• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.5A
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• pp.290-297
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• 2012

In this paper, we proposed new modulation schemes, Offset Phase Rotation Shift Keying (OPRSK) and Phase Shift Rotation Shift Keying (PSRSK), for medical in-body wireless body area network (WBAN) systems. In IEEE, the WBAN system is assigned as 802.15. Task Group (TG) 6, and the related standardization is being progressed. Recently, in this Group, Phase Silence Shift Keying (PSSK), Phase Silence Position Keying (PSPK) and Phase Rotation Shift Keying (PRSK), which can obtain higher power efficiency, are proposed as new modulation schemes for low-power operation of WBAN system. However, they have a disadvantage for non-linear amplifier distortion. Therefore, in this paper, we proposed OPRSK and PSRSK, which are robust to non-linear amplification, by employing a phase offset in constellation and a power distribution in symbol duration, and verified that the proposed methods have good perfomance and stable operation through performance evaluation.

• 전기의세계
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• v.27 no.6
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• pp.63-68
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• 1978

To convert into multiphase from single phase are often necessary for industry field. In oder to convert of phase, phase shifted voltages are first buileded by single phase and then must combine with these voltages adequately. This paper aims at the description of the way of phase shift by means of turning on or turning off through natural commutation and forced commutation methods with firing angle of thyristor pating a role of switching controlled adequately. Experimental result of the Phase Shift with the Thyristors Utilized has been turned out to shift the phase to 60.deg., 90.deg., 120.deg., and other angles.

• 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.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.4
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• pp.484-492
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• 2015

This paper proposes a PWM phase-shift circuit to make that the LED lighting system distributes the channel currents evenly for any number of LED strings by generating evenly phase-shifted PWM signals for multiple LED driver ICs. The evenly distributed channel currents reduce the peak current, the decoupling capacitor size, and EMI noise. The PWM phase-shift circuit makes an arbitrary degree of PWM phase-shift by using a resistor and a capacitor. It measures the RC delay once. It reduces the number of external resistors and capacitors by providing zero and 180 degree phase-shift modes requiring no resistor and capacitor. An LED driver IC with the PWM phase-shift circuit was fabricated with a $0.35{\mu}m$ BCDMOS process. The PWM phase-shift circuit receives a PWM signal of 50 Hz~20 kHz at $f_{CLK}=450kHz$ and it generates a $0{\sim}360^{\circ}$ phase-shifted PWM signal with $R=0{\sim}1.1M{\Omega}$ at C=1 nF and $f_{PWM}=1kHz$. The measured phase errors are 1.74~3.94% due to parasitic capacitances.

• International journal of advanced smart convergence
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• v.11 no.3
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• pp.17-22
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• 2022

As the sixth generation (6G) promising technique, intelligent reflecting surface (IRS) has recently attracted much attention. The IRS based wireless communication is expected to deploy the upcoming 6G mobile networks, to increase energy and spectrum efficiency in the fifth generation (5G) wireless networks. In this paper, we compare the bit-error rate (BER) performances for phase-shift schemes of IRS non-orthogonal multiple access (NOMA). First, we derive a BER expression for the equalizing phase-shift scheme in IRS-NOMA networks. Then we compare the BER of the equalizing phase-shift scheme to that of the identical phase-shift scheme in IRS-NOMA networks, and show the BER improvement of the equalizing phase-shift scheme IRS NOMA over the identical phase-shift scheme IRS NOMA. Furthermore, we also validate the proposed analytical BER for the equalizing phase-shift scheme in IRS-NOMA by Monte Carlo simulations, and demonstrate that they well match each other.

• 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.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.9
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• pp.1-6
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• 1997

A transmission type phase shift attenuator has a poor reflection characteristics at an output port. And that is controlled by the current, its dynamic rnage decreases due to the current limitation. In this paper, to avoid such disadvantages, a reflection type low phase shift attenuator has been designed and measured. As a result, at a center frequency (1855MHz), the sreflection type low pahse shift attenuator has an attenuation of 30dB, within the limit of 3 phase shift and less than -17dB reflection characteristics at both input and output ports. And it demonstrates the peformance of the reflection type low phase shift attenuator is better than the transmission type phase shift attenuator with the same measurement specifications.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.8
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• pp.861-866
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• 2014

This study evaluates the modeling accuracy of the existing three phase shift models on which the time domain oscillator phase noise theories are based. For the evaluation, this study investigates how accurately the three models can model the phase shift impulse train response of a simple planar oscillator. Evaluation result reveals that Kaertner model most accurately reflects the oscillator's phase shift impulse train responses for five different impulse train inputs, whereas PP model exhibited the worst performance in modeling the phase shift impulse train responses.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.5
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• pp.644-651
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• 2009

In this paper, the design results of a $22.5^{\circ}$ diode phase shifter for the RADANT lens and two $11.25^{\circ}$, $22.5^{\circ}$ dielectric phase shift layers for the diode phase shifter are presented. The amount of phase shift introduced by each dielectric layer depends on the thickness and the shape of the metal strip and the electrical property of the diode. The equivalent circuit model is employed to represent the dielectric phase shift layer, and the simulated result of the equival circuit model is compared with the result of the field simulation. The measured data of the fabricated $11.25^{\circ}$, $22.5^{\circ}$ dielectric phase shift layer shows about $2^{\circ}$ phase shift error.

• New Physics: Sae Mulli
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• v.68 no.12
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• pp.1331-1337
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• 2018

We present a three-parameter phase shift model whose form is the same as that of Coulombmodified Glauber model obtained from Gaussian nuclear densities. This model is applied to the $^6Li+^{12}C$ and the $^6Li+^{28}Si$ elastic scatterings at $E_{lab}=318MeV$. The calculated differential cross sections provide quite a satisfactory account of the experimental data. The diffractive oscillatory structures observed at forward angles can be explained as being due to the strong interference between the near-side and the far-side scattering amplitudes. The optical potentials for two systems are predicted by using the method of inversion. The calculated inversion potentials are found to be in fairly good agreements with the results determined from the optical model analysis in the surface regions around the strong absorption radius. We also investigate the effects of parameters in the three-parameter phase shift model on the elastic scattering cross sections.