• Journal of Mechanical Science and Technology
• /
• v.16 no.3
• /
• pp.292-301
• /
• 2002

Ultrasound waves interact strongly with the orientation and sequence of the plies in a layup when propagating in the thickness direction of composite laminates. Also the layup orientation greatly influences its properties in a composite laminate. If the layup orientation of a ply is misaligned, it could result in the part being rejected and discarded. Now, most researchers cut a small coupon from the waste edge and use a microscope to optically verify the ply sequences on important parts. This may add a substantial cost to the production since the test is both labor intensive and performed after the part is cured. A nondestructive technique would be very beneficial, which could be used to test the part after curing and requires less time than the optical test. Therefore we have developed, reduced, and implemented a novel ply-by-ply vector decomposition model for composite laminates fabricated from unidirectional plies. This model decomposes the transmission of a linearly polarized ultrasound wave into orthogonal components through each ply of a laminate. High probability is found, by comparisons between the model and tests, in characterizing cured layups of the laminates by using the proposed method.

• Journal of the Korean Society of Physical Medicine
• /
• v.8 no.2
• /
• pp.231-238
• /
• 2013

PURPOSE: The purpose of this study is to find out the thickness variation of the superficial and deep abdominal muscles by measuring the thickness of the abdominal muscles. METHODS: 35 young, healthy adults(24 mens and 11 womens) participated in this study. The first, when only bridge exercise we had measured the thickness of their abdominal muscles by the ultrasound. The second, when the abdominal drawing-in during maintaining the bridge exercise we had measured the thickness of their abdominal muscles by the ultrasound. A pared t-test was used to determine a statistical significance for the thickness variation of the superficial and deep abdominal muscles. RESULTS: Results of before and after comparative analysis. The surperficial muscles(rectus abdominis, external obilique) statistically significantly reduced in the thickness and the deep muscle(transeverse abdominis) statistically significantly increased in the thickness. CONCLUSION: We have shown that the abdominal drawing-in exercise during maintaining the bridge exercise was effective to increase in strengthening abdominal deep muscle selectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.29 no.4
• /
• pp.292-300
• /
• 1993

Acoustical imaging has made brilliant progress in the medical science field, and has also made much progress in the nondestructive testing and under water acoustics applications since doctor Dussik brother has studied about possibilities of making images of brain by recording variations in the intensity of ultrasonic beam from head in 1937. In this paper an acoustical image is reconstructed with the power spectra analysed by impulse ultrasound wave generated by electrodynamic transducer(EDT). The EDT generates the impulse ultrasound of 77KHz in center frequency and 120KHz in bandwidth at -20dB by 1200V exciter in this experiment. The impulse ultrasound has the dominant frequency components of 47KHz, 177KHz, 110KHz and 155KHz. The U shape object is adopted in making an acoustical image. The resulted spectral acoustical images are different from the optical view of the U shape object. However the image reconstructed from 110KHz spectrum is very similar to the original optical shape of the object. Even KHz level impulse sound of 70$\mu$sec pulse width is found to be useful in reconstructing acoustical imaging improvement.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.34 no.6
• /
• pp.457-466
• /
• 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.

• Food Engineering Progress
• /
• v.13 no.1
• /
• pp.32-37
• /
• 2009

Central composite design was applied for the ultrasound-assisted extraction from peel and seed of Campbell Early grapes and the extraction processes were optimized for the antiradical activities of the extracts by using response surface methodology. Optimal conditions were 53.45% of ethanol concentration, 45.99${^{\circ}C}$ of extraction temperature and 23.93 min of extraction time for the maximum antiradical activity of grape peel extract (54.98%) and 53.14% of ethanol 56.03${^{\circ}C}$ of temperature and 29.03 min of time for maximum antiradical activity of grape seed extract (90.60%).

• Bulletin of Food Technology
• /
• v.23 no.3
• /
• pp.392-399
• /
• 2010

최근 초음파(ultrasound, US) 기술의 원리와 응용, 특히 식품의 생리활성물질에 관련된 응용기술에 대하여 기술하였다. 간단한 초음파 기술은 제외하고, 유화, 용해, 조직개선, 균질화(homogenization), 점도, 추출, 건조, 결정화, 거품제거(defoaming) 등의 기술에 관한 것이다. 특히 초음파에 의한 추출(UAE)을 상세히 기술하였다. 오늘날 초음파 기술은 생리활성물질의 추출 같은 산업화에 응용되고 있으며, 기능성을 강화하기 위한 추출에도 이용하고 있다. 이러한 초음파 기술은 장래 효과적인 식품기술이 될 것이며, 또한 식품의 성질을 이해하는 데 도움이 될 것이다.

• Parasites, Hosts and Diseases
• /
• v.60 no.6
• /
• pp.409-411
• /
• 2022

Axillary lymph node schistosomiasis is a form of ectopic schistosomiasis, in which the Schistosoma adult worms or eggs are infected in the axillary lymph nodes. A 53-year-old woman visited our hospital with a small mass in the right armpit, which had been present for over 1 month. Histological examination of biopsy samples from the right axillary lymph nodes revealed granulomas containing calcified Schistosoma eggs. This is the first authentic case of ectopic schistosomiasis identified in the axillary lymph nodes.

• Korean Journal of Ecology and Environment
• /
• v.40 no.2
• /
• pp.244-253
• /
• 2007

In this study, mortality, body wet weight, health assessment, and short-term behavioral mode were observed to determine the effects of ultrasound on the ecological response of the carp Cyprinus carpio. Mortality in the treatments was less than 5% during ultrasound exposure (31 dB re 1 ${\mu}Pa$, $14{\sim}15$ kHz) and there were no significant differences among the replicates (P>0.05). The treatments, based on mean wet weight, exhibited greater effect than the controls, but the magnitude of the differences was not large. Skins and tail fins of some test animals exposed to the controls and intensive treatment groups had light injury such as hemorrhaging, whereas, damages in other organs such as eyes, other fins, parasites, thymus, and gills were not observed (P>0.05). Sudden stimuli in low intensity at a short distance caused a directional avoidance of the fish from the sound. However, the carp exposed to ultrasound at the large scale field was not observed clear behavior changes. Overall results suggest that fish exposed to the low-intensity ultrasound had no serious stress during the tests.

• Korean Journal of Food Science and Technology
• /
• v.43 no.3
• /
• pp.321-328
• /
• 2011

Edible films were developed from jujube (Zizyphus jujube Miller) using depolymerization processes of ultrasound and high-pressure homogenization. A 4.6% (w/w) jujube hydrocolloid was treated by ultrasound (600W, 20 min) or homogenized at high pressure (172 MPa, 6 s) and mixed with whey protein isolate, glycerol, xanthan, and sucrose esters of fatty acids to form film-forming solutions from which films were formed by drying. The film prepared by highpressure homogenization (HPH film) produced more homogeneous films without particles than those prepared without depolymerization or with the ultrasound treatment. HPH films possessed the highest tensile strength (4.7MPa), the lowest water vapor permeability ($2.9g{\cdot}mm/kPa{\cdot}h{\cdot}m^2$), and the most uniform and dense microstructures among the films. Flavor profiles of jujube powder and the films were distinguishable. Heat seal strength and oxygen permeability of the HPH films were 44.4 N/m and $0.025mL{\cdot}{\mu}m/m^2$/day/Pa, respectively. Antioxidant activities of jujube power and HPH films were not significantly different.

• Journal of radiological science and technology
• /
• v.41 no.3
• /
• pp.231-240
• /
• 2018

Automated breast ultrasound (ABUS) equipment is a new innovative technique for 3D automatic breast scanning, but limited for the examination in the concave axillary region. The purpose of this study was to determine feasible candidate materials for the ultrasonic wave propagation media in ABUS, enabling the evaluation of the axillary region. Ultrasonography was performed using an ABUS system ($Invenia^{TM}ABUS$, GE, USA) on the ultrasound-specific phantom (UC-551M-0.5, ATS Laboratories, USA) covered by different candidate materials. The validity of feasible candidate materials was evaluated by image quality. Three independent radiological technologists, with more than 10 years of experience, visually assessed on the images. The inter-observer agreements according to the candidate materials were tested using Cronbach's alpha. Unenveloped solidified carrageenan can be a feasible material for the use of ABUS with excellent test reliability. Therefore, the coverage of the axillary region with carrageenan may be effective for ABUS which was originally developed for the convex anatomic structure as female breast.