• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.7
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• pp.88-94
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• 2018

This study examined the safety of a cable stayed bridge caused by damage to the cable system. Many cable-supported bridges, including cable-stayed bridges and suspension bridges, have been constructed on the Korean peninsula. This requires efficient maintenance and management because this structure has complex structural components and systems. This large structure also often faces risks either from manmade causes or natural phenomena. In 2015, the cables on one cable-stayed bridge in South Korea was struck by lightning, which led to a fire on the cables. These cables were damaged, which put the bridge at risk. This bridge was back in use after a few weeks of investigations and replacements of the cables but this was done at enormous social and economic expense. After this event, risk-based management for infrastructure is required by public demand. Therefore, this study examined the risks on the cable system due to potential damage. In this paper, a one cable-stayed bridge in South Korea was selected and its safety was investigated based on the damage scenarios of cable system for efficient and prompt management, and to support decision making. FEM analysis was conducted to evaluate the safety of the bridges after damage to the cable system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.6
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• pp.2833-2845
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• 2012

In this study, the amount of waste resource that could be recovered was analyzed. The installation and operation costs of waste resource recovery for both single- and multi-regional facility were calculated, and compared with the costs of landfill to investigate the feasibility of them. RDF(Refuse Derived Fuel) process and resource recovery by incineration process were considered as waste resource recovery facility. And, the multi-regions for cost analysis were established on the basis of the proper generation rate of municipal waste with the consideration of combustible ratio. The study results showed that single region facility for both RDF and incineration process has no economic benefit, compared with the landfill method. For the multi-regional facility, RDF process could save a large cost than the landfill method, but the incineration facility couldn't. Separate from the economic benefits, the waste resource recovery should be importantly considered when considering the depletion of fossil fuel, global warming, environmental toxicity, and the enormous expenses due to social conflict and confuse. When the CDM(Clean Development Mechanism) is vitalized in the near future, the additional economic benefits by CERs(Certified Emission Reductions) could be expected. CERs for RDF facility is corresponding to about 256.5 billion won, and CERs for incineration facility is corresponding to about 54 and 77.4 billion won for single- and multi-regional facility, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.629-634
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• 2016

In this study, we investigated the effect of factors that influence the measurement of smoke density using synthetic rubber flooring. The characteristics of rolling stock in an enclosed environment can cause enormous loss of life by smoke inhalation during fires inside passenger cars. The amount of smoke generation from interior materials for rolling stock is strictly restricted domestically and in other countries. Precise measurement of smoke density is therefore required to assess the fire performance of interior materials. Major factors that influence the measurement of smoke density include the uniformity of the specimen, the variations in conditions and instruments, and the operational and maintenance environment of the instruments. The contribution of factors was analyzed by estimating the uncertainty to investigate the contribution ratios of the major factors. The results show a contribution ratio of about 86% for the variation from the measurement of light transmission using a photomultiplier tube. Thus, this factor was the most representative for the measurement of smoke density. The contribution ratio of the other factors was low at about 11%, including irradiant flux conditions (${\pm}0.5 kW/m^2$) and the influence of the operational and maintenance environment of the instrument. These results were obtained using specimens with high uniformity.

• Korean Journal of Construction Engineering and Management
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• v.14 no.6
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• pp.49-60
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• 2013

Evacuation process has been considered as one of the most important elements to be managed in public facilities. Although the importance is highlighted through numerous literatures, disaster evacuation planning, particularly fire accidents, faces a number of human behavior related limitations for a similar application to different types of facilities/occupants. To overcome the obstacles including complexity in human behaviors, a number of simulation techniques with limited consideration on human behaviors are utilized to predict foreseeable problems in evacuation process. Therefore, this research aims to propose system dynamics models incorporating human behaviors considering different types of occupants under disaster evacuation events. Analysis on emergent human behaviors such as group forming and interactions under urgent situation are conducted based on the main stream theories in social science field. The results suggest the influences of human behavior factors including cooperative intention, information sharing, and mobility change to evacuation behavior. The implications are expected to provide safety consideration at planning/designing phase of buildings and help facility safety managers for evacuation planning with more realistic management approaches.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.376-382
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• 2008

There are many accidents such as fire and explosion in laboratories that have caused a great loss to lives and property in spite of the effort to the enhancement of laboratory safety level for years. Development of laboratory safety management system is a necessary to improve safety level because the accidents of similar types have periodically occurred in laboratories. The laboratory safety management system may reduce many accidents and a serious loss in laboratory. In this study, we summarized major items for a risk management and safety improvement based on the analysis results of various accidents in the laboratories. And then the laboratory safety management system was developed containing a laboratory safety management manual, a laboratory management system, a education management system, a MSDS (material safety data sheet) management system and a laboratory safety audit system. It may have a potential application for the laboratory safety management in the chemical laboratories.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.5
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• pp.563-574
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• 2020

Currently, road tunnels and railroad tunnels are building smoke control systems to emit toxic gases and smoke from fires. Among the various smoke control systems, the transverse smoke control system has the disadvantage that air supply or exhaust is performed on only half of the cross-section, rather than air supply or exhaust on the entire cross-section of the tunnel as air is supplied or exhausted by partitioning the wind path. Therefore, this study analyzed the effect of exhaustion through numerical analysis and scaled model tests on the zoning smoke control system, which improved the limitations of the transverse smoke control system. As a result of the scaled model test, the transverse ventilation system exhibited a 25.6% smoke control rate based on the state where no smoke was controled, and zoning smoke control system showed a smoke control rate of 40.8%. In addition, as a result of numerical analysis, it was found that transverse ventilation system did not control fire smoke spreading from the tunnel and continued to spread. On the other hand, zoning smoke control system was found to be smoke controled within a certain section due to the air curtain effect and the flue gas effect.

• Herbal Formula Science
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• v.20 no.2
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• pp.177-186
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• 2012

In this study, we selected some herbal formulation about a series of Chijasi-tang in Dongeuibogam by using web-based open program;Prescription Lineage Graph (http://164.125.206.43/PrescriptionLineageGraph.aspx). And we compared and analyzed the changes of efficacy, major target symptoms of each herbal formulation according to compositional variation of each herbal formulation. Chijasi-tang, first appeared in Sanghanlun, consists of Capejasmine and Fermented soybean, and it is mainly used to treat insomnia due to vexation, heartburn and yellow greasy tongue fur. Capejasmine can clear away irritable feverish sensation in chest by flowing downward the heat, and Fermented soybean can disperse stagnated heat throughout the chest by expelling stagnated heat from the exterior In the case of the heat stagnation caused by relapsing of disease due to overstain, Chisijisil-tang can be used. And if symptom appear more on the upper or exterior than a case of Chisijisil-tang, Seosisi-tang could be more suitable, if half exterior and half interior, Omae-tang could be for it. In addition, if symptom caused by relapsing due to improper diet, Chisijihwang-tang could be proper formulation. In the case of the heat stagnation body inside and jaundice, if it is caused by alcohol, Chijadaehwang-tang could be used for the purpose of urgent purgation, Galchul-tang would be suitable for helping the function of the spleen and the stomach and for treatment of damp-heat of the spleen and the stomach. And if it is caused by pandemic infection, Jangdal-hwan would be good formulation for it. Samhwangseokgo-tang and Yangdokchija-tang could be appropriate formulation for the raging of noxious heat and pathogenic fire caused by febrile disease with toxic yang. Daehwangeum-ja is for severe constipation due to heat-dryness with stagnated fever, Haebaek-tang is appropriate for severe diarrhea due to heat type change of Soeum. According to the result of our investigation, although there are various target causes and symptoms of each herbal formulations, whatever pathogenetic cause is, the stagnated heat in interior side is the basis of symptoms. Therefore, the purpose of including Chijasi-tang in composition of each herbal formulation is treatment of the stagnated heat. For such reason, on the fundamental or ancillary basis of Chijasi-tang plus some herbs for each therapeutic purpose.

• Korean Journal of Remote Sensing
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• v.33 no.5_3
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• pp.889-900
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• 2017

In this study, we analyzed the paper about NIR (Near-Infrared) remote sensing data and systematically summarized the research and application fields of NIR. To do this, we conducted a case study on the use of NIR in domestic journals, and SCI journals in the field of technology development for the last 5 years. After selection, a total of 281 journals were analyzed. For the statistical analysis, the classification was divided into subclasses and the dominant research trends were examined. As a result, the researchers who wrote the papers made the highest score of about 60% or more at university. In the field of application, 50% of land, 30% of environment, and 11% of disaster were distributed on SCI journals. In Korea, on the other hand, 55% of land, 24% of environment and 10% of disasters were distributed. In addition, 17% of the national land management and 8% of the geological / natural resources. Disaster observation using NIR was used for landslide, drought, weather disaster and flood. In particular, meteorological disasters are a result of study on Asian dust. However, there were no results of forest fire detection in Korea. Considering the domestic situation, it seems necessary to carry out additional and active research on this. It is expected that this statistical analysis data will be used as basic data to help expand the NIR technology development and utilization field in Korea in the future.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.41-50
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• 2000

Cement-bonded particleboard is being used as outdoor siding material all over the world, because this composite particularly bears a light weight, high resistance against fire, decay, and crack by cyclic freezing and thawing, anti-shock property, and strength enhancement. Construction systems are currently changing into a frame-building style and wooden houses are being constructed with prefabrication type. Therefore, they require a more durability at outdoor-exposed sides. In this study, the cement hydration property for Korean pine particle, Japanese larch particle and face- and middle layer particles (designated as PB particle below) used in Korean particleboard-manufacturing company was investigated, and the rapid manufacturing characteristics of cement-bonded particleboard by supercritical $CO_2$ curing was evaluated. Korean pine flour showed a good hydration property, however, larch flour showed a bad one. PB particle had a better hydration property than larch flour. The addition of $Na_2SiO_3$ indicated a negative effect on hydration, however, $MgCl_2$ had a positive one. Curing by supercritical $CO_2$ fluid gave a conspicuous enhancement in the performances of cement-bonded particleboards compared to conventional curing. $MgCl_2$ 3%-added PB particle had the highest properties, and $MgCl_2$ 1%-added Korean pine particle had the second class with the conditions of cement/wood ratio of 2.7, a small fraction-screened particle and supercritical curing. On the contrary, the composition of non-hammermilled or large fraction-screened particle at cement/wood ratio of 2.2 was poorer. Also, the feasibility for actual use of 3%-added, small PB particle-screened fraction was greatest of all the conventional curing treatments. Relative superiority of supercritical curing vs. conventional curing at dimensional stability was not so apparent as in strength properties. Through the thermogravimetric analysis, it was ascertained that the peak of a component $CaCO_3$ was highest, and the two weak peaks of calcium silicate hydrate and ettringite and $Ca(OH)_2$ were present in supercritical treatment. Accordingly, it was inferred that the increased formation of carbonates in board contributes to strength enhancement.

• Analytical Science and Technology
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• v.13 no.5
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• pp.608-615
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• 2000

A determination method of trace nickel and cobalt in water samples was studied and developed by adsorbing their complexes on ion exchange resin suspension. The analytical ions were formed as complexes with a ligand of APDC (ammonium pyrrolidinedithiocarbamate) and adsorbed on anion exchange resin of Dowex 2-X8. After the suspension was filtered out with membrane filter, the complexes were dissolved in HCl solution by an ultrasonic vibrator for ET-AAS determination. Several conditions were optimized as followings. pH of sample solution: 5.0, amount of ligand APDC: more than 430 times in mole ratio, the type and concentration of acid: 0.1 M HCl, and vibration time: 7 minutes. The addition of palladium in the HCl solution could improve the reproducibility and sensitivity by a matrix modification in the absorbance measurement. This procedure was applied for the analysis of three kinds of real water samples. The detection limits equivalent to 3 times standard deviation of blank were Co 0.36 ng/mL and Ni 0.27 ng/mL and recoveries in spiked samples were 99-102% for cobalt and 100-105% for nickel.