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Riaz, Sidra;Kim, Jihwan;Park, Unsang
- KSII Transactions on Internet and Information Systems (TIIS)
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- v.12 no.6
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- pp.2697-2710
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- 2018
Owing to the development of Internet of Things (IoT), the fifth-generation (5G) wireless communication is going to foresee a substantial increase of mobile traffic demand. Energy efficiency and spectral efficiency are the challenges in a 5G network. Non-orthogonal multiple access (NOMA) is a promising technique to increase the system efficiency by adaptive power control (PC) in a 5G network. This paper proposes an efficient PC scheme based on evolutionary game theory (EGT) model for uplink power-domain NOMA system. The proposed PC scheme allows users to adaptively adjusts their transmit power level in order to improve their payoffs or throughput which results in an increase of the system efficiency. In order to separate the user signals, a successive interference cancellation (SIC) receiver installed at the base station (BS) site. The simulation results demonstrate that the proposed EGT-based PC scheme outperforms the traditional game theory-based PC schemes and orthogonal multiple access (OMA) in terms of energy efficiency and spectral efficiency.
https://doi.org/10.3837/tiis.2018.06.014 인용 PDF KSCI

Heo, Sung-Jung
- Journal of the Korean Society for Precision Engineering
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- v.25 no.12
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- pp.47-54
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- 2008
Hard turning process can be defined as a single-point machining process carried out on "hard" materials. The process is intended to replace or limit traditional grinding operations that are expensive, environmentally unfriendly, and inflexible. The purpose of this study is to achieve a systematic understanding of machining characteristics and the effects of machining parameters on cutting force, tool wear shape and chip formation by the outer cutting of a kind of wear resistant tungsten carbide V30. Hard turning experiments were carried out on this alloy using the PCD (Poly Crystalline Diamond), cBN (cubic Boron Nitride) and PcBN (Polycrystalline cubic Boron Nitride) cutting tools. The PcBN and the usual cBN tools were used to be compare with the PCD tool and the dry turning was carried out. The PcBN is attractive as the tool material which replaces the PCD. The tool wear width and cutting force were measured, and the worn tool and chip were observed. The difference of the tool wear mechanism among the three tool materials was investigated.
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Jin, You-Xun;Shin, Kyong-Oh;Park, Myung-Yong;Lee, Shin-Hee;Park, Byeong-Deog;Oh, Sei-Kwan;Yoo, Hwan-Soo;Lee, Yong-Moon
- Biomolecules & Therapeutics
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- v.19 no.1
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- pp.134-139
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- 2011
Sphingosine kinase (SPHK) has a central role to control cell death and cell proliferation, which is suggested as a sphingolipid rheostat by regulating the levels between ceramide and sphingosine 1-phosphate (S1P). Therefore, physiological regulators of SPHK will be a good candidate to develop a new targeted drug. For this purpose, a series of synthetic pseudoceramides were tested by SPHK assay either cell-based or cell-free system. K10PC-5 strongly inhibited SPHK, while K6PC-5 activated SPHK in cell-free system. Specifically, K6PC-5 activated SPHK under the co-treatment with $50\;{\mu}M$ dimethylsphingosine (DMS), a SPHK inhibitor. Collectively, we developed a simple SPHK assay system to find SPHK regulatory pseudoceramide compounds, K10PC-5 and K6PC-5 which may be useful to cancer treatment or immune regulation like FTY720, a synthetic sphingolipid mimetic compound.
https://doi.org/10.4062/biomolther.2011.19.1.134 인용 PDF KSCI

Lee, Sun-Hwan;Lee, Hyuek-Jae
- Journal of the Institute of Convergence Signal Processing
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- v.12 no.1
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- pp.50-55
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- 2011
In this paper, we propose and demonstrate an effective video advertising method for on-line shopping malls. For the Internet advertising, we make a mouse with a small OLED display that can communicate with PC's Internet network. Without displaying the teasing Pop-ups on the PC's monitor, the advertising for a shopping mall is directly sent to the OLED display on the mouse. Also, the proposed method has merits of sending the advertising based on customer's preference by using IP multicasting, which the customer can select an advertising category in advance. When the customer want to buy an item on the OLED display, the detail advertising can be immediately accessed through a Web browser on PC's monitor by pushing a special button on the mouse.
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