• Title, Summary, Keyword: pulse ultrasound

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Analysis of Relations Between Physiologic Parameters and Pulse Transit Time on the Ultrasound Therapy (초음파 재활치료 시 PTT와 생리변수의 상관관계 분석)

  • Kim, Sung-Min;Choi, Sang-Hyuk;Lee, Man-Pyo;Choi, Byeong-Cheol;Jung, Whoi-Seong;Park, Sung-Yoon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.8
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    • pp.1514-1520
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    • 2007
  • Currently, the signal of the human body is measured with various methods, and a noninvasive investigation of various methods is useful diagnosis method. PTT(Pulse Transit Time) which is noninvasive investigation make use of to estimate the physiological phenomena. PTT has a latent information of cardiovascular system. So we have the experiments for analysis of the relations between PTT and physiological parameters. We examine to correlate to the physiological parameters, an age and degree of paralysis on the ultrasound therapy. The 40 patients who has a such paralysis join our experiment, and we obtain the PTT data that normal condition and states after ultrasound therapy. We study that PTT after the ultrasound therapy for patients who have a paralysis was related to an age and degree of paralysis.

Simulation of Excitation and Propagation of Pico-Second Ultrasound

  • Yang, Seungyong;Kim, Nohyu
    • Journal of the Korean Society for Nondestructive Testing
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    • v.34 no.6
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    • pp.457-466
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    • 2014
  • This paper presents an analytic and numerical simulation of the generation and propagation of pico-second ultrasound with nano-scale wavelength, enabling the production of bulk waves in thin films. An analytic model of laser-matter interaction and elasto-dynamic wave propagation is introduced to calculate the elastic strain pulse in microstructures. The model includes the laser-pulse absorption on the material surface, heat transfer from a photon to the elastic energy of a phonon, and acoustic wave propagation to formulate the governing equations of ultra-short ultrasound. The excitation and propagation of acoustic pulses produced by ultra-short laser pulses are numerically simulated for an aluminum substrate using the finite-difference method and compared with the analytical solution. Furthermore, Fourier analysis was performed to investigate the frequency spectrum of the simulated elastic wave pulse. It is concluded that a pico-second bulk wave with a very high frequency of up to hundreds of gigahertz is successfully generated in metals using a 100-fs laser pulse and that it can be propagated in the direction of thickness for thickness less than 100 nm.

Analysis of Relations Between Transmission Time of Therapeutic Ultrasound and Pulse Transit Time (치료용 초음파의 투과시간과 PTT의 상관관계 분석)

  • Kim, Sung-Min;Lee, Joo-Hwan;Choi, Byeong-Cheol;Jung, Whoi-Seong;Bae, Ha-Suk
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.12
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    • pp.2345-2350
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    • 2008
  • Recently, ultrasound is becoming a universal way of treatment when it comes to clinic. The thermal effect of therapeutic ultrasound can raise the temperature of tissue without damage and thus increases the flow rate, and this leads to the oxygen transportation velocity of peripheral tissue and ultimately facilitates the metabolism. The purpose of this research is analyzing relations between PTT and transmission time of therapeutic ultrasound, and in this study the PTT variation due to respective transmission time of ultrasound upon 17 normal persons was measured and as a result, it was observed that PTT increases as transmission time of therapeutic ultrasound

Design of Mutually Orthogonal Polyphase Complementary Sequences for Ultrasound Imaging (초음파 영상을 위한 직교 상보수열의 설계)

  • 김배형;김태호;송태경
    • Proceedings of the IEEK Conference
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    • pp.393-396
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    • 2002
  • In this paper, we present a new method for generating a set of complementary sequences that can be simultaneously transmitted and yet compressed into a short pulse on reveive, and its application to ultrasound imaging. This new complementary sequences can be designed based on a filter bank theory. The new complementary sequences can be used to improve the SNR of ultrasound imaging without sacrificing the spatial resolution and frame rate, compared to conventional pulse-echo imaging. Computer simulations are performed to verify the proposed method.

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Defect Detection of Ceramic Heating Plate Using Ultrasound Pulse Thermography (초음파 펄스 서모그라피를 이용한 세라믹 전열 판의 결함 검출)

  • Cho, Jai-Wan;Seo, Yong-Chil;Jung, Seung-Ho;Kim, Seung-Ho;Jung, Hyun-Kyu
    • Journal of the Korean Ceramic Society
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    • v.43 no.4
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    • pp.259-263
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    • 2006
  • The applicability of UPT (Ultrasound Pulse Thermography) for real-time defect detection of the ceramic heating plate is described. The ceramic heating plate with superior insulation and high radiation is used to control the water temperature in underwater environment. The underwater temperature control system can be damaged owing to the short circuit, which resulted from the defect of the ceramic heating plate. A high power ultrasonic energy with pulse duration of 280 ms was injected into the ceramic heating plate in the vertical direction. The ultrasound excited vibration energy sent into the component propagate inside the sample until they were converted to the heat in the vicinity of the defect. Therefore, an injection of the ultrasound pulse wave which results in heat generation, turns the defect into a local thermal wave transmitter. Its local emission is monitored and recorded via the thermal infrared camera at the surface which is processed by image recording system. Measurements were Performed on 4 kinds of samples, composed of 3 intact plates and the defect plate. The observed thermal image revealed two area of crack in the defective ceramic heating plate.

Development of Flexible Ultrasound System for Elastography (탄성 영상법 개발을 위한 유연성 높은 초음파 시스템의 구현)

  • Kim, D.I.;Lee, S.Y.;Cho, M.H.
    • Journal of Biomedical Engineering Research
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    • v.33 no.1
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    • pp.32-38
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    • 2012
  • Recently, several ultrasound imaging techniques for tissue characterization have been developed. Among them, ultrasound elastography is regarded as the most promising modality and has been rapidly developed. One of ultrasound elastography techniques is shear modulus imaging. Normal and cancerous tissues show big difference of shear moduli and they have good image contrast. However shear wave elastography requires more complicated hardware and more computations for image reconstruction algorithm. Therefore new efficient techniques are being developed. In this paper, we have developed a very flexible ultrasound system for elastography experiments. The developed system has capabilities to acquire ultrasound RF data of all channels and generate arbitrary ultrasound pulse sequences. It has a huge amount of memories for RF data acquisition and a simple and flexible pulse generator. We have verified the performance of the system showing conventional B-mode images and preliminary results of elastography. The developed system will be used to verify our own reconstruction algorithm and to develop more efficient elastography techniques.

Modified Piezoelectric Ceramics for Portable Ultrasonic Medical Probe Application (휴대용 의료 초음파 프로브 적용을 위한 압전체 제조 및 특성)

  • Kang, Dong Heon;Chae, Mi Na;Hong, Se Won
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.29 no.8
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    • pp.483-488
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    • 2016
  • Ultrasound imaging by using piezoelectric materials, such as lead zirconium titanate (PZT) has been one of the most preferred modes of imaging in the medical field due to its simple, low cost and non-ionizing radiation in comparison to other imaging techniques. Recently, the market demand for portable ultrasound is becoming larger with applications in developing countries, disaster area, military, and emergency purposes. However, most of ultrasound probes used is bulky and high power consumable, so unsuitable for such applications. In this study, the 3 layered ceramic specimen consisted of 128 pitches of $420{\mu}m$ in width and $450{\mu}m$ in thickness were prepared by using the Ti-rich PZT compositions co-fired at $1,050^{\circ}C$. Their electrical and ultrasound pulse-echo properties were investigated and compared to the single layer specimen. The 3 layered ultrasound probe showed 1.584 V of Vp-p, which is 3.2 times higher than single layered one, implying that it would allow effectively such a portable ultrasound probe system. The result were discussed in terms of higher capacitance, lower impedance and higher dielectric coefficient of the 3 layered ultrasound probe.

A Comparison of the Immediate Effects of Alternate Methods to Medication in Lowering the Blood Pressure in Prehypertensive Patients

  • Moon, Hyun-Ju;Cho, Sung-Hak
    • The Journal of Korean Physical Therapy
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    • v.28 no.3
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    • pp.201-204
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    • 2016
  • Purpose: The purpose of this study was to compare the immediate effects of alternative treatment methods in lowering the blood pressure and pulse of prehypertensive patients. Methods: A total of 48 prehypertensive patients were randomly divided into 4 groups of 12 patients and each group received a different intervention. The control group was made to rest, the heat pack (HP) group received heat pack treatment, the ultrasound (US) group received an ultrasound massage, and the myofascial release (MFR) group received myofascial release. The blood pressure and pulse rate were measured before and after intervention. Results: Following intervention, the patients of the MFR group showed a decrease in systolic pressure, diastolic pressure, and pulse rate. Although blood pressure was similar in all groups, a significant decrease in pulse rate was seen in the MFR group compared to others. Conclusion: The application of MFR was shown to be an effective method for lowering the blood pressure and pulse rate in prehypertensive patients.

Forward-Looking Ultrasound Imaging Transducer : II. Fabrication and Experimental Results

  • Lee, Chankil
    • The Journal of the Acoustical Society of Korea
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    • v.15 no.2E
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    • pp.76-84
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    • 1996
  • The experimental testing results of the large-scale version of a forward-looking ultrasound imaging catheter(FLUIC) are presented, along with the fabrication techniques used, experimental methods, and comparisons of the measured and simulated results. The transducer model is verified by measuring the electrical impedance of the transducer. The pulse width, beamwidth, and the dynamic range for both transmit and pulse-echo response of the fabricated FLUIC are also analyzed. The experimental results conformed its forward-looking imaging capability and the sources of discrepancies between the simulated and experimental beam profiles are addressed.

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Analysis on Code Used in Pulse Compression Method for Improving Resolution of Ultrasound Imaging System (초음파 영상 시스템에서의 해상도 개선을 위한 펄스압축기법에 사용되는 코드에 대한 분석)

  • You, Y.M.;Lee, H.H.;Song, T.K.
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.115-116
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    • 1998
  • Pulse echo techniques have been used for the conventional medical ultrasound imaging systems. However, their resolution is limited in the transmitted signal power. To overcome this limit, pulse compression method used in the radar systems was proposed. This system transmits a continuous coded signal and then compresses the received signal into the short and high resolution pulse by using correlator. The reflectors can be detected by cross-correlation between the transmitted signal and the received signal with the depth information. In this paper, we will present a comparative study of the performances of the most common sequences(pseudo-chirp, m-sequences, modified Golay code). The best result for improving resolution is obtained with the modified Golay Code.

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