| dc.description.abstract | Storing incompatible chemicals can results in great risk. Therefore, determining chemical compatibilities is very important in chemical storage. Traditionally, managers use charts, labels, or simply, texts to do that. But when not enough training or careless occurs, incompatible chemicals can be put together and cause potential risk to accidents. Therefore, developing a system that can automatically identify chemical’s compatibilities is very important. And this research is dedicated to use wireless communication technology to achieve that goal.
Basically, the system uses a communication sensing unit (CSU) to talk to other CSU(s) in the same communication fields. If other CSU(s) do exist nearby and is incompatible to it, an audio alarm will be triggered to notice the manager. In this study, we have developed the WAU protocol for the CSU and it has three features. First, the CSU could join or leave the CSU communication groups (CSU Groups) in any time. Second, the CSU could organize themselves by the no-master-and-no-slave communication protocol, and setting communication timeslot by predefined timeframes which is associated with the incompatibility table.
This research successful developed the CSU with the size of 67mm * 64mm by using NORDIC nRF24E1 as the radio transceiver. The CSU uses two 1.5v AA batteries to drive buzzer, LED and the radio. And it weights about 100g.Under a thousand simulations in the laboratory, a CSU could communicate with other eight CSUs at least one time in 4.85±4 seconds, and no error has been found this test. Power consumption tests showed that the CSU used 27.5 mA during communication and consumed less than 0.01 mA in power down mode. This means that the CSU can be used continuously for about 200 days at 1% communication density if two 2000mA Ni-MH batteries are used. And it is long enough for many waste chemical storage conditions in campus. | en_US |