• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.107-108
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• 2012

The study on the strength prediction using Maturity is mainly focused on, but the study on the concrete mixing blast furnace slag powder is insufficient. The purpose of this study is to investigate the relationships between compressive strength and equivalent age by Maturity function and is to compare and examine the strength prediction of concrete mixing Blast Furnace Slag Power using ACI and Logistic Curve prediction equation. So it is intended that fundamental data are presented for quality management and process management of concrete mixing Blast Furnace Slag Power in the construction field.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.10
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• pp.833-839
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• 2012

In this paper, we analyze the reconstruction error in the modeling of flow field on BFS(Backward Facing Step). In order for the mathematical modelling of a density on the field, the spatial and temporal modes are extracted by POD(Proper Orthogonal Decomposition) method. After formulating the modeling error, we summarize the relationship between the energy strength and the reconstruction errors. Moreover the allowable modeling error limits in the flow control point of view are confined by analysing in the frequency domain as well as time domain of the reconstructed data.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.649-654
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• 2002

In order to suggest recyling and handling method of a tailing, observe it's physical and chemical properties, make an quality test of aggregates which are used a tailing and then examine a applied possibility in architectural materials. Tailing has a ununiform and many-side shape and it is organized quartz, muscovite, calcite, montmorillonite. pH is 6.86-7.28 and the result of leaching test is that Hg and Pb exceed of a standard. The specific gravity of aggregates which are used tailing is 1.95-2.23 and the absorption factor is 9-14.67%. The result of test for abrasion and crushing of aggregates which are used BFS is very excellent. The heavy metal is stabilized but a eruption property of Hg is similar to original sample.

• Journal of Sensor Science and Technology
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• v.28 no.6
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• pp.360-365
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• 2019

A polyvinylidene fluoride (PVDF)-based film speaker is successfully fabricated with enhanced bass sound by incorporating buckled nanospring carbon nanotubes (NS-CNTs) as fillers. Various concentrations up to 1-7 wt% of uniformly dispersed buckled NS-CNTs are loaded to increase the beta (β)-phase fraction, crystallinity, and dielectric constant of the speaker, and this results in the bass part enhancement of about 19 dB full scale (dBFS) at 7 wt% filler loading of the piezoelectric film speaker.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.145-148
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• 2002

This study is performed to properties of low heat concrete using blast furnace slag powder and gypsum. The test result shows that the air content is in the range of $4.1%{\sim}5.1%$, the unit weight is in the range of $2,306kg/m^3{\sim}2,334kg/m^3$. The compressive strength of concrete mixed blast furnace slag(BFS) low than ordinary portland cement(OPC) at the curing age of 7days, but it is high or same at the curing age of 28days. And the natural gypsum shows superior compressive strength than the chemical gypsum.

• Earthquakes and Structures
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• v.12 no.2
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• pp.191-200
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• 2017

In this paper, the seismic performance of reinforced concrete braced frames (RC-BF) under far- and near-fault motions was investigated. Four-, eight-, 12- and 16-story RC-BFs were designed on the basis of a code-design method for a high risk seismic zone. Nonlinear static and dynamic analyses of the frames have been performed using OpenSees software. To consider diverse characteristics of near-fault motions, records with forward-directivity and fling-step effects were employed. From the results obtained in the analytical study it is concluded that the used design method was reasonable and the mean maximum drift of the frames under all ground motion sets were in acceptable range. For intermediate- and high-rise buildings the near-fault motions imposed higher demands than far-faults.

• Journal of the Korea Computer Industry Society
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• v.4 no.12
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• pp.1093-1102
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• 2003

The dynamic nature of the World Wide Web challenges Search engines to find relevant and recent pages. Obtaining important pages rapidly can be very useful when a crawler cannot visit the entire Web in a reasonable amount of time. In this paper we study way spiders that should visit the URLs in order to obtain more “important” pages first. We define and apply several metrics, ranking formula for improving crawling results. The comparison between our result and Breadth-first Search (BFS) method shows the efficiency of our experiment system.

• JSTS:Journal of Semiconductor Technology and Science
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• v.17 no.1
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• pp.162-166
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• 2017

Earliest virtual deadline zero laxity (EVDZL) algorithm is proposed for mobile GPU schedulers for its improved responsiveness. Responsiveness of user interface (UI) is one of the key factors in evaluating smart devices because of its significant impacts on user experiences. However, conventional GPU schedulers based on completely fair scheduling (CFS) shows a poor responsiveness due to its algorithmic complexity. In this letter, we present the EVDZL scheduler based on the conventional earliest deadline zero laxity (EDZL) algorithm by accommodating the virtual laxity concept into the scheduling. Experimental results show that the EVDZL scheduler improves the response time of the Android UI by 9.6% compared with the traditional CFS scheduler.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.469-470
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• 2010

The high-strength concrete(HSC) compared to normal concrete represents higher autogenous shrinkage due to lower water-to-binder ratio(W/B) and supplementaries, fly ash(FA) and granulated blast-furnace slag(BFS), etc. The potential of early age cracking which reduces durability of concrete structures is normally influenced by autogenous shrinkage and degree of restraint. Therefore, this paper studies on the evaluation of the characteristics of autogenous shrinkage for HSC, ultra-high-strength concrete(UHSC) containing admixtures by experimental test and the test results are compared with existed prediction models.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.105-108
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• 1997

To reduce design period, demands for rapid prototyping system is increasing. Among the rapid prototyping system, as a concept modeler, 3D Printer appears before the footlights. In spite of short production time and convenience, 3D Printer causes post processing problem. And that is too slow to adapt to the demand of workshop. In this research, we developed a system for reducing build time and roughness using splitting operation. Also, propose BFS(B-rep For STL) data structure to maintain model data, split STL model and implement Euler Operation for input and output.