• 대한안전경영과학회지
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• 제22권3호
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• pp.1-8
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• 2020

The desulfurizers facility is cylindrical shape. To operate properly it needs nozzles cleaned, get rid of lime adhesion and sludge, repair the wear and corrosion of facility regularly. For this purpose, workers shall access the ceiling or vertical wall at high place. Ordinary scaffoldings such as steel pipe scaffolding or system scaffolding have been using so that workers can access them. With these ordinary scaffoldings, openings around cylindrical wall are inevitable which make workers can expose always to the risk of falling. The purpose of this study is to develop customized scaffolding to minimize the openings to prevent workers form falling during maintenance it. It consists of a hexagonal central tower and six trapezoidal outer towers. And the bracing among the towers have connected each other for self-standing and for maintaining the structure of towers. Span decks, the circumference footstools, steps, etc. are laid on each floor. The safety is reviewed by structural analysis and performance test. With this study, openings each floor of this scaffold are removed. The gap between the cylindrical wall and the edge of the work stage is approximately 100 mm. Therefore, we expect that workers can work safely and efficiently.

• 한국학교수학회논문집
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• 제10권2호
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• pp.263-288
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• 2007

본 연구는 수학 7-가, 수학 8-가 교과서의 함수단원 분석을 통해 지필환경의 제한점을 알아본 후 탐구용 소프트웨어인 엑셀이 학생들의 일차함수의 과정-대상관점 형성 과정에 어떠한 영향을 미치는지 알아보는 것이다. 엑셀을 활용한 교수 실험은 학습능력 수준이 다른 다섯 명의 학생을 선정하여 중학교에서 다루고 있는 함수관련 내용을 중심으로 실시하였다. 교수실험은 5차시로 이루어졌으며, 각 학생의 활동 과정을 녹화, 녹음한 내용과 학생과의 면담, 관찰, 활동지 등을 분석하였다. 교수실험 결과, 엑셀을 활용해 식과 표와 그래프를 다양하게 조작한 역동적 탐구활동은 일차함수의 과정관점과 대상관점을 형성하는 데 중요한 비계설정(scaffolding) 역할을 했다.

• 대한조선학회논문집
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• 제58권5호
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• pp.303-313
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• 2021

Recently, quality control of the Liquefied Natural Gas Carrier (LNGC) cargo hold and block-erection interference areas using 3D scanners have been performed, focusing on large shipyards and the international association of classification societies. In this study, as a part of the research on LNGC cargo hold quality management advancement, a study on deep-learning-based scaffolding system 3D point cloud object detection and post-processing were conducted using a LNGC cargo hold 3D point cloud. The scaffolding system point cloud object detection is based on the PointNet deep learning architecture that detects objects using point clouds, achieving 70% prediction accuracy. In addition, the possibility of improving the accuracy of object detection through parameter adjustment is confirmed, and the standard of Intersection over Union (IoU), an index for determining whether the object is the same, is achieved. To avoid the manual post-processing work, the object detection architecture allows automatic task performance and can achieve stable prediction accuracy through supplementation and improvement of learning data. In the future, an improved study will be conducted on not only the flat surface of the LNGC cargo hold but also complex systems such as curved surfaces, and the results are expected to be applicable in process progress automation rate monitoring and ship quality control.

• 한국안전학회지
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• 제32권3호
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• pp.34-40
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• 2017

The catastrophic collapse of the in-boiler scaffolding system in the two thermal power plants occurred in March and April 2012. After site investigation and document review, it was found that the specialized scaffolding system was imported for overhaul & maintenance and that the system did not get the safety certification at the import. In this regard, this study developed & proposed an access platform and a support for the vertical tube section of the super heat as well as a variable-length platform for the horizontal tube section, satisfying the domestic certification standards. The access platform was developed to be easy to handle by the worker with a weight of about 0.069 kN, which could reduce the risk of falling accidents and workers' musculoskeletal diseases. For the variable-length platform, it is possible to cope with various changes in length between the horizontal tubes associated with the increase of rigidity in the overlapping and the elimination of the protrusion.

• 한국안전학회지
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• 제21권3호
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• pp.67-72
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• 2006

This study is to investigate the related materials such as domestic law regulation, research paper, research report, and the other material, and to suggest suitable counter measures, to find out hazard degree for its works of workers and work place through direct survey, in order to determine risk score of each hazardous work which is designated by the Government, without consideration of labour's consciousness against risk level at a site. Therefore, a new questionnaire survey related to the decision of risk level are made and distributed to find out what risk level each worker recognizes. Also, the authors tried to approach reasonable conclusions after discussing reasonability of qualification standard and improving ideas of worker at hazardous work places with worker, faculty member, H&S manager, labour union. And the results show hazard degrees by each work kind of the above: 3.75 for working with machinery, 3.7 for steel structure, 3.5 for operation of tower crane, 3.51 for retaining wall, 3.85 for form work, 3.46 for scaffolding are obtained. This quantified risk can be applied to establishing a reasonable system to keep safe against hazardous works.

• 한국안전학회지
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• 제33권1호
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• pp.73-80
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• 2018

According to the statistics publication of KOSHA, more than half of serious accidents at the construction sites were related to the temporary works and/or the temporary structures such as scaffoldings, shores, earth retaining walls, etc. The structural failures are occurred because of the overload acting on the structures or lack of performance of the one or more members of the structures. For the prevention of the collapse accidents relating to the temporary structures at the construction sites, we have to control construction processes not to occur the overload and also to control the performance and quality of each member of the temporary structures. MOLIT has amended the "Construction Technology Promotion Act" on Jan. 7th, 2015 to ensure the structural safety of the temporary structures. According to the Act, the designers of the construction design projects should check the structural integrity of the structures including the temporary structures and the construction companies have to let 'the Relative Professionals' confirm the structural integrity of temporary structures, the shores(${\geq}5m$ high) and the scaffolds(${\geq}31m$ high), before construction. Also, MOLIT has amended the "Regulation for Construction Technology Promotion Act" on Jul. 4th, 2016 for quality management and testing of temporary equipments. According th this regulation, the construction companies and supervisors should manage and test the temporary equipments before using them. In this paper, the standard drawings of the shores(< 5 m high) and the scaffolds(< 31 m high) and the amended "Business Guideline for Quality Management of Construction Work" are presented. As the result of this study, MOLIT noticed the amended "Business Guideline for Quality Management of Construction Work" on Jul. 1st, 2017.

• 한국안전학회지
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• 제16권2호
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• pp.80-84
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• 2001

Work stress and health are very important factors related to workers' condition and work safety, Author has conducted a couple of tests to check up three people's pulses before they work during their work for three types of safety guard in construction site. Work type, age, weight, sex experience year, ambient temperature n recorded as variables in this study. These are checked and asked by the author directly, before their pulse check Also, workers' Pulses were measured at height H-0 and H-9.0m to understand psychological the degree of psychological nervousness degree. POLAR protrainer NVTM HRM system(wrist recorder and sensor) was used for the site test. There are three(3) different types of construction safety guard which have been used for, this study. They are usually or frequently used and found in the site. Four different ranges of age groups(20's, 30's 40's, 50's) carpenters are assisted to the test sites with wearing pulse recorder and sensor respectively. All three types of safety guards have the same height 90㎝ even though they are different types. On top of five(5) stories tublar framed scaffolding is fabricated, similar to the one in site, where those safety guards are installed. The older(=more experienced) the workers are the more stable they are. it is shown. Also, It is verified the visually uncomfortable rail type can cause workers to psychologically be unstable.

• 한국지구과학회지
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• 제25권3호
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• pp.194-204
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• 2004

The purpose of this literature review is to investigate what kinds of research have been done about scientific inquiry in terms of scientific argumentation in the classroom context from the upper elementary to the high school levels. First, science educators argued that there had not been differentiation between authentic scientific inquiry by scientists and school scientific inquiry by students in the classroom. This uncertainty of goals or definition of scientific inquiry has led to the problem or limitation of implementing scientific inquiry in the classroom. It was also pointed out that students' learning science as inquiry has been done without opportunities of argumentation to understand how scientific knowledge is constructed. Second, what is scientific argumentation, then? Researchers stated that scientific inquiry in the classroom cannot be guaranteed only through hands-on experimentation. Students can understand how scientific knowledge is constructed through their reasoning skills using opportunities of argumentation based on their procedural skills using opportunities of experimentation. Third, many researchers emphasized the social practices of small or whole group work for enhancing students' scientific reasoning skills through argumentations. Different role of leadership in groups and existence of teachers' roles are found to have potential in enhancing students' scientific reasoning skills to understand science as inquiry. Fourth, what is scientific reasoning? Scientific reasoning is defined as an ability to differentiate evidence or data from theory and coordinate them to construct their scientific knowledge based on their collection of data (Kuhn, 1989, 1992; Dunbar & Klahr, 1988, 1989; Reif & Larkin, 1991). Those researchers found that students skills in scientific reasoning are different from scientists. Fifth, for the purpose of enhancing students' scientific reasoning skills to understand how scientific knowledge is constructed, other researchers suggested that teachers' roles in scaffolding could help students develop those skills. Based on this literature review, it is important to find what kinds of generalizable teaching strategies teachers use for students scientific reasoning skills through scientific argumentation and investigate teachers' knowledge of scientific argumentation in the context of scientific inquiry. The relationship between teachers' knowledge and their teaching strategies and between teachers teaching strategies and students scientific reasoning skills can be found out if there is any.

• 한국지구과학회지
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• 제35권2호
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• pp.147-158
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• 2014

본 연구의 목적은 탐구를 도모하는 과학글쓰기를 이용한 학생주도적 모둠 탐구활동을 실시한 과학수업에서 나타난 변화를 탐색하는 것이다. 본 연구에서는 학생의 활동 보고서, 학습 환경에 대한 인식, 담화유형을 변화의 핵심으로 보았다. 학생들의 탐구활동에서 비계의 역할을 할 수 있도록 과학 글쓰기 활동지를 개발하여 초등학교 4학년 1학급 29명의 학생을 대상으로 학생주도적 모둠 탐구활동에 적용하였다. 이를 위해 모둠 탐구활동은 2007 개정교육과정 4학년 1학기 4개 단원에서 총 16차시 수업을 실시하였고, 이를 모두 녹화하였다. 우선 학생 보고서를 분석하기 위해 Millar (2010)가 제시한 분석틀을 이용하여 과학탐구 정합성 평가의 틀로 활용하였다. 두 번째로 학생의 과학 수업 및 과학에 대한 인식의 변화를 알아보기 위하여 비교반 1개 반을 선정하여 과학수업 및 과학에 대한 인식을 사전 사후 비교하였다. 마지막으로 16차시 수업 중, 초기 수업과 말기 수업에서의 교사와 학생 간의 담화 형태가 어떻게 나타나는지 알아보았다. 이러한 과정을 통하여 얻어진 결과 통해 학생의 질문과 주장 사이의 정합성은 초기보다 말기에 증가했고, 학생의 자신의 학습 환경에 대한 인식이 좀 더 학생 중심 쪽으로 이동한 것을 알 수 있었다. 또한 담화의 유형이 더욱 교사중심보다는 학생중심에 가까워졌음을 발견하였다.

• 국제초고층학회논문집
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• 제4권3호
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• pp.161-169
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• 2015

Experience on the construction of several 100-plus-story skyscrapers including Guangzhou West Tower, Guangzhou East Tower, and Shenzhen's KK100 is described considering the increasingly strong development trend of 100-plus-story skyscrapers in China. Difficulties in the construction of 100-plus-story skyscrapers are investigated. Four innovative construction technologies receive detailed descriptions: intelligently and entirely-jacked work platforms, formwork and suspension scaffolding systems ("jacking and formwork systems"), multi-function low-carbon concrete, 5D-BIM ("five-dimensional building information modeling"), and safe and rapid vertical transport, as they have found successful applications in actual projects. Popularized systematically as technical achievements, these technologies will significantly influence the construction of similar projects in the future, and produce more social and economic benefits.