• Title/Summary/Keyword: sonic vibration

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Development of sonic wave leg press system (음파를 이용한 진동 레그프래스 운동기구개발)

  • Min, Jin-Young
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1501-1504
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    • 2008
  • By applying sonic wave vibration technology in weight exercise equipment, we introduced an completely new concept of device into the fitness and medical industry creating a new trend. Sonic wave leg press exercise system which got over the limit of technology will be easily accessible not only by professional athletes but also by ordinary users and even minority groups such as disabled, elderly, children.

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The vibration exercise device development which uses the sonic wave (음파를 이용한 진동운동기구개발)

  • Min, Jin-Yeong
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.135-136
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    • 2008
  • By applying sonic wave technology in Vibration Exercise Equipment, we introduced an completely new concept of device into the fitness and medical industry creating a new trend. Sonic Vibration Exercise Equipment which got over the limit of technology will be easily accessible not only by professional athletes but also by ordinary users and even minority groups such as disabled, elderly, children.

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공기역학적 소음에 대하여

  • 노오현
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1996.10a
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    • pp.15-23
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    • 1996
  • 강연의 내용은 주로 유동에 의하여 발생되는 소음으로 제한하지만 초음속 항공기에 형성된 충격파 소음인 Sonic Boom도 함께 간단히 소개하고자 한다.

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Determination of Elastic Modulus by Time Average ESPI and Euler-Bernoulli Equation (Time Average ESPI와 Euler-Bernoulli 방정식에 의한 탄성계수 측정)

  • Kim, Koung-Suk;Lee, Hang-Seo;Kang, Young-June;Kang, Ki-Soo
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.7 s.196
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    • pp.69-74
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    • 2007
  • The paper proposes a new sonic resonance test for a elastic modulus measurement which is based on time-average electronic speckle pattern interferometry(TA-ESPI) and Euler-Bernoulli equation. Previous measurement technique of elastic constant has the limitation of application for thin film or polymer material because contact to specimen affects the result. TA-ESPI has been developed as a non-contact optical measurement technique which can visualize resonance vibration mode shapes with whole-field. The maximum vibration amplitude at each vibration mode shape is a clue to find the resonance frequencies. The dynamic elastic constant of test material can be easily estimated from Euler-Bernoulli equation using the measured resonance frequencies. The proposed technique is able to give high accurate elastic modulus of materials through a simple experiment set up and analysis.

Calibration of Discharge Coefficient of Sonic Nozzle Using CVFM (정적형 유량계를 이용한 소닉노즐 유출계수 교정 방법에 관한 연구)

  • Shin, J.H.;Kang, S.B.;Park, K.A.;Lim, J.Y.;Cheung, W.S.
    • Journal of the Korean Vacuum Society
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    • v.19 no.4
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    • pp.243-248
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    • 2010
  • Sonic nozzles have been a standard device for measurement of steady state gas flow, as recommended in ISO 9300. This paper introduces two sonic nozzles of diameter ${\Phi}$ 0.03 mm and ${\Phi}$ 0.2 mm precisely machined according to ISO 9300. The constant volume flow meter(CVFM), readily set up in the Vacuum center of KRISS. was used to calibrate the discharge coefficients of both nozzles. The calibration results were shown to determine them within the 3% expanded measurement uncertainty. Calibrated sonic nozzles were found to be applicable for precision measurement of steady state gas flow in the vacuum process in the ranges of 0.6~1,800 cc/min. Those flow conditions are equivalent to the fine gas flow with Reynolds numbers of 26~12,100. Those encouraging results confirm that calibrated sonic nozzles enable precision measurement of extremely low gas flow encountered very often in th vacuum processes. Both calibrated sonic nozzles are proven to provide the precision measurement of the volume flow rate of the dry vacuum pump within one percent difference in reference to CVFM. Calibrated sonic nozzles are applied to a new 'in-situ and in-field' equipment designed to measure the volume flow rate of vacuum pumps in the semiconductor and flat display processes. Furthermore, they can provide other applications to flow control devices in vacuum, such as MFC, etc.

The Effects of Circuit Training and Circuit Training with Whole Body Vibration on Pulmonary Function in Adolescent

  • Jun, Hyun ju;Jeong, Chan Joo;Yang, Hoe Song;Jeong, Ye rim;Jegal, Hyuk;Yoo, Young Dae
    • Journal of International Academy of Physical Therapy Research
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    • v.6 no.2
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    • pp.902-907
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    • 2015
  • The purpose of this study was to parallel circuit training and circuit training with sonic systemic mechanism was to compare the differences in pulmonary function and chest expansion in adult men. This study was performed on 20 subjects. 20 subjects were divided into two groups; Circuit training group(n=10), Circuit training with sonic systemic mechanism(n=10). Both of the group performed the exercise 3 times a week for 5 weeks. The data was analyzed by the Repeated t-test for comparing before, during and after changes of factors in each group and the Independent t-test for comparing the between groups. The result are as follows. Circuit training group was statistically significant difference FVC, FEV1/FVC(p<.05), Circuit training with sonic systemic mechanism group was statistically significant difference PEF, VC in pulmonary function(p<.05). Circuit training group was statistically significant difference FEV1/FVC of between the two group in pulmonary function(p<.05). Circuit training group and circuit training with sonic systemic mechanism group was statistically significant difference in chest expansion(p<0.05) and there was no statistically significant difference of between the two group in chest expansion(p>.05).

Structure Excitation by Using Beating (맥놀이 현상을 이용한 구조물 진동 가진)

  • Choi, Young-Chul;Park, Jin-Ho;Yoon, Doo-Byoung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.19 no.10
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    • pp.1028-1033
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    • 2009
  • To detect faults and monitor thinning on a pipe, many people use ultra sonic sensors that are operated in high frequency range. Because there are many modes in high frequency range, it is difficult to find faults and monitor pipe thinning on a structure. If we deal with signals in a low frequency range which include only A0 wave and S0 wave, the information of monitoring and diagnosis can be easily obtained. In this paper, the technique for exciting low frequency range using ultra sonic sensors is proposed. The main idea of the proposed method comes from the beat phenomenon. The beat frequency is equal to the absolute value of the difference in frequency of the two waves. If the beat frequency is tuned by two ultra waves, we can excite A0 mode and S0 mode of structures. To verify the proposed method, we have performed a steel plate and pipe experiments. Experimental results show that two ultra sonic sensors can well excite low frequency range.

Development of an Expert System for Optimizing Die and Mold Polishing-I (금형면 자동 다듬질 전문가 시스템 개발에 관한 연구-I -DB 구축을 위한 회전 및 진동 연마 가공의 실험적 연구-)

  • 민헌식;이성환;안유민;조남규;한창수
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.11 no.1
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    • pp.38-44
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    • 2002
  • In manufacturing die and mold, polishing: is important as it takes as much as 50% of the production cost. In this research, an attachable type polishing device to a WC machining center was developed. experiments were done with a special1y designed rotation type polishing device. Also an ultra-sonic (vibration type) waving device was introduced to acquire finer surface finishes. From the constructed data base based on the experimental results, it is shown that optimal polishing conditions are generated by the combined use of the rotation type tool and the vibration type tool.

Comparison of the Effects of Unstable Support Exercise Using Whole Body Sonic Vibrator and TOGU for Patients with Ankle Instability (발목 불안정환자에 대한 전신음파진동기와 토구를 이용한 불안정 지지면 운동의 효과 비교)

  • Kim, Min-Kyu;Yang, Hoe-Song;Jeong, Chan-Joo;Kang, Hyo-Jeong;Yoo, Young-Dae
    • Journal of The Korean Society of Integrative Medicine
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    • v.9 no.4
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    • pp.191-200
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    • 2021
  • Purpose : Chronic ankle instability can lead to problems in balance and gait due to weakness of the ankle muscles and decreased proprioceptive sensation. Balance training that stimulates proprioceptors is necessary to improve ankle stability. We aimed to compare the effects of unstable support balance exercises using whole body sonic vibration and an aero-step (TOGU) on proprioception and balance in individuals with unilateral functional ankle instability. Methods : Thirty-six participants with unilateral functional ankle instability were randomly recruited and divided into two groups (group 1 = sonic whole body vibration, group 2= TOGU). Individuals in each group participated in training for 5 weeks, 40 minutes per session, 5 times per week, and performed weight-bearing exercises in five postures on different unstable support surfaces. Proprioception was measured by digital inclinometer (Dualer IQ), and balance was measured by force platform (Biodex balance system). Results : Significant differences were observed in proprioception before and after intervention within both group (p<.05). Significant differences were also observed in the balance index before and after intervention within both groups (p<.05). Conclusion : As a result of this study, it is suggested that for individuals with ankle instability, unstable support surface training using a whole body sonic vibrator and TOGU can have a positive effects on proprioception and balance ability.