• Title/Summary/Keyword: Rms

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Changes in Surface EMG Parameters during Dynamic Wheelchair Propulsion (휠췌어 추진시 근전도 신호의 특성 변화)

  • Choi, Hwa - Soon
    • The Journal of Korean Physical Therapy
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    • v.13 no.3
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    • pp.777-789
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    • 2001
  • The purpose of this study was to investigate the possibility of using surface electromyographic signals as a measure of muscle fatigue during the wheelchair propulsion. Subjects performed wheelchair exercise tests on a motor-driven treadmill with a constant-velocity of 1.25 m/sec. During each test, the raw EMC signals were acquired from the surface electrodes attached on the belly of five muscle groups: biceps brachii, pectoralis major. deltoid, triceps brachii, and trapezius. The median power frequency(MPF), and the root mean square(RMS) amplitude were calculated for each cyclic contraction in order to quantify muscle fatigue. During the wheelchair propulsion, the MPF decreased and the RMS increased in the trapezius and deltoid. However, the decreasing MPF and the increasing RMS also fluctuated severly during dynamic muscle contractions. Therefore, the MPF and RMS values should be estimated with well-designed methods and used with caution to quantify muscle fatigue during wheelchair propulsion.

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The Effect of Working Hour on Muscle Fatigue in Visual Display Workplace (VDT 작업환경에서 작업시간이 근피로에 미치는 영향)

  • 한정수
    • Journal of the Korean Society of Safety
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    • v.15 no.1
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    • pp.153-160
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    • 2000
  • Occupational cumulative traumas (CTDs) are becoming one of leading ailments in industrialized worl $d^{(1.2)}$. The degree of muscle fatigue is important parameter to understand cause of occupational cumulative trauma disorders. To quantify degree of muscle fatigue, muscle EMG activity was measured during isometric and dynamic contractions(repetitive concentric/eccentric muscle contraction) and its analyzed data, such as RMS, median frequency, and median power were compared when the muscle was fresh and exhausted. When muscle become fatigue, it was observed that median frequency decreased and median power and RMS increased However, based on overall prolonged observation, median frequency increased and median power and RMS decreased. Therefore it was concluded that shifting patterns of RMS, median frequency, and median power values can be used as parameter to evaluate degree of muscle fatigue even in dynamic muscle contraction.

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Peformance Analysis of Scheduler Selection based Real-time Linux Systems (스케줄러 선택기반의 실시간 리눅스의 성능분석)

  • Kang, Min-Goo
    • Journal of Internet Computing and Services
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    • v.8 no.1
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    • pp.71-78
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    • 2007
  • In this paper, an effective task scheduling scheme was proposed for the flexible real time LINUX systems with the selection between EDF(earliest deadline first) and RMS(rate monotonic scheduling). It was known that many task scheduling schemes were analyzed according to the characteristics of scheduling schemes and the guarantee of an earliest deadline scheduler for process utilities.

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Relationship between EMG Signals and Work during Isokinetic Exercise of Knee Extensor (슬관절 신전근의 등속성 운동 시 발생되는 일과 근전도 신호와의 관계)

  • Won, Jong-Im
    • Journal of Korean Physical Therapy Science
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    • v.10 no.1
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    • pp.83-89
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    • 2003
  • An electromyogram (EMG) using surface electrodes is one of the indirect tests most frequently used to ascertain muscle fatigue. An EMG can be used in two ways. The first technique determines the root mean square (RMS), which reflects the amplitude of the EMG signal. The second technique determines the median and mean power frequencies through EMG power spectrum analysis. The purpose of this article is for determine the correlation between work and percent root mean square(%RMS) and between work and MDF of EMG based on muscle contractions. It is used the %RMS, which reflects the amplitude of the EMG signal For MDF, it is used the frequency power spectrum analysis method, which involves the fast Fourier transformation (FFT) of the original Signals.

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Rhabdomyosarcoma of the tongue base, its recurrence, and multiple lymph node metastases with imaging evidence

  • Kim, Young-Ho;Choi, Bo-Ram;Huh, Kyung-Hoe;Yi, Won-Jin;Lee, Sam-Sun
    • Imaging Science in Dentistry
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    • v.38 no.4
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    • pp.225-228
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    • 2008
  • Rhabdomyosarcoma (RMS) is an aggressive and fast-growing malignant tumor. RMS predominantly arises in the head and neck of infancy and children. Metastasis is usually via the blood vessel. We report a case of a recurred RMS of the tongue base with the metastasis to multiple lymph nodes in a 37-year-old female. On the follow-up examination using advanced imaging modalities after surgical treatment of RMS, the lymph nodes should be carefully evaluated like in other malignancies, such as a carcinoma, showing frequent lymph node metastasis. (Korean J Oral Maxillofac Radiol 2008; 38 : 225-8)

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Transonic Magnetohydrodynamic Turbulence

  • LEE HYESOOK;RYU DONGSU;KIM JONGSOO;JONES T. W.
    • Journal of The Korean Astronomical Society
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    • v.34 no.4
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    • pp.321-323
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    • 2001
  • Compressible, magnetohydrodynamic (MHD) turbulence in two dimension is studied through high-resolution, numerical simulations with the isothermal equation of state. First, hydrodynamic turbulence with Mach number $(M)_{rms}\;\~$1 is generated by enforcing a random force. Next, initial, uniform magnetic field of various strengths with Alfvenic Mach number Ma $\gg$ 1 is added. Then, the simulations are followed until MHD turbulence is fully developed. Such turbulence is expected to exist in a variety of astrophysical environments including clusters of galaxies. Although no dissipation is included explicitly in our simulations, truncation errors produce dissipation which induces numerical resistivity. It mimics a hyper-resistivity in our second-order accurate code. After saturation, the resulting flows are categorized as SF (strong field), WF (weak field), and VWF (very weak field) classes respectively, depending on the average magnetic field strength described with Alfvenic Mach number, $(Ma)_{rms}{\ge}1$, $(Ma)_{rms}{\~}1$, and $(Ma)_{rms}{\gg}1$. The characteristics of each class are discussed.

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A Study on Synchronization for ATM Terminal (ATM 단말기의 동기에 관한 연구)

  • Choe, Seung-Guk
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.7
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    • pp.1877-1883
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    • 1999
  • Synchronization of the clock at the ATM receiving terminal is studied. The technique analyzed here has been adapted by ITU-T as the standard for ATM timing recovery. This paper presents analysis of SRTS method itself and jitter in SRTS. The power pectrum and rms amplitude of SRTS jitter are calculated. The calculated average rms value for T1 1.544MHz source signal is 32.63ns and 0.15ns for E4 139.264MHz signal.

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Study of Sequale of Low Back Pain in Traffic Accident Patients (교통사고 환자의 요통후유증에 대한 고찰)

  • Cho, Won-young;Lee, Kyoung-yoon;Park, Kwae-hwan
    • Journal of Acupuncture Research
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    • v.20 no.6
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    • pp.36-44
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    • 2003
  • Objective: We have various ways in evaluating the level of low back pain as sequelae, general approaches such as neurologic examination, MRI, Radiologic examination and evaluating the effect of psychological stress on the low back pain. Besides We can find another approach to evaluating the sequale of low back pain in TA patients. So, I intend to analyze how much relationship the patients that got low back pain by TA have with Roland Morris Disability Scale(RMS) in 2 months after discharge. Methods: In this article, I will compare two results of TA inpatients and non-TA inpatients, which obtained with the RMS. This study was carried out about 22 TA patients and 18 non-TA patients, who had low back pain and were hospitalized between March 2002 and July 2002. Results & conclusions : 1. RMS point is related with the post-discharge term to a point of time of answering the questionnaire in both TA patients and non-TA patients. 2. In distribution of RMS point, Gr II take most possesion as 41% in TA patients while Gr I take most possesion as 56% in non-TA patients. 3. In distribution of RMS point, patients that correspond to more than Gr III take 27% in TA patients, 16% in non-TA patients. 4. TA patients show higher level of distribution than non-TA patients in RMS point in verifying them by mean value and T-test. 5. Degree of pain score change(${\Delta}$P.S), using mean value and T-test, showed lower level of distribution in TA patients than non-TA patients. 6. We can see that TA patients have more restriction in their life for low back pain.

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A Study on the Radio Wave Propagation Model in IMT-2000 (IMT-2000 주파수대역에서의 전파-전파 모델에 관한 연구)

  • Ra, Yoo-Chan;Lee, Seung-Woo;Shin, Hong-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.4A
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    • pp.224-231
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    • 2003
  • In this in this thesis, we have proposed the Kor-231 which compared with Hata by dividing 4 classes and 8 details, which based on that the area subdivision which is defined by the City planning Regulation of Korea classified on its rate of building-to-land, floor area and distance between buliding and botanical coefficient. The experiments are carried out at the point of the RMS delay spread and the recerived power in the two kinds of geographical areas, LOS(Line of Sight) and N-LOS(Non Line of Sight). When the measured result is compared with Kor-231 model, we can catch the result that received power are 25.5dB and 14.5dB, the RMS delay spread are 101ns and 35ns and N-LOS received power are 4.1dB and 1.6dB. So we have certified that it is well due to the result analyzed into the difference of the RMS delay spread from 74ns to 200ns.

Current and voltage loading tests off resistive SFCL

  • 최효상;현옥배;김혜림;황시돌;박권배
    • Progress in Superconductivity
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    • v.3 no.2
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    • pp.241-246
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    • 2002
  • We have performed the current and voltage loading tests of resistive superconducting fault current limiters (SFCLS) based on $YBa_2$$Cu_3$$O_{7}$(YBCO) films with the diameter of 2 inch. The SFCL consists of meander-type YBCO stripes covered with 200 nm Au layer grown in situ for current shunt and heat dispersion at hot spots. The minimum quench current of an SFCL unit was about 25 Apeak. Seven SFCL units were connected in parallel fur the current load ing tests at power source of 100 $V_{rms}$ $/2,000A_{rms}$. This SFCL units had maximum limiting current of 170 Apeak during the fault instant and then successfully controlled the fault current below 100 Apeak within 1~2 msec after short circuit. Increased short current also reduced the quench completion time with little change of current limiting characterization. We connected six SFCL units in series fur the voltage loading tests at power source of $1,200 V_{rms}$/170 $A_{rms}$ at this time. The shunt resistors were inserted into each SFCL unit to eliminate power imbalance originated from serial connection of SFCL units. Each SFCL unit was quenched simultaneously during the fault condition. The current increased up to 40 $A_{peak}$ and decreased to 14 $A_{peak}$ after 3 cycles. Quench was completed within 1 msec after the fault. We confirmed operating characteristics of 140 kVA($120 A_{rms}$ $\times$ 1,200 $V_{rms}$) SFCL and presented the manufacturing possibility of 3.3 kV SFCL using 4 inch YBCO films.BCO films.lms.

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