• Computers and Concrete
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• v.31 no.3
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• pp.241-252
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• 2023

Corrosion of rebar is one of the major deteriorating mechanisms that affect the durability of reinforced concrete (RC) structures. The increase in CO₂ concentration in the atmosphere leads to early carbonation and deterioration due to corrosion in RC structures. In the present study, an attempt has been made to modify the existing carbonation depth prediction empirical model. The modified empirical model is verified from the carbonation data collected from selected RC structures of CSIR-SERC campus, Chennai and carbonation data available from the reported literature on in-situ RC structures. Attempt also made to study the carbonation depth in the laboratory specimens using oxygen permeability index (OPI) test. The carbonation depth measured from RC structures and laboratory specimens are compared with estimated carbonation depth obtained from OPI test data. The modified empirical model shows good correlation with measured carbonation depth from the identified RC structures and the reported RC structures from the literature. The carbonation depth estimated from OPI values for both in-situ and laboratory specimens show lesser percentage of error compared to measured carbonation depth. From the present investigation it can be said that the OPI test is the suitable test method for both new and existing RC structures and laboratory RC specimens.

• Journal of Korean Clinical Nursing Research
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• v.24 no.3
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• pp.324-335
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• 2018

Purpose: The purpose of this study was to propose a revised Clinical Ladder System(CLS) Model for nurses based on the evaluation of clinical competence and professional activities of nurses working in general hospitals. Methods: Data were collected between September 10 and October 30, 2017. Participants were 50 head nurses from 10 general hospitals with over 400 beds located in Seoul City and Gyeonggi Province. Each head nurse evaluated clinical competence, qualifications, and professional activities of 5 staff nurses at each of the 5 levels of CLS in her unit. The total number of the nurses evaluated was 245. Data were analyzed with descriptive statistics and t-test, one-way ANOVA, and $Scheff{\acute{e}}$. Results: Over 80% of the nurses were university graduates. As the CLS levels increased, clinical competence, qualifications, and professional activities also increased significantly. Education material development and quality improvement activities were carried out by nurses from level 2, research and evidence based practice activities were carried out from level 3, and nurses at level 4 or 5 participated in most of the professional activities as leaders. Conclusion: In order to retain excellent nurses in general hospitals, recognizing and rewarding nurses according to the revised model of the CLS are recommended.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.185-186
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• 2015

The Standard penetration test determines the type of soil according to soil bearing capacity, and this classifies the subsoil into many layers. Construction project managers are willing to know the depth of the present types of subsoil on site in order to make plans on earthwork stage during excavation. However the standard penetration test may not provide accurate information on subsoil type due to incorrect spacing. To solve this problem, this study propose a conceptual algorithm for determining the spacing of standard penetration test spots to essentially tests relevant locations on which to be applied the standard penetration test. This provides the acquirement of the accurate layered model volume of earthwork revised into geological columnar section. This algorithm will determine the appropriate standard penetration test spots spacing on a given size of site to optimize the accuracy of the earthwork volume, time and cost.

• Journal of Korean Academy of Nursing
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• v.40 no.1
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• pp.127-138
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• 2010

Purpose: This study was designed to develop and test a structural model for children's adaptation in divorced families. The hypothetical model was constructed based on the Family Resilience Model by McCubbin and McCubbin. Methods: Data were collected using self-report questionnaires from 219 children (3-6th grade) in divorced families. The children attended one of 22 community agencies, 8 after-school programs, 3 elementary schools in three cities in South Korea. The collected data were analyzed using LISREL program to test the hypothetical model. Results: The modified model was constructed by deleting four paths in accordance with the statistical and theoretical criteria. Compared to the hypothetical model, the revised one had a better fit to the data. Self-esteem, and beliefs about parental divorce had direct effects, and family communication and internal control had indirect effects on children's adaptation in divorced families. These variables explained 56% of the variance in children's adaptation. Conclusion: The modified model was supported by empirical data. This model could be applied to family nursing interventions with divorced families or any other suffering family transition. When working with children experiencing parental divorce, it is important for nurses to enhance children's self-esteem, family communication and to decrease children's negative beliefs about parental divorce to help in their adaptation.

• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.3
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• pp.111-129
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• 1994

In this study, we develope a revised model as well as application of decision problem under ambiguity based on the subjectively weighted linear utility medel. Bayes'rule is used when there are ambiguous probabilities on a decision problem and test information is available. A procedure for assessing the ambiguity aversion function is also presented. Decision problem of chemical corporation is used for an illustration of the application of the subjectively weighted linear utility model using Bayesian approach. We present the optimal decisiond using newly developed model. We also perform the sensitivity analysis to assure ourselves about the conclusion we obtianed on degree of ambiguity aversion due to characterize parameter of subjectively weighted linear utility model.

• Journal of Gifted/Talented Education
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• v.25 no.6
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• pp.951-970
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• 2015

The purpose of this study is to explore related variables to influence gifted college students' career conviction and to propose a structural model. For the study, 292 college students who have experienced university affiliated gifted education program during their school days. Rational decision making test, intrinsic motivation test, career decision efficacy test, and major conviction test were utilized. SPSS program and AMOS were used for statistical analyses. The results are summarized as follows. The fit of measurement model was found to be TLI=.923, CFI=.951, RMSEA=.077, indicating most of the fit indexes were acceptable. The path to career conviction from rational decision making and intrinsic motivation was found to be insignificant, suggesting a revised model. The fit of final revised measurement model was found to be TLI =.926, CFI=.951, RMSEA=.075, indicating the model was acceptable. Interestingly, the career decision efficacy was found to be the complete mediator among the rational decision making, intrinsic motivation, and career conviction. The results of the study showed that career decision efficacy has a very important role in gifted college students'career choice and decision. Implication of the study related to the career education and counseling has been discussed in depth.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.5 s.149
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• pp.529-537
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• 2006

International Maritime Organization (IMO) is planning to include the Alternative Assessment of the Weather Criterion in the new Intact Stability (IS) Code to be revised. In this study, the procedure of the model test in the Interim Guidelines was reviewed by carrying out the model test and analyzing the test results. For this purpose, RO/RO passenger ship whose ratios of breadth to draft and the height of weight to draft were above 3.5 and above 0.6 respectively was selected as a test ship. Drifting test and motion test in regular waves were performed to estimate the hydrodynamic heeling lever and roll-back angle. Motion tests in waves were carried out in the three wave steepness conditions to measure roll-back angle and examine the feasibility of so called, the Three-step method. Using the test data, satisfaction of the Weather Criterion was assessed for the test ship by using the alternative method and compared with the current method.

• The Journal of the Korea Contents Association
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• v.15 no.3
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• pp.290-302
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• 2015

The study purpose was to test the validity and reliability of the Korean version of the Revised Stress Appraisal Measure (RSAM) to assess stress appraisal in undergraduate students. Internal consistency reliability, construct and criterion validity were calculated using IBM SPSS Statistics 21 and AMOS 21 program. Survey data were collected from a convenience sample of 296 undergraduate students enrolled in five universities in G city and C area, South Korea. The Korean version of RSAM categorized into 5 factors explaining 68.4% of the total variance. The model of five subscales was validated by confirmatory factor analysis (p<.001, Goodness of Fit Index, Adjusted Goodness of Fit Index, Normed Fit Index, Comparative Fit Index >.08, Root Mean Square Error of Approximation=.056). In criterion validity, the scores for the scale were significantly correlated with the Perceived Stress Scale-Korean. Cronbach's alpha coefficient for the 19 items was .73~.89. The Korean RSAM showed satisfactory construct and criterion validity and reliability. Thus it may be an appropriate instrument for measuring stress appraisal in Korean university students.

• Journal of Educational Research in Mathematics
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• v.14 no.1
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• pp.71-88
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• 2004

The purpose of this study was to examine particular variables that play a significant role in the difficulty of math test items in College Scholastic Ability Test (CSAT). The study also aimed to develop a model of measuring the item difficulty. Variables correlated to item difficulty were drawn from the review of the related literature and the analysis of the content and difficulty of the past test items of CSAT. The first instrument was designed by using the correlated variables. According to the results of correlation analysis, the second instrument was made by deleting the variables which showed relatively low correlation with item difficulty and by refining some variables. Several models were proposed by using the revised instrument. The comparison of the R square and cross validity of each model reveals that integrated regression model was the most stable and accurate among the proposed models. The study also showed that statistically significant predictors were choice format, content domain, behavior domain, and the degree of item familiarity in the order of proportion of variance accounted by the predictors. Despite the limited scope of the present research, it can be suggested that its findings provide useful insights into predicting math test item difficulty.

• Educational Technology International
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• v.17 no.1
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• pp.1-37
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• 2016

The purpose of this study was to develop a MOOC design model that would improve the current practice of MOOC development in Korea by specifying easy-to-use course development procedures and guiding strategies. Following Richey and Klein (2007)'s conceptual model development procedure, the first step was to perform critical review of relevant literature and observe typical MOOC development processes. As a result, the initial model was developed. The second step was to conduct the expert review with five educational technology and MOOC researchers to secure the internal validity of the model. Based on the experts' suggestions, the model was revised and once again reviewed by the same experts. This process resulted in the development of the 2^nd version of model. The third step was to carry out external validation research in order to test the effectiveness, efficiency, and usability of the model. A basic model may be confirmed or corrected based on examination of its results. Consequently, the model was elaborated as the final model. In the final model, 6 procedural phases and 9 specific steps were included. The six procedural phases are: Analysis (1st Iteration), Design, Development (Course Development), Implementation, Evaluation, and Analysis (2nd Iteration), a slight variation of ADDIE model. The specific steps include: 1) Goal Setting, 2) Environment Analysis, 3) Content Design, 4) Style Design, 5) Course Development, 6) Implementation Plan, 7) Course Implementation, 8) Summative Evaluation, and 9) Need Reflection. The study concluded with suggestions for further research and application of the MOOC design model.