• 한국재난정보학회 논문집
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• 제9권2호
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• pp.178-187
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• 2013

16층 이상 고층아파트는 국가에서도 특수건물(Specific Buildings)로 지정하여 정기적인 화재안전점검과 보험가입을 의무화하는 등 특별관리를 하고 있다. 이 같은 배경에는 정부가 그동안에 고층아파트가 사고사례 경험상 화재위험에 매우 취약하다는 것을 인식하고 있으며, 아파트화재 사고건수, 아파트화재 피해액, 주택화재보험 손해율 등이 이 같은 인식을 뒷받침하고 있다. 본 연구에서는 고층아파트 화재위험에 대한 화재통계 분석, 아파트화재 보험의 가입 현황 및 고층아파트의 위험성 검토 등에 대하여 고찰하였다. 연구결과는 고층아파트 화재위험을 효율적으로 관리하기 위하여 이웃 세대로의 연소 확대위험 경감 방안마련, 피난 안전성 확보, 스프링클러 등 소방시설의 신뢰성 유지, 실질적 전부손해의 보상이 가능한 전부보험 가입, 화재대물배상책임보험 및 풍수재위험특약 가입 등을 주요 내용으로 하는 고층아파트의 종합적인 위험관리방안이 필요한 것으로 나타났다.

• 전기학회논문지
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• 제60권3호
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• pp.680-685
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• 2011

Nowadays, in metropolitan railroad, DC feeding system is being generally applied. In order to reduce damages of electro-chemical corrosion caused by stray current and leakage current, in DC feeding system, rail is used as negative-polarity return conductor for traction load current. However, it has problem of rail potential increase and there are no adequate measures to prevent it in domestic. In this paper, we presented fundamental theory and related standards about rail potential increase. And then, we analyzed field testing data and simulated a variety of operations by using PSCAD/EMTDC as an analysis program of power system. In addition, voltage control device is suggested to prevent accidents caused by rail potential increase.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 B
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• pp.1263-1265
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• 2001

This study presents accurate simulation to examine a reason rail potential rise and how to design ground connection(Cross Connection Cable, CCC) and draw up a plan of an optimal buried grounding system according to section.

• Smart Structures and Systems
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• 제11권5호
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• pp.435-451
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• 2013

High-rise buildings are a common feature of urban cities around the world. These flexible structures frequently exhibit large vibration due to strong winds and earthquakes. Structural control has been employed as an effective means to mitigate excessive responses; however, structural control mechanisms that can be used in tall buildings are limited primarily to mass and liquid dampers. An attractive alternative can be found in outrigger damping systems, where the bending deformation of the building is transformed into shear deformation across dampers placed between the outrigger and the perimeter columns. The outrigger system provides additional damping that can reduce structural responses, such as the floor displacements and accelerations. This paper investigates the potential of using smart dampers, specifically magnetorheological (MR) fluid dampers, in the outrigger system. First, a high-rise building is modeled to portray the St. Francis Shangri-La Place in Philippines. The optimal performance of the outrigger damping system for mitigation of seismic responses in terms of damper size and location also is subsequently evaluated. The efficacy of the semi-active damped outrigger system is finally verified through numerical simulation.

• 한국수소및신에너지학회논문집
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• 제21권2호
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• pp.129-135
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• 2010

Homogeneous charge compression ignition (HCCI) engines have the potential to provide both diesel-like efficiency and very low emissions of nitrogen oxide (NOx) and particulate matter(PM). However, several technical issues still must be resolved before HCCI can see application. Among these, steep pressure-rise rate which leads to narrow operating range of HCCI engine continues to be a major issue. This work investigates the combination of two methods to mitigate the excessive pressure-rise rates at high power output, namely fuel stratification and Cooled exhaust-gas recirculation (Cooled EGR), after identifying the each effects to pressure-rise rate. When applying the fuel stratification to simulation, total fuelling width of 0.15 at BDC is set as a equivalent ratio difference based on the previous research. In order to simulate the effects of cooled EGR, $CO_2$ mole fraction in pre-mixture is changed ranging from 0 to 30%. DME which has a characteristic of two-stage ignition is used as a fuel.

• 한국가스학회지
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• 제13권6호
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• pp.21-28
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• 2009

본 연구의 목적은 온도 성층화와 농도 성층화의 효과가 HCCI 연소에서 압력상승률 저감과 배기가스에 어떤 영향을 미치는지 알아보는 것이다. 2단계 열발생이 생기는 디메틸에테르(Di-Methyl Ether, DME) 연료를 사용하였다. 수치계산은 멀티 존 모델과 상세 화학 반응 스킴을 이용하였다. 수치계산 결과, 온도 성층화와 농도 성층화는 연소기간을 길게 하여 압력상승률을 저감시키는 것을 확인하였다. 그러나 농도 성층화의 폭이 너무 커지면 오히려 일산화탄소와 질소산화물이 증가하였으며, 연소 효율은 감소하였다.

• 국제초고층학회논문집
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• 제8권2호
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• pp.95-100
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• 2019

Whilst most research focuses on the reduction of operative energy use in buildings, the aspect of which (and how many) materials are used is often neglected and poorly explored. However, considering the continuous growth of the global population and the limited availability of resources, it is clear that focusing on operative energy alone is too short-sighted. The tasks lying ahead for architects and engineers cannot be accomplished with conventional methods of construction. With a share of 50-60% of global resource consumption, the building industry has a decisive impact on our environment. If business as usual continues, resources will be significantly depleted in a matter of decades. Therefore, researchers of the University of Stuttgart are investigating the concept of adaptivity as a promising method for saving resources in the built environment. The term adaptivity in the context of building structures was first introduced by Werner Sobek. It describes a method where sensors, actuators and control units are implemented in systems or facades in order to oppose physical impacts in an ideal way. The applicability of this method will be verified on an experimental high-rise building at the University campus in Stuttgart. Thus, this paper describes this innovative research project and depicts the concept of adaptivity in high-rise structures. Furthermore, it gives an overview of potential actuation concepts and the interdisciplinary challenges behind them.

• Architectural research
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• 제22권4호
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• pp.105-112
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• 2020

The purpose of this study is to establish a method for assessing a building's risk against disaster, tentatively named the Korean integrated disaster evaluation simulator (K-IDES). Based on previous studies, FEMA's risk management series and FEMA IRVS are selected as case studies for developing a frame work of K-IDES, through the comparative analysis of domestic building design guides, codes, and special acts related to disasters, in order to develop a risk assessment methodology for quantitative results. The assessment method consists of a classification system and calculating risk, and a simulation applying the developed checklist in K-IDES to similar types of high-rise buildings will be conducted to validate its accuracy. The final goal is to systemize an integrated risk management in a high-rise building against disasters for the purpose of recognizing vulnerable areas from the beginning of the design process and reinforcing it from potential threats after construction.

• 한국항해항만학회지
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• 제37권4호
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• pp.409-418
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• 2013

기후변화로 인한 해수면 상승이 우리나라 연안에 장기적으로 큰 영향을 줄 것으로 예측되어 다양한 방법을 사용하여 연안에 대한 해수면 상승의 취약성 평가가 이루어지고 있다. 본 연구에서는 사면이 바다와 접해 해수에 의한 침수가 빈번하여 향후 해수면 상승에 의한 피해가 클 것으로 예상되는 부산의 영도 해안을 대상으로 해수면 상승이 해안에 미치는 영향을 알아보고 그 대책을 마련하였다. 먼저 잠재적 해수면 상승률을 바탕으로 CAD를 이용한 해수면 상승 시뮬레이션을 실시하였으며 다음으로 시뮬레이션결과를 바탕으로 침수범위와 재해위험 지역을 종합적으로 고려하여 피해 예상지역을 추출하였고 최종적으로 침수특성에 따라 지구별로 세분하여 해당 지구에 적합한 대응전략을 수립하였다.

• Structural Engineering and Mechanics
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• 제78권3호
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• pp.305-317
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• 2021

An AMD control system is usually built based on the original model of a target building. As a result, the fact leads a large calculation workload exists. Therefore, the orders of a structural model should be reduced appropriately. Among various model-reduction methods, a suitable reduced-order model is important to high-rise buildings. Meanwhile, a partial structural information is discarded directly in the model-reduction process, which leads to the accuracy reduction of its controller design. In this paper, an optimal technique is selected through comparing several common model-reduction methods. Then, considering the dynamic characteristics of a high-rise building, an improved balanced truncation (BT) method is proposed for establishing its reduced-order model. The abandoned structural information, including natural frequencies, damping ratios and modal information of the original model, is reconsidered. Based on the improved reduced-order model, a new reduced-order controller is designed by a regional pole-placement method. A high-rise building with an AMD system is regarded as an example, in which the energy distribution, the control effects and the control parameters are used as the indexes to analyze the performance of the improved reduced-order controller. To verify its effectiveness, the proposed methodology is also applied to a four-storey experimental frame. The results demonstrate that the new controller has a stable control performance and a relatively short calculation time, which provides good potential for structural vibration control of high-rise buildings.