• Title/Summary/Keyword: 초음파

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The Directivity Measurement of Angle Probe by Photoelastic Visualization Method (광탄성가시화법에 의한 사각탐촉자의 지향성 평가에 관한 연구)

  • Nam, Y.H.;Date, K.
    • Journal of the Korean Society for Nondestructive Testing
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    • v.14 no.2
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    • pp.83-89
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    • 1994
  • It is important for an ultrasonic testing to know the sound pressure field and the directivity of ultrasonic waves propagating in a solid. The directivity of ultrasonic wave is closely related to the sensitivity, the scanning pitch, the arrangement of angle probe, and the defect kind in ultrasonic testing. This paper describes on the directivity measurement of ultrasonic wave using ultrasonic wave visualization method. The directivity of the shear wave emitted from the angle probes were constant during propagation. The difference of directivity was existed between 2MHz and 4MHz angle probes. The centers of directivity were located backward from the incident poing and inside of the angle probe and were not changed during the wave propagation.

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Ultrasonography of the Elbow Joint (주관절의 초음파 검사)

  • Kim, Chul Hong;Lee, Myung Jin;Kang, Min Soo
    • The Journal of Korean Orthopaedic Ultrasound Society
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    • v.5 no.2
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    • pp.123-129
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    • 2012
  • The purpose of this article is review about the use of ultrasonography in the evaluation of the elbow joint. Ultrasonography has several key advantages in elbow joint, including easy assessment of target structure in elbow joint and ability to perform real time dynamic examination and to compare with opposite site. Ultrasonography is easy available to visualize abnormalities affecting tendons, muscles, ligaments, bursae, and occult fractures around the elbow joint and also allows accurate assessment of ulnar nerve in cubital tunnel. The role of ultrasonography will increase further with regards to evaluation of soft-tissue abnormalities of the elbow joint.

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The Use and Findings of Ultrasound in the Wrist Joint (완관절의 초음파 소견 및 이용)

  • Kim, Jung-Han;Kim, Joo-Yong;Kwon, Yong-Uk
    • The Journal of Korean Orthopaedic Ultrasound Society
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    • v.7 no.2
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    • pp.132-137
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    • 2014
  • We can test for small structures located at the surface layer as high resolution ultrasonic techniques and small probes were developed. Accordingly ultrasound became a useful tool in the diagnosis and treatment of wrist diseases. It is important to understand the anatomical structures and apply clinical features as well as these technical aspects when using ultrasound. The purpose of this article is to evaluate the usefulness and approach of ultrasound about typical diseases according to the area of the wrist pain.

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Prediction of the Failure Stress of Tofu Texture Using a Delay Time of Ultrasonic Wave (초음파의 지연 시간을 이용한 두부 조직의 물성변화 예측에 관한 연구)

  • Kim, Hak-Jung;Hahm, Young-Tae;Kim, Byung-Yong
    • Applied Biological Chemistry
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    • v.38 no.4
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    • pp.325-329
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    • 1995
  • Changes in the physical properties of soybean curd upon the processing conditions such as coagulant concentration, heating temperature and molding pressure were determined by using a failure stress and residual delay time of ultrasonic wave(5 MHz). Maximum failure stress of Tofu was obtained at the 0.3% $CaCl_2$ coagulant concentration, $95^{\circ}C$ heating temperature and greater molding pressure, respectively, whereas the delay time is inverse proportion to the failure stress value. The results of the multiple regression analysis with factorial design showed that the model equation consisted with delay time and processing conditions gave the good prediction of the Tofu failure stress.

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Ultrasound-Guided Regional Nerve Block in Lower Extremity (하지에서의 초음파 유도 국소 신경 차단술)

  • Kang, Chan
    • The Journal of Korean Orthopaedic Ultrasound Society
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    • v.5 no.1
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    • pp.50-59
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    • 2012
  • In the domain of orthopaedic surgery, application of regional nerve block for surgery or pain control in upper and lower extremities has been increased. By performing regional block of popliteal (sciatic), femoral, proximal saphenous nerve and ankle block under guidance of ultrasound, not only the safety, but also success rate of the procedure has increased, and amount of local anesthetics could be used less, too. Since the perineural single injection or continuous catheterization of diluted local anesthetics was performed more precisely and easily by the guidance of ultrasound, postoperative pain could be controlled without complications of PCA such as nausea, vomiting, etc. We will discuss about this ultrasound guided regional nerve block.

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Analysis of Ultrasonic Attenuation for Improving Ultrasonic Burning Rates Measurement of Solid Propellants (고체추진제 초음파 연소속도 측정 정밀도 향상을 위한 초음파 감쇠 분석)

  • Oh, Hyun-Taek;Song, Sung-Jin;Kim, Hak-Joon;Ko, Sun-Feel;Kang, To;Kim, In-Chul;Yoo, Ji-Chang;Jung, Jung-Yong
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2008.05a
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    • pp.195-198
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    • 2008
  • Ultrasonic method is applied for measuring burning rates of the solid propellants, since it can measure burning rates as a function of pressure in a single test performed. However, to replace the stand burner method by the ultrasonic method, it is necessary to verify of its accuracy and reliability. In this study, we investigated the performance of the ultrasonic method for burning rate measurements by comparison to the strand burner results. Furthermore, we investigated the relation between the attenuations of solid propellants and data scattering in the measured burning rates.

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Ultrasonically Enhanced Stabilization of Soft Clay (초음파를 이용한 연약지반 안정화 촉진)

  • Kim, Young-Uk;Kim, Byoung-Il;Song, Young-Karb
    • Proceedings of the Korean Geotechical Society Conference
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    • 2004.03b
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    • pp.684-691
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    • 2004
  • Various researches have been undertaken to develope a method of enhancing consolidation. This study investigated the effect of ultrasound on consolidation through a series of laboratory experiments. The tests were conducted using a specially designed and fabricated equipments which can apply ultrasonic energy on a soil sample at consolidation test. Specimens were prepared using a centrifuge facility, and test conditions included ultrasonic power and treatment time. The results of the study show that the effect of ultrasonic energy on consolidation is significant. The degree of significance varies with the test conditions. It could be concluded that the study showed potential application of ultrasound to enhance consolidation.

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A Study on Propagation of Guided Waves in a Steam Generator Tube (증기발생기 세관에서의 유도초음파 전파에 관한 연구)

  • 송성진;박준수;김재희;김준영;김영환
    • The Journal of the Acoustical Society of Korea
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    • v.23 no.5
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    • pp.353-361
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    • 2004
  • Propagation of the guided waves in a steam generator (SG) tube was investigated. Dispersion curves and the incident angles corresponding to the specific modes were calculated for the SG tube. The modes of guided wave were identified by time-frequency diagrams obtained by short time Fourier transform. Group velocities were also determined from the time-frequency diagrams obtained at the different separations of transducers. In experiment. distinct mode conversion was not observed when the guided ultrasound passed curved region of the S/G tube. The optimum mode of guided wave for the inspection of SG tube was suggested and verified by experiments.

Musculoskeletal Ultrasound Intervention: Principles & Cautions (초음파를 이용한 침습적 치료: 원칙과 주의점)

  • Oh, Gun-Myung;Lee, Kyung Jae;Min, Byung-Woo;Kim, Dong-Wan
    • The Journal of Korean Orthopaedic Ultrasound Society
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    • v.6 no.1
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    • pp.38-44
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    • 2013
  • The ultrasound can be used primarily to guide exact needle placement for aspirations of fluids, injections of steroid, and biopsies in musculoskeletal field. Recently, ultrasound-guided intervention is widely used because of several advantages such as real-time performance, relatively inexpensiveness, and getting multiple images without additional radiations. However, the modality is operator dependent and requires detailed knowledge of the relevant anatomy and there have been also reported serious complications related to the procedure. So, authors will discuss about the basic techniques, principles and cautions for the use of ultrasound-guided intervention in musculoskeletal field.

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Appendicitis Extraction of Abdomen Ultrasonographic Images using Facia (근막을 이용한 복부 초음파 영상에서 충수염 추출)

  • Park, Seung-Ik;Song, Doo Heon;Kim, Kwang-Baek
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.11
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    • pp.2382-2387
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    • 2012
  • In this paper, we propose a new method to extract and analyze appendicitis from abdomen ultrasonographic image in order to measure the thickness of appendix and change of inflammation correctly. Since the ultrasonographic image has environmental effect in nature, we standardize the image first and the process of extracting appendicitis then extracts the bottom facia which has the critical role to find appendix area. The experiment with real appendicitis patient verifies that the proposed method is more effective than current field expert's naked eye inspection.