• Composites Research
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• v.22 no.6
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• pp.52-62
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• 2009

This paper is for the state of the art of the lightweight protective clothing against the mine, and it covers the preliminary work focused on the appropriate protection, ballistics, convenience, and wearability. It is suggested that the lightweight protective clothing should be fabricated with the laminated materials of high strength woven and non-woven fabrics to reduce the weight and thickness, thus improving the wearability. And partial reinforcement of the protective clothing is necessary to prevent the mortal wound near the important parts of the body without disturbing the arbitrary activity. The composition of the protective clothing should be designed in consideration of easy putting-on and taking-off in addition to easy divesture, which require little motion of the body is in case of serious injury. Additionally, status of the practical technique for high performance and ultra-light hybrid armor material were also described.

• Journal of the Korea Institute of Building Construction
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• v.13 no.5
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• pp.465-473
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• 2013

Concrete is an outstanding material in terms of its impact and blast resistance performance. However, there a limitation of concrete is its risk of collapse due to the brittle failure and spalling. Increasing the thickness of members was used as a method to enhance the protective performance of concrete, despite the resulting inefficient space. To solve this problem, different types of fiber reinforced concrete were developed. Recently, another type of fiber reinforced concrete is also being developed and applied as a material that offers protection against impacts and blasts by increasing the flexural toughness of concrete. In this study, the test was conducted to evaluate the impact resistance performance of fiber reinforced concrete and mortar according to impact of high-velocity projectile. A concrete T-wall was also tested to evaluate its protective performance from fragment by 155mm-thick artillery shell. The test results revealed that improving flexural strength through fiber reinforcement inhibited cracks and spalling of rear, and spalling of front by high-velocity impact. As such, it is expected to improve the protective performance of the T-wall and reduce the thickness of the member.

• The Korean Journal of Community Living Science
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• v.27 no.4
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• pp.891-906
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• 2016

This study examined the working site environment of Korean native cattle raising farmers and their actual condition of wearing personal protective equipment as part of preventing disasters during agricultural work. To this end, 160 Korean cattle raising farmers were surveyed and a site visit was performed on 10 farms. According to an examination of the cattle breeding environment, the major harmful factors were in the following order: fine dust (12.8%), organic feed dust (10.3%), contact with cattle (9.7%), manure (8.2%), germs and viruses (8.1%), harmful gases (7.4), contact with obstacles (6.7), and temperature (6.6%). The current status of the rate of wearing protection was in the order of gloves (20.9%), working hats (19.7%), boots (19.6%), masks (10.9%), protective clothing (8.9%), and specialized working clothing (6.6%). Nevertheless, most Korean cattle raising farmers recognized the risks when they did not wear protective equipment and the need for wearing protectors, but they mostly did not wear personal protective equipment due to a lack of knowledge on the selection of appropriate personal protective equipment and the discomfort they experience when they put on protectors. Even when they put on protective equipment, 38% was inappropriate for the farming work environment. Given the research results, improvements on and the development of specialized working clothing and personal protective equipment to protect farmers from harmful and dangerous materials from the cattle nurturing environment is necessary. Overall, based on the study data, objectified data collection, a determination of the necessary performance elements of personal protective equipment, and R&D will be needed through an on-site current status investigation.

• Korean Journal of Environmental Agriculture
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• v.35 no.4
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• pp.263-269
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• 2016

BACKGROUND: The personal protective equipments (PPEs) is the most important factor for reducing the pesticide exposure during the preparation and spraying of pesticides. This study was to investigate the retention, repellence and penetration of protective clothing of PPEs according to the ISO 22608 'Liquid penetration resistance-pipette test. Protective clothing for agriculture worker is very important for their health. However, test method for measurement of protective clothing is not presented in Korea. METHODS AND RESULTS: In order to measure the retention, repellence and penetration of protective clothing, a apparatus for pipette method in accordance with the ISO Guideline was prepared. The test was conducted at $25{\pm}5^{\circ}C$, $60{\pm}10%$ of relative humidity and pipette applied to a apparatus was validated to take exact amount(0.2 mL). The retention, repellence and penetration of five types of protective clothing and one type of shirt were analyzed by GC/MS. Pendimethalin(5% a.i, emulsion) was used as a test pesticide to measure above factors. The retention were less than 11.0% with the exclusion of two types(F4 and shirt) and the repellency was more than 67.0% with the exclusion of shirt material. The penetration was less than 5.4%, however, that of shirt was 66.7%. CONCLUSION: This results indicated that all protective clothing were suitable to use as PPEs according to the criteria specified by ISO Guide 22608. However, shirt was not suitable due to high penetration. This test method established for measurement the retention, repellence and penetration of protective clothing will help to establish the test notice of pipette method.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.890-893
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• 2001

Two-layer self bonding insulating tape consists of butyl rubber(IIR ; Isobutylene-isoprene rubber) adhesive layer and polyethylene protective film. Butyl rubber have inherent characteristics such as resistance to corrosion and water, low temperature flexibility, excellent electrical insulating properties also resistance to environmental effect such as ozone and ultraviolet. Polyethylene film was used for the purpose of good insulating properties and resistance to ozone and ultraviolet. The tape was manufactured using extrusion and calender method.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.657-658
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• 2005

Flame retard of polymers was studied for prevention from burning by various additives stimulated the char formation during heating and thermal degradation of polymer materials. Forming char have high porosity, low thermal conductivity and act as thermal shield for heat transmission from the flame to the polymer and. oxygen towards the polymer. The results showed that various additives may regulate the processes of intumecsence. The efficient fire protective intumescent char was result of processes of melting, gas evolution, cross-linking, carbonization etc.

• Journal of Microbiology and Biotechnology
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• v.28 no.1
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• pp.40-49
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• 2018

We evaluated the antioxidant activity and neuronal cell-protective effect of fucoidan extract from Ecklonia cava (FEC) on hydrogen peroxide ($H_2O_2$)-induced cytotoxicity in PC-12 and MC-IXC cells to assess its protective effect against oxidative stress. Antioxidant activities were examined using the ABTS radical scavenging activity and malondialdehyde-inhibitory effect, and the results showed that FEC had significant antioxidant activity. Intracellular ROS contents and neuronal cell viability were investigated using the DCF-DA assay and MTT reduction assay. FEC also showed remarkable neuronal cell-protective effect compared with vitamin C as a positive control for both $H_2O_2$-treated PC-12 and MC-IXC cells. Based on the neuronal cell-protective effects, mitochondrial function was analyzed in PC-12 cells, and FEC significantly restored mitochondrial damage by increasing the mitochondrial membrane potential (${\Delta}{\Psi}m$) and ATP levels and regulating mitochondrial-mediated proteins (p-AMPK and BAX). Finally, the inhibitory effects against acetylcholinesterase (AChE), which is a critical hydrolyzing enzyme of the neurotransmitter acetylcholine in the cholinergic system, were investigated ($IC_{50}$ value = 1.3 mg/ml) and showed a mixed (competitive and noncompetitive) pattern of inhibition. Our findings suggest that FEC may be used as a potential material for alleviating oxidative stress-induced neuronal damage by regulating mitochondrial function and AChE inhibition.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.929-930
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• 2009

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.5
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• pp.391-395
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• 2006

Microcapsules containing fragrant oils as a core material were prepared by in situ polymerization, using melamine-formaldehyde prepolymer as the wall material. The several parameters, such as stirring times, stirring rates, emulsifier types, emulsifier concentrations, and the viscosity of the core materials, affect the characteristics of the microcapsules. These parameters were investigated by the analyses of microcapsule size, particle size distribution, and morphology. The average microcapsule size decreased with an increase in stirring time, stirring rate, emulsifier concentration, and viscosity of the core material. It was also found that poly(vinyl alcohol) as a protective colloid could enhance the stability of the melamine-formaldehyde microcapsules.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.3
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• pp.179-189
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• 2001

This study was performed to identify the current status of work environment management and to provide appropriate recommendations for small scale industry with less than 5 workers from September, 2000 to October, 2000 in Seoul city and Gyoung-gi province. The 211 companies were surveyed by checklist included the elements of management of work environment, hazardous chemicals, MSDS, personal protective equipment, and ventilation system. The proportion of metal products manufacturing and printing industries are 25.6 % and 22.3%, respectively. The daily working hours in printing industry is longer than others. The industries that produce potentially hazardous agents, such as noise, dust, metal, organic solvents, radiation and chemical material are pulp, plating, machinery, and printing, respectively. In above industries, only 2.8 % of those recognised and had MSDS. The proportion of companies providing fire extinguishers, safety showers are found to be 13.3 %, 7.1 %, respectively. Only 24.2 % of companies provided personal protective equipment to the workers. The ventilation system was operated in most of companies. But local exhaust ventilation system is provided to 22.3 % of those, also had not been annually inspected. This study showed that the current status of occupational safety and health was not appropriate for workers in small scale industries. It is suggested that annual physical examination have to be performed, MSDS usage must become widespread, and employer and emplyees in small scale industry should be educated for the treatment and storage of hazardous chemicals to improve the occupational safety and health of the working environment. also, regulatory standard has to be applied to local exhaust ventilation system in small scale industry to improve the working condition.