• Journal of the Korea Concrete Institute
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• v.11 no.6
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• pp.121-128
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• 1999

The SHO PATCH System Mortar is a mortar shotcreting system which uses fairly small machine and equipment, and is applied for shotcrete tunnel linings, in particular for small bore tunnels of aqueducts by the TBM(Tunnel Boring Machine) method, and for reparing tunnels suffering from spring water and deterioration. This study shows the characteristics of the new mortar shotcreting system, the SHOT PATCh System Mortar, which exhibits excellent shotcrete performance.

• Journal of Navigation and Port Research
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• v.37 no.2
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• pp.129-135
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• 2013

Recently, waste water treatment system is developed in small and middle size to get more economic advantage. Freeze concentration system has high thermodynamic efficiency and low energy consumption, can re-use purified water and cold energy obtained from ice. This study was experimentally performed to investigate pollution containment in frozen layer by cooling wall temperature, air-bubble flow methods, initial ice-lining thickness of frozen layer in NaCl aqueous solution and the representative heavy metals, Pb and Cr aqueous solution. As the result, a decrease in the cooling wall temperature bring a higher growth rate of ice front and the more solute was involved in frozen layer. The method to inject directly air-bubble into ice-liquid interface through ring shape nozzle gave high purity of ice compared to indirect method. Ice lining in 5mm thickness resulted in frozen layer with higher purity than 1mm thickness.

• The Journal of the Korean dental association
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• v.15 no.3
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• pp.199-204
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• 1977

The patient, 19 years old female, complained of protrusion of upper and lower anterior teeth. Teeth lining was good except slight crowding in lower anterior teeth. Teeth lining was good except slight crowding in lower incisors, but distocclusion in the region of right buccal segment was present. Cephalometric analysis revealed normal relation between maxilla and cranial base. The labial inclination of upper and lower anterior teeth was severe, so diagnosed as bialveolar protrusion case. She was treated by means of multibanded system under the extraction of four first bicuspids. After 1 year and 4 months. She gained good interdigitation of buccal segments and attractive facial profile because the labioversion of incisors was reduced properly.

• Proceedings of the Korean Geotechical Society Conference
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• 1993.03a
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• pp.49-58
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• 1993

Reappraisal of the design and the construction concept of the bottom drainage tunnel has been made through the seepage analysis. An appropriate design approach for this tunnel has also been proposed. It was revealed from this study that water pressures acting on the concrete lining in the bottom dralnage tunnel much depend on the permeability of the surrounding ground, the source of water supply and the discharge capacity of dralnage facilities. The full release of these water pressures by the current drainage system could not be expected if this type of tunnel is constructed in the ground including alluvial deposits having a high permeability. The necessity of a proper reinforcement of the concrete lining or a modification of its shapes corresponding to the water pressure has been suggested.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11b
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• pp.1132-1137
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• 2001

The smart foam that is first proposed by Fuller(2) is not applicable to active noise control in a duct having flow. Thus. this paper presents the ring-type smart foam as an alternative. The ring-type smart foam consists of polyurethane acoustic foam of lining shape and PVDF film embedded along the mid-surface of the foam lining. A feedforward adaptive filtered-x LMS controller is used to minimize the signal from the error microphone. To enlarge quiet sound region. two error microphones are used to update system modeling filter (SIMO method). Sound intensity control using the ring-type smart foam is also discussed

• Geomechanics and Engineering
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• v.29 no.3
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• pp.349-357
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• 2022

Abnormal climate events are occurring frequently around the world. In particular, cold waves and heavy snow lead to damage and deterioration of facilities, which can cause loss of life or property damage, such as shortening the lifespan of facilities. Therefore, it is very important to prepare an appropriate maintenance system and to establish a strategy to cope with abnormal weather conditions. In this study, laboratory freezing experiments were performed to analyze the freeze-thaw characteristics affecting the tunnel concrete lining, and heat flow analysis was carried out based on the test results. Based on these experimental and theoretical analysis results, quantitative freeze-thaw evaluation criteria for tunnel concrete linings were proposed.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1245-1252
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• 2010

Many industrialized countries are confronted with a difficulty about reuse of closed waste landfill. facilities. Especially, the demand of closed waste landfill maintenance and reuse nearby urban area has been increased, because of the shortage of usable land and extend of urban area. For the safe reuse of closed waste landfill, the most important check point is the effect of waste landfill on environment abound them. However, the non-sanitary closed waste landfill generally have no leachate lining system, therefore, the in-situ lining system such as sheet-pile, and vertical slurry wall etc. was needed to prevent the leachate outgoing from the waste landfill. In this paper present the case history of performance evaluation of vertical slurry wall by tracer tests.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.140-153
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• 2005

During the tunnel construction the major failure mode can be categorized as: tunnel failure just after the tunnel excavation without support, failure after application of shotcrete and finally failure after setting the concrete lining. The failure mode just after the tunnel excavation without support, can be further classified as : bench failure, crown failure, face failure, full face failure, failure due to weak strata and failure due to overburden. Moreover the failure after application of shotcrete is classified as heading face failure, settlement of shotcrete support, local failure of shotcrete lining and invert shotcrete. To find out the major causes of tunnel collapse, the investigation was done in case of the second phase of Seoul subway construction. The investigation results depicted that the major causes of tunnel collapse were due to the weak layer of rock/fault and sudden influx of ground water from the tunnel crown. While the investigation results of the mountain road tunnels construction have shown that the major causes of tunnel failure were inadequate analysis of tunnel face mapping results, intersection of faults and limestone cavities. In this paper some recent measurement in order to mitigate such tunnel collapse are presented

• Journal of Korea Multimedia Society
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• v.14 no.12
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• pp.1591-1600
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• 2011

The skyline of a multidimensional data set is the maximal subset whose elements are not dominated by other elements of the set. Skyline computation is considered to be very useful for a decision making system that deals with multidimensional data analyses. Recently, a great deal of interests has been shown to improve the performance of skyline computation algorithms. In order to speedup, the number of comparisons between data elements should be reduced. In this paper, we propose a filter lining scheme to accomplish such objectives. The scheme divides the multidimensional data space into angle-based partitions, and places a filter for each partition, and then connects them together in order to establish the final filter line. The filter line can be used to eliminate data, that are not part of the skyline, from the original data set in the preprocessing stage. The filter line is adaptively improved during the data scanning stage. In addition, skylines are computed for each remaining data partition, and are then merged to form the final skyline. Our scheme is an improvement of the previously reported simple preprocessing scheme using simple filters. The performance of the scheme is shown by experiments.

• Journal of Korean Tunnelling and Underground Space Association
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• v.13 no.6
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• pp.463-499
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• 2011

Control of ground water is one of the most important factors for long-term operation of tunnel because most tunnels are located under the ground water level. In case of a drainage tunnel, there is no pore water pressure on the lining when the drainage system is properly working. After long-term operation, however, residual pore water pressure can be developed on the lining due to the deterioration of the drainage system. In this study, the water pressure distribution under obstruction condition of drainage material and conduit on the tunnel is numerically investigated using the ICFEP program and compared with the current value being applied to the residual water pressure for rational application plan of residual water pressure on the tunnel linings.