• Title/Summary/Keyword: frequency rate

Search Result 6,560, Processing Time 0.038 seconds

Effects of Silver Spike Point Electrical Stimulation on Glomerular Filtration Rate in Volunteer (은침점전기자극의 인체적용이 신사구체여과율(Glomerular Filtration Rate)에 미치는 효과)

  • Chon, Ki-Young;Kim, Soon-Hee;Min, Kyung-Ok;Choi, Young-Duk;Lee, Joon-Hee;Kim, Jung-Hwan
    • Journal of Korean Physical Therapy Science
    • /
    • v.11 no.1
    • /
    • pp.28-35
    • /
    • 2004
  • The purpose of the present study was to investigate the effectiveness of silver spike point (SSP) low frequency electrical stimulation on glomerular filtration rate (GFR), specifically, such as diuretic action in 24 hour urine and in plasma analysis from normal volunteer. The current of 1 Hz continue type (CT) of SSP low frequency electrical stimulation significantly decreased in plasma creatine from normal volunteer. However, the urine creatinine clearance (Ccr) was significantly increased by SSP low frequency electrical stimulation in normal volunteer. These results suggest that the SSP low frequency electrical stimulation, especially current of 1 Hz continue type, significantly regulates urine creatinine clearance and glomerular filtration rate from normal volunteer. Therefore, the SSP low frequency electrical stimulation is a good regulator through a diuretic action of hypertension.

  • PDF

A Scheme on the Dynamic Load Shedding Using Rate of Frequency Decline (주파수 변화율을 이용한 동적부하차단 방안)

  • 이소영;장병태;이재욱;오화진;조범섭;김재현
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.52 no.6
    • /
    • pp.301-306
    • /
    • 2003
  • When a bulk power system experiences a serious disturbance or heavy load trip, the system frequency may drop and even collapse if the total generating power does not supply the system demand sufficiently. Since an isolated power system possesses a lower inertia and comes with limited reserves, the load shedding by under frequency relay becomes an important strategy to keep system natural frequency. This paper presents a scheme to determine the load shedding criteria by using the rate of change of frequency when the large disturbance happens.

Detachment Rate of Fruits of Lycium chinense Mill with Vibration Characteristic (진동특성에 의한 구기자 열매의 탈과율)

  • 서정덕;허윤근;이상우
    • Journal of Biosystems Engineering
    • /
    • v.25 no.2
    • /
    • pp.151-158
    • /
    • 2000
  • Detachment rate of mature fruits of the Lycium chinense Mill with various frequency, amplitude, and shaking time using an experimental vibratory system was analyzed. The experimental vibratory system was designed such that the frequency, amplitude, and shaking time could be controlled easily. The detachment rate increased as the frequency increased at constant amplitude and increased as the amplitude increased at constant frequency. The contents of the detached immature fruit, however, also increased as the frequency and amplitude increased, which was undesirable for the detachment efficiency considering the only mature 900 rpm and amplitude of 35 m for the shaking time of three seconds.

  • PDF

The Influence of Position Change on Autonomic Nervous System Function (자세변화가 자율신경계에 미치는 영향)

  • Kim, In-Bae;Kim, Eun-Kyung;Kang, Jong-Ho
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.9 no.1
    • /
    • pp.63-68
    • /
    • 2014
  • PURPOSE: The purpose of this study was to examine the position changes with tilt table on autonomic nervous system using heart rate variability analysis. METHODS: Fourty healthy adult males volunteered in this study. The low frequency, high frequency and low frequency/high frequency ratio and mean heart rate, standard deviation of all normal R-R intervals, root mean square of successive differences, heart rate variability index were measured at the tilt table angle of $0^{\circ}$, $45^{\circ}$ and $90^{\circ}$ with pulsoximeter. Data were analyzed one-way ANOVA and LSD post hoc test. RESULTS: The mean heart rate, low frequency and low frequency/high frequency ratio increased significantly at higher angle of tilt table(p<.05). The root mean square of successive differences, heart rate variability index decreased significantly at lower angle of tilt table(p<.05). The standard deviation of all normal R-R intervals, high frequency decreased at higher angle of tilt table did not show significant difference. CONCLUSION: The symphathetic activity increased significantly at higher angle of tilt table. The parasymphathetic activity decreased at higher angle of tilt table, but the difference were not significant. The autonomic adaptation, balance and heart rate variability decreased significantly at higher angle of tilt table. Based on these results, in the treatment of patients with a change in posture precedence should be carefully treated. Further studies are necessary to determine the most safety and effective methods.

A Study of Physical Responses for Work Loads (작업부하에 따른 생리적 반응들에 관한 연구)

  • 김재현;김홍기
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.25 no.1
    • /
    • pp.9-13
    • /
    • 2002
  • The objective of this study was to analyze and make comparison between the physical responses such as oxygen consumption rate, heart rate, and EMG-measurement for lifting tasks. Lifting activities with three different working frequencies(5, 8, 11 lifts/min) and two different weights(10, 20kg) for a lifting range(from floor to 76cm height) were studied. It was found that theme are positive correlations between the oxygen consumption rate and the EMG-measurements on the region of law back. Even though these physical responses were influenced by work weights and work frequency, it was found that the work frequency plays more important role in making muscle fatigue than the work weight. From these finding it is suggested that the work frequency should be considered as a more influencing factor than the work weight as long as the weight belongs to the permissible range based on the viewpoint of the biomechanical criterion for designing a job of manual materials handling tasks.

Heart Rate Variability Analysis for Significance Between Ag/AgCl Electrode and Electric Textile Sensor in Wearable Condition

  • Shin, Hang-Sik;Lee, Chung-Keun;Yun, Yong-Hyeon;Lee, Myoung-Ho
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.453-456
    • /
    • 2005
  • Significance verification of electric fabric compared with existing electrode is very useful for the wearable and ubiquitous healthcare. In this paper, we verified the significance between Ag/AgCl electrode and electric fabric in dry-normal condition through heart rate variability analysis. We can find 98 % or more similarity about low frequency and high frequency which is important parameter for the heart rate variability analysis between two different electrodes in experiment. From this result, we confirmed that the power spectral density of low frequency, high frequency component from the electric fabric has high similarity compared with the result of heart rate variability from Ag/AgCl electrode in dry-normal condition.

  • PDF

Stuttering Reduction Rate during Sentence Reading: Choral Speech and Altered Auditory Feedback (문장읽기에서의 말더듬 감소율: 합독과 변조청각피드백)

  • Park, Jin;Park, Heeyoung
    • Phonetics and Speech Sciences
    • /
    • v.4 no.4
    • /
    • pp.109-115
    • /
    • 2012
  • This paper mainly aims to investigate how differently choral speech and altered auditory feedback (i.e., delayed auditory feedback, frequency-altered feedback) enhance speech fluency during sentence reading. To do this, a stuttering reduction rate was used and measured how much stuttering in frequency was reduced during each of the fluency enhancing conditions (i.e, typical choral reading, DAF, FAF) relative to typical solo reading. The results showed that stuttering frequency was reduced in the three fluency enhancing conditions and the highest mean value in stuttering reduction rate was observed during typical choral reading. Some discussion was provided in relation to the stuttering reduction rate observed during typical choral reading and its further speculation.

Arbitrary Sampling Method for Nonlinearity Identification of Frequency Multipliers

  • Park, Young-Cheol;Yoon, Hoi-Jin
    • Journal of electromagnetic engineering and science
    • /
    • v.8 no.1
    • /
    • pp.17-22
    • /
    • 2008
  • It is presented that sampling rates for behavioral modeling of quasi-memory less nonlinear devices can be far less than the Nyquist rate of the input signal. Although it has been believed that the sampling rate of nonlinear device modeling should be at least the Nyquist rate of the output signal, this paper suggests that far less than the Nyquist rate of the input signal can be applied to the modeling of quasi-memoryless nonlinear devices, such as frequency multipliers. To verify, a QPSK signal at 820 MHz were applied to a frequency tripler, whereby the device can be utilized as an up-converting mixer into 2.46 GHz with the aid of digital predistortion. AM-AM, AM-PM and PM-PM can be successfully measured regardless of sampling rates.

Call admission scheme for low speed multimedia services in CDMA mobile communication systems (CDMA 이동통신시스템에서의 저속 멀티미디어 서비스를 위한 호 수락 방식)

  • 최경수;권수근;전형구;유영갑
    • Journal of the Korean Institute of Telematics and Electronics S
    • /
    • v.35S no.7
    • /
    • pp.14-21
    • /
    • 1998
  • In providing with low speed multimedia services, a call blocking rate is greatly varied according to the transmission rate, and thereofr, the call blocking rate is remarkably increased for a service having a high transmission rate compared to a service having a low transmission rate. This paper presents three methods of solving this problem; Packing Scheme in which available channels distributed to each frequency channel are concentrated on one frequency channel and a call having a high transmission rate is assigned to the frequency channel; Queuing Scheme in which queuing is assigned to calls under service is temporarily reduced and a call having a high transmission rate is allowed. The result of performance analysis for 13 Kbps and 128 Kbps service through computer simulation showed that the call blocking rate for 128 Kbpx service was reduced by tens of percent accoring to loads.

  • PDF

Performance Evaluation of Fill Rate Quasi-orthogonal STF-OFDM with DAC-ZF Decoder for Four Transmit Antennas MIMO System (4개의 송신 안테나 MIMO 시스템을 위한 DAC-ZF 수신 기법과 결합된 Full Rate 준직교 QOSTF-OFDM 관한 연구)

  • Jin, Ji-Yu;Ryu, Kwan-Woong;Park, Yong-Wan
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.31 no.11A
    • /
    • pp.1092-1100
    • /
    • 2006
  • In this paper, we propose a full rate quasi-orthogonal space-time-frequency block coded orthogonal frequency division multiplexing(QOSTF-OFDM) that can achieve full symbol rate with four transmit antennas. Sincr: the proposed QOSTF-OFDM can not achieve full diversity, we use diversity advantage collection with zero forcing (DAC-ZF) decoder to compensate the diversity loss at receive side. At the same frequency efficiency, compared with linear orthogonal space-time codes which can not achieve full rate with four transmit antennas over complex constellations, low level modulation can be employed by proposed scheme due to its full rate, i.e., modulation advantage can be achieved. Due to modulation advantage and collected diversify advantage, the proposed scheme exhibits better BER performance than other orthogonal schemes.