• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.7
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• pp.1091-1097
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• 2022

In this paper, we implement the eXclusive OR-based Cast (XC) system that is a video streaming system using exclusive OR operations, and measure various performance metrics in wireless local area network (WLAN) environments. In addition, we investigate the performance improvement of the XC system considering various practical video streaming environments, while conventional studies analyzed the performance of XC through computer simulations in limited environments. To this end, we propose new control messages such as STR_REQ_MSG (SRM) that clients transmit to a video streaming server and STR_CON_MSG (SCM) that is used for the video streaming server to control the clients, and develop a new protocol by using the new control messages. According to the various measurement results using the implemented XC system, XC video streaming system can reduce the consumption of network bandwidth by 8.6% on average and up to 25% compared to the conventional video streaming system. In addition, the outage probability can be also reduced up to 76%.

• Journal of the Institute of Convergence Signal Processing
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• v.10 no.3
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• pp.193-197
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• 2009

In this paper, we study on design of vehicle control system which is based on ${\mu}C/OS-II$, We component a electric motor drive system for simulator because the most of vehicle part use electric motor for actuator. We use the XC2287 microcontroller which is often used vehicle body controller because XC2287 guarantee high confidence and durability in vehicle industry. The electric motor control system derive PWM from general I/O port in XC2287 microcontroller. The signal is supplied at electric motor after amplifying that using driver circuit. The user control duty of PWM signal through controlling potentiometer which is connected to XC2287. through that, the user control speed of electric motor. we synchronize both input process via controlling potentiometer and PWM output process using semaphore. we verify porting of ${\mu}C/OS-II$ via experimentation.

• Journal of Microbiology and Biotechnology
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• v.17 no.3
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• pp.539-542
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• 2007

Glycosyltransferase family 1 (UOT) uses small chemicals including phenolics, antibiotics, and alkaloids as substrates to have an influence in biological activities. A glycosyltransferase (XcGT-2) from Xanthomonas campestris was cloned and consisted of a 1,257 bp open reading frame encoding a 45.5 kDa protein. In order to use this for the modification of phenolic compounds, XcGT-2 was expressed in Escherichia coli as a glutathione S-transferase fusion protein. With the E. coli transformant expressing XcGT-2, biotransformation of flavonoids was carried out. Flavonoids having a double bond between carbons 2 and 3, and hydroxyl groups at both C-3' and C-4', were glycosylated and the glycosylation position was determined to be at the hydroxyl group of C-3', using nuclear magnetic resonance spectroscopy. These results showed that XcGT-2 regiospecifically transferred a glucose molecule to the 3'-hydroxyl group of flavonoids containing both 3' and 4'-hydroxyl groups.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2628-2632
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• 2011

The nucleophilic substitution reactions of Y-O-aryl phenyl phosphonochloridothioates with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are kinetically investigated in acetonitrile at $55.0^{\circ}C$. The deuterium kinetic isotope effects (DKIEs) invariably increase from an extremely large secondary inverse ($k_H/k_D$ = 0.439; min) to a primary normal ($k_H/k_D$ = 1.34; max) as both substituents of nucleophile (X) and substrate (Y) change from electron-donating to electron-withdrawing. These results are opposite to the DKIEs on Y-O-aryl methyl phosphonochloridothioates, and can be rationalized by the gradual transition state (TS) variation from backside to frontside attack. The trigonal bipyramidal pentacoordinate TS is proposed for a backside attack, while the hydrogen-bonded, four-center-type TS is proposed for a frontside attack. The negative values of the cross-interaction constants (${\rho}_{XY(H)}$ = -0.38 for $XC_6H_4NH_2$ and ${\rho}_{XY(D)}$ = -0.29 for $XC_6H_4ND_2$) indicate that the reactions proceed by a concerted $S_N2$ mechanism.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.8C
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• pp.812-818
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• 2002

반도체 기술과 멀티기디어 통신기술이 발달하면서 고품위의 영상과 다중 채널의 오디오에 관심을 갖게되었다. 특히 DVD 시장의 급성장으로 인하여 고품질의 영상 및 오디오 필요성이 중요한 기술로 대두되었다. MPEG-Audio 표준안은 어떠한 비트율도 지원한다. 본 논문에서는 MPEG-Audio의 핵심부분인 필터부분을 DALUT (Distributed Arithmetic Look-Up Table)방식을 사용하여 FPGA(Field Programmable Gate Array)에 구현하였다. 고속 필터를 설계하기 위해서 승산기 대신에 DALUT를 사용하였으며 최소 10㎒에서 최대 30㎒ 사이에서 동작한다. 본 논문의 설계는 모두 VHDL로 구현하였으며, 알고리즘 검증은 C언어를 사용하였다. VHDL의 시뮬레이션은 ALDEC사의 Active-HDL5.1과 Synopsys사의 vhdlsim을 사용하였고, 합성은 Synopsys사의 design-analyzer를 사용하였다. 타겟 라이브러리는 XILINX사의 XC4010E, XC4020EX, XC4052XL을 사용하였으며, P＆R 툴은 XACT Ml.4를 사용하였다.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.150-156
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• 2014

In this study, we implemented a research for improving performance of redox flow battery (RFB) via enhancing reaction rate of vanadium reaction ($[VO]^{2+}/[VO_2]^+$) that was a rate determining step. For doing that, porous catalyst, CMK3 was employed and its perfoamance was compared with that of Vulcan(XC-72) and commercial Pt/C (Johnson-Matthey Pt 20wt.%). Cyclic voltammetry (CV) was used for inspecting reactivity, while its structural feature was measured by TEM and BET&BJH. Also, Charge-discharge trend was evaluated by single cell tests. As result, CMK3 showed 6 times better catalytic activity and twice better reversibility than Vulcan(XC-72), while it showed larger surface area than Vulcan XR due to its porous structure. Furthermore, CMK3 indicated 85% of reactivity and reversibility of commercial Pt/C despite its Pt-less situation. In single cell tests, when RFB adopted CMK3 as catalyst for positive electrode, its charge-discharge curve result was better than that adopted commercial Pt/C.

• The Journal of the Acoustical Society of Korea
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• v.23 no.8
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• pp.554-561
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• 2004

As the technologies of semiconductor and multimedia communication have been improved. the high-quality video and the multi-channel audio have been highlighted. MPEG Audio Layer 3 decoder has been implemented as a Processor using a standard. Since the synthesis filter of MPEG-1 Audio Layer 3 decoder requires the most outstanding operation in the entire decoder. the synthesis filter that can reduce the amount of operation is needed for the design of the high-speed processor. Therefore, in this paper, the synthesis filter. the most important part of MPEG Audio, is materialized in FPGA using the method of DAULT (distributed arithemetic look-up table). For the design of high-speed synthesis filter, the DAULT method is used instead of a multiplier and a Pipeline structure is used. The Performance improvement by 30% is obtained by additionally making the result of multiplication of data with cosine function into the table. All hardware design of this Paper are described using VHDL (VHIC Hardware Description Language) Active-HDL 6.1 of ALDEC is used for VHDL simulation and Synplify Pro 7.2V is used for Model-sim and synthesis. The corresponding library is materialized by XC4013E and XC4020EX. XC4052XL of XILINX and XACT M1.4 is used for P&R tool. The materialized processor operates from 20MHz to 70MHz.

• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.689-692
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• 2005

In order to improve the electrochemical performances of Li-ion batteries when spinel $LiMn_2O_4$ is employed as a cathode active material, binary conductive agents were prepared using two different particle-sized carbons like Super P Black and $Vulcan^{(R)}$ XC-72R. The electrochemical performances of the $LiMn_2O_4$ cell system using binary conductive agents were evaluated in terms of specific charge and discharge capacities and cycle life. The cell with binary conductive agent in the 3:7 weight ratios of Super P Black and $Vulcan^{(R)}$ XC-72R showed better electrochemical performances due to the proper combination of ionic diffusion rate and electric contact.

• Journal of IKEEE
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• v.20 no.4
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• pp.344-350
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• 2016

In this Paper, we propose an optimized method of hardware design based on Field Programmable Gate Array (FPGA) to detect rotated angle of high definition image about Extreme Contour Point (ECP) algorithm with moving video image could be not happened to translation motion, but also physical rotation motion. It was evaluated by XC7Z020 xc7z020-3clg400 FPGA board by using xilinx 14.2 tool. The much well-known method, the Coordinate Rotation Digital Integrated Computation (CORDIC) is an algorithm to estimate rotated angle between point and point. Through the result both ECP and CORDIC, our proposed design are confirmed to have similar operating speed of about 4ns with CORDIC. However, it is verified to have high performance result in terms of the hardware cost, is much better than CORDIC with cost reduction of registers and Look Up Tables (LUTs) of 108% and 91%, respectively.

• Journal of Sericultural and Entomological Science
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• v.35 no.2
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• pp.100-104
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• 1993

The genetics analysis for weight of matured silkworm(WMS) and number of eggs produced per moth(NEM) was studied by the seven parents diallel. Mean squares of additive effect, dominant effect, maternal effect and reciprocal effect were significant for two characters observed. The component of genetic variance analysis for WMS and NEM showed that dominant effect was higher than additive effect. Narrow sense heritability(h2ns) estimates were 0.773 and 0.228, in the WMS and NEM. The estimate of broad sense heritability(h2bs) value was higher than that of h2ns because of the low importance of dominance effect. Incomplete dominance was shown by Vr-Wr graphic analysis in the weight of matured silkworm and overdominance in the number of eggs produced per moth. In general combining ability effect, Jam 107 and Jam 124 was showed positively high for WMS and Jam 107 and S1 was expressed positively high for NEM. In specific combining ability effect, hybrids in S1XC51, S1XJam124 and Jam 107XJam 108 were exhibited positively high for WMS and Jam 107XN63, S1XC51, N74XJam 108 and Jam 107XJam 108 were found positively high for NEM.