the QoS-aware channel scanning concept of a individual mobile station and show the different scanning latencies due to the different QoS requirements. With the help of the efficient channel allocation by the serving BS, in the proposed scanning scheme, a mobile station with relatively higher QoS in a group scans less amount of candidate channels than the others with relatively lower QoS, while the mobile stations in a group still guarantees the fast target base station decision. The performance results show that our proposed scanning scheme results in the fast target base station decision while considering the QoS requirements of each MS.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.99-103
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• 2013

The present communication deals with the Pharmacophore modeling, 3D QSAR and docking analysis on series of Pyrimidine derivatives as potential calcium channel blockers. The computational studies showed hydrogen bond donor, hydrogen bond acceptor, and hydrophobic group are important features for calcium channel blocking activity. These studies showed that Pyrimidine scaffold can be utilized for designing of novel calcium channels blockers for CVS disorders.

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.22-23
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• 1999

Voltage-gated $K^{＋}$ channels represent the most complex group of ion channel genes expressed in cardiovascular system. The human Kv1.5 channel (hKv1.5) represents the $I_{Kur}$ repolarizing current in atrial myocytes. The hKv1.5 channel is functionally modulated by the Kv$\beta$1.3 subunit, which converts it from a delayed rectifier to a channel with rapid inactivation and enhanced voltage sensitivity.(omitted)d)

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.6A
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• pp.563-574
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• 2006

This paper implements SCM(Spatial Channel Model), a kind of ray-tracing method which has characteristics similar to realistic wave propagation environments, for link-level performance analysis of OFDM(Orthogonal Frequency Division Multiplexing) based multiple antenna systems. The SCM is proposed by 3GPP & 3GPP2 Spatial Channel AHG(Ad-hoc Group) for system-level performance validation. In this paper, we modify the system level parameters and channel coefficient of SCM to compare the link-level performances of OFDM based multiple antenna systems. Through computer simulations, we manifest the implemented SCM channel characteristics. We analyze a realistic link-level performance of OFDM based conventional MIMO(Multiple Input Multiple Output) system and smart antenna system in the implemented channel. We also include the link-level performance of OFDM based multiple antenna systems in I-METRA(Intelligent Multi Element Transmit and Receive Antenna) and independent channel environments with the same system parameters. We suggest appropriate multiple antenna system in the given environment by comparing the link-level performance in the spatial channels that have different channel correlation values.

• The Journal of the Korea Contents Association
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• v.21 no.6
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• pp.155-164
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• 2021

The purpose of this study investigates how the audience evaluation on independency of broadcasting and news credibility of KBS and MBC affect their channel brand equity(cognition, image, loyalty, and quality). The results indicate that the audience evaluation on news credibility of KBS and MBC has stronger influence on channel brand equity than the one of independency of broadcasting. On ages, the older generation group has more positive perception on channel image and loyalty of KBS than the college student group and the college student group has more positive perception on channel cognition and quality of MBC than the older generation group. On political traits, the politically conservative groups of both KBS and MBC have more positive perception on independency of broadcasting, news credibility, and channel brand equity than the other groups. Consequently, public broadcasting systems should improve the credibility of news for securing independency of broadcasting. These systems make audience change their perception toward public broadcasting as recovering integrity of news and improving professionalism of news. Public broadcasting systems should conduct a further research to improve the management of channel brand equity by studying audiences' age and political traits.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1269-1271
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• 2008

We find some array mura are caused by S/D bridge or channel open in 4 mask process. The gray tone PR thickness non-uniformity is the main reason of these defects. By the adjustment of exposure and dry etch parameters, S/D bridge and channel open ratio drops by 10.87%.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.5
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• pp.1292-1295
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• 2005

Effects of the Seokchangpo-Wonji-Tang on recovery from disorder of stomach, liver and mental-faculty in alcoholism were studied using male Sprague-Dawley rats. The rats were assigned into 4 groups; normal, control and Seokchangpo-Wonji-Tang(SWT) group. Control group administered ethanol(25 v/v %) at a dose 3g/kg, while SWT group administered 50mg/kg of SWT 30min before treating same dose of ethanol as control group for 10 days, orally. The gastric ulceration and also GOT and GPT activities in rats were checked, and all groups were subjected to trials of straight channel on the 1st day and to those of multiple T-maze during the following 3 days. The gastric ulceration, GOT and GPT activities were increased in control group, but decreased in SWT group significantly. The time required in normal group for the straight channel of the 2nd and 3rd trials was significantly shorter than that of the 1 st, while the control group showed no significance. In the time required for the multiple T-maze trials, the control group showed no significance. But in the straight or T-maze trials, the SWT group showed significant decrease in the time required against the control group.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.8
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• pp.775-780
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• 2004

This paper describes the realization of the Ka-band group-delay equalized filter desisted with the help of a new hybrid method of Simulated Annealing(SA) and Conjugate Gradient(CG), to be employed by the multi-channel Input Multiplexer for a satellite use, each channel of which comprises a channel filter and a group-delay equalizer. The SA and CG find circuit parameters of an 8th order elliptic function filter and a 2-pole equalizer, respectively. Measurement results demonstrate that the performances of the designed component meet the specifications, and validate the design methods.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.9
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• pp.4223-4239
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• 2016

In this paper, we consider an amplify-and-forward (AF) full-duplex relay network (FDRN) using simultaneous wireless information and power transfer, where a battery-free relay node harvests energy from the received radio frequency (RF) signals from a source node and uses the harvested energy to forward the source information to destination node. The time-switching relaying (TSR) protocol is studied, with the assumption that the channel state information (CSI) at the relay node is imperfect. We deliver a rigorous analysis of the outage probability of the proposed system. Based on the outage probability expressions, the optimal time switching factor are obtained via the numerical search method. The simulation and numerical results provide practical insights into the effect of various system parameters, such as the time switching factor, the noise power, the energy harvesting efficiency, and the channel estimation error on the performance of this network. It is also observed that for the imperfect CSI case, the proposed scheme still can provide acceptable outage performance given that the channel estimation error is bounded in a permissible interval.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.11
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• pp.5370-5393
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• 2019

In this paper, we consider a two-way relay non-orthogonal multiple access (TWR-NOMA) system with residual hardware impairments (RHIs) and channel estimation errors (CEEs), where two group users exchange their information via the decode-and-forward (DF) relay by using NOMA protocol. To evaluate the performance of the considered system, exact analytical expressions for the outage probability of the two groups users are derived in closed-form. Moreover, the asymptotic outage behavior in the high signal-to-noise ratio (SNR) regime is examined and the diversity order is derived and discussed. Numerical simulation results verify the accuracy of theoretical analyses, and show that: i) RHIs and CEEs have a deleterious effects on the outage probabilities; ii) CEEs have significant effects on the performance of the near user; iii) Due to the RHIs, CEEs, inter-group interference and intra-group interference, there exists error floors for the outage probability.