• Computers and Concrete
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• v.6 no.5
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• pp.391-401
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• 2009

This paper presents a study of the strength and chloride penetration of blended Portland cement mortar containing ground palm oil fuel ash (POA) and ground river sand (GS). Ordinary Portland cement (OPC) was partially replaced with POA and GS. Compressive strength, rapid chloride penetration test (RCPT) and chloride penetration depth of mortars were determined. The GS only asserted the packing effect and its incorporation reduced the strength and the resistance to chloride penetration of mortar. The POA asserted both packing and pozzolanic effects. The use of the blend of equal portion of POA and GS also produced high strength mortars, save cost and excellent resistance to chloride penetration owing to the synergic effect of the blend of POA and GS. For chloride depth, the mathematical model correlates well with the experimental results. The computer graphics of chloride depth of the ternary blended mortars are also constructed and can be used to aid the understanding and the proportioning of the blended system.

• Convergence Security Journal
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• v.7 no.1
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• pp.11-17
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• 2007

This paper related to implementing issue and performance measuring about blended mechanism between networking technology and security technology. We got more effectiveness in overall network security, when applying and composing amalgamated security mechanism between network technology and security technology. The blended method offers $8{\sim}10%$ effective result in network security than the isolated ways of applying relational two technologies. As a result, we suggest amalgamated security mechanism between network technology and security technology, and also, we propose the blended method as a model of more effective way.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.1
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• pp.64-71
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• 2005

In this paper we are investigating how ubiquitous revolution in knowledge society changes the education system. By the help of ubiquitous computing and networking techniques we estimates the configuration of e-teaming in the age of knowledge -based society, and we examines Education Model with e-teaming and ICT (Information and Communication Technology) at e-School. We also suggest the feasible design of the e-School and a Blended-learning scheme based on cooperative education as a way of teaching Education.

• Computers and Concrete
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• v.20 no.6
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• pp.627-634
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• 2017

Predicting the compressive strength of concrete is important to assess the load-carrying capacity of a structure. However, the use of blended cements to accrue the technical, economic and environmental benefits has increased the complexity of prediction models. Artificial Neural Networks (ANNs) have been used for predicting the compressive strength of ordinary Portland cement concrete, i.e., concrete produced without the addition of supplementary cementing materials. In this study, models to predict the compressive strength of blended cement concrete prepared with a natural pozzolan were developed using regression models and single- and 2-phase learning ANNs. Back-propagation (BP), Levenberg-Marquardt (LM) and Conjugate Gradient Descent (CGD) methods were used for training the ANNs. A 2-phase learning algorithm is proposed for the first time in this study for predictive modeling of the compressive strength of blended cement concrete. The output of these predictive models indicates that the use of a 2-phase learning algorithm will provide better results than the linear regression model or the traditional single-phase ANN models.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.3
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• pp.87-98
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• 2021

Due to the influence of COVID-19, many changes have been made in the education methods in universities. In respomse, this study intendsto present an efficient learning method by identifying the impact of professor images on learning immersion and the learning satisfaction of classes taught with blended learning for university students majoring in beauty at H University in Seoul. For final analysis, 232 of the 234 questionnaires administered from May 17, 2021 to June 2, 2021 were analyzed. For statistical analysis, SPSS 21.0 was utilized; frequency analysis was conducted to identify demographic characteristics, factor analysis was used to verify the research model, and regression analysis was conducted to verify the hypothesis. First, images of professors have been shown to affect learning immersion. Second, the professor image were shown to affect learning satisfaction. Third, education immersion has been shown to affect educational satisfaction. In order to overcome the limitations of online lectures in universities that suddenly began with onset of COVID-19, it is believed that students' satisfaction can be increased by applying blended learning as a way to improve the quality of classes.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.7
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• pp.637-646
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• 2010

A time-domain panel method based on the potential flow theory and the time-stepping method is developed to predict the steady/unsteady aerodynamic characteristics of FM07, which is the BWB (Blended-wing body) type MAV. In the aerodynamic analyses, we used two types of the initial model(Case I) and the improved model(Case II), which is moved the gravity center toward the rear and has larger aspect ratio. In the steady aerodynamic analyses, it is revealed that improved model has higher lift to drag ratio(L/D) and more stable pitch characteristic than those of the initial model. In the unsteady aerodynamic analyses for sudden acceleration motion similar to the launch phase of MAV, it seemed that there is a rapid increase of the lift coefficient after the launch and unsteady results are good agreed compare with steady results in just a few times. In the analysis for pitch oscillation motion, which is occurred at the cruise condition of the FM07, it shows that unsteady aerodynamic coefficients looped around steady results and the improved model has more sensitive aerodynamic characteristics.

• Journal of Digital Contents Society
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• v.13 no.4
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• pp.517-524
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• 2012

This paper deals with the design of teaching learning model for programming language education. Various courses related to programming language education have opened at the university having many academic majors. In the meantime, a variety of programming languages have been developed, many integrated development environments of programming language have also been developed for users to make a program easily. But it is difficult for many novice learners to learn programming language still, likewise it is difficult for many teachers to teach the introduction course of programming language. In this paper, we have designed a teaching learning model based on scholastic achievements and blended learning for programming language education. The teaching learning model designed in this study was applied to a course opened in the second semester of 2011. According to the course evaluation result, the teaching learning model for programming language has shown to be an effective for novice learner.

• Computers and Concrete
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• v.31 no.2
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• pp.111-121
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• 2023

The influence of material composition such as aggregate types, addition of supplementary cementitious materials as well as exposed temperature levels have significant impacts on concrete residual mechanical strength properties when exposed to elevated temperature. This study is based on data obtained from literature for fly ash blended concrete produced with natural and recycled concrete aggregates to efficiently develop prediction models for estimating its residual compressive strength after exposure to high temperatures. To achieve this, an extensive database that contains different mix proportions of fly ash blended concrete was gathered from published articles. The specific design variables considered were percentage replacement level of Recycled Concrete Aggregate (RCA) in the mix, fly ash content (FA), Water to Binder Ratio (W/B), and exposed Temperature level. Thereafter, a simplified mathematical equation for the prediction of concrete's residual compressive strength using Gene Expression Programming (GEP) was developed. The relative importance of each variable on the model outputs was also determined through global sensitivity analysis. The GEP model performance was validated using different statistical fitness formulas including R², MSE, RMSE, RAE, and MAE in which high R² values above 0.9 are obtained in both the training and validation phase. The low measured errors (e.g., mean square error and mean absolute error are in the range of 0.0160 - 0.0327 and 0.0912 - 0.1281 MPa, respectively) in the developed model also indicate high efficiency and accuracy of the model in predicting the residual compressive strength of fly ash blended concrete exposed to elevated temperatures.

• Journal of The Korean Association of Information Education
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• v.15 no.2
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• pp.179-188
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• 2011

The purpose of this thesis was to implement effective blended PBL(Problem-Based Learning) systems for information communication ethics education. The proposed systems, Online learning and face-to-face classes were systematically combined and Moodle is used for online learning platform. We proposed the use of wikis and blogs not just for creation of knowledge, but as active learning tool to support PBL. In the proposed system, learners used the web 2.0 as a open place to create new knowledge and experience various effects of PBL, such as (1) Improvement of problem solving ability, (2) Understanding of cooperative learning. The blended PBL systems with teaching and learning model were evaluated learners' level of satisfaction and educational achievement in the study of information communication ethics. The result shows that blended PBL learning method is more effective in cultivating consciousness of information communication ethics and showed more higher level of learners' satisfaction and educational achievement than the face-to-face PBL learning method.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.2
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• pp.145-153
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• 2022

Purpose : This study aimed to investigate the effects of blended learning on learning satisfaction in nursing students. Methods : This study was conducted with 160 current nursing students in the department of nursing at K university located in city B. All students included in the study understood the purpose of the study and provided informed consent to participate. Data were collected between May 3 and July 9, 2021 and analyzed using SPSS/WIN 22.0. The frequency, percentage, mean, and standard deviation were created, and t-test, ANOVA, and Scheffé test for post hoc analysis were performed. Correlations were analyzed using Pearson's correlation coefficient. The factors influencing learning satisfaction were analyzed using multiple regression. Results : Significant differences were observed for academic stress according to the online classes environmental satisfaction (F=4.10, p=.001), online classes experience (t=4.11, p=.001) and self-directed learning ability according to the grade (F=4.10, p=.001), online classes environmental satisfaction (t=4.11, p=.001). The academic stress of nursing students who experienced blended learning was significantly negatively correlated with self-directed learning ability (r=-.480, p<.001), and learning satisfaction (r=-.236, p<.001). self-directed learning ability showed a significant positive correlation with learning satisfaction (r=.524, p<.001). The regression model for the factors affecting the learning satisfaction of the subjects was statistically significant (F= 3.027, p<.001). The major influential factors of learning satisfaction were grade (𝛽=.154, p=.013), satisfaction with school life (𝛽=.168, p=.032), and satisfaction with non-contact learning environment (𝛽=-.141, p=.028). The explanatory power was 28 %. Conclusion : These results indicate that it is necessary to reduce academic stress and increase self-directed learning ability to enhance learning satisfaction in nursing students through blended learning. In addition, the development and operation of a tailored intervention program is required to help improve learning satisfaction.