• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.2
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• pp.61-76
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• 2021

As the number of existing road tunnels increases every year, collapse and floor heaving accidents occur frequently during construction. The collapse among tunnel accidents dominates, so that studies related to the floor heaving are relatively insufficient. Accordingly, many studies to reinforce the lower part of the tunnel have been conducted, but the analysis on the effect of the curvature of the tunnel floor is insufficient. Therefore, in this study, the effects of the upper analysis area height and the coefficient of lateral earth pressure of the tunnel located on a tuff deterioration zone with a large rock cover, as well as the floor curvature, were examined through sensitivity analysis. As a result of the analysis, it turned out that the overall stability of the tunnel increases as the floor curvature increases, the coefficient of lateral earth pressure decreases, and the upper analysis region increases.

• Imaging Science in Dentistry
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• v.50 no.4
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• pp.291-298
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• 2020

Purpose: The detection and exact localization of penetrating foreign bodies are crucial for the appropriate management of patients with dentoalveolar trauma. This study compared the efficacy of cone-beam computed tomography (CBCT) and spiral computed tomography (CT) scans for the detection of different foreign bodies composed of 5 frequently encountered materials in 2 sizes. The effect of the location of the foreign bodies on their visibility was also analyzed. Materials and Methods: In this in vitro study, metal, tooth, stone, glass, and plastic particles measuring 1×1×1 mm and 2×2×2 mm were prepared. They were implanted in a sheep's head in the tongue muscle, nasal cavity, and at the interface of the mandibular cortex and soft tissue. CBCT and spiral CT scans were taken and the visibility of foreign bodies was scored by 4 skilled maxillofacial radiologists who were blinded to the location and number of foreign bodies. Results: CT and CBCT were equally accurate in visualizing metal, stone, and tooth particles of both sizes. However, CBCT was better for detecting glass particles in the periosteum. Although both imaging modalities visualized plastic particles poorly, CT was slightly better for detecting plastic particles, especially the smaller ones. Conclusion: Considering the lower patient radiation dose and cost, CBCT can be used with almost equal accuracy as CT for detecting foreign bodies of different compositions and sizes in multiple maxillofacial regions. However, CT performed better for detecting plastic particles.

• Imaging Science in Dentistry
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• v.51 no.2
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• pp.149-154
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• 2021

Purpose: This study aimed to investigate the computed tomography and magnetic resonance imaging features of giant cell tumors in the temporomandibular joint region to facilitate accurate diagnoses. Materials and Methods: From October 2007 to June 2020, 6 patients (2 men and 4 women) at Yonsei University Dental Hospital had histopathologically proven giant cell tumors in the temporomandibular joint. Their computed tomography and magnetic resonance imaging findings were reviewed retrospectively, and the cases were classified into 3 types based on the tumor center and growth pattern observed on the radiologic findings. Results: The age of the 6 patients ranged from 25 to 53 years. Trismus was found in 5 of the 6 cases. One case recurred. The mean size of the tumors, defined based on their greatest diameter, was 32 mm (range, 15-41 mm). The characteristic features of all cases were a heterogeneously-enhancing tumorous mass with a lobulated margin on computed tomographic images and internal multiplicity of signal intensity on T2-weighted magnetic resonance images. According to the site of origin, 3 tumors were bone-centered, 2 were soft tissue-centered, and 1 was peri-articular. Conclusion: Computed tomography and magnetic resonance imaging yielded a tripartite classification of giant cell tumors of the temporomandibular joint according to their location on imaging. This study could help clinicians in the differential diagnosis of giant cell tumors and assist in proper treatment planning for tumorous diseases of the temporomandibular joint.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.6
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• pp.389-402
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• 2022

The purpose of the study is to analyze the significant impacts of expectations, performance, complaints, and fairness that affect consumer satisfaction. The methodology involves reviewing and referencing relevant literature carefully, then proposing a model for customer satisfaction. This study is empirically based on a survey with 50 respondents who work in the field of import and export in the region stretching from the north to the south of Vietnam. The sampling method used in this study is the in-depth interview method. The results show that: (1) expectation has a specific impact on customer satisfaction, (2) performance has a positive impact on customer satisfaction, and (3) complaint which is an intermediary factor between expectation, performance, and fairness has an impact on satisfaction, (4) fairness has a positive effect on satisfaction, in addition, fairness is an extremely important feature when customers choose an import-export service. Research implies that increasing expectations, performance, and fairness results in an improved customer experience and satisfaction when they use the service. It is suggested that the complaint factor continue to be studied and looked into because it still has some effect on satisfaction and is an intermediate variable that changes how the other factors relate to each other.

• Journal of Digital Convergence
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• v.19 no.11
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• pp.45-52
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• 2021

This study conducted t-test and ANOVA analysis, influence of importance-satisfaction, regression analysis to local food and restaurants to the purchase intention in Busan. The subjects of this study were tourists who visited local restaurants in Busan, and the final 392 copies were used for empirical analysis. As a result of the study, first, there will be a significant difference in the recognition of local foods in Busan according to the visitor's region. In all samples, the recognition was high in the order of pork stock, wheat noodle, sauteed·fired soft eel, grilled·ell sashmi. On the other hand, sansung bulgogi, Dongrae pajeon, and sansung makkŏlli were the lowest. Second, in the difference between importance and satisfaction of local restaurants in Busan, 'there is a different taste compared to other regions' showed high satisfaction and importance. Third, In the relationship between the awareness of local restaurants in Busan and the purchase intention, it was found to be effective in service, facilities, prices and locality and cleanliness were rejected.

• Journal of Veterinary Clinics
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• v.39 no.5
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• pp.258-263
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• 2022

An eight-year-old, intact female, Shih-Tzu, weighing 4.5 kg presented with complaints of anorexia, pale mucous membrane, and vomiting for the past 5 days. On physical examination, nausea, abdominal pain, and melena were noted. On hematologic examination, severe anemia and thrombocytosis were identified. On radiographs examination, soft tissue opacity with small faint mineral opacity mass in the mid-abdomen and two mineral opacity regions in the cranial aspect of mass were identified. Ultrasonographic findings showed thickening of descending duodenal wall with loss of layering and mineralization within the duodenal wall and mesentery adjacent to the duodenal lesion. Computerized tomography showed circumferential wall thickening of descending duodenum with mineralization. Mineralization of the mesentery and mesenteric lymph nodes was identified. Based on the diagnostic imaging, the tentative diagnosis was descending duodenal tumor with dystrophic mineralization. Endoscopy revealed mucosal hemorrhage and erythema within the descending duodenum and stomach. Surgery was performed, and mineralization in the pancreatic tail to duodenum and mesentery was found. Resection of the duodenum, regional lymph node, and mineralized pancreatic region and the duodenal anastomosis were performed. The histologic examination revealed a high-grade undifferentiated duodenal carcinoma with metastases to the regional lymph node and mesentery. The patient was managed with supportive therapy for 8 days and discharged. The patient was followed up for 5 months and there were no complications.

• Archives of Plastic Surgery
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• v.49 no.3
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• pp.444-447
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• 2022

Reconstruction of soft tissue defects around the knee is challenging, and the most common solution is to use various locoregional flaps or, in some difficult cases, a free flap. The distally based anterolateral thigh (dALT) flap is a commonly used flap that relies on reverse blood flow from the descending branch of the lateral circumflex femoral artery (d-LCFA). Here, we present the case of an anteromedial knee reconstruction using a dALT flap after resection of a pleomorphic undifferentiated sarcoma. The tumor resection resulted in a 14 × 7 cm defect, and a dALT flap, measuring 20 × 8 cm was elevated. During the surgery, we found a robust oblique branch of the LCFA (o-LCFA) sending off two sizable perforators to the anterolateral thigh region, whereas the d-LCFA was relatively small with no usable perforators. Therefore, we harvested a dALT flap relying on reverse flow from the o-LCFA. The patient's postoperative course was uneventful, and the flap survived without complications. This report demonstrates that reverse flow from the o-LCFA may be an alternative to nourish a dALT flap in cases where the d-LCFA is hypoplastic or suitable perforators from the d-LCFA are unavailable.

• The Korean Journal of Pain
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• v.36 no.4
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• pp.458-464
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• 2023

Background: Fibromyalgia (FM) is a complex disorder characterized by widespread chronic pain and tenderness in the muscles, ligaments, and soft tissues. It is a chronic pain condition often accompanied by other symptoms and comorbidities. To effectively manage FM, it is crucial to obtain fundamental epidemiological data pertaining to the target population. Therefore, this study was conducted to elucidate the epidemiological characteristics of FM in the Korean population. Methods: Population-based medical data of 51,276,314 subscribers to the National Health Insurance Service of Korea from 2014 to 2018 were used in this study. Results: The overall incidence of FM ranged from 441 (2014) to 541 (2018) cases per 100,000 person-years, with a higher prevalence observed among female patients compared to male patients. The incidence gradually increased until middle age, followed by a decrease. The highest incidence rates were observed in the fifth decade of life for females and the sixth decade of life for males. When categorizing the affected parts of the body, the shoulder region was observed to be the most frequently affected. A comparison of the drug prescriptions based on medical specialty showed that antidepressants were the most commonly prescribed medications. The management of FM leads to consistent increases in medical expenses, regional disparities, and variations in prescription patterns across different medical specialties. Conclusions: The findings of this study will not only contribute to the understanding of FM characteristics but also provide a vital foundation for efficient management of FM in Korea.

• Journal of Veterinary Clinics
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• v.40 no.4
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• pp.283-287
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• 2023

A 10-year-old spayed female beagle dog presented with a 2-month history of third-eyelid elevation in the left eye (OS). Ophthalmic examination revealed slightly diminished corneal and palpebral reflexes along with exophthalmos in the OS. Schirmer's tear test and intraocular pressure values were within the normal range for the OS. Slit-lamp biomicroscopy revealed protrusion of the third eyelid and corneal opacity in the OS. Fundoscopy revealed a prominent black mass in the OS covering the optic nerve. Tapetal hyper-reflectivity was also observed around the mass. Ocular ultrasonography showed a 0.74 × 0.67 cm echogenic posterior segment mass around the optic nerve protruding into the retrobulbar space. Computed tomography revealed a contrast-enhanced soft tissue lesion in the posteromedial aspect of the left eyeball protruding into the retrobulbar region, and the optic nerve was suspected to be involved. No evidence of osteolytic changes in the adjacent bone or distant metastasis was observed. Enucleation was performed to prevent potential metastasis or local invasion of the mass and to relieve discomfort due to exposure to keratopathy resulting from lagophthalmos. Histopathological examination revealed a central choroidal melanocytoma extending into the optic nerve. No local recurrence was detected until 16 months postoperatively.

• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.17-17
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• 1998

Synchrotron radiation is produced when charged particles moving with relativistic velocities a are accelerated - for example, deflected by the bending magnets which guide the electron or p positrons in circular accelerators or storage rings. By using special focusing magnetic lattices i in the particle accelerators it is possible to make the dimensions of the particle beam very small with a hi맹 charge density which results in a light source with high b디lIiance. Synchrotron light h has important properties which make it ideal for a wide range of investigations in surface s science. The fact that the spectrum of electromagnetic radiation emitted in a bending magnet e extends in a continuum from the 얹r infra red region to hard x-rays means that it is id않I for a v variety of spectroscopic studies. Since there are no convenient lasers, or other really bright l light sources, in the vacuum ultraviolet and soft x-ray re.밍ons the development of synchrotron r radiation has enabled enormous advances to be made in this di펌C비t spectr따 re밍on. P Polarization-dependent measurements, for ex없nple ellipsometry or circular dichroism studies a are possible because the radiation has a well-defined polarization - linear in the plane of orbit w with additional right-circular, or left-circular, components for emission an생es above, or below, t the horizontal, respectively. Since the synchrotron light is emitted from a bunch of charge c circulating in a ring the light is emitted with a well-defined time structure with a short flash of l light every time a bunch passes an exit port. The time structure depends on the size of the ring a and the number and sequence of filling of the bunches. A pulsed light source enables time¬r resolved studies to be performed which provide direct information on the lifetimes and decay m modes of excited states and in addition opens up the possibility of using time of flight t techniques for spectroscopic studies. The fact that synchrotron radiation is produced in a clean u ultrahi야 vacuum environment is of gr않t importance for surce science studies. The current t비rd generation synchrotron light sources provide exceptionally high baliance and stability a and open up possibilities for experiments which would have been inconceivable only a short time ago.