• Proceedings of the KIEE Conference
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• 1990.07a
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• pp.397-400
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• 1990

All the existing PWM voltage-controlled inverters, regardless of the advantages of the operation, have produced serious problems such as acoustic noise. In this raper, the PMW technique for acoustic noise reduction is implemented using randomly modulated carrier modulation. By modulating the triangular carrier in sinusoidal PWM with band-limited white noise, it is shown that the acoutic noise level and spectral density is reduced in a tone. This method shows great merit in application the AC motor drive system to particularly environment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.350-351
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• 2005

In this study, in order to develop the low temperature sintering multilayer piezoelectric transformer, PMW-PMN-PZT system ceramics were manufactured with the addition of sintering aids, and their dielectric and piezoelectric characteristics were investigated. At the composition ceramics sintered at $900^{\circ}C$, dielectric constant(${\varepsilon}r$), electromechanical coupling factor(kp) and mechanical quality factor(Qm) showed the optimal value of 1043, 0.44 and 793, respectively, for multilayer piezoelectric transformer application.

• Feed Journal
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• v.2 no.7
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• pp.100-103
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• 2004

PMWS는 최근 국내 양돈장에 가장 큰 피해를 입히는 질병으로 그 피해를 줄이기 위한 여러 가지 시도가 이루어지고 있지만 사실 농장간 시설, 관리상의 변이가 다양하므로 예방 및 컨트롤을 위한 표준 관리 지침을 설정하기가 어렵다.<중략>

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.1
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• pp.20-25
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• 2001

To develop the piezoelectric actuator, the structural, dielectric and piezoelectric properties and electric fieldinduced strain of the ceramics(Pb$\_$1-2/Ba$\_$x/)[Mg$\_$1/2/W$\_$1/2/)$\_$0.03/-Ni$\_$1/3/Nb$\_$2/3/)$\_$0.12/-(Zr$\_$0.5/Ti$\_$0.5/)$\_$0.85/]O$_3$(x=0, 0.01, 0.03, 0.05, 0.07, 0.1) were investigated with the substitution of Ba. The tetragonality of crystal structure and grain size decreased by the substitution of Ba. Curie temperature decreased due to the decrease of the tetragonality, and dielectric constants increased with the substitution of Ba. The coercive field, remnant polarization and electromechanical coupling factor also decreased, whereas the piezoelectric constatns d$\_$33/ and d$\_$31/ were showed the highest value of 430 and 209(x10$\^$-12/C/N), respectively, because of the increase of dielectric constant. The strain induced by 60Hz AC electric field had the maximum value of 204x10$\^$-6/Δℓ/ℓ at the substitution of Ba 3mol%. As the applied electric field approaches to the coercive field, the piezoelectric element is depolarized and the electric field induced strain revealed non-linearity.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.193-195
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• 1994

In this study, the structural, dielectric and piezoelectrical properties of $xPb(Mg_{1/2}W_{1/2})O_3-(1-x)[0.41Pb(Ni_{1/3}Nb_{2/3})O_3-0.36PbTiO_3-0.23P Zr)_3]$ (x=0, 0.01, 0.02, 0.03, 0.04, 0.05) system ceramics were investigated. The dielectric constant ${\varepsilon_{33}}^{\tau}$ at loon temperature increased up to 3mol% PMW and decreased with further PMW content. The specimen with 1mol% $Pb(Mg_{1/2}W_{1/2})O_3$, which has the ${\varepsilon_{33}}^{\tau}=5509$, kp=59[%] and $d_{33}=758{\times}10^{-12}[C/N]$, exhibits good characteristics.

• Journal of Information Processing Systems
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• v.10 no.2
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• pp.176-192
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• 2014

The realization of Wireless Multimedia Sensor Networks (WMSNs) has been fostered by the availability of low cost and low power CMOS devices. However, the transmission of bulk video data requires adequate bandwidth, which cannot be promised by single path communication on an intrinsically low resourced sensor network. Moreover, the distortion or artifacts in the video data and the adherence to delay threshold adds to the challenge. In this paper, we propose a two stage Quality of Service (QoS) guaranteeing scheme called Prioritized Multipath WMSN (PMW) for transmitting H.264 encoded video. Multipath selection based on QoS metrics is done in the first stage, while the second stage further prioritizes the paths for sending H.264 encoded video frames on the best available path. PMW uses two composite metrics that are comprised of hop-count, path energy, BER, and end-to-end delay. A color-coded assisted network maintenance and failure recovery scheme has also been proposed using (a) smart greedy mode, (b) walking back mode, and (c) path switchover. Moreover, feedback controlled adaptive video encoding can smartly tune the encoding parameters based on the perceived video quality. Computer simulation using OPNET validates that the proposed scheme significantly outperforms the conventional approaches on human eye perception and delay.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2847-2850
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• 2003

A input voltage conversion dimming control formula and a PMW dimming control formula which have been used for dimming control of CCFL driving inverter in TFT-LCD backlight, are the existing facilities so far, however, in this thesis the circuit is designed by applying The rover inverter that are able to measure output brightness according to changing of duty ratio at PWM and voltage. consequently, it's able to be confirmed that we can have dimming control more detailed than before.

• The Korea Swine Journal
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• v.28 no.9 s.325
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• pp.204-207
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• 2006

경기도 이천에 위치하고 있는 모든 250두의 도암농장은 2003년 2~3월 사이 pmws로 40~45일령 구간의 자돈 300여 마리가 폐사했다. 도암농장을 경영하고 있는 이명규 사장은 전문가의 도움을 받아 모돈 및 자돈의 백신관리와 사육환경의 변화로 이를 극복했고 지금까지 PSY(piglet per sow per year)26.1두,MSY(Market per sow per year)25.6두의 성적을 내고 있다. 이는 모돈1두당 연간 이유 후 출하까지 폐사가 0.5두이며, 현재 전국MSY가 15~16두임을 감안한다면 도암농장의 성적은 기적 같다고 말할 수 있다. 또한, 전국적으로 PED가 극성을 부릴 때, 이 질병에 대한 피해를 거의 보지 않은 도암농장의 경험과 사양관리방법을 이번 월간양돈에 소개하고자 한다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.2
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• pp.134-139
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• 2000

Ternary system of 40PMN-30PT-30PMW was prepared by using different reaction process. The PMN-PT was synthesized firstly, then it reacted to $PbWO_4$ as PbO and $WO_3$ sources. The dielectric constants were dependent on the density of sintered body and decreased with sintering temperature above $950^{\circ}C$. The highest dielectric constant was 24,000 in a sample sintered at $950^{\circ}C$ with the dielectric loss of 3 %. The temperature dependence of the dielectric constant were decreased with the increase of sintering temperature due to the appearance of double peak maxima. The lowest change in dielectric constant was -37-0 % from -55 to $125^{\circ}C$in a sample sintered at $1150^{\circ}C$ with dielectric constant of 9,900 at room temperature.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.9
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• pp.1331-1337
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• 2016

The aim of this study was to compare the growth performance, fiber characteristics of the pectoralis major muscle, and meat quality characteristics in the heavy weight (HW) and random bred control (RBC) quail lines and genders. The HW male exhibited more than two times greater body (245.7 vs 96.1 g, p<0.05) and pectoralis major muscle (PMW; 37.1 vs 11.1 g, p<0.05) weights compared to the RBC female. This growth performance in the HW line was associated with a greater muscle fiber area (1,502 vs $663.0{\mu}m^2$, p<0.001) compared to the RBC line. Greater muscle mass of the HW male was accompanied by a higher percentage of type IIB fiber compared to the HW female (64.0% vs 51.0%, p<0.05). However, muscle fiber hyperplasia (increase in fiber number) has had a somewhat limited effect on PMW between the two lines. On the other hand, the HW line harboring a higher proportion of type IIB fiber showed rapid pH decline at the early postmortem period (6.23 vs 6.41, p<0.05) and lighter meat surface (53.5 vs 47.3, p<0.05) compared to the RBC line harboring a lower proportion of type IIB fiber. There were no significant differences observed in the measurement of water-holding capacity including drip loss (2.74% vs 3.07%, p>0.05) and cooking loss (21.9% vs 20.4%, p>0.05) between the HW and RBC lines. Therefore, the HW quail line developed by selection from the RBC quail, was slightly different in the meat quality characteristics compared to the RBC line, and a marked difference was found in growth performance between the two quail lines.