• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.926-932
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• 2017

Image distortion can occur when photographing deep sea targets with an optical camera. This problem arises because sunlight is not sufficiently transmitted due to seawater and various floating particles of dust. Particularly, color distortion takes place, causing green and blue color channels to be over emphasized due to water depth, while distortion of boundaries also occurs due to light refraction by seawater and floating particles of dust. These distortions degrade the overall quality of underwater images. In this paper, we analyze underwater images of the bottom of vessels. Based on the results, we propose a technique for color correction and edge enhancement. Experimental results show that the proposed method increases edge clarity by 3.39 % compared to the effective edges of the original underwater image. In addition, a quantitative evaluation and subjective image quality evaluation were concurrently performed. As a result, it was confirmed that object boundaries became clear with color correction. The color correction and contour enhancement method proposed in this paper can be applied in various fields requiring underwater imaging in the future.

• Journal of The Korean Society of Agricultural Engineers
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• v.61 no.4
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• pp.11-22
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• 2019

The objective of this study was to improve the cross-sectional area and height estimation method using stream width. Stream water levels should be calculated together to simulate inundation of agricultural land. However, cross-sectional survey data of small rural rivers are insufficient. The previous study has developed regression equations between the width and the cross-sectional area and between the width and the height of stream cross-section, but can not be applied to a wide range of stream widths. In this study, cross-sectional survey data of 6 streams (Doowol, Chungmi, Jiseok, Gam, Wonpyeong, and Bokha stream) were collected and divided into upstream, midstream and downstream considering the locations of cross-sections. The regression equations were estimated using the complete data. $R^2$ between the stream width and cross-sectional area was 0.96, and $R^2$ between width and height was 0.81. The regression equations were also estimated using divided data for upstream, midstream and downstream considering the locations of cross-sections. The range of $R^2$ between the stream width and cross-sectional area was 0.86 - 0.91, and the range of $R^2$ between width and height was 0.79 ? 0.92. As a result of estimating the cross-sections of 6 rivers using the regression equations, the regression equations considering the locations of cross-sections showed better performance both in the cross-sectional area and height estimation than the regression equations estimated using the complete data. Hydrologic Engineering Center - River Analysis System (HEC-RAS) was used to simulate the flood stage analysis of the estimated and the measured cross-sections for 50-year, 100-year, and 200-year frequency floods. As a result of flood stage analysis, the regression equations considering the locations of cross-sections also showed better performance than the regression equations estimated using the complete data. Future research would be needed to consider the factors affecting the cross-sectional shape such as river slope and average flow velocity. This study can be useful for inundation simulation of agricultural land adjacent to an unmeasured stream.

• Journal of Food Hygiene and Safety
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• v.34 no.2
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• pp.178-182
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• 2019

This study investigated the antibacterial effects of BioZone atmospheric plasma (AP) against Bacillus cereus (F4810/72) and Staphylococcus aureus (ATCC 6538) as the major foodborne bacteria on the surface of dried filefish (Stephanolepis cirrhifer) fillets. The fillets were experimentally contaminated with 7-8 log CFU/mL of B. cereus or S. aureus using a spot inoculation method. Bacterial counts were measured by standard plate method on tryptic soy agar, and were significantly reduced with the increase in the treatment time (1, 3, 5 or 20 min) of AP on the fillets (p < 0.05). The reductions of the pathogens by AP treatment ranged from 0.9 to 2.93 logCFU/g for B. cereus and from 1.04 to 2.55 logCFU/g for S. aureus. A reduction of >1-logCFU/g for B. cereus and S. aureus was observed on the fillets treated with AP for >3 min. The differences in color on the Hunter scale (L=light vs. dark, a=red vs. green, b=yellow vs. blue) of the fillets were not significantly different between the nontreated (control) and AP-treated fillets (p>0.05). This study suggested that 3 min of AP could be effective in reducing >90% of the bacteria without causing any concomitant changes in the color of the fillets.

• Applied Chemistry for Engineering
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• v.34 no.1
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• pp.36-44
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• 2023

Core-shell TiO₂/Ag nanoparticles were synthesized by a modified sol-gel process and the reverse micelle method using acetoxime as a reducing agent in water/dodecylbenzenesulfonic acid (DDBA)/cyclohexane. The structure, shape, and size of the TiO₂/Ag nanoparticles were investigated using X-ray diffraction (XRD), UV-visible spectroscopy, scanning electron microscope (SEM), transmission electron microscope (TEM), and thermogravimetric analysis (TGA). The size of TiO₂/Ag nanoparticles could be controlled by changing the [water]/[DDBA] molar ratio values. The size and the polydispersity of TiO₂/Ag nanoparticles increased when the [water]/[DDBA] molar ratio rose. The resultant Ag nanoparticles over the anatase crystal TiO₂ nanoparticles exhibited a strong surface plasmon resonance (SPR) peak at about 430 nm. The SPR peak shifted to the red side with the increase in nanoparticle size. Conductive pastes with 70 wt% TiO₂/Ag nanoparticles were prepared, and the pastes were coated on the PET films using a screen-printing method. The printed paste films of the TiO₂/Ag nanoparticles demonstrated greater surface resistance than conventional Ag paste in the range of 405~630 μΩ/sq.

• Resources Recycling
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• v.31 no.1
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• pp.37-45
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• 2022

The development of the electrical, electronic, and telecommunication industries has increased the share of electricity in total energy consumption. With the enforcement of the Act on the Promotion of the Development, Use, and Diffusion of New and Renewable Energy in 2021, the mandatory supply ratio of new and renewable energy is expected to expand, and the amount of waste cables generated in the stage of replacing and discarding cables used in the industry is also expected to increase. The purpose of this study was to quantify the environmental burden of waste cable recycling through the life cycle assessment (LCA) method. The results showed that the higher the amount of glue contained in the waste cable, the greater was the amount of fine dust and greenhouse gases generated. In addition, by assigning weights to 10 environmental burden items, it was confirmed that the marine aquatic eco-toxicity potential (MAETP) and human toxicity potential (HTP) had the greatest environmental burden. The main causes were identified as heptane and ethanol, which were the glue contained in the waste cable and the cleaning solutions used to remove them. Therefore, it is necessary to refrain from using glue in the cable production process and reduce the environmental burden by reducing the use of waste cable cleaning solutions used in the recycling process or using alternative materials.

• Journal of Environmental Impact Assessment
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• v.31 no.1
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• pp.63-74
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• 2022

In orderto understand the urban thermal conditions, many studies have been conducted to estimate the thermal fluxes. Currently sensible heat fluxes are estimated through various methods, but studies about comparing the differences between each method are very insufficient. Therefore, this study try to estimate the sensible heat flux of the same area by two representative estimation methods and compare their results to confirm the significance and limitation between methods. As a result of the study, the heat balance methods has a great advantage in terms of resolution but it can not consider the anthropogenic heat flux, so sensible heat flux can be underestimated in urban areas. When estimating based on physical equation, anthropogenic heat flux can be considered and the error is relatively small, it has a limitations in time and space resolutons. The two methods showed the largest difference in industiral areas where anthropogenic heat fluxes are high, with an average of 135 W/m² and a maximum of 400 W/m². On the other hand, the green and water have a very small difference with and average of 20 W/m². The results between two methods show significant differences in urban areas, it is necessary to select a suitable method for each research purpose.

• Journal of the Korean Geotechnical Society
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• v.39 no.2
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• pp.31-42
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• 2023

A study was conducted to use soil color obtained from digital im ages as an indicator of soil water content. Digital images of Jumoonjin standard sand with five different water contents were captured under nine different lighting conditions. Through digital image processing, the soil color of the sample was obtained based on the CIELAB color system, and the effect of lighting conditions and water content on the soil color was analyzed. The results indicated that L^* showed a high correlation with illuminance, whereas a^* and b^* showed a high correlation with color temperature. As the water content increased, L^*, which represents the brightness of the soil color, decreased, and a^* and b^* increased. Therefore, the soil color changed from green and blue to red and yellow. Based on the regression analysis results of lighting conditions, water content, and soil color, a water content predicting method based on the soil color of silica-based sand photographed under irregular light conditions was proposed. The proposed method can predict the water content with a m axim um error of 0.29%.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.1
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• pp.85-97
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• 2023

Seoul Boramae Park was opened on May 5, 1986, after the Republic of Korea Air Force Academy relocated to Cheongju City in 1985. This study aims to examine the birth and evolution of Seoul Boramae Park and diagnose the park's value being transformed from the former site of the Air Force Academy. Policy reports and newspaper data were analyzed as a research method, focusing on Seoul public records. The study results are as follows. First, Seoul Boramae Park is a large-scale park created before the policy for parks on relocated sites we enacted. Second, Seoul Boramae Park has historical value as an urban park where memories and traces of the Air Force Academy overlap. Third, Seou Boramae Park contributed to regional change by promoting the public value of parks created on the relocated sites with an urban planning method. Seoul Boramae Park has implications for Korean landscape history as a case of securing large green areas in Seoul and presenting its function and roles as a park created on a relocated site.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.9-15
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• 1986

To establish an efficient light control method using three covering materials on tunnel shaped rice seed-bed at greening stage after seedling emergence, four rice cultivars, Nampungbyeo, Taebaegbyeo, Seonambyeo, and Seomjinbyeo were sown on 15 April and 10 May in 1983 and 1984 respectively. After seedling emergence by a simplified emerging methods the seedling boxes were moved onto tunnel shaped seed-bed which was covered with combined matrials of PE film, silverpoly sheet, and spunbonded polyester fabric. For machine transplanting of rice seedlings in cases of early season and optimum season seeding in central part of Korea, PE film tunnel with silverpoly mulched, and PE film tunnel methods with spunbonded polyester fabric mulched reduced injuries of non-parasitic seedling damping-off and a albinism as affected by it, protected rice seedlings from injuries by extremely low temperature in the night, and reduced less differences in diurnal temperature than those in the other covering methods. At late season seeding for double cropping system of paddy field in southern part of Korea, a single silver-poly or a single spunbonded polyester fabric-covered tunnel method showed good green seedlings, and prevent-ed extreme rising of diurnal temperature by light interception in the tunnel.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.3
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• pp.61-74
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• 2013

This study examined and analyzed ancient writing and poetry regarding cases of appreciating plants by using pots in a garden of a palace or private houses by ancestors, and examined shape and planting method of plant species and potted plants, arrangement and preference of potted plants. As for the method of the study, description research method which examines and interprets poem and painting based on potted plants. The results of this study is summarized like the following. First, the plants which were favorably used for potted plants include 19 kinds such as Prunus mume, Pinus densiflora, Pinus pumila, Phyllostachys spp., Camellia japonica, Punica granatum, and Gardenia jasminoidesa, and as for herbs, 12 kinds such as Chrysanthemum monifolium and Nelumbo nusifera . Second, the species which were specially arranged into artificial shapes include Prunus mume and Pinus densiflora. The two plants made the shape of severe curves of stems such as Wangpi. Gyuban, and Bangan, and there are Pinus densiflora dwarfed potted plant whose roots are stretched on Prunus mume grafted into a strange stump and an oddly shaped stone. For the beauty of the dwarfed tree shape, pine cones are added to an old Pinus densiflora or Parthenocissus tricuspidata is planted to stems, and additional method of making moss on the soil, which is called 'Jongbunchuigyeong'. As for planting method, water culture, planting on a stone, planting on a charcoal, and assembled planting are expressed in poetry. Third, as for external space for potted plants, a place where a king stays, a bed room for a king, surrounding areas and gardens of private houses, and step stones were used as a space which adds artistic effects. Potted plants are placed on a table in a library, on a desk, on a drawer, and near a pillow as a small items in a room, and scholars enjoyed original characteristics and symbolism of the potted plants. Fourth, at the time of flowering of Prunus mume, poetry event was held to enjoy the tree and writing poetry begun. And at the time of flowering of Chrysanthemum monifolium, the flowers were floated in a liquor glass or shadow play was enjoyed. Fifth, potted plants played the role of garden ornaments in elegant events of a palace, the gentry, wedding ceremony, and sacrificial rites. Sixth, potted plants were used as tributes between countries, donation to a king, or a gift of a king. In addition, there were many cases where scholars exchanged potted plants and there is the first record of giving a potted plant in 'Mokeunsigo' by Mokeun Isaek, scholar in the late era of Goryeo. Seventh, at the time of flowering Prunus mume, Chrysanthemum monifolium, Gardenia jasminoides, Nelumbo nusifera, and Narcissustazetta var. chinensis, they enjoyed the particular fragrance and express it into poetry. Eighth, plant species from southern parts such as Camellia japonica, Daphne odora, Gardenia jasminoides, Citrus unshiu, Phyllostachys spp., Punica granatum, Rosa rugosa, and Musa basjoo, or foreign plant species, and species weak against the cold were utilized as pot plants for enjoying green trees indoors in northern central province in harshly cold winter.