• Proceedings of KOSOMES biannual meeting
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• 2008.05a
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• pp.185-189
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• 2008

This study was conducted to find out the effects of relationship between ocean conditions and snowfall when cold and dry continental air mass passes through the West Sea of Korea. Route of continental high atmospheric pressure can cause effect on snowfall at the west regions (Inchoen, Gunsan, Mokpo) of the Korean Peninsula. The continental high atmospheric pressure extend from the southern China to western coastal region of the Korean Peninsula during the December, and it extend from the north side of China through Bohai Sea and Yodong Peninsula to central area of the Korean Peninsula during the February. Therefore, more snowfall recorded in Incheon is higher during Feb. than Dec.. whereas Gunsan and Mokpo is the opposite. The heavy snowfall at the western coastal region of Korea was caused by loss of the heat from the ocean to air when it's higher than $100W/m^2$. the heavy snowfall was also observed when the arrangement of continental high atmospheric pressure and low pressure was high at the West and low at the East, which formed a front in West and when the wind blow from the North or North West at the speed of $4\sim8m/sec$. There were not much relation between salinity in the western sea and snowfall in the western coastal region of Korea.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.2941-2951
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• 2018

The purpose of this paper is to analyse the effect of ocean weather factors on shipments of swimming crab. We use the data of data portal and ocean weather factors (mean wind velocity, mean atmospheric pressure, mean relative humidity, mean air temperature, mean water temperature, mean maximum wave height, mean significant wave height, maximum significant wave height, maximum wave height, mean wave period, maximum wave period). We did statistical analysis using Poisson regression analysis and negative binomial regression analysis. As the result of study, important factors influential in the shipments of swimming crab turn out to be mean wind velocity, mean atmospheric pressure, mean relative humidity, mean water temperature, maximum wave height, mean wave period and maximum wave period. the shipments of swimming crab increases as mean wind velocity, mean atmospheric pressure, mean relative humidity, mean water temperature increases or mean wave period increase. However, as maximum wave height, maximum wave period decreases, the shipment of swimming crab increases.

• Journal of Dental Rehabilitation and Applied Science
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• v.37 no.2
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• pp.88-94
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• 2021

Purpose: The purpose of this study was to evaluate the anti-inflammatory effects of non-thermal atmospheric pressure plasma (NTP) on human gingival fibroblasts (HGFs) for clinical application of periodontal treatment. Materials and Methods: HGFs were treated with Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS). Customized NTP device was developed for periodontal in vitro study. Cell viability was evaluated with cell counting kit-8. The levels of inflammatory cytokines, including interleukin (IL)-8 and 6, were determined by enzyme-linked immunosorbent assay. Results: When NTP was applied, the cell viability did not change significantly, and there was no difference for 6 h and 24h. When Pg LPS was treated to HGFs, the secretion of IL-8 and IL-6 was increased compared to the control group. But when the NTP was applied, the secretion of them was significantly decreased. Conclusion: NTP did not affect cell viability of HGFs. And it inhibited the LPS-induced production of IL-8 and IL-6.

• Korean Journal of Remote Sensing
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• v.36 no.6_3
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• pp.1635-1641
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• 2020

Air pollution is one of the most severe threats to society globally due to the rapid expansion of urbanization and industrialization. Particularly, particulate matter (PM) pollution was recently designated as a social disaster by the Korean government because of increases in public concerns and the accumulation of scientific evidence that links high levels of PM2.5 (PM smaller than 2.5 ㎛ in diameter) to a long list of adverse health effects. Atmospheric PM concentrations can also affect the indoor PM levels to which people are exposed most of the time. Thus, understanding the characteristics of indoor and ambient PM pollution based on measurements, model simulations, risk assessments, and management technologies is inevitable in establishing effective policies to mitigate social, economic, and health costs incurred by PM pollution. In this special issue, we introduce several interesting studies concerning indoor and outdoor PM from the perspective of monitoring, assessment, and management being conducted by i-SEED (School of Integrated Science for Sustainable Earth & Environmental Disaster at Pukyong National University) and SPMC (School Particulate Matter Center for Energy and Environmental Harmonization). We expect that this special issue can improve our understanding of the current and future of indoor and outdoor PM pollution, integrating the results from interdisciplinary research groups from various academic fields.

• Korean Journal of Remote Sensing
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• v.38 no.5_3
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• pp.851-861
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• 2022

In this study, we analyzed the effects of trees planted in urban areas on PM_2.5 reduction using a computational fluid dynamics (CFD) model. For realistic numerical simulations, the meteorological components(e.g., wind velocity components and air temperatures) predicted by the local data assimilation and prediction system (LDAPS), an operational model of the Korea Meteorological Administration, were used as the initial and boundary conditions of the CFD model. The CFD model was validated against, the PM_2.5 concentrations measured by the sensor networks. To investigate the effects of trees on the PM_2.5 reduction, we conducted the numerical simulations for three configurations of the buildings and trees: i) no tree (NT), ii) trees with only drag effect (TD), and iii) trees with the drag and dry-deposition effects (DD). The results showed that the trees in the target area significantly reduced the PM_2.5 concentrations via the dry-deposition process. The PM_2.5 concentration averaged over the domain in DD was reduced by 5.7 ㎍ m^-3 compared to that in TD.

• Korean Journal of Environment and Ecology
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• v.36 no.4
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• pp.402-412
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• 2022

This study investigated each forest's stand characteristics and the NVOCs emission characteristics for Quercus acuta, Castanopsis sieboldii, Dendropanax trifidus, Camellia Japonica which are major warm temperate evergreen broad-leaved species, and Pinus thunbergii. Data were collected from May 2019 to January 2020. The seasonal temperature and humidity of each research site indicated the typical climatic characteristics of Korea, which are hot and humid in summer and cold and dry in winter. Also, the atmospheric pressure was generally high in winter and higher in autumn and winter than in spring and summer. Overall, the total volume of NVOCs (Natural Volatile Organic Compounds) from the five research sites was the highest in the summer. The concentration of TNVOCs was relatively high in the Dendropanax trifidus forest in spring and winter, the Castanopsis sieboldii forest in the autumn, and the Quercus acuta forest in the summer. According to the results of this study, it was confirmed that the concentrations of NVOCs emission of warm temperate evergreen broad-leaved species such as Quercus acuta, Castanopsis sieboldii, Dendropanax trifidus and Camellia Japonica were not lower but rather higher than Pinus thunbergii. The correlation was positive (+) between NVOCs emission and temperature (r=0.590, P=0.000) or humidity (r=0.655, P=0.000), whereas it was negative (-) between NVOCs emission and atmospheric pressure (r=-0.384, P=0.000) or wind speed (r=-0.263, P=0.018). Among the micrometeological factors, humidity (β=0.507, P=0.000) was found to have the greatest effect on NVOC emission, followed by temperature, atmospheric pressure, and wind speed.

• Journal of the Korean Society of Food Culture
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• v.24 no.1
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• pp.69-76
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• 2009

This study was conducted to determine the optimal cooking conditions for brown rice using an electric pressure rice cooker. The effects of steeping conditions and cooking pressure on the hydration, gelatinization, texture and palatable properties of cooked brown rice were evaluated. Based on water uptake and DSC data, the optimal steeping time and temperature for brown rice were determined to be 25 minutes and ${\sim}60^{\circ}C$, respectively. The cooking conditions for brown rice were then divided into the following 6 categories: steeping at $25^{\circ}C$ for 25 minutes and cooking at an atmospheric pressure of 1.7 (25P) or 1.9 (25HP), steeping at $57^{\circ}C$ for 25 minutes and cooking at an atmospheric pressure of 1.7 (57P) or 1.9 (57HP), steeping at $85^{\circ}C$ for 15 minutes and cooking at an atmospheric pressure of 1.7 (85P) or 1.9 (85HP). The susceptibility of cooked brown rice starch to degradation into maltose by ${\alpha}$-amylase, which is related to the degree of gelatinization and in vitro digestibility, were then determined. The amount of maltose produced by cooked brown rice samples was highest in the 57HP group, followed by the 57P and 85HP groups. Storing cooked brown rice at $73^{\circ}C$ for 24 hours resulted in significantly higher amounts of starch being degraded into maltose in the 57P, 57HP and 85HP groups than in the other groups. Textural analysis demonstrated that the 57P, 57HP and 85HP groups had significantly lower gumminess and chewiness values when compared to the other groups, and that 57HP received had the lowest hardness of all treatments. These results were confirmed by the results of the sensory evaluations. Furthermore, the 57P and 57HP groups were found to have a higher glossiness, stickiness aroma and taste score than the other groups. These findings were taken to indicate that steeping conditions and pressure exerted a positive synergistic effect on the cooking quality of brown rice. The texture analyzer also revealed that storing the cooked rice at $73^{\circ}C$ for 24 hours only led to significantly lower scores in gumminess, hardness and chewiness in the 57P and 57HP groups, which indicates that these groups underwent a lesser degree of retrogradation than other groups. Taken together, the results of the present study demonstrate that steeping brown rice at $57^{\circ}C$ for 25 minutes and a higher cooking pressure improved the palatability and in vitro digestibility of brown rice significantly.

• Corrosion Science and Technology
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• v.17 no.5
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• pp.203-210
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• 2018

This paper compares the inhibition properties of aspartic and lactic acid salts with nitrite ions and their effect on critical chloride concentration. The tests were carried employing carbon steel specimens in saturated lime solution with varying pH in the range between13 to 13.6. The critical chloride concentration was estimated through multiple specimen potentiostatic tests at potentials in the usual range for passive rebar in the alkaline concrete of atmospheric structures. During tests, chloride salt was added every 48 h until all the specimens showed localized attacks. The cumulative distribution curves, i.e. the number of corroded specimens as a function of the chlorides concentration was obtained. Furthermore, IR spectra were recorded for the evaluation of the presence of the organic inhibitors on the passivity film. The results confirmed the inhibitory effect of 0.1M aspartate comparable with nitrite ions, at a similar concentration. Addition of calcium lactate did not result in an increase in the critical chloride concentration. However, the formation of a massive scale containing the substance that could reduce the corrosion propagation was observed.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.491-494
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• 2008

The hydrogen fuel and fuel cell which have high energy efficiency and low pollutant emission are getting interest as an alternative energies due to the fossil fuel exhaust, green house effect and atmospheric pollutant problems. The hydrogen gas is very effective as an alternative energy. But, if it is leaked into the air it forms the mixed gas with the air then the danger of the explosion is risen up. So, the secure the safety is mostly important. In this research, to detect the leakage of the hydrogen rapidly, added the odorant materials which don't include the sulfur component into the hydrogen gas and researched on the effect of each odorant on the performance of the fuel cell. As the results, setting the cumulation electric power on the basis and comparing the pure hydrogen, 2,3-Butanedione 5ppm mixed gas 86.1%, 5-Ethylidene-2-Norbornene 17ppm mixed gas 88.2%, Isovaleraldehyde 10ppm mixed gas 74.8%, Ethyl Isobutyrate 2.2ppm mixed gas 93.5% of performance was shown.

• Journal of electromagnetic engineering and science
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• v.18 no.1
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• pp.52-57
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• 2018

Surface dielectric barrier discharge (SDBD), which is widely used to control turbulence in aerodynamics, has a significant effect on the radar cross-section (RCS). A four-way linearly synthesized SDBD air plasma actuator is designed to bolster the plasma effects on electromagnetic waves. The diffraction angle is calculated to predict the RCS because of the periodic structure of staggered electrodes. The simplified plasma modeling is utilized to calculate the inhomogeneous surface plasma distribution. Monostatic RCS shows the diffraction in the plane perpendicular to the electrode array and the notable distortion by plasma. In comparison, the overall pattern is maintained in the parallel plane with minor plasma effects. The trends also appear in the bistatic RCS, which has a significant difference in the observation plane perpendicular to the electrodes. The peaks by Bragg's diffraction are shown, and the RCS is reduced by 10 dB in a certain range by the plasma effect. The diffraction caused by the actuator and the inhomogeneous air plasma should be considered in designing an SDBD actuator for a wide range of application.