• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.513-519
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• 2019

Typically, contaminated sediments cause clogging of the drain pipe, which increases the residual water pressure in the drain pipe; this study constructed a system for improving drainage efficiency of tunnels by reducing physical and chemical obstructions through ultrasonic energy generated by a PVDF film. The developed hybrid drainage system utilized a PVDF material film fused with an existing drainage tunnel and maintenance system resulting in the ability to initialize the reverse piezoelectric effect, which was evaluated through an on site application. In order to investigate the maintenance performance of the tunnel drainage system, contaminated sediments were simulated in a drainage pipe to test the effect of ultrasonic conditions on drainage efficiency in the laboratory. As a result of applying the developed portable equipment, the ultrasonic energy was generated for about 20 minutes resulting in a reduction of 74.62% of the contaminated sediments and improving drainage efficiency. From the tunnel, acoustic pressure measurements were taken to calculate the response rate while taking into account the laboratory results. In addition, PVDF film was attached to the transverse and longitudinal side of the drainage pipes where contaminated sediments occur most often in the field tunnel. these calculations show contaminant removal was 90% effective.

• Journal of the Korean Society of Radiology
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• v.16 no.7
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• pp.975-984
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• 2022

Since a linear transducer has an area of interest equal to the length of the transducer, the area of interest can be expanded using the virtual convex function installed in the device.However, it was thought that the change in the direction of the ultrasonic sound velocity according to the change in the visual area of interest would affect the image quality, so this was objectively confirmed. For this study, image evaluation and SNR·CNR of the phantom for ultrasound quality control were measured. As a result, in the phantom image evaluation, both images were able to identify structures in functional resolution, grayscale, and dynamic range. However, it was confirmed that the standard image was excellent in the reproducibility of the size and shape of the structure. As a result of SNR·CNR evaluation, SNR·CNR of most trapezoidal images was low, except for structures at specific locations. In addition, through the statistical analysis graph, it was further confirmed that the SNR and CNR for each depth decreased as the size of the cystic structure decreased. Through this study, it was confirmed that the use of the function has the advantage of providing a wide visual area of interest, but it has an effect on the image quality. Therefore, when using the virtual convex function, it is judged that the examiner should use it in an appropriate situation and conduct various studies to acquire high-quality images and to improve the understanding and proficiency of the equipment.

• Journal of the Korean Society of Radiology
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• v.17 no.6
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• pp.919-927
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• 2023

Elastography utilizes the fact that the tissue of a malignant tumor is harder than that of a benign tumor and increases the specificity of diagnosis according to the elastic modulus of the tumor, helping to reduce unnecessary biopsies. However, the reliability of elastography can be influenced by the equipment used and the examiner's skills. In this study, the researchers analyzed the reproducibility of elastography by evaluating phantom images when measuring the elasticity values repeatedly. Phantoms were created using silicone and gelatin with different levels of stiffness, and they were inserted at varying depths from the surface. The elasticity values were measured using shear wave elastography. The study aimed to determine whether the reproducibility of elasticity values remains consistent depending on the stiffness and depth of the lesions. The experimental results showed that there was no statistically significant correlation between the elasticity values obtained through shear wave elastography and the depth or stiffness of the lesions. However, in the lesions with the lowest stiffness, the elasticity values were statistically significant (p<0.001) and showed a high correlation with the depth of the lesions. Although there were variations in the measured elasticity values based on the differences in lesion stiffness and depth, these differences did not significantly impact the diagnosis. Therefore, shear wave elastography remains a reliable diagnostic method, and it is suggested that it can be helpful in the diagnosis of breast lesions.

• The Journal of Korean society of community based occupational therapy
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• v.10 no.1
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• pp.31-38
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• 2020

Objective : The purpose of this study is to investigate the effects of bilateral chewing exercise applied for 6 weeks on occlusion force and masseter muscle thickness in the elderly living in the community. Methods : This study recruited 25 community residents. All participants performed bilateral chewing exercise using equipment developed for the purpose of oral chewing exercise. The chewing exercise was divided into isometric and isotonic type and applied for about 20 minutes a day, five times a week for six weeks. For the evaluation, the masseter muscle thickness and the maximum occlusion force were measured three times at three week intervals using a portable ultrasound instrument and an occlusion force gauge. Results : As a result of the change in masseter muscle thickness, baseline, 3 weeks later, and 6 weeks later referred to 7.51±0.43, 7.63±0.44, and 7.83±0.46, respectively (F=3.819, p<.05). The post hoc test resulted in a significance between baseline and 6 weeks later (p=0.023). Similarly, as a result of the change in occlusion force, baseline, 3 weeks later, and 6 weeks later referred to 265±9.22, 268±9.57, and 271.59±10.16, respectively (F=3.031, p<.05). The post hoc test resulted in a significance between baseline and 6 weeks later (p=0.048). Conclusion : This study confirmed that bilateral chewing exercise was effective for increasing masseter muscle thickness and occlusion force in the elderly. Therefore, bilateral chewing exercise can be applied as a therapeutic exercise method for improving oral function.

• Journal of Trauma and Injury
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• v.23 no.2
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• pp.107-112
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• 2010

Purpose: Recently, the change to a more complex social structure has led to an increased frequency of traumas due to violence, accident and so on. In addition, the severity of the traumas and the frequency of penetrating injuries have also increased. Traumas to cervical and abdominal areas, what are commonly seen by general surgeons, can have mild to fatal consequences because in these areas, various organs that are vital to sustaining life are located. The exact location and characteristics of the injury are vital to treating patients with the trauma to these areas. Thus, with this background in mind, we studied, compared, and analyzed clinical manifestations of patients who were admitted to Wonju Christian hospital for penetrating injuries inflicted by themselves or others. Methods: We selected and performed a retrospective study of 64 patients who had been admitted to Wonju Christian Hospital from January 2005 to December 2009 and who had cervical or abdominal penetrating injuries clearly inflicted by themselves or others. Results: There were 51 male (79.7%) and 13 female (20.3%) patients, and the number of male patients was more dominant in this study, having a sex ratio of 3.9 to 1. The range of ages was between 20 and 86 years, and mean age was 43.2 years. There were 5 self-inflicted cervical injuries, and 19 self-inflicted abdominal injuries, making the total number of self-inflicted injury 24. Cervical and abdominal injuries caused by others were found in 11 and 29 patients, respectively. The most common area involved in self-inflicted injuries to the abdomen was the epigastric area, nine cases, and the right-side zone II was the most commonly involved area. On the other hand, in injuries inflicted by others, the left upper quadrant of the abdomen was the most common site of the injury, 14 cases. In the neck, the left-side zone II was the most injured site. In cases of self-inflicted neck injury, jugular vein damage and cervical muscle damage without deep organ injury were observed in two cases each, making them the most common. In cases with abdominal injuries, seven cases had limited abdominal wall injury, making it the most common injury. The most common deep organ injury was small bowel wounds, five cases. In patients with injuries caused by others, six had cervical muscle damage, making it the most common injury found in that area. In the abdomen, small bowel injury was found to be the most common injury, being evidenced in 13 cases. In self-inflicted injuries, a statistical analysis discovered that the total duration of admission and the number of patients admitted to the intensive care unit were significantly shorter and smaller, retrospectively, than in the patient group that had injuries caused by others. No statistically significant difference was found when the injury sequels were compared between the self-inflicted-injury and the injury-inflicted-by-others groups. Conclusion: This study revealed that, in self-inflicted abdominal injuries, injuries limited to the abdominal wall were found to be the most common, and in injuries to the cervical area inflicted by others, injuries restricted to the cervical muscle were found to be the most common. As a whole, the total duration of admission and the ICU admission time were significantly shorter in cases of self-inflicted injury. Especially, in cases of self inflicted injuries, abdominal injuries generally had a limited degree of injury. Thus, in our consideration, accurate injury assessment and an ideal treatment plan are necessary to treat these patients, and minimally invasive equipment, such as laparoscope, should be used. Also, further studies that persistently utilize aggressive surgical observations, such as abdominal ultrasound and computed tomography, for patients with penetrating injuries are needed.

• Journal of Internet Computing and Services
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• v.25 no.1
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• pp.99-107
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• 2024

Along with economic growth and industrial development, there is an increasing demand for various electronic components and device production of semiconductor, SMT component, and electrical battery products. However, these products may contain foreign substances coming from manufacturing process such as iron, aluminum, plastic and so on, which could lead to serious problems or malfunctioning of the product, and fire on the electric vehicle. To solve these problems, it is necessary to determine whether there are foreign materials inside the product, and may tests have been done by means of non-destructive testing methodology such as ultrasound ot X-ray. Nevertheless, there are technical challenges and limitation in acquiring X-ray images and determining the presence of foreign materials. In particular Small-sized or low-density foreign materials may not be visible even when X-ray equipment is used, and noise can also make it difficult to detect foreign objects. Moreover, in order to meet the manufacturing speed requirement, the x-ray acquisition time should be reduced, which can result in the very low signal- to-noise ratio(SNR) lowering the foreign material detection accuracy. Therefore, in this paper, we propose a five-step approach to overcome the limitations of low resolution, which make it challenging to detect foreign substances. Firstly, global contrast of X-ray images are increased through histogram stretching methodology. Second, to strengthen the high frequency signal and local contrast, we applied local contrast enhancement technique. Third, to improve the edge clearness, Unsharp masking is applied to enhance edges, making objects more visible. Forth, the super-resolution method of the Residual Dense Block (RDB) is used for noise reduction and image enhancement. Last, the Yolov5 algorithm is employed to train and detect foreign objects after learning. Using the proposed method in this study, experimental results show an improvement of more than 10% in performance metrics such as precision compared to low-density images.

• Journal of Veterinary Clinics
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• v.12 no.1
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• pp.861-876
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• 1995

This study was carried out to get fundamental information about the normal ultrasonogram of the liver and heart in Korean native cattle and calves. The interventricular septum, left ventricular internal diameter, left ventricular free wall thickness, aortic diameter, left atrial diameter, and right ventricular internal diameter of hear in 10 Korean native calves were determined at 4-5 right intercostal spare by use of ultrasonography. The caudal vena cava, portal vein, gallbladder, liver of 9 Korean native cattle and 10 calves were determined at 12, 11 and 10th intercostal spares by use of ultrasonography. Cursor-directed M-mode and gray-scale, B-mode ultrasonograms were obtained with electronic scanning ultrasound equipment with a 3.5 or 5.0-MHz convex transducer. The results obtained through the experiments were summarized as follows: 1. The result of ultrasonographic examination of the korean native calves' heart 1) Interventricular septum in systole and diastole was 1.23 and 0.81 cm, respectively(vc=28.84, 17.4). 2) Ventricular internal diameter in systole and diastole was 2.50 and 4.91 cm, respectively(vc=17.44, 12.73). 3) Left ventricular free was thickness in systole and diastole was 1.44 and 0.92 cm, respectively(vc=26.85, 23.54). 4) Aortic diameter was 2.69.m, .rspectevely(vc=11.29). 5) Left atrial diameter was 1.82 cm(vc=15.31). 6) Right ventricular internal diameter in systole and diastole was 1.12 and 1.9 cm, respectively(vc=33.71, 24.43). 3. Ultrasonographic measurments of caudal vena cava, portal vein, gallbladder of Korean native calves 1) Dorsal margin of caudal vena cava at the 12, 11 and 10th intercostal space was 13.5, 15.3 and 18.1 cm, respectively(p<0.01). 3) Depth of caudal vena cava at the 12, 11 and 10th intercostal space was 4.4, 4.5 and 4.6 cm, respectively. 3) Diameter of caudal vena cava at the 12, 11 and 10th intercostal space was 11.6, 1.7 and 1.6 cm, respectively. 4) Dorsal margin of portal vein at the 12, 11 and 10th intercostal space was 16.2, 18.6 and 21.4 cm, respectively(p<0.01) 5) Depth of portal vein at the 12, 11 and 10th intercostal spare was 4.5, 4.4 and 3.9 cm respectively. 6) Diameter of portal vein at the 13, 11 and 10th intercostal space was 2.1, 2.2 and 1.9 cm respectively. 7) Dorsal margin of gallbladder at the 11 and 10th intercostal space was 23.6 and 23.9 cm, respectively(p<0.01), 8) Longitudinal diameter of gallbladder at the 11 and 10th intercostal space was 7.1 and 5.9 cm, respectively(p<0.05). 9) Transverse diameter of gallbladder at the 11 and 10th intercostal space was 2.4 and 2.1 cm respectively(p<0.01). 3. Ultrasonographic measurments of caudal vena cava, portal vein, gallbladder of Korean native cattle 1) Dorsal margin of caudal vena cava at the 12 and 11th intercostal space was 22.2, and 25.4 cm, respectively(p<0.01). 2) Depth of caudal vena cava at the 12 and 11th intercostal space was 103 and 11.1 cm, respectively(p<0.01). 3) Diameter of caudal vena cava at the 12 and 11th intercostal space was 3.1 and 3.0 cm, respectively. 4) Dorsal margin of portal vein at the 12 and 11th intercostal space was 29.3 and 32.9 cm, respectively(p<0.01). 5) Depth of portal vein at the 12 and 11th intercostal space was 9.6, and 9.2 cm, respectively. 6) Diameter of portal vein at the 12 and lith intercostal space was 3.4 and 3.3 cm, respectively. 7) Dorsal margin of gallbladder at the 11 and 10th intercostal space was 43.1 and 45.5 cm, respectively(p<0.01). 8) Longitudinal diameter of gallbladder at the 11 and 10th intercostal space was 10.1 and 9.4 cm, respectively. 9) Transverse diameter of gallbladder at the 11 and 10th intercostal space was 4.0 and 3.7 cm, respectively. 4, Ultrasonogaphic measurments of dorsal margin, ventral margin, size and angles of the Korean native calves' liver. 1) Dorsal margin of liver at the 12, 11 and 10th intercostal space was 11.0, 9.6, and 12.4 cm, respectively(p<0.01). 2) Ventral margin of liver at the 12, 11 and 10th intercostal spate was 20, 24 and 26.1 cm, respectively(p<0.01). 3) Size of the liver at the 12, 11 and 10th intercostal space was 9.0, 14.6 and 13.8 cm, respectively(p<0.01). 4) Angle of liver at the 12, 11 and 10th intercostal space was 40, 46 and 37, respectively(p<0.01). 5. Ultrasonographic measurmants of dorsal margin, ventral margin, size and anglses of the korean native cattle's liver 1) Dorsal margin of the liver at the 12, 11 and 10th intercostal space was 14.4, 18.2 and 26, 3 cm, respectively. 2) Ventral margin of liver at the 12, 11 and 10th intercostal space was 41.1, 46.4 and 49.3 cm, respectively(p<0.01). 3) Size of the liver at the 12, 11 and 10th intercostal space was 26.8, 28.2 and 23.2 cm, respectively(p<0.01). 4) Angel of liverat the 15, 11 and 10 intercostal space was 41, 40.6 and 35.7, respectively(p<0.05). It was concluded that the ultrasonographic values oletermined in this study can be used as references for the diagnosis of morphologic changes in the hear and liver in korean native calves, and in the liver in korean native rattle.