• Journal of Korean Tunnelling and Underground Space Association
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• v.5 no.4
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• pp.389-400
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• 2003

In order to recommend the mechanical smoke exhaust operation mode, Subway Environmental Simulation (SES) is used to predict the airflow of the inlet and outlet tunnel for the subway station. Fire Dynamic Simulation (FDS) is used the SES's velocity boundary conditions to clarity the smoke exhaust effectiveness by the variations with mechnical ventilation system. We compared each 6 types of smoke exhaust systems for the result of smoke density and temperature distributions for 1.5m height from the subway station base in order to clarify the safety evaluation for the heat and smoke exhaust on subway fire.

• Korean Institute of Interior Design Journal
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• v.13 no.2
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• pp.159-167
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• 2004

To realize the above concepts of underground space, several underground facilities are concentrated upon and around subway stations in harmony with underground pedestrian walkways. As a result, the reduction of transit time and pedestrian distance make it easy to get to an object. In this study, underground space is considered not just as pedestrian walkways, but as space for various activities and as a positive element in connection with its circumstances. The purpose of the study is to understand underground space's elements and develop more aesthetic and efficient design of the space to give mental composure and familiarity to users. The development of underground connection space is one of the methods to improve the quality of the whole downtown area. This paper studied the general characteristics of connection space and space improvements after spot inspections and suggested several aspects useful for substantial design as essential data for development of underground connection space.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.2
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• pp.24-33
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• 2017

Domestic urban railway underground station structures, which were built in the 1970s ad 1980s, had been constructed as Cut-and-Cover construction system without seismic design. Because the trends of earthquake occurrence is constantly increasing all over the world as well as the Korean Peninsula, massive human casualties and severe properties and structures damage might be occurred in an non-retrofitted underground station during an earthquake above a certain scale. Therefore, to evaluate the retrofit effect and soil-structure interaction of seismic retrofitted underground station, a centrifugal shaking table test with enhanced stiffness on its structural main member are carried out on 1/60 scaled model using the Kobe and Northridge earthquakes. The seismic retrofitted members, which are columns, side walls, and slabs, are evaluated to comparing with existing non-retrofitted centrifuge test results Also, to simulate the scaled ground using variation of shear velocity according to site conditions such as ground depth and density, resonant column test is performed. From the test results, the relative displacement behavior between ground and structures shows comparatively similar in ground, but is increased on ground surface. The seismic retrofit effects were measured using relative displacements and moment behavior of column and side walls rather than slabs. Additionally, earthquake wave can be used to main design factor due to large structural deformation on Kobe earthquake wave than Norhridge earthquake wave.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2003.05a
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• pp.170-173
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• 2003

Because effect about environmental effect that get to human visually is absolute, ability that mural of subway interior considers relation with space is required. Also, public environment element should be designed must intend agreeableness sex by same traitor effect of quality of the material and color and can be evaluated by cultural inheritance that is powerful enemy same time. Wish to accomplish access as meaning of city environment improvement of wall of subway station or underground space etc. through Japan course South Korea's illustration regarding environment landscaping features that is designed in wall of latest domestic building subway interior in this research. Various and new reading by that study and analyze manufactured wall environment landscaping features recently that could find and was approached in variouser technique, practical use of material than single material and is expressed according to history's special quality and planning know can. Underground space can give agreeableness feel and psychological sense of security by user though expression method, material, color plan etc. consist because is having image blockade enemy. Therefore, wall environment landscaping features of underground space to be cultural value and environment Dija because diversified research that is accompanied in element is gone subway interior space of our country and underground space etc. as new culture space develop be able to must.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.4
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• pp.604-610
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• 2010

Busan subway transportation system has been established a key role in the society last 20 years. However many people are suffering from hot and humid environment at subway station and platform due to deteriorated ventilation system as well as insufficient air conditioning system in existing stations and platforms. As a result, these systems require revitalization. There is about 5400tons of low temperature underground water is generated from subway stations every day. By using this method and air washer we are trying to lower the temperature. Air washer is commonly used for removing humidity but in this experiment it will be used as air precooling. This research offers result of experiment using air washer system to lower the temperature in large spaces like subway station. The experiment result has shown when L/G was the same, at condition which water spray temperature at $18^{\circ}C$ resulting inlet and outlet temperature difference larger. Also, in the same water spray temperature conditions, larger L/G condition showed a greater temperature difference. LCC evaluation of both system were shown that air washer system of using underground water will save 53% of the initial cost than refrigeration system, and save 75% of operating cost.

• Structural Engineering and Mechanics
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• v.72 no.2
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• pp.275-291
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• 2019

In a super-large underground with "large span and high side wall", it is buried in mountains with uneven lithology, complicated geostress field and developed geological structure. These surrounding rocks are more susceptible to stability issues during the construction period. This paper takes the left bank of Baihetan hydropower station (span is 34m) as a case study example, wherein the deformation mechanism of surrounding rock appears prominent. Through analysis of geological, geophysical, construction and monitoring data, the deformation characteristics and factors are concluded. The failure mechanism, spatial distribution characteristics, and evolution mechanism are also discussed, where rock mechanics theory, $FLAC^{3D}$ numerical simulation, rock creep theory, and the theory of center point are combined. In general, huge underground cavern stability issues has arisen with respect to huge-scale and adverse geological conditions since settling these issues will have milestone significance based on the evolutionary pattern of the surrounding rock and the correlation analyses, the rational structure of the factors, and the method of nonlinear regression modeling with regard to the construction and development of hydropower engineering projects among the worldwide.

• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.99-105
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• 2022

Public attention to the indoor environment of underground subway stations, which is a representative multi-use facility, has been increasing along with the increase in indoor activities. In underground stations, fine iron oxide, which affects the health of users, is generated because of the friction between wheels and rails. Among particulate pollutant reduction technologies, plants have been considered as a non-chemical air purification method, and their effects in reducing certain chemical species have been identified in previous studies. The present study aimed to derive the total quantitative and qualitative reduction effects of a bio-filter system comprising air purifying plants, installed in an underground subway station. The experiment proceeded in two ways. First, PM(particulate matter) reduction effect by vegetation biofilter was monitored with the IAQ(indoor air quality) station. In addition, chemical speciation analysis conducted on the samples collected from the experimental and control areas where plants and irrigation using SEM-EDS(scanning electron microscopy-energy dispersive X-ray spectroscopy). This study confirmed the effect of the vegetation bio-filter system in reducing the accumulation of particulate pollutants and transition and other metals that are harmful to the human body.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.69-72
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• 1998

A study to identify the energized status of the 22.9kV underground power cable by the detection of vibration was reformed. We derived that there exists vibration at double the line frequency in live cables by electromagnetic force. The vibration can be picked up by accelerometer sensor. A prototype was tested on the underground distribution system in Chonan Station, KEPCO. The results are presented and suggest the applicability of the detecting device.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.231-235
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• 2007

As the centralization of city, underground facilities is increasing and being more important. And there were many underground facilities accidents in korea. It is very important to update and to have high quality accuracy of underground facilities maps. But the underground facilities maps are mapped and updated by each institutes. So it is difficult to verify the accuracy of the data. In this study, To analyze the accuracy of maps, Surveying of undergroud facilities for 18 GUs in Seoul is performed during 3 years using Electromegnetic Induction Method, Total Station and GPS. In conclusion, Horizontal accuracy of 6 underground facilities management institutes is 73cm(2004), 78cm(2005) and 75cm(2006).

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2002.03a
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• pp.109-116
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• 2002

Since experimental evaluation of underground RC structures considering interaction with surrounding soil medium is quite difficult to be simulated, the evaluation for the underground RC structures using an analytical method can be applied very usefully. For underground structures interacted with surrounding soils, it is important to consider path-dependent RC constitutive model, soil constitutive model, and interface model between structure and soil, simultaneously. In this paper, an elastoplastic interface model which consider thickness of interface is proposed and applied for the analysis considering the interaction. Failure mechanism of underground RC box of two story and two box subway station under seismic action is obtained and the effects of ductility of intermediate column to entire underground RC system are investigated through analysis.