• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.39-42
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• 2002

Cloride attack of concrete is one of the important causes of corrosion of reinforcing steel in concrete with carbonation and frost damage. In this paper, the effect of fly-ash on the cloride attack were investigated by varying water binder ratio and fly-ash contents according to the chloride ion penetrationa test. (ASTM C 1202-94) The principal conclusions from this research were as follows: 1) The compressive strength of concrete at large ages, depends more on $C_2$S contents of base cement than fly-ash contents. 2) On the other hand, the chloride ion penetration of concrete at large ages, principally depends on fly-ash contents and the influence of type of base cement is insignificant.

• Journal of Korean Academy of Nursing
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• v.36 no.1
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• pp.45-54
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• 2006

Purpose: The purpose of this study was to explore Korean mothers' experiences of caregiving for their adult children with schizophrenia. Method: A iterative descriptive qualitative research design was used to understand and explain the caregiving experience from the perspective of mothers. The data were collected by individual in-depth interviews and one focus group interview from 11 mothers. The ages of the participants ranged from 50 to 60 years old and the ages of their sick children ranged from late 20s to early 40s, Results: Three major themes were identified from qualitative thematic analysis: (a) 'emotional debris from the disease,' (b) 'the disease that makes mothers dumb' (c) 'space of rational reason,' Conclusions: This study would provide health care professionals insights in establishing intervention for mothers by deeply understanding the process of recognition and acceptance of their children with schizophrenia.

• Proceedings of the Speleological Society Conference
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• 1993.07a
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• pp.163-172
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• 1993

Cheju island is situated at about 90km south of southern most tip of the Korean peninsula. Its shape is an ellips with size of 80$\times$40$km^2$, and it is characterized by a symmetrical form whose peak is Mt. Halla (1950m). Major chemical composition of the rock samples from Manjang gul cave is determined by XRF using the fundamental parameter method consisting of fully auto quantitative analysis, semi quantitative analysis (order estimation) and group quantitative analysis. Judging from chemical composition ($SiO_2 = 53.07Wt% Fe_2 O_3=11.34Wt%, MgO=6.48Wt%, Na_2 O=3.07Wt%, K_2 O=1.05Wt%$), this rocks may belong to non alkalic basalt. K-Ar ages of two rocks samples from the Manjang gul cave are also determined. The discrepancy of K-Ar ages is found. They are 0.03Ma and 0.42Ma, respectively. This paper describes some problems experienced in dating young volcanic rocks and then discusses chemical composition, X-ray fluorescence analysis and the age of the formation of a lava tunnel such as Manjang gul cave in cheju Island.

• The Research Journal of the Costume Culture
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• v.3 no.2
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• pp.293-306
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• 1995

The purpose of this study is to analysis children's measurement and to provide the fundamental information for he clothing design which can reflect the characteristic of their bodies. An anthropometric database used for this study was the 1992 national anthropomatric survey of Koreans. The results obtained are as follows; (1) Children showed the significant difference of their growth in accordance with the increase of their ages. There were also the difference between body and girls. Height, length of items grew most promthy. For example; boys from 10 to 11 and girls from 10 to 11 again their height mostly. (2) In character of body proportion, significant difference were found in accordance with their ages and sex. However, in the items of height, length noticeable changes of proportion could not be found because there were hardly any actual difference of size means while girth items appeared differently. (3) There were significant factors from the result of factor analysis of body dimension. The fist factor ; grith, depth, breath. The second factor ; height, length. (4) We can class three groups with the results of cluster analysis of body dimension.

• The korean journal of orthodontics
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• v.13 no.2
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• pp.201-204
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• 1983

To study the calcification of second molars in Class I malocclusion with normal craniofacial structure, the author examined cephalograms, orthopantomograms, periapical films of 538 children from 7 y 0 m to 15y 11m old who had Class I malocclusion with normal craniofacial structure, and observed the calcification stage of upper and lower second molars. The results are as follows. 1. The mean ages of crown completion of upper and lower second molars are $8.82{\pm}1.14,\;8.72{\pm}0.75$ in boys, and $8.60{\pm}1.46,\;8.22{\pm}0.92$ in girls. 2. The mean ages of root completion of upper and lower second molars are $14.25{\pm}1.46,\;14.15{\pm}0.83$ in boys, and $14.12{\pm}0.93,\;14.15{\pm}0.83$ in girls. 3. There are no difference between the calcification stages of upper second molars and those of lower second molars in both sexes.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.629-634
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• 2001

This study is to characterize the material property of early age high performance concrete emphasizing compressive strength using nondestructive testing methods. Three high performance concrete slabs of 600, 850 and 1100kg/$cm^{2}$ compressive strengths were prepared together with cylinders from same batches. Cylinder tests were peformed at the ages of 7, 14, 21 and 28 days after pouring. Using the impact echo method, the compression wave velocities were obtained based on different high performance concrete ages and compressive strengths. The equation to obtain the compressive strengths of high performance concrete has been developed using the obtained compression wave velocities. Using the SASW (spectral analysis of surface wave) method, the equation have also been developed to obtain the compressive strengths of high performance concrete based on the surface wave velocities.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.12a
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• pp.124-126
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• 2005

Aquatic ecotoxicity of bisphenol A, a well known endocrine disrupter in mammals, was studied using lab. reared Daphnia magna as a test organism. The static acute 48h $LC_{50}$ of bisphenol A was 12.9mg/L and 110-hr $LC_{50}$ values of bisphenol A for daphnid embryos of different ages after deposition into the brood chamber increase with ages in the range of 1.55mg/L-8.91mg/L. Bisphenol A showed the ability to inhibit embryonic development. The lethal response and developmental inhibition all showed good concentration-response relationship.

• Journal of the Korea Furniture Society
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• v.21 no.1
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• pp.40-53
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• 2010

The purpose of this study was verified the effect of analyzed emotional factors and compare with competed design proposals of G and D public exhibition to plan the public exhibition applied emotional marketing which strengthen the effect with touching the emotion. The results are first, public consumer preferred to experience 5 senses and gives a positive effect, second, preference according to factor of scene gives differences by ages, but various ages preferred to experience the factor of scene, third the result of analyze the relation between preference of scene and 3 groups of 5 senses, which is high, middle, and low preferred had significant relation, and fourth, public consumer preferred to several levels of exhibition than only one level, the space preferred was 'experiencing' space.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.2
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• pp.188-199
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• 2003

This study intended to analyze the differences in (general & apparel) color preference and possession of apparel color preference(POA) by influential factors(fashion involvement, age, body-size and body- cathexis). We collected data from 303 females in the ages of 20's and 40's living in Seoul. The results were as follows; As a result of factor analysis, the fashion involvement was categorized into three aspects: coordinating fashion involvement, opinion-leading fashion involvement, and innovating fashion involve ment. There were significant differences among fashion involvement groups in the color preference and POA. Also the significant differences in color preferences and POA by ages and body-size were found. But in the analysis based on body-cathexis, no noticeable variance between different groups were found.

• Asian Journal of Innovation and Policy
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• v.3 no.2
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• pp.172-192
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• 2014

This study aims to analyze the valuation of technology firms in the stock market to answer how before-market entities should be valuated. This study analyzes 230 market reports of 2012 for technology firms in the KOSDAQ under several hypotheses. The results are as follows: 90% used the 3 multiples methods consisting of PER multiples with 80%, PBR multiples 8.7% and EBITDA multiples 1.7%. The average of PER multiples was 15 with the range of 6.9 to 83. That of PBR multiples is 2.27. Forecasting for cash flow is not applied over 4 years, but mainly 2-3 years. The accuracy of forecasting was 18.8%, 34.4% and 8% according to the different definitions. No differences were found in the accuracy of forecasting between valuation methods, between the industries having more intangible assets and the industries having less, and between startups and general companies and between ages and listed ages.