• International conference on construction engineering and project management
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• 2024.07a
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• pp.1319-1319
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• 2024

• Computers and Concrete
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• v.17 no.4
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• pp.455-475
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• 2016

Dynamic characteristics, named as natural frequencies, damping ratios and mode shapes, affect the dynamic behavior of buildings and they vary depending on the construction stages. It is aimed to present the effects of construction stages on the dynamic characteristics of reinforced concrete (RC) buildings considering theoretical and experimental investigations. For this purpose, a three-storey RC building model with a 1/2 scale was constructed in the laboratory of Civil Engineering Department at Karadeniz Technical University. The modal testing measurements were performed by using Operational Modal Analysis (OMA) method for the bare frame, brick walled and coated cases of the building model. Randomly generated loads by impact hammer were used to vibrate the building model; the responses were measured by uni-axial seismic accelerometers as acceleration. The building's modal parameters at these construction stages were extracted from the processed signals using the Enhanced Frequency Domain Decomposition (EFDD) technique. Also, the finite element models of each case were developed and modal analyses were performed. It was observed from the experimental and theoretical investigations that the natural frequencies of the building model varied depending on the construction stages considerably.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.251-258
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• 1998

The purposes of this study was to investigate accuracy and indigenity of landscape plant species in planting design and construction at housing complex and offer basic data for improving precision of planting construction. The scientific name of landscape plant species was described in planting drawings at only two sites among twelve survey sites. According to analysis on indigenity of plant species in planting drawings, it was found that the component ratio of foreign species was the highest and the component ratio of native species at public housing complex was the lowest. The component ratio of landscape plant species in planting construction was severely differed to that of planting drawings. Also the component ratio of cultivar was higher than that of planting drawings due to planting of sevveral cultivars for one species in planting drawings. In the result of accuracy analysis on landscape plant species in planting construction, it was found that mean ratio of inacccurate species was 33.2% at public housing complex, 29.6% at local company housing complex and 26.4% at nationwide company housing complex. It was found that several cultivars were planted for one species in planting drawings. The representative species which were planted by several cultivars were Camellia japonica, Rododendron spp., Prunus spp. and Magnolia spp. and so on. In order to promote the precision and speciality of planting design and construction, scientific and cultivar name of plants should be described in planting drawings.

• Journal of the Korea Institute of Building Construction
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• v.12 no.4
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• pp.401-414
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• 2012

The adoption of Green Frame is expected to provide economic benefits, since construction costs are reduced by the in-situ production of precast concrete column and beam. The cost reduction can ultimately be realized by saving transportation costs and the overhead and profit of PC plants. The cost structure of Green Frame, which is built up using composite precast concrete members, is similar to that of a bearing-wall structure, but the difference in construction process has resulted in some cost differences for a few items. In particular, production and installation is the principal work involved in Green Frame made by precast concrete members, while form and concrete work is the principal work for a bearing-wall structure. As such, the rental time and fee for a tower crane should be compared through time analysis. To verify reliability, this study focused on developed residential projects to estimate the construction costs. Through this analysis, it was found that the costs of Green Frame were 1.57% lower than the costs of bearing-wall structure. The results of this study will help in the development of a management plan for the structural work of Green Frame.

• Journal of the Korea Safety Management & Science
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• v.14 no.3
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• pp.49-57
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• 2012

Proportion of falling from height accident at construction work accounts for more than 40%, and the number of injuries is getting increased. So without considering falling from height, we can say that it's hard to achieve our goal(accident prevention). Another critical point that we have to think about theses days is the fact that construction workers are getting older. To be specific, the number of workers who are above 50 years old accounts for 65.6% among the fatalities(2007~2011, KOSHA inspection). Accordingly, to effectively prevent construction accedents, especially falls from height, we need to focus on motion analysis of older construction workers and then make suitable measures for growing accident rates at construction work.

• Journal of Construction Engineering and Project Management
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• v.2 no.2
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• pp.53-60
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• 2012

Accurate assessment of $CO_2$ emission from buildings requires gathering $CO_2$ emission data of various construction materials. Unfortunately, the amount of available data is limited in most countries. This study was conducted to present the $CO_2$ emission data of concrete, which is the most important construction material in Korea, by conducting a statistical analysis of the concrete mix proportion. Finally, regression models that can be used to estimate the $CO_2$ emission of concrete in all strengths were developed, and the validity of these models was evaluated using 24 and 35MPa concrete data. The validation test showed that the error ratio of the estimated value did not exceed a maximum of 5.33%. This signifies that the models can be used in acquiring the $CO_2$ emission data of concrete in all strengths. The proposed equations can be used in assessing the environmental impact of various construction structural designs by presenting the $CO_2$ emission data of all concrete types.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.8
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• pp.1274-1285
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• 2002

The purposes of this study are to help the authorized textbooks on home economics be selected and used effectively, to provide basic data that are needed to improve the quality of home economics textbooks, and to suggest a next curriculum on home economics. In the study, eight high school home economics textbooks for "6th Curriculum developed by Ministrv of Education and Human Resources Development"were used for the analysis. The results are summarized as follows: there were wide differences in degrees of diversity and accomplishment in the contents of textbooks. In comparison, it was unfolded that three areas, "family", "home resource management" and "consumer" ,occupied much larger portions than other areas. About 81 percent of the authors of home economics textbooks were professors. A contents analysis on the clothing area showed that every textbook includes costume culture, clothing materials, clothing maintenance, and clothing construction. The presentation coverages and relative difficulties of textbooks were, however, diverse. It is somewhat noticeable that, while fewer professors majoring in clothing construction participated in writing, generally more pages were allocated to clothing construction than other areas. While presentations on anthropometrics method, construction theory, draft theory, usage of sewing machine and fitting theory were insufficient most textbooks were dealing with drafting of basic slopers and sewing procedure, etc. Making-up techniques on the apparels items such as Korean traditional men's pants, pajamas, shirt vest skirt, pants, apron and Korean pouch were handled closely in each textbook.

• Journal of the Korea Institute of Building Construction
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• v.14 no.5
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• pp.443-449
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• 2014

Although risk reduction of construction projects have been continued, the risk of fatal accident has been increased. The purpose of this paper is to reduce the cause of the essential risk factors. Questionnaire survey of construction companies in domestic was conducted and the Multiple Regression Analysis of statistics program was used to grasp effective factors among the risk factors of construction companies in domestic. Development of the essential risk factors and its application to projects could lead to improvements such as compression of network, reduction of cost, improvement of quality and reduction of safety accident.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.729-734
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• 2022

Various studies using accident cases are being conducted to identify the causes of accidents in the construction industry, but studies on the differences between public and private construction are insignificant. In this study, web scraping and text mining technologies were applied to analyze the causes of accidents by order type. Through statistical analysis and word cloud analysis of more than 10,000 structured and unstructured data collected, it was confirmed that there was a difference in the types and causes of accidents in public and private construction. In addition, it can contribute to the establishment of safety management measures in the future by identifying the correlation between major accident causes.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.311-317
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• 2007

"Environmentally Sound and Sustainable Development (ESSD)" is a key word in recent years. The construction industry, have put a great influence on ergonomic and sustainable environment. Recently, "green building certifications", such as Indoor Air Quality (IAQ) and eco-friendly material regulation have been established. With this regard, new construction and aged-housing remodeling projects are required to meet these certification criteria. Multi-housing residents have great concern on eco-product, since many cases are reported that Sick Building Syndrome is caused by toxic substance from building materials. Aged-housing remodeling project is very unique in that building residents are selected prior to design phase. Therefore, the analysis of resident's need for building materials in aged-housing remodeling is relatively easy compared to new building construction. As such, it is very important to analyze their preferences for eco-friendly materials prior to project execution. The purpose of this study is to find the needs of residents and priority of their needs. Based on their needs and priority, this paper provides a new strategy in using environment-friendly materials and maximizing their satisfaction level when aged housing remodeling is constructed. In addition, this paper provide new criteria in selecting new developed environmental materials in remodeling projects for the purpose of improving the safety and health level in construction industry.