• Smart Structures and Systems
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• v.22 no.2
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• pp.223-230
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• 2018

This study examines a non-contact laser scanning-based ultrasound system, called an angular scan pulse-echo ultrasonic propagation imager (A-PE-UPI), that uses coincided laser beams for ultrasonic sensing and generation. A laser Doppler vibrometer is used for sensing, while a diode pumped solid state (DPSS) Q-switched laser is used for generation of thermoelastic waves. A high-speed raster scanning of up to 10-kHz is achieved using a galvano-motorized mirror scanner that allows for coincided sensing and for the generation beam to perform two-dimensional scanning without causing any harm to the surface under inspection. This process allows for the visualization of longitudinal wave propagation through-the-thickness. A pulse-echo ultrasonic wave propagation imaging algorithm (PE-UWPI) is used for on-the-fly damage visualization of the structure. The presented system is very effective for high-speed, localized, non-contact, and non-destructive inspection of aerospace structures. The system is tested on an aluminum honeycomb sandwich with disbonds and a carbon fiber-reinforced plastic (CFRP) honeycomb sandwich with a layer overlap. Inspection is performed at a 10-kHz scanning speed that takes 16 seconds to scan a $100{\times}100mm^2$ area with a scan interval of 0.25 mm. Finally, a comparison is presented between angular-scanning and a linear-scanning-based pulse-echo UPI system. The results show that the proposed system can successfully visualize defects in the inspected specimens.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3555-3559
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• 2014

Background: The triple-negative breast cancer (TNBC) is an aggressive cancer characterized by the absence of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2). Preoperative mammography and ultrasound features of TNBC may potentially suggest characteristics of the disease and assist in treatment decisions. Materials and Methods: The study covered 153 patients with TNBC from May 2011 to May 2012 who were confirmed by postoperative pathology results in our hospital. We compared the radiological findings among the patients and sought to determine the significant iconographic features. The biomarkers p53 and Ki-67 are regarded as significant factors in TNBC. They were therefore used to divide the TNBC into four groups for assessment of relationships with TNBC imaging features. Results: On mammography, most TNBCs exhibit obscure (44.3%) masses. On ultrasound, the majority of masses (95.4%) were predominantly indistinct (50.7%), irregular (76.0%) or featuring posterior echo enhancement/shadowing. Color Doppler flow imaging (CDFI) emphasized hypervascular (32.9%) masses. Differences in CDFI by ultrasound among the four groups were statistically significant (p=0.009). There were obvious differences in the percentages of spiculated margin (p=0.049) and intensive posterior echo (p=0.006) with spotty flow imaging by ultrasound between the Ki-67 (+) p53 (+) and other groups. Conclusions: A combination of mammography and ultrasound revealed the imaging characteristics of TNBC included an obscure mass with less attenuated posterior echoes and some vascularity. A worse prognosis was associated with spiculated margin and intensive posterior echoes with spotty flow imaging.

• Journal of radiological science and technology
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• v.26 no.1
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• pp.51-62
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• 2003

We carried out studies on develop of the ultrasound tissue mimicking materials(TMM) by synthesis of polymer urethane(C, CCR, $TiO_2$, tungsten, graphite, silver type). The major finding were as follows; (1) C type TMM was shown good homogeneity, penetration, gray scale like as liver tissue and propagated speed 1,540 m/s, attenuation $0.5{\sim}0.7\;dB/cm/MHz$. (2) $TiO_2$ type TMM was shown heterogeneous dot echo pattern. (3) Silver type TMM was appear good homogeneous echo pattern like as echo texture of thyroid gland. Therefor, C type TMM will be useful for ultrasound Q/A phantom materials and previous phantom materials.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.391-394
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• 1997

In this paper, we considered newly the use of wavelet transform in order to improve the troubles of the established methods for the analysis of ultrasound echo signals. We made the phantoms of 13.2g, 19.8g, 26.4g, 33.0g, 39.8g by ourselves, and extracted the only pulse-echo signals that reflected through the mediums using windowing technique. For determining the characterized value, the signals were wavelet transformed, absoluted, and integral calculated. As the result, we acquired characterized value of each signals, and acknowledged the differences among them except of some datas. But this will be improved by advanced work as sellecting a proper mother wavelet, a method of making phantoms, correcting the various errors, etc. We expect that wavelet transform is powerful for analysis of ultrasound signals.

• Clinical Pain
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• v.19 no.2
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• pp.64-69
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• 2020

Ultrasound (US) imaging is an efficient, easy to use, rapid, dynamic, noninvasive, with rare side-effects and inexpensive tool allowing for facilitated diagnosis and management of the painful shoulder. It also has advantages over other imaging modalities in the evaluation of the postoperative shoulder for rotator cuff integrity and correct anchor and suture placement, as well as rotator cuff analysis following repair surgery. Early postoperative tendons frequently had a hypo- echoic echo texture and the absence of a fibrillar pattern, which might be misinterpreted as recurrent tears. however, these features often normalized into tendons with an increased echo texture and the reappearance of a fibrillar pattern at 6 months. Based on these sequential findings, the US findings within 3 months after surgery should be interpreted with caution to accurately understand and monitor the repaired tendon status.

• Journal of the Korean Society of Radiology
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• v.15 no.6
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• pp.883-889
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• 2021

This study was conducted on 101 patients who visited hospital for abdominal ultrasonography from May 2020 to December 2020. The purpose of this study was to find out the elasticity according to the ultrasound images (echo pattern, splenomegaly, hepatitis) during the ultrasound examination using the shear wave elastography. The shear wave elastography value of the normal group of the echo pattern was 5.75±1.58 kPa, and the group with the abnormal echo pattern was 8.84±4.94 kPa, and the shear wave elastography value of the abnormal group was high (p<0.05). In normal spleen size, hepatic elasticity value was 6.33±2.54 kPa, and hepatic elasticity value of splenomegaly was 13.73±5.48 kPa. In the case of splenomegaly, the liver elasticity value was high, and there was a statistically significant difference (p<0.05). As the spleen size increased, the liver elasticity value increased by 1.485 times, and as hepatitis progressed, the liver elasticity value increased by 1.573 times (p<0.05). As a result of analysis of concordance between ultrasound imaging findings and shear wave elastography, the Kappa value was found to be as high as 0.922 (p<0.05), which showed high concordance between the two test methods. Additional comparisons of liver elasticity values in shearwave elastography tests along with liver ultrasound findings are thought to be of great help in diagnosing liver fibrosis.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9C
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• pp.876-883
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• 2003

In this paper, we propose an algorithm for organ recognition in ultrasound images using log power spectrum. The main procedure of the algorithm consists of feature extraction and feature classification. In the feature extraction, as a translation invariant feature, log power spectrum is used for extracting the information on echo of the organs tissue from a preprocessed input image. In the feature classification, Mahalanobis distance is used as a measure of the similarity between the feature of an input image and the representative feature of each class. Experimental results for real ultrasound images show that the proposed algorithm yields the improvement of maximum 30% recognition rate than the recognition algorithm using power spectrum and Euclidean distance, and results in better recognition rate of 10-40% than the recognition algorithm using weighted quefrency complex cepstrum.

• Proceedings of the IEEK Conference
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• 2002.06d
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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.

• Journal of Animal Science and Technology
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• v.65 no.2
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• pp.365-376
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• 2023

Pig breeding management directly contributes to the profitability of pig farms, and pregnancy diagnosis is an important factor in breeding management. Therefore, the need to diagnose pregnancy in sows is emphasized, and various studies have been conducted in this area. We propose a computer-aided diagnosis system to assist livestock farmers to diagnose sow pregnancy through ultrasound. Methods for diagnosing pregnancy in sows through ultrasound include the Doppler method, which measures the heart rate and pulse status, and the echo method, which diagnoses by amplitude depth technique. We propose a method that uses deep learning algorithms on ultrasonography, which is part of the echo method. As deep learning-based classification algorithms, Inception-v4, Xception, and EfficientNetV2 were used and compared to find the optimal algorithm for pregnancy diagnosis in sows. Gaussian and speckle noises were added to the ultrasound images according to the characteristics of the ultrasonography, which is easily affected by noise from the surrounding environments. Both the original and noise added ultrasound images of sows were tested together to determine the suitability of the proposed method on farms. The pregnancy diagnosis performance on the original ultrasound images achieved 0.99 in accuracy in the highest case and on the ultrasound images with noises, the performance achieved 0.98 in accuracy. The diagnosis performance achieved 0.96 in accuracy even when the intensity of noise was strong, proving its robustness against noise.

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.347-354
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• 2014

Korea Central Cancer Registry reported in 2011 that the prevalence rate of thyroid cancer was about 19.6% (the highest) in both men and women. The ratio of thyroid cancer, among cancers that women suffer from, was about 31.1%, the highest among female cancers and about five times more than men. Regarding the incidence of thyroid cancer by age group, the crude rate was highest in women and men aged 15~34. From these figures it can be inferred that there is a greater relationship between thyroid cancer and hormones compared with other cancers. Therefore, young women aged 20~25, even if they are in full health, should undergo a medical examination. This study is aimed at examining changes in thyroid gland detected through self evaluation tests and the analysis of ultrasound screening images in persons aged 20~25. According to the study, 213 persons (about 46.6%) out of 457 people who took part in the study had abnormal echo patterns. With regard to women's abnormal patterns, about 73.4% of them were found to have calcified cystic, 11.8% diffuse-type low-echo and 7.3% cystic echo. With regard to male participants, about 61.1% were found to have calcified cystic, followed by 19.4% with the size of the isthmus increased and 13.9% with diffuse-type low-echo. According to the outcomes of an analysis regarding self-testing for hyperthyroidism, the average points of participants who were found to have abnormal echo patterns in ultrasound tests were 6.85 and the figure was 5.88 in persons with normal patterns. The figure was about 15% higher in abnormal respondents.