• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.127-129
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• 2008

EPR spectroscopic technique was applied for a quantitative analysis of Eu(II) for a speciation of europium in a LiCl-KCl eutectic melt. By adopting the first absorption line of each isotopes (151Eu and 153Eu), a calibration plot was obtained. The calibration of the EPR intensity shows a good linearity according to the amount of Eu(II). The EPR intensity was identified to increase proportionally with a decrease of the attenuation parameter for EPR microwave power. The fluorescence technique was used qualitatively to find whether either of Eu(II) or Eu(III) ions exists in a molten salt sample. The ICP-AES technique was also adopted to determine the total concentration of europium in the sample, since EPR is only sensitive for detecting the Eu(II) ion. The extent of the reduction of Eu(III) in the LiCl-KCl eutectic melt at 723 K was determined by using this technique.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.6
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• pp.2251-2270
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• 2015

More than 1 billion mobile apps (smartphone applications) have been released worldwide. Competition among developers of apps that are available in app stores has intensified because of increasing demand. App icons with an appealing design can instantly increase attention. Miryoku Engineering methods were used and combined with the Kansei interface model to examine the relationship between attractive icons and users. The evaluation grid method (EGM) is a qualitative method that was used to evaluate the icons, and Quantification Theory Type I is a quantitative method that was used to analyze the influence of design elements in icons. Eight attractive factors of app icons were determined using EGM, and six specific factors were identified using questionnaires. The quantitative results indicated that user cognition and emotion were influenced by the various design elements. The impact on the attractive factors of a single design element differed among users with diverse backgrounds. App icons were assessed on the basis of aesthetics to identify attractive factors and thereby assist designers in understanding and implementing design elements and improving the overall visual appeal of their apps. The result of this investigation is crucial to the presentation of app icons in online app stores.

• Journal of the Korean housing association
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• v.28 no.1
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• pp.9-17
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• 2017

This study investigates and analyzes (1) the status of neighborhood commercial facilities, (2) the location of neighborhood commercial facilities and (3) the users' viewpoint of them for the purpose of establishing the revitalizing factors of neighborhood commercial facilities within permanent rental housing complexes. This study attempts to determine the factors that revitalize neighborhood commercial facilities through quantitative factor analysis based on the analysis of the basic status and purpose of neighborhood commercial facilities using the basic status of permanent rental housing complexes and the quantitative data on neighborhood commercial facilities within these complexes. A survey investigating the residents' perception of neighborhood commercial facilities was conducted to analyze the qualitative aspects neighborhood commercial facilities within permanent rental housing complexes. The factors affecting the revitalization of neighborhood commercial facilities were analyzed by quantifying the actual problems perceived by the users and the elements of their use patterns. From these analysis results, it was found that the factors are not independent from one another, but organically affect one another. It is expected that more meaningful data will be obtained if future studies conduct correlation analysis and weighted value analysis on each factor based on the findings of the present study.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.5
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• pp.221-229
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• 1999

We examined the governing factors of fatigue limit in annealed and austempered ductile iron specimens machined micro hole(dia.<0.4mm) in rotary bending fatigue test. Also, the quantitative relationship between fatigue limit and maximum defect size in specimens was investigated. Artificial defect(micro-pit type, dia.<0.4mm) on specimen surface did not bring about an obvious reduction of fatigue limit in austempered ductile iton(ADI) as compared with annealed ductile iron. According to the investigation of ${\sqrt{area}}_c$ which is the critical defect size to crack initiation at artificial defect, ${\sqrt{area}}_c$ of ADI was larger than that of annealed ductile iron. This shows that the situation of crack initiation at artificial defect in ADI is more difficult in comparison with annealed ductile iron. Maximum defect size is one of the important parameters to predict fatigue limit. And, the quantitative relationship, between the fatigue limit ${\sigma}_{\omega}$ and the maximum defect size ${\sqrt{area}}_{max}$ can be expressed to ${\sigma}_{\omega}^n{\cdot}{\sqrt{area}}_{max}=C_2$ where, $C_2$ are constant. Moreover, it is possible to explain the difference in fatigue limit between, austempered and annealed ductile iron by introducing the parameter ${\delta}(=N_{sg}/N_{total})$in a plain spectimen.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.05c
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• pp.25-28
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• 2001

The objectives of this paper are to demonstrate the electrical degradation phenomena with Si atom's behaviors in the grainboundary of semiconducting ZnO ceramics. The ZnO ceramic devices used in this investigation were fabricated by standard ceramic techniques. Especially, $SiO_2$ were added to analyze the degradation characteristics with Si and sintered in oxygen ambient at $1300^{\circ}C$. The conditions of DC degradation test were $115{\pm}2^{\circ}C$ for 13h. Using XRD and SEM, the phase and microstructure of samples were analyzed respectively. E-J analysis was used to determine $\alpha$. Frequency analysis was accomplished to understand $R_g$ and $R_b$ at the equivalent circuit. Electrical stability improved as the amount of $SiO_2$ addition increased. This results were explain by the quantitative analysis and the line scanning method of EPMA.

• Nuclear Engineering and Technology
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• v.34 no.3
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• pp.259-267
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• 2002

NFPA-803 has been referred as the Fire Protection Standard at the Nuclear Power Plants of Pressurized Water Reactor. This Standard has been used as the fire protection regulation, containing prescriptive requirements with deterministic methodology. Recently, with cumulative efforts by the U.S. Nuclear Regulatory Commission and Utilities in America to establish a new Standard, including a quantitative evaluation methodology, NFPA-805, the Performance-Based Standard for FIRE Protection for Light Water Reactor Electric Generating Plants was issued and approved by the American National Standards Institute as an American National Standard with an effective date of February 9, 2001. This paper presents an analysis result from the computer modeling for the fire simulation In addition, it proposes the idea that this kind of analytic method can be available for the facilities design of fire prevention and protection fields, as well as an evaluation for the fire suppression system with a quantitative analysis for the thermal phenomena in fire compartments in Nuclear Power Plants.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.1
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• pp.74-82
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• 2004

Planar laser-induced fluorescence(PLIF) has been widely used to obtain two dimensional fuel distribution. Acetone PLIF is chosen because fluorescence signal from acetone as a fluorescent tracer is less sensitive to oxygen quenching than other dopants. Acetone PLIF is applied to measure quantitative air excess ratio distribution in an engine fueled with LPG. Acetone is excited by KrF excimer laser (248nm) and its fluorescence image is acquired by ICCD camera with a cut-off filter to suppress Mie scattering from the laser light. For the purpose of quantifying PLIF signal, an image processing method including the correction of laser sheet beam profile is suggested. Raw images are divided by each intensity of laser energy and profile of laser sheet beam. Inhomogeneous fluorescence images scaled with the reference data, which is taken by a calibration process, are converted to air excess ratio distribution. This investigation shows instantaneous quantitative measurement of planar air excess ratio distribution for gaseous fuel.

• Journal of Korean Institute of Industrial Engineers
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• v.39 no.3
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• pp.212-221
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• 2013

As the convergence among technologies is reorganizing industry sectors, it is quite important to evaluate the probability of technological convergence, and to analyze how the technologies in a certain industry sector affect the same or other industry sectors. As a result, the large number of studies have been focused on the industry convergence. However, most of them have dealt mainly with case studies or strategy and policies and few efforts have been made to study it using quantitative data. The investigation of industry convergence using quantitative data will help understand the characteristics of industry and forecast the future of the industry from an objective point of view. Therefore, this research proposes a methodology to evaluate the possibilities of industry convergence using patent data. In particular, we emphasize the possibilities of technology convergence and suggest a technology relationship matrix to evaluate the technology convergence, as an antecedent of industry convergence. The feasibility and utility of the suggested methodology was verified with a case study on the convergence of IT and BT. The research results are expected to provide a useful guideline for developing a measure of convergence.

• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2371-2376
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• 2021

As the γ-ray energy increases, a reconstructed image becomes noisy and blurred due to the penetration of the γ-ray through the coded mask. Therefore, the thickness of the coded mask was increased for high energy regions, resulting in severely decreased the performance of the detection efficiency due to self-collimation by the mask. In order to overcome the limitation, a modified uniformly redundant array γ-ray imaging system using dual anti-mask method was developed, and its performance was compared and evaluated in high-energy radiation region. In the dual anti-mask method, the two shadow images, including the subtraction of background events, can simultaneously contribute to the reconstructed image. Moreover, the reconstructed images using each shadow image were integrated using a hybrid update maximum likelihood expectation maximization (h-MLEM). Using the quantitative evaluation method, the performance of the dual anti-mask method was compared with the previously developed collimation methods. As the shadow image which was subtracted the background events leads to a higher-quality reconstructed image, the reconstructed image of the dual anti-mask method showed high performance among the three collimation methods. Finally, the quantitative evaluation method proves that the performance of the dual anti-mask method was better than that of the previously reconstruction methods.

• Journal of People, Plants, and Environment
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• v.22 no.5
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• pp.481-488
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• 2019

The purpose of this study is to suggest how to manage healing forests. Field investigation and surveys were conducted to produce results and 313 questionnaires collected from workers in the forestry sector and ordinary people were analyzed. The results were as follows: it is required to preserve flowering plants, scenic trees, and ecological trees in the understory vegetation, and to remove trees that block the forest landscape, leaving about 50 to 60 percent of the understory vegetation. The preferred density order of broadleaf trees was analyzed as follows: Betula platyphylla > Liriodendron tulipifera > Quercus acutissima. The preferred density order of coniferous trees was analyzed as follows: Abies holophylla > Cryptomerias japonica and Chameacyparis obtusa > Larix kaempferi > Pinus densiflora > Pinus koraiensis. The preferred density in healing forests was 81-89% compared to the number of residual trees for quantitative thinning. Specifically, the preferred density were 87% for P. koraiensis, 86% for L. kaempferi, 81% for P. densiflora, 83% for C. japonica, 84% for C. obtusa and 89% for Q. acutissima. In the case of healing forests, it is recommended to periodically conduct a small-scale thinning with different densities according to the species and diameter of trees based on the results of this study.