• Journal of Korean Society of Steel Construction
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• v.29 no.5
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• pp.389-400
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• 2017

Based on U-shaped composite beam, the new form of AU-composite beam were developed to create economical and efficient components reducing the cost and shortening the length of construction work. Because the U-shaped sections are open and needs to be fixed by topping concrete securely. Therefore, it is required to maintain the U-shaped sections in a structure and to work in the safe condition through construction. It also requires accessories that resist the horizontal shear force for synthesis between the top and bottom of the U-shaped section. To reinforce these shortcomings, a shear connector has been developed with various purposes of steel plate anchors. In this study, the steel plate anchors were directly tested and the shear force was evaluated by the horizontal shear force. The experiment was divided into two types, depending on the applicable deck plates. As a result of the experiment, the continuous type specimens showed greater resistance in both strength and displacement than the ones of stud anchor specimen. In discontinuous type case, due to shear simulations and simple element analysis, the less increase the ratio of width to height and the more shear strength decreased. Thus, the shear strength equation of the stud anchor was modified to suggest the new shear strength based on the testing results.

• Journal of the Korean association of regional geographers
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• v.13 no.2
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• pp.201-219
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• 2007

To understand the structure and dynamics of different forms of learning, whether incidental or conscious, we have to study them as parts or aspects of concrete historical activities with specifiable contexts. This realization is more embodied in apprenticeship learning situations of the student teachers. In this perspective, this paper aims to understand the student teachers' experience on geography teaching as a participant observer in the secondary schools. The 9 student teachers during the teaching internship have written their 38 journals, which was quality analysed to find out key concepts for the purpose of this research. Major conclusions are suggested below as follows. First, the most student teachers were experienced in geography teaching in the secondary schools through the 2-weeks practice teaching. Second, in the positive perspective, student teachers observed on that teachers would teaching well interact with student and experienced teachers would settle down to student's studies. Third, in the negative perspective, student teachers observed on that teachers lecture with only text, and cooperative learning by student presentation in the geography class. Finally, In third person perspective, there is no students' or teachers' productive questions in the whole-class conversation. In addition to that the most mentor teachers lecture do all of the talking in class. In effect these student teachers' experiences, especially 'reality of the geography teaching' and 'practical knowledge of the novice mentor teachers or experienced mentor teachers', either reinforce or modify understanding about the geography teaching practices.

• Journal of the Society of Disaster Information
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• v.19 no.1
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• pp.138-145
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• 2023

Purpose: In accordance with the increase in the number of buildings repaired and reinforced following deterioration from when a fire occurs in a previously reinforced building, the impact on the structure after the fire is analyzed to establish standards for repair and reinforcement measures. Method: After curing for 28 days, the process was to measure the compressive strength and induce destruction through a compressor, repair and reinforce it with epoxy, and conduct a re-compressive strength test on some specimens after curing for 3 days to understand the degree of strength restoration. The rest of the repaired and reinforced specimens as well as the unrepaired and unreinforced specimens were then put into an oven and heated according to the temporal and temperate conditions listed below, and then the compressive strength was tested to estimate the impact of fire. Result: After reinforcing the yielded specimen with epoxy, the process was to then put it in an oven and heat it at different temperatures over time. It was found that there was a decrease in the strength of the reinforcement more than that of the actual specimen. Conclusion: Based on this, it was found that a building repaired and reinforced with epoxy resin is actually more dangerous than a general unrepaired building when it is damaged by fire, and thus, that it must be prepared for fire vulnerabilities.