• Journal of Power Electronics
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• v.9 no.2
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• pp.146-155
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• 2009

The static frequency converter (SFC) systems are used as a method of driving large synchronous machines in many power and industrial plants. In this paper, new control algorithms of SFC systems for starting gas turbo sets are proposed for a four quadrant operation: start-up at standstill; an acceleration up to the speed of the rated voltage; field weakening to reach the rated speed; synchronization to the main alternating current (AC) source; and dynamic braking to stop safely within the rating of the synchronous machine. Experimental results show that the proposed algorithms are proper and effective.

• Development and Reproduction
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• v.21 no.1
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• pp.47-54
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• 2017

Unlike mouse results, cloning efficiency of nuclear transfer from porcine induced pluripotent stem cells (piPSCs) is very low. The present study was performed to investigate the effect of cell cycle inhibitors on the cell cycle synchronization of piPSCs. piPSCs were generated using combination of six human transcriptional factors under stem cell culture condition. To examine the efficiency of cell cycle synchronization, piPSCs were cultured on a matrigel coated plate with stem cell media and they were treated with staurosporine (STA, 20 nM), daidzein (DAI, $100{\mu}M$), roscovitine (ROSC, $10{\mu}M$), or olomoucine (OLO, $200{\mu}M$) for 12 h. Flow Cytometry (FACs) data showed that piPSCs in control were in G1 ($37.5{\pm}0.2%$), S ($34.0{\pm}0.6%$) and G2/M ($28.5{\pm}0.4%$). The proportion of cells at G1 in DAI group was significantly higher than that in control, while STA, ROSC and OLO treatments could not block the cell cycle of piPSCs. Both of viability and apoptosis were affected by STA and ROSC treatment, but there were no significantly differences between control and DAI groups. Real-Time qPCR and FACs results revealed that DAI treatment did not affect the expression of pluripotent gene, Oct4. In case of OLO, it did not affect both of viability and apoptosis, but Oct4 expression was significantly decreased. Our results suggest that DAI could be used for synchronizing piPSCs at G1 stage and has any deleterious effect on survival and pluripotency sustaining of piPSCs.

• Journal of Music and Human Behavior
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• v.16 no.1
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• pp.47-72
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• 2019

This study reviewed and analyzed English-written studies using a rhythmic tapping task for motor control of children with autism spectrum disorder (ASD). Inclusion criteria for the participants were children with ASD and typically developing (TD) children. The keywords used for the outcome variables included rhythmic tapping, timed movement, and synchronization. Ten studies were included in the final analysis. The included studies were analyzed in terms of target variables, auditory stimuli, and measurements. A meta-analysis was also conducted to examine how children with ASD performed rhythmic tapping tasks compared to children with TD. In the identified studies, five variables were used: timed movement control, timing reproduction, bimanual coordination, synchronization, and interpersonal synchronization. It was found that rhythmic tapping performance was analyzed in terms of accuracy and precision of the movement and reported as significantly correlated to social skills measures. The meta-analysis results showed that there were no significant differences between the ASD and TD groups in continuing rhythmic movements when the presented auditory stimuli ended, whereas there were significant group differences in their ability to maintain their motor performance consistently and to synchronize with auditory cue or with others. These results support the rhythmic tapping task as an effective measure for not only motor control but also social skills development in children with ASD.

• The Journal of the Korea Contents Association
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• v.11 no.11
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• pp.194-203
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• 2011

This study investigated the effectiveness of visual biofeedback simulation training for patients with incomplete spinal cord injuries. Fifteen people with an ASIA impairment scale of C and D, according to the intervention method, were studied. They were randomly divided into two groups, seven people in the experimental group and eight people in the control group. They were studied three times a week for six weeks using a Tetrax Interactive Balance System, for a total of eighteen times, and each test took fifteen minutes. Paired t-tests were used to evaluate the changes before and after intervention. The difference between the groups was compared using an independent t-test. The experimental group showed significantly increased general stability, fall risk index, weight distribution (A, C, D, LEFT, HEEL) and weight distribution index, except for synchronization AC, BD. However, the control group only showed significantly increased weight distribution (A, C, LEFT). In a variation, experimental and control groups showed significantly increased weight distribution (A, B, C, HEEL), general stability, fall risk index and synchronization AD. Consequently, it was found that visual biofeedback simulation training was effective for the balance ability of incomplete spinal cord injury patients, and further studies are required.

• Journal of electromagnetic engineering and science
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• v.4 no.2
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• pp.72-78
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• 2004

In this paper, we evaluate the performance of the digital modulation schemes described in the APCO Project 25 FDMA specifications which can be used for applying the ultra-narrowband technology to the current domestic simple two-way radio systems, and discuss difficulties in the DSP implementation of the systems. We analyze the effect on the systems' BER performance of receiver non-matched filter and frequency-offset between the transmitter and receiver oscillators. And we present a frequency offset compensation method for improving the system performance. The results of performance analysis showed that the CQPSK of APCO Project 25 using non-matched filter degraded the BER by 0.5～1.0 ㏈ comparing with PI/4 DQPSK using matched filter. In the event of 2 % frequency offset, about 1 ㏈ performance loss was produced at the BER of $$10^{-3}TEX>. With the frequency-offset compensation method implemented in the systems using phase recovery scheme of PSK synchronization detection, the performance degradation of about 1.0 ㏈ was occurred at the BER of $$10^{-3}TEX> for 10 % of frequency offset. The proposed method can be used for the improvement of system performance.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.140-140
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• 2003

The study evaluated the effect of donor cell treatments for G0/Gl synchronization and the donor ceil type on development and incidence of apoptosis in cloned cattle embryos. Primary cultures were established from a female fetus on day 50 of gestation and adult ear skin biopsies. Cells were randomly allocated into 3 experimental treatment groups after 6~8 passages. Group 1 (Confluent), cells were cultured in DMEM supplemented with 10% FBS until 90% confluent. Group 2 (Serum-starvation), cells were cultured in DMEM Supplemented With 0.5% FBS for 5 days. Group 3 (Roscovitine), Cells were cultured in DMEM supplemented with 10% FBS and 30 $\mu$M Roscovitine for 12 h. Cell cycle and apoptosis were analyzed using flow cytometry after labelling with DAPI and YO-PRO-1. At 19 h post-maturation (hpm), enucleated oocytes were reconstructed with donor cells and fused by a single DC pulse (1.6 kV/cm, 60 $\mu$sec). (중략)

• Clinical and Experimental Reproductive Medicine
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• v.48 no.4
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• pp.352-361
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• 2021

Objective: The study assessed the developmental potential of germinal vesicle (GV) oocytes subjected to in vitro maturation (IVM) after prematuration culture with cilostamide (a phosphodiesterase-3 inhibitor) and the impact of cilostamide exposure on the morphology of meiosis II (MII) oocytes and subsequent embryo quality. Methods: In total, 994 oocytes were collected from 63 patients. Among 307 GV oocytes, 140 oocytes were selected for the experimental group and 130 oocytes for the control group. The denuded GV-stage oocytes were cultured for 6 hours with cilostamide in the experimental group and without cilostamide in the control group. After 6 hours, the oocytes in the experimental group were washed and transferred to fresh IVM medium. The maturational status of the oocytes in both groups was examined at 26, 36, and 48 hours. Fertilization was assessed at 18 hours post-intracytoplasmic sperm injection. Embryo quality was assessed on days 3 and 5. Results: In total, 92.1% of the oocytes remained in the GV stage, while 6.4% converted to the MI stage (p<0.01) after cilostamide exposure. In both groups, more MII oocytes were observed at 36 hours (25.8% vs. 21.5%) than at 26 hours (10.8% vs. 14.6%) and 48 hours (13% vs. 7.9%) (p>0.05). With the advent of cilostamide, blastocyst quality was better in the experimental group than in the control group (p<0.05). Conclusion: Cilostamide effectively blocked nuclear maturation and promoted cytoplasmic growth. Prematuration culture with cilostamide enabled synchronization between cytoplasmic and nuclear maturity, resulting in better blastocyst outcomes.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.3
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• pp.245-255
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• 2023

Time comparison techniques are necessary for generating and keeping Coordinated Universal Time (UTC) and distributing standard time clocks. Global Navigation Satellite System (GNSS) Common View, GNSS All-in-View, Two-Way Satellite Time and Frequency Transfer (TWSTFT), Very Long Baseline Interferometry (VLBI), optical fiber, and Network Time Protocol (NTP) based methods have been used for time comparison. In these methods, GNSS based time comparison techniques are widely used for time synchronization in critical national infrastructures and in common areas of application such as finance, military, and wireless communication. However, GNSS-based time comparison techniques are vulnerable to jamming or interference environments and it is difficult to respond to GNSS signal disconnection according to the international situation. In response, in this paper, Code-Division Multiple Access (CDMA) based All-to-All TWSTFT operation method is proposed. A software-based simulation platform also was designed for performance analysis in multi-TWSTFT signal environments. Furthermore, code and carrier measurement jitters were calculated in multi-signal environments using the designed simulation platform. By using the technique proposed in this paper, it is anticipated that the TWSTFT-based time comparison method will be used in various fields and satisfy high-performance requirements such as those of a GNSS master station and power plant network reference station.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.10
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• pp.1365-1371
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• 2011

The intensity and duration of sexual behavior in Bos indicus was assessed through the continuous observation of sexual receptivity. Two groups of cows were formed: only synchronized (n = 50) and other group further superovulated (n = 20). An intravaginal implant that released progesterone over 9 d was used. After removing the implant, 25 mg of $PGF_{2{\alpha}}$ was administered. In the superovulated group, the administration of 280 mg (Follicle stimulant hormone) FSH-P1 per cow with a decreasing dosage over 4 d was utilized. In both groups, behavioral observations began at the moment of implant removal. Sexual behavior was analyzed using a Kruskal-Wallis test to compare the mean of hours in estrus, effective mountings and number of mounts/hour during estrus. A nonparametric survival analysis was performed using the time in two ways: i) when an event happened it was placed in a 24 h timeframe and, ii) the time of observation in continuous form (96 h) assessing the difference between curves by the log rank test Chi-square. The only significant difference was the number of mounts/h during receptivity (p<0.05). In the superovulated group three periods of sexual activity during the day were identified, with these events being of greater frequency and duration than the synchronized group (p = 0.02); besides, the superovulated group began estrus before the synchronized group (p = 0.0035) when using the total period. In a simulation study, when the number of observations went from two (06:00-18:00) to three periods (06:00, 12:00 and 18:00) cows detected accurately (<6 h after the onset) increased more than 20%. The results show that superovulated cows presented greater intensity and duration of sexual activity in contrast with only synchronized animals.