• Proceedings of the Korea Air Pollution Research Association Conference
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• 2009.10a
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• pp.358-359
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• 2009

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1213-1217
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• 2007

In this paper some sets of numerical simulations for passenger evacuation in a fire occurred underground station under various smoke-control ventilation modes. Passenger evacuation flows are calculated by EXODUS program. As input data for EXODUS program, distributions of temparature, smoke and toxicity due to fire in the underground station are evaluated by Fire Dyanamic Simulator (FDS).

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2007.04a
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• pp.345-348
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• 2007

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.505-512
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• 1998

지하철과 같은 지하구조물 설계시 기존 구조물 지하를 관통하는 경우가 있다. 본 논문은 기존 역사의 바닥슬래브 밑에 새로운 지하철용 박스 구조물 상부 슬래브가 위치하게 되는 특별한 경우의 굴착 방법을 제시하고 제시된 굴착방법이 상부 구조물에 어떤 영향을 미치는지를 FLAC을 이용하여 검토해 본 것이다. 기존 구조물이 위치하고 있는 지반이 경암인 경우 발파가 주의 깊게 설계되고 시행된다면 발파로 인한 상부 구조의 진동 영향은 충분히 제어할 수 있는 수준으로 예상되었다.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1809-1815
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• 2008

This experiment simulated the fire driven flow of an underground station through parallel processing method. Fire analysis program FDS(Fire Dynamics Simulation), using LES(Large Eddy Simulation), has been used and a 6-node parallel cluster, each node with 3.0Ghz_2set installed, has been used for parallel computation. Simulation model was based on the Kwangju-geumnan subway station. Underground station, and the total time for simulation was set at 600s. First, the whole underground passage was divided to 1-Mesh and 8-Mesh in order to compare the parallel computation of a single CPU and Multi-CPU. With matrix numbers($15{\times}10^6$) more than what a single CPU can handle, fire driven flow from the center of the platform and the subway itself was analyzed. As a result, there seemed to be almost no difference between the single CPU's result and the Multi-CPU's ones. $3{\times}10^6$ grid point one employed to test the computing time with 2CPU and 7CPU computation were computable two times and fire times faster than 1CPU respectively. In this study it was confirmed that CPU could be overcome by using parallel computation.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2013.11a
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• pp.83-84
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• 2013

본 연구는 국내 현실적인 기준 반영을 위하여 인구 유동에 있어 출퇴근 이용자가 집중되고 상업활동이 복합된 지하상가의 유동인구를 측정하여 재실자 밀도를 분석하였다. 실측 결과, 지하역사의 연결부분은 퇴근 시간을 기점으로 하여 인원이 편중되었으며 상업시설은 11시, 14시, 17시 등 다양한 시간에 이용자가 편중되는 특성을 나타냈다. 아울러 재실자 밀도는 1.52인/$m^2$로 현재 국내 기준과는 달리 다소 높은 분포를 보여주고 있다.

• Journal of Intelligence and Information Systems
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• v.28 no.1
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• pp.329-352
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• 2022

It is reported that particulate matter(PM) penetrates the lungs and blood vessels and causes various heart diseases and respiratory diseases such as lung cancer. The subway is a means of transportation used by an average of 10 million people a day, and although it is important to create a clean and comfortable environment, the level of particulate matter pollution is shown to be high. It is because the subways run through an underground tunnel and the particulate matter trapped in the tunnel moves to the underground station due to the train wind. The Ministry of Environment and the Seoul Metropolitan Government are making various efforts to reduce PM concentration by establishing measures to improve air quality at underground stations. The smart air quality management system is a system that manages air quality in advance by collecting air quality data, analyzing and predicting the PM concentration. The prediction model of the PM concentration is an important component of this system. Various studies on time series data prediction are being conducted, but in relation to the PM prediction in subway stations, it is limited to statistical or recurrent neural network-based deep learning model researches. Therefore, in this study, we propose four transformer-based models including spatiotemporal transformers. As a result of performing PM concentration prediction experiments in the waiting rooms of subway stations in Seoul, it was confirmed that the performance of the transformer-based models was superior to that of the existing ARIMA, LSTM, and Seq2Seq models. Among the transformer-based models, the performance of the spatiotemporal transformers was the best. The smart air quality management system operated through data-based prediction becomes more effective and energy efficient as the accuracy of PM prediction improves. The results of this study are expected to contribute to the efficient operation of the smart air quality management system.

• Journal of the Korean Society for Railway
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• v.17 no.5
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• pp.328-335
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• 2014

Numerical prediction methods were applied to investigate the turbulent air currents and air-conditioning efficiency in an underground subway station, and the results compared to experimental data. The Shin-gumho Station($8^{th}$ floor underground and 43.6m in depth) in Seoul was selected for the analysis. The entire station was covered for simulation and the ventilation mode was ordinary. The ventilation diffusers were modeled as 95 square shapes of $0.6m{\times}0.6m$ in the lobby and as 222 square shapes in the platform. Cooling air of $47,316m^3/h$ was supplied and the returned air of $33,980m^3/h$ is exhausted in the lobby and the cooling air of $33,968m^3/h$ is supplied and the returned air of $76,190m^3/h$ was exhausted in the platform which is the same as the experimental data. The cases of the screen-door-closed and open were respectively investigated. A total of 7.5million grids were generated and the whole domain divided into 22 blocks for MPI efficiency of calculation. Large eddy simulation (LES) was applied to solve the momentum and energy equation.

• Journal of Korea Water Resources Association
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• v.56 no.10
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• pp.667-678
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• 2023

In this study, quasi-3D inundation flow simulations were conducted for a simplified subway station configuration. The effects of variations in rainwater inflow locations and discharge were investigated, analyzing the resulting inundation flow patterns and flood risk. The inundation simulation results calculated the incipient velocities for slipping and toppling accidents to assess pedestrian safety. The results indicated that velocities exceeding the incipient velocity for slipping accidents mainly occurred on the flooded staircase. Meanwhile, velocities surpassing the incipient toppling accidents were observed around the staircase and the corridor near the staircase leading to B2F. This observation is consistent with the results from the specific force distribution analysis. To provide detailed flood risk assessments, the Flood Hazard Degree (FD) was applied with four levels of criteria, along with the Flood Intensity Factor (FIF). The results demonstrated that FD identified a broader area at risk of flood-induced consequences compared to FIF. When comparing the different inundation risk assessment methods, the specific force method tended to overestimate the risk area, whereas FIF tended to underestimate it. Furthermore, among all assessment methods, the influence of rainwater discharge was found to have a more dominant effect on flood risk assessment compared to the number of rainwater inflow locations. Additionally, the direction of inundation flow influenced the assessed risk, with collision-induced flow patterns leading to higher flood risk than those with identical flow directions.

• Journal of the Speleological Society of Korea
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• no.53
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• pp.15-24
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• 1998

여가 및 레저에 대한 의식구조의 변화와 가족 중심의 여가활동의 비중이 증가하면서 자연학습장으로서, 지구과학 전시관으로서의 역할을 하고 있는 동굴이 이동을 전제로 한 가족 단위 관광객들의 관광 대상지로서 주목받고 있다. 이에 본 연구에서는 관광자원으로서의 동굴의 특성을 살펴보고, 그 중에서도 개발 역사가 오랜 성류굴의 관광적 특성을 살펴보았다. 그 결과는 다음과 같다. 동굴은 지형 ·지질작용과 관계가 깊은 자원이지만 지하의 신비적 경관이 관광자원으로 활용되고, 그 구조의 특성에 따라 산업적 ·군사적 또는 학술적 연구의 이용에 크게 기여하는 등 다기능적 복합성을 띠고 있기 때문에 본 연구에서는 동굴을 ‘복합 관광자원’이라 분류한다. 이런 동굴 중에서 성류굴은 오랜 역사를 지닌 관광자원으로서 구전 전설의 주인공이라는 ‘문화 · 역사적인 특성’, 다양한 볼거리를 제공하는 ‘지형적인 특성’, 도로와 철도를 이용한 ‘교통접근성’ 등의 관광적 특성을 지니고 있다.