• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.190-195
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• 2013

In this study, the response of 22 soybean cultivar sprouts to flooding stress was investigated. After sprouts were subjected to flooding stress for 10 days at the V4-V5 growth stages, their dry weights were compared. All plants were kept in a greenhouse under natural light conditions, an average daytime temperature of $35.6{\pm}5.3^{\circ}C$ and an average nighttime temperature of $18.2{\pm}1.7^{\circ}C$. Soybeans were grown in a concrete bed filled with silt loam soil. Subjecting plants to flooding stress resulted in a large reduction in plant dry weight, plant height, number of nodes, and number of leaves. Cultivars differed significantly in their responses to flooding stress, as indicated by these characteristics (p<0.05). Soybean cultivars were classified into three groups based on their degree of flood tolerance: strong, moderate, and weak. Hannamkong, Namhaekong, Sobaegnamulkong, and Sorogkong had strong tolerance for flood conditions. Tawonkong, Pureunkong, Eunhakong, Myeongjunamulkong, Doremikong, Saebyeolkong, Paldokong, Sowonkong, Pungsannamulkong, Dagikong, Dachaekong, and Anpyeongkong had weak tolerance for flood conditions.

• Journal of the Korean Society of Safety
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• v.30 no.2
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• pp.27-34
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• 2015

Nowadays, remodeling cases for some apartment like Hyundai through the support of government are reported. Conventionally, balcony and aisle are extended for additional private area or balcony which is supported by new frame is extended. In extension work at site, dowel bar is conventionally inserted in old concrete slab for connection with old and new slab, however, an examination for structural safety is rarely performed prior to construction, if ever, vertical load is only considered for structural analysis. When conventionally connected structures are exposed to earthquake, the old and new structures have individual earthquake behavior with different mode, which may lead the elimination of resistance to earthquake in new structures. As of this reason, new detailing connection system which can have light weight and sufficient ductility performance is developed for application to domestic extension works. Additionally, user manual and specification are also developed for fertilization of application for the developed technology.

• Journal of the Korean Society of Safety
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• v.29 no.6
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• pp.81-86
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• 2014

Composite materials have high specific stiffness, specific strength than existing concrete or steel materials. It has superior dynamic properties when utilizing advantages of material such as Non-corrosive, light weight, non-conducting and it has superior mold ability which can make variable shapes. Thus, in the construction, for using composite materials as construction materials, the study carried out static strength of fiber right angle direction and fatigue performance of FRP deck member. The study is going to deduct S-N curve by analyzing the results comparatively and estimate long-term durability. From now on, the study is going to provide interpretation of FRP member and basic data of design basis, furthermore providing foundation technique of composite materials' application of structural frame is the goal of this study.

• Journal of the Korean Society for Advanced Composite Structures
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• v.6 no.3
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• pp.1-7
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• 2015

Compared with conventional construction materials such as steel and concrete, the advanced composite materials are corrosion-free, light-weight, and when used as construction materials, the construction period can be made less than one-tenth needed for conventional materials. However, because of the difficult theories and formulas, the ordinary construction engineers have difficulties in understanding and calculating formulas needed in construction. In this paper, calculation of the stiffnesses of the advanced composite laminated plates and compared with the result of stiffnesses.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.280-284
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• 2005

Existing construction materials such as concrete and steel have chronic problems; deterioration and corrosion. Owing to its special features of light weight ‘ high durability, anti-corrosion, composite material used in civil infrastructure can not only solve fundamental problems of deterioration and corrosion, but also reduce both construction and maintenance cost significantly. After the fabrication of deck panel with snap-fit connection by pultrusion through composite design according to stacking sequence of composite laminates and structural analysis, performance of decks will be verified and evaluated by structural tests.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.647-654
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• 2006

In orthotropic steel decks, it is likely to have defects due to fatigue damages because most of structural joints(the connection of longitudinal rib and transverse rib, the connection of deck plate and longitudinal rib) are connected by welds. However. orthotropic steel decks have many advantages. such as light weight and reduction of construction time. in comparison with concrete decks. Therefore. they are mostly used in long-span bridges and urban highway bridges. This study consists of the cause identication of fatigue damage and the suggestion of rational thickness on deck plate about the connection of deck plate and longitudinal rib. The results are as follows: fatigue damage cause at the connection of deck plate and longitudinal rib is local deformation in deck plate. And, rational thickness of deck plate is 16mm thickness.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.686-691
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• 2005

State of the art and current issues related with the RC and PSC structure system for the magnetic levitation train were investigated. The German and China magnetic levitation train adopted a new kind of a structure to enable high-speed transportation, which allows the use of the space over a ground. The loading from magnetic levitation trains is light-weight compared with a regular train due to load distribution to a supporting structure. Therefore, the magnetic levitation train is considered an economical and efficient transportation system, and is also an environmentally-sustainable structure. In this paper, the structural design and construction technology specific to a magnetic levitation train were discussed, and structural considerations related with an actual operation of the train were pointed out. In addition, the future research area of a magnetic levitation train was proposed

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.240-248
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• 2004

Recently, the customer's demands for automotive steel sheet have been diversified and sterned more. Therefore, as the tendency of auto industry light-weight, one among these requirements is the trend for high strength together with the thinness of automotive steel sheet. Because Mn added essentially in producing high strength steel sheet is bonded strongly with oxygen, the Fine oxidation layer was created at the welding face after the flash butt welding operated in entry section of pickling line. Thereby it was caused the crack or breakage of welding part in process of cold rolling. At this research, in order to protect the contact Mn with oxygen in atomosphere it was considered to fire oxygen with LNG and the related researches have been gone forward with the find out concrete and to apply them to operation.

• Computers and Concrete
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• v.26 no.5
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• pp.411-420
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• 2020

Deep Convolution neural network (DCNN) has been widely used in the healthy maintenance of civil infrastructure. Using DCNN to improve crack detection performance has attracted many researchers' attention. In this paper, a light-weight spatial attention network module is proposed to strengthen the representation capability of ResNet and improve the crack detection performance. It utilizes attention mechanism to strengthen the interested objects in global receptive field of ResNet convolution layers. Global average spatial information over all channels are used to construct an attention scalar. The scalar is combined with adaptive weighted sigmoid function to activate the output of each channel's feature maps. Salient objects in feature maps are refined by the attention scalar. The proposed spatial attention module is stacked in ResNet50 to detect crack. Experiments results show that the proposed module can got significant performance improvement in crack detection.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.402-406
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• 2006

The physical and chemical characteristics of ALC were analyzed and showed 2.2 of specific gravity and 9.05 of pH. The results of leaching tests with standard method for soil and waste indicated heavy metals(Cu, Cd, Pb, $Cr^{6+}$) were under maximum concentration level. The anaerobic digestion sludge was attached in the surface of ALC within 90 hours. As the results of batch test, pH of the ALC and Bio-ALC were decreased from initial pH of ALC to 8.7 and 7.8 respectively Also, the concentration of heavy metals was rapidly eliminated in the solution with the batch test. The result of column experiment indicates that the removal efficiency of ALC was showed 66% of T-P, 60% of T-N, and 67% of CODcr. Also, removal efficiency of Bio-ALC was slightly higher than that of ALC in T-N (64%) and CODcr (74%).