• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.7
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• pp.897-903
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• 2010

Used gas to the vehicle fuel are the problems of the 'survival' beyond the 'quality of life' improvements and revive a new paradigm of 'sustainable development' which pursues economic development in harmony with environmental conservation. However, the fatalities caused by explosions and fires increases every year with the increase in the use of LPG; gas accidents in large-scale storage facilities also cause severe damage to property. In this study, a suitable storage tank is designed in which the surface area of the fuel exposed to flames is minimized in order to prevent explosions; thus, the occurrences of explosions in underground storage tanks can be minimized. According to the optimum design of storage tank obtained in this study, underground containment space was minimized; the minimized diameter and length of a 20-ton storage tank was 3 m and 4.83 m, respectively. Thus, safety was ensured since surface area exposed to flames decreased by 89.4%, which is less than the exposed surface area in the currently used storage tanks.

• Korean Security Journal
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• no.11
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• pp.37-60
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• 2006

The area of security service has been maintaining the high growth curve annually by improving security consciousness from increase of the income and the progress of public services's level by the accomplishment in the info-communication field, recently the demand for unmanned security system is extended form commercial purposes into public offices and individual's houses. In addition to, the possible distance of offering services is scheduled to magnify. At the period when security company's influence has been becoming significant, the injustice transaction is the serious factor which obstructs the development of security companies. Therefore, it is urgent thing to devise counterplans to extirpate injustice transactions. There are the legalistic approaches of the breakthroughs against injustice transactions. One thing is settling the standard of the judgment and the other is renovating the provision of injustice transactions. Utilizing the principles of the fair competitions and importing self-obedience programs within the range of trade actions which is permitted by law, acted as the system approach. Moreover, there are such three things which can achieve mutual balances as establishing the range of the permitted action toward business corporations, applying spontaneously the fair competition principles and introducing the system of standard agreements. Gong further, this can establish order of security service areas and control them. Besides, it is possible for every organizations to make and operate the system appropriately by importing the self-observance system.

• Journal of the Korean GEO-environmental Society
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• v.21 no.3
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• pp.5-11
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• 2020

Recently, ground pits that have been occurring frequently in urban areas are hindering traffic flow and causing property damages and loss of human life, acting as factors that are threatening the safety of citizens. Therefore, sunken ground must be quickly restored and provisions must be made for additional damage but current domestic detailed standards regarding ground pits and accurate definitions regarding causes and measures to be taken for reoccurrences are lacking. Restoration methods of sunken ground include backfilling by reusing sunken soil or other fill material and paving the road and while this is the most often used method, this only prevents ground from sinking temporarily and can not serve as a fundamental solution. Also, additional ground pits can occur on ground that is reinforced using this method due to faulty backfill material or faulty hardening. This study used Eco-friendly High-Strength Material (EHSM) as restoration material that can be used in the restoration of underground cavities that have occurred due to ground subsidence to analyze the engineered characteristics of modified dredging clay and test pieces made from changed ratios of EHSM and weathered granite soil were uniaxial compression tests were conducted and freezing-thawing tests were conducted to study strength properties according to environmental changes of restoration material, and after tests were concluded by each level, uniaxial compression tests and dynamic elasticity tests were conducted for intensity analysis. Also, to evaluate strength characteristics of the restored ground, dynamic plate load tests were conducted to verify the improvement effectiveness of the restored ground.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.80-87
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• 2018

In recent years, due to the spread of various renewable energy power sources and the pursuit of high efficiency and low-power consumption, not only trends in the electric power industry but also the consumption, control methods, and characteristics are diversified. However, in this diversified electric power industry, the fuse (which is the core part responsible for safety) has not developed significantly in classical operation mode, and thus, fires continue to occur. In this paper, the effects of low melting-point metal plating and high melting-point metal plating on operating characteristics and IT curve movement of the fuse are investigated in a cartridge fuse, which is a classic fuse manufacturing method. The effects of plating on the thickness of the fuse are investigated, and various operating characteristics of the fuse are implemented. In addition, it is suggested that the plating of the low melting-point metal moves the rated current line of the fuse to a low rating, and moves operating characteristics to characteristics of delay operation. It is possible to design various operating characteristics using this characteristic.

• 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.

• Analytical Science and Technology
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• v.24 no.3
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• pp.168-172
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• 2011

The iron frame of building could be collapsed or bent at $500^{\circ}C$. Therefore the fire-resistant paint should be applied for safety. This study performed the comparative analysis to show the characteristics of fireresistant paint. And then 12 products of fire resistant paint and 6 products of paints were used as samples. And the samples were analyzed by TGA (Thermogravimetric Analyzer) as analyzer for measuring the variation of weight on temper of weight by heating. When TGA analyzer could measure the variatiature, and FT-IR was measured for analyze gas components on variation on of weight by heating on 12 products of fire resistance, the samples showed to decrease 40% of weight to $800^{\circ}C$, and because paints had 50% to 40% of loss weight, it showed to be equal with loss weight of fire resistance paint on high temperature or was lower loss weight than it of fire resistance paints. However number 6 sample of fire resistance paints could show to decrease 20% of total weight on $800^{\circ}C$. And then in the case of FT-IR, fire resistance paints could show to have the high intensity of $CO_2$ spectrum as complete combustion. However paints could show to have the lower intensity of $CO_2$ spectrum, have the higher intensity of water spectrum. Therefore the TGA graph of result could be much different until $250^{\circ}C$. When it was burned, FT-IR spectrum could show to confirm the characteristics of fire resistance paints, and the characteristic could be confirmed on inorganic paint of fire resistance by weight loss of TGA.

• Korean Security Journal
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• no.32
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• pp.205-225
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• 2012

This study is to present an improvement of facility security through the evaluation of facility security operation level. To fulfill the purpose of the study, a survey of some facilities was conducted and the result was analyzed as follows; First, although security personnels were deployed in the facilities, the level of security personnel operation was relatively low. Second, job education training level was relatively proper, that is relevant to the result that show the level of service mind and the working mind of security personnel were proper, also relevant to the relatively good work shift system. Third, although situation room was operated well, the level of restricted area set-up and access control of visitor were low, and the level of article inspection and vehicle access control were very low. Forth, the level of security manual application that include detailed security method and procedure was proper. But accident prevention and response manual application was lower than security manual application, that show preparation for fire and negligent-accident is passive. For the improvement of facility security, the high level part and low level part in the survey result could be merged. For example, we could specify factors that show low level in the survey such as security personnel operation, access control of visitor and vehicle, article inspection, accident prevention and response in the security manual and promote education circumstance that show high level.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.6
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• pp.397-405
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• 2012

In this study, performance evaluation of newly developed technology for the economical and safe removal of volatile organic compounds (VOCs) coming out from electronic devices washing operation and offensive odor induction materials was made. Metal oxidization catalyst has shown 50% of removal efficiency at the temperature of $220^{\circ}C$. Composite metal oxidization catalyst applied in this study has shown that the actual catalysis has started at the temperature of $100^{\circ}C$. Comprehensive analysis on the catalyst property using Mn-Cu metal oxidization catalyst in the pilot-scale unit was made and the removal efficiency was variable with temperature and space velocity. Full-scale unit developed based on the pilot-scale unit operation has shown 95% of removal efficiency at the temperature of $160^{\circ}C$. Optimum elimination effective rates for the space velocity was found to be $6,000hr^{-1}$. The most appropriate processing treatment range for the inflow concentration of VOCs was between 200 ppm to 4,000 ppm. Catalyst control temperature showed high destruction efficiency at $150{\sim}200^{\circ}C$ degrees Celsius in 90~99%. External heat source was not necessary due to the self-heat reaction incase of VOCs inflow concentration is more than 1,000 ppm. Equipment and fuel costs compared to the conventional RTO/RCO method can be reduced by 50% and 75% respectively. And it was checked when there was poisoning for sulfide and acid gas.

• Korean Journal of Plant Resources
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• v.30 no.1
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• pp.110-123
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• 2017

The authors reviewed the history of creation and management, purposes, extents, methods of creation, planting species and mediums, structure of vegetation layers and legal management, etc. of coastal forests of Korea. Since the Goryeo dynasty, the inhabitants in the coastal regions has long been aware the safety from natural disasters and the local governments manages for the defence and natural disasters, and collaboration among GO and NGOs, as well as enterprises are participating to the conservation of coastal forests in Korea. The purposes of creation and management of coastal forests in historical aspects are prevention of disasters, safety by the Fengsui, military uses, and timber productions, but partly as the places for religious beliefs, safety from diseases and fires, increasing of forest products and fishes, as well as tourists, improving of amenity and landscapes and recreation, inherits of traditional culture, habitats for wildlife, and ecological corridors, etc. The inhabitant in the coastal region who experienced frequent natural disasters has strong supports for the conservation of coastal forest and as a natural resources to inherits to the coming generations as the coastal forests has high values of academic researches on human society, culture, ecology and recreational uses, etc. The extensive overall researches on the creation and managements of coastal forests, as well as cultural tradition in the coastal forests of Korean peninsula are critically essential.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.2
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• pp.245-250
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• 2017

From the instant of installation and operation, power cables start deteriorating. Cable systems can be maintained not only by monitoring the insulation status of the insulation layer and oversheath, but also the insulation status of the terminal and junction in high-voltage power cables. When the cable system (the cable itself and cable junctions combined) deteriorates, fire accidents happen due to dielectric breakdowns. We have invented a device to monitor the deteriorating status of cables, and installed it at Korea Western Power Co. Ltd. located in Taean, Chungcheongnam-do Province. In this paper, we present the results obtained using our device, through analysing and calculating the standard deviation of leakage current from cable insulators attached to the cables. When the standard deviation of analysed leakage current falls below a critical value, a cable system is deemed to be operating safely. But when the standard deviation of analysed leakage current is larger than the critical value, the insulation status of the terminal and junction in the cable system is considered to have seriously deteriorated. The terminal and junction in the relevant system should then be replaced preemptively in order to prevent blackout accidents of cables caused by the suspension of power supply.