• Korean journal of dermatology
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• v.56 no.10
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• pp.631-635
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• 2018

Microvenular hemangioma (MVH) is a rare acquired benign vascular neoplasm, which presents commonly as a solitary purple-to-red nodule or plaque measuring approximately 10 mm in diameter. MVH occurs primarily on the extremities or the trunk. Most lesions are solitary, and multiple lesions are rare. Histopathological features of MVH include numerous, scattered, thin and irregularly branching small vessels in the dermis and endothelial cells without atypia. Owing to similarities in clinical morphology and histopathological features, MVH may often be indistinguishable from the early patch stage of Kaposi sarcoma. Immunohistochemical (IHC) analysis helps differentiate between the 2 diseases. The results of IHC tests in patients with MVH show positive staining for CD31 and smooth muscle actin and typically, negative staining for the human herpes virus 8 antigen. We report a rare case of multiple MVH clinically mimicking the early patch stage of Kaposi sarcoma in a 63-year-old woman who presented with a 3-year history of slowly growing, compressible, soft, bluish-purple macules and plaques on the trunk and right arm.

• Explosives and Blasting
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• v.38 no.4
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• pp.37-45
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• 2020

Todo was an uninhabited island located in the sea of Pusan Newport. It was a small island with the height of 32 m above sea level, and its area including the submerged part was approximately 24,400 ㎡. Unfortunately, the island was located exactly in the middle of the narrow entrance way to the North and South Container Wharfs of Pusan Newport so that a number of ships had to turn quickly to avoid collision with the island, which frequently caused collisions with other ships or cranes. To avoid such a danger and make the water way wider and deeper, the Ministry of Oceans and Fisheries decided to remove the island. This was believed to make even super-large vessels operate safely in the sea of Pusan Newport so that the competitiveness of the port could be highly enhanced. This paper describes in detail the whole process of the removing work, which was the first case of successful underwater blasting operation using bulk emulsion explosives and non-electric detonators to remove a whole island in South Korea.

• Journal of Medicine and Life Science
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• v.17 no.3
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• pp.65-73
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• 2020

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a single-gene disease of the cerebral small blood vessels caused by mutations in the NOTCH3 gene on chromosome 19. Although CADASIL was known as a rare disease, recent research has suggested that the NOTCH variants could be found frequently even in the general population. The main clinical features included recurrent stroke, migraine, psychiatric symptoms, and progressive cognitive decline. On brain magnetic resonance imaging, patients with CADASIL showed multifocal white matter hyperintensity lesions, lacunar infarcts, microbleeds, and brain atrophy. Among them, lacunar infarcts and brain atrophy are important in predicting the clinical outcomes of patients with CADASIL. In the Jeju National University Hospital, we have diagnosed 213 CADASIL patients from 2004 to 2020. Most NOTCH3 mutations were located in exon 11 (94.4%), and p.Arg544Cys was the most common mutation. The mean age at diagnosis was 61.0±12.8 years. The most common presenting symptoms were ischemic stroke (24.4%), followed by cognitive impairment(15.0%), headache (8.9%), and dizziness(8.0%). Although the exact prevalence of CADASIL in Jeju is still unknown, the disease prevalence could be as high as 1% of the population considering the prevalence reported in Taiwan. Therefore, it is necessary to discover efficient biomarkers and genetic tests that can accurately screen and diagnose patients suspected of having CADASIL in this region. Ultimately, it is urgent to explore the exact pathogenesis of the disease to identify leading substances of treatment potential, and for this, multi-disciplinary research through active support from the Jeju provincial government as well as the national government is essential.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.12
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• pp.1700-1709
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• 2019

Recently, many researches have been under way to develop systems (services) to support the safety navigation of ships, and in these studies, common difficulties have been encountered in assessing the usefulness and effectiveness of the developed system. To solve these problems, we propose the DEVS-based ship navigation modeling and simulation technique. Following the preceding study, we analyze the COLREG rules and reflected to officer and helmsman agent models for decision making. Also we propose estimation and interpolation techniques to adopt the motion characteristics of the actual vessel to simulation. In addition, we implement the navigation simulation system to reflect the designed proposed methods, and we present five-scenarios to verify the developed simulation system. And we conduct simulations according to each scenario and the results were reconstructed. The simulation results confirm that the components modelled in each scenario enable to operate according to the navigation relationships.

• Korean Journal of Remote Sensing
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• v.38 no.5_1
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• pp.559-570
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• 2022

When a satellite image has low spatial resolution, it is difficult to detect small objects. In this research, we aim to check the effect of super resolution on object detection. Super resolution is a software method that increases the resolution of an image. Unpaired super resolution network is used to improve Sentinel-2's spatial resolution from 10 m to 3.2 m. Faster-RCNN, RetinaNet, FCOS, and S²ANet were used to detect vessels in the Sentinel-2 images. We experimented the change in vessel detection performance when super resolution is applied. As a result, the Average Precision (AP) improved by at least 12.3% and up to 33.3% in the ship detection models trained with the super-resolution image. False positive and false negative cases also decreased. This implies that super resolution can be an important pre-processing step in object detection, and it is expected to greatly contribute to improving the accuracy of other image-based deep learning technologies along with object detection.

• Journal of Veterinary Clinics
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• v.39 no.4
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• pp.177-184
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• 2022

Caval syndrome is a severe complication of canine heartworm disease in which affected dogs present with various clinical signs that are often life-threatening. In cases of severe infection, adulticidal treatment has numerous complications as a result of a marked immune response against dead worms. Therefore, several surgical and non-surgical methods, including interventional extraction, have been applied in veterinary medicine. Despite the usefulness and efficiency of conventional retrieval devices, a few associated limitations must be addressed to reduce their risks and increase their applicability. Herein, we introduced a case of treating three dogs with caval syndrome by applying a newly developed heartworm basket device. The dogs were diagnosed with heartworm disease by heartworm antigen testing and direct smear. Imaging findings revealed remarkable remodeling of the right heart and pulmonary vessels and the presence of heartworms in the right heart. Additionally, heartworms were confirmed in the distal part of the abdominal aorta and femoral arteries in one dog, indicating aberrant systemic migration of the worms. Under general anesthesia, the heartworm basket device was introduced into the right heart via femoral venotomy and arteriotomy in one dog and jugular venotomy in the other two dogs. Although the number of cases in this study was small, the basket device was successful in gradual and cautious extraction of the heartworms in all three dogs. They exhibited good prognosis of clinical symptoms as indicated by imaging analyses.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2021.11a
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• pp.119-120
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• 2021

Radio equipment for maritime service and navigation aids installed on fishing vessels are required to comply with the performance standards KN60945_60533 that apply IEC 60945. The LTE-M transceiver was excluded from the target because it did not belong to the radio equipment of the ship station, and it acted as a cause of audible noise in the radio equipment for maritime service installed in the fishing vessel due to interference by radiated emission or conducted emission. In this paper, we analyze the impact of interference based on related cases and present institutional solutions for the diversification of LTE-M.

• International Journal of Stem Cells
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• v.16 no.2
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• pp.145-155
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• 2023

Background and Objectives: Embryologically, mesodermal development is closely related to the development of various organs such as muscles, blood vessels, and hearts, which are the main organs that make up the body. However, treatment for mesoderm developmental disorders caused by congenital or acquired factors has so far relied on surgery and drug treatment for symptom relief, and more fundamentally, treatment for mesoderm developmental disorders is needed. Methods and Results: In our study, microRNA (miRNA), which plays an important role in the mesoderm development process, was identified and the developmental function was evaluated. miRNAs consist of small nucleotides, which act as transcription factors that bind to the 3' untranslated region and suppressed target gene expression. We constructed the human embryonic stem cell (hESC) knockout cell line and analyzed the function and characteristics of miR-5739, which plays an important role in mesoderm lineage. miR-5739 acts as a transcription factor targeting SMA, Brachyury T, Hand1, which controls muscle proliferation and differentiation, and KDR gene, which regulates vessel formation in vitro. In vivo results suggest a role in regulating muscle proliferation and differentiation. Gene ontology analysis confirmed that the miR-5739 is closely related to genes that regulate muscle and vessel proliferation and differentiation. Importantly, abnormal expression of miR-5739 was detected in somatic cells derived from patients with congenital muscle disease. Conclusions: Our study demonstrate that miR-5739 gene function significantly affects transcriptional circuits that regulate muscle and vascular differentiation during embryonic development.

• Korean Journal of Radiology
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• v.21 no.6
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• pp.756-763
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• 2020

Objective: To evaluate the effects of attenuation threshold on CT pulmonary vascular volume ratios in children and young adults with congenital heart disease, and to suggest an optimal attenuation threshold. Materials and Methods: CT percentages of right pulmonary vascular volume were compared and correlated with percentages calculated from nuclear medicine right lung perfusion in 52 patients with congenital heart disease. The selected patients had undergone electrocardiography-synchronized cardiothoracic CT and lung perfusion scintigraphy within a 1-year interval, but not interim surgical or transcatheter intervention. The percentages of CT right pulmonary vascular volumes were calculated with fixed (80-600 Hounsfield units [HU]) and adaptive thresholds (average pulmonary artery enhancement [PA_avg] divided by 2.50, 2.00, 1.75, 1.63, 1.50, and 1.25). The optimal threshold exhibited the smallest mean difference, the lowest p-value in statistically significant paired comparisons, and the highest Pearson correlation coefficient. Results: The PA_avg value was 529.5 ± 164.8 HU (range, 250.1-956.6 HU). Results showed that fixed thresholds in the range of 320-400 HU, and adaptive thresholds of PA_avg/1.75-1.50 were optimal for quantifying CT pulmonary vascular volume ratios. The optimal thresholds demonstrated a small mean difference of ≤ 5%, no significant difference (> 0.2 for fixed thresholds, and > 0.5 for adaptive thresholds), and a high correlation coefficient (0.93 for fixed thresholds, and 0.91 for adaptive thresholds). Conclusion: The optimal fixed and adaptive thresholds for quantifying CT pulmonary vascular volume ratios appeared equally useful. However, when considering a wide range of PAavg, application of optimal adaptive thresholds may be more suitable than fixed thresholds in actual clinical practice.

• Journal of the Society of Naval Architects of Korea
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• v.61 no.3
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• pp.170-184
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• 2024

With the advancement of autonomous navigation technology in maritime domain, there is an active research on swarming Unmanned Surface Vehicles (USVs) that can fulfill missions with low cost and high efficiency. In this study, we propose a formation control algorithm that maintains a certain shape when multiple unmanned surface vehicles operate in a swarm. In the case of swarming, individual USVs need to be able to accurately follow the target state and avoid collisions with obstacles or other vessels in the swarm. In order to generate guidance commands for swarm formation control, the potential field method has been a major focus of swarm control research, but the method using the potential field only uses the position information of obstacles or other ships, so it cannot effectively respond to moving targets and obstacles. In situations such as the formation change of a swarm of ships, the formation control is performed in a dense environment, so the position and velocity information of the target and nearby obstacles must be considered to effectively change the formation. In order to overcome these limitations, this paper applies a method that considers relative velocity to the potential field-based guidance law to improve target following and collision avoidance performance. Considering the relative velocity of the moving target, the potential field for nearby obstacles is newly defined by utilizing the concept of Velocity Obstacle (VO), and the effectiveness and efficiency of the proposed method is verified through swarm control simulation, and swarm control experiments using a small scaled unmanned surface vehicle platform.