## 3 Active Disaster Response System (ADRS)
### Prototype of ADRS and Use Scenarios  
Figure 10 shows the prototype of ADRS, which consists of three parts of the Tibbo development kit. They are the input/output control lines and the Wi-Fi SPI module. Tibbo boards are used to receive warning messages published by the Central Weather Bureau and parse the XML-based format CAP messages to extract disaster information. In addition, a Wi-Fi SPI module is adopted so as to provide a wireless network function to Tibbo, which can also collect household members' messages. These messages are stored in the flash memory. Because a user can connect to a Tibbo in one hop to post  
Figure 9: The relationship between ADRS and a crowdsourcing-enhanced emergency management system. emergency messages, he or she, if trapped, will be found in the transmission range of one hop, which is around 20 to 30 m. The last part of ADRS is the input/output control lines, which are used to control relay switches, so that home devices can be turned on or off and opened or closed. In our prototype, Tibbo can control alerts, doors, power, gas, _etc._, or even use Wi-Fi wireless networks to control devices, like personal computers, to save important data. We installed ADRS in the smart home demo room (EB208) in the CSIE (Computer Science and Information Engineering) department at National Yunlin University of Science and Technology, Taiwan. Figure 11 shows a CAP message containing an earthquake alert delivered by the PubNub service. After receiving the warning message, ADRS converts it to a human readable version for people in the building (shown in Figure 12) and performs associated emergency tasks. Please note that ADRS should go through a rigorous testing before it can be deployed. In order to address the issue of power failure, in our prototype, the ADRS connects to a UPS (uninterruptible power supply) that provides emergency power when the input power source fails. In addition, the electric door lock we adopted can be unlocked by remote (_i.e._, ADRS) or by hand. When the unlock button of the electric door is pressed, the power of the control circuit is cut, so that the remote cannot prevent the door from being opened. We note that ADRS, in addition to earthquakes, can process alerts for other types of disasters and be extended to respond to them in and out of buildings. For example, when landslides and debris flows happen, ADRS can trigger message signs put up before tunnels and bridges to warn drivers to slow down and pull over. For flash floods, ADRS can change the traffic light to red, so that the roads can be closed. It also can turn on pumps to extract floodwater or start automatic flood barriers, to save low-lying buildings from rising water levels. For tornados, ADRS can automatically open the outside doors and vents to equalize air pressure inside and outside of a house, preventing it from exploding and also unlock each shelter door to minimize the chance of such a tragedy. For volcanic eruptions, ADRS can cooperate with microcontrollers to close all windows and doors to protect people from volcanic ash. ADRS should be able to deal with false negatives, which are false alarms due to system errors. Because CAP messages are also posted on authenticated websites, such as NCDR in Taiwan [26], we can adopt a two-way communication to avoid false alarms induced by system software errors. ADRS, before performing emergency tasks, should use the hyperlink in the alert segment of the received CAP message to connect to the authenticated website and search for the same CAP message. If the same CAP message cannot be found, ADRS should cancel the emergency tasks to avoid false alarms. Figure 12: Human readable version. In addition, performing routine maintenance on the hardware devices is also needed to avoid possible false alarms caused by system hardware errors. ADRS also should be able to deal with false negatives when the system fails to respond. Among the solutions, one of the practical ways is to use an external watchdog timer to detect the status of ADRS.