• Tunnel and Underground Space
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• v.19 no.6
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• pp.567-582
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• 2009

The world's largest nucleon decay experiment facility is constructed at a depth of approximately 1,000meters, in the Kamioka mine, Japan. Because of the character as a large cavern in deep underground, in-situ stress measurements were conducted to provide basic information for design of the cavern. Three overcoring methods were used: 8-element embedding gauges developed by Japanese Central Research Institute of Electric Power Industry, hemispherical ended borehole technique with eight strain cross-gauges, and Hollow Inclusion Cell with 12 strain gauges. The principle stresses were not perfectly similar in each measurement. The average values of the 6 stress element were used to provide the direction and the magnitude of three principle stress.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.10a
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• pp.317-322
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• 2003

최근 국내에서는 여의도 공동구, 종로 공동구 화재 등과 같이 지중 송전계통인 지하 공동구 및 전력구 화재의 발생으로 인하여 경제적, 사회적 손실이 커지고 있다. 공동구 화재가 가져오는 파급효과는 국가 기간시설의 마비 등과 같은 손실을 최소화하기 위한 화재 원인 분석 및 화재 예방과 방재대책 마련이 시급히 요구된다.(중략)

• Tunnel and Underground Space
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• v.20 no.6
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• pp.434-445
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• 2010

Underground compressed air energy storage (CAES) system in a lined rock cavern is considered one of the promising large-scale energy storage technologies. In this study, permeabilities of concrete lining block and its construction joint, which are the major components of an air tightness system of the undeground CAES, were measured from a model experiment. From the experiment, it was found that intrinsic permeability of construction joint was larger than that of concrete block by the order scale of $10^1{\sim}10^4$, so that it would be very important to control the quality of construction joints in-situ in order to secure air tightness of storage system. And the permeability of construction joint could be decreased as low as that of the concrete block by pasting an acryl-type adhesive on bonding surfaces. Higher degrees of water saturation of the concrete block resulted in the lower permeability, which is more preferable in the viewpoint of air tightness of storage cavern.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2011.09a
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• pp.269-273
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• 2011

• Journal of the Korean Society of Safety
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• v.25 no.6
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• pp.203-209
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• 2010

A compact ANSI/EIA 709.1 protocol analyzer system suited for maintenance of LonWorks network for safety management of underground facilities was developed and tested. The hardware is based on the TMS320LF2406A embedded system, and the software was designed using Visual C++6.0 under Windows XP environment. Connected to the LonWorks network the developed protocol analyzer decodes the raw packets and pass them to the master PC through USB port. Then on the PC the packets are processed and analyzed in various aspects and the key features that are essential to the maintenance of LonWorks network installed at underground facilities are displayed in a user-friendly format. Performance of the developed protocol analyzer was evaluated through a series of experiments, by measuring the speed of packet analysis and the error rate. The protocol analyzer proved to work reliably even under the increased bandwidth. However, more comprehensive tests under various underground environmental conditions are desired.

• Explosives and Blasting
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• v.36 no.3
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• pp.29-38
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• 2018

With the recent industrial developments and economic development nationally, there has been a rapidly increasing demand for the use of underground space as locations for establishing social infrastructure and various convenience facilities. In this study, a mist-control system was developed to reduce the generation of dust in underground blasting. To enhance the dust-reduction effect, a guiding device was developed which is capable of adjusting the direction of the spray toward's the blasting face of mine or tunnel. A numerical analysis was performed by using the AUTODYN software, and results were compared with those published in basic experiments. To verify the mist-diffusion effect according to the position of explosives in a water bag, numerical analyses were conducted for the following cases: Explosives were set in the middle, and in the bottom of the water bag. The optimum condition was external detonation and center charge. The mist particle size from the result was suitable for the reduction of dust after blasting in underground mine and tunnel.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.1B
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• pp.125-135
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• 2010

Recently, the problem of global warming has issued seriously, so Green IT(Information Technology) using RFID/USN is concerned in order to solve environmental problems. In this paper, we implemented that public area like an underground parking lot could reduce unnecessary energy consumption used by lighting control system based on Ubiquitous Sensor Networks. The lighting control system for underground parking lot is comprised of intersection nodes for watching cars enter and leave, and light node for controlling light. It applies the routing protocol based on hierarchical cluster, hierarchical addressing method, and probability filtering method for the specific place like an underground parking lot. The result after experiments shows that the lighting control system could decrease electrical energy consumption to around 61.7%.

• Journal of Korea Water Resources Association
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• v.52 no.3
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• pp.227-234
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• 2019

The vulnerability of urban disasters is increased with the rapid urbanization and industrialization, and the extreme rainfall event is increased due to the global climate change. Urban inundation is also increased due to the extreme rainfall event beyond the capacity limit of facility for the damage prevention. The underground detention vault and the underground drain tunnel are rapidly being utilized to prevent urban inundation. Therefore, the hydraulic review and design analysis of the inlet of the underground facility are important. In this study, the water level of the approach flow according to the inflow discharge is measured and the flow characteristic of the inlet (tangential and spiral) is analyzed. For the spiral inlet, the multi-stage is introduced at the bottom of the inlet to improve the inducing vortex flow at low discharge conditions. In case of the tangential inlet, the discharging efficiency is decreased rapidly with hydraulic jump in the high flow discharge. The rising ratio of the water level in the multi-stage spiral inlet is higher than the tangential inlet, but the stable discharging efficiency is maintained at low and high discharge conditions. And the empirical formula of water level-flow discharge is derived in order to utilize inlets used in this study.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.20 no.2
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• pp.171-181
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• 2002

As the result of the analysis of the underground utility map made before, we could have divided the kind of errors into the two types, position error of geometric data and attribute error and knew the fact that mainly position error is derived from the process of detecting and surveying the underground utility, and attribute is inputting data. In this study we showed the way improving accuracy in detecting and surveying underground utility by field test, and the way to reduce attribute error by process refinement.

• Journal of the Mineralogical Society of Korea
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• v.19 no.4 s.50
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• pp.239-246
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• 2006

KAERI Underground Research Tunnel (KURT) was recently constructed through the site investigation from the yea. of 2003 at KAERI site, Dukjin-dong, Yuseong-gu, Daejeon city. The geo-logic setting of the site has been slightly metamorphosed. There are small fractures developed in the rock and several kinds of secondary filling minerals exist in the fractures. We examined mineralogical characteristics of fracture-filling calcite, which is not only largely distributed, but also can significantly affect the radionuclides migration. The calcite is found along fractures like other secondary minerals, forming thick veins in part. Most calcite-filled fractures contain quartz, iron oxides, and dolomite as minor minerals. The calcite crystals show an characteristic appearance with an uniformly oriented growth, coated with goethite on the edge and the etch-pit sites of their surface. Some calcite crystals have been newly formed by the precipitation of elements dissolved from the tunnel shotcrete wall, and their morphology changed according to the chemistry and flow of groundwater. The calcite can modify the groundwater chemistry and significantly affect the sorption behavior of radionuclides. The characteristic crystal structure and surface morphology of the calcite examined in the KURT site will be used as important basic data for the radionuclide migration experiment in the future.