• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.66 no.6
• /
• pp.916-922
• /
• 2017

Security systems for inland cargo truck transportation are mostly limited to route tracking for safe and efficient transportation. With this route tracking system, the status of cargo trucks can be monitored easily within inland boundaries. In case of oil transportation by land, however, security systems ensuring transportation of a designated quantity of products have been subject to extensive research since thefts and substitution by a similar product in the transportation process have emerged as a social problem. Security devices installed in an oil tank truck must meet the explosion-proof performance standards and be applicable to varying types of trucks. Accordingly, a wireless electronic seal with RF communication functions is considered to be the most appropriate method, but e-seals on moving vehicles require such levels of performance and reliability that can overcome certain challenges including changing radio waves and topographical impediments. Considering these characteristics of oil tank trucks, this study proposes an stabilization method to enhance the RF communication performance of e-seals, based on radio simulation and experiment findings.

• Journal of the Korean Society of Safety
• /
• v.19 no.1
• /
• pp.66-71
• /
• 2004

This paper describes that the improved effects on the ignition limit are studied by parallel safety components for propane-air 5.25vol.% mixture gas in low voltage inductive circuits. The experimental devices are used in the IEC type spark ignition test apparatus. The improved effects on the ignition limit are respectively obtained as the maximum rising rate of 650%, 1,080% by composing parallel circuits between inductance and safety components (condenser and diode) as compared with disconnecting inductance with the safety components. The more values of inductance the higher improved effects of ignition limit rise. This improving method for the ignition limit is not concerned with the safety components. Diode appears to effect greatly better than condenser. It is considered that the result can be used for not only data for researches and development of intrinsically safe explosion-proof machines which are applied equipment and detectors used in hazardous areas but also for data for its equipment tests.

• Fire Science and Engineering
• /
• v.18 no.1
• /
• pp.18-23
• /
• 2004

This paper describes the minimum ignition limits for propane-air 5.25 Vol.% mixture gases in low voltage inductive circiuts. The improved effects on the ignition limit are studied by parallel safety components(resistors) for propane-air 5.25 Vol.% mixture gas in low voltage inductive circuits. The experimental devices used in this test are the IEC type spark ignition test apparatus. The minimum ignition limits are controlled by the values of current in inductive circuit. Energy supplied from electric source is first accumulated at the inductance, it's extra energy is working as ignition source of the explosive gas. The improved effects on the ignition limit are respectively obtained as the maximum rising rate of 330% by composing parallel circuits between inductance and resistor as compared with disconnecting inductance with the safety components. The more values of inductance increase the higher improved effects of ignition limit rise. The less values of resistor the higher improved effects of ignition limit rise. It is considered that the result can be used for not only data for researches and development of intrinsically safe explosion-proof machines which are applied equipment and detectors used in dangerous areas but also for datum for its equipment tests.