• Journal of Biosystems Engineering
• /
• v.26 no.4
• /
• pp.331-336
• /
• 2001

This study was to develop a kerosene flame weeder. An air compressor was driven though the PTO of a tractor to provide necessary air for fuel combustion and proper pressure to supply fuel from fuel tank to the nozzle. It was found that the flame was extinguished very easily by wind and vibration of the tractor. This trouble could be solved by attaching a burner cap, which is a modified venturi tube, at the end of the nozzle. The constructed flame weeder was tested for the weeding capability in the prepared field. Weed extinction rate and weight decrease rate were analysed. Measured maximum flame temperature was 1,121$\^{C}$ when the fuel consumption was 13.41 kg/h and fuel supply pressure was 88.2 kPa. The maximum temperature occurred at 20cm from the front end the burner, and it decreased to 46$\^{C}$ as the distance increased to 110cm. The flame length of up to 70cm, where the flame temperature was higher than 372$\^{C}$, would be used for weeding purpose. Weed extinction rate and weight decreasing rate increased as the fuel consumption increased. The flame weeder was evaluated to be a practical weeder through improvement as the weed extinction rate and weight decrease rate were analysed to be 75% and 85%, respectively when the fuel consumption was 116.87kg/ha.

• Proceedings of the KSME Conference
• /
• 2008.11b
• /
• pp.2192-2197
• /
• 2008

An experimental study was performed to investigate the effects of configuration of burner and air excess ratio on CO & NOx emission characteristics of the cooktop burners which are used extensively. In this study, the combustion characteristics were investigated with the variation of design factor of cooktop burners. The results showed that as the thermal input increases, flammable region go narrower. With the increase of loading height from the cap to grate, the CO emission decrease owing to the reduction of quenching by flame impingement on the load. Additionally, the CO emission increase with angle of main slot, however the NO emission is almost unaffected.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.20 no.4
• /
• pp.41-56
• /
• 2018

The purposes of this study were to investigate preference of Baekje culture relics and to examine purchasing behaviors of fashion cultural products of adolescents. The subjects were 421 adolescents and measuring instruments consisted of Baekje relics preference items, fashion cultural products purchasing behaviors items, and subject' demographic attributions. The data were analyzed by frequency analysis, $x^2$ test, factor analysis, t-test, ANOVA and Duncan's multiple range test using SPSS program. The results were as follows. First, adolescents were more likely to prefer crown ornaments of the King Muryong in Kongju region, and gilt-bronze incense burner and halo in Buyeo region. Second, as fashion cultural products, adolescents were more likely to prefer T-shirts and accessory items, and modern image. As product selection criteria, they considered aesthetics as the most important factor, followed by symbolism and practicality. Adolescents evaluated the resonable purchase price of fashion cultural products as less than 20,000 won for T-shirts, cap & bag, and less than 10,000 won for accessories. The adolescent's satisfaction of fashion cultural products was low, and the main dissatisfaction was high prices, and the lack of practicality and diversity. Third, the preference for Baekje cultural relics and purchasing behaviors of fashion cultural products differed according to age and sex of adolescents. This study showed that fashion culture products for adolescents need to be designed in a modern sense with a unique cultural symbolism, focusing on T-shirts and accessories items. In addition, fashion cultural products companies should established the product development plan considering the characteristics according to the age and sex of adolescents.