• Title/Summary/Keyword: shock wave

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A Literature Review on the Use of Extracorporeal Shock Wave with Syndrome Differentiation Theory (한방 변증 이론에 근거하여 사용된 체외충격파 연구에 대한 문헌 고찰)

  • Lee, Sang-Hyun;Kim, Hyun-Tae;Park, Sun-Young;Heo, In;Hwang, Man-Suk;Shin, Byung-Cheul;Hwang, Eui-Hyoung
    • Journal of Korean Medicine Rehabilitation
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    • v.30 no.2
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    • pp.95-103
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    • 2020
  • Objectives This report aimed to review literatures using extracorporeal shock wave with syndrome differentiation theory. Methods By March 3, 2020, five foreign electronic databases (PubMed, Web of Science, Cochrane Library, EMBASE, CAJ) and six Korean medical electronic databases (KMBASE, KISTI, KISS, NDSL, DBpia, RISS) were reviewed with the key word 'extracorporeal shock wave' and 'syndrome differentiation'. We did not impose restrictions on age, gender, treatment methods, duration, results and the design of the paper. Results Twelve papers met the inclusion criteria. Seven papers used extracorporeal shock wave lithotripsy with syndrome differentiation theory and six out of seven papers treated urologic stones using extracorporeal shock wave lithotripsy. The other five papers used extracorporeal shock wave therapy with syndrome differentiation theory and four of them treated musculoskeletal disorders. However, the data of the characteristics of extracorporeal shock wave was insufficient. Conclusions After thorough review, it is considered to be meaningful to treat urologic stones and musculoskeletal disorders using extercorporeal shock wave with syndrome differentiation theory. However, some of the literatures were limited in their feasibility and reliability in terms of research design. In addition, the data regarding the strength of the extracorporeal shock wave applied on each acupoints was insufficient. Therefore, further study on the use of extracorporeal shock wave on acupoints should be conducted.

Impact of Shock Wave on Nerve Regeneration in Motion Analysis of Affected Side after Nerve Injury (신경 손상 후 환측의 동작분석을 통한 충격파가 신경재생에 미치는 영향)

  • Lee, Jung-Ho;Choi, Yeong-Deok;Sung, Youn-Bum
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.9 no.3
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    • pp.533-540
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    • 2019
  • This study investigated the effect of extracorporeal shock wave therapy on nerve regeneration in nerve injured rats. In this study, we used 30 male Sprague-Dawley rats weighing 230-280g and 6 weeks old. Study groups were divided into two groups using a random sampling method: experimental group (n=15) treated with extracorporeal shock wave after sciatic nerve injury and control group (n=15) treated without extracorporeal shock wave after sciatic nerve injury. In this study, extracorporeal shock wave therapy equipment (OPTIMUS, SALUS TALENT 3, Korea) was used to apply extracorporeal shock wave therapy and applied to the sciatic nerve crush area of the right hind limb using low intensity. We measured the stance time and stride distance of the affected side using dartfish software. There was a statistically significant difference in the change of stance time and stride distance of the affected side between the experimental group using extracorporeal shock wave therapy and the control group without extracorporeal shock wave treatment. In conclusion, extracorporeal shock wave therapy has a positive effect on nerve regeneration.

Numerical Visualization of the Shock Wave System Discharged from the Exits of Two-Parallel Ducts (두 평행한 관 출구로부터 방출되는 충격파시스템의 수치해석적 가시화)

  • Jung Sung Jae;Kweon Yong Hun;Kim Heuy Dong;Kang Chang Soo
    • 한국가시화정보학회:학술대회논문집
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    • 2004.11a
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    • pp.72-75
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    • 2004
  • The present study describes a computational work to investigate detailed behaviors of the twin shock waves discharged from the exits of two-parallel ducts. In computations, the Yee-Roe-Davis's TVD scheme was used to solve the unsteady, three-dimensional, inviscid, compressible, Euler equations. The distance between two ducts is varied and the Mach number of the incident shock wave is changed below 2.0. The results obtained show that on the symmetric axis between two-parallel ducts, the maximum pressure achieved by the merge of twin shock waves and its location strongly depend upon the distance between two-parallel ducts and the Mach number of the incident shock wave. It is also found that the twin shock waves discharged from the exits of two-parallel ducts leads to the complicated flow fields, such as Mach stem, spherical waves, and vertical structures.

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Study on the Characteristics of Impulse Wave Discharged from the Tube Exit with Non-Circular Cross-Section (비원형 관출구로부터 방출되는 펄스파의 특성에 관한 연구)

  • Shin, Hyun-Dong;Kweon, Yong-Hun;Lee, Young-Ki;Kim, Heuy-Dong
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.550-555
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    • 2003
  • When a shock wave arrives at an open end of tube, an impulse wave is discharged from the tube exit and complicated flow is formed near tube exit. The flow field is influenced by the cross-sectional geometry of tube exit, such as circular, square, rectangular, trapezoid and etc. In the current study, three-dimensional propagation characteristics of impulse wave discharged from the tube exit with non-circular cross section are numerically investigated using a CFD method. Total variation diminishing (TVD) scheme is used to solve the three-dimensional, unsteady, compressible Euler equations. Computations are performed for the Mach numbers of the incident shock wave $M_{s}$ below 1.5. The results obtained show that the peak pressure of the impulse wave and propagation directivity depends on the cross-sectional geometry of tube exit and the Mach number of incident shock wave.

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Study of the Open End Correction of the Impulsive Wave Discharging from a Duct Exit (관출구로부터 방출하는 펄스파의 개구단 보정에 관한 연구)

  • 이동훈;김희동
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.11 no.7
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    • pp.239-246
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    • 2001
  • The present study addresses the open correction associated with the reflection and discharge phenomena of a weak shock wave from an open end of a duct. The open correction of the weak shock wave is investigated experimentally and by numerical computation. An experiment is made using a simple shock tube with an open end. and computaion is performed to simulate the experimental flow field using the unsteady, axisymmetric compressible. flow governing equations. The results obtained show the an open correction should be involved for shock wave discharge and reflection problems generated from the exit of the duct with an open baffle plate. With a baffle plate less than three times the duct diameter, it is found that the open end correction is a function of both the diameter of the baffle plate and normal shock wave magnitude However, for a baffle plate larger than three the duct diameter it is independent of the baffle plate diametre, The present computations predict the results of shock tube experiment with good accuracy. A new empirical equation for prediction of the open correction is found for the weak shock reflection and discharge phenomena occurring at the open of the duct with and without a baffle plate.

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Passive control of condensation shock wave in supersonic nozzles (초음속 노즐에서 발생하는 응축충격파의 피동제어)

  • Kim, Hui-Dong;Gwon, Sun-Beom;Setoguchi, Toshiaki
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.12
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    • pp.3980-3990
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    • 1996
  • When a moist air is rapidly expanded in a supersonic nozzle, nonequilibrium condensation occurs at a supersaturation state. Condensation shock wave appears in the nozzle flow if the releasing latent heat due to condensation goes beyond a critical value. It has been known that self-excited oscillations of the condensation shock wave generate in an air or a steam nozzle flow with a large humidity. In the present study, the passive control technique using porous wall with a cavity underneath was applied to the condensation shock wave. The effects of the passive control on the steady and self-excited condensation shock waves were experimentally investigated by Schlieren visualization and static pressure measurements. The result shows that the present passive control is a useful technique to suppress the self-excited oscillations of condensation shock wave.

Effects of supersonic condensing nozzle flow on oblique shock wave (超音速 노즐흐름에 있어서 凝縮이 傾斜衝擊波에 미치는 影響)

  • 강창수;권순범
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.13 no.3
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    • pp.547-553
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    • 1989
  • Last several stages of high capacity fossil power steam turbine and most stages of nuclear power steam turbine operate on wet steam. As a consequence, the flows in those cascades are accompanied by condensation, and the latent heat caused by condensation affects an oblique shock wave being generated at the vicinity of trailing of the blade. In the case of expanding of moist air through a suction type indraft wind tunnel, the effect of condensation affection the oblique shock wave generated by placing the small wedge into the supersonic part of the nozzle was investigated experimentally. In these connections, the relationship between condensation zone and reflection point of the incident oblique shock wave, angle between wedge bottom wall and oblique shock wave, and the variations of angles of incident and reflected shock waves due to the variation of initial stagnation relative humidity are discussed. Furthermore, the relationship between initial stagnation relative humidity and load working on the nozzle wall, obtained by measuring static pressure at the nozzle centerline, is discussed.

An Electromagnetic Shock Wave Generator Employing a Solenoid Coil for Extracorporeal Shock Wave Therapy: Construction and Acoustical Properties (체외 충격파 치료술을 위한 솔레노이드 코일을 이용한 전자기식 충격파 발생기: 구성 및 음향학적 특성)

  • Choi Min Joo;Lee Jong Soo;Kang Gwan Suk;Paeng Dong Guk;Lee Yoon Joon;Cho Chu Hyun;Rim Geun Hie
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.5
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    • pp.271-281
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    • 2005
  • An electromagnetic type shock wave generator suitable for extracorporeal shock wave therapy has been constructed by employing a solenoid coil. The Property of the shock waves produced by the shock wave generator was evaluated using a needle hydrophone. It was shown that, as the capacitor discharging voltage increased from 8 to 18 kV, the Positive Peak Pressure (P+) of the shock wave increased non-linearly from 10 to 77 Wa. In contrast. the negative peak Pressure (f) varied between -3.2 and -6.8 MPa. had its absolute maximum of -6.9 ma at 14 kV The peak amplitudes P+ measured repeatedly under the same voltage setting varied within $5\;\%$ from mean values and this is very small compared to about $50\;\%$ for electrohydraulic type shock wave generators. It could be observed, from the hydrophone signal recorded over 1 ms. several sequential acoustic impulses representing bubble collapses. namely. acoustic cavitation. induced by the shock wave. A technique based on wavelet transformation was used to accurately measure the time delay between the 1st and 2nd collapse known to be closely related to the shock strength. It was observed that the measured time delay increased almost linearly from 120 to $700\;{\mu}s$ with the shock wave Pressure P+ increasing from 10 to 77 MPa.

Extracorporeal Shock Wave Therapy: Its Acoustical Aspects

  • Choi, Min-Joo;Cho, Sung-Chan;Paeng, Dong-Guk;Lee, Kang-Il
    • The Journal of the Acoustical Society of Korea
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    • v.29 no.3E
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    • pp.119-130
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    • 2010
  • Extracorporeal shock wave therapy (ESWT) is simply evolved from extracorporeal shock wave lithotripsy known as a revolutionary non-invasive technique for treating kidney stone diseases. Since ESWT was approved for treating plantar fasciitis by FDA in 2000, it has been rapidly accepted into various clinical practices. Its indication includes chronic tendinitis and pseudoarthrosis, and has been widened to various applications other than orthopeadics. Little has been reported on their acoustic properties, yet, even if a number of clinical ESWT systems are readily available. This article reviews the acoustical aspects of ESWT and discusses critical issues towards acoustic exposure optimization and shock wave dosimetry.

The Impingement of a Weak Shock Wave Discharged from a Tube Exit upon a Flat Plate (관 출구로부터 방출하는 약한 충격파의 평판충돌에 관한 연구)

  • 이동훈;김희동;강성황
    • Journal of KSNVE
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    • v.10 no.6
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    • pp.1035-1040
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    • 2000
  • The Impingement of a weak shock wave discharged from the open end of a shock tube upon a flat plate was investigated using shock tube experiments and numerical simulations. Harten-Yee Total Variation Diminishing method was used to solve axisymmetric, unsteady, compressible flow governing equations. Computations predicted the experimented results with a good accuracy. The peak pressure on the flat plate was not strongly dependent of the shock wave Mach number in the present range of Mach Number from 1.05 to 1.20. The distance between the plate and shock tube was changed to investigate the effect on the peak pressure. From both the results of experiments and computations we obtained a good empirical equation to predict the peak pressure on the flat plate.

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