• Title/Summary/Keyword: Fast SCR

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Low Computational FFT-based Fine Acquisition Technique for BOC Signals

  • Kim, Jeong-Hoon;Kim, Binhee;Kong, Seung-Hyun
    • Journal of Positioning, Navigation, and Timing
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    • v.11 no.1
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    • pp.11-21
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    • 2022
  • Fast Fourier transform (FFT)-based parallel acquisition techniques with reduced computational complexity have been widely used for the acquisition of binary phase shift keying (BPSK) global positioning system (GPS) signals. In this paper, we propose a low computational FFT-based fine acquisition technique, for binary offset carrier (BOC) modulated BPSK signals, that depending on the subcarrier-to-code chip rate ratio (SCR) selectively utilizes the computationally efficient frequency-domain realization of the BPSK-like technique and two-dimensional compressed correlator (BOC-TDCC) technique in the first stage in order to achieve a fast coarse acquisition and accomplishes a fine acquisition in the second stage. It is analyzed and demonstrated that the proposed technique requires much smaller mean fine acquisition computation (MFAC) than the conventional FFT-based BOC acquisition techniques. The proposed technique is one of the first techniques that achieves a fast FFT-based fine acquisition of BOC signals with a slight loss of detection probability. Therefore, the proposed technique is beneficial for the receivers to make a quick position fix when there are plenty of strong (i.e., line-of-sight) GNSS satellites to be searched.

Emotional Preference Modulates Autonomic and Cortical Responses to Tactile Stimulation (촉각자극에 의한 자율신경계 및 뇌파 반응과 감성)

  • Estate Sokhadze;Lee, Kyung-Hwa;Imgap Yi;Park, Sehun;Sohn, Jin-Hun
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 1998.11a
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    • pp.225-229
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    • 1998
  • The purpose of the current study was comparative analysis of autonomic and electrocortical responses to passive and active touch of the tektites with different subjective emotional preference. Perspective goal of the project is development of a template for classification of tactile stimuli according to subjective comfort and associated physiological manifestations. The study was carried out on 36 female college students. Physiological signals were acquired by Grass and B10PAC 100 systems with AcqKnowledge III software. Frontal, parietal and occipital EEG (relative power spectrum /percents/ of EEG bands - delta, theta, slow and fast alpha, low and fast beta), and autonomic variables, namely heart rate (HR), respiratory sinus arrhythmia (RSA), pulse transit time (PTT), respiration rate (RSP) and skin conductance parameters (SCL, amplitude, rise time and number of SCRs) were analyzed for rest baseline and stimulation conditions. Analysis of the overall pattern of reaction indicated that autonomic response to tactile stimulation was manifested in a form of moderate HR acceleration, RSP increase, RSA decrease (lowered vagal tone), decreased n and increased electrodermal activity (increased SCL, several SCRs) that reflects general sympathetic activation. Parietal EEG effects (on contra-lateral side to stimulated hand) were featured by short-term alpha-blocking, slightly reduced theta and significantly increased delta and enhanced fast beta activity with few variations across stimuli. The main finding of the study was that most and least preferred textures exhibited significant differences in autonomic (HR, RSP, PTT, SCR, and at less extent in RSA and SCL) and electrocortical responses (delta, slow and fast alpha, fast beta relative power). These differences were recorded both in passive and active stimulation modes, thus demonstrating reproducibility of distinction between most and least emotionally preferred tactile stimuli, suggesting influence of psychological factors, such as emotional property of stimulus, on physiological outcome. Nevertheless, development of sufficiently sensitive .and reliable template for classification of emotional responses to tactile stimulation based on physiological response pattern may require more extensive empirical database.

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A Study on Operation Scheme of STS with Emergency Generator for Peak Shedding (첨두부하 저감을 위한 비상발전기 연계형 STS 운영 방안에 관한 연구)

  • Kim, Chang-Hwan;Rhee, Sang-Bong;Kim, Kyu-Ho
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.155-156
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    • 2015
  • Recently, electricity consumption has rapidly increased along with economic growth. The operating strategy using emergency generator is aimed, to resolve a demand response management. For strategy of peak shedding using emergency generator, it is essential to introduce the fast transfer switching device. One of the most effective solutions is to use a static transfer switch (STS) based on thyristor. However, the characteristic of natural commutated SCR thyristor should anticipate short duration voltage sag. STS system thus requires more than a quarter cycle to successfully complete transfer process. This paper proposes the operation scheme of the STS system using the forced-commutation technique to mitigate instantaneous voltage sag during peak transfer process. Proposed STS system improved turn-off characteristic thus accomplishes the peak load shedding satisfied power quality. Performance of the proposed STS system is evaluated using electromagnetic transient program (EMTP) to confirm the effectiveness.

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Passive and Active Touch of Fabrics: Psychophysiological Responses Modulation by the Emotional Preference of Touched Textures

  • Estate Sokhadze;Imgap Yi;Lee, Kyunghwa;Shon, Jin-Hun
    • Science of Emotion and Sensibility
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    • v.1 no.2
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    • pp.13-22
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    • 1998
  • The sense of touch has both objective and subjective characteristics. During hand evaluation of the fabrics. psycho physiological processes such as emotion and stimulation. On other site, the mode of touch (passive vs. active) is also capable to modulate somatosensory responses. I.e., suppress somatocensory perception during active electrocortical responses to passive and active touch of the textiles with different subjective emotional preference. The study was carried out on 36 female college students. Physiological signals were acquired by Grass and BIOPAC 100 systems with AcqKnowledge variables, namely heart rate (HR), respiratory sinus arrhythmia (RSA), pulse transit time (PTT), respiration rate (RSP) and skin conductance parameters (SCL, amplitude, risetime and number of SCRs) were analyzed for baseline and stimulation conditions. Analysis was manifested in a form of moderate HR acceleration. RSP increase, RSA decrease (lowered vagal tone), decreased PTT and increased electrodermal activity (increased SCL, several SCRs) that reflects general sympathetic activation. Parietal EEG effects (on contra-lateral side to stimulated hand)were featured by short-term alpha-blocking, slightly reduced theta, significantly increased delta and enhanced fast beta activity with few variations across stimuli. The main finding of the study was that most and least preferred textures exhibited significant differences in autonomic (HR, RSP, PTT, SCR, and at less extent in RSA and SCL) and electrocortical responses (delta, slow and fast alpha, fast beta relative power). These differences were recorded both in passive and active stimulation modes, thus demonstrating reproducibility of distinction between most and least emotionally preferred tactile stimuli, suggesting influence of psychological factors, such as emotional property of stimulus, on physiological outcome.

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The Optimization of Output Characteristics with High Repetition Rate Pulsed $CO_2$ Laser Using SMPS (SMPS 방식의 고반복 펄스형 $CO_2$레이저의 출력특성 최적화)

  • Lee, D.H.;Chung, H.J.;Kim, D.W.;Kim, W.Y.;Kim, H.J.;Cho, J.S.
    • Proceedings of the KIEE Conference
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    • 1999.07e
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    • pp.2192-2194
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    • 1999
  • In this study, We have accomplished a new approach to develope a cheap and compact pulsed $CO_2$ laser system. We used a fast SCR as switching device instead of a thyatron in the pulsed power supply. Using the Pulse transformer, energy in the condenser is tranferred to the secondary, electrodes of discharge tube, from the primary. An axial and water cooled type was adopted as the laser cavity. The laser performance characteristics as various parameters, such as gas pressure and pulse repetition rate, have been investigated. As a result, the maxium laser output was 12.3[W] at a pulse repetition rate of 120[pps] and a filling pressure of 12[Torr].

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The influence habituation on psychophysiological differentation of automobile horns with different psychoacoustic characteristics (자극 습관화가 자동차 경적음의 심리음향 특성에 따른 심리생리적 予분에 미치는 영향)

  • Min Yoon-Ki;Sokhadze Estate M.;Yi ImGap;Jho Moon Jae;Sohn Jin-Hun
    • Proceedings of the Acoustical Society of Korea Conference
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    • spring
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    • pp.263-268
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    • 1999
  • Psychoacoustic characteristics of automobile hems influence subject's subjective evaluation and psychophysiological reactions on the sounds of car horns. However, differentiation of physiological responses to commercially availablenfluence subject's subjective evaluation and psychophysiological reactions on the s horns is a complicated task due to the small contrast in technical features of horns and the influence of habituation. Using 10 college students, comparative analysis of physiological reactivity was carried out in order to identify the effect of habituation on decrement of psychophysiological responsivity, assess the ability to differentiate subjectively most and least preferred/appropriate horns according to physiological manifestations. EEG and autonomic responses to 7 automobile horns were analyzed during 3 blocks of trials (each block was varied in order for presenting stimuli and acoustic parameters of horns). It was shown that electrodermal and cardiovascular responses had different reactivity patterns to repeated stimulation. Skin conductance variables (SCL, SCR) were habituated as a function of trial. Cardiac reactivity (HR, RSA) showed no signs of habituation. In contrast, sensitization was shown in the vascular component of response (pulse volume). The temporal EEG exhibited marked habituation of fast beta band power, while alpha-blocking effect did not habituate during the course of experiment. Differentiation of physiological responses of most and least preferred/appropriate horns was possible in this study. That is, some cardiovascular reactivity variables (HR, RSA, pulse volume, etc.) were differentiated between the least and the most preferred/appropriate horns during the experiment. However, EEG and electrodermal parameters showed significant differences only during first block of trials and were later affected by habituation.

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Semantische Unbestimmtheit der Skalaradjektiven (척도형용사의 의미적 불확정성에 대한 연구)

  • Chung Dong-Gyu
    • Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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    • v.10
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    • pp.277-296
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    • 2004
  • Ein sprachlicher Ausdruck ist in verschiedenen Situationen in einer Vielzahl unterschiedlicher Lesarten oder $Pr\"{a}zisierungen$ verwendbar, und zwar mil dom Grad an $Pr\"{a}zision$, der den jeweiligen kormmunikativen Erfordernissen angemessen ist. Sokommt Vagheit/$Ambiguit\"{a}t$ in sprachlichen Ausdrucken fast $durchg\"{a}ngig$ vol. In der vorliegenden Albeit wird die $M\"{o}glichkeit$ der semantischen $\"{U}bersetzung$ der Skalaradjektiven($gro{\ss}$, klein, $hei{\ss}$, kalt, schwer, leicht, schnell, langsam usw.) untersucht, die eigentlich die Vagheit als eine der konstitutiven Eigenschaften haben. Den Schwerpunkt $daf\"{u}r$ bildet die semantische Analyse $\"{u}ber$ die Graduierbarkeit und Vergleichbarkeit der Positivformen der Adjektiven, die vol allem M.J.Cresswell 1976 in seiner Albeit formuliert hat. V(pos) is the function $\eta$ in $D_{{\lll}{0,1}>,<{0,1}{\gg}.{\ll}{0,1,1},>,<{0.1}{\ggg}$ such that where ${\xi}{\in}D_{{\ll}{0,1,1},><{0,1}{\gg}$,$\eta({\xi})$ is the following function: For any ${\omega}{\in}D_{<0,1>$and a ${\in}D_1$ and w$\in$W, w${\in}{\eta}({\xi})({\omega})$(a) iff w ${\in}{\omega}$(a) and there is exactly one b such that ${\xi}({\omega})$(a,b); and for that b, b=$\gg$(for some > and u ${\in}{ \scr}{Z}(>))$ and u is toward the top of the scale determined by > when restricted to those v such that for some c, w${\in} {\xi}({\omega})$$(c,{\;} and w${\in}{\omega}(c)$. (Cresswell, 1976: 272) Obwohl sein Verfahren anhnd von dem semantischen Symbol eine methodische und theoretische $Ad\"{a}quatheit$ erf\"{u}llt$, bleibt der Vergleichwert noch unterspezifiziert. Fur die Behandlung dieser semantischen Unterspezifikation ist eine neue Semantik erforderlich, die den Wahrheitwert fur die $Zugeh\"{o}rigkeitsgrade$ der Skalaradjektive $einschlie{\ss}t$.

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