• Title/Summary/Keyword: shockwave

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Study on the Performance Evaluation and Supplementations of Extracorporeal Shockwave Therapy (체외충격파 치료기(Extracorporeal Shockwave Therapy)의 성능평가 및 보완사항에 관한 연구)

  • Oh, Chan-Woo;Park, Sang-Geon;Park, Hong-Gyu
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.67 no.1
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    • pp.52-56
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    • 2018
  • Extracorporeal shockwave therapy has been widely spread out showing an excellent efficacy compared to traditional medicinal treatments, interventional procedures or surgeries for diseases of tendons and musculoskeletal system. Major performance tests of extracorporeal shockwave therapy consist of pressure, energy flux, concentration, and effective amount of energy on the focus area of shockwave according to IEC 61846. Shockwave should be irradiated accurately to the lesion area to improve the performance of extracorporeal shockwave therapy, which makes it necessary to add the relevant section, IEC 60601-2-36 (12.1.101. Precision of Target Markers and Target Locations). International standards of extracorporeal shockwave therapy have been prepared based on European and western people. Thus, we need to conduct many studies on Korean patients to improve the quality of extracorporeal shockwave therapy and to develop the medical industry. In addition, the performance evaluation of extracorporeal shockwave therapy which has been prepared according to international standards should be additionally modified and supplemented corresponding to the Korean circumstances.

Backward Moving Shockwave Speed Measurement in Traffic Images (교통 영상에서의 Backward Moving 충격파 속도 측정)

  • 권영탁;소영성
    • Journal of the Institute of Convergence Signal Processing
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    • v.3 no.3
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    • pp.6-13
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    • 2002
  • In this paper, we propose an image processing based method to measure red-time and green-time backward moving shockwave speed automatically at signalized intersections. Shockwave means the discontinuous boundary line between different vehicle traffic flows, and its moving speed is called shockwave speed which is obtain from the slope of boundary line. In this paper, we compose distance-time diagram for measuring shockwave speed automatically. By global vehicle tracking, we draw all of the vehicle moving path on distance-time diagram. We analyze the slope change pattern of curved moving path line, and compute red-time and green-time backward moving shockwave speed. We obtain the measurement result of shockwave speed, when applying above mentioned proposed method to experiment at signalized intersections, Once we can measure the shockwave speed, we could apply the result to highway ramp metering and automatic signal control at intersections effectively since we know the situation of frontal congestion easily.

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A Development of Macroscopic Simulation Model for Interrupted Flow using Shockwave (충격파를 이용한 거시적 단속류 시뮬레이션 모형개발)

  • Lee, Ho-Sang;Jung, Young-Je;Kim, Young-Chan;Kim, Dae-Ho
    • Journal of Korean Society of Transportation
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    • v.26 no.1
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    • pp.191-201
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    • 2008
  • It has been employed TRANSYT-7F and NETSIM to evaluate the validity and effectiveness of improvement on TSM(Transportation Systems Management). But T7F is hard to describe platoon compression and dispersion in actually, and NETSIM takes a long time for network coding, calibration and have difficulty in setting up saturation flow. While Shockwave Model have advantage which can describe platoon compression and dispersion in actually and shorten hours, convenience of application. But Shockwave Model apply unrealistic traffic flow relation ship(U-K curve) and simplify platoon because of difficulty in calculating shockwave's position and cross. For solving limitation of existing shockwave models, It develop new model with 2-regime linear model, New platoon model, Extended shockwave, etc. For verifying the validity of the proposed model, it was compared with delay of T7F and NETSIM by offset variation. In conclusion, it is thought that proposed model have outstanding performance to simulate traffic phenomenon.

Numerical study on the effects of nozzle geometry and substrate location in the supersonic flow (노즐 형상과 기판의 위치 변화가 초음속 유동에 미치는 영향에 관한 수치해석 연구)

  • Park, Jung Jae;Yoon, Suk Goo;Kim, Ho Young
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.06a
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    • pp.58.2-58.2
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    • 2010
  • This paper deals with the simulation of solid particle coating technology via supersonic nozzle in vacuum environment to devote as an aerosol-deposition device. In order to improve efficiencies of nozzle and coating process, effects of shockwave, nozzle geometry, and substrate location were studied computationally under a fixed chamber pressure of 0.01316 bar which is nearly vacuous. Shockwave is the important factor affect to entire flow because shockwave in the jet flow dissipates the kinetic energy of the flow in the supersonic condition. Results show that various nozzle geometries have significant effect on the supersonic flow and we know that the supersonic nozzle should be optimized to minimize the loss of the flow. Another parameter, the distance between substrate and nozzle tip, shows little effect in this study.

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Effect of Shockwave on Diesel Spray Characteristics in Ultra High Pressure Injection (극초고압 디젤분무의 충격파가 디젤분무특성에 미치는 영향)

  • Jeong, Dae-Yong;Lee, Jong-Tai
    • Journal of ILASS-Korea
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    • v.10 no.1
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    • pp.10-16
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    • 2005
  • To investigate the effect of shockwave on diesel spray characteristics under ultra high pressure injection, the velocity of spray tip and shock wave were investigated using the visualization of spray by schlieren method. Spray characteristics such as the spray radius, height, and droplets size were analyzed. It is found in this study that shock wave, produced by ultra high injection pressure, propagates faster than spray tip. Spray radius of right side of nozzle tip was shorter than that of left side and spray height of right side of nozzle tip was thicker than that of left side. Droplets sue was increased at 414MPa in injection pressure because of pressure gradient between inner and outer of tile spray caused by shockwave.

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Simulation of Shockwave Developed by Pulse Discharge (펄스 방전에 의한 충격파 발생 시뮬레이션)

  • Lee, Seung-Rae;Park, Hyun-Ku;Kim, Tae-Hoon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.03a
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    • pp.912-921
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    • 2009
  • Pulse-discharge technology (PDT) is an innovative technology which uses enormous energy developed by electric discharge for a very instant moment of time. Lately, it has been applied to make expanded sections at the ends of piles and anchors. The expanded section is formed by the deformation of bore-hole induced by shockwave energy developed in filling material by the pulse discharge. In this study, considering the phenomenon of pulse-discharge as an underwater explosion, finite element analyses were carried out to model the shockwave development by pulse discharge. The simulation technique was verified by comparing results with underwater discharge test results.

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Shockwave Simulations and Visualization for Teaching Quantum Chemistry (양자화학 교육을 위한 쇽웨이브 시뮬레이션 및 시각화)

  • Lee, Chang-Jae
    • Journal of the Korean Chemical Society
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    • v.53 no.2
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    • pp.166-174
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    • 2009
  • Quantum chemistry has many concepts that are either abstract or counterintuitive, giving students difficulties in understanding them. Fortunately, the advancement of web technologies provides us with hordes of powerful tools to produce rich multimedia web applications that supplement traditional classroom teaching. In this paper we present an approach to address this issue that combines interactive simulations and visualization on the web browser using Shockwave technology. With several examples, we show how to take advantage of the features of the Shockwave technology in developing web-based course material with ease.

Design of Polymer Composites for Effective Shockwave Attenuation (충격파 완화 복합재의 설계)

  • Gyeongmin Park;Seungrae Cho;Hyejin Kim;Jaejun Lee
    • Composites Research
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    • v.37 no.1
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    • pp.21-31
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    • 2024
  • This review paper investigates the use of shockwave attenuating materials within composite structures to enhance personnel protection against blast-induced traumatic brain injury (bTBI). This paper also introduces experimental methodologies exploited in the generation and measurement of shockwaves to evaluate the performance of the shock dissipating composites. The generation of shockwaves is elucidated through diverse approaches such as high-energy explosives, shock tubes, lasers, and laser-flyer techniques. Evaluation of shockwave propagation and attenuation involves the utilization of cutting-edge techniques, including piezoelectric, interferometer, electromagnetic induction, and streak camera methods. This paper investigates phase-separated materials, including polyurea and ionic liquids, and provides insight into composite structures in the quest for shockwave pressure attenuation. By synthesizing and analyzing the findings from these experimental approaches, this review aims to contribute valuable insights to the advancement of protective measures against blast-induced traumatic brain injuries.