• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.653-658
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• 1999

Bond between reinforcing bars and the surrounding concrete is supposed to safely transfer load in the design process of reinforced concrete structures. Bond failure of reinforcing bars generally take place by splitting of concrete cover as bond force between concrete and reinforcing bars exceeds the resistance by the confinement of the concrete cover and transverse reinforcement. Confinement, concrete cover and transverse reinforcement, on bond are the key factor of current provision to determine development length of reinforcing bars to concrete. In this study, previous available data are analyzed with respect to the current provisions for development and splice of reinforcement. From this study, the new provision for the design are proposed, which will be efficient and effective with some specific limit value.

• ETRI Journal
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• v.6 no.2
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• pp.15-17
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• 1984

A long-wavelength ($1. 3\mum$) multimode fiber-optic transmission system has been developed and the field trial system has been installed over 17.3km distance in Daejeon Area by KETRI. The 45Mb/s and 90Mb/s system operate with BER $10^-9$over 17.3km distance, and they successfully operate on the route of 34. 6km length when the fiber cable is simply connected at one end. Average loss of the fiber cable shows 0. 81dB/km including splice loss and the average bandwidth over the 17. 3km distance is 170MHz.

• Journal of the Korea Concrete Institute
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• v.14 no.4
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• pp.513-520
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• 2002

This study is to evaluate the structural performance of columns in concrete moment frame. For this purpose the results of previous experimental studies were collected and compared. The experimental variables considered in this study are existance of lap splice within the possible plastic hinge region during an earthquake, ratio of longitudinal reinforcement axial load and the transverse reinforcement ratio. The strength, deformation, ductility capacity and the length of plastic hinge are compared in this study.

• Korean Journal of Plant Resources
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• v.23 no.6
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• pp.526-534
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• 2010

Genomes of clusters of related eukaryotes are now being sequenced at an increasing rate. In this paper, we developed an accurate, low-cost method for annotation of gene prediction and exon-intron structure. The gene prediction was adapted for delta 1-pyrroline-5-carboxylate-synthetase (p5cs) gene from China wild-type of the halophytic Leymus chinensis (Trin.), naturally adapted to highly-alkali soils. Due to complex adaptive mechanisms in halophytes, more attentions are being paid on the regulatory elements of stress adaptation in halophytes. P5CS encodes delta 1-pyrroline-5-carboxylate-synthetase, a key regulatory enzyme involved in the biosynthesis of proline, that has direct correlation with proline accumulation in vivo and positive relationship with stress tolerance. Using analysis of reverse transcription-polymerase chain reaction (RT-PCR) and PCR, and direct sequencing, 1076 base pairs (bp) of cDNA in length and 2396 bp of genomic DNA in length were obtained from direct sequencing results. Through gene prediction and exon-intron structure verification, the full-length of cDNA sequence was divided into eight parts, with seven parts of intron insertion. The average lengths of determinated coding regions and non-coding regions were 154.17 bp and 188.57 bp, respectively. Nearly all splice sites displayed GT as the donor sites at the 5' end of intron region, and 71.43% displayed AG as the acceptor sites at the 3' end of intron region. We conclude that this method is a cost-effective way for obtaining an experimentally verified genome annotation.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.4
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• pp.211-222
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• 2016

Reinforced concrete shear walls with deficient reinforcement details are tested under cyclic loading. The deficiency of reinforcement details includes insufficient splice length in U-stirrups at the ends of horizontal reinforcement and boundary column dowel bars found in existing low- to mid-rise Korean buildings designed non-seismically. Three test specimens have rectangular, babel and flanged sections, respectively. Flexure- and shear-controlled models for reinforced concrete shear walls specified in ASCE/SEI 41-13 are compared with the flexural and shear components of force-displacement relation extracted separately from the top displacement of the specimen based on the displacement data measured at diverse locations. Modification of the shear wall models in ASCE/SEI 41-13 is proposed in order to account for the effect of bar slip, cracking loads in flexure and shear. The proposed modification shows better approximation of the test results compared to the original models.

• Earthquakes and Structures
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• v.15 no.4
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• pp.419-429
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• 2018

The seismic vulnerability analysis of multi-span bridges can be based on the response of the piers, provided that deck, bearings and foundations remain elastic. The lateral response of an RC bridge pier can be affected by different mechanisms (i.e., flexure, shear, lap-splice or buckling of the longitudinal reinforcement bars, second order effects). In the literature, simplified formulations are available for mechanisms different from the flexure. On the other hand, the flexural response is usually calculated with a numerically-based Moment-Curvature diagram of the base section and equivalent plastic hinge length. The goal of this paper is to propose a simplified analytical solution to obtain the Moment-Curvature relationship for hollow circular RC sections. This based on calibrated polynomials, fitted against a database comprising 720 numerical Moment-Curvature analyses. The section capacity curve is defined through the position of 6 characteristic points and they are based on four input parameters: void ratio of the hollow section, axial force ratio, longitudinal reinforcement ratio, transversal reinforcement ratio. A case study RC bridge pier is assessed with the proposed solution and the results are compared to a refined numerical FEM analysis, showing good match.

• Journal of the Korean Society for Advanced Composite Structures
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• v.2 no.2
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• pp.13-19
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• 2011

This paper presents the stress distribution of the damaged butt joint of steel plate using CFRP laminates when the flange in tension zone of steel box girder is welded by butt welding. When CFRP sheets are patched on tension flange of steel-box girder, the stress distribution of a vertical and normal direction on damaged welding part is shown as parameters such as a variation of the thickness of adhesive, the overlap length with steel, and the modulus of elasticity of CFRP sheets. For the study, we wrote the computer program using the EAS(Enhanced assumed strain) finite element method for plane strain that has a very fast convergency and exact stress for distorted shape.

• Advances in materials Research
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• v.8 no.1
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• pp.25-36
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• 2019

The utilization of fibre in concrete production not only solves the problem of disposing this solid waste but helps conserve natural resources. This study investigated the effect of waste aluminum shavings on bond strength of laterized concrete. Laterized concrete spliced beams of $150{\times}250{\times}2150mm$ and $175{\times}275{\times}2300mm$ were prepared. Fifteen specimens with 16 mm and 20 mm were cast with the addition of aluminium shavings at varying percentages of 1vol%, 1.5vol% and 2vol%; another ten specimens with 16 mm and 20 mm diameter bars at 0% of aluminium shavings were cast as control. Concrete cubes of number were prepared, three taken for each set of various percentages of aluminium shavings were used to determine the concrete strength. It was observed from the analysis that the compressive strength decreased as the percentage of aluminium shavings increased, while the aluminium shavings increased the bond between concrete and steel. However, for normal concrete there was an increase in bond resistance with increase in aluminium shavings. The bond resistance of 16 mm was found to be higher than that of 20 mm in all the specimens tested.

• Journal of Korean Society of Steel Construction
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• v.14 no.4
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• pp.481-487
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• 2002

Currently, the load transfer's mechanism from a beam to a column has yet to ve clarified in a concrete filled steel tubular (CFT) structure with a connection type of an exterior diaphragm. The loads for each floor are transferred to the concrete core from a steel beam through ha contacted face between an in-filled concrete and the interior surface of a steel tube. Thus, a Push-Out test was performed to investigate the load transfer mechanism. A total of 30 samples were tested to confirm the bond stress and/or axial load distribution between a steel tube and in-filled concrete for CFT column. The main parameters considered for this study included concrete type, steel tube-shape/length, and the effect of a weld joint wit ha backing strip for a column splice. Test results were summarized to confirm load transfer behavior between a concrete and steel tube for each experimental parameter, using the analytical approach to verify experimental results.

• Molecules and Cells
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• v.26 no.2
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• pp.175-180
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• 2008

$I{\kappa}B$ kinase (IKK), the pivotal kinase in signal-dependent activation of nuclear factor-${\kappa}B$ (NF-${\kappa}B$), is composed of multiple protein components, including IKK ${\alpha}/{\beta}/{\gamma}$ core subunits. To investigate the regulation of the IKK complex, we immunoaffinity purified the IKK complex, and by MALDI-TOF mass spectrometry identified a splice variant of zinc finger protein 268 (ZNF268) as a novel IKKinteracting protein. Both the full-length and the spliced form of the ZNF268 protein were detected in a variety of mammalian tissues and cell lines. The genes were cloned and expressed by in vitro transcription/translation. Several deletion derivatives, such as KRAB domain (KRAB) on its own, the KRAB/spacer/4-zinc fingers (zF4), and the spacer/4-zinc fingers (zS4), were ectopically expressed in mammalian cells and exhibited had different subcellular locations. The KRAB-containing mutants were restricted to the nucleus, while zS4 was localized in the cytosol. TNF-${\alpha}$-induced NF-${\kappa}B$ activation was examined using these mutants and only zS4 was found to stimulate activation. Collectively, the results indicate that a spliced form of ZNF268 lacking the KRAB domain is located in the cytosol, where it seems to play a role in TNF-${\alpha}$-induced NF-${\kappa}B$ activation by interacting with the IKK complex.