• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.108-109
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• 2014

The purpose of this study is to enhance durability of solidifying mat. solidifying mat excellent mechanical properties of geotextile. multi-layer coating system is applied to the mat and the chloride ions penetration resistance, chemical resistance, accelerated carbonation test were evaluated by testing the durability. Durability test results are as follows. chloride ions penetration resistance results are coated mat is approximately 70 % lower than plain. chemical resistance test results are coated mat no discoloration. accelerated carbonation test results are coated mat is approximately 90 % lower than the plain.

• Journal of Korean Elementary Science Education
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• v.22 no.2
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• pp.156-162
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• 2003

The purpose of this study was to explore effects of 4MAT system program on the creativity, science achievement and science-related attitudesof elementary school students. 4MAT learning program is a model based on the whole brain learning including the learning styles and the cognitive specialization of left and right hemispheres. The study was conducted for 10 weeks during the 1998 second semester in H elementary school which is located in Incheon. 4MAT learning program was applied to the 5th and 6th grade students. One hundred 5th grade students and eighty three 6th grade students are selected for this study. The experimental group was taught in applying the 4MAT system, and the control group was taught by the traditional manner. The results of this study were as follows: There was a significant difference on creativity between the instruction by applying 4MAT system and the traditional instruction. In the 6th grade, there was a statistically significant difference on science achievement and science-related attitude. In the 5th grade, there was slightly increased, but statistically onsignificant. In conclusion, the instruction by applying 4MAT system was more effective in developing student's creativity than the traditional instruction in both grades.

• Journal of Environmental Science International
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• v.15 no.12
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• pp.1199-1203
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• 2006

This paper analyzes the separation efficiency of vehicles mat residual product, and caloric value, element analysis and heavy metal of separated PE & PVC mat residual product. A results of separation efficiency, fiber fraction of PE & PVC mat residual product was analyzed 71.9% and 18.6%, respectively. Caloric value of PE & PVC mat residual product was analyzed 3,894kca1/kg and 10,203kca1/kg, respectively. A results of element analysis, main component of PVC mat were carbon(33.2%) and oxygen(21.0%), and main component of PE mat fiber were carbon(75.4), hydrogen(11.3%) and oxygen(9.1%). Lead and cadmium concentration of PVC powder was detected 98.9mg/kg and 19.8mg/kg, but Lead and cadmium concentration of fiber was detected 15.7mg/kg and 6.1mg/kg.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.249-252
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• 2005

Microphytobenthos bloom from late January to early March in Korean tidal flats. KOMPSAT-2 will provide multi-spectral images with a spatial resolution of 4 m comparable with IKONOS. Using IKONOS and Landsat data, algal mat detection was tested in the Saemangeum area~ Micro-benthic diatoms are abundant and a major primary product in the tidal flats. A linear spectral unmixing (LSU) method was applied to the test data. LSU was effective to detect algal mat and the classified algal mat fraction well correlated with NDVI image. Fine grained upper tidal flats are generally known to be the best environment for algal mat. Algal mat thriving in coarse grained lower tidal flats as well as upper tidal flats were reported in this study. A high resolution multi-spectral sensor in KOMPSAT-2 will provide useful data for long-term monitoring of microphytobenthos in tidal flats.

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.43.3-43
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• 1998

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.4
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• pp.12-22
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• 2005

The purpose of this study is to select suitable planting base for the mat-type rooftop greening in order to popularize rooftop greening system easily. The experiment was conducted from 2004 June to 2005 May under several conditions; 4 soil depths under mats(2cm, 5cm, 10cm, 15cm), two soil mixtures(natural soil 80%+leaf mold 20%, artificial soil) and two light conditions(full sun place, 20% shaded place). In this experiment, 3 types of mats were used ; the herbaceous plants mat(11 plants inclusive of Lotus corniculatus L., Silene armeria L.), the lawn mat with Festica arundinacea and Sedum mat with Sedum kamtschaticum, Sedum sarmentosum, Sedum oryzifolium, Sedum middendorffianum. The result is as follows; in the mat-type rooftop greening, the herbaceous plants mat, lawn mat and sedum mat are the similar number of plant and effect of greening on soil depth 2cm, 5cm and 10cm, 15cm. So suitable soil depth of rooftop greening is 10cm for the load and economical factor. Thus the mat-type rooftop greening possible planting base depth of all 13cm as soil depth 10cm and mat depth 3cm. As soil mixtures, the number and growth of plants were better mat and 'natural soil 80% +leaf mold 20%' than mat and artificial soil. In herbaceous plants mat, Silene armeria L., Dianthus chinensis, Centaurea cyanus L., Lotus corniculatus L. are survival in full sun place and Silene armeria L., Dianthus chinensis, Centaurea cyanus L. are survival in 20% shaded place. In conclusion, selection of suitable soil mixtures and plants is possible extensive management rooftop greening with effect of continuous greening. The mat-type rooftop greening are lightweight and simple preparation without management and can popularize readily.

• ETRI Journal
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• v.32 no.1
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• pp.112-119
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• 2010

We present a useful design for a free access mat which supports two frequency bands of 2.4 GHz and 5 GHz. The free access mat is a sheet-shaped waveguide which consists of a tightly coupled double-layered microstrip resonator array. It provides easy access for devices in short-range wireless communications. Interference is a common problem with conventional applications which use free space transmission. Our proposed wireless access system uses a subsidiary waveguide, the free access mat. Wireless devices are proximately coupled to the free access mat through which the coupled electromagnetic (EM) wave transmits. The arrival domain of the EM wave of an application is therefore limited to an area close to the free access mat. Wireless devices can be coupled to the free access mat at an arbitrary position without contact. We previously presented a free access mat for a single frequency band. This paper presents a free access mat for the two frequency bands of 2.4 GHz and 5 GHz. The free access mat uses a ring patch resonator array which is easily excited by typical antennas and is resistant to interference. These characteristics are demonstrated by numerical simulation and confirmed by experiment.

• Journal of the Earthquake Engineering Society of Korea
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• v.25 no.4
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• pp.169-177
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• 2021

In this paper, horizontal seismic responses of a structure built on a sunken mat foundation were compared with those built on a solid embedded mat foundation to investigate the effect of a sunken mat foundation on the horizontal response of a structure. Seismic analyses of a structure laid on the embedded mat foundation were performed by utilizing a pseudo-3D finite element software of P3DASS. Three bedrock earthquake records downloaded from the Pacific Earthquake Engineering Research Center database were scaled to reproduce weak-moderate earthquakes. Weak, medium, and stiff soil layers were considered for the seismic analyses of the structure-foundation-soil system. Parametric studies were performed for foundation radius, foundation embedment depth, and shear wave velocity of a soil layer to investigate their effect on the seismic response spectrum. The study result showed that the design spectrum of a structure built on a sunken mat foundation was similar to that with a solid embedded mat foundation showing a slight difference due to almost the same seismic base motion beneath both embedded foundations.

• Journal of Ocean Engineering and Technology
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• v.25 no.2
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• pp.47-54
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• 2011

A piled raft foundation is one of the systems used to reduce the settlement of structures. However, the general design method for a piled raft foundation system assumes that the piles only support external loads, which exclude the bearing capacity of the raft itself. In this study, an experimental model test was performed to evaluate the raft capacity for the external load on the sand. Additionally, a part of the sandy ground under the raft was replaced with a gravel mat to reinforce the piled raft foundation system and increase the bearing capacity. Then, parametric studies of the reinforced ground were performed to determine the displacement and load-sharing ratio of the piled raft foundation system.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.5
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• pp.135-142
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• 1995

This paper presents the effect of the component performance for mat supported monolithic cordierite ceramic underflow catalytic converters to meet the new stringent durability requirements of the world's. These objectives are met by a conceptional system approach of mat mounting material with stainless steel can(shall), and heatshield(cover), which are related to the mat erosion, a main failure pattern of the mat supported monolithic ceramic catalytic converters. In this paper we study the individual component behavior of mat erosion problem, After studying, we obtain the characterics of the component performance for automotive catalytic converters and the overall understanding of design considerations in catalytic converters.