• Journal of Conservation Science
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• v.26 no.4
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• pp.361-370
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• 2010

The open pore of stone cultural heritage is not expected to have an effect only by consolidation, and it has a drawback that only the internal wall adheres and gets consolidated due to the incrase of liquidity caused by the low viscosity and difference of materials in the case of filling with high molecules synthetic resins. Therefore, this research selected the effective filler for Three-storied Stone Pagoda at the West of Gameunsaji Site through the verification of filling effects of materials using the information about various fillers based on minerals. As the result of filler experiment, got filled with the combination of KSE 500 STE + KSE Filler A${\cdot}$KSE Filler B that is the same as the Member or has very similar properties. The total surface area of the west stone is $252.6m^2$ and the area where the internal opening has been developed is $17.77m^2$(7.03%) requiring a task that fills the internal($24,885m{\ell}$).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6A
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• pp.399-408
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• 2011

Development of smart sensors for structural health monitoring and damage detection has been advanced remarkably in recent years. Nowadays fiber optic sensors, especially fiber Bragg grating (FBG) sensors, have attracted many researchers' interests for their attractive features, such as multiplexing capability, durability, lightweight, electromagnetic interference immunity. In this paper, a damage detection approach of jacket-type offshore structures by principal component analysis (PCA) technique using FBG sensors are presented. An experimental study for a tidal current power plant structure as one of the jacket-type offshore structures was conducted to investigate the feasibility of the proposed method for damage monitoring. It has been found that the PCA technique can efficiently eliminate environmental effects from measured data by FBG sensors, resulting more damage-sensitive features under various environmental variations.

• Journal of The Korean Association For Science Education
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• v.23 no.5
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• pp.531-543
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• 2003

This study aims to investigate that scientifically gifted students have distinctive science related attitudes in comparison with general students. In addition, this study examines the relationship among science related attitudes, intelligence, and science process skills. Two hundred sixty-six middle school students (169 boys, 97 girls) who enrolled at the Incheon Science Elite Program and 220(133 boys, 87 girls) students in a regular middle school participated in the present study. Research findings support that gifted students have more positive science related attitudes than general students as well as higher intelligence and science process skills. At last, low and non-significant correlation coefficients with attitudes and cognitive factors were found in gifted groups, whereas some significant correlations were found in general students.

• Spatial Information Research
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• v.22 no.6
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• pp.45-54
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• 2014

Establishment of safety net for the socially disadvantaged attracts large attention because of the recent crime increasing against vulnerable groups. For the successful establishment of social safety net, the test-bed for evaluation and realization of crime-related research results is required. However, previous R&D test-bed projects such as The Korean Land Specialization Program or U-Eco City project remains only to the stage of verification. Therefore, there are limitedness for realization of result technologies or sustainable operation & management of test-bed after projects finished. So, sustainable operation & management system and guideline of test-bed are necessary. Therefore, this study reviews the strengths and weaknesses of existing test-bed cases and intelligent security researches. After reviewing, the concept of a Intelligent Security Test-bed is established and appropriate test-bed selection criteria is also suggested. Based on objective criteria, selected test-bed can achieve sustainable management even after finishing the project and contribute the construction of standard model for citizen's safety.

• Journal of the Korea Society for Simulation
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• v.21 no.3
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• pp.11-16
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• 2012

Simulation is the imitation of the operation of a real-world process or system over time. It concerns the study of the operating characteristics of real systems. Typically, a simulation project consists of several steps such as data collection, coding, model verification, model validation, experimental design, output data analysis, and implementation. Among these steps of a simulation study this paper focus on statistical analysis methods of simulation output data. Specially, we explain how to develop confidence interval estimators for mean ${\mu}$ in terminating and non-terminating simulation cases. We, then, explore the estimation techniques for $f({\mu})$, where the function $f({\bullet})$ is a nonlinear that is continuously differentiable in a neighborhood of ${\mu}$ with $f'({\mu}){\neq}0$.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1981.05a
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• pp.38.2-39
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• 1981

Speech reception threshold is a base for word discrimination testing, but it also serves as a check for the reliability of pure tone audiogram. In order to investigate the correlation between SRT and PTA these tests were carried out in patients with conductive hearing loss and normal hearing, using Grason-Stadler 1702 Audiometer. The results were as follows; 1) The difference between the scores of SRT and PTA's was 2.4 dB with a range of -3.3 dB∼+8.3 dB in conductive hearing loss, and was 1.9 dB with a range of -6.7 dB∼+5 dB in normal hearing group. 2) The difference between the scores of SRT and each speech frequency of PTA was 6 dB at 500 Hz, 3 dB at 1,000 Hz and 8.8 dB at 2,000 Hz in conductive hearing loss, and 3 dB at 500Hz, 2 dB at 1,000Hz, and 5dB at 2,000Hz in normal hearing group.

• Archives of design research
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• v.15 no.3
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• pp.167-180
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• 2002

This study investigates effective ways to help users form a correct mental model of the hierarchical information space (HIS) in small display. The focus is the effect of color cue on understanding the structure and navigating the information space. The concept of color space (CS) corresponds well to the HIS - one color has a unique position in the CS as a piece of information does in HIS. In this study, we empirically examined two types of color cue, namely, categorical and depth cue. Hue was used as a categorical cue and tone was used as a depth cue. In our experiment, we evaluate the effectiveness of the color cues in the mobile internet system. Subjects were asked to perform four searching tasks and four comparison tasks. The results of experiment reveal that the categorical cues significantly improve the user's mental model whereas decrease navigation performances. The depth cues cannot aid in understanding the HIS as well as improve navigation performances. This study concludes with limitations of the study and descriptions of future studies.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.1
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• pp.13-21
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• 2020

Surrogate models have been used for the rapid estimation of six-DOF aerodynamic coefficients in the context of the design and control of a missile. For this end, we may generate highly accurate surrogate models with a multitude of aerodynamic data obtained from wind tunnel tests (WTTs); however, this approach is time-consuming and expensive. Thus, we aim to swiftly predict aerodynamic coefficients via co-Kriging using a few WTT data along with plenty of computational fluid dynamics (CFD) data. To demonstrate the excellence of co-Kriging models based on both WTT and CFD data, we first generated two surrogate models: co-Kriging models with CFD data and Kriging models without the CFD data. Afterwards, we carried out numerical validation and examined predictive trends to compare the two different surrogate models. As a result, we found that the co-Kriging models produced more accurate aerodynamic coefficients than the Kriging models thanks to the assistance of CFD data.

• Informatization Policy
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• v.22 no.1
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• pp.73-95
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• 2015

This research has a purpose to verify whether the Internet diffusion through the Official Development Assistance (ODA) can bring about democratic changes in authoritarian political system of developing countries. This research has found out that IT ODA has 'positive(+)' effect on the Internet diffusion in recipient countries. It seems to support the expectation of donor countries that they can lead the political democratization by constructing infrastructure and promoting the use of the Internet. However, as the impact of IT ODA on the Internet diffusion is not considerable as well as the Internet diffusion has no strong influence on the development of democracy in developing countries, and also each of these aspects of countries looks different, it is hard to see that the democratization hypothesis based on the optimistic technological determinism is reasonable. Therefore, this paper argues that IT ODA must be based on not blind optimism that IT transfer will lead to the political democratization in developing countries, but the social structuralism which is based on distinctiveness and uniqueness of countries. and suggests that the discuss of the effect of IT ODA proceed with the constructive way.

• Fire Science and Engineering
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• v.31 no.4
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• pp.86-94
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• 2017

In the present study, a Cook Book method and a Static System Analysis method were compared with each other on the basis of a seismic design criteria of fire-fighting facilities and analyzed. The Cook Book method is analyzed by dividing a pipeline in each same section. In this method, a stress analysis is not possible except for the section analyzed in such a way that a brace is designed according to the weight of pipe, water and pipe fitting. To the contrary, in case of the Static System Analysis method, the stress analysis for the whole pipeline can be performed because the whole pipeline is regarded as a single structure. For the fatal stress values locally generated, it is necessary to actively perform a pipeline analysis by installing a device capable of locally relieving the stress of the pipeline. In Korea, only the Cook Book method is provided as the seismic design criteria of fire-fighting facilities, which causes many problems with diversification of seismic design. Thus, it is necessary to apply the seismic design method of the pipeline by using various kinds of engineered Static System Analysis methods.