• Journal of the Korea Institute of Building Construction
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• v.17 no.2
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• pp.175-181
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• 2017

The purpose of this study is evaluating the characteristics of tensile strength of UHPC and examining tensile performance of notched specimens by direct tensile test. For test variables, 120, 150, and 180MPa of target design standard strength were aimed at. With general water curing and $90^{\circ}C$ high temperature steam as curing conditions, the properties were reviewed. Overall, it was represented that the specimens of notch-type direct tensile strength concrete was effective in inducing central cracks compared with existing direct tension specimens. Through this, it was judged that data construction with high reliability was possible. Above all, in a graph of direct tensile strength and strain, in the case of steam curing at high temperature, there was great difference of initial tensile strength compared with water curing. As passing of ages, an aspect that the difference gradually decreased was shown. Maximum tensile strength was found to increase steadily with increasing age for all target design strengths in water curing, in the case of steam curing, the tendency to increase significantly due to the initial strength development effect at 7 days of age. The initial crack strength increases with age in case of underwater curing, in the case of steam curing, it was higher than that of water curing in 7 days, while the strength of 28 days was lowered. In this part, it is considered necessary to examine the arrangement condition of the steel fiber.

• Journal of the Korea Concrete Institute
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• v.18 no.2 s.92
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• pp.275-282
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• 2006

Recently, Fiber Reinforced Polymers(FRP) has been emerged as an alternative material to solve the corrosion of steel reinforcement in reinforced concrete structures. FRP exhibits higher specific strength and lower weight compared to steel reinforcement. Moreover, good resistance to corrosion of the FRP may be useful in aggressive environments causing deterioration such as chloride environment. However, causes for higher initial cost of FRP than that of steel, little information on the long-term behavior of FRP, and brittle failure make the efforts to apply FRP in civil structures slow. Glass fiber among the fibers used to manufacture FRP can be seen as the most beneficial material with regard to initial costs. But its low elastic modulus, which attains barely a quarter of steel, nay thus lead to excessive deflections when used as reinforcement for flexural members. This research was carried out on the tensile properties of hybrid rods made with glass and carbon fibers to improve those of FRP rod made with glass fiber. Parameters were resin type and the arrangement of glass and carbon fibers. The tensile properties of hybrid rods were compared with those of rods manufactured with only glass or carbon fibers. The results indicated that the tensile properties of hybrid rod were good when the carbon fiber was arranged in the core.

• Journal of Environmental Impact Assessment
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• v.23 no.6
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• pp.477-491
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• 2014

The purpose of this study is to develop urban planning for mitigating thermal comfort by analyzing the relationship between various physical environmental factors and radiation fluxes focused on urban areas of Changwon city, Gyeongsangnam-do. Physical environmental factors were analyzed by sky view factor (SVF), land cover and land use types using GIS program. Radiation fluxes were measured upward and downward in solar and terrestrial radiation by mobile measurement during 3 days (2 daytime and 1 nighttime) in summer season. SVF is high in urban park less around buildings. High dense building sites were low. Downward solar radiation fluxes were the highest about $700W/m^2$ at daytime, and decreased in spatial type arranged dense buildings. Upward solar and terrestrial radiations was affected by land cover types that have thermal features such as reflectivity, emissivity, and heat capacity. Therefore, urban space needs appropriate planning with building arrangement, green walls and land cover replacement for mitigating thermal comfort in urban area.

• Journal of architectural history
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• v.5 no.2 s.10
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• pp.25-39
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• 1996

Architectural researches on the traditional houses of Korea have been studied mainly based on the data collected in the field survey. From explosively incresed real mesurements and drawings in the field, plenty of data have been collected. Those have been the basic data for verifing and developing the theories on the traditional house. But after Korean war the researchers in South-Korea were not able to approach to the field in North Korea, so the new data of North Korea were not added any more. The poverty of real data have caused regional unbalance in the researches. This paper aims at collecting new data of traditional house in North Korea. But still being prohibited for the researchers of South Korea to approach to the field, I had to depend on the memories and experiences of the immigrants from North Korea who are now living in Kyon-Nam and Pusan Province. Through the questionnaire and drawings, they described vivid memory of their old houses. I was able to collect the data of 71 cases, which are significant and valuable as much as those of the real field are. The data include the address and site condition, family structure, economic condition, construction period of each house, The drawings by themselves show the building forms and plans, the plans of each building, and the included spaces. Although the quantity of those data is not enough for statistical analysis, it shows general tendency for analizing regional charateristics, the differnces among economical classes, and the periodical change. It opens the way for verfying the existing theory. Analizing the data, I have some conclusions as followings: a. Most of researchers have classified the dominant housing type of Hamkyong-Do as 'the double fold' type. In this study, all cases of Hamkyongbuk-do also show 'the double fold plan with Chongju-kan'. But in Hamkyongnam-do some cases show 'the double fold plan without Chongju-kan, or projecting the stable into the yard, which seem to be different type from 'the double fold plan with Chongju-kan' b. Existing theories classified the dominant housing type of Pyongahn-do as 'two buildings with pararell arrangement'. This classification is verified with the plentiful cases in this study. Futhermore, I found new tendency, that is, getting higher econnomic condition, they construct annex buildings between the main buildings. Finally their houses show 'scattered ㅁ shape'. The houses included in this two types has narrow and closed inner yard, which is different from the houses of the same shape in the south region of Korea. c. Existing theories classified the dominant housing type of Hwanghae-do as 'ㅁ sape with Daechong' type. I found many cases of 'ㅁ shape', but only two cases show 'Daechong'. 'The doble fold' type was also founded. Unfortunately very few cases were sent from Hwanghae-do, it is not enough for finding general tendency.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.6 s.113
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• pp.98-108
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• 2006

The climate of urban area is an unstable type with considerable seasonal variation in precipitation wind speed, and temperature and it grows worse. Besides, ozone is a serious air pollutant in most of large cities. So worldwide, some of large cities are investing in forestry options to offset their climate problems, but lack of information has hindered comparisons of urban un cost effectiveness to other options. This research intends to study the economic benefits of tree shading of 19 parking lots in UCD campus. The economic benefits of tree shading are air conditioning savings, air quality, stormwater run-off, and other benefits. Especially, this study focuses how much the economic benefit of parking lot shading has been increased from 1995 to 2003 year by aerophoto. Some data on dimensions of parking lots and the number, size, tree species, and location of trees around each parking lot was inventoried. Two aerophotos(1995,2003) were used in order to analyze the increasement of tree canopy in 19 parking lots for 8 years. However, increasing coverage of trees and managing them for healthy growth would not be sufficient for avoiding adverse impacts by future climate change. Additional measures should be followed such as an increase of energy use efficiency and development of substitute energy. For example, coverage of trees help to save cooling energy by blocking solar radiation reaching parking cars and building structures through shading, and creating cool micro-climates through evapotranspiration. They also reduce heating demand by decreasing air infiltration and heat conduction out of the interior of buildings. Proper arrangement of vegetation over the parking lots can reduce cooling and heating costs. So proper planting design around hard space paving including species selection and location can significantly save cooling and heating energy. And a reduction in car and building's heating and cooling costs results in the reduction in energy demand which causes to emissions of air pollutants. Total increased tree canopy from 1995 to 2003 is $8,470.45m^2$ and the economic benefits is US$ 5,282.10. The economic benefit of one tree has been US$ 7.21 for 8 years. And an annually increased benefit is US$ 0.9 per a tree. If this kind of study is applied to studying the economic benefits of tree canopy in parking lots of Korea, it could result in guidelines of tree planting of parking lots. Because the trees selected for planting in parking lots were not suitable for an environment, the guidelines should contain a recommended list of trees. The guidelines should propose the shading percentage of parking lot when we plan a parking lot and contain the maintenance of trees in order to maximize the economic benefits of tree canopy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.32-41
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• 2017

This study examined the arrangement attribute of each component based on the relationship among the components using space syntax at the entire complex level when analyzing the outdoor space of an apartment complex in Cheonan and as a preliminary study. The accessibility change in the access space to each space and to the facilities were examined based on a resident walking in the perspective that the outdoor spaces of the apartment complex are one spatial structure connected together. The space was divided into a total of 5 periods and the access space to the facilities and spaces located in outdoor space of the apartment complex were established as the unit space. In this study, a total of 6 analysis items were established: main complex access space, main building access space, shopping mall within complex, control office/center for senior citizens, children's playground, and resident sports facilities. In the analysis, the following conclusion was obtained. First, the accessibility to the main complex access space was high over almost all periods and the main building access space generally showed low accessibility. Second, the shopping mall showed a tendency that the closer the period, the more the accessibility is increased. Third, the control office/center for senior citizens, which can be considered as a common resident space and the children's playground out of the resident sports facilities, showed an exceptional tendency, the integration order was constantly high without a large change by the period and the control office/center for senior citizens showed the tendency for a high integration order, indicating that it is planned mainly in a location with good accessibility.

• Journal of the Korean Wood Science and Technology
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• v.35 no.3
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• pp.61-69
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• 2007

The building materials used for improving indoor air quality, the wood charcoal mixed with cement mortar or natural water paint were examined for their potential removing ability of formaldehyde. After the reaction of samples with formaldehyde in the glass flasks designed in our lab, the remaining formaldehyde was collected using DNPH (2,4-dinitrophenyl hydrazine) cartridges, and their concentration was determined using HPLC. From the results, it was found that the removing amount of formaldehyde per one gram sample containing 5, 10, or 15% of wood charcoal was more than three times compared to that of control (100% cement mortar or water paint). Their elimination percentages from the initial formaldehyde was about 80~90%. The experimental results for wood charcoal-water paint showed a similar trend with those of wood charcoal-cement mortar samples. Their elimination percentages from the initial formaldehyde was about 90%. It is proposed that formaldehyde is adsorbed on the adsorbed 'O' or 'OH' groups in the graphene layers formed through the re-arrangement of lignocellulose in the wood during the carbonization procedure.

• Journal of Radiation Protection and Research
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• v.40 no.2
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• pp.92-100
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• 2015

For the purpose of improving the efficiency of the radiation impact assessment of dry interim storage facilities for the spent nuclear fuel of pressurized water reactors (PWRs), radiation impact assessment was performed after the application of sensitivity assessment according to the radiation source term designation method, development of a 2-step calculation technique, and cooling time credit. The present study successively designated radiation source terms in accordance with the cask arrangement order in the shielding building, assessed sensitivity, which affects direct dose, and confirmed that the radiation dosage of the external walls of the shielding building was dominantly affected by the two columns closest to the internal walls. In addition, in the case in which shielding buildings were introduced into storage facilities, the present study established and assessed the 2-step calculation technique, which can reduce the immense computational analysis time. Consequently, results similar to those from existing calculations were derived in approximately half the analysis time. Finally, when radiation source terms were established by adding the storage period of the storage casks successively stored in the storage facilities and the cooling period of the spent nuclear fuel, the radiation dose of the external walls of the buildings was confirmed to be approximately 40% lower than the calculated values; the cooling period was established as being identical. The present study was conducted to improve the efficiency of the Monte Carlo shielding analysis method for radiation impact assessment of interim storage facilities. If reliability is improved through the assessment of more diverse cases, the results of the present study can be used for the design of storage facilities and the establishment of site boundary standards.

• Journal of the Korean Home Economics Association
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• v.31 no.1
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• pp.225-239
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• 1993

The purpose of this study is to look for the basic formative elements of housekeeping space of our cultural life which are worthy to succeed and develop by revaluating in modern view and to reveal what we should maintain form the women's view of the housework in those days. In this study, out look on Chosun Dynasty housekeeping is based on the norm of the women in those days. The research on the housekeeping space for norm of the women in those days. the research on the housekeeping space for Chosun Dynasty upperclass is focused on the house built from early till late Chosun Dynasty, which is now a cultural asset. As a result, norm of Chosun Dynasty have created a social wide atmosphere for women to devote herselves to the housekeeping. Moreover the constructions of Chosun Dynasty's upperclass are affected by Korea's natural environment and socio-cultural environment. Primary factors for natural environment are building materials and the change of seasons. Because of changeable seasons, there were places for storing massive commodities. The other primary factors for socio-cultural environment affecting housekeeping space were social positions, and extended family system, worshipping the ancestors standard of living, the theory of“Poong Soo”(風水, a kind of geomancy) and thought of“Yin and Yang, Five Elements”(陰陽五行) and popular belief of that time. Affected by these two environments, the characteristics of housekeeping space for Chosun Dynasty are ; the main building of the house was used as a diverted area for women to work, and was reconstructed for household affairs. There were inefficient points in the housekeeping space of that time and the space remained stagnant because of the restricted sex and the social position of housekeeping doer. But you could find some points that are efficient and functional to adjust in those living conditions. The storehouse, storage barn, shed and soyjar terrace are the specialized storing place, according to the kinds and characteristics of the commodities. the kitchen, for example, is the combinations of many abilities. It is not only for cooking or heating the room, but also for storing drinking water. The hall which was the storing place, housekeeping place and also the place for family events are used as a diverted place. The linked arrangement of kitchen, store house, boudoir and the other rooms. In addition, we can see that the construction of the kitchen for more than tow people could work in.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.36 no.2
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• pp.13-24
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• 2020

This study derives the characteristics of the private external space planning in multi-family housing through the analysis of the good case built after 2000 in Europe. First, the cases were categorized into block or block perimeter, linear and point type to examine the relationship between the type of building in urban context and the location of private external space. By block or block perimeter and linear type, private external spaces are planned in the inner courtyards or open space between buildings used as common space for residents, inducing communications between neighbors. And the direction of private external space depends on the arrangement of the building mass in urban context. In the classification as point type, there are many cases, where private external spaces are arranged in all directions, connected almost all interior spaces. Second, based on the above results, the planned characteristics of the private external space are derived by dividing it into three categories: intermediated space between inside and outside, intermediate space between private and public /individual and collective space and the identity of the intermediate space. (1) In most cases, direction, size of enclosed area and location of private extern space is designed to fit the surrounding context, so residents can perceive as much of the assets of the surrounding environment as possible, and it can be used as an extended area of living space. In another cases, it is divided into various sub-areas to experience the spatial transition from inside to outside or vice versa. 2) The private external space, which is placed in a courtyard or in a collective open space, is partially enclosed and blocked, allowing interaction with the neighbors without pressure. Along the street, they are designed to allow residents to experience the vitality of the city and to be formative element of the facade, which could confidently reveal the lifestyle and taste of residents. 3) By some of point types, which facade is three-demensional layer as a habitable external space, the private external space is very flexible for use. This intermediate space is composed of diverse spaces for various needs, or it has generous size with positional conditions connected with all interior spaces to be used multi-functional.