• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.363-364
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• 2002

We describe quadrature type surface coil for functional magnetic resonance imaging at 3T MRI system. The coil consisted of two coplanar resonators and was used as both transmitter and receiver. The signal-to-noise ratio (SNR) of the coil was compared with that of a standard birdcage head coil. Visual cortex activation on normal subjects using LED flicker was performed. The SNR of surface coil was found to be better than that of the conventional head coil.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.2
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• pp.251-256
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• 2011

The radial overcut in micro electrochemical machining was investigated. The prediction of overcut is important not only for the machining accuracy but also for the shape control of micro structures. In micro ECM, machining gap or overcut depends on electrolyte, pulse voltage, pulse duration and dissolution time etc. Understanding of electrochemical dissolution rate is necessary for the overcut prediction. In this paper, the radial overcut of micro electrochemical machining according to pulse duration and dissolution time was simulated using electrochemical principles and also experimentally estimated.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.351-357
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• 2007

The transition zone between railway embankment and structures, or different track types is known to be an area in which problems often arise and where extra care needs to be taken with maintenance. Differences in track stiffness have dynamic effects and these increase the force in the track and the extent of deformation. In this study, the criteria for the change ratio of track stiffness along transition area, and proper transition length are presented through train/track interaction analyses. Those are derived on the basis of permissible limitations of train and track performances such as rail stress, uplift force of fastener, reduction of dynamic wheel force, and acceleration of car body. A feasible method of evaluation of track stiffness which is necessary when a designer reviews whether the criteria are satisfied or not is also presented.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.3
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• pp.80-87
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• 2002

Tungsten carbide microshaft is used as micro-punch, electrode of MEDM (micro-electro-discharge machining), and micro-tool because it has high hardness and high rigidity. In this study, the tungsten carbide microshaft was fabricated using electrochemical machining. Concentration of material removal at the sharp edge and metal corrosion layer affect the shape of the microshaft. Control of microshaft shape was possib1e through conditioning the machining voltage and electrolyte concentration. By applying periodic voltage, material removal rate increased and surface roughness improved. The fabricated microshaft in $H_2 SO_4$ electrolyte maintained sharper end edge and better surface finish than those fabricated by other electrolytes.

• Korean Journal of Veterinary Service
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• v.30 no.1
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• pp.85-93
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• 2007

The purpose of this study was to investigate the infection situation of several diseases (post-weaning atrophic pigs) such as porcine reproductive and respiratory syndrome (PRRS) in swine breeding complex in Jeonbuk-Iksan. From February to October in 2006, a total of 28 swine samples (6-10 week old) were collected from 6 farms and examined by polymerase chain reaction(PCR) and clinical signs. In the rate of single infection, pneumonia was top (32.1%), followed by salmonellosis (14.2%)and Glasser's disease (10.7%) and double infection pneumonia/Glasser's disease (17.8%) was detected. PCR was detected of PCV 2 from 28 (100.0%) and PPV 6 (21.4%), PRRS PORF6 10 (35.7%) and POR7 11 (39.2%), but HC and AD was not detected. The results suggest that PCV 2 is complex infection PRRS, PPV and bacterial disease.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.24 no.1
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• pp.23-33
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• 2017

Purpose: The purpose of this phenomenological study was to explore middle-aged child care providers' experience in caring for children in the community. Methods: The participants were 10 middle-aged child care providers. In-depth interviews were conducted between August and September, 2014 until data. Colaizzi's method of data analysis was applied to inductively determine themes and formulated meanings. Data saturation was achieved and methodological rigor was established Results: Four themes were extracted from 12 meanings. The four themes of the child care providers' experience in caring for children were: 1) weariness from care-giving, 2) the search for one's own solutions, 3) a cheerful attitude to life, 4) the opportunity to start a new life. Conclusion: The results of this study provide useful information for understanding child care providers' experiences in caring for children and establishing effective strategies to support these child care providers.

• Proceedings of the Korean Society of Medical Physics Conference
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• 1999.11a
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• pp.427-428
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• 1999

• Proceedings of the Korean Society of Medical Physics Conference
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• 1999.11a
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• pp.429-430
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• 1999

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.4
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• pp.436-443
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• 1991

A case of melanotic neuroectodermal tumor of infancy(MNTI) in 5 month old girl is presented with review of the literature. The review of literature indicated that there have been 189 reported cases of this lesion and there were 9 cases of malignant tumor for a rate of 4.8%. This rate of malignancy is very high in view of the fact that the tumor has been described as benign. And immunohistochemical study using avidin-biotin conjugate method demonstrated that this tumor had been originated from neural crest.

• Journal of Korean Neurosurgical Society
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• v.48 no.5
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• pp.461-464
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• 2010

The authors report a 58-year-old woman with low-grade fibromyxoid sarcoma primarily located in the right paravertebral area with extension to L4 neural foramen. The patient complained lower back pain with radiating pain along the posterolateral aspect of the right lower leg. She underwent subtotal surgical removal and Cyber Knife therapy. Diagnosis was made by strikingly characteristic microscopic appearance of a bland spindle cell sarcoma which contained numerous giant collagen rosettes and was also supported by immunohistological findings. The diagnostic image findings and literatures are reviewed and discussed.