• 한국화재소방학회논문지
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• 제32권6호
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• pp.15-21
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• 2018

본 연구에서는 급기가압 조건에서 거실, 부속실 및 계단실로 구성된 복합 구획 공간에 대해 화재해석을 수행하고 가압 및 환기 조건에 따른 화재 연기의 유동 특성을 분석하였다. 화재 해석은 유효누설면적을 측정하기 위해 제작된 누기율 시험설비에 대하여 수행하였으며, 화재의 거시적 특성과 각 구획에 대한 유동 및 압력 특성의 분석을 통해 급기가압 조건에서의 화염 및 연기 거동에 대한 이해를 증진시키고자 하였다. 화재 해석 결과는 화재 발열량의 크기가 환기 시스템에 의해 공급되는 공기량에 의해서 민감하게 영향을 받게 됨을 보여주었다. 거실과 부속실에서의 속도분포 분석 결과를 통해 급기가압의 조건에서도 화재 연기가 문의 상층부를 통해 부속실로 유출될 수 있음을 확인하였다. 이를 통하여 급기가압 제연시스템의 설계와 적용에 있어서 화재 크기와 공간적 특성과 같은 요인을 고려하는 것이 매우 중요하다는 것을 확인할 수 있었다.

• 대한기관식도과학회지
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• 제17권2호
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• pp.83-88
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• 2011

Robotic thyroidectomy has been developed to minimize neck scarring, and several authors have described its feasibility and safety, and have reported surgical outcomes comparable with conventional open thyroidectomy. The da Vinci surgical system robot provides a three-dimensional $10-12{\times}$magnified view of the surgical area. It also provides hand-tremor filtration, fine motion scaling, and precise and multi-articulated hand-like motions. Recently, robotic technology has also been applied to lateral compartment neck dissection in thyroid cancer. We have developed a new novel selective neck dissection procedure by a gasless unilateral axillo-breast (GUAB) approach with a da Vinci Surgical System for well-differentiated thyroid carcinoma to avoid a long visible neck scar. Based on our early experience, robotic selective neck dissection by GUAB approach is a safe, feasible and cosmetically excellent procedure. It can be an alternative to conventional open surgery in the highly selected patients with well-differentiated thyroid carcinoma. The oncologic safety of robotic selective neck dissection should be verified with long-term follow-up data.

• Advances in aircraft and spacecraft science
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• 제3권1호
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• pp.77-93
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• 2016

In this paper, a zero-dimensional mathematical formulation for rapid and explosive decompression analyses of pressurized aircraft is developed. Air flows between two compartments and between the damaged compartment and external ambient are modeled by assuming an adiabatic, reversible transformation. Both supercritical and subcritical decompressions are considered, and the attention focuses on intercompartment venting systems. In particular, passive and active vents are addressed, and mathematical models of both swinging and translational blowout panels are provided. A numerical procedure based on an explicit Euler integration scheme is also discussed for multi-compartment aircraft analysis. Various numerical solutions are presented, which highlight the importance of considering the opening dynamics of blowout panels. The comparisons with the results from the literature demonstrate the validity of the proposed methodology, which can be also applied, with no lack of accuracy, to the decompression analysis of spacecraft.

• 한국안전학회지
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• 제35권4호
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• pp.32-39
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• 2020

The fire compartments with fire-resistant construction are installed in the principal structural parts of a building in order to reduce damage in the event of a building fire. As a fire may spread through a crack in the fire compartment, the firestop with secured performance is used according to the procedure, methods, and standards specified in the detailed operation guideline. According to the current detailed operation guideline, vertical members (wall penetration) and horizontal members (floor penetration) are classified into different categories respective to each other for the classification of the firestop. Therefore, an accreditation applicant must apply for the performance test for each structure even if the wall and the floor have the same structure. Also, Grade T is used for the firestop that penetrates the fire compartment. However, in the case of foreign countries, the use of Grade F for the firestop is allowed even if it penetrates the fire compartment. The result of the precedent studies also showed that there was a significantly low possibility of fire to spread even if Grade F was applied for a metallic duct that penetrated the fire compartment. In this study, the improved scheme for the classification and performance standard of firestops was presented by analyzing the results of precedent studies regarding the firestop and domestic and overseas firestop qualification systems.

• 한국화재소방학회논문지
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• 제27권3호
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• pp.20-29
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• 2013

실규모 환기부족 구획화재에서 수직 개구부의 형상 및 위치변화에 따른 열 및 화학적 화재특성 변화를 수치적으로 검토하기 위하여, 이론적 최대 공기 유입량을 결정하는 환기인자($A\sqrt{h}$)와 heptane pool 화재의 질량 감소율이 모든 조건에 대하여 동일하게 설정되었다. 주요 결과로서, 출입문 형상의 변화는 구획 내부의 열 및 화학적특성 변화에 큰 영향을 미친다. 창문 위치의 변화는 화재지속시간 및 재순환 유동구조를 포함한 추가적인 화재특성의 복잡한 변화를 초래하였다. 이들 결과는 개구부 유동 및 연료/공기의 혼합현상을 포함한 다차원 유동 및 화재특성을 통해 상세히 분석되었다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 학술논문집
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• pp.228-228
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• 2004

Nuclear Environment Technology Institute (KHNP-NETEC) developed the conceptual design of the low and intermediate-level radioactive waste (LILW) repository. Among many engineering challenges, it is of particular importance to find out an optimum arrangement of near-surface disposal vaults in the repository area to minimize the radionuclide flux and concentration at the interface between the geo-sphere and bio-sphere. (omitted)

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2003년도 춘계학술논문발표회논문집
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• pp.259-264
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• 2003

The fire protection system of Nuclear Power Plants(NPPs) is an integrated system that is applied multi-field technology. So, it needs synthetic design and analysis, that is, the plan of fire protection, fire compartment, fire detection, fire suppression, and success of safety shut down, etc. In case of a fire in NPPs, secure the safety of reactor and minimize the radioactivity contamination. For this purpose, perform the fire risk analysis and make up the deducted problem through the improvement of design or the change of operation process.

• Environmental Engineering Research
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• 제14권1호
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• pp.53-60
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• 2009

The main objective was to develop and assess a dynamic fate and transport model for lead in air, soil, sediment, water and vegetation. Daejeon was chosen as the study area for its relatively high contamination and emission levels. The model was assessed by comparing model predictions with measured concentrations in multi-media and atmospheric deposition flux. Given a lead concentration in air, the model could predict the concentrations in water and soil within a factor of five. Sensitivity analysis indicated that effective compartment volumes, rain intensity, scavenging ratio, run off, and foliar uptake were critical to accurate model prediction. Important implications include that restriction of air emission may be necessary in the future to protect the soil quality objective as the contamination level in soil is predicted to steadily increase at the present emission level and that direct discharge of lead into the water body was insignificant as compared to atmospheric deposition fluxes. The results strongly indicated that atmospheric emission governs the quality of the whole environment. Use of the model developed in this study would provide quantitative and integrated understanding of the cross-media characteristics and assessment of the relationships of the contamination levels among the multi-media environment.

• 대한의용생체공학회:의공학회지
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• 제36권6호
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• pp.271-275
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• 2015

The aim of this study was to develop a multi-nozzle based bioprinting system for fabrication of three-dimensional (3D) biological structure. In this study, a thermoplastic biomaterial that has relatively high mechanical stability, polycaprolactone (PCL) was used to make the 3D structure. A multi-nozzle bioprinting system was designed to dispense thermoplastic biomaterial and hydrogel simultaneously. The system that consists of 3-axes of x-y-z motion control stage and a compartment for injection syringe control mounted on the stage has been developed. Also, it has 1-axis actuator for position change of nozzle. The controllability of the printed line width with PCL was tested as a representative performance index.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.547-550
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• 2006

An analysis method is developed for the prediction of venting in multiple compartments which are connected in series or parallel through multiple ports. The existing method by the authors is modified to remove the limitation in number of ports and compartments, and the more general polytropic relation or solution of the additional energy equation replaces the previous isentropic relation allowing the prediction of pressure rise in addition to pressure drop. The accuracy of the method is verified by comparison with the results by NASA Flap code for the problem of pressure drop in a payload in the Space Shuttle cargo bay. It is expected that this method will be a useful tool in prediction of the pressure variation in a payload or payload capsule without mentioning the payload fairing itself.