• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.2
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• pp.177-183
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• 1999

The major object of this study is to investigate experimentally the experimental equation by the non-destructive testing methods of ultrasonic pulse velocity, rebound number, combined method of ultrasonic pulse velocity and rebound number, maturity which are applicable to the evaluation of compressive strength of concrete at early ages. Also test result of mix are statistically analyzed to infer the correlation coefficient between the maturity and the compressive strength of concrete. The results show good application of Logistic curve for estimating strength development under various curing temperature. The relation between ultrasonic pulse velocity, rebound number, combined method of ultrasonic pulse velocity and rebound number and compressive strength of concrete have low correlation coefficient, but maturity method show good correlation coefficient.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.281-286
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• 1998

The aim of this study is to compare the development of compressive strength of high-Flowing concrete with maturity and to investigate the applicability of strength prediction models of concrete. An experiment was attempted on the high-flowing concrete mixes using Ordinary portland cement, High belite cement, Blast furance slage cement and replaced Fly-ash of 30% by weight of Ordinary portland cement, the water-binder ratios of mixes being 0.35 and the curing temperatures being 30, 20, 10, 5$^{\circ}C$. Test results of mixes are statistically analyzed to infer the correlation coefficient between the maturity and the compressive strength of high-flowing concrete.

• Journal of the Korean Society of Systems Engineering
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• v.7 no.1
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• pp.9-21
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• 2011

Assuming that the Capability Maturity Model Integration for Development v1.2 (CMMI) could be applied to an organization more effectively if the content similarities among practices were improved in terms of structure and composition, this paper presents the analysis of the correlations between the CMMI Specific Practices (SP) and Generic Practices (GP) for the Maturity Level 2 and 3 Process Areas using the Chi-square independence test. According to the analysis, a 22.2% correlation was observed. To minimize the problem of repeatedly applying similarities, 6 GPs that are highly correlated with the SPs were grouped together. Then, three different improvement plans: 1) development of a standard template-based project plan, 2) establishment of a configuration management system based on open source software to control work products and leverage experience, and 3) establishment of project assurance through an independent quality assurance-based organization and intensive review by higher-level management - were defined.

• Magazine of the Korea Concrete Institute
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• v.8 no.3
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• pp.197-207
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• 1996

Maturity is expressed as the integral of time and temperature of concrete above a datum temperature. The maturity concept proposes that concrete of the same mix at the same maturity has the same strength, whatever combination of temperature and time makes up that maturity. In this study, the Nurse-Saul function which was proposed to account for the effects of temperature and time on strength developrnent is used in computing maturity. After existing various functions are considered to relate concrete strength to the maturity value, new strength-maturity function is proposed. Tests ;ire conducted in order to determine d datum temperature and compare prechction value with measured concrete strength. The constants in proposed prediction equation are determined from test results, and the equation is adopted to predict the strength of slab. The slab was cast in the laboratory from the same batch of mold, and cores are cut from slab in order to estimate the actual strength. These values are used to compare with predicted value. The present study allows more realistic determination of early-age strength of concrete and can be efficiently used to control the quality in actual construction.

• 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.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.4
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• pp.1076-1088
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• 2016

This study was to validate the WSBS_PECT (Workplace Spirituality Belief Scale for Prospective Early Childhood Teacher) using discriminant analysis on prospective early childhood teachers' happiness and career maturity. The data from 523 prospective early childhood teachers were analyzed statistically through t-test and binary logistic regression model. The results indicated that 1) the higher group in workplace spirituality belief significantly gets more scores of happiness and career maturity than the lower group, 2) 1 factors of the WSBS_PECT has discriminant power on prospective early childhood teachers' happiness, and 3) 2 factors ('meaning for life' and 'belief on calling for ECE teacher job') of the WSBS_PECT are effective to discriminate prospective early childhood teachers' career maturity. Further statistical works are supplementary needed to validate the WSBS_PECT and to increase its' feasibility.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.555-565
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• 2018

This study was conducted to investigate factors influencing career maturity in nursing students. A convenience sample of 230 nursing student was selected from S city, between 20 October and 10 November 2017. Data were collected using a structured questionnaire and analyzed using descriptive statistics, t-test, one-way ANOVA, Pearson's correlation, and multiple regression analysis with the SPSS/WIN 21.0 program. Factors that influenced career maturity included gender(t=2.117, p=.035), age(t=-2.572, p=.011), grade(F=4.716, p=.010), education at the time of admission(t=-2.695, p=.008) and perceived academic achievement(F=11.127, p<.001). Career maturity showed a positive correlation with career decision-making self-efficacy(r=.585, p<.001) and problem solving ability(r=.407, p <.001), but a negative correlation with job-seeking stress(r=-.424, p<.001). Regression analysis revealed that significant factors influencing career maturity were career decision-making self-efficacy, problem solving ability and job-seeking stress. This regression model explained 42.8% of the variance in the career maturity. Based on these findings, it is necessary to develop and test programs to ensure an improvement in career decision-making self-efficacy, problem solving ability and job-seeking stress among nursing students to increase their career maturity.

• Journal of dental hygiene science
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• v.21 no.2
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• pp.86-95
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• 2021

Background: This study aimed to investigate the effects of department satisfaction and career maturity on the perceived health status, relationship, and self-efficacy of dental hygiene college students based on Alderfer's existence-relationship-growth theory. Methods: We obtained convenience samples of dental hygiene students in Daejeon and Chungnam areas; 241 questionnaires were collected from 250 persons considering the dropout rate and used for the final analysis except for 9 careless responses. The differences in perceived health status, relationship, self-efficacy, department satisfaction, and career maturity according to general characteristics were analyzed using a t-test, one-way analysis of variance and Pearson's correlation coefficients. Moreover, structural equation modeling was performed to confirm the variables. GFI, AGFI,CFI, RMR, RMSEA, TLI, and NFI indices were calculated to verify the fitness of the path model. Results: There were significant differences in self-efficacy, department satisfaction, career maturity according to grade, and significant differences in academic performance for all variables except relationship. The school system also had a significant effect on department satisfaction. Perceived health status, relationship, self-efficacy, department satisfaction, and career maturity demonstrated statistically significant positive correlations (p<0.05). The factors affecting department satisfaction were relationship and self-efficacy. The indirect and total effects of perceived health status and relationship on career maturity were not statistically significant; however, the indirect and total effects of self-efficacy on career maturity were statistically significant. Conclusion: It is necessary to develop teaching methods according to student management plans for dental hygiene by comprehensively perceived health status, relationship, and self-efficacy affecting department satisfaction and career maturity.

• 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.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.307-309
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• 2005

빠른 산업 발전 속에서 조직과 시스템이 복잡하고 대형화되면서 소프트웨어 품질을 향상시키고 그들의 신뢰성을 측정하기 위한 성숙도 모델들이 개발되었다. 그 중에서도 CMM와 이를 발전시킨 CMMI는 많은 조직에서 적용하기 위해 노력을 기울이고 있다. 하지만 두 모델들은 테스트 속성과 테스트 프로세스에 대한 언급이 부족하다. 본 논문에서는 모든 영역을 고려한 새로운 모델을 만들기 보다는 테스트 중심으로 개발된 TMM을 사용하여 CMMI과의 매핑을 통해 소프트웨어 조직의 생산품질과 신뢰성을 향상 시키는 방법을 제안한다. 논문에서는 CMMI 단점과 이를 보완하는 방법을 제안하고 이를 위해 TMM과 CMMI의 매핑전략에 언급한다. 이를 통해 기대되는 효과를 제시한다.