• Title/Summary/Keyword: phase shifts

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Phase Shifts of Bound State Waves Scattered at Classical Turning Points: Morse Potential

  • Sun, Ho-Sung
    • Bulletin of the Korean Chemical Society
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    • v.26 no.11
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    • pp.1717-1722
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    • 2005
  • The analytical transfer matrix method suggests a new quantization condition for calculating bound state eigenenergies exactly. In the quantization condition, the phase shifts of bound state wave functions scattered at classical turning points are explicitly introduced. We calculate the phase shifts of eigenfunctions of the Morse potential with various boundary conditions in order to understand the physical meaning of phase shifts. The Morse potential is known to adequately describe the interaction energy between two atoms and, therefore, it is frequently used to determine the vibrational energy levels of diatomic molecules. The variation of Morse potential eigenenergies influenced upon by changing boundary conditions is also investigated.

Algorithm for The Relative Phase Shifts between PN Sequences Generated by 90/150 Cellular Automata (90/150 셀룰라 오토마타에 의해 생성되는 PN 수열들 사이의 상대적 위상이동차에 대한 알고리즘)

  • Cho, Sung-Jin;Choi, Un-Sook;Kim, Han-Doo
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.15 no.4
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    • pp.3-10
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    • 2005
  • Every cell position of a maximum-length 90/150 cellular automata(CA) generates the same pseudo-noise(PN) sequence corresponding to the characteristic polynomial of the CA with a phase shift. Unlike LFSRs, the phase shift is generally different between stages of a CA. In this paper, we propose an algorithm to compute relative phase shifts between stage of a CA. Our algorithm does not need Shank's algorithm to compute relative phase shifts and does not need any previous phase shifts to compute a phase shift. Moreover it is done in time $O(2^n)$.

Pigment-dispersing factor induces phase shifts of circadian locomotor rhythm in the cricket Gryllus bimaculatus

  • Singaravel, Muniyandi;Tomioka, Kenji
    • Journal of Photoscience
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    • v.9 no.2
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    • pp.243-245
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    • 2002
  • Pigment-dispersing factor (PDF) is an octadecapeptide distributed in the optic lobe and the brain in a variety of insect species. There are lines of evidence suggesting possible involvement of PDF in the insect circadian system. However, its physiological roles in the circadian time keeping mechanism have not been clearly defined. In this study, we have examined the phase shifting effects of Gryllus-PDF on the circadian locomotor rhythm in the cricket Gryllus bimaculatus of which circadian clock is located in the optic lobe. Phase shifts in the circadian activity rhythm were measured following microinjection of 22nl of vehicle (Ringer's solution) or O.lmM PDF into the optic lobe through the compound eye at various circadian times. The results showed that PDF induced phase shifts of the circadian clock in a phase-dependent manner, suggesting that it may play a role as an input signal for the circadian clock.

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Analysis of Shrinking Generator Using Phase Shifts (위상이동차를 이용한 수축 생성기의 분석)

  • Hwang, Yoon-Hee;Cho, Sung-Jin;Choi, Un-Sook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.11
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    • pp.2507-2513
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    • 2010
  • In this paper, we show that the shrinking generator with two LFSR whose characteristic polynomials are primitive is an interleaving generator and analyze phase shifts in shrunken sequence. Also for a given intercepted sequence of shrunken sequence, we propose. the method of reconstructing some deterministic bits of the shrunken sequence using phase shifts.

Phase-Shifted Fiber Bragg Grating Transmission Filters Based on the Fabry-Perot Effect

  • Liu, Y.u;Lee, S. B.;Choi, S. S.
    • Journal of the Optical Society of Korea
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    • v.2 no.1
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    • pp.30-33
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    • 1998
  • We present the analysis of phase-shifted fiber Bragg gratings by coupled-mode equations. The transmission is expressed as that of a Fabry-Perot resonator with complex reflectance and complex transmittance. The transmission spectrum, the effective cavity length, and the behaviors with different phase-shifts are investigated. A very flattered transmission peak is obtained by introducing three phase-shifts in a grating.

Measurement of three dimensional shapes using phase-shifting shadow moire method (위상 이동 그림자 무아레 방법을 이용한 3차원 형상의 측정)

  • 강영준
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.6 no.4
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    • pp.39-45
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    • 1997
  • Shadow moire topography has been used as a noncontact method for measuring the 3-D shapes of objects. The moire fringes are results from the superposition of a master grating and its shadow projected on the surface of an object. But in case of the classical shadow moire method, in general, the resolution is a few tenths of millimeter. It is difficult to use a phase -shifting method in shadow moire because it is impossible to obtain uniform phase shifts on the whole field. But in this study , We introduce a phase-shifting method to improve the resolution of the classical shadow moire method. This method is based on the fact that if the depth of object is much less than the distance between the observer and the master grating, the phase shifts are almost uniform on the whole field area. Finally, we applied this new phase-shifting method to the measurement of the 3-D shape of a coin.

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Measurement of three dimensional object shape by means of the phase-shifting shadow moire (위상이동 그림자 무아레법을 이용한 3차원 물체의 형상측정)

  • 유원재;노경완;강영준
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.04a
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    • pp.96-100
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    • 1997
  • The shadow moire is one of the optical techniques which is able to give contour lines of an object with respect to a master grating plane. The moire patterns are issued from the superposition of a master grating and its shadow projected on the surface of an object. In case of the classical shadow moire method, the sensitivity was a few tenths millimeters. generally, it is difficult to use a phase shift method in shadow moire because it is impossible to obtain uniform phase shifts on the whole field. But in this study we use the fact that if the depth of object is much less than the distance between the observer and the master grating, and the object is displaced perpendicularly to the grating plane, phase shifts are almost uniform. Finally we obtained a better resolution by using a phase shift procedure and applied the phase shifting shadow moire to three dimensional shape measurement.

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A Statistical Study of Effective Properties due to Fiber Tow Misalignment and Thickness Change for Plain Weave Textile Composites (섬유다발 배열 및 적층수에 따른 평직복합재료 등가물성치의 변화에 관한 통계적 연구)

  • 우경식;서영욱
    • Composites Research
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    • v.13 no.6
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    • pp.63-72
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    • 2000
  • In this paper, statistical treatments of effective properties for plain weave textile composites were presented. Configurations up to 32 layers with varied stacking phase shifts were considered. Effective properties were calculated by numerical simulation in which uni-axial tensile and shear load were applied at unit cell. Sample analysis was utilized to consider the inherent randomness in the phase shift and the results were treated statistically. It was found that effective properties were dependent on stacking phase shifts for thin plain weave textile composites. The distribution of $E_{xx}$ and $V_{xy}$ were skewed and the range of possible values was relatively large. As the number of layers increased, however, the distribution width became narrower and mean values converged. In contrast, $G_{xy}$ was not affected by phase shifts and thickness changes.

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The Effect of Shift Directions of Clinical Nurses on the Circadian Rhythm (임상 간호사의 교대근무 방향아 circadian rhythm 변화에 미치는 영향)

  • Hwang Ae-Ran;Chung Hyun-Sook;Kang Kyu-Sook;Lee Kyu-Jung
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.1 no.1
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    • pp.77-97
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    • 1994
  • The circadian system represents a temporal order which is mediated by the mutual coupling of oscillators and by the synchronizing effects of zeitgebers. It is known that well-being of man depends partly on the maintenance of this order, and that repeated or long lasting disturbances to it such as shift work will Cause harmful effects. This study was a quasi-experimental study to test the effect of shift directions for the clinical nurses on the circadian rhythm. Fourteen nurses working at the general units of Y hospital were selected according to the established criteria. Fourteen subjects were assigned to a weekly shift but the directions of shift work were phase delay first and then phase advance or vice versa. Oral temperature, total sleeping time, frequency of sleep-wake cycle, fatigue, mental performance, and physical symptom were measured during these days except holidays. The data collection period was from April 26, 1993 to July 3, 1993. MANOVA and Wilcoxon signed rank test were used for statistical analysis. The results are summarized as follows. 1. Having worked on evening and night shifts in either phase delay or phase advance schedules, temperature rhythms of shift workers were gradually adapted to the new sleep-wake cycles. A complete adaptation to work on the night shift was achieved the sixth day of the night shift in the phase delay schedule compared to the partial adaptation to the work on the night shift in the phase advance schedule. Accordingly, by putting evening shift between day and night shifts, it will be possible for circadian rhythm to adapt easily to the night shift. 2. There were differences in the total sleeping time, frequency of steep-wake cycle, fatigue, and physical symptom except for mental performance between night shift and day, evening shift. This indicates further that shift workers working on the night shift have a hard time adapting to the shift work compared to the other shifts. 3. Evaluating all the acrophases of temperature rhythm either in phase delay or phase ad-vance schedules, it was shown that night to evening shift in the phase ad-vance schedule revealed the smallest phase move. Also phase advance schedule showed poorer adaptation to shift work than phase delay schedule in connection with total sleeping time, frequency of sleep-wake cycle, fatigue, mental performance, and physical symptom. It is suggested, taken together, these findings reflect that phase delay schedule facilitated the degree of adjustment to the shift work compared to the phase advance schedule.

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Investigation on structural symmetry of CsCoCl3·2H2O crystals by magic-angle spinning 1H and static 133Cs nuclear magnetic resonance

  • Park, Sang Hyeon;Jang, Du Chang;Jeon, Hara;Gyeong, Oh Yi;Lim, Ae Ran
    • Journal of the Korean Magnetic Resonance Society
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    • v.26 no.1
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    • pp.10-16
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    • 2022
  • The phase transition temperatures of CsCoCl3·2H2O crystals are investigated via differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Three endothermic peaks at temperatures of 370 K (=TC1), 390 K (=TC2), and 416 K (=TC3) were observed for phase transitions from CsCoCl3·2H2O to CsCoCl3·1.5H2O, to CsCoCl3·H2O, and then to CsCoCl3·0.5H2O, respectively. In addition, the spin-lattice relaxation time T in the rotating frame and T1 in the laboratory frame as well as changes in chemical shifts for 1H and 133Cs near TC1 were found to be temperature dependent. Our analyses results indicated that the changes of chemical shifts, T, and T1 are associated with structural phase transitions near temperature TC1. The changes of chemical shifts, T, and T1 near TC1 were associated with structural phase transitions, owing to the changes in the symmetry of the structure formed of H2O and Cs+ ions. Consequently, the structural symmetry in CsCoCl3·2H2O crystals based on temperature is discussed by the environments of their H and Cs nuclei.