In this study, we addressed the prevention of fire extinguishing device malfunction caused by noise in the fire detector of automatic fire extinguishing devices applied to mobile equipment such as armored vehicles and tanks. The automatic fire extinguishing system consists of a fire detection unit, an automatic control unit, and a fire suppression unit. In the case of a fire detector, it is a major component of the fire detection unit. Even though no fire occurred during operation in the field, a number of fire extinguisher sprays occurred, and the malfunction of the fire detector, which is a fire detection unit, was reproduced. The cause was identified as noise in the fire detector connector due to vibration and shock that may occur during operation of the mobility equipment. In order to solve this problem, noise generated momentarily from a fire detector is treated as an exception, and when a fire signal is transmitted from the fire detector to the automatic control unit for more than a certain period of time, Software has been improved to enable fire extinguishers to operate. This study analyzed the causes of malfunctions in automatic fire extinguishing devices, which are components of mobile equipment, and derived improvement measures to improve the reliability of automatic fire extinguishing devices.

In this paper, as there are many cases of fires occurring due to the failure or inoperability of the thermostat of electronic products, the purpose is to test and analyze the risks and probabilities through fire cases and reproduction experiments, and suggest countermeasures. Among electronic products, water purifiers are composed of a refrigerant system with a compressor to make cold water, a heating device to make hot water, and an electric device used as an energy source. Due to the nature of the water purifier manufacturing, these devices are subject to a lot of moisture and dust. etc. exist in large quantities and use electrical energy, so there is a possibility of fire due to short circuit in the wire, electrical abnormal overheating (tracking phenomenon) in the thermostat, electronic board, starting relay, etc., and overheating of the heating device (Band Heater). there is. Therefore, in order to prevent fires from these devices, a system to remove foreign substances inside the water purifier is necessary, the use of heat-resistant (fire-resistant) wires for electrical devices is essential, and the use of non-combustible materials (semi-combustible materials) for each part is necessary to prevent fire. The risk must be eliminated through prevention and combustion expansion prevention devices.

While it is well known that space environment can produce spacecraft anomaly, defining space environment effects for each anomalies is difficult. This is caused by the fact that spacecraft anomaly shows various symptoms and reproducing it is impossible. In this study, we try to find the conditions of when spacecraft failures happen more frequently and give satellite operators useful information. Especially, our study focuses on the geosynchronous satellites which cost is high and required high reliability. We used satellite anomaly data given by Satellite News Digest which is internet newspaper providing space industry news. In our analysis, 88 anomaly cases occurred from 1997 to 2008 shows bad corelation with Kp index. Satellite malfunctions were likely to happen in spring and fall and in local time from midnight to dawn. In addition, we found the probability of anomaly increase when high energy electron flux is high. This is more clearly appeared in solar minimum than maximum period