• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.1029-1032
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• 2008

Nowadays, the necessity of the NDT technique for concrete structure has been increased due to maintenance of infra-structure. With this reason, NDT detecting technique has been considered as a effective maintenance method to prevent the rapid degradation of the infra-structure. In this study, to investigate the internal defect of concrete structure, ultrasonic detection device and radar equipment was applied then tested in laboratory and field. In the result of the experimental test, the internal cavity and steel arrangement can be detected and it was possible to adopt the ultrasonic detection method to the maintenance of concrete structure. And an algorithm for performing the maintenance procedure of concrete structure applying ultrasonic detection device and radar equipment was developed and suggested in this study.

• Agricultural and Biosystems Engineering
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• v.4 no.1
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• pp.1-7
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• 2003

Internal defects such as browning of the flesh and blackening and rot of the ovary of pear can be easily developed because of the inadequate environmental conditions during the storage and distribution of fruit. The quality assurance system for the agricultural product is to be settled in Korea. All defected agricultural products should be excluded prior to the distribution to enhance the commercial values. However, early stage on-line defect detection of agricultural product is very difficult and even more difficult in a case of the internal defects. The goal of this research is to develop a system that can detect and classify internal defects of agricultural produce on-line using VIS/NIR transmittance spectroscopy. And Shingo pear, which is one of the famous species of Korean pear, was used for the experiment. Soft independence modeling of class analogy (SIMCA) algorithm was employed to analyze the transmittance spectroscopic data qualitatively. On-line classification system was constructed and classification model was developed and validated. As a result, the correct classification rate (CCR) using the developed classification model was 96.1 ％.

• Smart Structures and Systems
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• v.17 no.1
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• pp.31-43
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• 2016

Applications of ultrasonic tomography to concrete structures have been reported for many years. However, practical and effective application of this tool for nondestructive assessment of internal concrete condition is hampered by time consuming transducer coupling that limits the amount of ultrasonic data that can be collected. This research aims to deploy recent developments in air-coupled ultrasonic measurements of solids, described in Part 1 of this paper set, to concrete in order to image internal inclusions. Ultrasonic signals are collected from concrete samples using a fully air-coupled (contactless) test configuration. These air coupled data are compared to those collected using partial semi-contact and full-contact test configurations. Two samples are considered: a 150 mm diameter cylinder with an internal circular void and a prism with $300mm{\times}300mm$ square cross-section that contains internal damaged regions and embedded reinforcement. The heterogeneous nature of concrete material structure complicates the application and interpretation of ultrasonic measurements and imaging. Volumetric inclusions within the concrete specimens are identified in the constructed velocity tomograms, but wave scattering at internal interfaces of the concrete disrupts the images. This disruption reduces defect detection accuracy as compared with tomograms built up of data collected from homogeneous solid samples (PVC) that are described in Part 1 of this paper set. Semi-contact measurements provide some improvement in accuracy through higher signal-to-noise ratio while still allowing for reasonably rapid data collection.

• Corrosion Science and Technology
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• v.20 no.4
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• pp.189-195
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• 2021

A technology for designing and licensing a dedicated radiation shielding facility needs to be developed for safe and efficient operation an R&D center. Technology development is important for smooth operation of such facilities. Causes of damage to internal structures (such as baffle former bolt (BFB) of pressurized water reactor) of a nuclear power reactor should be analyzed along with prevention and countermeasures for similar cases of other plants. It is important to develop technologies that can comprehensively analyze various characteristics of internal structures of long term operated reactors. In high-temperature, high-pressure operating environment of nuclear power plants, cases of BFB cracks caused by irradiated assisted stress corrosion cracks (IASCC) have been reported overseas. The integrity of a reactor's internal structure has emerged as an important issue. Identifying the cause of the defect is requested by the Korean regulatory agency. It is also important to secure a foundation for testing technology to demonstrate the operating environment for medium-level irradiated testing materials. The demonstration testing facility can be used for research on material utilization of the plant, which might have highest fluence on the internal structure of a reactor globally.

• Tuberculosis and Respiratory Diseases
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• v.62 no.3
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• pp.211-216
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• 2007

Hyperhomocysteinemia is an independent risk factor for cardiovascular, cerebrovascular and peripheral vascular diseases that are complicated by atherosclerosis and a thromboembolism. An increased level of plasma homocysteine develops from a genetic defect in the of enzyme for the homocysteine metabolism or a vitamin deficiency. Hyperhomocysteinemia has direct toxic effect on the vascular endothelium and causes damages to the antithrombotic action of vascular endothelial cells. Most cases of hyperhomocysteinemia are asymptomatic, but cardiopulmonary or cerebrovascular incidents developin rare cases. In the case of a thromboembolism with an unknown cause, hyperhomocysteinemia should be considered in a differential diagnosis. The authors report a case of pulmonary thromboembolism in a patient with hyperhomocysteinemia with a review of the relevant literature.

• The Korean Journal of Nuclear Medicine
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• v.24 no.2
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• pp.325-331
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• 1990

Radionuclide renal scintigraphies were performed in a 24-year-old man with right renal artery branch stenosis. Captopril enhanced $^{99m}Tc-DTPA$ renal scintigraphy revealed no abnormal finding in the right kidney. But, $^{99m}Tc-DMSA$ renal scintigraphy showed regional cortical photon deficient area corresponding to the area supplied by the stenotic branch artery. The defect size increased in captopril enhanced $^{99m}Tc-DMSA$ renal scintigrphy and nearly disappeared after successful transluminal renal angioplasty. This case suggests that the captopril enhanced $^{99m}Tc-DMSA$ renal scintigraphy may be a useful method in the evaluation of renovascular hypertension, especially due to branch renal srtery stenosis.

• The Journal of Internal Korean Medicine
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• v.40 no.5
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• pp.797-803
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• 2019

Introduction: The aim of this study was to report the effect of Korean medicine treatments on a stroke patient with homonymous hemianopsia. Case Presentation: A 50-year-old male with a posterior cerebral artery infarction had continuously deteriorating symptoms of right homonymous hemianopsia, fatigue, dizziness, and light sensitivity. Treatment with Korean medicine therapy, including acupuncture and herbal medicine significantly improved the patient's symptoms. The result of a visual field test (VFI) was also improved after treatment, and no side effects were observed during treatment. Conclusion: Korean medicine treatment can be considered an effective treatment for homonymous hemianopsia in stroke patients.

• Journal of Chest Surgery
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• v.13 no.4
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• pp.442-447
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• 1980

A 8-year-old boy underwent surgical correction of complete transposition S.D.D. of great arteries combined with subaortic ventricular septal defect and pulmonary stenosis [infundibular and valvular]. The operation consisted of an internal baffling connecting the left ventricle to the aorta through the ventricular septal defect. The pulmonary stenosis was corrected with the method of external connection, the right ventricle to the pulmonary artery using the conduit valve [20 mm] contained Hancock due to abnormal distribution of left coronary artery of which conduit due to abnormal distribution of left coronary artery of which the circumflex branch crossed the portion of right ventricular outflow tract. This case was suitable for corrective surgery-Rastelli operation-and the patient`s condition in very good until present [post-operative 5 months].

• Transactions of Materials Processing
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• v.3 no.1
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• pp.23-37
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• 1994

The upper bound element technique(UBET) is used to analyze the final stage of the axisymmetric forward extrusion. Kinematically admissible velocity field involving curved surface of velocity discontinuity is assumed. The required power to arise the piping defect is obtained and is compared with Aviture's solution a the same condition. Conditions for inception of the cavity and development of the pipe are predicted. The internal radius of the pipe and critical length of billet are also determined. Experiments are carried out for extrusion with lead specimens to investigate the piping phenomena. The theoretically predicted results showed reasonably good agreement with the experimental observation.

• Parasites, Hosts and Diseases
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• v.55 no.6
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• pp.659-660
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• 2017

Biliary ascariasis is still the leading cause of surgical complication of ascariasis, though its incidence has been dramatically reduced. Herein, we report a case of biliary ascariasis for the purpose of enhancing awareness of parasitic infections as a possible cause. A 72-year-old male visited the emergency room of Dankook University Hospital on 12 July 2015, complaining of right-upper-quadrant pain. By endoscopic retrograde cholangiopancreatography (ERCP), a tubular filling defect in the right hepatic duct was detected. The defect was endoscopically removed and diagnosed as an adult female of Ascaris lumbricoides worm, of 30 cm length. Upon removal of the worm, the pain subsided, and the patient was discharged without any complication. When treating cases of biliary colic, physicians should not neglect biliary ascariasis as the possible cause.