• Title/Summary/Keyword: Life Safety

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Assessment of Food Hygiene and Safety Knowledge, Attitudes, and Practice in Elementary School Students

  • Lee, Joo-Yeon;Kim, Jeong-Weon
    • Food Quality and Culture
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    • v.2 no.1
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    • pp.48-54
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    • 2008
  • The purpose of this study was to evaluate the elementary students' knowledge, attitudes, and practice for food hygiene and safety. A self-administered questionnaire was developed and offered to 375 elementary school students throughout the Seoul region. The results of the survey were as follows: First, the knowledge, attitudes, and practice were not at satisfactory level. The scores of children's knowledge, attitudes, and practice were 67.42%, 3.83, and 3.81 out of 5 point scale, respectively. Second, knowledge, attitudes and practice levels were significantly different according to demographic characteristics. The lower grade-students had significantly higher scores for knowledge (p<.05), attitudes (p<.05) and practice (p<.01) than higher gradestudents, suggesting that food hygiene and safety education is more effective in younger students or that repeated education is needed for higher grade-students. Third, knowledge, attitudes and practice levels were significantly correlated each other. These results suggest that the education programs for food hygiene and safety should be developed for, as well as implemented in, lower elementary school grades.

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Development of functional food products with natural materials derived from marine resources (건강기능성 수산식품소재의 개발)

  • Ryu, BoMi;Jeon, You-Jin
    • Food Science and Industry
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    • v.51 no.2
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    • pp.157-164
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    • 2018
  • Recently demand for safer and healthier food has augmented with advancements in health conditions. Food ingredients with yet to be known safety and functionality, are being investigated for their safety or detrimental effects. The Ministry of Food and Drug Safety has introduced "health functional food" by the "Health Functional Food Act" to evaluate bio-functional and safety properties of raw materials using standard methods including in-vitro and in-vivo testing before human consumption. Despite recent growth in net worth of domestic functional food market, most of the raw materials are not from local Korean industries with own research and development, and mostly terrestrial not marine resources. Geographically, Korea has access to diverse marine bio-resources that need to be managed and utilized sustainably. Recently, diverse novel physiologically active substances have been reported from marine organisms. Hence, the development of functional foods from marine bio-resources is considered as an inevitably important task.

Effect of Water Contamination of the Lubricant and Surface Roughness of Bearing Steel on the Rolling Contact Fatigue Life (윤활유의 수분혼입 및 베어링강의 표면 조도가 구름접촉 피로수명에 미치는 효과)

  • Heo, Tae Hyeon;Sim, Chung-Ki;Kim, Hong Seok;Shin, Ki-Hoon;Cheong, Seong Kyun
    • Journal of the Korean Society of Safety
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    • v.32 no.1
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    • pp.15-20
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    • 2017
  • A large amount of research has been performed on the rolling contact fatigue(RCF) life of bearings, since it directly affects the safety and reliability of mechanical systems. It is well known that rolling contact fatigue life is influenced by several parameters including contact pressure, oil contamination by water or metal particles, and the surface conditions of bearings. However, the detailed damage mechanisms involved in rolling contact fatigue have not been clearly identified yet. In this paper the effects of water contamination of the lubricant and surface roughness of bearing steel on the rolling contact fatigue life were investigated. Two types of specimens with different surface roughness values were prepared through turning and lapping operations. They were tested under two different lubrication conditions, i.e. oil lubricant with 100% of oil and the water contaminated condition with 80% of oil and 20% of water using the rolling contact fatigue testing machine. The surface damage induced by the rolling contact fatigue was observed by using atomic force microscope(AFM). Experimental results show that the rolling contact fatigue life, $L_{10}$ was reduced by 24 to 33% depending on the lubrication condition. The reduction of fatigue life in the range of 53 to 57% was also observed at different surface roughness conditions.

Breakdown Characteristics and Lifetime Estimation of Rubber Insulating Gloves Using Statistical Models

  • Kim, Doo Hyun;Kang, Dong Kyu
    • International Journal of Safety
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    • v.1 no.1
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    • pp.36-42
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    • 2002
  • This paper is aimed at predicting the life of rubber insulating gloves under normal operating stresses from relatively rapid test performed at higher stresses. Specimens of rubber insulating gloves are subject to multiple stress conditions, i.e. combined electrical and thermal stresses. Two modes of electrical stress, step voltage stress and constant voltage stress are used in specimen aging. There are two types of test for electrical stress in this experiment: the one is Breakdown Voltage (BDV) test under step voltage stress and thermal stress and the other is lifetime test under constant voltage stress and temperature stress. The ac breakdown voltage defined as the break-down point of insulation that leakage current excesses a limit value, l0mA in this experiment, is determined. Because the very high variability of aging data requires the application of statistical model, Weibull distribution is used to represent the failure times as the straight line on Weibull probability paper. Weibull parameters are deter-mined by three statistical methods i.e. maximum likelihood method, graphical method and least squares method, which employ SAS package, Weibull probability paper and FORTRAN, respectively. Two chosen models for predicting the life under simultaneous electrical and thermal stresses are inverse power model and exponential model. And the constants of life equation for multistress aging are calculated using numerical method, such as Gauss Jordan method etc.. The completion of life equation enables to estimate the life at normal stress based on the data collected from accelerated aging test. Also the comparison of the calculated lifetimes between the inverse power model and the exponential model is carried out. And the lifetimes calculated by three statistical methods with lower voltage than test voltage are compared. The results obtained from the suggested experimental method are presented and discussed.