• Electrical & Electronic Materials
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• v.11 no.10
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• pp.46-52
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• 1998

In this study, polarization switching characteristics of Pb(ZrxTil-x)O3 (PZT) thin films were investigated. Switching times(ts) were found to be decreased as the Zr mol% was increased. But, the switching peak currents(Imax) showed the largest value at 50 mol% Zr. As a result of this experiment, ts was found to be depended on the remanent polarization and coercive field and also Imax strongly depended on the dielectric constant of PZT thin films. In order to investigate the partial switching kinetics of PZT thin films, short and relatively small voltage pulses were applied to the MFM(metalferroelectric metal) PZT capacitors and polarization switching curves were measured with a variation of the total width of the applied pulses. Also, the switching curves were measured at different applied voltages(4, 8, 10, 12 and 14 volts). As the applied voltages increased, ts and Imax were found to be decreased and increased, respectively. In case of fatigued specimen which we applied $\pm$10 volts square pulse for 1010 cycles, ts and Imax were found to be shorter and smaller than those of virgin specimens. This is due to the decrease of the remanent polarization and the increase of the coercive field.

• Journal of Veterinary Clinics
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• v.37 no.1
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• pp.28-33
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• 2020

The aims of this study were to obtain the normal ranges of enhancement parameters for salivary gland in dynamic CT and to investigate the effects of fasting time on contrast enhancement in clinically normal beagle dogs. With five healthy beagle dogs, dynamic CT examination was performed according to fasting times (as fasting times, 12hours, 0 min, 20 min, 40 min, 1 hours, 6 hours, 24 hours). In normal beagles with 12hours fasting, enhancement parameters through the preliminary study were as follows: ImaxA - 472 .49 ± 19.01 HU; ImaxS - 138.95 ± 6.2 5 HU; TmaxA - 25.8 ± 1.79 sec; TmaxS - 69.0 ± 23.11 sec; Teq - 80.5 ± 6.61 sec; T-Aeq - 54.5 ± 5.51 sec (Imax - peak enhancement; Tmax - time to peak enhancement; Teq - time to equilibrium phase; T-Aeq - time between peak enhancement in the common carotid artery and onset of the equilibrium phase; A - common carotid; S - submandibular gland; HU - Hounsfield unit). Additionally, ImaxA and ImaxS were significantly increased in 40 min after eating. Because these results associated with postprandial hemodynamic changes can make the diagnosis of salivary gland diseases more difficult, sufficient fasting time is important for accurate diagnosis.

• The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.4 no.4
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• pp.43-51
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• 1990

레이저 비임이 대기중을 전파할 때 고류(turbulence)의 영향을 고려해야 한다. 고류의 영향에 의한 프린지 시도는 extended Huygens-Fresnel principle을 도입하여 타원체로 간주할 수 있는 프린지 체적에서 장의 전 분포를 시하고 이 전 분포로부터 평균 강도분포를 얻었으며, 평균 강도분포를 구하기 위해 Fourier-Bessel적분을 행하였다. 평균 강도분포에서 최대 평균 강도분포max 및 최소 평균 강도분포 min을 얻었으며, 이 식들을 프린지 시도의 정의 식 V=(Imax-Imax)/(Imax+Imin)에 적용하였다. 본 논문에서는 광원으로 파장 =4880[]인 아르곤 레이저를 사용하였고 광원의 모우드는 TEM..모우드로 하였다. 또한 비임의 교각 =5˚, 광원으로부터 프린지 체적 까지의 거리 L=10[m], en 광원간의 거리 B=(2tan /2)L, 특성 비임 반경 =2 /[ ( /2)]을 이용하여 프린지 시도에 관한 결과를 얻었으며, 이 결과에 의하면 L'( / ·L)에 대한 변수 r의 비 r/L'= 에서 V=1이고, r/L=0.1에서 프린지 시도가 감소한다. 또 강 고 류인 경우와 약 고 류인 경우에 대해 프린지 시도를 비교하였을 때 강 고류에서 감소폭이 크다는 사실을 알 수 있었다.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.47-51
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• 2015

Ground Level Enhancements (GLEs) in cosmic ray intensity observed during the period of 1997-2012 have been studied with energetic solar features and disturbances in solar wind plasma parameters and it is seen that all the GLEs have been found to be associated with coronal mass ejections, hard X-ray solar flares and solar radio bursts. All the GLEs have also been found to be associated with sudden jumps in solar proton flux of energy of ${\geq}60Mev$. A positive correlation with correlation coefficient of 0.48 has been found between the maximum percentage intensity (Imax%) of Ground Level Enhancements and the peak value of solar proton flux of energy (${\geq}60Mev$). All the Ground Level Enhancements have been found to be associated with jumps in solar wind plasma velocity (JSWV) events. A positive correlation with correlation coefficient of 0.43 has been found between the maximum percentage intensity (Imax %) of Ground Level Enhancements and the peak value of solar wind plasma velocity of associated (JSWV) events. All the Ground Level Enhancements have been found to be associated with jumps in solar wind plasma pressure (JSWP) events. A positive correlation with correlation coefficient of 0.67 has been found between the maximum percentage intensity (Imax %) of Ground Level Enhancements and the peak value of solar wind plasma pressure of associated (JSWP) events and of 0.68 between the maximum percentage intensity (Imax %) of Ground Level Enhancements and the magnitude of the jump in solar wind plasma pressure of associated (JSWP) events.

• Journal of Digital Convergence
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• v.15 no.8
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• pp.375-381
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• 2017

The America film, Beauty and Beast has grossed over 4,273,401 after being released for 21 days. The growth of movie profit in the video market is also developing rapidly. In this paper, we will focus on the PLF(Premium Large-Format) video technology, because PLF video technology can help audience to enhance the sense of 'immersion' and enjoy a different visual feast. In PLF video technology, IMAX, screen X, 360 degrees circular screen are the most important formats. By comparative analysis of these 3 formats, the biggest difference is their number of screens and appearance. Based on the result we can understand the 3 kinds of PLF platforms better and help us to make a choice between them. In addition, further research about the manufacture method of PLF technology will be discussed.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.40 no.1
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• pp.50-58
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• 2003

Recently we have built a VR(Virtual Reality) theater in Kyongju, Korea, which combines the advantages of VR and IMAX theater. The VR theater provides a virtual environment for several hundreds of people at the same time. The VR theater can be characterized by a single shared screen and by multiple inputs from several hundreds of people. In this case, multi-user interaction is different from that of networked VR systems and must be reconsidered. This paper defines the multi-user interaction in such a VR theater as Audience Interaction, and discusses key issues for the implementation of the Audience Interaction. This paper also presents a real implementation example in the Kyongju VR theater.

• Korean journal of food and cookery science
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• v.12 no.2
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• pp.123-128
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• 1996

Tenderness of loin and brisket muscles of Korean and imported beef was measured using the Time-lntensity (Tl) techniques. From the Tl curve, the Rx, Imax, Dur and AUC parameters were determined. For the loin muscle, Korean beef showed significantly (p < 0.05) larger Rx, Imax, and AUC. This result represents Korean beef loin has higher tenderness than that of imported one. For the brisket muscle, imported beef show.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.64-71
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• 1999

Seismicity of the Korean Peninsula shows intraplate seismicity that has irregular pattern in both time and space. Seismic data of the Korean peninsula consists of historical earthquakes and instrumental earthquakes. In this study we devide these data into complete part and incomplete part and considering earthquake size uncertainty estimate seismic hazard parameters - activity rate λ, b value of Gutenberg-Richter relation and maximum possible earthquake IMAX by statistical method in each major tectonic provinces. These estimated values are expected to be important input parameters in probabilistic seismic hazard analysis and evaluation of design earthquake.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.164-168
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• 1985

In order to enhance herbicidal efficacy of amide and diazine herbicides, synergistic effects of pretilachlor and pyrazoxyfene or butachlor and pyrazolate on control of Cyperus serotinus were determined by isobole method. Interaction indices(I) between pretilachlor and pyrazoxyfene treated at 0 and 3rd leaf stage were 2.64 and 2.07 and hence showed synergistic effect for control of Cyperus serotinus. The points indicated Imax between pretilachlor and pyrazoxyfene were 0.7:1.3 g ai/a and 9.0:20.5 g ai/a at 0 and 3rd leaf stage, respectively. Combination of butachlor and pyrazolate showed synergistic effect(1=1.57) on control of Cyperus serorinus and point indicated Imax was 48.0:20.9 g ai/a.

• Phonetics and Speech Sciences
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• v.13 no.4
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• pp.89-100
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• 2021

This study compared the voice range profiles (VRPs) with glissando and simplified VRP methods with 57 men who were in premutation (8-13 years), mutation (11-16 years), and postmutation (10-24 years) stages. The difference between modal and falsetto areas measured in two VRP methods was also compared. As the results, the average fundamental frequency (F0) was in the order of premuaton>mutation>postmutation. The maximum F0 (F0max), the range of F0 (F0range), the maximum intensity (Imax), and the range of intensity (Irange) were the lowest in the mutation stage, and these variables were higher in falsetto area than in modal area in both methods. In addition, most variables of VRP in glissando were higher than in simplified VRP, but the differences were not significant. This study showed that, in men in mutation stage, due to the temporary anatomical and physiological changes of the larynx, the mechanism of the vocal folds vibration changes and VRP shows a different pattern from that of other age groups. Both the VRPs of glissando and simplifed VRP are suitable for clinical practice by experienced examiners. And it is necessary to measure not only the falsetto area but also the modal area when measuring VRP.