• Title/Summary/Keyword: ${\pi}$

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Eliashberg Calculation of the Momentum-Resolved Self-Energy for the Cuprate Superconductors Induced by the Spin Fluctuations (구리 산화물 계열 초전도체에서의 스핀 요동에 의한 자체 에너지의 엘리아시버그 계산)

  • Hong, Seung-Hwan;Choi, Han-Yong
    • Progress in Superconductivity
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    • v.13 no.3
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    • pp.146-150
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    • 2012
  • We solve the momentum resolved d-wave Eliashberg equation employing the magnetic excitation spectrum from the inelastic neutron scattering on the LSCO superconductors reported by Vignolle et al. The magnetic excitation spectrum exhibits 2 peaks: a sharp incommensurate peak at 18 meV at momentum (${\pi}$, ${\pi}{\pm}{\delta}$) and (${\pi}{\pm}{\delta}$, ${\pi}$) and another broad peak near 40~70 meV at momentum (${\pi}$, ${\pi}$). Above 70 meV, the magnetic excitation spectrum has a long tail that is shaped into a circle centered at (${\pi}$, ${\pi}$) with ${\delta}$. The sign of the real part of the self-energy is determined by the momentum position of the peaks of the magnetic excitation spectrum and bare dispersion. We will discuss the effects of the each component of the magnetic excitation spectrum on the self-energy, the pairing self-energy.

High Performance Control of SynRM Drive using FNN based PI Controller (FNN 기반 PI 제어기를 이용한 SynRM 드라이브의 고성능 제어)

  • Jung, Byung-Jin;Ko, Jae-Sub;Choi, Jung-Sik;Kim, Do-Yeon;Chung, Dong-Hwa
    • Proceedings of the KIEE Conference
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    • 2008.10c
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    • pp.68-70
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    • 2008
  • This paper proposes FNN based PI controller for high performance control of SynRM Drive. Traditional PI controller can't be obtained good performance because it has fixed gain. Therefore, in this paper, FNN based PI controller that gain of PI controller is tuned use FNN proposes. FNN based PI controller proposed in this paper can be obtained excellent performance more than traditional PI controller. Algorithm proposed in this paper make a analysis and prove valid.

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A Study on Cho-pi (초피고)

  • 박춘순
    • Journal of the Korean Society of Costume
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    • v.42
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    • pp.25-42
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    • 1999
  • This study aims to prove that the fact that minority races in the north-eastern region contributed sable skin to the Quing Dynasty might be related to Cho-Sun of King Muryong in the Warring states period because documents are available here and there. The Chinese had been using fur clothing since ancient times but we cannot find any mention that they had used sable skin. This fact shows that sable skin was not widely used because of its rarity. Cho-pi had been used in making costume on a large scale from the period of the Han Dynasty to the end of the Quing Dynasty. Cho-pi was very rare and it was used as a measure of bartering. China met the demand of cho-pi by the Cho-pi contributions of the frontier minority races. It might bwe that the high demand of Cho-pi in the Quing Dynasty forced minority races to contribute Cho-pi The documents concerning Cho-pi in the north-eastern region are of great importance not only to the history of costume but also to the history of ancient economy and national culture.

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A Study on the Fuzzy Modifier of PI Control for Improvement of Tracking properties in Induction Motor System

  • Kim, Yuen-Chung;Ahn, Jeong-Joon;Kim, Jae-Mun;Won, Chung-Yuen;Kim, Young-Real
    • Proceedings of the KIPE Conference
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    • 1998.10a
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    • pp.7-10
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    • 1998
  • Because of simple control algorithm and easy implementation, the conventional PI controller has been widely used in industrial application. But, it is very difficult to find the optimal PI control gain. Therefore, in improperly tuned PI controller or parameter variation, to obtain optimal performance, the novel PI controller, which consist of conventional PI controller and 4-rule based fuzzy logic, are presented in this paper. The novel PI controller which exhibits a stabilizing effects on the closed-loop system, has good robustness regarding the improperly tuned PI controller or parameter variation. The simulations are performed to verify the capability of proposed control method on induction motor.

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A Study on wide viewing angle and fast response time using new VA-$\pi$ cell mode (새로운 VA-$\pi$ 셀 모드를 이용한 광시야각과 고속 응답에 관한 연구)

  • 서대식;이정호
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.4
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    • pp.332-336
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    • 2000
  • We have developed a novel vertical-alignment(VA) -$\pi$ cell mode that provides a wide viewing angle and fast response times for nematic liquid crystal(NLC) with negative dielectric anisotropy on a homeotropic polymide(PI) surfaces. Good voltage-transmittance curves and low driving voltages were achieved with the new VA-$\pi$ cell mode without a negative compensation film. Iso-viewing angle characteristics using the new VA-$\pi$ cell mode without a negative compensation film was also successfully observed. As well a fast response time of 31.7 ms for a new VA-$\pi$ mode was measured. Consequently the iso-viewing angel fast response time and low driving voltage characteristics using a VA-$\pi$ cell can be achieved.

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The Validity Analysis between Measurement Method of Subglottic Air Pressure (성문하압 측정방법의 타당도 분석)

  • Park, Sang-Hee;Jeong, Ok-Ran;Seok, Dong-Il
    • Speech Sciences
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    • v.8 no.3
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    • pp.201-208
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    • 2001
  • The purpose of the study was to examine a method most pertinent to measure subglottic air pressure. Subglottic air pressure and loudness analyses were performed on vowels /a/, /i/ and consonant /p/ in 12 normal subjects using. Aerophone II voice function. The experimental contexts were, therefore, /i:pi:pi:/ and /a:pa:pa:/. The subjects produced the intervocalic /p/ in 4 different situations: 1) /i:pi:pi:/ with voiceless /p/, 2) /i:pi:pi:/ with voiced /p/, 3) /a:pa:pa:/ with voiceless /p/, and 4) /a:pa:pa:/ with voiced /p/. A t-test and a correlation analysis revealed the following results. First, when we measured subglottic air pressure by /i:pi:pi:/, voiceless /p/ was significantly different from voiced /p/. Second, when we measured subglottic air pressure by /a:pa:pa:/, voiceless /p/ was significantly different from voiced /p/. Therefore, it was concluded that voiceless /p/ produced more accurate subglottic air pressure and clinicians needed to have patients produce accurate /p/ when measuring subglottic air pressure using Aerophone II.

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Effect of Ginsenosides from Red Ginseng on the Enzymes of Cellular Signal Transduction System (홍삼 사포닌류(Ginsenosides)의 세포 신호 전달계 효소에 미치는 영향)

  • 임경택;최진성
    • Journal of Ginseng Research
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    • v.21 no.1
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    • pp.19-27
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    • 1997
  • The present study was conducted to assess the effect of total saponins from Korean red ginseng on the biosynthesis of inositol phospholipids in vivo and also effects on the metabolic enzymes, such as phosphatidylinositol-specific phospholipase C(Pl-PLC) and PI-kinases. The administration of 0.1% saponin solution, 0.1 ml 3 times a day intraperitoneally to 5 mice for 30 days has increased a 23% of the body weight when it compared with a control group. The amounts of 32P-phoschorus radioactivity incorporated into the phosphoinositides from the liver and brain tissues have increased a 310% and 260%, respectively, in the saponin treated mice. The activities of PI-PLC from liver and brain were stimulated in the various amounts by the conditions treated with saponins. The PI-kinases from liver and brain were also activated by saponins, but its effect was lower than that of PI-PLC. From these results, it was confirmed that red ginseng saponins have affected positively not only on the biosynthesis of phosphoinositides but also on the PI-PLC and PI-kinases related to the cellular signal transduction.

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Apoptosis and Bcl-2 in Astrocytic Tumors (성상교세포종에서 Apoptosis와 Bcl-2 발현)

  • Jang, Yeon Gyoe;Whang, Kum;Hong, Soon-Won
    • Journal of Korean Neurosurgical Society
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    • v.29 no.4
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    • pp.485-490
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    • 2000
  • Objective : To study the expression of apoptosis and bcl-2 in the astrocytic tumors. Patients and Methods : A total of thirty-eight astrocytomas(9 cases in low grade astrocytoma, 12 cases in anaplastic astrocytoma and 17 cases in glioblastoma) are included in this study. Immunohistochemical stain for bcl-2 using monoclonal antibody, in situ end labelling technique for apoptosis were used. Results : The malignant group(anaplastic astrocytoma and glioblastoma) showed significantly higher apoptosis positive index(PI) compared to the benign group(low grade astrocytoma)(1.35 vs 0.14). However apoptosis PI and bcl-2 PI were not significantly different among three groups. Correlation between apoptosis PI and bcl-2 PI was not statistically significant(p=0.58). Conclusion : This result suggest that apoptosis PI and bcl-2 PI are not related the degree of malignancy in astrocytic neoplasm, but apoptosis PI in malignant group was higher possibly due to greater DNA damage.

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$\pi$/4 shift QPSK with Trellis-Code in Rayleigh Fading Channel (레일레이 페이딩 채널에서 Trellis 부호를 적용한 $\pi$/4 shift QPSK)

  • 김종일;이한섭;강창언
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.3 no.2
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    • pp.30-38
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    • 1992
  • In this paper, in order to apply the $\pi$/4 shift QPSK to TCM, we propose the $\pi$/8 shift 8PSK modulation technique and the trellis-coded $\pi$/8 shift 8PSK performing signal set expansion and set partition by phase difference. In addition, the Viterbi decoder with branch metrics of the squared Euclidean distance of the first phase difference as well as the Lth phase difference is introduced in order to improve the bit error rate(BER) performance in differential detection of the trellis-coded $\pi$/8 shift 8 PSK. The proposed Viterbi decoder is conceptually the same as the sliding multiple de- tection by using the branch metric with first and Lth order phase difference. We investigate the performance of the uncoded .pi. /4 shift QPSK and the trellis-coded $\pi$/8 shift 8PSK with or without the Lth phase difference metric in an additive white Gaussian noise (AWGN) and Rayleigh fading channel using the Monte Carlo simulation. The study shows that the $\pi$/4 shift QPSK with the Trellis-code i. e. the trellis-coded $\pi$/8 shift 8PSK is an attractive scheme for power and bandlimited systems and especially, the Viterbi decoder with first and Lth phase difference metrics improves BER performance. Also, the next proposed algorithm can be used in the TC $\pi$/8 shift 8PSK as well as TC MDPSK.

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A National-wide Survey on Utilization of Pattern Identification for Chronic Diseases among Korean Medicine Doctors (전국 한방의료기관 한의사 대상 만성질환의 변증활용 현황 조사)

  • Yeo, Minkyung;Park, Kihyun;Lee, Youngseop
    • Journal of Society of Preventive Korean Medicine
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    • v.21 no.2
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    • pp.23-34
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    • 2017
  • Objectives : The aim of this study was to survey the present utilization of pattern identification(PI) by chronic disease and using PI system in the clinical field among Korean medicine doctors. Methods : This survey was conducted from Oct. 1 to Oct. 31, 2014 by face-to-face interview using structured questionnaire. The subjects were 400 Korean medicine doctors who worked in hospitals or clinics. The questionnaire consisted of whether use clinical experience by chronic disease and the utilization of PI, the utilization of PI systems, the PI utilization rate, and the correlation between utilization PI and so on. General elements consisted of sex, age, clinical experience, place of work, district and so on. Results and Conclusions : This study revealed that clinical experience by chronic disease used 24.0-90.8%. The most chronic diseases were chronic fatigue and chronic pain, and least disease was cancer. Experience of the utilization of PI among Korean medicine doctors who have clinical experience was 87.8-97.1%. Also, the most utilized disease was chronic gastritis & gastric ulcer, and least disease was dyslipidemia. In this case, the most common cases were using the one PI between the utilization of PI systems, and the utilization ratio of Visceral PI was the highest. Phi coefficient between the PI systems in chronic diseases divided into positive correlation and negative correlation. The correlation of dementia between Triple energizer PI and Six excesses PI was the highest at positive correlation, and the frequency of occurrence between Defense, Qi, Nutrient and Blood PI was the highest at positive correlation. The correlation of osteoarthropathy between Meridian and Collateral PI and Sasang Constitutional Medicine was the highest at negative correlation. Also the frequency of occurrence between Qi, Blood, Fluid and Humor PI and Sasang Constitutional Medicine was the highest at negative correlation. We hope that additional studies on systematic PI research of chronic disease which needed to be in korean oriental medicine and meet the needs of clinical consumer continue based on this study.