• Journal of Korean Institute of Fire Investigation
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• v.11 no.1
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• pp.66-73
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• 2008

In this research, the electric power consumptions of the electrical machinery and appliances selected in the Seoul division of Korea Electrical Safety Corporation were measured. The power-saving efficiency was investigated by comparing the amounts of the reserved electric power when the Saver was on or off through measuring that of the reserved electric power before and after equipping the selected appliances with the Saver, a cutoff of the reserved electric power. As a result, the power-saving efficiency was around 18% when the Saver was installed. It can be ascribed to the removal of the source wasting electrical energy. Furthermore, by blocking the reserved electric power, the electric fire can be originally prevented and also the life time of the electrical machinery and appliances can be postponed.

• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.329-334
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• 2002

우리나라 전력계통의 특성상 남부의 전원단과 수도권의 부하중심단과의 거리가 존재하여 안정적인 계통전압제어에 어려움이 존재한다. 이러한 계통전압제어의 어려움을 극복하기 위해 154kV 계통에 SC Bank를 설치 운용중에 있다. 운전 환경상 차단기의 투입과 차단이 잦은 154kV SC Bank에 리액터가 소손되는 등의 문제점이 발생하고 있어 154kV SC Bank의 써지응답특성을 규명하고 차단기의 투입차단시 발생하는 써지전류의 저감에 대한 연구의 필요성이 대두되고 있다. 본 연구에서는 154kV SC Bank를 대상으로하여 현장조사와 현장실증을 통해 써지전류를 측정하고, 모의를 통해 써지응답특성을 규명하였다. 그 결과, 차단기의 접점의 상태와 피뢰기의 동작여부에 의해 써지전류가 크게 영향을 받는다는 점을 확인하였다. 154kV SV Bank를 대상으로 한 현장시험과 서지응답특성의 분석결과를 기본으로 하여 피뢰기의 영향과 차단기의 투입차단 영향을 최소화하는 방안으로 피뢰기의 분리운전으로 전류재단현상을 막아 급준써지전류의 발생을 억제하고 저항투압방식의 차단기로 써지전류를 30%이하로 억제할 수 있음을 실증과 모의로 확인하였다.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.4
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• pp.38-51
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• 2015

In the maps of the period, there were three large ponds called Dongji(東池), Seoji(西池) and Namji(南池) in Hanyang, the capital of Joseon Dynasty. They were different than the ponds found in the palace, civic buildings, and private dwellings. Dongji, Seoji and Namji were ponds relating to Fortress wall of Seoul, and all had lotuses cultivated in them. The purpose of this paper is to clarify the locational and spatial characteristics of these ponds and to detail the construction and reconstruction process and management conditions through maps, drawings, illustrations, historical records and literary works from the urban environmental perspective. The results are as follows. First, Seoji and Namji were intended for Bibo(裨補) which redeemed the geographical weaknesses of Hanyang, securement of bright court water(明堂水), supplement for fire energy(火氣), fire preventive water and waterscape facilities, while Dongji was emphasized on protecting water mouth(水口) besides Bibo and securement of bright court water. Second, Seoji was connected to mountain streams and Dongji and Namji were to ditches. The ponds connected to ditches had been difficult to fill and maintain. Third, Seoji and Namji were in urban areas, whereas Dongji was in farmlands, and these locational differences had an influence on the use of ponds. Fourth, the shapes of ponds, in contrast to the ponds in palace and civic buildings, which were perfectly square, were either freeform or square with rounded edges. Fifth, lotus ponds could be maintained by continuous management polices, earth filling and reconstructing process were repeated during the Joseon Dynasty. The lotus ponds of Fortress Wall of Seoul which had managed over 500 years, were built in, in accordance with the tenets of Bibo pungsu geomancy; however as time passed, they were maintained not only as public open spaces, but also a cultural attraction for residents and visitors.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.10
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• pp.66-72
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• 2007

This paper describes the characteristics of power loss and leakage currents flowing through new and used 18[kV] zinc oxide(ZnO) surge arrester under the mixed DC and AC voltages. The mixed DC and AC voltage generator of 50[kV] peak was designed and fabricated. The I-V curves of ZnO surge arrester were measured as a function of the voltage ratio K. The I-V curves under the mixed DC and AC voltages lay between the pure DC and AC characteristics, and the cross-over phenomenon in both I-V curves and R-V curves was observed at the low current region. As a result, the increase of DC component in the mixed voltages causes the increase of resistive component of total leakage current of ZnO surge arrester. Also, in the case of same applied voltage, the leakage current flowing through the used ZnO surge arrester was higher than that of the new ZnO surge arrester.

• Journal of Yeungnam Medical Science
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• v.31 no.2
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• pp.89-93
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• 2014

Background: This study was conducted to investigate the epidemiological features, clinical courses, and diagnoses of neonates who are transferred to neonatal intensive care unit of Yeungnam University Hospital due to tachypnea soon after birth. Methods: Based on medical records, we performed a retrospective study of neonatal intensive care unit admissions due to tachypnea from January 2010 to December 2013. Results: A total of 311 neonates were included in this study. The patient characteristics showed male predominance at 2.65:1. Among the 311 neonates with tachypnea, 127 (40.8%) neonates needed oxygen supply, and 54 (17.4%) neonates needed assisted mechanical ventilation. Transient tachypnea of the newborns (TTN) (158, 50.8%) showed the highest incidence, followed by pneumonia (63, 20.3%), extrapulmonary infection (37, 11.9%), respiratory distress syndrome (21, 6.8%), air leak (16, 5.1%), meconium aspiration syndrome (12, 3.9%), congenital heart disease (5, 1.6%), metabolic acidosis (3, 1%), primary pulmonary hypertension of newborns (2, 0.6%) and anemia (2, 0.6%). Conclusion: Although the neonates with tachypnea showed no other respiratory distress symptom, clinicians should be aware of the possibility of other pulmonary diseases as well as TTN and their extra-pulmonary causes. If tachypnea does not improve within a few hours, the clinician should consider further evaluation and management as soon as possible.

• Clinical and Experimental Pediatrics
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• v.48 no.7
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• pp.731-736
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• 2005

Purpose : Acute pyogenic osteomyelitis is uncommon in children. Delayed diagnosis and inappropriate treatment are leading to growth failure and deformation. We review the clinical manifestations and treatment of acute osteomyelitis in children according to age. Methods : A retrospective analysis was made of 32 patients who underwent antibiotic management or operation between Aug 1989 and Dec 2003 for acute pyogenic osteomyelitis in age from 0 to 15 years old. Results : The study group was composed of 21 boys and 11 girls. The subjects were divided into four groups according to age : 0-1 yr(n=6), 1-5 yr(n=11), 6-10 yr(n=8), and 11-15 yr(n=7). Nineteen cases were diagnosed in Winter. Femur was the most common infected site(37.5%). There were no predisposing factor in 17 patients, and 7 of 15 patients had trauma history. Sepsis was important predisposing factor in neonates. The chief complaints were pain, swelling and fever. S. aureus(61%) is the most common organism. Twenty-nine patients were treated with operation and concomitant antibiotics. Two cases had sequelae in follow-up period : One is avascular necrosis of femur and the other is discrepancy of leg length. Conclusion : In our review, because of poor prognosis in septic neonates, we recommend to treat actively neonatal sepsis and prevent or detect osteomyelitis early. Because most of patients were diagnosed and treated in orthopedic surgery, the rate of operation was too high. So, protocol for further evaluation and management of acute osteomyelitis in pediatric patients were needed.