• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.921-922
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• 2010

• Journal of the Korean Statistical Society
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• v.29 no.1
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• pp.17-27
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• 2000

In this paper, we develop noninformative priors that are used for estimating the reliability of stress-strength system under the Burr-type X model. A class of priors is found by matching the coverage probabilities of one-sided Bayesian credible interval with the corresponding frequentist coverage probabilities. It turns out that the reference prior as well as the Jeffreys prior are the second order matching prior. The propriety of posterior under the noninformative priors is proved. The frequentist coverage probabilities are investigated for samll samples via simulation study.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04b
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• pp.457-462
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• 1998

An experimental study was carried out for hybrid steel beams with reinforced concrete ends. The purpose is to examine the shear strength and to develop the design methodology of the RC-S connection region. Tested were four beams which included a reference beam and three beams with various parameters. The reference beam was used to make a comparison with remaining specimens. The test parameters were focused mostly on the concentrated shear reinforcements. The ratio of concentrated shear reinforcements and their types were investigated in this study.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.5
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• pp.411-418
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• 2008

In this work, the effect of strength mismatch on plastic limit loads is quantified for similar metal weld plates with cracks under tension load, via three-dimensional, small strain elastic-perfectly plastic finite element analyses. Relevant variables related to plate geometry and crack length are systematically varied, in addition to the weld width. An important finding is that mis-match limit loads can be uniquely quantified through strength mis-match ratio and one geometry-related parameter. Based on the proposed limit load solutions, reference stress based J-integral estimates is also investigated. When the reference stress is defined by the mis-match limit load, predicted J-integral values agree overall well with FE results.

• Nuclear Engineering and Technology
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• v.54 no.7
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• pp.2550-2563
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• 2022

This study performed a precise dynamic finite element time history elastic-plastic seismic analysis considering the welds, which have been not considered in design stage, on the nuclear components subjected to severe seismic loadings such as beyond-design basis earthquakes for sustainable nuclear power plants. First, the dynamic finite element elastic-plastic seismic analysis was performed for a general design practice that does not take into account the welds of the pressurizer surge line system, one of safety class I components in nuclear power plants, and then the reference values for the accumulated equivalent plastic strain, equivalent plastic strain, and von Mises effective stress were set. Second, the dynamic finite element elastic-plastic seismic analyses were performed for the case of considering only the mechanical strength over-mismatch of the welds as well as for the case of considering both the strength over-mismatch and welding residual strain. Third, the effects of the strength over-mismatch and welding residual strain were analyzed by comparing the finite element analysis results with the reference values. As a result of the comparison, it was found that not considering the strength over-mismatch may lead to conservative assessment results, whereas not considering the welding residual strain may be non-conservative.

• Journal of the Korean GEO-environmental Society
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• v.2 no.4
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• pp.73-81
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• 2001

Soil cement has been the typical material for the pavement and soft ground improvement. It has not been used up to date because that quality control is not easy and durability is not long enough for practical application. Since environmental influence is important, the application of high strength soil cement pavement has been increased for pedestrian roads of the garden, golf courses and sidewalks recently. In this study, the reference table was suggested for mixing design with appling statistical experimental technique to reference table. The reference table showed the relationship among improved strength, Soilcrete stabilizer, fine sand ratio and superplasticizer agent. The objective soil used in this study was the soft marine clay that is widely found in Korea, the compressive strength range of improved soil was between $50{\sim}150kg/cm^2$.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.107-110
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• 2006

The purpose of this study is to suggest a reference data for the development of high workable and normal strength concrete using Polycarboxylate superplasticizer and granulated blast furnace slag as concrete admixtures. So in this study, it is quantitatively evaluated the workability, compressive strength, the heat of hydration and dry shrinkage of high workable concrete on normal compressive strength($21{\sim}27MPa$) for the practical use in construction field. As a result of this study, it is appeared that the performance of high workable and normal strength concrete is superior than that of ready-mixed concrete of the same strength through the B/P tests in the plants.

• Proceedings of the Korea Concrete Institute Conference
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• 1991.04a
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• pp.19-22
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• 1991

In order to the Utilization of Fly ash, The Properties of cement Mortar use of Fly ash based on Mixing rate, strength of mortar, W/C+F and quantity of Fly ash, Flow value, and unit weight are investigated. So follow result are unit weight of mortar of Fly ash is about 2014 Kg/㎥, Compressive strength of mortar is 50-404 Kg/$\textrm{cm}^2$ and beneficial reference to the utility of domestic Fly ash were obtained.

• Proceedings of the Korea Concrete Institute Conference
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• 1991.10a
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• pp.30-33
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• 1991

To reinforce the foundation of building, the spun concrete pile is mostly used with consider the strength, economiability, durability, and etoetera. So, this study is designed for analyze the compressive strength of centryfugal manufacture concrete than that of normal concrete, and is aimed for presenting the reference data to the practical use of pile manufacture.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.9
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• pp.199-206
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• 2019

Experimental study on the durability characteristics to examine the feasibility of concrete with high water-tightness and self-healing performance to minimize maintenance of concrete for artificial ground is as follows. 1) When blending agent, swelling agents, and curing accelerator were added on the ternary system cement with blast-furnace slag fine particles and fly ash to give a self-healing property, higher blending strengths by 82% at design standard strength of 24MPa and by 74% at design strength of 30MPa, respectively could be obtained. 2) The permeability test for the specimens having high water-tightness and no shrinkage showed that the permeability was reduced at maximum of 98%. However, the permeability was decreased as the design strength was increased, showing the reduction rate of 87% at the design strength of 50MPa. 3) The depth of carbonation of blast-furnace slag and fly ash was increased in all the specimens compared with those of OPC only. However, as the material age was increased, carbonation penetration depth was decreased compared with the reference blend. 4) Compared with the reference blending using only OPC, the freeze-thaw resistance was higher in the case of blending with 40% of blast-furnace slag and 10% of fly ash at the design standard strength of 50MPa. In addition, the freeze-thaw resistance in general was superior in the design standard strength of 50MPa with the lower water-binder ratio (W/B) as compared with the design standard strength of 24MPa and 30MPa with the high water-binder ratios.