• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권5호
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• pp.2009-2028
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• 2018

Considering a dual-hop energy-harvesting (EH) relaying system, this paper advocates novel relaying protocols based on adaptive time power switching-based relaying (AR) architecture for amplify-and-forward (AF) mode. We introduce novel system model relaying network with impacts of co-channel interference (CCI) and derive analytical expressions for the average harvested energy, outage probability, and the optimal throughput of the information transmission link, taking into account the effect of CCI from neighbor cellular users. In particular, we consider such neighbor users procedure CCI both on the relay and destination nodes. Theoretical results show that, in comparison with the conventional solutions, the proposed model can achieve optimal throughput efficiency for sufficiently small threshold SNR with condition of reasonable controlling time switching fractions and power splitting fractions in concerned AR protocol. We also explore impacts of transmission distances in each hop, transmission rate, the other key parameters of AR to throughput performance for different channel models. Simulation results are presented to corroborate the proposed methodology.

• 전기학회논문지
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• 제61권10호
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• pp.1489-1495
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• 2012

In this study, the active noise control experiment has been performed using induction motor noises. While the noises were measured, a induction motor was operated in different speed. For the simulation of ANC(Active Noise Control), test-bed is composed a multi-channel ANC system was constructed. In order to compare the control performance, we performed noise reduction simulations of ANC by Co-FXLMS algorithm and FXLMS algorithm. Through the simulation results, we confirmed that convergence performance and noise decrease effect of the proposed Co-FXLMS algorithm have been improved from existing FXLMS algorithm.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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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%.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권7호
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• pp.3134-3155
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• 2020

In this paper, we study the joint radio and computational resource allocation in the ultra-dense mobile-edge computing networks. In which, the scenario which including both computation offloading and communication service is discussed. That is, some mobile users ask for computation offloading, while the others ask for communication with the minimum communication rate requirements. We formulate the problem as a joint channel assignment, power control and computational resource allocation to minimize the offloading cost of computing offloading, with the precondition that the transmission rate of communication nodes are satisfied. Since the formulated problem is a mixed-integer nonlinear programming (MINLP), which is NP-hard. By leveraging the particular mathematical structure of the problem, i.e., the computational resource allocation variable is independent with other variables in the objective function and constraints, and then the original problem is decomposed into a computational resource allocation subproblem and a joint channel assignment and power allocation subproblem. Since the former is a convex programming, the KKT (Karush-Kuhn-Tucker) conditions can be used to find the closed optimal solution. For the latter, which is still NP-hard, is further decomposed into two subproblems, i.e., the power allocation and the channel assignment, to optimize alternatively. Finally, two heuristic algorithms are proposed, i.e., the Co-channel Equal Power allocation algorithm (CEP) and the Enhanced CEP (ECEP) algorithm to obtain the suboptimal solutions. Numerical results are presented at last to verify the performance of the proposed algorithms.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2011년도 한국우주과학회보 제20권1호
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• pp.20.1-20.1
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• 2011

We present the results of far-ultraviolet (FUV) observations of comet C/2001 Q4 (NEAT) obtained with Far-ultraviolet Imaging Spectrograph (FIMS) on board the Korean microsatellite STSAT-1, which operated at an altitude of 700 km in a sun-synchronous orbit. FIMS is a dual-channel imaging spectrograph (S channel 900-1150 ${\AA}$, L channel 1350-1750 ${\AA}$, ${\lambda}/{\Box}{\lambda}$ ~ 550) with large image fields of view (S: $4^{\circ}.0{\times}4'.6$, L: $7^{\circ}.5{\times}4'.3$, angular resolution 5'-10') optimized for the observation of diffuse emission of astrophysical radiation. Comet C/2001 Q4 (NEAT) was observed with a scanning survey mode when it was located around the perihelion between 8 and 15 May 2004. Several important emission lines were detected including S I (1425, 1474 ${\AA}$), C I (1561, 1657 ${\AA}$) and several emission lines of CO $A1{\cap}-X1{\sum}+$ system in the L channel. We estimated QCO = ($2.58\;{\pm}\;0.64)\;{\times}\;1028$ s-1 from the production rate of CO 1510 ${\AA}$. We obtained L-channel image which have map size of $5^{\circ}{\times}5^{\circ}$. The image was constructed for the wavelength band of L-channel (1350-1750 ${\AA}$).We also obtained radial profile of S I, C I, CO with line fitting from central coma.

• 천문학회보
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• 제37권2호
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• pp.107.1-107.1
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• 2012

We present the results of far-ultraviolet (FUV) observations of comet C/2001 Q4 (NEAT) obtained with Far-ultraviolet Imaging Spectrograph (FIMS) on board the Korean microsatellite STSAT-1, which operated at an altitude of 700 km in a sun-synchronous orbit. FIMS is a dual-channel imaging spectrograph (S channel 900-1150 ${\AA}$, L channel 1350-1750 ${\AA}$, ${\lambda}/{\Delta}{\lambda}$ ~ 550) with large image fields of view (S: $4^{\circ}.0{\times}4^{\prime}.6$, L: $7^{\circ}.5{\times}4^{\prime}.3$, angular resolution 5'-10') optimized for the observation of diffuse emission of astrophysical radiation. Comet C/2001 Q4 (NEAT) was observed with a scanning survey mode when it was located around the perihelion between 8 and 15 May 2004. Several important emission lines were detected including S I (1425, 1474 ${\AA}$), C I (1561, 1657 ${\AA}$) and several emission lines of CO $A^1{\Pi}-X^1{\Sigma}^+$ system in the L channel. Production rates of the notable molecules, such as C I, S I and CO, were estimated from the photon fluxes of these spectral lines and compared with previous observations. We compare the flux and the production rates in the radius of $3{\times}10^5$ km with $20{\times}10^5$ km from the central coma. We obtained L-channel image which have map size $5^{\circ}{\times}5^{\circ}$ The image was constructed for the wavelength band of L-channel (1350 - 1710 ${\AA}$. We also present the radial profiles of S I, C I, CO obtained from the spectral images of the central coma. The radial profiles of $2{\times}10^6$ km region are compared with the Haser model.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권5호
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• pp.1976-1997
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• 2016

This paper investigates the problem of co-tier interference mitigation for dynamic small- cell networks, in which the load of each small-cell varies with the number of active associated small-cell users (SUs). Due to the fact that most small-cell base stations (SBSs) are deployed in an ad-hoc manner, the problem of reducing co-tier interference caused by dynamic loads in a distributed fashion is quite challenging. First, we propose a new distributed channel allocation method for small-cells with dynamic loads and define a dynamic interference graph. Based on this approach, we formulate the problem as a dynamic interference graph game and prove that the game is a potential game and has at least one pure strategy Nash equilibrium (NE) point. Moreover, we show that the best pure strategy NE point minimizes the expectation of the aggregate dynamic co-tier interference in the small-cell network. A distributed dynamic learning algorithm is then designed to achieve NE of the game, in which each SBS is unaware of the probability distributions of its own and other SBSs' dynamic loads. Simulation results show that the proposed approach can mitigate dynamic co-tier interference effectively and significantly outperform random channel selection.

• The Korean Journal of Physiology and Pharmacology
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• 제25권3호
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• pp.227-237
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• 2021

Carbon monoxide (CO) is a cardioprotectant and potential cardiovascular therapeutic agent. Human cardiac fibroblasts (HCFs) are important determinants of myocardial structure and function. Large-conductance Ca2+-activated K+ (BK) channel is a potential therapeutic target for cardiovascular disease. We investigated whether CO modulates BK channels and the signaling pathways in HCFs using whole-cell mode patch-clamp recordings. CO-releasing molecules (CORMs; CORM-2 and CORM-3) significantly increased the amplitudes of BK currents (IBK). The CO-induced stimulating effects on IBK were blocked by pre-treatment with specific nitric oxide synthase (NOS) blockers (L-NG-monomethyl arginine citrate and L-NG-nitroarginine methyl ester). 8-bromo-cyclic GMP increased IBK. KT5823 (inhibits PKG) or ODQ (inhibits soluble guanylate cyclase) blocked the CO-stimulating effect on IBK. Moreover, 8-bromo-cyclic AMP also increased IBK, and pre-treatment with KT5720 (inhibits PKA) or SQ22536 (inhibits adenylate cyclase) blocked the CO effect. Pre-treatment with N-ethylmaleimide (a thiol-alkylating reagent) also blocked the CO effect on IBK, and DL-dithiothreitol (a reducing agent) reversed the CO effect. These data suggest that CO activates IBK through NO via the NOS and through the PKG, PKA, and S-nitrosylation pathways.

• ETRI Journal
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• 제32권4호
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• pp.603-606
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• 2010

In this letter, we propose a channel estimation algorithm based on incremental pilots. These are pilots additionally inserted after puncturing the modulated orthogonal frequency division multiplexing (OFDM) symbols to enhance channel estimation performance without lowering bandwidth efficiency. A low-density parity-check code puncturing scheme is also proposed to prevent the performance degradation due to the codeword bit loss caused by punctured OFDM symbols.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.915-916
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• 2005