• 터널과지하공간
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• 제17권4호
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• pp.301-310
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• 2007

심부 탄광 개발의 타당성 검토나 통기계획 수립시 갱내 작업장의 온도를 예측하는 것은 매우 중요하다. 심부의 탄광주변의 암반은 매우 다양하고 여러 암종으로 구성되어 있어 암반의 열 전도율(thermal conductivity)를 구하는 일은 매우 어려운 작업이다. 이에 본 연구에서는 복잡한 갱내여건에 상응한 열전도율을 도출하기 위해 artificial neural network(인공신경망)를 새롭게 도입하여 갱내 기상 예측을 위한 전산 프로그램을 개발하였다. 인공 신경망을 이용한 열전도율 계산 프로그램은 back-propagation algorithm을 사용하였으며 9개의 인자를 받아들이는 input layer와 5개와 3개의 뉴런을 가지는 두 개의 hidden layer로 구성되어져 있다. 개발된 TemPredict를 이용하여 장성광업소의 심부온도를 검증한 결과 장성생산부 -300 ML 하반구 입구의 온도가 $25.65^{\circ}C$로 산출되었고 실제 온도($25.7^{\circ}C$)와 $0.05^{\circ}C$의 차이를 나타냈다. 이는 오차 범위 5% 이내에 포함되는 것으로 검증결과 95% 이상의 높은 신뢰도를 나타냈다. 위의 검증결과를 통해 TemPredict를 이용하여 현재 굴진중인 -425 ML이 관통이 되었을때의 장성생산부 주운반갱도 9X지점의 온도를 예측하였다. 예측 결과 장성생산부 주운반갱도 9X지점의 온도는 $28.2^{\circ}C$로 예측되었다. 향후 TemPredict를 통한 온도예측을 통하여 광산이나 지하구조물의 설계시 통기계획에 많은 도움을 줄 것으로 기대된다.

• Wind and Structures
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• 제34권4호
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• pp.321-334
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• 2022

Irregularity in plan shape is very common for any type of building as it enhances better air ventilation for the inhabitants. Systematic opening at the middle of the facades makes the appearance of the building plan as a butterfly one. The primary focus of this study is to forecast the force, moment and torsional coefficient of a butterfly plan shaped tall building. Initially, Computational Fluid Dynamics (CFD) study is done on the building model based on Reynolds averaged Navier Stokes (RANS) k-epsilon turbulence model. Fifty random cases of irregularity and angle of attack (AOA) are selected, and the results from these cases are utilised for developing the surrogate models. Parametric equations are predicted for all these aerodynamic coefficients, and the training of these outcomes are also done for developing Artificial Neural Networks (ANN). After achieving the target acceptance criteria, the observed results are compared with the primary CFD data. Both parametric equations and ANN matched very well with the obtained data. The results are further utilised for discussing the effects of irregularity on the most critical wind condition.

• Tuberculosis and Respiratory Diseases
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• 제79권4호
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• pp.214-233
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• 2016

There is no well-stated practical guideline for mechanically ventilated patients with or without acute respiratory distress syndrome (ARDS). We generate strong (1) and weak (2) grade of recommendations based on high (A), moderate (B) and low (C) grade in the quality of evidence. In patients with ARDS, we recommend low tidal volume ventilation (1A) and prone position if it is not contraindicated (1B) to reduce their mortality. However, we did not support high-frequency oscillatory ventilation (1B) and inhaled nitric oxide (1A) as a standard treatment. We also suggest high positive end-expiratory pressure (2B), extracorporeal membrane oxygenation as a rescue therapy (2C), and neuromuscular blockage for 48 hours after starting mechanical ventilation (2B). The application of recruitment maneuver may reduce mortality (2B), however, the use of systemic steroids cannot reduce mortality (2B). In mechanically ventilated patients, we recommend light sedation (1B) and low tidal volume even without ARDS (1B) and suggest lung protective ventilation strategy during the operation to lower the incidence of lung complications including ARDS (2B). Early tracheostomy in mechanically ventilated patients can be performed only in limited patients (2A). In conclusion, of 12 recommendations, nine were in the management of ARDS, and three for mechanically ventilated patients.

• Journal of Yeungnam Medical Science
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• 제6권2호
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• pp.47-55
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• 1989

고빈도 진동환기가 동맥혈의 가스분압에 미치는 영향을 알아보고자 저자들은 9마리의 고양이를 대상으로 진동빈도, 일회분출량 및 bias flow를 다양하게 변화시켜 아래와 같은 결과를 얻었다. 1) 일회분출량과 bias flow를 고정시킨 후 진동빈도를 점차 증가시켜 도 $PaCO_2$의 변동은 없었다(Table 1). 2) 진동빈도를 고정시킨 후 일회분출량과 bias flow를 변화시켜 관찰하였던 바 $PaCO_2$는 bias flow의 변화와는 상관관계가 없으나, 일회분출량의 변화와는 유의한 상관관계가 있었다(p<0.01)(Table 2, Fig. 1). 3) $PaCO_2$는 진동빈도를 15Hz로 고정시킨 상태하에서는 1회 분출량 및 bias flow를 증가시켜도 큰 변동없이 정상으로 유지되었다(Table 2). 이상의 결과로 고빈도 진동환기법에서 $PaCO_2$의 결정인자는 진동빈도와 bias flow와는 무관하였고 일회분출량과는 상관관계가 있음을 알 수 있었다.

• 터널과지하공간
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• 제13권6호
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• pp.434-443
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• 2003

본 연구에서는 비서형 모델에 적용 가능한 역전파 알고리즘을 이용하여 도로터널에서 발생하는 오염물질을 예측하기 위한 인공신경망을 개발하였다. 도로 터널에서 중요시되는 오염인자는 CO농도와 가시도이므로, 인공신경망의 구성을 각각의 독립적인 네트워크로서 구성하였다. 사용한 입력데이터는 영동고속도로에 위치한 종류식 환기 방식을 채택한 일방향 2차선 도로 터널 2개소에서 실측한 데이터를 사용하였다. 예측치와 실측치를 비교할 때 인공신경망의 학습도는 약 95%의 정확성을 보이는 것으로 나타났다. 분석결과 개발된 인공신경망에 의한 결과는 PIARC 방식에 의한 계산치 보다 약 5배 정도의 정확성을 보였다. 특히 주행속도가 낮을 경우 더 높은 정확도를 나타낼 것으로 기대 되었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1129-1130
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• 2011

The output of small hydro power plant was generated less than rated output under high temperature. We Installed the artificial ventilation that blow cold wind from water supply pipe tunnel to small hydro power plant. The temperature of small hydro power has been decreased. The output of small hydro power plant has been increased from 405kW to 445kW.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.2053-2054
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• 2011

Cardiopulmonary resuscitation(CPR) is performed by artificial ventilation and thoracic compression for the patient under emergent situation to maintain at least the minimum level of respiration and blood circulation for life survival. Good quality CPR requires monitoring respiration. We developed a system for continuous monitoring respirational signal while CPR, using respirational airflow sensor for CPR. Signal extraction circuit obtains pressure signal while CPR. Obtained signal would be performed analog-digital conversion and changed to airflow value by characteristic formula. Single inspiration and expiration were considered a period. Detected valid data were displayed LCD.

• Clinical and Experimental Pediatrics
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• 제52권8호
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• pp.856-861
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• 2009

Cardiopulmonary arrest has long been accepted as an unquestionable definition of death. An advent of cardiopulmonary resuscitation and artificial ventilation along with the development of organ transplantation has prompted the emergence of the concept of brain death. The criteria for brain death are based mainly on the clinical examination of coma, apnea and total loss of brain stem function. Although organ transplantation by donor brain death has increased in Korea over recent years, there is still a substantial shortage of donor organs compared to the demand. Improvement of government policies and changes of social culture for organ donation are needed for the activation of organ transplantation by donor brain death. Pediatricians have an important role for the search of potential donors in cases of brain death and optimal medical care for successful organ transplantation.

• 한국가금학회지
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• 제20권1호
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• pp.11-15
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• 1993

Environmental measurements were made in 10 broiler confinement houses in order to characterize dust contaminants. Particles were collected by filters on nine stages Anderson Air Sampler, The obtained results were summarized as follows ; 1. The concentrations of the total suspended particles(TSP) were 7.584 mg/$m_3$~11.589mg/$m_3$ in 10 day old broiler houses and 15.836 mg/$m_3$~22.471 mg/$m_3$ in 30 day old broiler houses. 2. The concentrations of the coarse particles were 4.974 mg/$m_3$~18.981 mg/$m_3$ in 10 broiler confinement houses. Therefore, it was found that the coarse particles contributed to TSP between 65.6% and 85.0%. 3. The dust levels were higher in 30 day old broiler houses with TSP averaging about 19.341 mg/$m_3$ than 9.491 mg/$m_3$ in 10 day old broiler houses. In view of the above results , It was concluded that domestic broiler houses need artificial ventilation system.

• Asian-Australasian Journal of Animal Sciences
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• 제6권2호
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• pp.305-311
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• 1993

A total of thirty male Holstein calves were reared outdoors with simple housings or in warmed pens in three experiments conducted in three consecutive midwinters in Hokkaido. Average outdoor air temperatures during the experiments were between -5.3 and $-6.1^{\circ}C$, and average minimum air temperatures were between -9.7 and $-10.6^{\circ}C$. The age of calves at the start of the experiments were $16{\pm}6$ hours. There was no difference in the liquid feed intake, while the solid concentrate (artificial milk) intake by the calves in the simple housing systems (outdoors, calf hutch and open shed) tended to be higher than those in the warmed pen. No significant differences in the daily gain or the monthly development of wither height were observed among housing systems. There were no serious cases of diarrhea. However, coughing was observed in several of the calves reared in the poorly ventilated warmed pens.