• Journal of odor and indoor environment
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• v.17 no.4
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• pp.355-361
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• 2018

Mold grows more easily when humidity is higher in indoor spaces, and as such is found more often on wetted areas in housing such as walls, toilets, kitchens, and poorly managed spaces. However, there have been few studies that have specifically assessed the level of mold in the indoor spaces of water-damaged housing in the Republic of Korea. We investigated the levels of airborne mold according to the characteristics of water damage types and explored the correlation between the distribution of mold genera and the characteristics of households. Samplings were performed from January 2016 to June 2018 in 97 housing units with water leakage or condensation, or a history of flooding, and in 61 general housing units in the metropolitan and Busan area, respectively. Airborne mold was collected on MEA (Malt extract agar) at flow rate of 100 L/min for 1 min. After collection, the samples were incubated at $25^{\circ}C$ for 120 hours. The cultured samples were counted and corrected using a positive hole conversion table. The samples were then analyzed by single colony culture, DNA extraction, gene amplification, and sequencing. By type of housing, concentrations of airborne mold were highest in flooded housing, followed by water-leaked or highly condensed housings, and then general housing. In more than 50% of water-damaged housing, the level of airborne mold exceeded the guideline of Korea's Ministry of Environment ($500CFU/m^3$). Of particular concern was the fact that the I/O ratio of water-damaged housing was greater than 1, which could indicate that mold damage may occur indoors. The distribution patterns of the fungal species were as follows: Penicillium spp., Cladosporium spp. (14%), Aspergillus spp. (13%) and Alternaria spp. (3%), but significant differences of their levels in indoor spaces were not found. Our findings indicate that high levels of mold damage were found in housing with water damage, and Aspergillus flavus and Penicillium brevicompactum were more dominant in housing with high water activity. Comprehensive management of flooded or water-damaged housing is necessary to reduce fungal exposure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.2
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• pp.810-818
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• 2021

A leakage current of ESS is classified mainly by the occurrence from a PCS(Power Conditioning System) section and an unbalanced grid current. The reason for the leakage current from the PCS section is a voltage change by IGBT (Insulated Gate Bipolar Transistor) switching and stray capacitance between the IGBT and heatsink. The leakage current caused by the grid unbalanced current flows to the ESS through the neutral line of grid-connected transformer for the ESS with a three limb iron type of Yg-wire connection. This paper proposes a mechanism for the occurrence of leakage current caused by stray capacitance, which is calculated using the heatsink formula, from the aspect of the PCS section and grid unbalance current. Based on the proposed mechanisms, this study presents the modeling of the leakage current occurrence using PSCAD/EMTDC S/W and evaluates the characteristics of leakage currents from the PCS section and grid unbalanced current. From the simulation result, the leakage current has a large influence on the battery side by confirming that the leakage current from the PCS is increased from 7[mA] to 34[mA], and the leakage current from an unbalanced load to battery housing is increased from 3.96[mA] to 10.76[mA] according to the resistance of the housings and the magnitude of the ground resistance.

• The Journal of the Convergence on Culture Technology
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• v.7 no.4
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• pp.791-800
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• 2021

British housing types began with detached houses using wood based on early Germanic cultures, and gradually divided into multi-story houses such as terraces houses, with the influx of houses using stone from Latin cultures influenced by France. Today, various types of housing types such as detached houses, townhouses, and apartments are mixed, and their origins can be found in housing types that have continued from the past. Housing types existing in the UK continue their context through this historical development process, but housing types in the UK also have been combined with those of other cultures, leading to modern housing types. In this paper, we examine the process of the UK's peculiar development of housing types superimposed with the recurring motion to the traditional European urban structures prior to the industrial revolution during contemporary years, and perimeter block collective housings of today; then, we study the process of applying the UK case as a concept of practical design and planning in order to continuously consider Korea's modern urban structure and corresponding types of housing. Through this process, we explore the identity of the housing type in Korea, which is pursuing fundamental changes in residential culture beyond quantitative housing supply in the process of rapid urbanization.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.1
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• pp.27-36
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• 2022

Currently the population of rural areas in Korea continue to decline due to low birth rate, aging population, and migration. This phenomenon is accelerated over time. And as a result, there are some declining phenomenon in rural society. And it is same in the residential and basic living conditions of rural villages. The increase ratio of empty houses exacerbates the rural landscape, acts as a cause of crime and bring out various social and economic problems such as worsening settlement conditions and local slums. The study is carried out to prevent this phenomenon by investigating the architectural contents of empty houses in the village, surveyed residents and owners and finally analyzed and synthesized to make a plan to utilize empty houses in the village. This study was conducted from June to December 2021. The conclusions are followings: 1. The empty houses in Korea were 1,511 million in 2020, 8.2% of the total number of houses, whereas those in Jeollabuk-do were 95,412, 12.9% of those of houses, and those in Gimje-city, the subject of this study, were 5,944. It is up to 15.8%. In particular, empty houses in Hacheon village, the site of this study, accounted for the highest ratio, with 25% of the total number of houses. 2. To understand the utilization and improvement of empty houses, surveys and interviews were conducted to residents and owners of Hacheon village in Gimje, and most of the residents submit proposals that empty houses were not desirable in terms of village landscape and safety. The owners don't have intentions of selling or leasing them. They want to remodel them and rent for a specific period. 3. As the physical condition of the empty houses(9empty houses) 6 empty houses of them are good. 4 of them are in poor condition. 4. By synthesizing these contents, nine empty houses in Hacheon village will be remodeled as the space for those of rural start-up young people, smart farm area, community space and rental housings for rural returnees.

• Korean Journal of Construction Engineering and Management
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• v.23 no.5
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• pp.108-116
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• 2022

Started in 1989 as Public Permanent Rental Housing scheme, public rental housing lease policy is increasing target residents and supply in each government by introducing new supply types. However, public housing business entities have difficulties in expanding the supply due to cumulated deficit. The research suggested long-term public rental housing reconstruction business as a method to preserve the cumulated deficit from the previous. Minimum floor area ratio mathematical model was suggested by defining the floor area ratio of reconstruction business as minimum, since housing sales profit after reconstruction could preserve aggregated deficit, and mathematically approached by considering the traits of long-term public rental housing reconstruction. The determinant for minimum floor area ratio mathematical model comprise cumulated deficit of the existing long-term public rental housing, land size of reconstructed sale housing, housing sales price per unit area, and business cost per unit area. Minimum floor area ratio mathematical model is expected to be the milestone for supporting decision making regarding the economic part of old long-term public lease housings' reconstruction scale, and expanding housing supply within urban area.

• Journal of the Korean Wood Science and Technology
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• v.34 no.4
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• pp.37-45
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• 2006

Recently, wood-framed houses has been built in the Korea for pension. Wood is good material for human healthy, while the construction lumbers are treated with preservative such as CCA (chromated copper arsenate), which contain some toxic elements for human body. However, if the waste woody biomass treated with various heavy metals, which has been collected from house construction or demolition, was fired in the field, and incinerated or landfilled after mass collection, such components will result in the toxic air pollutants in the burning or land fills, and spreaded into other areas. So the careful selection of wood and chemicals are required in advance for house construction, in particular, for environment-friendly housings. Therefore, this study was carried out to determine the content of toxic heavy metals in woody materials such as domestic hinoki and imported hemlock treated with CCA for housing materials, and the post-treated wood components such as organic fertilizer, sludge, dry-distilled charcoal and carbonized charcoal, to be returned finally into soil. The results are as follows. 1) The chemical analysis of toxic trace elements in various solid biomass required accurate control and management of laboratory environment, and reagents and water used, because of the error of data due to various foreign substances added in various processing and transporting steps. So a systematic analyzers was necessary to monitor the toxic pollutants of construction materials. 2) In particular, the biomass treated with industrial biological or thermal conditions such as sludge or charcoals was not fully dissolvable after third addition of $HNO_3$ and HF. 3) The natural woody materials such as organic fertilizer, sludge. and charcoals without any treatment of preservatives or heavy metal components were nontoxic in landfill because of the standard of organic fertilizers, even after thermal or biological treatments. 4) The CC A-treated wood for making the construction wood durable should not be landfilled, because of its higher contents of toxic metals than the criterion of organic fertilizer for agriculture or of natural environment. So the demolished waste should be treated separately from municipal wastes.

• Journal of Animal Environmental Science
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• v.16 no.2
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• pp.99-108
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• 2010

The principal objective of this study was to investigate the cooling effects of geothermal heat pump system (GHPS) in farrowing house. A total of 96 sows were allocated to 2 pig housings (GHPS and conventional housing) with 48 for four weeks in summer season. During the experimental period of four weeks, the highest outside temperature observed was approximately $34.1^{\circ}C$, GHPS decrease indoor temperature of pig housing up to $30.9^{\circ}C$, but conventional pig housing was similar to outside temperature. Dust concentrations (maximum 61.4%) of particulate matter less than $10{\mu}m$ (PM 10) in GHPS-housing were lower than the conventional housing. GHPS showed no signigicant difference in carbon dioxide emission, whereas the ammonia gas concentration was significantly decreased in GHPS-housing compared to that of conventional housing. Sows in GHPS-housing showed significantly lower respiratory rate than those of the control group. GHPS did not affect hormone level, litter size and birth weight, but weaning weight of piglets was influenced by GHPS. Feed consumption of sows was significantly increased in GHPS-housing compared to the conventional hosing. These results suggest that GHPS decrease dust concentration, ammonia gas emission and indoor temperature of pig housing and may affect performance in sows and weaned piglets.