• Journal of the Korea Concrete Institute
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• v.28 no.3
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• pp.329-340
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• 2016

Increase in demotion and repair works on buildings in the construction market generates a large amount of construction waste. Recycling of construction waste is important for saving of resources, preservation of environment and constant advance of the construction industry. Accordingly, the environmental and economic value of recycled aggregate, which is produced after waste concrete is crushed, is increasingly highlighted. It is generally known that compared to concrete made of ordinary aggregate, concrete made of recycled aggregate has low quality, and the low quality is dependent on the amount of the bonding heterogeneous (cement paste and mortar) as well as the amount of the pores within the bonding heterogeneous. Reports on carbonation mechanism shows that the pores of cement-based materials are filled up by the progress of carbonation. Therefore, this study aims at an estimation of the period for optimum carbonation reforming appropriate for the thickness of the bonding heterogeneous of recycled aggregate, based on carbonation mechanism, with a view to improving the product quality by means of filling up the pores of the bonding heterogeneous of recycled aggregate. This study drew the carbonation depth according to the passage of age by calculating the bonding ratio and bonding thickness of the bonding heterogeneous as against the particle size distribution of recycled aggregate as well as by chemical quantitative analysis according to the age of accelerated carbonation of mock-up samples imitating bonding heterogeneous. Based on the correlation between the age of accelerated carbonation and carbonation depth, this study also proposed the estimated period of carbonation reforming of recycled aggregate appropriate for the thickness of the bonding heterogeneous.

• Journal of Environmental Impact Assessment
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• v.9 no.3
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• pp.229-238
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• 2000

Muju Resort Development environmental impact statement(EIS) in Mt. Teogyu National Park are evaluated with the results of post-environmental evaluation. Three EIA items (ecosystem, hydrology, landuse) are investigated. In terms of ecosystem and hydrology, the environment during construction period was compared with post-construction and it was also true of hydrology section. The land use surrounding the resort area have been changed seriously, and the wildlife in large patch are endangered with the fragmentation by road and resort construction. The three items in the Muju Resort EIS was not assessed properly. So, in order to assess properly accurate data, appropriate approach, and periodical post evaluation are required.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.39-40
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• 2017

This study aims to evaluate the humidity control performance of low-priced generic ceramic panels that are used to control humidity. Temperature and humidity are monitored by using 'Living Lab' and the change of indoor relative humidity is measured and analyzed. According to the results of the study, the indoor relative humidity of rooms installed with ceramic panels was found to be low compared to that of living rooms by 2.2%RH (test period) and 3.2%RH (daily). In the case of maximum relative humidity, rooms installed with ceramic panels were found to be low by 6.9%RH. The results are attributable to the humidity absorption of ceramic panels. Accordingly, future ceramic panels need the improvement of performance and an appropriate construction area should be derived depending on indoor space.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.249-258
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• 2007

Recently orders of projects in the field of oil and gas plants have increased due to rising oil prices and consumption. The markets of oil and gas plants are expanding into the Middle East area and all over the world. Because the oil and gas markets have a lot of overseas construction operations, competition among advanced companies is more important. However, companies in the period of growth have not had enough competitive powers of license in the design phase. Therefore, they are faced with difficulty of adopting the technology which is maximizing the effect of investments, and scheduling of a long-range plan. In order to achieve adequate technology management and competitive power, this study considers a long-range plan through an analysis of an appropriate introduction and the strategic planning process of technology management.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.705-708
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• 2005

In the case that construcion period is delayed because of the force majeure such as a typhoon or a flood, the owners in general should compensate the damages caused by those. But with exception the weather worsening of ordinary level is paid by contractors, while that of exceptional level by the owners. It is critical that it is difficult to distinguish objectively between ordinary and exceptional level weather worsening. Although the term of "ordinary" itself is too abstractive, we can reduce the disputes between owners and contractors by setting the appropriate and objective standard of distinction. For example in the case of rainfall it may be the standard of distinction whether the days of actual rainfall exceed those of average rainfall or not. If the days of actual rainfall don't exceed those of average rainfall contracters should pay the damages because it is distinguished with a ordinary level weather worsening. Besides the standard of distinction in another weather worsening such as severe cold/hot, strong wind etc. which have a effect on delaying the term of works could be settled as a similar model.

• Journal of the Korea Institute of Building Construction
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• v.7 no.4
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• pp.153-159
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• 2007

Recently, as a result of the economic growth, the concentration of population towards the cities and the rise in land prices, the demand for high rise buildings has increased significantly, the trend to build high rise buildings such as the mixed-use development buildings by the domestic construction companies continues. It's very important what kind of form work system is applied on the Core Wall of the high rise buildings to determine the economic efficiency for the whole project. That's because the appropriate selection of the Formwork system enables the construction cost lower, makes the good quality of the finished concrete, reduces the construction period, assurance of safety, and further more, it enables to achieve the successful performance of the projects. Therefore, this research, after comparing the strength and the weakness between the construction methods, focus the point to provide a builder the basic data to choose the right Formwork method.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1559-1563
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• 2009

Despite the serious lack of parking lots, studies on parking lot expansion are insufficient; research on users' satisfaction following parking lot expansion is practically nonexistent. Therefore, this study sought to provide basic data for the parking lot expansion of old apartments by comparatively analyzing users' satisfaction before and after the parking lot expansion through a questionnaire survey that targeted residents benefiting from the expanded parking lot. Results revealed a low post-occupancy satisfaction with the parking lot expansion despite the parking lot expansion and improvement of the parking lot environment. This was because the parking lot was not expanded up to the second basement floor due to the lack of appropriate parking space. Other factors included the construction cost burden and lack of connectivity of the basement parking lot with elevators. The results actually raise the need for the establishment of an optimally suitable expansion plan and development of method and technology requiring lower cost and shorter construction period in the design and construction processes for parking lot expansion. Through post-occupancy evaluation (POE) after parking lot expansion, this study quantitatively identified the problems associated with the parking lots of old apartments and ensuing expansion effects. The findings in this study can be used as basic data to seek a suitable diagnosis and evaluation method for the parking lots of old apartments.

• Journal of the Korea Institute of Building Construction
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• v.11 no.2
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• pp.136-144
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• 2011

The form-work operation of concrete structures is a major element determining the period and cost of construction projects. However, the selection of the appropriate form-work system is dependent on the experience of the site personnel only. In this paper, existing methods (Aluminum form, Sky deck) and new slab form-work methods (AFB: Aluminum panel Form with dropping Beam) were selected. Each method was estimated by means of Delphi techniques based on the qualitative analysis data. This paper suggests an evaluation methodology of slab form-work application in construction sites by calculating qualitative evaluation scores. The methodology finding quantified scores of qualitative criteria can be available to be applied to other construction operation evaluation methods.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.4
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• pp.104-113
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• 2012

This study aimed to find out the improvement plan through analyzing the perception of the expert group engaged in landscape architectural construction and to focus on analyzing the expert groups' experience on Landscape Construction Defects (LCD), defect liability, warranty period, and implementation of the defect liability. The results are as follows: 1. Regarding the experience on the LCD, landscape construction contractors were an awareness of the LCD issue at a serious level, while public-sector clients recognize moderately the LCD issue; and on the first priority in defect implementation, landscape construction contractors considered repair cost while public-sector clients value the identifying causes of defects. 2. In disagreement on the defect liability, landscape construction contractors attributed it to client's lack of responsibility for maintenance while public-sector clients ascribed it to the absence of dealing a criteria with LCD, and regarding the appropriate defect implementation, public-sector clients preferred the following objective by dealing the criteria with LCD while landscape construction contractors advocates by sharing the responsibilities for dealing with LCD based on the identified causes of construction defects. 3. Regarding the warranty period, the public-sector clients considered the 2-year warranty period as appropriate while landscape construction contractors considered it comparatively long, and concerning the commencement of defect warranty period, the public-sector clients viewed it as it should commence to cover the overall completion of the construction while landscape construction contractors perceived it to start on the completion of each work. 4. As for the improvement of the defect implementation system, public-sector clients considered it necessary to establish the objective dealing the criteria with LCD while landscape construction contractors viewed the legislation of maintenance duty. Also, with regard to the important value in establishing and dealing the criteria with LCD, public-sector clients pointed out the objective of the criteria for determining the defects per work type while landscape construction contractors suggested client (user)'s maintenance duty. Because of research, because the system in dealing with LCD is an absence of LCD management agency and dealing the criteria with LCD, it is needed to establish an LCD management agency and make the system in dealing with LCD.

• Journal of Korea Multimedia Society
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• v.10 no.6
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• pp.754-759
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• 2007

Methodology of ontology building based on Web resources will not only reduce significantly the ontology construction period, but also enhance the quality of the ontology. Remarkable progress has been achieved in this regard, but they encounter similar difficulties, such as the Web data extraction and knowledge acquisition. This paper researches on the characteristics of ontology construction data, including dynamics, largeness, variation and openness and other features, and the fundamental issue of ontology construction - formalized representation method. Then, the key technologies used in and the difficulties with ontology construction are summarized. A software Model-OntoMaker (Ontology Maker) is designed. The model is innovative in two regards: (1) the improvement of generality: the meta learning machine will dynamically pick appropriate ontology learning methodologies for data of different domains, thus optimizing the results; (2) the merged processing of (semi-) structural and non-structural data. In addition, as known to all wetland researchers, information sharing is vital to wetland exploitation and protection, while wetland ontology construction is the basic task for information sharing. OntoMaker constructs the wetland ontologies, and the model in this work can also be referred to other environmental domains.