• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.664-668
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• 2018

Free-standing structures that are especially high are more likely to receive brain attacks caused by lightning. Since special structures are generally part of national industrial structures, lightning strikes mostly cause socio-economic damage. Lightning protection facilities are installed to prevent such lightning damage, but in 2015, support cables on West Sea bridges were hit by lightning, causing a lot of economic damage. Accordingly, the design of a lightning protection system shall establish protective measures after analyzing the risk of debris falling onto the structure. In this thesis, lightning strikes are analyzed directly in relation to the modeling system that operates the actual information collection system for lightning strikes, depending on the location of the tall, free-standing structures, and practical lightning hazard information is provided by a meteorological station. In addition, we propose monitoring and applying a probability correction rate to the calculation of the lightning risk based on the number of lightning strikes directly reaching the ground in order to obtain an effective lightning risk assessment.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.4
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• pp.324-329
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• 2020

The emergency evacuation support system provides a safe means of evacuation by preventing the inflow of smoke through the formation of a smoke shield curtain in fire situations and pressurizing fresh air to the inside of the smoke shield curtain. In this study, numerical analysis was performed to examine the effects of the hole size on the flow inside the smoke curtain. As the air supply size decreased, the flow rate through the air supply was formed relatively uniformly from the inlet to the outlet length of the emergency support system. In addition, the size of the air supply hole was more than 20 mm, the flow rate was very low near the outlet, so the air supply hole size should be smaller than 20 mm. In addition, the minor loss of the air supply hole was calculated to be K = 1.5 from the numerical results. Therefore, the proper design of an emergency evacuation support system is possible using the flow characteristics according to the size and minor loss of the air supply hole.

• Journal of Digital Convergence
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• v.16 no.7
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• pp.223-229
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• 2018

Recently, the necessity of safety diagnosis of electrical devices has been increasing as the fire caused by electric devices has increased rapidly. This study is concerned with the safety diagnosis of electric equipment using intelligent Fuzzy technology. It is used as a diagnostic input for the multiple electrical safety factors such as the use current, cumulative use time, deterioration and arc characteristics inherent to the equipment. In order to extract these information in real time, a device composed of various sensor circuits, DSP signal processing, and communication circuit is implemented. The fuzzy logic algorithm using the Gaussian function for each information is designed and compiled to be implemented on a small DSP board. The fuzzy logic receives the four diagnostic information, deduces it by the fuzzy engine, and outputs the overall safety status of the device as a 100-step analog fuzzy value familiar to human sensibility. By experiments of a device that combines hardware and fuzzy algorithm implemented in this study, it is verified that it can be implemented in a small DSP board with human-friendly fuzzy value, diagnosing real-time safety conditions during operation of electric equipment. In the future, we expect to be able to study more intelligent diagnostic systems based on artificial intelligent with AI dedicated Micom.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.2
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• pp.168-176
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• 2017

HNS accidents involve large-scale fires and explosions, causing numerous human casualties and extreme environmental pollution in the surrounding area. The widespread diffusion of effects should be prevented through rapid decision making. In this study, a high-quality, standardized, and digitized HNS accident databases has been generated based on the HNS standard code proposed. Furthermore, the HNS Accident Tracking System (HATS) was applied and implemented to allow for systematic integration management and sharing. In addition, statistical analysis was performed on 76 cases of domestic HNS accident data collected over 23 years using HATS. In Korea, an average of 3.3 HNS accidents occurred each year and major HNS accident factors were Springs (41 %), Aprons (51 %), Chemical Carriers (49 %), Crew's Fault (45 %) and Xylenes (12 %). (The number in parentheses is the percentage of HNS accident factors for each HNS accident classification)

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.791-796
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• 2007

As large-scale buildings, skyscrapers, and multi-purpose buildings recently increase in numbers dramatically, the internal space of such buildings becomes more and more large and complicated accordingly. Since such structures usually accommodate a number of random people, the potential possibilities of disastrous tragedies are high, and the rates of injury and physical damage caused by the complicated system of the building also increase as well. However, most of the shelter designs of the existing buildings are based on the specifications according to the assigned laws and involved regulations. In this case, only general criteria are referred to regardless of the characteristics of each structure while other disaster-related features are not taken into consideration sufficiently. Since any actual fire may cause a terrible calamity, in such plans, shelter inducement can be neither safe nor effective. Thus, this study examines and analyzes currently run disaster prevention systems and shelter inducement facilities with COEX Mall as its subject, and analyzes the responding system to each situation based on the fire scenarios by means of As-Is Model. Through this analysis, presented are the measures to solve the problems of current disaster prevention systems and to improve shelter inducement methods effectively.

• Korean Journal of Heritage: History & Science
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• v.47 no.3
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• pp.4-23
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• 2014

Seokjojeon Hall is the Neoclassic style building situated in Deoksugung Palace, which was proposed by John McLeavy Brown who was a chief commissioner of the Daehan Empire and designed by John Reginald Hardings in 1897. Construction of the Seokjojeon Hall began in 1900 and completed in 1910 at the total cost of one million won. Decorating and furnishing of the interior was designed by Lovell and all the furniture of Seokjojeon Hall had been purchased from Maple&Co. The Maple&Co was the supplier of luxury furnitures and decorating items for luxurious residentials, hotels, embassies and the palaces and its headquarter was located in London. Ready-made furnitures were purchased as shown in the Maple's catalog. The designs and styles of the west were applied to Seokjojeon Hall. That is one of the aspects showing Daehan Imperial underwent a period of Westernization.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.619-625
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• 2019

It is difficult to design because of the plug-holing phenomenon in which the amount of smoke discharged from the vertical vent is smaller than the designed amount of smoke. In this study, the effect of cross-sectional area ratio of tunnel and natural ventilation and heat release rate of fire source on plug-holing phenomenon occurring in natural ventilation system was experimentally analyzed. In the experiment model reduced to 1/20 size, the aspect ratio of the tunnel and the vertical vent was fixed, and the influence on the plug-holing phenomenon was confirmed by varying the sectional area ratio of the tunnel and the vertical vent. Experimental results show that the plug-holing phenomenon is caused by the comparison of the smoke boundary layer temperature with the temperature in the vertical vents, and the flow and temperature distribution characteristics under the vertical vents are changed as the cross-sectional area ratio of the tunnel and vertical vents increases. The plug-holing phenomenon is affected by the cross-sectional area ratio between the tunnel and the vertical ventilation. The greater the cross-sectional area ratio, the greater the probability of plug-holing.

• Korean Chemical Engineering Research
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• v.59 no.4
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• pp.521-531
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• 2021

Vacuum Pressure Impregnation (VPI) is a process that enhances physical properties by coating some types of epoxy resins on windings of stator used in large rotators such as generators and motors. During vacuum and pressurization of the VPI process, resin gas is generated by vaporization of epoxy resin. When the tank is opened for curing after finishing impregnation, resin gas is leaked out of the tank. If the leaked resin gas spreads throughout the workplace, there are safety and environmental problems such as fire, explosion and respiratory problems. So, exhaust system for resin gas is required during the process. In this study, a case study of exhaust efficiency by location of vent was conducted using Computational Fluid Dynamics (CFD) in order to design a system for exhausting resin gas generated by the VPI process. The optimal exhaust system of this study allowed more than 90% of resin gas to be exhausted within 1,800 seconds and reduced the fraction of resin gas below the Low Explosive Limit (LEL).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.867-872
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• 2020

Oil storage tanks are a major structure in chemical industrial complexes. Damage to the structure due to natural disasters or poor management can cause additional damage, such as leakage of chemicals, fire, and explosion, so it is essential to understand the deformation. In this study, data on oil storage tanks were acquired using a 3D laser scanner, and various analyzes were performed for storage tank management by comparing them with design data. Modeling of the oil storage tank was performed using the data and design drawings acquired by a 3D laser scanner. An inspection of the oil storage tank was effectively performed by overlapping. In addition, cross-sectional and exploded views of the deformation were produced to generate visible data on the deformation of the facility, and it was suggested that the oil storage tank had a maximum deformation of -7.16mm through quantitative analysis. Data that can be used for additional work was obtained by producing drawings to be precisely inspected for areas with large deformation. In the future, an inspection of oil storage tanks using 3D laser scanners is quantitative and visible data on oil storage tank deformation. This will greatly improve the efficiency of facility management by rebuilding it.

• KIPS Transactions on Computer and Communication Systems
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• v.10 no.4
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• pp.117-122
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• 2021

In recent years, human damage and loss of money due to various disasters such as typhoons, earthquakes, forest fires, landslides, and wars are steadily occurring, and a lot of manpower and funds are required to prevent and recover them. In this paper, we designed and developed a disaster drone system based on artificial intelligence in order to monitor these various disaster situations in advance and to quickly recognize and respond to disaster occurrence. In this study, multiple disaster drones are used in areas where it is difficult for humans to monitor, and each drone performs an efficient search with an optimal path by applying a deep learning-based optimal path algorithm. In addition, in order to solve the problem of insufficient battery capacity, which is a fundamental problem of drones, the optimal route of each drone is determined using Ant Colony Optimization (ACO) technology. In order to implement the proposed system, it was applied to a forest fire situation among various disaster situations, and a forest fire map was created based on the transmitted data, and a forest fire map was visually shown to the fire fighters dispatched by a drone equipped with a beam projector. In the proposed system, multiple drones can detect a disaster situation in a short time by simultaneously performing optimal path search and object recognition. Based on this research, it can be used to build disaster drone infrastructure, search for victims (sea, mountain, jungle), self-extinguishing fire using drones, and security drones.