In modern emergency responses, computer-aided dispatch (CAD) systems play a critical role in rescue unit management. Currently, majority of CAD systems that used by emergency departments around the world could provider three major functionalities for emergency operators, which are (1) sending dispatch orders to rescue units; (2) recording the information of emergency incidents and dispatched units into databases and (3) tracking dispatched rescue units [5, 9]. Although using CAD systems could simplify the management of rescue units, emergency operators still need to manually select appropriate units and deploy them for emergency incidents. According to our analysis of the open database of San Francisco Fire Department , the time used for the unit dispatch of an emergency incident usually occupy 35% to 45% of the total unit deployment time, which is a time-consuming process for life-threatening incidents such as house fires or vehicle accidents. Besides, with the rapid growth of emergency service demands in metropolitan regions [2, 3], emergency operators might need to simultaneously handle the emergency responses of multiple incidents with different severities, contents and rescue unit requirements.