• Fire Science and Engineering
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• v.24 no.3
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• pp.131-138
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• 2010

Experimental and numerical studies were conducted to investigate the thermal and chemical characteristics of heptane fires in a full-scale ISO 9705 room. Representative fire conditions were considered for over-ventilated fire (OVF) and under-ventilated fire (UVF). Fuel flow rate and doorway width were changed to create OVF and UVF conditions. Detailed comparisons of temperature and species concentrations between experimental and numerical data were presented in order to validate the predictive performance of FDS (Fire Dynamic Simulator). The OVF and UVF were explicitly characterized with distributions of temperature and product formation measured in the upper layer, as well as combustion efficiency and global equivalence ratio. It was shown that the numerical results provided a quantitatively realistic prediction of the experimental results observed in the OVF conditions. For the UVF, the numerically predicted temperature showed reasonable agreement with the measured temperature. The predicted steady-state volume fractions of $O_2$, $CO_2$, CO and THC also agreed quantitatively with the experimental data. Although there were some limitations to predict accurately the transient behavior in terms of CO production/consumption in the UVF condition, it was concluded that the current FDS was very useful tool to predict the fire characteristics inside the compartment for the OVF and UVF.

• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.57-65
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• 2008

are nanometer or micrometer scale vesicles that can be used as drug delivery carriers. However, plain liposomes are plagued by rapid opsonization, making their circulation time in bloodstream be shortened. In this study, model protein, bovine serum albumin (BSA)-coated liposomes were prepared by coating cationic liposomes with BSA molecules at higher pH than isoelectric point of BSA. The BSA molecules coated on the liposomal surface were denatured by thermal treatment at above 60oC. While both plain and cationic liposomes had about mean particle diameter of 1041 nm, BSA-coated cationic liposomes (BCL) had mean particle diameter of 1091 nm. Encapsulation of model drug, doxorubicin (DOX), in liposomes were carried out by using remote loading method and the loading efficiency of DOX to liposomes was about 90%. The mean particle diameter of BCL did not increase in blood plasma and adsorption of plasma protein was much less than plain or cationic liposomes. These results suggest that BCL can be used as a long-circulating liposomes in bloodstream.

• Clean Technology
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• v.18 no.2
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• pp.216-220
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• 2012

The objective of the present study was to evaluate catalytic performance of a commercial catalyst (Co/$ZrO_2-Al_2O_3$) for the decomposition of perfluorinated chemicals in a pilot scale reactor containing 30 L of catalysts. At a reaction condition of GHSV $1,800h^{-1}$, $T_{95}$ of $SF_6$ was increased from 580 to $610^{\circ}C$ with increasing of $SF_6$ concentration from 1,000 to 10,000 ppm. $T_{95}$ of $SF_6$ in catalytic decomposition was much smaller than that of thermal decomposition ($1,600^{\circ}C$). The 99% conversion of $SF_6$ was maintained for 72 hours a reaction temperature of $650^{\circ}C$. In order to maintain the $SF_6$ conversion more than 99%, it is necessary to operate at a reaction condition of GHSV less than $2,000h^{-1}$. An operating temperature of $710^{\circ}C$ was required to achieve >95% destruction of the $CF_4$, which was much higher than that of catalytic decomposition of $SF_6$.

• Clean Technology
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• v.19 no.4
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• pp.355-369
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• 2013

Economic feasibility is one of the most important factors in energy production from regenerative biomass. From the aspect, biogas from anaerobic digestion of wastewater sludge is regarded as the most economical because of its cheap substrate and additional income from the disposal of waste sludge. Sludge hydrolysis has been regarded as the rate limiting step of anaerobic digestion and many sludge pre-treatment technologies have been developed to accelerate anaerobic sludge digestion for enhanced biogas production. Various sludge pre-treatment technologies including biological, thermo hydrolysis, ultrasonic, and mechanical methods have been applied to full-scale systems. Sludge pre-treatment increased the efficiency of anaerobic digestion by enhancing hydrolysis, reducing residual soilds, and increasing biogas production. This paper introduces the characteristics of various sludge pre-treatment technologies and the energy balance and economic feasibility of each technology were compared to prepare a guideline for the selection of feasible pre-treatment technology. It was estimated that thermophilic digestion and thermal hydrolysis were most economical technology followed by Cell rupture$^{TM}$, OpenCEL$^{TM}$, MicroSludge$^{TM}$, and ultrasound. The cost for waste sludge disposal shares the biggest portion in the economic analysis, therefore, water content of the waste sludge was the most important factor to be controlled.

• Fire Science and Engineering
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• v.30 no.5
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• pp.1-8
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• 2016

Safety management in hazardous areas with potentially explosive gas atmospheres (here in after referred to as hazardous areas) in large scale facilities dealing with combustible or flammable materials at home and abroad is very important (significant) for the coexistence of the company and local society based on business continuity management (BCM) and reliance. For the safety management in hazardous areas, two systems are mainly used: (1) the control system for the prevention of combustible or flammable substances and (2) the explosion proof system for the elimination of ignition sources when flammable gases are leaked to inhibit the transition to fire or explosion accidents. While technology and regulations on explosion proof facilities or devices for electrical ignition sources are well developed and defined, those for thermal ignition sources need to be more developed and established. In this study, the internal combustion engine in hazardous areas was investigated to determine the risk of ignition. For this purpose, document searches were conducted on the relevant international standards and accidents cases and risk analysis reports. In addition, this study assessed the application cases of the diesel engine's safety equipment, such as spark arresters regarding the site of process safety management (PSM) system in central Korea. To practically apply these results to the hydrocarbon industry, the safety management method for explosion prevention in hazardous areas was provided by risk identification for ignition sources of internal combustion engines, such as diesel engines.

• Fire Science and Engineering
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• v.32 no.1
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• pp.89-98
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• 2018

Fire accidents in foreign countries, like the accident in a thermal power plant in Beijing, the accidents in domestic power plants, including Boryeong Power Plant in 2012 and Taean Power Plant in 2016, a disaster in a nuclear power plant in Fukushima in 2011 or the large-scale power failure in California in 2001 are safety accidents related to electric power, which caused losses in the people's stable lives and the countries. Electricity has an absolute impact on the people's life and the economy, so we can easily expect the serious situation affecting economic growth as well as direct damage to the protection of the people's lives and the losses of properties, if there are fire or explosion accidents or radioactive leak because of negligence in safety management, or problems because of natural disasters like an earthquake in power plants that generate electricity. In this study, it was drawn the improvement of the organizations exclusively in charge of firefighting, the operation of a program for the improvement of professional competency, the development of a customized firefighting management system for plants for systematic firefighting safety management and the improvement of the earthquake-proof correspondence system, which has recently become an issue, as measures for improvements through a survey of the actual conditions concerning the necessity of the construction of a firefighting safety management system for power plants with five power generation companies, including Korea Southern Power Co., Ltd., and the persons in charge of firefighting safety Korea Hydro & Nuclear Power Co., Ltd.

• Journal of Acupuncture Research
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• v.23 no.5
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• pp.219-228
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• 2006

Objectives : To observe the effect of acupuncture treatment on Digital Infrared Thermographic Imaging(DITI) in frozen shoulder patients. Methods : 17 voluntary patients received acupuncture treatment on LI15, TE14, GB21 and Master Dong's acupuncture points, Shin-gwan and Gyun-joong, twice a week for 4 weeks. The patients were instructed to practice self exercise during their daily lives. Evaluations were made before treatment, after 1 week of treatment, after 2 weeks, 3 weeks and after 4 weeks of treatment. Constant Shoulder Assessment(CSA), Shoulder Pain and Disability Index(SPADI), Range of Motion(ROM) and the patient's satisfaction concerning the treatment was measured by Visual Analogue Scale(VAS). DITI was measured before treatment and after 4weeks of treatment. The obtained data was analyzed. Results : CSA, SPADI, VAS, adduction and extension showed significant(p<0.05) improvement. Abduction and flexion both improved after 4 weeks of treatment, but the improvement was statistically insignificant(p>0.05). DITI showed improvement but the improvement was insignificant(p>0.05). Conclusion : 4 weeks of acupuncture treatment significantly improved CSA, SPADI, VAS, adduction and extension in frozen shoulder patients(p<0.05). The improvement of abduction and flexion after 4 weeks of acupuncture treatment was insignificant(p>0.05). DITI results improved after 4 weeks of acupuncture treatment. But the change of thermal difference was insignificant(p>0.05).

• Composites Research
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• v.28 no.4
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• pp.212-218
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• 2015

A large composite spar was manufactured using an automatic fiber placement (AFP) machine. To verify its structural performance, the weakest part of the structure, which is called 'corner radius', was tested under bending and examined by finite element analysis. Since the application of AFP machine to composite structure fabrication is still in early stage in Korea, this paper presents the summary of whole process for manufacturing composite spar using AFP machine from mandrel design and analysis to verification test. The deflection and stress by mandrel weight and AFP machine force, thermal deformation and natural frequency were all examined for mandrel design. The target structure was composite C-spar and cured in an autoclave. Test results were compared with nonlinear finite element analysis results to show that the structure has the strength close to the theoretical value. It was confirmed that the corner radius of the spar manufactured by AFP process showed deviation less than 20% compared with first ply failure strength. The results indicate that the AFP technology could be used for large scale composite structure production in the near future.

• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.106-111
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• 2008

Polypropylene (PP)/corn starch master batch (starch-MB)/silicate composites with different corn starch compositions of 10, 20, 30, 40 and 50 were prepared by melt compounding at $200^{\circ}C$, using lab scale Brabender mixer. The content of silicate was fixed at 5 wt%. The composition of starch-MB in composites was confirmed by the existence of hydroxy group and peak intensity in fourier-transform-infrared (FT-IR) spectrum. The thermal properties of the PP/starch-MB/silicate composites were investigated by differential scanning calorimetry (DSC), and thermogravimetric analyzer (TGA). There was no district change in melting temperature, and TGA curve indicates a decrease in degradation temperature with the increase of starch-MB content. The silicate dispersion of the composites was measured by X-ray diffraction (XRD) and transmission electron microscope (TEM). The degree of silicate dispersion in PP/starch-MB/silicate composites depended on the content of starch-MB. There was detectable change in d-spacing and peak intensity of the composite when the content of starch-MB was higher than 20 wt%. The rheological behavior of the composites was explained by both shear thinning effect and elastic property with the starch-MB amount. These effects were remarkable when the content of starch-MB was higher than 20 wt%. These were confirmed by an oscillatory viscometer at $200^{\circ}C$.

• Korean Chemical Engineering Research
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• v.45 no.4
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• pp.311-318
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• 2007

Soil contamination in Korea has been accelerated every year. Because of their persistence and cumulative tendency in the environment, soil contaminants have potential long-term environmental and health concerns and it is estimated to cost enormous expense for clean-up. Korea government has legislated the law on conservation of soil environment in mid 1990s, and managed and treated hazardous wastes in contaminated sites as a remediation policy since then. Soil remediation technologies are classified into in-situ/ex-situ or biological/physico-chemical/thermal processes according to applied places or treatment methods, respectively. In Korea, clean-up of polluted sites has been mostly carried out at military areas, railroad-related sites and small-scale oil spilt sites. For these cases, in-situ remediation technologies such as soil vapor extraction (SVE) and bioventing were mainly used. In recent days, an environmental-friendly soil remediation emerged as a new concept - for example, a new soil remediation process using nanotechnology or molecular biological study and an integrated process which can overcome the limitation of individual process. To have better applicability of remediation technologies, comprehensive understandings about the pollutants and soil characteristics and the suitable techniques are required to be investigated. Above all, development of environmental technologies based on the sustainability accompanied by public attention can improve soil environment in Korea.