• Title/Summary/Keyword: band power

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Korea's Street Processions and Traditional Performing Arts (한국의 가두행렬(街頭行列)과 전통연희)

  • Jeon, KyungWook
    • (The) Research of the performance art and culture
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    • no.18
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    • pp.513-557
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    • 2009
  • The procession depicted in Goguryeo's ancient tomb mural consists of guards, honor guards, music band, and performing artists. Since this coincides with the royal processions of Goryeo and Joseon Dynasties, the relationship of its impact can be examined. The performing arts appearing in such street procession were mostly sanakbaekhui. During the Goryeo Dynasty, the king visited Bongeunsa templ when the lotus lantern festival was celebrated. At such time, on the left and right sides of the road travelled by the king were installed mountains made of lanterns and trees made of lanterns. The procession was quite large in scale and was accompanied by colorful music and performances. In the narye ceremony of the Goryeo Dynasty, as in China, street procession and performing arts took place. The jisinbarbgi performed by a peasant band in early January is a custom of narye. A new character appears in the royal narye during the first half of the Joseon period. Therefore the features of narye transforming according to the changes of the times can be examined. In the Joseon Dynasty's procession of a king returning to the palace, the royal band in front and behind the carriage of the king played marching music, and led by a sanbung this street procession headed toward the palace. Various performances also took place during this time. The samilyuga and munhuiyeon were festivals of the yangban class(nobility). Those who passed the state examination hired musicians and performers and paraded around town in Seoul for three days to celebrate the auspicious outcome for their family and to show off their family's power. In the Joseon's dongje and eupchijeui ceremonies, street processions were carried out with a shrine deity image or symbolic flag at the head. The dongje in a Korean village, combined with jisinbarbgi, incorporated a procession with the flags ymbolizing the guardian deity of the village at the head, and this went from house to house. The procession of suyeongyaru had the publicity impact of a mask play performance, and by creating a sense of unity among the participants, heightened the celebratory atmosphere. At the core of the bukcheonggun toseongri gwanweonnori was as treet procession imitating the traveling of high government officials. The toseong gwanweonnori has the folk religion function of praying for safe human living and abundance of grains for the village, the entertainment function of having fun and joy through street processions and various performances, and the social function of creating unity and harmony among the residents. In all the aforementioned events, the street procession had a large role in creating a celebratory atmosphere, and the performance of traditional performing arts in the middle of the procession or after the procession enabled the participants to feel united. The participants of the street procession felt cultural pride and self-confidence through the various events and they were able to have the opportunity to show off and proudly display their abilities.

Characteristic Study of Small-sized and Planer Resonator for Mobile Device in Magnetic Wireless Power Transfer (소형 모바일 기기용 공진형 무선전력전송 시스템의 공진기 평면화 및 소형화에 따른 특성 연구)

  • Lee, Hoon-Hee;Jung, Chang-Won
    • Journal of the Institute of Electronics and Information Engineers
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    • v.54 no.4
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    • pp.16-21
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    • 2017
  • In this paper, a Small-sized and planer resonator design of Magnetic Resonance - Wireless Power Transfer(MR-WPT) were proposed for practical applications of mobile devices, such as a laptop, a smart-phone and a tablet pc. The proposed MR-WPT system were based on four coil MR-WPT and designed as a transmitter part (Tx) and a receiver part (Rx) both are the same shape with the same loop and resonator. There are four different spiral coil type of resonators with variable of line length, width, gap and turns in $50mm{\times}50mm$ size. The both of top and bottom side of substrate(acrylic; ${\varepsilon}_r=2.56$, tan ${\delta}=0.008$) ere used to generate high inductance and capacitance in limited small volume. Loops were designed on the same plane of resonator to reduce their volume, and there are three different size. The proposed MR-WPT system were fabricated with two acrylic substrate plane of Tx and Rx each, the Rx and Tx loops and resonators were fabricated of copper sheets. There are 12 combinations of 3 loops and 4 resonators, each combination were measured to calculate transfer efficiency and resonance frequency in transfer distance from 1cm to 5cm. The measured results, the highest transfer efficiency was about 70%, and average transfer efficiency was 40%, on the resonance frequency was about 6.78 MHz, which is standard band by A4WP. We proposed small-sized and planer resonator of MR-WPT and showed possibility of mobile applications for small devices.

Effects of Feedback Signals on DTV Repeaters (DTV 중계기의 궤환신호의 영향)

  • Kang, Sang-Gee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.10
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    • pp.1737-1743
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    • 2006
  • OCR(On channel repeater) provides the high frequency reuse efficiency for allocating frequency bands to repeaters because the frequency of input and output signals of OCRs is the same. However the oscillation probability of OCRs is high due to the same input and output frequency. In order to prevent a repeater from oscillating, we must keep the antenna isolation higher than the gain of the repeater with a some margin. In this paper we simulated the effects of the amplitude, phase and time delay of feedback signals (m the characteristics of non-regeneration OCR. Simulation results show that the highest probability of oscillation is occurred when the gain of a repeater is the same value of the isolation. From the simulation results, we know that the phase of feedback signals can be adjusted to reduce the possibility of oscillation if a non-regeneration repeater has a narrow operation bandwidth or a signal bandwidth is narrow. As the time delay increases, the probability of oscillation and the fluctuation of gain over a certain frequency band increase also. The effects of the amplitude and phase of feedback signals on S/N of 8-VSB signal for generation and non-generation repeater were tested. The measured results show that the set-top can receive 8-VSB signal when the received signal power is $17{\sim}18dB$ higher than the noise power. When the isolation is almost same as the gain of the repeater, then the set-top can not receive 8-VSB signals due to the oscillation of the repeater. And the phase of feedback signals affects S/N at the output of the repeater when the isolation is $11.75{\sim}13.75dB$ larger than the gain of the repeater. In this case the set-top can not receive 8-VSB signal of at $48^{\circ}\;and\;347^{\circ}$ of the phase of feedback signals. However the phase of feedback signals can not affect the S/N of 8-VSB signals of the generation repeater because of the demodulation and modulation process of the generation repenter. The set-top can not receive 8-VSB signals when the amplitude of feedback signals is $12.6{\sim}13.6dB$ larger than the wanted signal power at the input port of the repeater. It's because that the amplitude of feedback signals saturates the front end of the repeater.

Electroencephalographic Changes Induced by a Neurofeedback Training : A Preliminary Study in Primary Insomniac Patients (뉴로피드백 훈련에 의한 뇌파 변화 연구 : 일차성 불면증 환자에 대한 예비 연구)

  • Lee, Jin Han;Shin, Hong-Beom;Kim, Jong Won;Suh, Ho-Suk;Lee, Young Jin
    • Sleep Medicine and Psychophysiology
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    • v.26 no.1
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    • pp.44-48
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    • 2019
  • Objectives: Insomnia is one of the most prevalent sleep disorders. Recent studies suggest that cognitive and physical arousal play an important role in the generation of primary insomnia. Studies have also shown that information processing disorders due to cortical hyperactivity might interfere with normal sleep onset and sleep continuity. Therefore, focusing on central nervous system arousal and normalizing the information process have become current topics of interest. It has been well known that neurofeedback can reduce the brain hyperarousal by modulating patients' brain waves during a sequence of behavior therapy. The purpose of this study was to investigate effects of neurofeedback therapy on electroencephalography (EEG) characteristics in patients with primary insomnia. Methods: Thirteen subjects who met the criteria for an insomnia diagnosis and 14 control subjects who were matched on sex and age were included. Neurofeedback and sham treatments were performed in a random order for 30 minutes, respectively. EEG spectral power analyses were performed to quantify effects of the neurofeedback therapy on brain wave forms. Results: In patients with primary insomnia, relative spectral theta and sigma power during a therapeutic neurofeedback session were significantly lower than during a sham session ($13.9{\pm}2.6$ vs. $12.2{\pm}3.8$ and $3.6{\pm}0.9$ vs. $3.2{\pm}1.0$ in %, respectively; p < 0.05). There were no statistically significant changes in other EEG spectral bands. Conclusion: For the first time in Korea, EEG spectral power in the theta band was found to increase when a neurofeedback session was applied to patients with insomnia. This outcome might provide some insight into new interventions for improving sleep onset. However, the treatment response of insomniacs was not precisely evaluated due to limitations of the current pilot study, which requires follow-up studies with larger samples in the future.

Effect of Mushroom (Lentinus Tuber-Regium) Powder on the Bread Making Properties of Wheat Flour (버섯(Lentinus Tuber-Regium)분말 첨가가 제빵 특성에 미치는 영향)

  • Lee, Min-Jeong;Kyung, Kyu-Hang;Chang, Hak-Gil
    • Korean Journal of Food Science and Technology
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    • v.36 no.1
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    • pp.32-37
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    • 2004
  • Effects of mushroom powder on physicochemical characteristics of dough and bread-making properties were studied. In mixogram test, addition of 2-10% mushroom powder increased water absorption from 67,0 to 79%. Peak time, peak height, band width, and seven minute height of mushroom-wheat flour composite were similar to those of control. Sedimentation and P.K. values decreased with increasing amount of mushroom powder In amylogram test, no significant difference was observed in gelatinization temperature between control and mushroom powder-added dough. Peak viscosity increased with increasing amount of mushroom powder, Highest loaf volume was attained when 2 and 4% mushroom powders were added, whereas decreased above 6%. Bread weight and L value of crust increased with increasing amount of mushroom powder whereas 'a' value decreased. As the amount of mushroom powder increased, L value of crumb color decreased. No significant difference in springiness and adhesiveness was observed between control and mushroom-wheat composite flour bread whereas chewiness and gumminess, increased with increasing amount of mushroom powder, Hardness generally increased as the amount of mushroom powder increased. Mushroom powder caused bread staling at both storage temperatures ($4^{\circ}C\;and\;25^{\circ}C$). Although sensory value decreased with increasing mushroom powder, use of mushroom powder to replace up to 4% wheat flour is recommended in making bread.

Effect of Carrier Confinement and Optical Properties of Two-dimensional Electrons in Al0.3Ga0.7N/GaN and Al0.3Ga0.7N/GaN/Al0.15Ga0.85N/GaN Heterostructures (Al0.3Ga0.7N/GaN 및 Al0.3Ga0.7N/GaN/Al0.15Ga0.85N/GaN 이종접합 구조에서 운반자 구속 효과와 이차원 전자가스의 광학적 특성)

  • Kwack, H.S.;Lee, K.S.;Cho, H.E.;Lee, J.H.;Cho, Y.H.
    • Journal of the Korean Vacuum Society
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    • v.17 no.4
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    • pp.359-364
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    • 2008
  • We have investigated optical and structural properties of $Al_{0.3}Ga_{0.7}N$/GaN and $Al_{0.3}Ga_{0.7}N/GaN/Al_{0.15}Ga_{0.85}N/GaN$ heterostructures (HSs) grown by metal-organic chemical vapor deposition, by means of Hall measurement, high-resolution X-ray diffraction, and temperature- and excitation power-dependent photoluminescence (PL) spectroscopy. A strong GaN band edge emission and its longitudinal optical phonon replicas were observed for all the samples. At 10 K, a 2DEG-related PL peak located at ${\sim}\;3.445\;eV$ was observed for $Al_{0.3}Ga_{0.7}N$/GaN HS, while two 2DEG peaks at ${\sim}\;3.42$ and ${\sim}\;3.445\;eV$ were observed for $Al_{0.3}Ga_{0.7}N/GaN/Al_{0.15}Ga_{0.85}N/GaN$ HS due to the additional $Al_{0.15}Ga_{0.85}N$ layers. Moreover, the emission intensity of the 2DEG peak was higher in $Al_{0.3}Ga_{0.7}N/GaN/Al_{0.15}Ga_{0.85}N/GaN$ HS than in $Al_{0.3}Ga_{0.7}N$/GaN HS probably due to an effective confinement of the photo-excited holes by the additional $Al_{0.15}Ga_{0.85}N$ layers. The 2DEG-related emission intensity decreased with increasing temperature and disappeared at temperatures above 150 K. To investigate the origin of the new 2DEG peaks, the energy-band structure for multiple AlGaN/GaN HSs were simulated and compared with the experimental data. As a result, the observed high- and low-energy peaks of 2DEG can be attributed to the spatially-separated 2DEG emissions formed at different AlGaN/GaN heterointerfaces.

The Study on the Embedded Active Device for Ka-Band using the Component Embedding Process (부품 내장 공정을 이용한 5G용 내장형 능동소자에 관한 연구)

  • Jung, Jae-Woong;Park, Se-Hoon;Ryu, Jong-In
    • Journal of the Microelectronics and Packaging Society
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    • v.28 no.3
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    • pp.1-7
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    • 2021
  • In this paper, by embedding a bare-die chip-type drive amplifier into the PCB composed of ABF and FR-4, it implements an embedded active device that can be applied in 28 GHz band modules. The ABF has a dielectric constant of 3.2 and a dielectric loss of 0.016. The FR-4 where the drive amplifier is embedded has a dielectric constant of 3.5 and a dielectric loss of 0.02. The proposed embedded module is processed into two structures, and S-parameter properties are confirmed with measurements. The two process structures are an embedding structure of face-up and an embedding structure of face-down. The fabricated module is measured on a designed test board using Taconic's TLY-5A(dielectric constant : 2.17, dielectric loss : 0.0002). The PCB which embedded into the face-down expected better gain performance due to shorter interconnection-line from the RF pad of the Bear-die chip to the pattern of formed layer. But it is verified that the ground at the bottom of the bear-die chip is grounded Through via, resulting in an oscillation. On the other hand, the face-up structure has a stable gain characteristic of more than 10 dB from 25 GHz to 30 GHz, with a gain of 12.32 dB at the center frequency of 28 GHz. The output characteristics of module embedded into the face-up structure are measured using signal generator and spectrum analyzer. When the input power (Pin) of the signal generator was applied from -10 dBm to 20 dBm, the gain compression point (P1dB) of the embedded module was 20.38 dB. Ultimately, the bare-die chip used in this paper was verified through measurement that the oscillation is improved according to the grounding methods when embedding in a PCB. Thus, the module embedded into the face-up structure will be able to be properly used for communication modules in millimeter wave bands.

Analysis of Response Spectrum of Ground Motions from Recent Earthquakes (최근 발생지진 관측자료를 이용한 응답스펙트럼 분석)

  • Kim, Jun-Kyoung
    • Tunnel and Underground Space
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    • v.19 no.6
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    • pp.490-497
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    • 2009
  • The horizontal and vertical response spectra using the observed ground motion from the recent 5 macro earthquakes were analysed and then were compared to both the seismic design response spectra(Reg Guide 1.60), applied to the domestic nuclear power plants, and the Korean Standard Design Response Spectrum for general structures and buildings(1997). 74 horizontal and 89 vertical observed ground motions, without considering soil types, were used for normalization with respect to the peak acceleration value of each ground motion. The results showed that the horizontal MPOSD(Mean Plus One Sigma Standard Deviation) response spectra revealed much higher values for the whole frequency bands above 1 Hz than Reg. Guide(1.60). For the vertical response spectra, the results showed slightly higher than just between 7 and 8 Hz frequency band. The results were also compared to the Korean Standard Response Spectrum for the 3 different soil types and showed that the horizontal MPOSD response spectra revealed much higher values for the whole periods below 2 second(0.5 Hz) than those of SE soil type. The vertical response spectra showed similar to the values of the Korean Standard Response Spectrum of SD soil type. These spectral values dependent on frequency could be related to characteristics of the domestic crustal attenuation and the effect of each site amplification. However, through the qualitative improvements and quantitative enhancement of the observed ground motions, the conservation of horizontal seismic design response spectrum should be considered more significantly for the whole frequency bands above the 1 Hz.

Algorithm Implementation for Detection and Tracking of Ships Using FMCW Radar (FMCW Radar를 이용한 선박 탐지 및 추적 기법 구현)

  • Hong, Dan-Bee;Yang, Chan-Su
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.16 no.1
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    • pp.1-8
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    • 2013
  • This study focuses on a ship detection and tracking method using Frequency Modulated Continuous Wave (FMCW) radar used for horizontal surveillance. In general, FMCW radar can play an important role in maritime surveillance, because it has many advantages such as low warm-up time, low power consumption, and its all weather performance. In this paper, we introduce an effective method for data and signal processing of ship's detecting and tracking using the X-band radar. Ships information was extracted using an image-based processing method such as the land masking and morphological filtering with a threshold for a cycle data merged from raw data (spoke data). After that, ships was tracked using search-window that is ship's expected rectangle area in the next frame considering expected maximum speed (19 kts) and interval time (5 sec). By using this method, the tracking results for most of the moving object tracking was successful and those results were compared with AIS (Automatic Identification System) for ships position. Therefore, it can be said that the practical application of this detection and tracking method using FMCW radar improve the maritime safety as well as expand the surveillance coverage cost-effectively. Algorithm improvements are required for an enhancement of small ship detection and tracking technique in the future.

Design of Headset MIMO Antenna for On-Body Application (인체부착형 Headset MIMO 안테나 설계)

  • Kim, Sung-Jin;Kim, Dong-Ho;Kwon, Kyeol;Choi, Jae-Hoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.12
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    • pp.1107-1115
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    • 2011
  • In this paper, a headset multiple-input multiple-output(MIMO) antenna for on-body application is proposed and the antenna performance with body effect and the impact on human body are investigated. The proposed MIMO antenna is composed of two planar inverted-F antennas(PIFA) above ground plane and an isolator located between the two antennas enhance the isolation characteristic. Simulation was carried to analyze the effect of human body on antenna performance when a human body is located in the near field of the antenna. According to the measurement result, the diversity performance of the proposed antenna can be considered good since ECC(Envelope Correlation Coefficient), which commonly indicates the performance of a MIMO antenna, remains below 0.1 over the ISM band. The measured SAR values for antennas 1 and 2 are 0.575 W/kg and 0.571 W/kg, respectively when 250 mW input power in engaged. These values satisfy the FCC guideline which states that the 1-g average SAR should be lower than 1.6 W/kg.