ABSTRACT
OBJECTIVE: Objective data on farmers' awareness of occupational safety and health are needed for the development of national policy measures. Yet, relevant research is lacking in South Korea. METHODS: This study investigated occupational safety and health education experience, perceived needs for prevention services, and factors affecting these among South Korean farmers. The data are from a personal-visit survey conducted on 9,970 sample farms nationwide. RESULTS: While 69.9% of the farmers felt the need for agricultural health and safety education and 60.6% were willing to receive it, only 30.3% had at least one educational experience. A total of 51.9% felt the need for professional on-farm services. By group, education experience and perceived need for prevention services were consistently low among women, people aged 70 or older, low-income individuals, or farmers with a farming career duration of less than five years. Experience of safety and health education increased the desire for other prevention services: people who had received safety and health education were 6.4 times more likely to feel the need for education, 5.5 times more willing to participate in education, 2.0 times more likely to feel the need to improve their work environments, and 1.7 times more likely to feel the need for professional on-farm services. CONCLUSION: Despite the high desire for injury prevention services, farmers have had very limited opportunities to receive safety education; measures are also needed for groups whose safety education has been neglected. Further studies on education methods and on-farm services tailored to South Korean farmers are needed.
Subject(s)
Farmers , Occupational Health , Agriculture , Farms , Female , Health Education , Humans , Republic of KoreaABSTRACT
With the rapid growth in the miniaturization and integration of modern electronics, the dissipation of heat that would otherwise degrade the device efficiency and lifetime is a continuing challenge. In this respect, boron nitride nanosheets (BNNS) are of significant attraction as fillers for high thermal conductivity nanocomposites due to their high thermal stability, electrical insulation, and relatively high coefficient of thermal conductivity. Herein, the ambient plasma treatment of BNNS (PBNNS) for various treatment times is described for use as a reinforcement in epoxy nanocomposites. The PBNNS-loaded epoxy nanocomposites are successfully manufactured in order to investigate the thermal conductivity and fracture toughness. The results indicate that the PBNNS/epoxy nanocomposites subjected to 7 min plasma treatment exhibit the highest thermal conductivity and fracture toughness, with enhancements of 44 and 110%, respectively, compared to the neat nanocomposites. With these enhancements, the increases in surface free energy and wettability of the PBNNS/epoxy nanocomposites are shown to be attributable to the enhanced interfacial adhesion between the filler and matrix. It is demonstrated that the ambient plasma treatments enable the development of highly dispersed conductive networks in the PBNNS epoxy system.
ABSTRACT
Copper is a low-cost material compared to silver and gold, having high reflectivity in the near infrared spectral range as well as good electrical and thermal conductivity. Its properties make it a good candidate for metal-based low-cost multilayer thin-film devices and optical components. However, its high reflectance in the devices is reduced because copper is easily oxidized. Here, we suggest a copper-based Fabry-Perot optical filter consisting of a thin dielectric layer stacked between two copper films, which can realize low-cost production compared to a conventional silver-based etalon filter. The reduced performance due to the inherent oxidation of the copper surface can be overcome by passivating the copper films with monolayer graphene. The anti-oxidation of copper film is investigated by optical microscopy, x-ray photoelectron spectroscopy, and transmission measurement in UV-vi spectral ranges. Our results show that the graphene coating can be expanded for various metal-based optical devices in terms of anti-corrosion.
