• Tunnel and Underground Space
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• v.11 no.1
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• pp.64-71
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• 2001

The purpose of this study is to develop rail rockfall and landslide information system to manage spatial database using GIS. For this, a spatial database containing information such as railroad, map, topographic analysis, meteorological data, and rockfall has been constructed for 2.5 km or 5 km buffer zone from the Kyungchun, Youngdong, Jungang, Taebak and Jungsun Rairoad where risk of landslide occurrence potential is high. For management of the spatial database, railroad rockfall and landslide information system has been developed. The information system consists of view, table, chart, layout and project environment. The functions provided in the system are data conversion, editing, labeling, zoom in and out, map making, graphic editing, text DB management, charting, on-line help as well as input, retrieve and output of spatial database. The system was developed using ArcView script language Avenue, and consisted of pull-down menus and icons for easy use. The spatial database and the information system can be used to rockfall and landslide management and analysis near the railroad as basic data and tool.

• Journal of Korean Association for Spatial Structures
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• v.15 no.1
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• pp.65-73
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• 2015

This paper presents the structural model verification process of whole wind turbine blade including blade model which proposed in Part1 paper. The National Renewable Energy Laboratory (NREL) Phase VI wind turbine which the wind tunnel and structural test data has publicly available is used for the study. In the Part1 of this paper, the processes of structural model development and verification process of blade only are introduced. The whole wind turbine composed by blade, rotor, nacelle and tower. Even though NREL has reported the measured values, the material properties of blade and machinery parts are not clear but should be tested. Compared with the other parts, the tower which made by steel pipe is rather simple. Since it does not need any considerations. By the help of simple eigen-value analysis, the accuracy of structural stiffness and mass value of whole wind turbine system was verified by comparing with NREL's reported value. NREL has reported the natural frequency of blade, whole turbine, turbine without blade and tower only models. According to the comparative studies, the proposed material and mass properties are within acceptable range, but need to be discussing in future studies, because our material properties of blade does not match with NREL's measured values.

• Journal of the Korean Arthroscopy Society
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• v.4 no.1
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• pp.1-6
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• 2000

Purpose : The purpose of this study was to compare the results of ACL reconstruction using bone-patellar tendon-bone to hamstring. Materials and Methods : Thirty-two ACL reconstructions with autogenous BPTB and eighteen reconstructions with hamstring were compared in terms of functional outcome, stability and tunnel expansion. Results : The functional score of BPTB group was higher than hamstring group in OAK(Orthopadishe Arbeitsguppe Knie) and IKDC(International Knee Documentation Committee) system. In BPTB group, OAK scores were 71.6$({\pm}10.0)$ preoperatively and 88.5$({\pm}7.9)$ finally. In hamstring group, OAK scores were 73.9$({\pm}11.5)$ and 82.5$({\pm}12.9)$ respectively. There was no difference in stability checked by either $KT-1000^{TM}$ or stress view. Anterior tibial translation measured by $KT-1000^{TM}$ were 2.4$({\pm}1.8)$mm in BPTB and 2.3$({\pm}2.4)$mm in hamstring group. Anterior tibial translation in stress view were 2.8$({\pm}3.4)$mm in BPTB and 2.8$({\pm}2.5)$mm in hamstring group. There was no difference in tibial tunnel expansion but femoral tunnel was more enlarged in hamstring group than BPTB (P=0.03). Conclusion : As there was no difference in stability between two groups, it seems prudent to select either graft defend on such factors as anterior knee pain, skeletal maturity and cosmetic concern. Tunnel expansion seems not to affect stability, but further study is needed to confirm that decrease of which might improve stability.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.167-174
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• 2001

Reflection method using ultrasonic source has been attempted to obtain the information about tunnel lining structures composed of lining, shotcrete, water barrier and voids at the back of lining. In this work, two different types of sources, i.e. single-pulse source and sweep source, can be used. Single-pulse source with short time duration has the frequency content whose amplitudes tend to be concentrated around the dominant frequency, whereas sweep source with long time duration denotes a flat distribution of relatively larger amplitude over a broad frequency band, although the peak to peak amplitude of single-pulse source wavelet is equivalent to that of sweep source one. In traditional seismic application, a single-pulse source(weight drop, dynamite) is typically used. However, to investigate the fine structure, as it is the case in the tunnel lining structure, the sweep wavelet can be also a desirable source waveform primarily due to the higher energy over a broad frequency band. For the investigation purposes of sweep source, a physical modeling is a useful tool, especially to study problems of wave propagation in the fine layered media. The main purpose of this work was using a physical modeling technique to explore the applicability of sweep source to the delineation of inner layer boundaries. To this end, a two-dimensional physical model analogous to the lining structure was built and a special ultrasonic sweep source was devised. The measurements were carried out in the sweep frequency range 10 ∼ 60 KHz, as peformed in the regular reflection survey(e.g. roll-along technique). The measured data were further rearranged with a proper software (cross-correlation). The resulting seismograms(raw data) showed quitely similar features to those from a single-pulse source, in which high frequency content of reflection events could be considerably emphasized, as expected. The data were further processed by using a regular data processing system "FOCUS" and the results(stack section) were well associated with the known model structure. In this context, it is worthy to note that in view of measuring condition the sweep source would be applied to benefit the penetration of high frequency energy into the media and to enhance the resolution of reflection events.

• Journal of computational fluids engineering
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• v.7 no.3
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• pp.27-34
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• 2002

When caught in a fire inside a building or a tunnel the generated smoke is the main cause of the bad visibility, which makes it difficult for a person to find escape route. Therefore of the fire simulation it is required to visualize the simulated results of smoke realistically form a viewpoint of a person caught in a fire. In the present study, developed is a CFD post-processor which can visualize the object through smoke from the results of CFD fire simulation. Examples of some applications of the program are shown in the paper.

• Nuclear Engineering and Technology
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• v.31 no.6
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• pp.83-100
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• 1999

As disposal packaging concepts of spent fuels generated from the domestic NPP, two types, one is to package PWR and CANDU spent fuels in different containers and the other is to package them together, were proposed. The configuration of the containers and the layout of underground repository, such as the container spacing and the deposition tunnel spacing, were developed. The layout of underground repository satisfies the thermal constraint of the bentonite buffer surrounding disposal container, which should be lower than $100^{\circ}C$ in order to keep the physical and chemical properties of bentonite From the spent fuel packaging concepts and container emplacement methods, seven options were developed. With a typical pair-wise comparison methods, AHP, the most promising disposal concept was selected based on the technology Point of view.

• Wind and Structures
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• v.6 no.3
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• pp.221-248
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• 2003

The design of high-rise building is often influenced by wind-induced motions such as accelerations and lateral deflections. Consequently, the building's structural stiffness and dynamic (vibration periods and damping) properties become important parameters in the determination of such motions. The approximate methods and empirical expressions used to quantify these parameters at the design phase tend to yield values significantly different from each other. In view of this, there is a need to examine how actual buildings in the field respond to dynamic wind loading in order to ascertain a more realistic model for the dynamic behavior of buildings. This paper describes the findings from full-scale measurements of the wind-induced response of typical high-rise buildings in Singapore, and recommends an empirical forecast model for periods of vibration of typical buildings in Singapore, an appropriate computer model for determining the periods of vibration, and appropriate expressions which relate the wind speed to accelerations in buildings based on wind tunnel force balance model test and field results.

• Tunnel and Underground Space
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• v.2 no.2
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• pp.190-198
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• 1992

This study is to summarize the contents for the investigation and design of the construction for oil storage. Since underground caverns are large scale, in their construction one should consider the mechanical stability of caverns and the economic view of construction. On the basis of them, cavern's section and layout were determined and water curtains were designed to maintain hydraulic equilibrium so that gases were sealed tightly. Also the supporting criterial for rock bolt and stotcrete were determined by means of the classification of rock masses and the results of finite element method. The criteria of grouting reinforcement were presented according to the results of injection test in the pilot holes of working face.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2001.02a
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• pp.108-111
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• 2001

This paper presents the possible application of a HTS superconducting power cable for transmitting electric power in metropolitan areas, reflecting its important distinction such as compactness for installation in underground ducts and considerably economical efficiency comparable to present underground cables. In this paper, we investigated characteristic and market scale compact HTS transmission cable which is possible to install in underground ducts. And reviewed its economical efficiency comparing to present existed CV cable from point of view such as cost for cable construction and duct or tunnel installation.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.163-168
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• 2005

In case of rolling stock, SEMS is generally applied in the advanced countries, but is start stage in our country. SEMS is defined the system engineering management system in order to achieve the optimized train performance among the several client requirements aspect of technical engineering management during the design life cycle. And the fire engineering activities in hong kong EMU project are introduced aspect of SEMS in this paper. The fire engineering at rolling stock in view of SEMS controls to apply the satisfied interior material by the fire safety standards (regulation of the commute urban subway safety guideline by the MOCT, BS 6853, NFPA 130, NF F 16-101) and to minimize the fire load in order that passengers egress safe from the fired rolling stock. The rolling stock in the advanced countries is designed to stand for 15-20 minutes in considering the rolling stock to be fired in tunnel. For passenger fire safety, the passenger evacuation provision and progress is set up.