• Restorative Dentistry and Endodontics
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• v.47 no.4
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• pp.37.1-37.9
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• 2022

Objectives: This study aimed to evaluate the prevalence of apical periodontitis (AP) in the mesiobuccal roots of root canal-treated maxillary molars. Materials and Methods: One thousand cone-beam computed tomography images of the teeth were examined by 2 dental specialists in oral radiology and endodontics. The internal anatomy of the roots, Vertucci's classification, quality of root canal treatment, and presence of missed canals were evaluated; additionally, the correlation between these variables and AP was ascertained. Results: A total of 1,000 roots (692 first molars and 308 second molars) encompassing 1,549 canals were assessed, and the quality of the root canal filling in the majority (56.9%) of the canals was satisfactory. AP was observed in 54.4% of the teeth. A mesiolingual canal in the mesiobuccal root (MB2 canal) was observed in 54.9% of the images, and the majority (83.5%) of these canals were not filled. Significant associations were observed between the presence of an MB2 canal and the quality of the root canal filling and the presence of AP. Conclusions: AP was detected in more than half of the images. The MB2 canals were frequently missed or poorly filled.

• Journal of the Korean Institute of Gas
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• v.17 no.6
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• pp.1-7
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• 2013

Internal pressure variation analysis and actual holding time test on ISO LNG tank containers which were made in Korea for the first time according to the special notification of ISO tank container manufacture have been conducted during the transport demonstration projects of the tank containers by tractor, train and ship. The internal pressure of the LNG tank container increased rapidly after LNG filling and dropped during moving the container. However, it was stabilized as time passed and followed the liquid-vapor equilibrium graph. In addition, actual holding time of the tank container was more than 20 days which was satisfied with the special notification of LNG tank container manufacture.

• Journal of Korean Neurosurgical Society
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• v.45 no.4
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• pp.260-263
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• 2009

Internal carotid artery (ICA) trapping can be used for treating intracranial giant aneurysm, blood blister-like aneurysms and ICA rupture during the surgery. We present a novel ICA trapping technique which can be used with insufficient collaterals flow via anterior communicating artery (AcoA) and posterior communicating artery (PcoA). A patient was admitted with severe headache and the cerebral angiography demonstrated a typical blood blister-like aneurysm at the contralateral side of PcoA. For trapping the aneurysm, the first clip was placed at the ICA just proximal to the aneurysm whereas the distal clip was placed obliquely proximal to the origin of the PcoA to preserve blood flow from the PcoA to the distal ICA. The patient was completely recovered with good collaterals filling to the right ICA territories via AcoA and PcoA. This technique may be an effective treatment option for trapping the aneurysm, especially when the PcoA preservation is mandatory.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.11
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• pp.78-81
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• 1995

In imaging the samples or human internal organs in a tube shape, general RF-probe types (that encircles a sample or places on top of the sample) are usually unsuitable for the internal imaging due to the degradation of signal-to-noise ratios(SNR's). In the present study the inside-out probes for Magnetic Resonance Imaging (MRI) have been constructed in the three different shapes such as an anti-solenoidal, a saddle and a dual surface types which are positioned as close to the area as possible by putting the probe inside the tubelike sample to improve filling factor. RF-field distributions have also been calculated depending upon the geometrical changes of anti-solenoid probes. Moreover, the performance of the inside-out probes has been checked by measuring SNR's of the images acquired. The inside-out probes constructed in this study produced better SNR's and rf-field uniformity in the area close to the probes in comparing with any other commercial probes. There is a high possibility that the constructed probes in the present study are applicable to the diagnosis of human bodies.

• Tuberculosis and Respiratory Diseases
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• v.52 no.3
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• pp.288-293
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• 2002

A 32-year-old woman presented with cough and hemoptysis. The radiologic findings showed increased interstitial markings in the right lung, a slightly decreased lung volume in the RLL and a hypoplastic right pulmonary artery with collaterals in the mediastinum and subpleural area. The pulmonary angiography showed an abrupt occlusion of the right lower pulmonary artery. The echocardiographic findings indicated pulmonary hypertension. A doppler leg ultrasonograph disclosed that the left popliteal vein was occluded with collateral veins, not filling the defect in the venous lumen. The D-dimer increased 1.0 ug/ml. This condition was initially misdiagnosed as a congenital pulmonary artery agenesis. Finally, a chronic pulmonary thromboembolism with a deep vein thrombosis was confirmed.

• Tunnel and Underground Space
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• v.5 no.2
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• pp.104-113
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• 1995

Shear strength of the discontinuity on which the pre-failure of rock slope was occurred during surface excavation was measured through the direct shear test using core samples obtained in-situ. Internal friction angle was increased as the roughness of discontinuity surface(JRC) was increased. Results of the tilt test using core samples of higher JRC also showed very similar trend as those of the direct shear test. When the samples replicated from natural cores were used int he tilt test, results of friction angles showed almost perfect continuation of the residual friction angles from the direct shear test. However, when the gouge material existed in the discontinuity the internal friction angle strongly depended upon the rate of filling thickness to the height of asperity irrespective of the JRC. Based on the results of both direct shear test and tilt test internal friction angle and cohesion of discontinuity, which reflect the in-situ conditions fo pre-sliding failure and also can be used for the optimum design of support system, were assessed. Two kinds of support measures which were expected to increase the stability of rock slope were considered; lowering of slope face angle and installation of rock cable. But, it was found that the first method might lead to more unstable conditions of rock slope when the cohesion of discontinuity plane was negligibly low and in that case the support systems of any kind which could exert actual resisting force were needed to ensure the permanent stability of rock slope.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.4
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• pp.179-185
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• 2012

When manufacturing die casting mold, generally, the casting layout design should be considered based on the relation among injection system, casting condition, gate system, and cooling system. Also, the extent or the location of product defects was differentiated according to the various relations of the above conditions. In this research, in order to optimize casting design of an automobile part (Gear Box) Computer Aided Engineering (CAE) was performed by using the simulation software (Z Cast). The simulation results were analyzed and compared with experimental results. During the mold filling, internal porosities caused by air entrap were predicted and reduced remarkably by the modification of the gate system and the configuration of overflow. With the solidification analysis, internal porosities caused by the solidification shrinkage were predicted and reduced by the modification of the gate system. For making a better production die casting tool, cooling systems on several thick areas are proposed in order to reduce internal porosities caused by the solidification shrinkage.

• Tuberculosis and Respiratory Diseases
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• v.72 no.2
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• pp.218-222
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• 2012

Pulmonary artery intimal sarcoma is a rare tumor with no characteristic symptoms. It is frequently misdiagnosed as pulmonary embolism. We report a case of pulmonary artery intimal sarcoma in a 48-year-old man with dyspnea, cough and blood-tinged sputum. He was initially suspected and treated as a pulmonary embolism. Computed tomography of the chest showed filling defects occupying the entire luminal diameter of the right and left pulmonary artery as well as extraluminal extension of the intraluminal mass. Surgical resection of the tumor confirmed pulmonary artery intimal sarcoma. After surgery, he received 8 cycles of combined chemotherapy consisting of doxorubicin and ifosfamide. After 8 cycles, Computed tomography of the chest showed interval regression of the residual tumor. Radiotherapy was done as total 6,000 cGy for 5 weeks, following the 8th chemotherapy. The patient's condition was successfully stabilized with chemotherapy and radiotherapy.

• The Journal of KAIRB
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• v.6 no.2
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• pp.48-55
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• 2024

Purpose: The purpose of this study is to introduce the Institutional Review Board (IRB) member-based internal audit method performed at A University Hospital, a secondary medical institution, and to identify the differences in audit results according to the characteristics of each auditor and the factors affecting the internal audit results. Furthermore, we will find out what needs to be improved in the internal audits to achieve Quality assurance (QA) objectives for human subject research conducted in medical institutions. Methods: The auditors were divided into group A (IRB member belonging to institution A) and group B (clinical trial QA administrator belonging to other institutions) and independently inspected the 2 studies using the same internal audit checklist (consisting of 11 domains, 130 items), and the differences in the internal inspection checklists written by each auditor were compared and analyzed. Results: In the case of audit for the study 1, the number of missing checklists is 1 for group A and 0 for group B, and the number of the matters to be pointed out is 1 for group A and 12 for group B. In the case of audit for the study 2, the number of missing checklists is 2 for both A and B, and the number of points is 5 for A and 4 for B. The differences in the internal audit results written by each auditor that the authors verified are summarized as follows. First, there were more comments from group B auditor than from group A auditor. Second, the results may vary because each auditor has different criteria for evaluating the appropriateness of an item. Third, there are cases where the questions on the checklist are vague or the definition is not clear, so they have the same opinion but check it with different answers. Fourth, if the auditors make a mistake when filling out the checklist, it causes to led to different the results. Conclusion: We propose the following items that should be improved in order to conduct consistent and efficient internal audits. First, it is necessary to test the tool in order to carry out reliable and consistent internal audits. Second, it is necessary to complete specialized training related to internal audit before conducting internal audit. Third, before notifying the audit results, it is necessary to have a procedure or a final review system to check whether the audit contents are appropriate. Fourth, Institutional support is needed to recruit specialized personnel for internal audits.

• Structural Engineering and Mechanics
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• v.59 no.3
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• pp.559-577
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• 2016

There are many theoretical analyses and experimental studies of the hydrodynamics for the tension leg platform (TLP) of a floating wind turbine. However, there has been little research on the arrangement of the TLP's internal structure. In this study, a TLP model and a 5-MW wind turbine model as proposed by the Minstitute of Technology and the National Renewable Energy Laboratory have been adopted, respectively, to comprehensively analyze wind effects and wave and current combinations. The external additional coupling loads on the TLP and the effects of the loads on variables of the internal structure have been calculated. The study investigates preliminary layout parameters-namely, the thickness of the tension leg body, the contact mode of the top tower on the tension leg, the internal stiffening arrangement, and the formation of the spoke structure-and conducts sensitivity analyses of the TLP internal structure. Stress is found to be at a maximum at the top of the tension leg structure and the maximum stress has low sensitivity to the load application point. Different methods of reducing maximum stress have been researched and analyzed, and the effectiveness of these methods is analyzed. Filling of the spoke structure with concrete is discussed. Since the TLP structure for offshore wind power is still under early exploration, arrangements and the configuration of the internal structure, exploration and improvements are ongoing. With regard to its research and analysis process, this paper aims to guide future applications of tension leg structures for floating wind turbine.