• Journal of the Korea Institute of Building Construction
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• v.6 no.3 s.21
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• pp.99-105
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• 2006

In this paper, the estimation of compressive strength of concrete incorporating fly ash subjected to high temperature is discussed. Ordinary Portland cement and fly ash cement(30% of fly ash) were used, respectively. Water to binder ration ranging from 30% to 60% and curing temperature ranging from $20^{\circ}C{\sim}65^{\circ}C$ were also adopted for the experimental parameters. According to results, at the high temperature, FAC had higher strength development at early age than OPC concrete and it kept its high strength development at later age due to accelerated pozzolanic reaction subjected to high temperature. For strength estimation, Logistic model based on maturity equation and Carino model based on equivalent age were applied to verify the availability of estimation model. It shows that fair agreements between calculated values and measured values were obtained evaluating compressive strength with logistic curve. The application of logistic model at high temperature had remarkable deviations in the same maturity. Whereas, the application of Carino model showed good agreements between calculated values and measured ones regardless of type of cement and W/B. However, some correction factors should be considered to enhance the accuracy of strength estimation of concrete.

• Journal of Environmental Science International
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• v.16 no.3
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• pp.347-355
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• 2007

In this paper, estimation of the compressive strength of the concrete incorporating blast furnace slag subjected to high temperature was discussed. Ordinary Portland cement and blast furnace slag cement (BSC;30% of blast furnace slag) were used, respectively. Water to binder ratio ranging from 30% to 60% and curing temperature ranging from $20^{\circ}C{\sim}65^{\circ}C$ were also chosen for the experimental parameters, respectively. At the high temperature, BSC had higher strength development at early age than OPC concrete and it kept its high strength development at later age due to accelerated latent hydration reaction subjected to high temperature. For the strength estimation, the Logistic model based on maturity equation and the Carino model based on equivalent age were applied to verify the availability of estimation model. It was found that fair agreements between calculated values and measured values were obtained evaluating compressive strength with logistic curve. The application of logistic model at high temperature had remarkable deviations in the same maturity. Whereas, the application of Carino model showed good agreements between calculated values and measured ones regardless of type of cement and W/B. However, some correction factors should be considered to enhance the accuracy of strength estimation of concrete.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.141-148
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• 2020

This paper analyzes factors affecting the debt maturity structure of enterprises listed on the Vietnam stock market. The panel data of research sample includes 549 non-financial listed enterprises on the Vietnam stock market from 2009 to 2019. The Generalized Least Square (GLS) tool is employed to address econometric issues and to improve the accuracy of the regression coefficients. In this research, debt maturity structure is the dependent variable. Capital structures, fixed assets, liquidity, firm size, asset maturity, profitability, corporate income tax, gross domestic product, inflation rate, credit growth scale are independent variables in the study. The model results show, that among the factors affecting the structure of debt maturity, the capital structure, asset structure, and firm size have the highest estimation coefficients, which shows that capital structure, asset structure, and firm size plays an important role in the decision-making process of debt maturity structure. The empirical results show that there are differences in the impact of these factors on the debt maturity structures in state-owned enterprises and non-state enterprises listed on the Vietnam stock market. The findings of this article are useful for business administrators, helping business managers make the right financial decisions to determine the target debt maturity structure in enterprises.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.04a
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• pp.399-404
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• 2008

The objective of this study is to develop the predicting method of concrete strength when remove concrete form-work without making cement test piece at construction site. For this purpose, this study catches the Maturity Method by using RFID, the usability of which is now being emphasized at site, accumulates and record the strength data, which can be gained with the results of existing Maturity Method method that is accompanied with strength estimation study, in database, and finally proposes the system structure which can check the estimated strength by Maturity Method. The merits of this method by using of Maturity Method are as follows; More objective, precise, and rapid decision can be made to the concrete strength and about the maintaining period of concrete form and form support. More efficient control of integrated material management system can be possible. Architectural field example using RFID can be suggested more concretely. RFID applicability can be extended by using DB of material integration management system.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.785-793
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• 2022

In this study, tomato maturity was estimated based on deep learning for a harvesting robot. Tomato images were obtained using a RGB camera installed on a monitoring robot, which was developed previously, and the samples were cropped to 128 × 128 size images to generate a dataset for training the classification model. The classification model was constructed based on convolutional neural networks, and the mean-variance loss was used to learn implicitly the distribution of the data features by class. In the test stage, the tomato maturity was estimated as a continuous index, which has a range of 0 to 1, by calculating the expected class value. The results show that the F1-score of the classification was approximately 0.94, and the performance was similar to that of a deep learning-based classification task in the agriculture field. In addition, it was possible to estimate the distribution in each maturity stage. From the results, it was found that our approach can not only classify the discrete maturation stages of the tomatoes but also can estimate the continuous maturity.

• Journal of Animal Environmental Science
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• v.4 no.2
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• pp.183-191
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• 1998

This study was carried out to elucidate the correlation between Germination Index(G.I.) and CO2 emission for evaluation of the maturity of compost products. 13 compost samples was used for this experiment. The G.I. test was carried out on the basis of T-N 200ppm. As a result of this research, we found that CO2 emission method was good simple indicator for evaluation of maturity of compost materials, in spite of G.I. The obtain results are summarized as follows ; 1. The correlation value between the G.I. and the CO2 emission was R2 = 0.776. 2. The correlation value between EC(Electric Conductivity) and G.I. was R2 =0.7. 3. The equation calculated from G.I. and CO2 emission was G.I. = -16.7(InCO2) - 6.87. 4. From these results, we found the possibility of estimation for the value of G.I.(T-N 200ppm) from CO2 emission volume under specific condition.

• Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.350-356
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• 2022

This study aims to estimate the smallest size of mature individuals that can be exploited. Fish samples of Coryphaena hippurus were collected from Kalinaun fishermen's catches in the Molucca Sea. They were sexed, then the fork length (FL) and maturity stage were recorded. Results showed that C. hippurus in the Molucca Sea had a sex ratio of 1:1.94 (p < 0.05). Males had a length range of 499-831 mm FL and females were in the length range of 481-813 mm FL. Size at first maturity was estimated as 529 mm FL for males with a range of 475-588 mm FL and 405 mm FL for females. This study provided basic information for future management needs of the dolphinfish, especially in the Molucca Sea.

• The Journal of the Korea Contents Association
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• v.14 no.7
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• pp.386-394
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• 2014

Entertainment Industry, with high productivity of added value, is noticed as a major industry leading global economy. Thus the government has been constantly attempting to devise various plans for developing entertainment industry, but the plans are mostly come out according to currently faced issues rather than considering the whole industry interior interaction. We are mainly objective to find a ground for estimating the current entertainment industry status. For this, we borrowed the concept of 'maturity' from various capacity maturity estimation tools. We also analyzed Korean film industry as a representative entertainment industry case to find what and how government intervention has affected on the industry.

• 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.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.23-24
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• 2020

In this study, the concrete compressive strength estimation system Concrete IoT Management System (hereinafter referred to as CIMS) was developed, and CIMS was applied to domestic field structure slabs and wall concrete to check whether CIMS is practically available and to estimate the accuracy of the initial strength estimation of concrete. As a result, it shows a very high correlation when the compressive strength of the specimen for structural management is compared with the estimated strength of CIMS in terms of integrated temperature, and it is expected to be gradually applied to domestic construction sites in the future.