• Journal of Conservation Science
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• v.33 no.4
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• pp.267-274
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• 2017

The Silleuksa temple in Yeoju city is adjacent to the South Han River and often has high humidity and fog days. In addition, its proximity to forests renders it prone to damage by insects and microorganisms. In order to obtain the basic data necessary for the establishment of a cultural property preservation management plan, the biological distribution of the wooden buildings and the termite distribution in the surrounding forests were monitored for three years. The wood-boring bee, an insect known to inflict damage to heritage structures, was confirmed, and the distribution of insects varied annually and seasonally, presumably due to the location characteristics of the site and the climate change during the year. In the forest behind, termite colonies were identified as a whole and their distribution pattern was different every year. As per the results of the microorganism survey, the species distribution and pollution degree were different at the entrance of the building. Therefore, it needs continuous biological distribution and conservation environment monitoring to mitigate the effects of wood-damaging organisms.were different according to the entrance of the building.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.3
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• pp.75-82
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• 2016

Objective of this experiment was to predict the potential methane production with crop residues at different loading rates. Anaerobic digestion of barley and rapeseed straw substrates for biogas production was performed in Duran bottles at various biomass loading rates with crop residues. Through kinetic model of surface methodology, the methane production was fitted to a Gompertz equation. For the biogas production at mesophilic digestion with crop residues, it was observed that maximum yield was 37.2 and 28.0 mL/g at 6.8 and 7.5 days after digestion with 1% biomass loading rates of barley and rapeseed straws, respectively. For the methane content of mesophilic digestion, there were highest at 61.7% after 5.5 days and 75.0% after 3.4 days of digestion with barley and rapeseed straw on both 5% biomass loading rates, respectively. The maximum methane production potentials were 159.59 mL/g for 1% barley straw and 156.62 mL/g for 3% rapeseed straw at mesophilic digestion. Overall, it would be strongly recommended that biomass loading rate was an optimum rate at mesophilic digestion for using 1% barley and 3% rapeseed straws for feed stocks.

• Fire Science and Engineering
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• v.27 no.3
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• pp.1-7
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• 2013

The wildland fire intensity and scale are getting bigger owing to climate change in the world. In the case of domestic, the forest is distributed over approximately 63.7 % of country and the main facilities like a industrial facility or gas facility abuts onto it. Therefore there is potential that the wildland fire is developed to a large-scale disaster. In this study, the effect distances of the radiant heat flux from the crown fire are analysed according to the change of wind velocity. The safety criteria concerning the radiant heat flux to influence on the surrounding were researched to analyse the effect distances. The criteria of radiant heat flux were chosen $5kW/m^2$, $12.5kW/m^2$, $37.5kW/m^2$. WFDS, which is an extension of NIST's Fire Dynamics Simulator, was used to consequence analysis of the forest fire. In order to apply the analysis conditions, it is researched the forest conditions that is generally distributed in domestic region. As the result, the maximum effect distances by radiant heat were showed at the horizontal and vertical direction. When the wind velocity varied from 0 to 10 m/s, the maximum effect distance increased as the wind velocity increases. Interesting point is that the maximum effect distance were shown at the wind velocity of 8 m/s. The maximum effect distance was decreased according as the fuel moisture of trees increase. This study can contribute to analyse quantitative risk about the damage effect of the surrounding facilities caused by wildland fire.

• Journal of Applied Biological Chemistry
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• v.62 no.4
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• pp.407-415
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• 2019

The biological half-life of pesticides applied on crops is the key indicator for ensuring the safety of agricultural products. The biological half-life is affected by the several factors like growing conditions of the crop, climate, application method, and physicochemical properties of pesticides. In this study, the biological half-life was calculated and the degradation rates of six triazole fungicides sprayed on perilla leaves were evaluated. Moreover, the statistical analysis confirmed the correlation between the biological half-life and physicochemical properties of six triazole pesticides. The recoveries of the six pesticides were between 84.8-104.9%, which satisfied the residual pesticide analysis criteria. The biological half-life of six pesticides sprayed on perilla leaves, calculated using the first-order kinetics model, ranged between 6.4-15.1 days. When the biological half-life and the physicochemical properties were correlated using the principal component analysis: pKa and Log P, the biological half-life was found to be affected by PC1. The correlation coefficient between biological half-life and physicochemical properties (pKa), calculated by Spearman rank-order correlation, was R² = -0.928 (p <0.01). Biological half-life has been shown to correlate with pKa. In conclusion, it can be used as a database for the relationship between biological half-life and physicochemical properties and will contribute to ensure safe supply of agricultural products.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.6
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• pp.541-547
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• 2017

Climate change has become the main cause of the exacerbation in natural disasters. Social Overhead Capital(SOC) structure needs to be checked for displacement and crack periodically to prevent damage and the collapse caused by natural disaster and ensure the safety. For efficient structure maintenance, the optical image technology is applied to the Structure Health Monitoring(SHM). However, optical image is sensitive to environmental factors. So it is necessary to verify its validity. In this paper, the accuracy of estimating the vertical displacement was verified with respect to environmental condition such as natural light, measurement distance, and the number of image sheets. The result of experiments showed that the effect of natural light on accuracy of estimating vertical displacement was the greatest of all. The measurement angle which was affected by the change in measurement distance was also important to check the vertical displacement. These findings will be taken into account by applying appropriate environmental condition to minimize errors when the bridge was measured by camera. It will also enable the application of optical images to the SHM.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.811-819
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• 2013

This study aims to analyze determinants of mountainous and coastal area's housing value caused by the characteristics of the natural environment. As the current issue of housing value is throwing the spotlight on the climate change recently, environmental features are significantly important than before. There were a lot of studies on the influence of environmental characteristics to the housing price but these studies were mostly dealing with the housing price in especially apartments nearby Han-river in Seoul, South Korea. To have differences with existing studies, environmental characteristics estimating housing value are classified as 8 elements including the view, the wind speed, and the humidity. The result of this study is in following; there were few significant environmental variables in mountainous housing value growth model. This means people living in mountainous area recognize on environmental factors more such as housing or complex characteristics. People living in coastal area are much more sensitive environment variables in their residence value than mountainous area. Especially, the view for the ocean is the most important variable in housing value, and wind speed is second positively significant. Humidity and safety of disaster are negatively significant variables.

• Convergence Security Journal
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• v.12 no.2
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• pp.99-106
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• 2012

March 11, 2010, in Japan located over East Sea of Korea, due to the strong earthquake tsunami, Fukushima Nuclear Power Plant was ceased and exploded resulting in leaking radioactive substances. Even though it was an accident happened in a nation, leaked radioactive substances were spread across the world moving along ocean currents and air current. Our nation also had terror and confusion about radioactive rain after the accident, and even though a year has been passed by after the accident, the problem on the radioactive contamination isn't solved. So to speak, nuclear accident of neighboring country is a threat to our nation but not only Japan but also Chinese ocean across the West Sea has nuclear power plants. Beside threat of nuclear accident of neighboring countries, North Korea in military confrontation is the world 3rd country holding chemical and biological weapons and can spray the biological weapons to South Korea at any time like Yeonpyeong-do bombard provocation in November, 2010. The study is the strategy confronting such threats and grafted artificial rain technology which is weather control technology. Since radioactive substances on radioactive accidents and North Korean biological weapons can differ in the density by the weather condition, only artificial rain technology can remove the threat perfectly but it is worth to try as the method to reduce damage and in the aspect of psychology. To use the artificial rain technology in the aspect of national security to acquire the public safety, research institutes such ADD should fulfill active and symbolic technology research development.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.727-733
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• 2011

A new Korean standard for the determination of Cr(VI) in soils has been officially published as ES 07408.1 in 2009. This analytical method is based on the hot alkaline digestion and colorimetric detection prescribed by U.S. EPA method 3060A and 7196A. The hot alkaline digestion accomplished using 0.28 M $Na_2CO_3$ and 0.5 M NaOH solution (pH 13.4) at $90{\sim}95^{\circ}C$ determines total Cr(VI) in soils extracting all forms of Cr(VI), including water-soluble, adsorbed, precipitated, and mineral-bound chromates. This aggressive alkaline digestion, however, proved to be problematic for certain soils which contain large amounts of soluble humic substances or active manganese oxides. Cr(III) could be oxidized to Cr(VI) by manganese oxides during the strong alkaline extraction, resulting in overestimation (positive error) of Cr(VI). In contrast, Cr(VI) reduction by dissolved humic matter or Fe(II) could occur during the neutralization and acidic colorimetric detection procedure, resulting in underestimation (negative error) of Cr(VI). Futhermore, dissolved humic matter hampered the colorimetric detection of Cr(VI) using UV/Vis spectrophotometer due to the strong coloration of the filtrate, resulting in overestimation (positive error) of Cr(VI). Without understanding the mechanisms of Cr(VI) and Cr(III) transformation during the analysis it could be difficult to operate the experiment in laboratory and to evaluate the Cr(VI) results. For this reason, in this paper we described the theoretical principles and limitations of Cr(VI) analysis and provided useful guidelines for laboratory work and Cr(VI) data analysis.

• Journal of the Society of Disaster Information
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• v.17 no.4
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• pp.667-673
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• 2021

Purpose: The aim of this study is to analyze the trend for the dispatch of the 119 rescue teams to remove the beehive according to the distribution of temperature and time in Busan metropolitan city for 5 years from 2015. Method: From January 2015 to December 2019, 11 fire stations in Busan were dispatched and the source data of rescue and emergency activities were collected. The number of beehive removal dispatches was determined by the Busan Metropolitan Fire Station's jurisdiction over the past five years, and the temperature meteorological factors and honeycomb removal dispatches were analyzed in frequency and percentage. Result: The frequency of dispatch began to increase at an monthly average temperature of more than 20℃ and was higher at 23℃ to 29℃ than other temperature range. The highest frequency of dispatch was 7,900 cases in 2017. In particular, we found that the start timing of the honeycomb removal is getting faster as the year goes by. Gijang-gun had the largest frequency of dispatch, and Haeundae-gu, Geumjeong-gu, and Nam-gu were found to have a higher that. Conclusion: We found that the start timing of the honeycomb removal is getting faster as the year goes by and temperature changes. The results of this study are considered to be useful in future studies of wasps in urban areas.

• Journal of Korean Society of Disaster and Security
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• v.14 no.3
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• pp.29-38
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• 2021

Riverfront facilities are river space facilities used by citizens for the rest and convenience. Recently, although the importance of efficient maintenance of riverfront facilities is increasing, damaging facilities cases are increasing due to frequent floods. Currently, the inspections and diagnosis of river space facilities are limited to the main flood control facilities. And the standards for the maintenance and management of the riverfront facilities are insufficient. Utilization survey, which is the standard for managing river space facilities, is also inefficient in terms of manpower consumption and economic feasibility. This study uses mobile big data to classify river usage and conducts a survey for usability of river facilities to derive economic evaluation for usage performance. In the future, if economical method system that considers safety, usability, and durability is conducted and demanding analysis for each convenience facility is evaluated, it is expected that the efficient maintenance of riverfront facilities is perfomed better and the use of rivers by citizens will further increase.