• Steel and Composite Structures
• /
• v.34 no.6
• /
• pp.837-851
• /
• 2020

This study aims to examine the interface shear behavior between precast high-strength concrete slabs with pockets and steel beam to achieve accelerated bridge construction (ABC). Twenty-six push-out specimens, with different stud height, stud diameter, stud arrangement, deck thickness, the infilling concrete strength in shear pocket (different types of concrete), steel fiber volume of the infilling concrete in shear pocket concrete and casting method, were tested in this investigation. Based on the experimental results, this study suggests that the larger stud diameter and higher strength concrete promoted the shear capacity and stiffness but with the losing of ductility. The addition of steel fiber in pocket concrete would promote the ductility effectively, but without apparent improvement of bearing capacity or even declining the initial stiffness of specimens. It can also be confirmed that the precast steel-concrete composite structure can be adopted in practice engineering, with an acceptable ductility (6.74 mm) and minor decline of stiffness (4.93%) and shear capacity (0.98%). Due to the inapplicability of current design provision, a more accurate model was proposed, which can be used for predicting the interface shear capacity well for specimens with wide ranges of the stud diameters (from13 mm to 30 mm) and the concrete strength (from 26 MPa to 200 MPa).

• Journal of the Korean Mathematical Society
• /
• v.56 no.4
• /
• pp.1001-1016
• /
• 2019

We are concerned with optimization methods for the $L^2$-Wasserstein least squares problem of Gaussian measures (alternatively the n-coupling problem). Based on its equivalent form on the convex cone of positive definite matrices of fixed size and the strict convexity of the variance function, we are able to present an implementable (accelerated) gradient method for finding the unique minimizer. Its global convergence rate analysis is provided according to the derived upper bound of Lipschitz constants of the gradient function.

• Journal of Information Processing Systems
• /
• v.18 no.4
• /
• pp.500-509
• /
• 2022

With the rapid development of educational informatization, teaching methods become diversified characteristics, but a large number of information data restrict the evaluation on teaching subject and object in terms of the effect of English education. Therefore, this study adopts the concept of incremental learning and eigenvalue interval algorithm to improve the weighted decision tree, and builds an English education effect evaluation model based on association rules. According to the results, the average accuracy of information classification of the improved decision tree algorithm is 96.18%, the classification error rate can be as low as 0.02%, and the anti-fitting performance is good. The classification error rate between the improved decision tree algorithm and the original decision tree does not exceed 1%. The proposed educational evaluation method can effectively provide early warning of academic situation analysis, and improve the teachers' professional skills in an accelerated manner and perfect the education system.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.21 no.2
• /
• pp.173-179
• /
• 2018

Estimating reliability of a non-repairable system using the degradation data, variance assumption such as homogeneity (constant) or heteroscedasticity (time-variant) could affect accuracy of reliability estimation. This paper showed reliability estimation and comparison results under normal conditions using accelerated degradation data obtained from destructive measurements, according to variance assumption of the data at each measurement time. Degradation data from three accelerated conditions with stress factors of temperature and humidity were used to estimate reliability. The $B_{10}$ lifetime was estimated as 1243.8 years by constant variance assumption, and 18.9 years by time-variant variance. And variance assumption provided different analysis results of important stresses to reliability. Thus, accurate assumption of variance at each measurement time is required when estimating reliability using degradation data of a non-repairable system.

• Journal of Engineering Education Research
• /
• v.17 no.4
• /
• pp.48-53
• /
• 2014

Recently, the tendency for young people losing interest in science has accelerated. This tendency is remarkable for not only Japan but also some countries of Asia. It is thought that this tendency was brought from the decrease of the chance to watch the actual manufacturing activities, and the decrease of the real experience which children makes something in their childhood. In order to bring up the capable engineers on such a social background, making a product practice which promotes the understanding of the application of theory for manufacturing products is important in addition to study by the text book. In this study, some practical work materials for the lower grades in the college were developed. Integration of the developed materials and the course of study becomes an effective teaching method of the of subjects on a special field. Arranging this practical work on the learning process makes a high effect of the integrated practical work on the curriculum.

• Korean Medical Education Review
• /
• v.23 no.3
• /
• pp.147-153
• /
• 2021

The coronavirus disease 2019 (COVID-19) pandemic made it necessary for medical schools to restructure their curriculum by switching from face-to-face instruction to various forms of flexible learning. Flexible learning is a student-centered approach to learning that has received interest in many educational sectors. It is a critical strategy for expanding access to higher education during the pandemic. As flexible learning includes online, blended, hybrid, and hyflex learning options, learners have the opportunity to select an instruction modality based on their needs and interests. The shift to flexible learning in medical education took place rapidly in response to the COVID-19 pandemic, and learners, instructors, and schools were not prepared for this instructional change. Through the lens of the technology acceptance model, human agency, and a social constructivist perspective, I examine students, instructors, and educational institutions' roles in successfully navigating the digital transformation era. The pandemic has also accelerated the use of advanced information and communication technologies, such as artificial intelligence and virtual reality, in learning. Through a review of the literature, this paper aimed to reflect on current flexible learning practices from the instructional design and educational technology perspective and explore emerging technologies that may be implemented in future medical education.

• The Journal of the Korea Contents Association
• /
• v.22 no.7
• /
• pp.540-547
• /
• 2022

Online education is a major trend in the future education change and the COVID-19 pandemic has further accelerated the process. Online education has become an important part of the modern education system because of its stability and continuity. However, the disadvantages of traditional online education can reduce users' experience, thus upgrading online education is the key to future education. Metaverse, as a new platform for online education, redefines the occurrence space of online education, changes the teaching mode and learning and evaluation methods of online education, and shows its development potential. This research analyzed the characteristics of Metaverse and its technological development status, and then proposed an intelligent online education environment construction scheme based focused on Metaverse of art education.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.39 no.4
• /
• pp.397-403
• /
• 2015

This paper proposes the development of a method for assessing the system reliability of an unmanned control robot system for an excavator. It then shows the results of the reliability qualification test based on the proposed method. The robot system functions to ensure the safety of the workers who control excavators in dangerous working environments, and the system reliability was calculated by integrating the reliabilities of the system components. Thus, test equipment for the three key units of the robot system were constructed and used in accelerated life testing. From the life testing results, guaranteed mean time between failures for the chosen confidence level was estimated, and the reliability qualification testing method of the robot system using small sample sizes was proposed.

• Journal of the Korean Society of Earth Science Education
• /
• v.5 no.3
• /
• pp.256-266
• /
• 2012

The purpose of this study is to use DARTs (Directed Activities Related to text) to foster inquiry problems while actively engaging accelerated gifted elementary students in the field of earth sciences. This study is continually evolving in the classroom on the proposition that accelerate the scientific thought whether inquiry problems show any change according to the extent of prior background knowledge through DARTs. Researchers appointed the accelerated gifted elementary students with 14 investigation problems and it was their duty to not only classify the inquiry problems, but to analyze using interviewing methods according to type classification framework. Many scientific terms were used concretely in the inquiry problems that were propose after DART. The students gave a direct effect to the inquiry problem to be proposed according to the level of the content that it is presented in the DARTs worksheet. As a result, the NP-IP type and the EC-IP, NC-IP inquiry problem type proposed above much as a whole in DARTs former and prior. Particularly, the EMC-IP type and etc. was variously proposed after the DARTs. And the students proposing the inquiry problem of above average proposed the inquiry problem of the EP-IP type much unlike the general average student after the DARTs. The EC-IP, NC-IP and NF-IP type were changed much after DARTs used. Particularly, the EC-IP and NC-IP type were changed much.

• Journal of Practical Engineering Education
• /
• v.14 no.2
• /
• pp.361-366
• /
• 2022

Recently, with the development of virtual and augmented reality technology, metaverse is emerging as a new paradigm that will lead the next-generation internet era, and social and economic activities are spreading around the game, entertainment, music, and content industries. Moreover, as non-face-to-face conversion accelerated after the outbreak of COVID-19, lifestyles and industrial sites are becoming untact and further rapidly becoming a metaverse. In particular, the application of metaverse to the education field is attracting attention because realistic classes using real-time voice conversations using avatars, 3D objects, and 360-degree images can increase immersion and overcome the limitations of distance education. This study examines the concept of metaverse and examines that education using metaverse can be an alternative that can increase the efficiency of education in the non-face-to-face era. In particular, it shows that it is effective in language education and suggests an actual metaverse-based Korea language education program.