• The Journal of Korea Assosiation for Disability and Oral Health
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• v.13 no.1
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• pp.47-51
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• 2017

Haddad syndrome, the association of Congenital Central Hypoventilation Syndrome (CCHS) and Hirschsprung's disease (HD), is a disease caused by mutation of PHOX2B gene. This disease, which occurs very rarely worldwide, is characterized by adequate ventilation during wakefulness and hypoventilation during sleep due to decreased ventilatory sensitivity. In this case report, we report a case of dental treatment under general anesthesia in a child with Haddad syndrome. A 3-year-old child with Haddad syndrome visited Seoul National University Dental Hospital for dental treatment. Dental treatment was planned under general anesthesia because of his medical condition. Treatment was successfully done without any postoperative complications. This case suggests that general anesthesia may be advantageous for dental treatment due to the risk of respiratory depression in a child with Haddad syndrome.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1996.10b
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• pp.98-103
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• 1996

석탄가스화복합발전소내 공기분리장치와 연계된 가스터빈 공기압축기의 성능병화를 예측할 수 있는 해석방법을 제안하였다. 공기분리장치와 연계된 가스터빈용 공기압축기의 성능변화는 유선곡률방법과 압력손실모델을 결합한 해석방법을 사용하였으며, 예측결과들을 실제 압축기성능 시험 결과와 비교하여 예측정확도를 검증하였다. 제안된 압축기성능 해석방법을 근간으로, 압축기와 공기분리장치의 연계조건인 열교환기의 핀치포인트 온도차, 추출공기량 및 추출 공기압력이 압축기 성능변화에 미치는 영향을 정량적으로 예측하였다. 공기추출량이 늘어나거나 핀치포인트 온도차가 커질수록, 압축기의 압축비 및 소요동력은 증가하나, 압축기 효율은 공기추출량의 증가에 따라 고압공기추출시에는 저하되고, 저압공기추출시에는 향상되었다. 더 나아가, 압축기의 일반화된 성능특성곡선의 제시를 통해, 압축기 효율을 극대화 할 수 있는 압축기/공기분리장치 간 연계조건의 최적화를 시도하였다.

• KOREAN POULTRY JOURNAL
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• v.36 no.9 s.419
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• pp.108-111
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• 2004

10년만에 찾아온 지난 여름 무더위는 양계인들에게 큰 어려움을 안겨주었다. 단열과 환기를 완벽하게 한 농장이라도 외부에서 들어오는 바람 자체의 온기로 계사 내부의 온도를 낮추는데는 한계가 있었다는 반응들이다. 혹서로 인해 전국적으로 $20\%$정도의 생산성이 감소하면서 난가도 8월 25일 현재 129원(서울경기발표기준)이라는 사상 초유의 가격이 형성되면서 계란을 구하기에 급급한 유통상인들의 움직임을 감지할 수 있었다. 그러나 금년 3차례에 걸친 사료가격 인상과 더위로 인한 산란율 저하, 폐사 등으로 실질적인 농가소득은 그리 크지 않은 것으로 나타나고 있다. 문제는 이 같은 가격이 언제까지 유지되어줄 것인지, 고병원성가금인플루엔자 등 질병이 언제 농장에 급습할지 등에 항상 불안한 마음으로 양계를 해야하는 것이 현 실정인 것이다. 따라서 본고는 어려운 주변 여건에도 불구하고 양계업을 천직으로 알고 채란업을 묵묵히 경영하고 있는 배로농장(대표 나상화, 52)을 찾아 고품질의 계란생산 방법 등 농장경영 현황을 들어보았다.

• Journal of Bio-Environment Control
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• v.7 no.4
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• pp.311-323
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• 1998

This study was conducted to analyze the temperature characteristics under tunnel type greenhouse to cultivate watermelon in Sungju region. Air temperature of tunnel type greenhouse was descending rapidly after sunset, and the time required the air temperature inside greenhouse nearly reached the outside air temperature was about 2.5 hours. The maximum air temperature in tunnel type greenhouse, in case of high air temperature day, was exceeding 4$0^{\circ}C$ during day time. Air temperature inside greenhouse during night time could sustain about 2~3$^{\circ}C$ higher than the outside air temperature. But it was necessary to supply supplemental heat when the air temperature was below optimum growth temperature. Soil temperature in the depth of 20cm under soil surface could maintain higher than 2$0^{\circ}C$ and the variation range in a day was 3~5$^{\circ}C$, and the soil temperature descending due to irrigation was about 5~6$^{\circ}C$.

• Tuberculosis and Respiratory Diseases
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• v.53 no.6
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• pp.619-634
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• 2002

Background : Many inflammatory mediators and collagenases are involved in the pathogenesis of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). The increase of matrix metalloproteinase-9 (MMP-9, gelatinase-B) produced mainly by inflammatory cells was reported in many ALI models and connective tissue cells. In this study, the expression of MMP-9 in ventilator-induced lung injury (VILI) model and the effects of matrix metalloproteinase inhibitor (MMPI) on VILI were investigated. Methods : Eighteen Sprague-Dawley rats were divided into three groups: low tidal Volume (LVT, 7mL/Kg tidal volume, 3 $cmH_2O$ PEEP, 40/min), high tidal volume (HVT, 30mL/Kg tidal volume, no PEEP, 40/min) and high tidal volume with MMPI (HVT+MMPI) groups. Mechanical ventilation was performed in room air for 2 hours. The 20 mg/Kg of CMT-3 (chemically modified tetracycline-3, 6-demethyl 6-deoxy 4-dedimethylamino tetracycline) was gavaged as MMPI from three days before mechanical ventilation. The degree of lung injury was measured with wet-to-dry weight ratio and acute lung injury score. Expression of MMP-9 was studied by immunohistochemical stain with a mouse monoclonal anti-rat MMP-9 $IgG_1$. Results : In the LVT, HVT and HVT+MMPI groups, the wet-to-dry weight ratio was $4.70{\pm}0.14$, $6.82{\pm}1.28$ and $4.92{\pm}0.98$, respectively. In the HVT group, the ratio was significantly higher than other groups (p<0.05). Acute lung injury score measured by five-point scale was $3.25{\pm}1.17$, $12.83{\pm}1.17$ and $4.67{\pm}0.52$, respectively. The HVT group was significantly damaged by VILI and MMPI protects injuries by mechanical ventilation (p<0.05). Expression of MMP-9 measured by four-point scale was $3.33{\pm}2.07$, $12.17{\pm}2.79$ and $3.60{\pm}1.95$, respectively, which were significantly higher in the HVT group (p<0.05). Conclusion : VILI increases significantly the expression of MMP-9 and MMPI prevents lung injury induced by mechanical ventilation through the inhibition of MMP-9.

• Journal of Animal Environmental Science
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• v.17 no.sup
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• pp.43-50
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• 2011

This study was conducted to verify the effect of chlorine dioxide ($ClO_2$) on odor reduction at a commercial swine facility consisting of a windowless piglet barn and a grower/fattening barn. The windowless piglet barn used a duct ventilation system. Air velocity at very below the upper duct was 4.53 m/s. Air velocity at the lower space around the living space of pigs in the grower/fattening barn was 0.26 m/s. $NH_3$ concentration was around 9ppm and less than 3 ppm before and after the $ClO_2$ spraying, respectively, which was over 70% reduction. There was no $H_2S$ detection. $NH_3$ concentrations measured in the windowless grower/fattening barn and at the exhausted air were 26 ppm and 11ppm, respectively. $NH_3$ concentration at a biocurtain outside was less than 1 ppm. Hence, $ClO_2$ spraying at windowless barns was effectively decreased malodor such as $NH_3$.

• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.4
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• pp.387-394
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• 2009

The objective of this study is to evaluate the durability and deterioration of concrete lining in the seven conventional tunnels. These tunnels were constructed about 40~70 years ago, and closed about 10~40 years ago. The field investigation and various laboratory testings were performed for this study. It was observed from the visual, examinations that the concrete linings of 7 tunnels were severely deteriorated, such as, cracks, leakages, desquamation, and exploitations. The compressive strengths obtained from rebound hardness method and uniaxial compressive strength test on core specimens largely differed depending on the locations in the tunnel. The maximum compressive strength of concrete lining was greater about 2 times than the minimum compressive strength of concrete lining in the same tunnel. The results of micro-structural analysis showed that the substances deteriorating the concrete lining, such as ettringite and thaumasite, were detected in the concrete lining of tunnel.

• Radiation Oncology Journal
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• v.23 no.4
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• pp.243-252
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• 2005

Purpose: Indoor air quality (IAQ) in the radiation treatment center which is generally located underground is important to the health of hospital workers and patients treated over a long period of time. this study was conducted to measure and analyze the factors related to IAQ and subjective symptoms of sick building syndrome, and to establish the causes influencing IAQ and find a solution to the problems. Methods and Materials : Self administrated questionnaire was conducted to check the workers' symptoms and understanding of the work environment. Based on a preliminary investigation, the factors related to IAQ such as temperature, humidity, fine particulate. carbon dioxide, carbon monoxide, formaldehyde, total volatile organic compounds (TVOC), and radon gas were selected and measured for a certain period of time in specific sites where hospital workers stay long in a day. And we also evaluated the surrounding environment and the efficiency of the ventilating system simultaneously, and measured the same factors at the first floor (outdoor) to compare with outdoor all quality, All collected data were assessed by the recommended standard for IAQ of the domestic and international environmental organizations. Results: Hospital workers were discontented with foul odors, humidity and particulate. They complained symptoms related to musculo-skeletal system, neurologic system, and mucosal-irritatation. Most of the factors were not greater than the recommended standard, but the level of TVOC was third or fourth times as much as the measuring level of some offices in the United States. The frequency and the amount of the ventilating system were adequate, however, the problem arising in the position of outdoor-air inlets and indoor-air outlets involved a risk of the indraft of contaminated air. A careful attention was a requirement in handling and keeping chemical substances including a developing solution which has a risk of TVOC emissions, and repositioning the ventilating system was needed to solve the contaminated-air circulation immediately Conclusion We verified that some IAQ-related factors and inadequate ventilating system could cause subjective symptoms in hospital workers. The evaluation of IAQ was surely needed to improve the underground working environments for hospital workers and patients. On the basis of these data, from now on, we should actively engage in designs of the department of radiation oncology or improvement in environments of the existing facilities.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.8
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• pp.1219-1226
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• 2013

This study is the analysis and verification process of the L-band satellite communications repeater thought PCB & circuit EM analysis. System performance can be vulnerable to various spurious inside the L-band satellite transponder, power conversion board, digital signal board, TM/TC board, such as control panels and blocks that are linked signal components when the winch is increased due to the noise component. So the whole system can cause performance degradation. PCB resonance analysis and EM simulation can be easily analyzed for a variety of optimal. Also, by setting the ports on the PCB, H/W designer wants to can easily analyze system.

• Clinical and Experimental Pediatrics
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• v.52 no.12
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• pp.1392-1395
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• 2009

Pulmonary vascular air embolism is a rare and, universally, almost a fatal complication of positive pressure ventilation in newborn infants. Here, we report a case of this unusual complication in a very-low-birth-weight infant who showed the clinical and radiological features of this complication along with pulmonary hypoplasia and massive hydrops. The possible pathogenesis has been discussed and a brief review of related literature has been presented.