• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.143-150
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• 1997

The maturity concept was adopted to predict the strength of concrete, which was subjected to same temperature conditions and variable curing conditions. Penetration test and compressive test were conducted to measure the initial and final setting time and the compressible strength of concrete specimen, respectively. Also, the temperature and time were recorded at some intervals of time for calculating the maturity. The initial and final setting were delayed as the w/c ratio increased and curing temperature decreased. The activating energy decreased as the w/c ratio increased. The relationships at the relative strength and the maturity were proposed at different w/c ratio for the same temperature curing condition, and these were applied for the variable curing conditions. The results indicated that the difference between the strength of the proposed and the specimen was big at 1 days's age but quite similar after 3 day's age.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.5-6
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• 2016

When concrete exposed to low temperatures, the free water in the concrete is freeze. If the pressure developed exceeds the tensile strength of the concrete, the cavity will dilate and rupture. It cause expansion and cracking, scaling and crumbling of the concrete. In this study, to prevent such damage, five different types of form were used. Concrete was poured into each form, cured for 7 days at temperature of -10℃. To measure the temperature history, two thermocouples were installed on each of the inside and outside. And to measure the compressive strength, collected core from each form. The maturity is formed by temperature history. The maturity and the compressive strength has a correlation.

• Korean Journal of Human Ecology
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• v.19 no.1
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• pp.215-225
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• 2010

This study had the purpose of presenting a residential environment solution as a desirable educational environment for middle school students to grow soundly and to achieve proper self-realization while providing basic materials to build up a suitable residential environment by comparing and analyzing what relationships exist between different home backgrounds, residential environments and middle school students' social maturity. This research was conducted from Feb. 11, 2008 to Feb. 13, 2008. The subject of this research was 601 students in 3 middle schools located in Gyunggi-do. The data analyzed used the SPSS 11.5 version. The summary of this study's results is as follows. First, in terms of home background, the higher the parents' educational background and social and economic position, the greater the students' social maturity. Second, in terms of home environment, the more spacious the living space, the better the water and sewage system and rest room, the more convenient the air conditioner and kitchen system, the better the lighting, ventilation, soundproofness, insulation, the less the danger in relation to fire, crime, traffic accidents, disaster, the greater the students' social maturity. Third, in terms of the home environment related to the correlation between the residential environment and social maturity, all areas such as housing facilities, housing structural environment and housing safety showed static correlations and proved that the residential environment has an important influence on social maturity. Accordingly, in order to build up an ideal residential environment, we should make efforts to expand and improve better facilities at home considering privacy, lighting, ventilation, soundproofness, heating etc. and remove unsound factors that obstruct students social maturity and build up clean and safe residential environment with good relations with their neighbors.

• Journal of Families and Better Life
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• v.30 no.4
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• pp.77-87
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• 2012

The purpose of this study is to analyze the effects of social support and, career decision-making self-efficacy on career maturity of adolescents of different gender and grades. Further, it aims to provide basic information for career maturity to create career educational program for adolescents. The participants of the study were 447 middle and high school students who were selected from second grade of five schools in Daegu. All participants were tested on social support, career decision-making self-efficacy and career maturity scale. The results were analyzed using two-way ANOVA, Pearson's Correlation Analysis, Regression Analysis with SPSS 18.0. The results of the present research are summarized as follows: first, the results of the ANOVA subscales revealed that there were significant gender and grade main effects and interaction effects of social support, career decision-making self-efficacy and career maturity. Second, the results of the correlation analysis among of the social support, career decision-making self-efficacy and career maturity showed a positive and negative correlation. Third, in terms of the influence of social support, career decision-making self-efficacy had a significant meaningful influence on career maturity. The results of this study can be used as a fundamental reference in career counseling at school for enhancing adolescent's career development and success.

• Journal of Families and Better Life
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• v.31 no.5
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• pp.19-32
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• 2013

The purpose of this study was to identify the influences of psychological independence(functional independence and emotional independence) and career decision-making self-efficacy(self-estimation, career goal, occupational-knowledge, and problem solving) on career maturity(preparation, objective, decisiveness, and certainty) among adolescents. The subjects were 447 students in the second grade of middle school and high school in D. The questionnaire consist of measures of psychological independence, career decision-making self-efficacy, and career maturity. The data were analysed with factor analysis, Cronbach's ${\alpha}$, t-test, ANOVA, correlation and multiple regression by using the SPSS(SPSS/WIN 19.0) program. The major results were as follows. First, adolescents' the career maturity was significantly different depending on the socio-demographic variables. Second, it was shown that middle and high school students have a statically relation, in a relation among psychological independence, career decision-making self-efficacy, and career maturity. Third, it was found that psychological independence and career decision-making self-efficacy gave statistically meaningful influence on the career maturity of adolescents. This study is significant in that it suggests a plan for improving career maturity, and provides a basic material to improve one's active role in their parents. In addition, the results of this study can be used as a fundamental reference in career development programs and career-counseling centers at schools for enhancing adolescents' career development and success.

• Korean Journal of Agricultural Science
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• v.49 no.1
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• pp.129-136
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• 2022

In this study, we aimed to develop a maturity classification model for tomatoes using hyperspectral imaging in the range of 400 - 1,000 nm. Fifty-seven tomatoes harvested in August and November of 2021 were used as the sample set, and hyperspectral data was extracted from the surfaces of these tomatoes. A combined method of SNV (standard normal variate) and SG (Savitzky-Golay) methods was used for the pre-processing of the hyperspectral data. In addition, the hyperspectral data were analyzed for all maturity stages and considering bandwidths with different FWHM (full width at half maximum) values of 2, 25, and 50 nm. The PCA (principal component analysis) method was used to analyze the principal components related to maturity stages for the tomatoes. As a result, 500 - 550 nm and 650 - 700 nm bands were found to be related to the maturity stages of tomatoes. In addition, PC1 and PC2 explained approximately 97% of the variance at all FWHM conditions and thus were used as input data for classification model training based on the SVM (support vector machine). The SVM models were able to classify tomato maturity into five stages (Green, Turning, Pink, Light red, and Red) with over 95% accuracy regardless of the FWHM condition. Therefore, it was considered that hyperspectral data with 50 nm FWHM and SVM is feasible for use in the classification of tomato maturity into five stages.

• Journal of Distribution Science
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• v.11 no.2
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• pp.5-10
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• 2013

Purpose - The current research examines the effect of life cycle stages on capital structure of listed companies in Tehran Stock Exchange. Research design, data, methodology - By aid of 685 year-company data, which collected from financial statements of companies during 2006-2012, first, the companies, are classified into three groups including companies in growth, maturity and decline stages. After removing the companies, which were not in accordance with life cycle model, 86 companies were selected to test two main hypotheses of the research. Results - The results show that the capital structure of the sample companies is different in various life cycle stages. More investigation by LSD test also revealed that the total debt to total assets ratio means of the companies in growth stages were significantly different from those companies in maturity stages and those in growth stages had high level of debt to assets ratio. Conclusions - The result showed the average amount of the working capital for companies in three stages are significantly different and due to high level of operation of the companies in maturity and decline stages, these companies held high amount of working capital than those in the growth stages.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1228-1233
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• 1999

A study was conducted on four maize cultivars to determine the dry matter and fibre digestibility as influenced by advancing plant age. Samples of maize cultivars Akbar, Neelum, UM-81 and IZ-31 were harvested at weekly intervals/ growth stages. The samples of morphological fractions such as leaf and stem were also collected at various growth stages. Whole mixed fodder and different fractions of maize plant were analysed for their chemical composition and in vitro digestibility. The results showed that in vitro dry matter digestibility (IVDMD) of whole maize plant, leaf and stem decreased significantly with advancing stage of maturity. Digestibility of NDF, ADF, hemicellulose and cellulose decreased significantly in all plant parts with advancing plant age/growth stages. Maximum values for the digestibility of dry matter and various cell wall constituents were observed in leaf, followed by whole plant and stem fractions. Cultivars were observed to have significant effect of IVDMD and digestibility of NDF, ADF and cellulose in all plant fractions. The results indicated that digestibility of maize fodder was affected by stage of maturity and cultivars. However, maturity had a greater effect on digestibility in all plant fractions than did cultivars. Dry matter contents were found to be significantly and negatively correlated with IVDMD of whole plant and its leaf and stem fractions. Based on correlations, regression equations were computed to predict IVDMD.

• International Journal of Concrete Structures and Materials
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• v.10 no.1
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• pp.47-60
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• 2016

The objective of this study was to evaluate the capability of different strength-maturity models to account for the effect of the hydration heat on the in-place strength development of high-strength concrete specifically developed for nuclear facility structures under various ambient curing temperatures. To simulate the primary containment-vessel of a nuclear reactor, three 1200-mm-thick wall specimens were prepared and stored under isothermal conditions of approximately $5^{\circ}C$ (cold temperature), $20^{\circ}C$ (reference temperature), and $35^{\circ}C$ (hot temperature). The in situ compressive strengths of the mock-up walls were measured using cores drilled from the walls and compared with strengths estimated from various strength-maturity models considering the internal temperature rise owing to the hydration heat. The test results showed the initial apparent activation energies at the hardening phase were approximately 2 times higher than the apparent activation energies until the final setting. The differences between core strengths and field-cured cylinder strengths became more notable at early ages and with the decrease in the ambient curing temperature. The strength-maturity model proposed by Yang provides better reliability in estimating in situ strength of concrete than that of Kim et al. and Pinto and Schindler.

• The Journal of Information Systems
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• v.7 no.1
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• pp.77-98
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• 1998

Electronic Data Interchange(EDI) is a relatively new technique around the world and enables the firm more competitive because of transmitting computer-generated documents directly to a firm's trading partner's computer across a telecommunication network. This study investigates the relationship among the organizational characteristics and information systems(IS) maturity, and the extent of internal and external diffusion of Electronic Data Interchange (EDI) in Korean firms. The data for this study were collected from 131 firms that have implemented EDI. The results of t-test show that subgroups classified by industry, the extent of decentralization and formalization, and IS maturity, except the size of organization, are not different in the extent EDI diffusion. Also, the results of multiple regression analysis show that the size of organization is the major predictor of internal diffusion, and IS maturity and the size of organization are the major predictors in external diffusion of EDI. This study implies that the size of organization among organization characteristics and IS maturity should be considered as important variables for the diffusion of EDI system.