• Journal of Advanced Marine Engineering and Technology
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• v.23 no.2
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• pp.159-167
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• 1999

This paper presents a new transient voltage blocking device(TOBD)which low power and high frequency bandwidth to protect info-communication facilities from transient voltages. Conventional protection devices have some problems such as low frequency bandwidth low ener-gy capacity and high remnant voltage. in order to improve these limitations a hybrid type TOBD which consists of a gas tube avalanche diodes and junction type field effect transistor (JFETs) is developed. The TOBD differs from the conventional protection devices in configuration and JFETs are used as an active non-linear element and a high speed switching diode with low capacitance limited high current. Therefore the avalanche diode with low energy capacity are protected from the high current and the TOBD has a very small input capacitance. From the performance test using combination surge generator which can produce $1.2/50{\mu}m$ 4.2 kV/max, $8/20{\mu}m$ 2.1 kAmax it is confirmed that the proposed TOBD has an excellent protection per-formance in tight clamping voltage and limiting current characteristics.

• Journal of the Korean Ceramic Society
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• v.54 no.3
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• pp.235-242
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• 2017

Changes in polarization and thermal expansion coefficients during temperature increase of a poled lead zirconate titanate (PZT) cube specimen switched by an electric field at room temperature are measured. The measured data are analyzed to construct governing differential equations for polarization and strain changes. By solving the differential equations, an experimental formula for the high temperature behavior of ferroelectric materials is obtained. It is found that the predictions by the formula are in good agreement with measures. From the viewpoint of macroscopic remnant state variables, it appears that the processes of electric field-induced switching at different temperatures are identical and independent of temperature between $20^{\circ}C$ and $110^{\circ}C$.

• Korean Journal of Veterinary Research
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• v.59 no.2
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• pp.105-108
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• 2019

A 4-year-old cat was referred for a suspected pulmonary mass. True diaphragmatic hernia presence was diagnosed via computed tomography (CT). There was a thin membrane covering the diaphragmatic defect. The membrane was thinner than the diaphragm. After contrast injection, the membrane was less enhanced than that of the normal diaphragm. The membrane was identified as a remnant of the parietal pleura. In addition, contrast-enhanced CT images provided clarity in viewing the herniated liver and falciform fat. A thinner membrane, covering the diaphragmatic defect, and attached to the thicker normal diaphragm, is considered a unique CT feature of true diaphragmatic hernia.

• Archives of Craniofacial Surgery
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• v.23 no.5
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• pp.241-245
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• 2022

Cervical chondrocutaneous branchial remnants are very rare congenital lesions of the lateral neck; thus, our knowledge of this condition derives almost entirely from occasional case reports in the literature. They are thought to originate from the branchial arches and, therefore, can be found anywhere on the pathway along which those branchial arches migrate during embryogenesis. We report the case of a 5-year-old girl presenting with a cervical chondrocutaneous branchial remnant on the right lateral neck that had existed since birth, with no other anomalies.

• Journal of Trauma and Injury
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• v.35 no.1
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• pp.43-45
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• 2022

Epidural hematoma (EDH) can sometimes be life-threatening, although small-volume EDHs can resolve spontaneously like other intracranial hematomas. However, in rare cases, EDH can transform into a chronic form instead of disappearing. In contrast to subdural hematoma, there is no agreed-upon definition or treatment of chronic EDH. A 41-year-old male patient with acute EDH in the bilateral paravertical area due to partial rupture of the sagittal sinus was operated first, and then remnant contralateral hematoma was treated conservatively. One month after surgery, he showed hemiparesis, and brain imaging revealed chronic EDH at the location of the remnant acute hematoma. We performed surgery again to treat chronic EDH through a large craniotomy. Although many cases of EDH are self-limited, clinicians must keep in mind that some cases of EDH, especially those of venous origin and arising in young people, can become chronic and require surgical treatment.

• The Bulletin of The Korean Astronomical Society
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• v.29 no.2
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• pp.38.2-38.2
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• 2004

• The Bulletin of The Korean Astronomical Society
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• v.20
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• pp.5.2-5.2
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• 1995

• The Bulletin of The Korean Astronomical Society
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• v.18
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• pp.11-12
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• 1993

• The Bulletin of The Korean Astronomical Society
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• v.18
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• pp.24.2-25
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• 1993

• 대한관절경학회:학술대회논문집
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• 2006.11a
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• pp.102-103
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• 2006