• Korean Journal of Heritage: History & Science
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• v.50 no.3
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• pp.88-109
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• 2017

As the technique to remove Paraloid B-72, which is known as an irreversible material, the method using organic solvent and heating, though the ways vary depending on the kind of material to be removed, has been usually used, but it has yet to apply to mud mural because of the technical limit in processing and the potential risk of damage and, moreover, the removal efficiency which also remains unproven. Thus, in a bid to seek the way to safely remove Paraloid B-72 contained in mural, the test was conducted in a way of applying a compress method, which is deemed most efficient. The solvents which are proven to be Paraloid B-72 were applied to the absorbents such as active carbon fiber and methyl cellulose and then were eluted to the surface of mud mural sample which was prepared in the same size and condition for a certain time before evaluating the stability and removal efficiency. Such test was intended to identify the applicability to the mural of Mireukjeon Hall at Geunsansa Temple, which had been treated with Paraloid B-72 for preservation in the past. As a result, the way of mixing the absorbent such as active carbon fiber and Xylene alone or with other quick vaporable solvents proved to be most efficient in removing Paraloid B-72 from mud mural and particularly Acetone:Xylene(1:1wt%) was found to be the most stable among others. Such a test outcome is expected to be a useful data for removing Paraloid B-72 from the mural of Mireukjeon Hall at Geunsansa Temple as well as for restoring other mural cultural assets in the coming days.

• Korean Journal of Environmental Biology
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• v.39 no.3
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• pp.273-288
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• 2021

We analyzed the spatio-temporal distribution characteristics of water quality and phytoplankton communities in the Isa Stream systems (ISS) from Sangsa Lake to Suncheon Bay. Sangsa Lake showed relatively oligotrophic and mesotrophic conditions, but the freshwater and mixed brackish water zones showed more severe eutrophication than Sangsa Lake and Suncheon Bay due to the influence of industrial waste such as livestock waste. In terms of the phytoplankton community, the number of phytoplankton species was higher in freshwater and mixed brackish water zones than in Sangsa Lake and Suncheon Bay, but the cell density and Chlorophyll-a concentrations (Chl-a) were relatively high in Sanga Lake and Suncheon Bay. In particular, the mesotrophic species Fragilaria crotonensis and Asterionella formosa showed different dominance in the surface and bottom layers, and the influence of A. formosa was significant in the freshwater and mixed brackish water zones in spring and summer. However, Skeletonema costatum-ls, a eutrophic indicator species, dominated in mixed brackish water zones to seawater in autumn and winter. Thus, the severe eutrophication and rapid environmental changes in the ISS could seriously damage the coastal ecosystem in Suncheon Bay. These ecosystem changes are threatening in terms of conservation and management of the UNESCO Suncheon Biosphere Reserve and Yeoja Bay including Suncheon Bay, which recorded the first Ramsar wetland in Korea. Therefore, further research is needed to establish an in-depth management plan.

• Korean Journal of Plant Resources
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• v.32 no.4
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• pp.282-289
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• 2019

Gastritis is an inflammatory disease involving the stomach and is caused by several factors, including stress, non-steroidal anti-inflammatory drugs such as aspirin, liquor, and Helicobacter pylori. In Korea, Leonurus japonicus Houttuyn (LJW) has been used as traditional medicine for vaginal bleeding, hematuria, and bruise. Previous studies have reported that LJW exhibited hepatoprotective, cardioprotective, and anti-hyperlipidemic effect. However, the effect of the water extract of LJW on gastritis was not elucidated. Thus, we evaluated the anti-gastric effect and genotoxicity of LJW. LJW effectively prevented the degeneration of surface mucous cells and glandular epithelial cells and vascular congestion induced by HCl/EtOH. Micronucleus assay indicated that the rate of micronucleated polychromatic erythrocytes/polychromatic erythrocytes was not significantly different compared that of the control. Further experiments are required to determine the role of LJW in the gastric injury process such as cyclooxygenase signaling pathway and the secretion of mucus in the stomach.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.38 no.6
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• pp.725-731
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• 2020

In mineral resource development, resource exploration is a task to find economical minerals on the surface and underground, and the success rate is low compared to the development and production stages, and it is necessary to collect a lot of data through exploration and accurately analyze the collected information. In this study, mine spatial information was constructed using a 3D (Three-dimensional) laser scanner, and accuracy evaluation was performed to obtain a maximum deviation of 0.140 m and an average of 0.095 m in the X, Y and Z directions, and the possibility of utilizing the construction of mine geospatial information through a 3D laser scanner could be presented. In addition, the ore body modeling was performed by applying the interpolation method of the ore body section using the resource exploration results. The ore body modeling result was superimposed with the modeling result of the mine geospatial information built through the 3D laser scanner to construct the ore body modeling result based on the precise mine geospatial information. The results of ore body modeling based on mine geospatial information built through research can increase the ease of data interpretation and the accuracy of the calculated data, which will greatly increase the efficiency of work related to mineral resource development and mine damage prevention in the future.

• Journal of Cadastre & Land InformatiX
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• v.50 no.2
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• pp.221-235
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• 2020

The development and utilization of underground spaces are increasing as the use of land based on ground surface became limited due to rapid urbanization triggered by population growth and industrialization. Despite its merit of efficient use of limited land and space, it may contribute to occurrence of various disasters such as sinkholes and damage to underground facilities. After the sinkholes formed and occurred across the country in 2014, there has been an effort to establish Underground Space Integration Map containing 15 types of underground information. Still, there is an increasing demand to improve the quality of underground information stemmed from continuation of such events including the rupture of the hot water pipe in Goyang-si and the fire in the KT site in Ahyeon-dong, Seoul. Hereby, with the aim to improve the quality of Underground Space Integration Map, this study analyzes quality standards, regulations, and guidelines related to spatial data to improve quality inspection standards and methods included in the production rules for the Underground Space Integration Map. In particular, it suggests improvement plan for data quality management for pipe-type underground facilities, known as lifelines, which are essential part of daily life of the citizens, and the largest cause for accidents according to 15 types of underground information managed through the Underground Space Integration Map.

• Korean Journal of Construction Engineering and Management
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• v.22 no.1
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• pp.81-89
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• 2021

In recent years, the design of buildings is changing from formal to creative and freeform. Accordingly, the scale of construction technology is changing to architectural design and construction of irregular buildings. Using the FDM method, which is one of the 3D printing technologies, it is possible to manufacture various forms of irregular formwork inexpensively and quickly coMPared to the existing formwork, and it seems to be able to solve the manpower problem. Using a 3D printer, the PLA filament formwork is produced in the form of a cylinder and a rectangular cuboid, and the usability of the PLA filament formwork is confirmed by examining the compression strength test and the degree of deformation and reusability over 28 days of age. Different sizes of additional specimens are also conducted according to the size. As a result of the experiment, it was confirmed that the filament formwork itself has about 3~4MPa strength. As a result of reviewing data through existing linear studies and experiments, it is appropriate to use more than 60% infill, and it is advantageous in terms of strength. As a result of cutting and dismantling the filament formwork, the surface is very clean and there is no damage, so it can be reused.

• Journal of Platform Technology
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• v.8 no.3
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• pp.10-21
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• 2020

Partial discharge occurs a lot in high-voltage power equipment such as switchgear, transformers, and switch gears. Partial discharge shortens the life of the insulator and causes insulation breakdown, resulting in large-scale damage such as a power outage. There are several types of partial discharge that occur inside the product and the surface. In this paper, we design a predictive model that can predict the pattern and probability of occurrence of partial discharge. In order to analyze the designed model, learning data for each type of partial discharge was collected through the UHF sensor by using a simulator that generates partial discharge. The predictive model designed in this paper was designed based on CNN during deep learning, and the model was verified through learning. To learn about the designed model, 5000 training data were created, and the form of training data was used as input data for the model by pre-processing the 3D raw data input from the UHF sensor as 2D data. As a result of the experiment, it was found that the accuracy of the model designed through learning has an accuracy of 0.9972. It was found that the accuracy of the proposed model was higher in the case of learning by making the data into a two-dimensional image and learning it in the form of a grayscale image.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.4
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• pp.148-159
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• 2021

This study estimates the region of freshwater influence (ROFI) by Han River discharge in the Yeomha channel, Gyeonggi Bay. A 3-D numerical model, which is validated for reproducibility of variation in current velocity and salinity, is applied in Gyeonggi Bay. Distance of freshwater influence (DOFI) is defined as the distance from the entrance of Yeomha channel to the point where surface salinity is 28 psu. Model scenarios were constructed by dividing the Han River discharge into 10 categories (200~10,000 m³/s). The relation equation between freshwater discharge and DOFI was calculated based on performing a non-linear regression analysis. ROFI in Yeomha channel expands from the southern sea area of Ganghwa-do to the northern sea area of Yeongheung-do as the intensity of Han River discharge increases. The discharge and DOFI are a proportional relationship, and the increase rate of DOFI gradually decreases as discharge increases. Based on the relation equation calculated in this study, DOFI in the Yeomha channel can be estimated through the monthly mean Han River discharge. Accordingly, it will be possible to respond and predict problems related to damage to water quality and ecology due to rapid freshwater runoff.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.1
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• pp.77-84
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• 2022

A submarine power cable is a transmission cable for carrying electric power below the surface of the water. Recently, submarine cables transfer power from offshore renewable energy schemes to shore, e.g. wind, wave and tidal systems, and these cables are either buried in the seabed or lie on the ocean floor, depending on their location. Since these power cables are used in the extreme environments, they are made to withstand in harsh conditions and temperatures, and strong currents. However, undersea conditions are severe enough to cause all sorts of damage to offshore cables, these conditions result in cable faults that disrupt power transmission. In this paper, we explore the design criteria for such cables and the procedures and challenges of installation, and cable transfer splicing system. The specification of submarine cable designed with 3 circuits of 154kV which is composed of the existing single circuit and new double circuits, and power capacity of 100MVA per cable line. The determination of new submarine cable burial depth and cable arrangement method with both existing and new cables are studied. We have calculated the permission values of cable power capacity for underground route, the values show the over 100MW per cable line.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.2
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• pp.169-180
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• 2022

Streptococcus sp. is generally known as a strain that produces hyaluronic acid. In this study, we focused on ingredients other than hyaluronic acid among several metabolites produced by Streptococcus sp. during cultivation. The hair experimental sample (HAIRCLE^TM) was prepared with Streptococcus sp. culture filtrate under the condition that hyaluronic acid was not produced and the effect on the hair was identified. Tensile strength of hair was tested with a universal testing machine (UTM). Surface properties of a hair were examined with an atomic force microscope (AFM). Our results suggest that HAIRCLE^TM could prevent damage to a hair such as destroyed-cuticle, increased-faction force, and broken-hair. Furthermore, hair-related experiments confirmed that HAIRCLE^TM could promote the expression of hair growth factors VEGF, HGF, and Wnt10b and mitigate male hair loss by inhibiting androgen receptors and TGF-β2 expression. In addition, it was confirmed that the expression of barrier-related factors (INV, CLDN-1) was increased for oxidative stress, and the COX-2 expression, an inflammatory factor, was inhibited, thereby improving damaged scalp barriers and alleviating induced inflammation.