Case Study  Disaster communications

identify and describe a significant advancement within the last 40 years in one of the following areas:
€¢Disaster communications.
€¢Sheltering.
€¢Evacuation.

In addition, address each of the following:
€¢What issues existed prior to the advancement you are describing?
€¢What role did past and current research play in influencing the application of this advancement in the field?
€¢What constraints existed, and how were they addressed? What constraints continue to affect this area of emergency response?