• Fire Science and Engineering
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• v.33 no.2
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• pp.98-106
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• 2019

As lithium batteries have been used for car navigation systems and as the second battery for black boxes, lithium battery-related car fires have often occurred. In the case a lithium battery is the fire origin, a fire investigation technique has not been established to determine if a battery ignites or whether the lithium battery is damaged by fire. This study introduced car fire cases related to lithium batteries, analyzed the causes of a fire of a lithium battery, and proposed fire investigation techniques to objectively determine if a lithium battery ignites or whether a lithium battery is damaged by fire after external ignition.

• Journal of Sericultural and Entomological Science
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• v.14 no.1
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• pp.1-7
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• 1972

Recently, young mulberry trees grown in the reclaimed hill land are frequently attacted by the die-bark and the buds of the trees developed poorly. In order to learn the cause of the injury mentioned above available boron content in the soils and the bark of young shoots have been analyzed. The results are as follow; Available boron content in the soil of the damaged mulberry fold was 0.3-0.20 ppm, against 0.39-49 ppm in that of healthy mulberry field, and boron in the bark of the damaged trees was 10.63-12.99 ppm, and 18.42-21.02 ppm in that of the healthy trees. The organic matter content and available boron content in soils showed a highly significant possitive correlation. The moisture content in percent in the soil of the damaged mulberry held was 11.16 and 14.22 in that of healthy mulberry field.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.6
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• pp.17-27
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• 2014

Wild boars are one of the major wild life animals of which the number has increased a lot because there has been any predator and/or competitor in the Korean ecosystem. The increase of their number was a cause damaging crops in farm lands during the growing season in South Korea. This study was done to recognize the spatial pattern of farm lands damaged by wild boars. Totally 2,342 farms were known damaged by wild boars in 2012, and used to statistically analyze the perspectives of the farm land damages by wild boars in ArcMap v. 9.3. Damages by wild boars frequently happened in the western part of Gyeongnam Province including Jinju city, Tongyoung city and Namhae county. Most farm lands damaged were located nearby large mountains in this area. It might cause the number of wild boars increased in this area, which could finally stimulate the increase of farm land damaged by the species. Farm land damages by wild boars were also coincident with the preference of wild boars on their food. They preferred crops (e.g., sweet potato and corn) in uplands and rice paddies and orchards. The reason of their preference on rice, upland crops and fruits was related to the efficiency of their getting much more energy in a unit area. Another reason for the species to come into a rice paddy would be that they enjoy mud bath in there for scraping off parasites such as ticks and lice. Wild boars were seemed much overcrowded during the period from July to October when most of crops and fruits get ripen. About three-quarters of total farm land damages happened in this period. This analysis also said that 1,915 fields (81.8% of total targets) appeared within the 100-meter buffer from boundaries of mountain areas. This meant that wild boars were more sensitive to the anthropogenic land uses than we expected. They seemed to conservatively try their feeding activities in farm lands with paying attention to the human activity.

• Fire Science and Engineering
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• v.26 no.3
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• pp.35-39
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• 2012

This paper analyzes the combustion diffusion pattern when a water purifier is artificially ignited outside and inside in order to provide data to examine the cause of fire of a water purifier damaged by fire. The analysis result of the combustion diffusion pattern of a water purifier shows that the combustion diffused at a higher speed when it was ignited inside the purifier than when ignited outside. It took approximately 360 seconds for the water purifier to be half-burned when ignited on the outside, and approximately 180 seconds when ignited from inside. That is, it is thought that the internal combustion speed is higher because the internal ignition causes the generated heat to be accumulated and radiated instantly. It was observed that the water purifier damaged by fire caused by external ignition showed a uniform carbonization pattern and the carbide burned down at the bottom were gradually deposited. The water purifier damaged by internal ignition showed a relatively clear boundary of carbonized surface, which formed a V-pattern. The difference in the combustion patterns presents an objective base from which to determine where the fire started. By the time the purifier was half-burned by fire, the built-in fuse had not melted and the power supply protection device did not operate. In addition, as was found in the case of the fuse damaged by a general fire, carbonization occurred at the metal holder, and it is thought that this fact may be used as a basis from which to determine the cause of a fire.

• Journal of Digital Convergence
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• v.10 no.6
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• pp.205-211
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• 2012

According to the Hebei Spirit incident, 12,547kl of crude oil was spilled into the sea and a total of approximately 40,000 households was damaged. Also, eleven cities and counties including "Taean" were designated as a Special Disaster District by government. Large oil pollution incidents cause severe impact on the change of the surrounding environment as well as destruction of the natural environment of damaged areas. This study analyzes the impacts on the surrounding environment of damaged areas caused by Hebei Spirit oil pollution incident, focusing on the largest damaged county called Taean. Survey was performed with items which are changes in population and local economy, effects on public health, social conflicts and etc. The result of analysis can be used as an important factor to forecast the impact on a damaged area in case of future oil pollution incidents and to establish effective policy of government.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.2
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• pp.99-110
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• 2016

When a riser is damaged, the oil spills to sea. Oil spills cause huge economic losses as well as a destruction of the marine environment. To reduce losses, it is needed to predict spilled oil volume from risers and the excursion of the oil. The present paper simulated the oil spill for a damaged riser using open source libraries, called Open-FOAM. To verify numerical methods, jet flow and Rayleigh-Taylor instability were simulated. The oil spill was simulated for various damaged leak size, spilled oil volume rates, damaged vertical locations of a riser, and current speeds. From results, the maximum excursion of the spilled oil at the certain time was predicted, and a forecasting model for various parameters was suggested.

• Corrosion Science and Technology
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• v.19 no.4
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• pp.189-195
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• 2020

Two air vents situated on a heat transport pipe in district heating system were exposed to the same environment for 10 years. However, one air vent was more corroded than the other. It also had a hole on the top of the front-end pipe. Comparative analysis was performed for these air vents to identify the cause of corrosion and establish countermeasures. Through experimental observation of the damaged part and analyses of powders sampled from air vents, it was found that corrosion was initiated at the top of the front-end pipe. It then spread to the bottom. Energy dispersive X-ray spectroscopy results showed that potassium and chlorine were measured from the corroded product in the damaged air vent derived from rainwater and insulation, respectively. The temperature of the damaged air vent was maintained at 75 ~ 120 ℃ by heating water. Rainwater-soaked insulation around the front-end pipe had been hydrolyzed. Therefore, the damaged air vent was exposed to an environment in which corrosion under insulation could be facilitated. In addition, ion chromatography and inductively coupled plasma measurements indicated that the matrix of the damaged front-end pipe contained a higher manganese content which might have promoted corrosion under insulation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.1
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• pp.143-150
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• 2017

In this study, we intend to integrate the database(DB) method into one logical structure that is related to damage such as cause and type of damages occurring in the DMZ area. We divided the DMZ members into two types, which are classified into qualitative and quantitative aspects based on the current status survey for three years as a study of database construction, So that the actual data can be utilized in future restoration. The database construction through each restoration direction regarding the type of DMZ corruption is as follows. First, we recognized the necessity of restoration of the damaged area of the DMZ, and approached it as a plan to select the damaged mark. Second, DMZ database reconstruction can be used as a restoration of damages, suggesting more information and restoration type through building an ecological database for education and research. Third, in order to maintain and restore restoration of damaged areas continuously at the national level, it is necessary to institutionalize guidelines for reasonable internal restoration in the national level as data that can be credited externally and can be acknowledged as the latest data.

• Journal of Sericultural and Entomological Science
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• v.25 no.2
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• pp.32-36
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• 1984

This study was conducted out to evaluate the efficacy of insecticides, furadan (3%G), disyston(5%G), ortran (50%WP), pirimor (50%EC) and metasystox (25%EC) to the mulberry thrips(Pseudodendrothrips mori NIWA.) The comparisons between damaged by thrips and controlled leaves with the cocoon producion and the chemical contents in leaves were carried. The results were as follows; 1. Ortran, furadan and matasystox showed the good efficacy to control the thrips, especially the period of efficacy was the longest in ortran and furadan. 2. The cocoon yield increased in the controlled plot by 3.68kg/box and 5.15kg/10a more than in the damaged plot in autumn rearing season. 3. The content of total carbohydrate and water in mulberry leaves was clearly higher in the controlled plot than in the damaged plot. This may cause the earlier leave harding by damage in autumn.

• KIEAE Journal
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• v.7 no.4
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• pp.141-146
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• 2007

It is necessary to guarantee the safety, serviceability and durability of reinforced concrete structures over their service life. However, concrete structures represent a decrease in their durability due to the effects of external environments according to the passage of time, and such degradation in durability can cause structural degradation in materials. In concrete structures, some degradations in durability increase the corrosion of embedded rebars and also decrease the structural performance of materials. Thus, the structural condition assessment of RC materials damaged by corrosion of rebars becomes an important factor that judges needs to apply restoration. In order to detect the damage of reinforced concrete structures, a visual inspection, a nondestructive evaluation method(NDE) and a specific loading test have been employed. However, obscurities for visual inspection and inaccessible members raise difficulty in evaluating structure condition. For these reasons, detection of location and quantification of the damage in structures via structural response have been one of the very important topics in system identification research. The main objective of this project is to develope a methodologies for the damage identification via static responses of the members damaged by durability. Six reinforced concrete beams with variables of corrosion position and corrosion width were fabricated and the damage detections of corroded RC beams were performed by the optimization and the conjugate beam methods using static deflection. In results it is proved that the conjugate beam method could predict the damage of RC members practically.