• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.4
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• pp.201-208
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• 2011

Objectives: According to the compliance of the asbestos-related regulation, every building has to be inspected for asbestos presence before its abatement work. This study was performed for identifying the types and contents of asbestos in building bulk samples. Materials and Methods: Bulk samples were collected during the asbestos inspection in 2010. We grouped the bulk samples into the regulated asbestos containing materials(RACM), presumed asbestos containing materials(PACM), and construction products. Additionally, the types of asbestos in all bulk samples were identified by polarization microscopy(PLM). Results: The RACMs were from building, house, pipe and facility. The RACMs were found mainly building (72.1%) and house (93.7%). The contents of chrysotile in building, house and facility were 66.9% (1-90%), 89.7% (2-90%) and 11.0% (2-90%), respectively. PACMs were surfacing material, thermal system insulation (TSI), and miscellaneous material. The miscellaneous materials that showed a high detection rate (79.2%) were ceiling, roofing and wall materials. Among them, the roofing materials had high chrysotile content(9.7%, 2-21%), followed by wall (8.7%, 2-21%) and ceiling (3.4%, 1-17%). In the construction products, asbestos was found mainly in slate (92.6%, 2-21%), including chrysotile. The slate had high asbestos content (9.7%, 2-21%), followed by cement flat board (8.7%, 2-19%) and textile (3.4%, 1-17%) Conclusions: Utilizing these results, it would be contributed to construct a useful ACM database and prevent from asbestos exposure to workers in the asbestos abatement and maintenance works.

• Journal of the Korea Institute of Building Construction
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• v.14 no.6
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• pp.515-522
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• 2014

In order to quantitatively evaluate the effect of fly ash (FA) as partial replacement of cement on the life-cycle environmental impact of concrete, a comprehensive database including 4023 laboratory mixes and 2120 plant mixes was analyzed. The environmental loads on the life-cycle assessment were quantitatively converted into environmental impact indicators through categorization, characterization, normalization and weighting process. The life-cycle environmental impacts of concrete could be classified into three categories including global warming, photochemical oxidant creation and abiotic resource depletion. Furthermore, these environmental impacts of concrete was decreased with the increase of the replacement level of FA and governed by the unit content of ordinary portland cement (OPC). As a result, simple equations to assess the environmental impact indicators could be formulated as a function of the unit content of binder and the replacement level of FA.

• Journal of IKEEE
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• v.22 no.2
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• pp.274-280
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• 2018

In this paper, we have developed the vacuum infusion automation system for the safety and quality advancement of the boat. It is necessary for the precise mixing rate of resinoid and curingagent to inject in an inner ship and deck at short time. We need for the optimal condition to a strengthen construction of boat. This one can solve the post deformability of the strengthen structure and can control the precise mixing rate of resinoid and curingagent to the resinoid fluidity and flowing rate per time. Under these condition, we can advance the an quality construction that based on the model and database information of the boat. Also, we can have an effective process management and retrench the production cost.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.4
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• pp.488-495
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• 2017

In this study, we conducted the kinetic hydration modeling of OPC and the final product according to the substitution ratio of GGBS by using the geochemical code, GEMS, in order to calculate the thermodynamic equilibrium. The thermodynamic data was used by GEMS's 3rd party database, Cemdata18, and the cement hydration model, the Parrot & Killoh model was applied to simulate the hydration process. In OPC modeling, ion concentration of pore solution and hydration products by mass and volume were observed according to time. In the GGBS modeling, as the substitution rate increases, the amount of C-S-H, which contributes the long-term strength, increases, but the amount of Portlandite decreases, which leads to carbonation and steel corrosion. Therefore, it is necessary to establish prevention of some deterioration.

• Journal of Korean Society for Geospatial Information Science
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• v.13 no.4 s.34
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• pp.19-25
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• 2005

This study suggests a method for securing road safety by extracting the expected surface freezing section in planning a route using GIS. When planning a road construction in a mountainous area it is possible to confront surface freezing especially in the wintertime. In addition, it is required assessment data of surface freezing rates in the case of turnkey inspections of newly constructed or expanded roads. Consequently, an analysis method that can quantitatively estimate the surface freezing section and sunshine influence on each section of a road is needed. We can extract the expected surface freezing section which amounted to around 29km of the Donghae highway, with such techniques as three-dimensional modeling, sunshine simulation geographical database construction and spatial analysis using the overlay function of the GIS spatial analysis. This study can be used as a method to assess advance safety which has a direct influence on planning the blueprint that should be approved by a policy maker after efficiently understanding the expected surface freezing section in accordance with hill shade.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.93-105
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• 2006

The construction of golf courses has had adverse effects on the natural landscape and delicate ecosystem of Korea. Efficiency in planning and design was necessary to minimize the environmental impact of the original construction. However, the ordinal design methods have limited the data processing by the massive scale of the project of golf course development. Conventional design methods did not have a proper tool for alternative plans on pre-estimation of landscape destruction or minimizing of the environmental impact. Therefore, advanced computerized techniques need to be adapted for golf course design to solve the problems concerning the environmental impacts. Geographic information system (GIS) was applied on the process of geographical data input and analysis through the final outputs. Simulation works by the total database management enable the pre-investigation of the design In view of an assessment of environmental impacts. It is also possible to evaluate plans easily and propose the alternatives properly. Precise quantity calculation of engineering works by computer system should be guaranteed scientific, economic, and environmentally-sound.

• Journal of the Korea Concrete Institute
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• v.24 no.5
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• pp.597-604
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• 2012

The present study assessed the $CO_2$ emissions of concrete according to the type and replacement ratio of supplementary cementitious materials (SCM) and concrete compressive strength using a comprehensive database including 2464 cement concrete specimens and 776 cement concrete mixes with different SCMs. The system studied in $CO_2$ assessment of concrete based on Korean lifecycle inventory was from cradle to pre-construction, which includes consistent materials, transportation and production phases. As the performance efficiency indicators, binder and $CO_2$ intensities were analyzed, and simple equations to evaluate the amount of $CO_2$ emission of concrete were then formulated as a function of concrete compressive strength and the replacement ratio of each SCM. Hence, the proposed equations are expected to be practical and useful as a guideline to determine the type and replacement ratio of SCM and unit content of binder in concrete mix design that can satisfy the target compressive strength and $CO_2$ reduction percentage relative to cement concrete.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.4
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• pp.64-75
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• 2008

Since the current database systems for managing geotechnical investigation results were limited by being described boring test result in point feature, it has been trouble for using other GIS data. Although there are some studies for spatial characteristics of subsurface modeling, it is rather lack of being interoperable with GIS, considering geotechnical engineering facts. This is reason for difficulty of practical uses. In this study, we has developed subsurface spatial information model through extracting needed geotechnical engineering data from geotechnical information DB. The developed geotechnical information clustering program(GEOCL) has made a cluster of boring formation(and formation ratio), classification of layer, and strength characteristics of subsurface. The interpolation of boring data has been achieved through zonal kriging method in the consideration of spatial distribution of created cluster. Finally, we make a subsurface spatial information model to integrate with digital elevation model, and visualize 3-dimensional model by subsurface spatial information viewing program(SSIVIEW). We expect to strengthen application capacity of developed model in subsurface interpretation and foundation design of construction works.

• Journal of the Korean Society for information Management
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• v.31 no.4
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• pp.69-102
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• 2014

In this study, we propose an approach of building a portal site that can offer integrated services for textbook through special libraries For this purpose, we analyzed previous related studies and investigated textbook portal construction sites domestically and abroad. Based on this research, we developed survey questions and conducted a survey targeting users of textbook libraries. As a result, the following projects are required for creating a textbook library: a comprehensive list of textbooks and other content construction, digitization projects of library holdings, collection and delivery of various textbook-related reference books, building a textbook database by topic, collecting and providing textbook-related research publications, a cooperation network with textbook-related organizations, and active promotion of portal sites.

• Journal of Korean Society of Steel Construction
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• v.16 no.5 s.72
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• pp.683-694
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• 2004

Advanced analysis and optimal design of semi-rigid space steel frames were presented. The advanced analysis can predict the combined nonlinear effects of connection, geometry, and material on the behavior and strength of semi-rigid frames. The Kishi-Chen power model was used to describe the nonlinear behavior of semi-rigid connections. Geometric nonlinearity was determined using stability functions. Material nonlinearity was determined using the Column Research Council (CRC) tangent modulus and the parabolic function. The direct search method proposed by Choi and Kim was used as optimization technique. One by one, the member with the largest unit value evaluated using the LRFD interaction equation were placed adjacent to a larger member selected from the database. The objective function was assumed to be the weight of steel frame, while the constraint functions were load-carrying capacities, deflections, inter-story drifts, and the ductility requirements. The member sizes determined using the proposed method were compared to those derived from the conventional LRFD method.