# Intelligent Environment Monitoring System for University Laboratories
## 4 Real Experiments
### Testing  
Using a DC12 V (5.5 \(\times\) 2.1) power line to supply power to the development board, the system realized the voice reminder \"system boot success\". Other modules were quickly activated with electricity, while the GPRS module had approximately one minute's start time.  
In a 10 \(\times\) 8 m\({}^{2}\) indoor experiment, we used the liquefied gas in the lighter to simulate real fire. When the concentration reached a threshold set by the module, the buzzer launched the alarm automatically, and the system showed the voice reminder \"fire alarm\" and sent an alarm message. Our proposed system can display the message in mobile telephone, while ICT [5] and ZigBee [9] systems are not able to do this. A screenshot of the fire alarm message is shown in Figure 4a. Figure 4b shows that our system experiences less time delay than the ZigBee and ICT systems because wireless communications, embedded technology and the sensor technology are integrated in our system. As shown in Figure 4b, we tested the system five times. In each test, our system was able to launch the fire alarm within 2 s, while the ZigBee and ICT systems have a longer time delay before they launch the fire alarm, and unstable time delay in each test.  
Figure 5 shows the application test of the system, related to the data collection of humidity and temperature modules. The system collects humidity and temperature every 3 s. With humid and hot towels (simulating a special case) near DHT11, after the temperature is higher than 30, our proposed system broadcasts the \"temperature limit alarm\" and alerts the lab administrator by calling default phone. Similarly, when the humidity is higher than 50, our proposed system broadcasts \"humidity alarm\", and alerts the lab administrator by calling default phone. When the humidity and temperature reach the upper limits (Humidity 50, Temperature 30) an alarm screenshot of our system is shown in Figure 5a, while the ZigBee and ICT systems do not have this ability. Furthermore, our system is more sensitive than the ZigBee and ICT systems. As shown in Figure 5b, we tested the system five times.  
Figure 4: Fire alarm. (**a**) Fire alarm screenshot; (**b**) Time delay.  
In each test, our system was able to launch the temperature alarm when the real temperature exceeded 30, while the ZigBee and ICT systems do not launch the temperature alarm until the real temperature exceeds 32.7. In a similar way, Figure 5c shows our system is able to launch the humidity alarm when the real humidity exceeds 50, while ZigBee and ICT systems do not launch the humidity alarm until the real humidity exceeds 53.6. The reason is that the data transmission in ZigBee and ICT systems is influenced by conditions such as transmission distance leading to message delay.  
Figure 5: Temperature and humidity alarm. (**a**) Temperature and humidity alert message; (**b**) Real temperature when alarms occur; (**c**) Real humidity when alarms occur.  
By modifying the corresponding alarm threshold, the upper limit of temperature was changed in the program. To verify the other case, we set the upper limit of the temperature to 50. After environment temperature exceeded the upper limits, the screenshot of the alarm message in our system is shown in Figure 6a. As shown in Figure 6b, in each test, our system was able to launch the temperature alarm when the real temperature exceeded 50, while the ZigBee and ICT systems do not launch the temperature alarm until the real temperature exceeds 53.3. The reason is that the data transmission is influenced by transmission distance, leading to transmission delay in the ZigBee and ICT systems.