• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.4
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• pp.157-167
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• 2002

In most cases, quantity of reinforcement is determined without regard to the difference of initial strain, and status of damages when calculated the strengthening in flexure at beams. Thus, the purpose of this study is to investigate the flexural strengthening efficiency and behavior of RC beams strengthened with carbon fiber sheets(CFS) considering different status of damages. in this paper, a nonlinear analysis program considering rip-off strength and residual stress of steel bars and concrete in different status of damages is developed to predict the flexural behavior of CFS strengthened beams. Rip-off strength equation is obtained by modifying moment of inertia in the Robert's equation. And conformed developed nonlinear analysis program in variable of strengthening CFS amount and status of damages(initial, case1, case2, case3) and tension reinforcement ratio(0.2~1.0%).

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.73-76
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• 2001

This paper dives the current status of lightning damages in apartments obtained by questionnaire and analysis the cause of ligntning damages. As a result, the apartments experienced lightning damages are assumed about 5[%] lot total apartments and the lightning surges invaded on power line are identified as the main cause of lightning damages in apartments.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2007.11a
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• pp.45-47
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• 2007

This paper gives the current status of lightning damages in apartments which are obtained by questionnaire and the cases of lightning damages in Korea. Survey result shows that lightning damages are increasing every year and taking place everywhere not only building but also mountain. As a result advanced lightning protection systems are required to reduce the lightning damages in various structures.

• Journal of the Korea Concrete Institute
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• v.12 no.1
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• pp.69-77
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• 2000

Recently, many strengthening methods are developed to repair damaged structures, when the original structure is under loading, which causes the difference of initial stresses between original member and bonded material. However, current design method or theory, which mostly depends on ultimately strength design, cannot account the difference of initial stresses between members, and it disregards the reduction of nominal strength. In this study, a new strengthening design theory and the amount of strengthening which can account the difference of initial stresses are developed, and applied to the case when a structure in service is repaired. The results show that the amount of strengthening material depends on the status of damages of structure, and the nominal strength is reduced depending on the degree of damages.

• Smart Structures and Systems
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• v.31 no.6
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• pp.573-583
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• 2023

Although unmanned aerial vehicles have been used to overcome the limited accessibility of human-based visual inspection, unresolved issues still remain. Onsite inspectors face difficulty finding previously detected damage locations and tracking their status onsite. For example, an inspector still marks the damage location on a target structure with chalk or drawings while comparing the current status of existing damages to their previous status, as documented onsite. In this study, an augmented-reality-based structural inspection system with onsite damage information marking was developed to enhance the convenience of inspectors. The developed system detects structural damage, creates a holographic marker with damage information on the actual physical damage, and displays the marker onsite via an augmented reality headset. Because inspectors can view a marker with damage information in real time on the display, they can easily identify where the previous damage has occurred and whether the size of the damage is increasing. The performance of the developed system was validated through a field test, demonstrating that the system can enhance convenience by accelerating the inspector's essential tasks such as detecting damages, measuring their size, manually recording their information, and locating previous damages.

• Proceedings of the Korean Nutrition Society Conference
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• 2000.06a
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• pp.132-132
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• 2000

• Journal of the Korea Safety Management & Science
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• v.20 no.1
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• pp.23-31
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• 2018

Industrial disasters cause lots of damages from individuals to companies and country. Especially, damages caused by constructional disasters take very large portion in the whole industry and are accompanied by huge personal physical damages. For the prevention of disasters, roles of safety manager are very important and especially, effects of disaster prevention can be changed by occupational ability of construction safety manager. To improve job abilities of safety manager, job education is very important. This research suggested a model for job education management of construction safety manager and proposed improvements as a study on improvement of curriculum for vitalization of job education of construction safety manager so as to improve occupational ability of safety manager. To achieve them, this research examined standard and operation status of current job education of safety manager and the problems and suggested a model materializing job educational contents as a measure to vitalize job education system of safety manager.

• Journal of the Korea Concrete Institute
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• v.11 no.3
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• pp.35-45
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• 1999

Recently, many strengthening methods are developed to repair damaged structures, especially, steel plate or carbon fiber sheet bonding methods are widely used. For the bonding methods, the strengthening materials are bonded when the original structure is under loading, which causes difference of initial stresses between original member and bonded material. However, current design method or theory, which mostly depends on ultimately strength design, cannot account the difference of initial stresses between members, and it disregards the reduction of nominal strength. In this study, a new strengthening design theory and program which can account the difference of initial stresses are developed, and applied to the case when a structure in service is repaired. In order to verify the validity of the theory and the program, a test result is referred and compared with the results and it is showed that the calculated values are almost same as the referred data and finally proved that the program is reliable. The results showed that the amount of strengthening material depends on the status of damages of structure, and the nominal strength is reduced depending on the degree of damages.

• Journal of Korean Society of Rural Planning
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• v.22 no.2
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• pp.19-29
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• 2016

Disasters that occur most frequently in rural areas are drought, flood, damages from wind and cold weather. Among these, damages from storm and flood and drought are the main disasters and recently, these are occurring on a large scale due to unusual weather conditions. Under such circumstances, projects and researches on disasters in rural areas are under way but they are mostly targeting one area or making approaches focusing on repair facilities, maintenance project of facilities in small streams, and disaster management, so there have not been enough studies on the current status of overall damaged facilities in the rural areas. Against this backdrop, through the analysis of the current status of damaged facilities due to storm and flood in rural areas, this study aims to provide base data for policies needed for disaster recovery planning and maintenance work of rural areas. For the analysis of damaged facilities due to storm and flood in rural areas, using the annual report on disasters issued by Ministry of Public Safety and Security and based on the occurrence rate of estimated damage in each city and district for the past 10 years(2004~2013), 8 areas with the highest number of occurrence and cost of damage were found from each province and target areas were selected. Then, regarding the selected target areas, the General Plan for Reducing Damages from Storm and Flood, which is the report on top-level plan for preventing disasters, was secured and the current status of damaged facilities were analyzed. After organizing the analysis of current status, the tendency of damaged facilities due to storm and flood in rural areas, the items of damaged facilities depending on the types of storm and flood damages, and risk factors were suggested. Based on this result, in order to generalize the results of follow-up researches, it is thought that disaster recovery planning and establishing the system of remodeling items necessary for maintenance work would be possible by analyzing damage investigation items recorded in additional researches on rural areas, researches on natural disasters, and recovery plan instructions and by conducting on-site investigation on the damaged villages from storm and flood in rural areas.

• Nutritional Sciences
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• v.8 no.4
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• pp.262-267
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• 2005

Reactive oxygen species can be generated in the skin by hair dyeing. The aim of this study was to find out the effects of the oxidative-type hair dye application in young women on the antioxidant systems. We investigated the lipid peroxide levels, glutathione (GSH) levels, and the antioxidant enzyme activities including superoxide dismutase (SOD), glutathione peroxidase (GSHPx) in plasma and erythrocytes and catalase (CAT) in erythrocytes, and DNA damages in lymphocytes. Also, plasma concentrations of antioxidant vitamins, vitamin A and E, were measured and the correlations between various antioxidant parameters and oxidative damages were evaluated The antioxidant enzyme activities in plasma (GSHPx) and in erythrocytes (SOD and CAT) were decreased significantly after hair dyeing. 1be lipid peroxide and GSH levels were not affected in both plasma and erythrocytes. No significant difference was found in the concentrations of both vitamin A and E between before and after hair dyeing. However, DNA damages expressed as the tail extent moment (TEM) and tail length (TL) were significantly (p<0.001) increased. The plasma vitamin E concentration was correlated with DNA damages (TEM: r=-0.590, p<0.01 and TL: r=-0.533. p<0.01) and RBC SOD activity (r=0.570, p<0.05). In turn, RBC SOD activity was significantly correlated with both plasma MDA levels (r=-0.412, p<0.05) and DNA damages (TM: r=-0.546, p<0.01, TL: r=-0.493, p<0.01). Our results demonstrated that the exposure to hair dyeing produced lymphocyte DNA damage and modification of the antioxidant enzyme activities. Also, there were very strong associations between plasma vitamin E concentration, RBC SOD activity and DNA damage induced by hair dyeing. It suggests that the antioxidant status of a subject is likely to be related to the extent of the harmful effects caused by hair dyeing.