• Journal of Wetlands Research
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• v.16 no.4
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• pp.443-452
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• 2014

Feces contain nutrients such as nitrogen and phosphate, potassium and research of the impact on the environment from feces is very diverse. However, despite the importance of mammals to environment, studies of mammals into the terrestrial ecosystems are rare. Korean water deer (Hydropotes inermis) is an endemic species of Korea and China, and we conducted on factor of plant growth in relation to feces of Korean water deer depending on land use patterns. The analysis of growth, biomass and C/N ratio of Zea mays, amount of feces and land use patterns are strongly affecting the C/N ratio and growth of the Zea mays. The quantity of the feces also influences the growth of plants instead of the land use patterns. Furthermore, the feces of Korean water deer have a lower C/N ratio than that of other animals' feces. Being the process of composting, it is able to serve a suitable fertilizer for a crop growth. In this study, we investigated the impact of feces into the environment in the terrestrial ecosystems and we were able to provide the basic data to the resources of an efficient scheme of animal feces. Further research is needed to quantify the materials amongst the plant, soil and animal, and to understand the relationship ecosystem.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.5
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• pp.787-799
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• 2017

Although the long-term leakage between the box culvert and the soil contact surface is one of the main causes of the failure in the embankment of the reservoir, there is a little studies on this matter. If a leakage occurs by the structure such as the buried box culvert of reservoir embankment is partially damaged, it is difficult to observe and there is a possibility of damage caused by piping. For these reasons, more research is necessary. In this study, the embankment type of the reservoir is divided into the core type and the homogeneous type when the damaged box culvert passing through the embankment of the reservoir is leaked due to the differential behavior of materials like differential settlement. In view of the condition, the seepage analysis of 2D was performed according to the water level change. The result of the study shows that the possibility of piping increases at the upper part rather than the bottom part of the box culvert when the leakage occurs to the box culvert passing through the embankment of the reservoir. Particularly, it is considered that the presence of the core helps to maintain the seepage stability of the embankment in case where the leakage occurs at the downstream side of the embankment. Also, if there is a drastic decrease on the internal pore water pressure in the embankment of reservoir, it is necessary to consider the possibility of piping.

• Journal of Conservation Science
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• v.25 no.3
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• pp.299-316
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• 2009

The Goryeo roof tiles from the Oegol site in Tangjeong, Asan are classified into three groups in color such as gray, red yellow and gray-yellow groups, respectively. While each group of tiles shows characteristic specific gravity, absorption ratio, LOI and vitrification degree, mineral content and distribution, and chemical composition are generally homogeneous among all groups of roof tiles. Also, all roof tiles and soils from the site show similar geochemical behavior of elements and clay-mineralization degree. This indicates that the soil from the site is probable to be a raw material of the roof tiles. Firing temperature of the roof tiles is estimated as 950 to $1,050^{\circ}C$ for the gray group, 800 to $900^{\circ}C$ for the red yellow group, and 900 to $950^{\circ}C$ for the gray-yellow group. In conclusion, roof tiles from the Oegol site is interpreted to be made of local clay without additive minerals, applying various firing conditions and standardized purifying process of raw clay materials.

• Journal of Conservation Science
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• v.25 no.3
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• pp.273-282
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• 2009

As a result of investigating research papers concerning the metal bound rim decoration on four pieces of 'Bowl, white porcelain with impressed floral design and sliver bound rim' and one piece of 'Bowl, white porcelain with sliver bound rim' from among the Jingdezhen white porcelain, which are Sinan remains that are kept in a National museum of Korea. It was found that the material of the bound rim was not silver but tin, and lacquer was used as glue. Based on such a scientific analysis, this study conducted a reproduction test of the manufacturing technique and the bonding method of the metal bound rim attached to the upper tip of the china ware. As a way of reproducing the bound rim, the study was able to discover the best method in terms of the avoidance of loss of materials and the workability out of various cutting methods for tin plates, and it also discovered that the use of lacquer in mixture with soil showed a better workability than the use only of a lacquer ingredient in a test of the bonding method of a metal bound rim using lacquer. Also, in the test of a drying method, a bonding method after drying within a short time at a relatively high temperature was found to be more effective than the drying method after humidifying at a normal temperature, which is used in traditional lacquer ware preservation treatment.

• Korean Journal of Environmental Agriculture
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• v.36 no.1
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• pp.22-28
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• 2017

BACKGROUND: There is very limited knowledge of the effects of biochar derived from exhausted coffee residue on metal adsorption processes. Furthermore, only limited information is available on the adsorption mechanism of copper. The aim of this study was to evaluate the absorption behaviors of copper by biochar derived from exhausted coffee residue. METHODS AND RESULTS: Biochars produced by pyrolysis of exhausted coffee residue at $300^{\circ}C$(CB300) and $600^{\circ}C$(CB600) were characterized and investigated as adsorbents for the removal of copper from aqueous solution. The results indicated that the adsorption equilibrium was achieved around 2 h and the pseudo-second-order kinetic model fit the data better than the pseudo-first-order kinetic model. The maximum Cu adsorption capacities of CB600 by Freundlich and Langmuir isotherms were higher than those of CB300. The adsorption data were well described by a Langmuir isotherm compare to Freundlich isotherm. CONCLUSION: Our results suggest that exhausted coffee residue can be used as feedstock materials to produce high quality biochar, which could be used as adsorbents to removal copper.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5369-5377
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• 2014

Korean pagodas were constructed in the shape of a wood pagoda, brick pagoda, stone pagoda, etc. On the other hand, the currently remaining traditional pagodas are those having nonflammable materials, such as brick, stone, etc. Compared to the stone pagoda, there is data regarding brick pagodas, but there is little literature data on how to construct these pagodas. This appears to be because there are relatively few Korean brick pagodas currently remaining, they are locally restricted, the material limit is not overcome, pagoda's historical and regional problems have not been analyzed, and pagoda construction is centered on pagoda construction. Therefore, this study examined the local cultural characteristics on the construction of brick pagodas. As a result, cultural exchange between Korea and China was performed through the silk road and there was a marine route for cultural exchange. Such exchange was shared with the East Asia area as well, which can be found by comparing remains at related areas. Exchange with China can be mentioned as the selective exchange of local powers as well as blind learning. Second, brick pagoda were constructed in Korea because of the good quality soil easily. Uisang's Hwaeomjong was negotiated with the main power not agreeing with Buddhism, which was popularized and the local power. Third, brick pagoda construction was influenced by negotiation related between Balhae and Silla, in which the ethnic influence was locally affected and could be mentioned as being a culturally selective result transferred from China. As a result, brick pagodas can be oriented by forming a unitary state rather than a small country within China's influence range as well as cultural transfer through the silk road.

• Journal of the Korean Geotechnical Society
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• v.27 no.12
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• pp.17-25
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• 2011

A fabric of soil media may change due to certain factors such as dissolution of soluble particles, desiccation, and cementation. The fabric changes affect the mechanical behavior of soils. The purpose of this study is to investigate the effects of geo-material dissolution on shear strength. Experiments and numerical simulations are carried out by using a conventional direct shear and the discrete element method. The dissolution specimens are prepared with different volumetric salt fraction in sand soils. The dissolution of the specimens is implemented by saturating the salt-sand mixtures at different confining stresses in the experimental study or reducing the sizes of soluble particles in the numerical simulations. Experimental results show that the angle of shearing resistance decreases with the increase in the soluble particle content and the shearing behavior changes from dilative to contractive behavior. The numerical simulations exhibit that macro-behavior matches well with the experimental results. From the microscopic point of view, the particle dissolution produces a new fabric with the increase of local void, the reduction of contact number, the increase of shear contact forces, and the anisotropy of contact force chains compared with the initial fabric. The shearing behavior of the mixture after the particle dissolution is attributed to the above micro-behavior changes. This study demonstrates that the reduction of shearing resistance of geo-material dissolution should be considered during the design and construction of the foundation and earth-structures.

• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.80-87
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• 2001

This study was conducted to provide basic data for the design of shading facility of greenhouse. The proper distance between external shading screen and roof surface, transmissivity of shading materials, and shading effects of external and internal shadings were analyzed. About a distance of 10 cm between inclined external shading screen and roof surface was enough to guarantee the external shading effect in the greenhouse without roof vent. The inside temperature of greenhouse installed with 85% internal shading screen was lower the maximum of 4$^{\circ}C$ and mean of 2$^{\circ}C$ than that with 55% internal shading screen in both natural ventilation and no ventilation condition. The difference of soil temperature between shading and no shading greenhouse was great, but the difference by shading rate or shading method was small. The performance of external shading for controlling inside temperature down was superior to that of the internal shading. The externally inclined shading screen parallel to the roof surface of greenhouse was more effective than the externally horizontal shading screen in controlling inside temperature of greenhouse without roof vent.

• The Journal of Engineering Geology
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• v.17 no.3
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• pp.359-365
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• 2007

Freezing and thawing cycle is one of the major weathering-induced factors in the mechanical weathering of the rock mass. This natural process accelerates rock weathering process by breaking down the parent rock materials and makes soil or weathered rock formation in a rock slope surface zone. It can also cause reduction of the shear strength in slopes. It is important to calculate the deterioration depth caused by freezing-thawing for a slope stability analysis. In this study, deterioration depths of rock slope due to freezing-thawing were calculated using the 1-D heat conductivity equation. The temperature distribution analysis was also carried out using collected temperature distribution data for last five years of several major cities in Korea. The analysis was performed based on the distributed rock types in study areas. Thermal conductivities, specific heats and densities of the calculation rocks are tested in the laboratory. They are thermal properties of rocks as input parameters for calculating deterioration depths. Finally, the paper is showing the calculated deterioration depths of each rock type slopes in several major cities of Korea.

• Journal of Environmental Impact Assessment
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• v.27 no.3
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• pp.241-250
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• 2018

Recently, negative effects on human health such as disease caused by harmful environment have been dealt with seriously. In particular, studies on the effect of radon exposure, which is known as a primary carcinogen in lung cancer due to radioactive materials, have been actively studied. In Korea, since January 1, 2018, radon measurement is mandatory when building a new apartment, so it is necessary to measure the radon concentration and submit it to the local government and it should be posted where residents can see it. Radon has only recommended standards for multi-use facilities, but now it has decided to set recommendation standards for private homes. Therefore, it should now be possible to manage the radon in the environmental impact assessment phase as well as in the Post-environmental Impact Assessment. It should be possible to share health information such as the radon concentration and the risk of radon, and participation of health experts in the environmental impact assessment stage is required. Soil, air quality, hygiene and aerial items should be improved to take into account the effects of radon on human health during the environmental impact assessment process. If the level value of conncentration of radon shows above the recommended level, then alternative measures should be prepared and mitigation measures should be prepared as well.