• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.73-73
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• 2015

자연 하천의 홍수 유량 측정은 매우 어렵고 많은 비용과 시간, 노력을 요하는 작업이다. 보다 안전하고 경제적인 유량 측정의 대안으로 제시된 것이 하천 표면의 영상 분석을 이용하는 표면영 상유속계이다. 본 연구는 안드로이드 기반의 스마트폰을 이용한 실시간 표면영상유속계를 개발하는 것이다. 스마트폰에 내장된 카메라, GPS, 방향 센서, CPU를 활용하여, 실시간으로 현장에서 하천의 표면유속을 측정하는 것이다. 먼저, 스마트폰의 GPS를 이용하여 측정 현장의 위치를 잡고, 경사계(방향 센서)를 활용하여 카메라와 촬영면의 기하적인 관계를 설정한다. 수표면과 카메라의 높이차만을 입력하고, 측정된 카메라의 경사에서 하천 수표면의 위치관계를 추정할 수 있는 카메라 모형을 작성하였다. 이 방법을 이용함으로써 기존 표면영상유속계의 단점 중 하나인 참조점 보정이 필요없도록 하였다. 내장된 카메라로 정해진 시간(3초) 동안 동영상을 촬영하고, 촬영된 동영상은 개방 소스의 영상처리 라이브러리인 JavaCV를 이용하여 프레임별로 분할하고, 이를 시공간 영상 분석하여 하천 표면의 2차원 유속장을 추정한다. 영상의 시공간 분석에는 상호상관 시공간분석법을 이용하였다. 모든 코드는 안드로이드 운영체제에서 실행되도록 Java로 작성하였다. 시판되는 안드로이드 스마트폰에 적용하여 현장 시험한 결과 3초간의 영상 처리에 5초 정도를 소요하여, 거의 실시간으로 유속을 측정할 수 있었다. 또한 유속 측정 오차는 일반적인 영상 처리의 오차인 5% 내외였다.

• Journal of the Society of Disaster Information
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• v.20 no.1
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• pp.13-19
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• 2024

Purpose: This study provides prevention methods by type of construction disaster using text mining techniques. Method: Based on the database that analyzed the cases of critical disasters in the domestic construction sector, preventive measures and causes are analyzed by text mining techniques, and the contents of the analysis are visually shown. Result: This visual data represents the measures for preventing critical disasters of each process according to the importance. Conclusion: It is believed that the results will be helpful in identifying factors to be considered in preparing preventive measures for serious accidents in construction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.493-500
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• 2017

Co-operative education and internships are generally treated as an alternative way to increase the employment rate by resolving the mismatch between college education and the industrial needs of the job specification. Based on a questionnaire survey on Korean universities, this study examined the current status of programs and the operating mechanism for co-operative education and internship to provide policy suggestions for promoting the depth and width of co-operative education in Korean universities. The results of the survey shows that the majority of students carry out internships on a short-term basis and the universities usually lack the capabilities for effectively running the programs of co-operative education and internships. In particular, as a part of the academic curriculum, co-operative education should be focused on the balance and effective linkage between the occupations given to students and the majors in university.

• Journal of the Korean Geotechnical Society
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• v.31 no.2
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• pp.47-63
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• 2015

A fundamental study of drilled shafts subjected to lateral cyclic loading in weathered soil was carried out based on field tests and numerical analysis. The emphasis was given on quantifying the cyclic p-y curve function from lateral cyclic loading tests and three-dimensional finite element analysis. Lateral cyclic loading tests and three-dimensional finite element analysis were carried out to investigate the behavior of drilled shafts according to the direction of cyclic loading. Based on the field tests and numerical analysis, a modified lateral load transfer relationship and design chart with degradation factors were proposed by considering the characteristics of cyclic loading. It was found that the prediction by the proposed p-y curve function is in good agreement with the general trends observed by in-situ measurements, and it represents a practical improvement in the prediction of lateral displacement and bending moment distribution of drilled shafts subjected to cyclic loading.

• Journal of the Korea Institute of Building Construction
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• v.9 no.4
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• pp.103-109
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• 2009

The construction industry has the highest death rate related to safety accidents of any industry. Furthermore, in contrast to other industries, where the death rate related to safety accidents has been steadily declining, both the death toll and the number of accidents in the construction industry have been on the rise. Construction accidents occur when various risks increase in an intertwined way to reach a tipping point; a moment when such factors cannot be tolerated any longer Conventional safety management methods have restrictions in terms of their ability to fully prevent all types of safety accidents. This research considers ways in which USN technology can be applied to safety management on a construction site, and derives a method of applying USN technology for safety management monitoring. The tasks related to safety management on construction sites, as well as the occurrence of accidents, are first analyzed. By analyzing the characteristics of construction accidents, the factors that must be a priority and the factors that can be a lower priority are derived. Finally, the configuration of a monitoring system for safety management on a construction site to which USN technology is applied is presented. It is expected that safety accidents can be prevented from occurring on construction sites by applying this cutting-edge USN technology.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.3
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• pp.229-243
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• 2013

An in situ solute migration system was designed and installed in KAERI Underground Research Tunnel (KURT) constructed in the site of Korea Atomic Energy Research Institute (KAERI) in order to investigate the migration and retardation of non-sorbing and sorbing tracers through a rock fracture. The system is composed of three main parts including injection, extraction, and data treatment. For the selection of a water-conducting fracture, boreholes were drilled. The fractures in the drilled boreholes were investigated using borehole image analysis using borehole image processing system (BIPS). The results of BIPS analysis showed that borehole YH 3-1 and YH 3-2 were connected each other. Moreover, hydraulic tests were carried out to determine the test section with connectivity for the in situ experiments. The in situ solute migration experiments were accomplished to understand the migration of solutes through fractures in KURT using non-sorbing tracers which were fluorescein sodium, eosin-B, bromide and sorbing tracers which were rubidium, nickel, zirconium, and samarium.

• Journal of the Korean Society for Library and Information Science
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• v.57 no.4
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• pp.75-95
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• 2023

This study investigated the overall perceptions of pre-service school librarian teacher on the current education practicum through semi-structured in-depth interviews and suggested improvements to the educational practicum system. For this purpose, interview data were collected from 28 pre-service school librarian teacher (6 teachers' colleges, 14 taking teaching qualification courses, and 8 graduate school of education) who participated in educational practicum in school libraries, and a research method that combines qualitative analysis techniques with text network analysis was applied. The results of the study showed that pre-service school librarian teacher believe that educational practicum can prepare them for various field experiences and cultivate their ability to cope with situations they will encounter in the future. Through qualitative inquiry, we were able to identify their perceptions of school field practicum as a whole, their perceptions of the school field practicum, and their perceptions of educational service activities. Based on this, to improve the current problems of educational practice, we suggested expanding the period of school internship program, distributing the time, establishing a full-time practice system, having continuous discussions with field teachers, and developing a systematic school field practicum.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1995.10a
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• pp.541-544
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• 1995

• Agrochemical news magazine
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• v.20 no.2 s.149
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• pp.10-13
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• 1999

• Proceedings of the Korean Geotechical Society Conference
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• 1997.10a
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• pp.399-408
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• 1997