• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.109-114
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• 2008

Purpose: To assess the reproducibility and repeatability for each color vision test method. Methods: The subjects for color vision test were 30 students without congenital color vision deficiency and they major in optometry in a university, Korea. The type of color vision test selected for this study were Hans color vision test, Hans 15 hue test and Lanthony D 15 hue test. The Ishihara test was added for assessment of reliability of inter-tester. Results: All of the subjects were classified into normal at pseudoisochromatic plates, but one subject's result showed mild blue-yellow color deficiency at Hue discrimination. Results of 3 repeated test for subjects and inter-tester examination showed no errors at pseudoisochromatic plates. There were differences in mild errors among repeated test at Hue discrimination, but no differences were found in the results of repeated test to classify color vision deficiency. Conclusion: Each tester had better be more skilled to test even simple color vision test for eliminating the possibility of mild errors. Each subject might just as well be careful in color vision test. It is required to test both method of pseudoisochromatic plates and Hue discrimination in screening test.

• Resources Recycling
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• v.21 no.2
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• pp.53-58
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• 2012

A laboratory study was carried out to recover KI crystals with high purity from a waste solution generated from the production of polarizing film for LCD industry. The waste solution contains 1 to 4% KI, and other impurities such as B, PVA and etc. More than 95% purity of KI crystals were produced through refining process such as vacuum evaporation and fractional crystallization. Most of B compounds and impurities were removed by concentrating the waste solution until KI content reached about 50%. The KI crystals were washed with solvents to remove most of PVA which gave result in producing 99.5% purity of crystals. The overall recovery of KI was about 90% during the concentration process.

• Journal of agriculture & life science
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• v.44 no.6
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• pp.45-50
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• 2010

Soil characteristics by site types (slope, topography and stand) were analyzed to provide the basic information for sustainable management of Nari basin in Ulleung Island. The content of total N of Nari basin was lowest at the north slope, this site had also significantly low soil pH and content of available P. The result of soil pH and content of total N analysis by topography, ranged from 5.13 of summit to 5.59 of plain and from 0.63% of plain to 0.87% of hill, respectively. Soil pH, content of total N and available P by stand were significantly different, which showed that stand types are more significant in explaining the soil properties. Available P content by slope, topography and stand ranged from 2.79 to 8.46 ppm, 3.99 to 8.46 ppm and 5.03 to 11.59 ppm, respectively. It was concluded that forest soil around Nari basin has relatively low available P content compared to other forest soil.

• The Journal of the Petrological Society of Korea
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• v.28 no.2
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• pp.71-83
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• 2019

The volcanic rocks in Saryangdo area are composed of Witseom Andesite, Punghwari Tuff, Araetseom Andesite, Obido Formation, Namsan Rhyolite and Saryangdo Tuff in ascending order. The volcanic rocks has a range of andesite-rhyodacite-rhyolite, which indicates calc-alkaline series and volcanic arc of orogenic belt. In Harker diagrams for trace element and REE pattern, these are also distinguished into so three groups(Witseom Andesite, Araetseom Andesite and Saryangdo Tuff) that each unit is interpreted to have originated in different magma chamber. The Saryangdo Tuff exhibits systematically(chemical zonations that gradually change) from lower dacite to upper rhyolite in section. The systematic sequence of compositional variations suggests that the tuffs were formed by successive eruptions of upper to lower part of a zoned magma chamber in which relatively dacitic magma is surrounded around rhyolitic magma of the central part. The zoned magma chamber was formed from marginal accretion and crystal settling that resulted form magmatic differentiations by fractional crystallization.

• The Journal of the Korea Contents Association
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• v.19 no.2
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• pp.438-449
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• 2019

This study explored the perception of internet media credibility and influencing factors among college students who are routine users of internet-based media. Media literacy competences are of primary interest among others in that users' media literacy such as information evaluation, critical understanding of media, and information sharing are assumed to be related to media credibility. The results of analysis revealed critical understanding ability to be statistically significant and consistently influencing factor. Users with more critical view on media ownership, represented reality, commercial intention of media seemed less likely to trust internet media. Whereas media use motive for information was found to be a strong predicting factor, motive for pleasure showed no relationship with credibility. Based on the findings, suggestions for new research and limitations of the study were discussed.

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.109-115
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• 2023

The extraction and adsorption characteristics for three phenolic ketones with high physicochemical similarity among phenolic compounds, which are alcohol fermentation inhibitors in lignocellulosic biomass hydrolysates, were investigated. The most suitable basic extractant for selectively separating acetosyringone from three phenol ketones by reactive extraction was found to be trioctylphosphine oxide. In addition, it was found that adsorption using XAD16, a polymer neutral resin adsorbent, or physical extraction using hexane, was a suitable separation method for separation of 4'-hydroxyacetophenone (HAP) and acetovanillone (AVO). A five-step fractionation process including extraction and adsorption mentioned above has been first proposed to separate and concentrate the three phenol ketones present at equal mass percentages. When physical extraction with n-hexane and re-extraction with an aqueous NaOH solution were used as the steps 4 and 5 in the fractionation process respectively, it was possible to obtain almost 70% or more of the purity of three phenolic ketones.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1D
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• pp.73-81
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• 2008

Hereafter, the domestic housing industry has to give consequence to the redevelopment and rebuilding of existing housings rather than the supply by developing a new building site, and now those tendencies are rapidly spreading out. Also, because apartment buildings occupies 50% over of the existing housing, its maintenance, repair, remodeling and reconstruction got to be necessary area for the slumming prevention of a residential area and the disaster prevention occurred by durability lowering of the building. Accordingly, C&D waste is rising largely by reason of demolition works in city is increasing. The right management of C&D waste is being one of very important things, but little research has been conducted to estimate correctly C&D waste. In this study is to suggest standard units of C&D waste which can estimate demolition quantity of apartment. This units can estimate easily and correctly C&D waste in demolition works, also can possible use very important material to carry out policy of national waste management.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4D
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• pp.627-634
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• 2006

Now, in a domestic country, the rebuilding and redevelopment of existing houses has been rapidly increasing with an economic growth and the improvement of living condition. As a result of that, a lot of C&D waste has been also produced. Nevertheless, it is not easy to find the research results for appropriate treatment and management of C&D waste in domestic. Therefore this study suggests the optimum deconstruction management system for minimizing construction waste and increasing reuse or recycle rate of material different from traditional demolition. The system makes it possible to plan and manage in advance quantity of C&D waste, demolition methods of each structural elements and application methods of produced C&D waste through an integrated and computerized system. The purpose of the system is ultimately to contribute to minimizing environmental damages and reducing construction waste quantity of a country. This system is largely composed of four modules such as planning of preliminary demolition survey, estimating of demolition quantity, planning of demolition schedule and planning of construction waste management and each module can be also used individually according to the purpose of a user.

• Korean Journal of Clinical Laboratory Science
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• v.49 no.2
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• pp.114-120
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• 2017

There have been many studies to develop methods for predicting diabetes and to prevent diabetes. The validity of glycated hemoglobin (HbA1c), one of the commonly known tools in predicting diabetes, has been verified by many previous studies. In this study, we examined the cutoff value of HbA1c for diabetes and impaired fasting glucose (IFG). Based on this study, we proposed a proper clinical guideline and evaluated the validation of the guideline. Excluding those without blood glucose and HbA1c data, we used the data of 5,161 subjects (2,281 men and 2,880 women) over the age of 20 years from the 2015 Korean National Health and Nutrition Examination Survey. The correlation efficient of fasting plasma glucose (FPG) and HbA1c was 0.79, indicating a strong relationship. Howeve, the correlation efficient of FPG and HbA1c was low, showing 0.27 in non-diabetes, 0.39 in IFG, and 0.66 in diabetes, showing a strong relationship. The cutoff value of HbA1c for predicting diabetes using ROC curve was 6.05% (sensitivity 84.6%, and specificity 92.0%), and AUC was 0.941 (0.937 in men, and 0.946 in women). The cutoff value of HbA1c for predicting IFG using ROC curve was 5.55% (sensitivity 64.5%, and specificity 70.0%), and AUC was 0.733 (0.708 in men, and 0.764 in women). Therefore, it may not be appropriate to apply the guidelines for diagnosing IFG since sensitivity and specificity were below 70%. For future studies retarding the cutoff value of HbA1c in predicting IFG, high sensitivity and specificity are expected if we segment the reference range of IFG.

• Economic and Environmental Geology
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• v.48 no.6
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• pp.431-449
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• 2015

The study area is located in the western part of the Precambrian stock type of Sancheong anorthosite complex, the Jirisan province of the Yeongnam massif, in the southern part of the Korean Peninsula. We perform a detailed field geological investigation on the Sancheong anorthosite complex, and report the characteristics of lithofacies, occurrences, foliations, and research formation process and its mechanism of the Sancheong anorthosite complex. The Sancheong anorthosite complex is classified into massive and foliation types of Sancheong anorthosite (SA), Fe-Ti ore body (FTO), and mafic granulite (MG). Foliations are developed in the Sancheong anorthosite complex except the massif type of SA. The foliation type of SA, FTO, MG foliations are magmatic foliations which were formed in a not fully congealed state of SA from a result of the flow of FTO and MG melts and the kinematic interaction of SA blocks, and were continuously produced in the comagmatic differentiation. The Sancheong anorthosite complex is formed as the following sequence: the massive type of SA (a primary fractional crystallization of parental magmas under high pressure)${\rightarrow}$ the foliation type of SA [a secondary fractional crystallization of the plagioclase-rich crystal mushes (anorthositic magmas) primarily differentiated from parental magmas under low pressure]${\rightarrow}$the FTO (an injection by filter pressing of the residual mafic magmas in the last differentiation stage of anorthositic magmas into the not fully congealed SA)${\rightarrow}$the MG (a solidification of the finally residual mafic magmas). It indicates that the massive and foliation types of SA, the FTO, and the MG were not formed from the intrusion and differentiation of magmas which were different from each other in genesis and age but from the multiple fractionation and polybaric crystallization of the coeval and cogenetic magma.