• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.522-526
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• 2010

Heat storage application techniques can be categorized into the sensible heat storage and the latent heat storage according to the method of heat storage. Heat storage is the way of saving remaining heat when heating and cooling loads are light, and then using it when the heating and cooling loads are heavy. Latent heat storage is defined as the method of saving heat by using substances which have high potential heat when phase change is in the range of a certain temperature and when heat storage space is small, compared to those of sensible heat storage and it is possible that absorption and emission of heat at a certain temperature. This study is conducted to save energy when either air-conditioning or heating is operated in a building. We have tried to find out the essential properties of matter and the optimum mixing rate about cement and gypsum for building materials, which have been widely used for proper phase change materials (PCM), when thermal environment property is applied. So we obtained the result of the cooling delay effect about 19% with heat storage mortar containing 3 wt% of PCM.

• Korean Journal of Construction Engineering and Management
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• v.14 no.5
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• pp.3-11
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• 2013

The government has made a lot of efforts to realize 'low-carbon green growth', one of the national policy agendas, throughout the whole industries. The construction sector is not an exception, and technological developments are active to reduce energy consumption and greenhouse gas emission. In particular, buildings occupy more than 20% of the total national energy consumptions. Thus, it can be said that increasing energy efficiency of the residential buildings and reducing CO2 emission are the urgent national agenda. Moreover, as ordinary people find it more and more difficult to get a lease on housing, which has become an important social issue recently, a housing production system that can actively respond to market demands is in urgent need. To build an eco-friendly system that can maximize efficiency in construction, this study attempts to examine and analyze the modular housing production system in the county and to find its problems. By suggesting the ways to improve the system, it aims to prepare for the base to revitalize the unit modular housing production system.

• Journal of the Korean association of regional geographers
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• v.16 no.4
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• pp.387-399
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• 2010

This study, using Fractal theory, aims to examine the meaning in the aspect of urban spatial structure by reflecting the characteristics of elements organizing the urban space and at the same time measuring the urban form quantitatively. By calculating Fractal Dimension to Cheongju as a target, it conducted comparison and analysis by dividing building and road which are internal element of a space into the whole city and urbanized area to compare and analyze validity of the theory application and the inside of an actual urban space. For the method of an analysis, it calculated Fractal Dimension by linking a digital map including the property of building and road with GIS program and using box counting. An analysis result showed that the result value of Fractal Dimension by structure and road is all high and similar. It drew a similar result value from the whole Cheongju and the urbanized area as well, but commercial and industrial area showed low result value from the partial viewpoint. However, it is correct to regard these spaces as one space because they are intimately connected with a residential area. From the general viewpoint, it could be said that Cheongju's Fractal Dimension grows in the context of a urbanized area.

• Korean Journal of Construction Engineering and Management
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• v.14 no.1
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• pp.124-132
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• 2013

An influx of the population to the city has soared due to industrialization. As times go by, cities become densely populated so Korean government started to construct a number of buildings including apartment housings. Because they have become functionally, structurally, esthetically deteriorated over the past two decades. some improvements are needed. There are mainly two ways to improve old buildings: remodeling and reconstruction. Between the two, the first one is more popular as it is less time-consuming and more eco-friendly. Demolition work comes first for both of them and it should not give negative effects since it is regarded as a CP(Critical path) in the overall process. For this reason, a thorough construction management must be done. The reality, however, demolition is managed by the construction manager's experiences and decisions. If the key factor of demolition which is the planning of manpower and machine equipment, is determined by unscientific and subjective judgments, its period and risk also will increase. In particular, eco-friendly demolition can be more risky because it's been rarely conducted. Therefore, scientific and objective ways of demolition management are needed. In this context, this paper aims at analyzing productivity in each process of demolition focusing on manpower and machinery equipment which are the main parts of demolition assuming that the demands of eco-friendly remodeling demolition projects will be increasing. At the same time, by estimating working period through the output, this paper would be helpful to set up the plans for overall project in earlier stage.

• Applied Chemistry for Engineering
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• v.10 no.4
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• pp.592-598
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• 1999

Exterior finishing materials of artificial stones are manufactured with the mixture of water, cement, stone powder and light-weight aggregate. In this research, we tried to find a way of increasing the physical properties and decreasing the manufacturing cost of artificial stone. So, we used ${\beta}$-NSF base surfactant and vinsol base surfactant to the artificial stone mixture instead of light-weight aggregate. The optimum dosage of the ${\beta}$-NSF and vinsol surfactants for artificial stone are found to be 1.0 wt % of cement, respectively. The physical properties increased ca. 20% and the durability for freezing & thawing of the new artificial stone increased ca. 300%. While the manufacturing cost of the new artificial stone decreased as much as 30%.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.570-574
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• 2010

The main function of conventional insulation materials is only to block the heat transfer and reduce heat loss from the building. On the other hand, thermal storage materials can work as an energy saver by absorbing or emitting heat within a specific temperature range. Thermal storage materials for building can maintain a constant temperature by effectively regulating the cycle of indoor temperature. As a result, we can enhance the performance of a cooling and heating system efficiently. In this study, phase change materials (PCMs) were added as thermal storage materials into gypsum boards which are extensively used for building material and we found out the thermal environmental characteristics. In addition, we checked out some problems when applying the thermal storage materials to buildings. Finally, This study set out to examine the degree of environmental-friendly characteristics of thermal storage building materials by analyzing the amount of TVOC and HCHO contents with the possibility of pollutants emission.

• Applied Chemistry for Engineering
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• v.24 no.6
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• pp.579-586
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• 2013

The shortage of fossil fuel and problem of greenhouse gas exhaustion drive the production of biopolymer in a environment-friendly manner. Polyurethane is a polymer formed by reacting an isocyanate (-NCO) with a polyol (-OH) to form urethane link (-NHCOO-). Polyurethane is one of the most widely used polymers in automobile, construction and chemical industries. Two monomers for the polymerization of polyurethane, polyols and isocyanates, can be produced from renewable biomass such as plant oil, cellulose, lignin and etc. Biopolyol production from plant oil has already been implemented in commercial-scale production. In this paper, recent progresses on bio-based approaches on the production of biopolyols, bio-isocyanates and bio-substituent or isocyanate from bio-feedstock are reviewed alongside polymerization and characterization of biopolyurethane for industrial applications.

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.291-295
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• 2011

A bake-out process using auto switchgear for five days was performed to evaluate the reduction effect of the concentration of volatile organic compounds (VOCs) and formaldehyde in a newly-built elementary school gymnasium. Reduction rates of VOCs were observed as followings: 38.2, 64.2, 86.3, 80.2, and 71.5% for benzene, toluene, ethylbenzene, xylene, and styrene, respectively, which satisfies the indoor air quality standards of newly-built apartment houses in Korea. The reduction rate of total VOCs and formaldehyde were 67.0 and 24.7%, respectively. Those results proved that the bake-out process using auto switchgear was effective for reducing indoor air pollutants.

• Archives of design research
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• v.14
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• pp.209-219
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• 1996

The BAUHAUS started as the purpose of training the people who are designers in the industnal society or who have artistic talent as architect, handicraftman, sculptor, and in the construction, it was based for entire organizational training for every handicrafts in the aspect of the art and form. The preliminary course that became the generative power of the human training that have possessed creativity was studied and put in to practice through the formative activity of dIverse form and method according to the educational idea and the educational method of the teachers who are in charge of such edudation, and common access method that forms the fundamental basis was centered not only human being as a formative principle, and analyzed thoroughly with biological function and further until mental and philosophical part but served and thought synthetically and took principal objects at the formative practice. Together with this, the characteristic structure of the BA UHA US's formative education was taking the grouptherapy educational method where there was not distinguish teacher and student and through the liberal criticism and they realize by experience themselves that how to solve the certain subject and pursue the form by compare each other's solutions.

• 대한공업교육학회지
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• v.43 no.1
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• pp.1-19
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• 2018

As the BIM designing technology has been applied recently in the construction field, architectural design education in the field of work and university has been changing to 3D modeling. Nevertheless, architectural design & drafting education in the construction specialized vocational high school is not responding appropriately to change. Despite the fact that students need to have 3D modeling design ability, there is a very lack of 3D housing design instructional material that can satisfy the change. The purpose of this study is to develop BIM-based 3D modeling instruction material and apply to analyze effect on interest and task performance ability on Housing Design. The 3D modeling instruction material used in this study was developed through four stages of preparation, development, implementation and evaluation according to the PDIE model procedure. Also, the experimental design model for hypothesis testing was used nonequivalent control group pretest-posttest design. Based on the experimental design model, BIM-based 3D modeling instruction material was performed in the experimental group and 2D CAD-based standard instruction material was taught in the control group. Experimental treatment was conducted on the students of construction specialized vocatinonal high school, and applied to the subject of Professional Drafting in the 12 hours. Before and after the experimental treatment, the interest and task performance ability on Housing Design were tested. Based on the test results, we analyzed the effects of the 3D modeling instruction material through the independent samples t-test. The results of the study are as follows. First, BIM-based 3D modeling instruction material was developed of 'Housing Design & Drafting' unit on the subject of Professional Drafting in construction specialized vocational high school. Second, the application of 3D modeling instruction material has shown to be effective in improving students' interest. Third, the application of 3D modeling instruction material has shown to be effective in improving students' task performance ability on Housing Design.