• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.74-79
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• 2020

Safety inspection of cable-supported bridge has increasingly attention as many cable-supported bridges are currently constructed/operated. Whilst cables as a main component in cable-supported bridge should be inspected regularly, traditional method (visual inspection) has limitation to check the condition of cables properly due to restricted factors. It is evidently necessary to develop cable-inspection robot to overcome this concern. In this respect, the main aim in this study is to manufacture the improved robot compared with the existing robot. The improved functions of the robot in this study were that the robot can be operated in large cable diameter (greater than 200 mm) and climbing ability of the robot increases. In addition, electro-magnetic sensor as a non-destructive method in the robot was added to detect damaged cables and performance of the sensor was evaluated in indoor and field experiments. Consequently, the robot was able to move on the cable with ~0.2m/s and to detect damaged cables using the sensor. It was also confirmed that performance of the robot in field test is similar to that in indoor test.

• Journal of the Korean Chemical Society
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• v.63 no.5
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• pp.360-375
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• 2019

The purpose of this study was to investigate beginning science teachers' perceptions of inquiry-based science instruction using open-ended questionnaire and semi-structured interview. Participants of this study voluntarily set up a goal of inquiry-based science instruction, planned inquiry-based science lessons, and shared and reflected their teaching experiences in their professional learning community for more than a year. Participant teachers recognized students' construction of core scientific concepts through performing scientific inquiry as a goal of science inquiry instruction. Participant teachers indicated that goals of science education such as 'learning scientific core concepts', 'improving students' interest of science', 'improving scientific thinking', and 'understanding the nature of science' can be achieved through students' active engagement in scientific inquiry. Participant teachers recognized not only the importance of teachers' role, but also what roles science teachers should play in order to enable students to perform scientific inquiry. Participant teachers emphasized teachers' roles such as 'identifying core concepts', 'reorganizing science curriculum', 'considering student ability', 'asking questions and providing feedbacks to students', 'explaining scientific concepts', and 'leading students' argumentation.'

• Polymer(Korea)
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• v.33 no.2
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• pp.104-110
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• 2009

Demineralized boneparticle (DBP) has been widely used as and a powerful promoter of new bone growth. In this study, DBP sponges were chemically crosslinked and characterized for the potential application of tissue engineered scaffolds. The DBP sponges prepared by crosslinking with EDC. 0.1, 0.2 or 0.3% pepsin was applied to DBP dissolved in 3% (v/v) acetic acid aqueous solution for 48 hrs. The prepared sponges were crosslinked by 1, 5, 10, 50 or 100 mM of EDC solution concentration and then were lyophilized. The DBP sponges were characterized by SEM, FT-IR and DSC and analyzed in terms of their porosity and water absorption ability. The cellular viability and proliferation were assayed by MTT assay. Our investigation revealed that 0.2$\sim$0.3% of pepsin and 50$\sim$100 mM of EDC produced DBP sponges with good physical characteristics. In conclusion, DBP sponge prepared under these conditions is potentially useful for the applications of tissue construction.

• Journal of The Korean Association of Information Education
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• v.25 no.5
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• pp.691-704
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• 2021

The development of AI technology has brought about a big change in our lives. The importance of AI and data education is also growing as AI's influence from life to society to the economy grows. In response, the OECD Education Research Report and various domestic information and curriculum studies deal with data literacy and present it as an essential competency. However, the definition of data literacy and the content and scope of the components vary among researchers. Thus, we analyze the semantic similarity of words through Word2Vec deep learning natural language processing methods along with the definitions of key data literacy studies and analysis of word frequency utilized in components, to present objective and comprehensive definition and components. It was revised and supplemented by expert review, and we defined data literacy as the 'basic ability of knowledge construction and communication to collect, analyze, and use data and process it as information for problem solving'. Furthermore we propose the components of each category of knowledge, skills, values and attitudes. We hope that the definition and components of data literacy derived from this study will serve as a good foundation for the systematization and education research of AI education related to students' future competency.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.200-207
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• 2019

Cement is one of the most commonly used materials in the construction and civil engineering industry. However, emissions of carbon dioxide generated during the production of cement have been linked to climate change and environment pollutants. In order to replace cement, many studies have been actively performed research to utilizing Blast Furnace Slag(BFS), which is a byproduct of the steel industry. This study aims to investigate the physiochemical properties of the BFS powder based grout to determine whether it can be used as an environment-friendly grout material. As a fine powder, BSF can be used instead of cement grout due to its potential hydraulic property. BSF has also been known for its ability to strengthen materials long-term and to densify the internal structure of concrete. In order to investigate the physicochemical properties of the BFS powder based grout as a grout material, in this study assessment tests were performed through a gel-time measurement, uniaxial compressive strength, and chemical resistance tests, and heavy-metal leaching test. Characteristics and advantages of the slag were studied by comparing slag and cement in various methods.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.272-278
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• 2018

Traffic volume has been greatly increasing due to urban development and the improvement of living standards, and many complaints are being raised due to the increasing road noise. As a countermeasure against these problems, highly soundproof walls are installed on the sides of roads. However, the ability to bear wind loads is a major design requirement for soundproof walls, which contributes to the exponential increases in construction costs and restricts the height of the walls. The aim of this study is to improve the performance of soundproof walls and to dramatically reduce wind loads while maintaining excellent price competitiveness. Based on Helmholz's resonator theory, a new concept is proposed for a ventilation-type soundproofing plate that can pass through a fluid like air and reduce noise. A full-scale metal soundproofing plate was produced to satisfy the quality standards of highways by conducting a sound-pressure transmission-loss test, wind tunnel test, and material quality test. To verify the reliability, the wall was manufactured and installed, and the sound insulation effect was examined by measuring the noise over time. In the future, ventilated soundproof walls on roads could create a pleasant living environment due to the high noise-insulation effect.

• Journal of Digital Convergence
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• v.19 no.4
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• pp.355-363
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• 2021

The purpose of this research is to explore the selection attributes that the director of a taekwondo gym places importance on when purchasing a work of taekwon gymnastics for the competition. We conducted in-depth interviews with 6 participants using qualitative case study techniques, and analyzed data using Creswell's (2015) spiral analysis method. The data analysis results show music, trainees, characteristics of the work, criteria for evaluating the competition, producer competence, and price factors. As a result of the research, music should be produced around diverse and differentiated genres and music preferred by the trainees, and the appropriate theme should be selected considering the expressiveness and level of the trainees. The work should be considered creative works that harmonize the movement ratio of Taekwondo movements and dance, and the length of the work should be adjusted according to the purpose of the buyer, and the construction of the work should be based on the regulations of the competition. The manufacturer should ensure smooth communication with the buyer, including coaching ability and experience at the convention site. Prices will be affordable and affordable, and prices will need to be calculated based on special prices or mentoring periods for a small number of buyers.

• (The)Study of the Eastern Classic
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• no.37
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• pp.345-375
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• 2009

In relation to body conception, the introduction of western medicine to Joseon Korea started off some points in disputes: the one was whether the western anatomy was positive or not, the other was whether the cognition was ruled by heart or brain. In the long run of these disputes, that who had clarified the change of body conception was Choi Han Kee. His new conception of body was characterized as follow: on the one hand, it emphasized the mechanical conception of body; on the other hand, it emphasized the cognitive ability of body. But that his conception of body had obscure points: that is, its mechanical conception was intervened by chi(神氣), and his doctrine of cognition searched for the origin of cognition in balance of chi of the body. He had set up this conception of body by the combination of western medicine and chi, but the combination did not seem to be perfect. This point had appeared again in his conception of physics that he thought the basis of medicine. He had pursed the combination of chemical element and chi, but it could not be accomplished successfully unless he had abandoned the organicist conception of chi. In conclusion, his new conception of body was not free from the suspicion of a incomplete tentative construction.

• (The)Study of the Eastern Classic
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• no.57
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• pp.359-382
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• 2014

This paper is an essay on Chaekmun(Answer papers of official examination in Pre-modern period). Especially I tried to point out the possibility of practical use in the field of politics. For this purpose, I analyzed an examination paper written by Lee Ga-hwan, and the title is "a debate about construction of the Miang palace". Exquisite writing skill is also important in Chaekmun, but it is not everything. The subject of Chaekmun concerns various fields such like politics, economy, society, culture, and history. So that writers should have sufficient knowledge and opinion. The King, as an examiner, wants to test retainers' ability both in writing and politics. In this paper, I focused on using in field of politics between the King and the retainers. And as an good example, I analyzed a paper which dealt the event of building huge palace named Miang palace. That is because the King reflects his concerns by setting exam questions. And his concerns also could not be free of contemporary political conditions. Therefore we should be careful of reading those articles. Regarding this, Lee Ga-hwan's article had a distinctive characteristic. Unlike any other articles dealing with same event, he tried to access through creative point of view. And his thought were much close to the King's heart.

• Journal of the Korean Geosynthetics Society
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• v.20 no.1
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• pp.35-44
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• 2021

This research studies the stabilization method for improved soil sloped through the on-site application of Paper Flyash ground stabilizers. The target strength required for improved soil is 500 kPa, and the compressive strength for the slope surface needs to be less than 1,000 kPa after the improvement in order to plant vegetation. To meet this condition, we mixed soil from the site and the ground stabilization material, which is the main material for surface improvement material, performed mixing design and conducted various tests including strength test, permeability test and plantation test. After analyzing the results of the compression test on improved soil slope, we proposed soil constants for the improved soil. In order to evaluate the applicability of the improved soil on the slope, the site construction was carried out on the collapsed slope and the reinforcement evaluation of the surface of the improvement soil was conducted. The stability was not secured before the reinforcement, but the test shows after the reinforcement with improved soil, the safety rate is secured up to 48 hours during the raining period. In addition, the compressive strength of the improved soil at the site was secured at more than 200 kPa adhesion as planned, and the soil hardness test result was also found to be within the specified value of 18-23 mm, which increased the resistance to rainfall and ability to grow plant on the surface for improved soil.