• Title/Summary/Keyword: pi

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Synthesis and Spectral Properties of 1,2-Bispyrazyl Ethylene (1,2-비스피라질 에틸렌의 합성과 분광학적 성질에 대한 연구)

  • Shim Sang Chul;Lee Dong Soo;Chae, Jeong Seok;Song Pili Soon
    • Journal of the Korean Chemical Society
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    • v.20 no.5
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    • pp.398-405
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    • 1976
  • A new compound, 1,2-bispyrazyl ethylene,is synthesized starting from pyrazine carboxylic acid and methyl pyrazine. The compound is characterized utilizing UV-VIS, IR, NMR and mass spectra along with elemental analysis. Spectroscopic properties are studied from UV-VIS and fluorescence spectra. From unusual salt effects on fluorescence spectra, it is believed that $(n,\;{\pi}^*)$ state has about the same energy as $({\pi},\;{\pi}^*)$ state. The compound fluoresces from $({\pi},\;{\pi}^*)$ state with the quantum yield of 0.025 at $77^{\circ}K$ compared to near unity for stilbene at the same temperature indicating the efficient intersystem crossing to triplet state, because of strong $(n,\;{\pi}^*)$ and $({\pi},\;{\pi}^*)$ mixing in the lowest excited state.

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A National Survey on Utilization of Pattern Identification among Korean Medicine Doctors (전국 한방의료기관 한의사 대상 한의 변증활용 현황 조사)

  • Yeo, Minkyung;Park, Kihyun;Jang, Eunsu;Lee, Youngseop
    • Journal of Society of Preventive Korean Medicine
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    • v.19 no.3
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    • pp.45-55
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    • 2015
  • Objective : The aim of this study was to survey the present utilization of pattern identification(PI) in the clinical field among Korean Medicine Doctors. Method : 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 two sections - a demographics section(i.e., sex, age, clinical experience, place of work, residence and so on) and the main research section(i.e., the PI utilization rate, the utilization of PI systems, the utilization of PI in the clinical domain and in the treatment domain, the correlation between utilization PI and so on). Results : This study revealed that subjects used the PI to 66.7% of their patients on average. The utilization rate of PI in patients was significantly higher for female physicians than for male physicians, for physicians worked in clinics than for physicians who worked in hospitals and for physicians with more than 10 years clinical experience than for physicians with less than 10 years clinical experience. In the utilization of PI systems, Visceral PI was most as 92.0%. There were significant difference on the PI utilization rate according to utilization of Meridian and Collateral PI, Triple Energizer PI, Defense, Qi, Nutrient and Blood PI, Six-Meridian PI and Six Excesses PI. As a result of analysing the PI utilization rate by clinical domain and in the treatment domain, the Treatment and the Drug Treatment showed the highest values. Among utilized PI systems, the correlation coefficients between Defense, Qi, Nutrient and Blood PI and Triple Energizer PI showed the highest value, but the correlation coefficients between Sasang Constitutional Medicine with the each PI showed substantially lower value. Conclusion : The results of this study demonstrate that usage of PI was higher than usage of U code(in KCD) usage in clinical field. we suggested that additional studies on using PI and developing more appropriate standardized tool should be conducted to widen scope of PI's utilization.

Pile Contact Depth Effects in Rubbed Polyimide(PI) Films

  • Kim, Gi-Jeong;Gwon, Hyeok-Min;Lee, Sang-Mun;Lee, Cheol-Gu;Gwak, Mu-Seon;Kim, Bong-Su
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.398-398
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    • 2010
  • To determine the molecular directionality of PI chains depending on rubbing condition, we measured the angle resolved near edge X-ray absorption fine structure (NEXAFS) spectra at C K-edge of the rubbed PI films. Twisted nematic mode PI (PI-TN) and in plane switching mode PI (PI-IPS) were introduced to examine the effect of rubbing conditions on the chain directionality. The average tilt angle a of the PI molecules was estimated through the measured intensity change of $C=C\;{\pi}^*$ in NEXAFS C K-edge spectrum by controlling the stage speed and the pile contact depth. After rubbing, the irregular molecular direction changed to a regular direction with a molecular tilt angle of $51.2^{\circ}$ for PI-TN and $49.6^{\circ}$ for PI-IPS at the rubbing condition of the roll speed of 1000 rpm, stage speed of 50 mm/sec, and file contact depth of 0.3 mm. The molecular tilt angle $\alpha$ was linearly decreased in the PI-TN and PI-IPS samples with increasing depth of the pile contact.

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Efficient method of Searching PI Code on RDS System (RDS System 에서의 효율적인 PI code 검출 기법에 관한 연구)

  • Cho, Chung-bum;Kim, Yound-cil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.112-115
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    • 2009
  • PI code searching method of RDS(Radio Data System) are unique method of maintain desired channel on moving machine like vehicle. Efficient and fast PI code search method are researching on the all of RDS related systems for both find more better channel before Original channel signal go to bad and find desired good signal quickly when get out of Weak signal Area. But Embedded system has limited environment like memory size, so It is very difficult to apply many well known PI code searching method. This thesis suggests simple and effective method of searching PI code, considering a Embedded System Environment.

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Studies on HG Type of Heterodera glycines in Korea (국내 콩 씨스트선충의 HG type 분석)

  • Kim, Donggeun;Choi, Insoo;Han, Wonyoung;Ryu, Younghyun;Kim, Myungsik;Bae, Changhwan
    • Research in Plant Disease
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    • v.19 no.1
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    • pp.31-35
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    • 2013
  • Thirteen soybean cyst nematode (SCN) (Heterodera glycines) populations collected in Korea were examined in their HG type by their reproductivity on 7 Plant Introduction indicators for the identification of HG type. Six HG types were identified, HG type 0, 2, 5, 2.5, 1.2.7, and 2.5.7. HG type 2.5 was the most frequent (4 samples, 30.8%), followed by HG type 2.5.7 (3 samples, 23.0%). About 76.9% of SCN populations were reproduced on PI 88788, followed by PI 209332 (61.5%), PI 548316 ('Cloud') (30.8%), and PI 548402 ('Peking') (7.7%). No population could reproduce on PI 90763, PI 437654, thus, they could be used for resistant source for developing SCN resistant soybean in Korea.

Spectroscopic Studies of trans-1,2-Bispyrazylethylene (트란스-1,2-비스피라질에틸렌에 대한 분광학적 연구)

  • Sang Chul Shim;Han-Young Kang
    • Journal of the Korean Chemical Society
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    • v.22 no.4
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    • pp.239-244
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    • 1978
  • Spectroscopic studies of trans-1,2-bispyrazylethylene (BPE), one of the stilbene analogues, were carried out. In normal UV spectra, a distinct $n{\rightarrow}{\pi}^*$ absorption band is missing because of a strong, nearly isoenergetic ${\pi}{\rightarrow}{\pi}^*$ absorption band. The second derivative and low temperature $(77^{\circ}K)$ UV absorption spectra were taken and $n{\rightarrow}{\pi}^*$ absorption band was identified by these methods. The transition energies of ${\pi}{\rightarrow}{\pi}^*$ transitions were calculated by Pariser-Parr-Pople (PPP)-SCF-CI MO method. The calculated values showed good agreement with the observed spectral data. Luminescence studies were also carried out at low temperature. From the fluorescence spectra, fluorescence polarization studies, and PPP-SCF-CI MO calculation, the fluorescent state was determined to be a singlet $({\pi},\;{\pi}^*)$ state. This conclusion is in good agreement with the results obtained from alkaline salt effects on the fluorescence of this compound.

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Similitude Study on Grain Thrower (차원해석방법에 의한 Thrower의 양곡특성에 관한 연구)

  • 김만수;정창주
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.16 no.4
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    • pp.3572-3584
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    • 1974
  • 본 논문은 Thrower의 양곡성능에 관한 예측 방정식을 차원해석법을 적용하여 유도하는데 있다. Thrower의 능률에 큰 영향을 미친다고 생각되는 인자들간의 관계식들을 Buckingham의 $\pi$이론에 의하여 구하여 졌으며 본연구에 사용한 Thrower는 현재 농촌에서 사용되고 있는 자동탈곡기의 Thrower와 유사한 형으로 제작된 것이며 실험에 사용된 시료는 벼의 경우는 통일벼와 미네히까리 품종이고 보리 품종으로서는 나맥이며, Thrower의 Impeller 직경, 속도 및 투입량을 변화시켜 가면서 각 시료에 대하여 양곡높이를 측정하여 그 예측방정식을 유도하였다. 본 논문에서 얻은 결과는 다음과 같다. 1. Thrower의 양곡성능에 지대한 영향을 미친다고 생각되는 주요 인자들을 Thrower의 양정, impeller의 직경과 속도, 투입량, 곡립의 밀도, 중력가속도등이라 간주하여 Buckingham의 $\pi$이론을 적용하여 이들에 관한 $\pi$항들을 결정하였으며 그 결과는 다음과 같다. {{{{ pi 1= { D} over {H } , pi 2= { { DN}^{ { 1} over {2 } } } over { { g}^{ { 1} over { 2} } }, pi 3= { Q} over { { g}^{ { 1} over {2 } } { rho D}^{ { 2} over {6 } } }}}}} 2. 실험에 의하여 구해진 $\pi$항문의 관계식을 합성하여 Thrower의 양곡성능에 관한 시료별 예측방정식을 구하였으며 이 식들은 아래와 같다. 통일 : $\pi$1=0.1223($\pi$2)-1.1813$\times$($\pi$3)-0.1864 미네히까리 : $\pi$1=0.1185($\pi$2)-0.9663$\times$($\pi$3)-0.1575 나맥 : $\pi$1=0.1599($\pi$2)-1.2350$\times$($\pi$3)-0.1382 3. 현재 농촌에서 사용되고 있는 자동탈곡기체 부착된 Thrower의 회전수, Impeller의 직경 및 투입량은 각각 1,100rpm, 30cm 및 150gr/sec 정도로서 이와같은 수준의 변량들을 기초로 하여 본 논문에서 유도한 예측방정식을 적용하여 Thrower의 양정을 산출한 결과, 통일벼의 경우는 2.6m정도였고 미네히까리 품종과 나맥의 양정은 각각 2.4m, 2.9m 정도였다. 이와같은 사실로부터 1m내외의 양정만으로 되어있는 자동탈곡기 Thrower의 경우 제작비절감, 소요동력 감소를 기하고 아울러 과립의 손상을 줄이기 위해서는 설계 또는 작동조건의 변경을 통해 Thrower의 회전수를 현재 수준이하로 줄일 필요가 있다고 판단되었다.

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$\pi$/4 shift QPSK with Trellis-Code and Lth Phase Different Metrics (Trellis 부호와 L번째 위상차 메트릭(metrics)을 갖는$\pi$/4 shift QPSK)

  • 김종일;강창언
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.10
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    • pp.1147-1156
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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 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 different is introduced in order to improve the bit error rate(BER) performance in differential detection of the trellis-coded $\pi/8$ shift 8PSK. The proposed Viterbi decoder is conceptually the same as the sliding multiple detection 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) 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 nest proposed algorithm can be used in the TC $\pi/8$ shift 8PSK as well as TCMDPSK.

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ON πgs-CLOSED SETS IN TOPOLOGICAL SPACES

  • LEE, BU YOUNG;SHIN, SU-YOUNG;PARK, JIN HAN
    • Honam Mathematical Journal
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    • v.28 no.2
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    • pp.261-277
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    • 2006
  • In this paper a new class of sets called ${\pi}gs$-closed sets is introduced and its properties are studied. Further the notions of ${\pi}gs$-$T_{1/2}$ spaces and ${\pi}gs$-continuity are introduced.

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