• Steel and Composite Structures
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• v.52 no.6
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• pp.695-711
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• 2024

Suspension bridges are critical to urban transportation, but those in earthquake-prone areas face unique challenges. In the event of a moderate or strong earthquake, conventional linear theory-based approaches for detecting bridge damage become inadequate. This study presents an efficient method for identifying damage in suspension bridges using time history nonlinear inelastic analysis. A practical advanced analysis program is employed to model cable-supported bridges with low computational cost, generating a dataset for four hybrid models: PSO-DT, PSO-RF, PSO-XGB, and PSO-CGB. These models combine decision tree (DT), random forest (RF), extreme gradient boosting (XGB), and categorical gradient boosting (CGB) with particle swarm optimization (PSO) to capture nonlinear correlations between displacement response and damage. Principal component analysis reduces dataset dimensions, and PSO selects the optimal model. A numerical case study of a suspension bridge under simulated earthquake conditions identifies PSO-XGB as the best model for predicting stiffness reduction. The results demonstrate the method's robustness for nonlinear damage detection in suspension bridges under earthquake excitation.

• Proceedings of the Korea Database Society Conference
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• 1997.10a
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• pp.24-48
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• 1997

. Supported byㆍDARPA′s image Understanding (IU) program under "Video Retrieval Based on Language and image Analysis" project.DARPA′s Computer Assisted Education and Training Initiative program (CAETI)ㆍObjective: Develop practical systems for automatic understanding and indexing of video sequences using both audio and video tracks(omitted)

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.1
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• pp.106-113
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• 2004

Most of mechanical structures are composed of many substructures connected to one another by various types of mechanical joints. In automotive engineering, it is important to study these connected structures under various dynamic forces for the evaluations of fatigue life and stress concentration exactly. In this study, the dynamic response of vehicle structure to external forces is classified an inverse problem involving strains from the experiment and the analysis. The practical dynamic forces are determined by the combination of the analytical and experimental method with analyzed strain by quasi-static finite element analysis under unit force and with measured strain by a strain gage under driving load, respectively. In a stressed body, inter-molecular chemical bonds are failed beyond the certain magnitude. The failure of molecular structure in material is considered as a time process of which rate is determined by mechanical stress. That is, the failure of inter-molecular chemical bonds is the fatigue lift of material. This kinetic concept is expressed as lethargy coefficient. And S-N curve is obtained with the lethargy coefficient from quasi-static tensile test. Equivalent practical dynamic force is obtained from the identification of practical dynamic force for one loading point. Using the practical dynamic force and S-N curve, fatigue life of a window pillar is analyzed with FEM under the identified force by the procedure of above mentioned.

• Archives of design research
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• v.16 no.3
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• pp.281-290
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• 2003

An educational practice is a communicational course between educator and student with scheme and execution of studying. The communicational contents of the practical course require teaching transmission and recipient process for educator and student as a major knowledges end techniques in order to achieve student's aim. The communication of practical course consists of educators, students, and practical contents, and they also form both meaning objects and mutual relationships for constitution of the practical courses. In order to develop the effective plan for practical process, we have to understand the phenomena of meaning operations which consists in connections of the practical exercise and the meaning object. This study is to approach a phenomenal analysis as respects the meaning operations how forms of tie meaning object exert in the practical course. On the basis of this analysis, we grasp properties of the practical course into the meaning object, and in these connections, suggest the category of cognizance to put execution in the practical course by interpreting factors of the meaning operations.

• Journal of Information Technology Applications and Management
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• v.27 no.2
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• pp.23-36
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• 2020

The promulgation of the overall framework of Chinese students' development of core literacy has made the implementation of core literacy into specific teaching activities an urgent problem to be solved in the field of education. Based on the analysis of the problems existing in the undergraduate education under the mode of emphasizing theory and neglecting practice, this paper constructs the practical teaching system of Database Principle Course Based on the core quality, expounds the implementation strategy of practical teaching, and probes into how to train the students in the practical teaching of database principle Cultivate scientific spirit, learning ability, practical innovation, responsibility and other core literacy. After 5 rounds of practice, students have achieved better development in independent development and collaborative work, and their awareness of practical innovation has been significantly improved.

• Korean Journal of Child Studies
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• v.27 no.3
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• pp.241-254
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• 2006

In this study of the effects of practical intelligence and stress on children's stress coping behaviors, 446 children responded to the Practical Intelligence Inventory(Young Hwa Lim, 2001), the Daily Hassles Scale(Ha Young Min & An Jin Yoo, 1998), and the Daily Hassles Coping Scale(Ha Young Min & An Jin Yoo, 1998). Data were analysed by Pearson's correlation, multiple regression analysis, and two-way ANOVA. Results were that stress coping behaviors were correlated with practical intelligence and stress. Practical intelligence and stress had effects on stress coping behaviors, but stress had stronger effects than practical intelligence.

• Human Ecology Research
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• v.57 no.3
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• pp.383-393
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• 2019

This study examined the association among practical teaching competence (PTC) and teaching efficacy (TE), and explored the mediation effects of theoretical teaching competence (TTC) between the PTC and TE of Practical Arts (Technology and Home Economics Education) teachers. Data were collected from the 301 survey responses completed by elementary, middle, and high school teachers. All teachers showed high levels of PTC, TTC, and TE. Elementary school teachers perceived higher PTC than middle and high school teachers. PTC, TTC, TE showed significant effect in regards to teacher's age and teaching career. Using multiple regression analysis, this study found that TTC fully mediated PTC and TE of elementary school teachers. For middle and high school teachers, there was a partial mediation effect of TTC in the relationship between PTC and TE. This study suggests that teacher education programs should develop a program that can enhance teaching efficacy by cultivating TTC and support teachers who want to strengthen competence, and more practical opportunities to practice teaching.

• Human Ecology Research
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• v.59 no.4
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• pp.433-448
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• 2021

The purpose of this study was to analyze two subject competencies (practical problem-solving capability and independent life capability) reflected in the activity tasks included in the 'home life and safety' area of 12 middle school technology-home economics textbooks in accordance with the 2015 revised curriculum. The analysis criteria were sub-elements of two subject competencies. Seven sub-elements were derived from each competency. Frequency analysis was performed to determine how often the sub-elements were reflected in the activity tasks. The results were as follows. First, with regard to the sub-elements of 'practical problem-solving capability', 'value judgment' was reflected most frequently in the activity tasks followed by 'exemplification of solution', 'logical thinking', 'critical thinking', 'decision-making', 'practical reasoning', and 'evaluation of solutions'. Secondly, the sub-elements of 'independent life capability' were unevenly distributed in the activity tasks. The 'capability to perform conscious living' was reflected most frequently followed by 'development and self-identity', 'time, money, and leisure management', and 'reasonable consumption and resource utilization'. For teachers wanting to teach activity-oriented classes and student participatory classes, the results pinpoint the materials necessary to develop learners' subject competencies by using textbooks from different publishing companies.

• Archives of design research
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• v.19 no.5 s.67
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• pp.75-84
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• 2006

The aims of this study are to examine the conceptual contents of space diagram, and to find its elements and practical applications by analyzing the UN Studio. The Findings of this study are as follows: firstly, the conceptual contents represented in space diagram are classified into four elements - motif, flow, relationship, and distribution. Secondly, space diagram is used in program development, schematic design, and preliminary design of design process phases. Thirdly, the elements based on the case diagrams include five elements: context analysis, object analysis, time-behavior analysis, modeling analysis, and space analysis. Fourthly, in practical use, diagrams with motif concept is usually used in modeling analysis, and diagram with flow concept is commonly used in the analysis of time-behavior and object. Diagrams with relationship concept is mostly used in space analysis, secondly in analysis of context and modeling. Further, diagrams with distribution concept is usually used in space analysis. If one uses these findings for design projects in practical business or education, it would be helpful in design conception and development as well as of design information structuralization.

• Proceedings of the KIEE Conference
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• 2004.11b
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• pp.155-157
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• 2004

Voltage control and stability problems are very important in the electric utility industry. But there is no voltage stability analysis program which has reliability as commercial program in domestic. We are developing a practical voltage stability analysis program. In this paper, we will study the existing commercial program and then discuss design of practical analysis tool.