Toward managing uncertain spatial information for situational awareness applications

Situational awareness (SA) applications monitor the real world and the entities therein to support tasks such as rapid decision making, reasoning, and analysis. Raw input about unfolding events may arrive from variety of sources in the form of sensor data, video streams, human observations, and so on, from which events of interest are extracted. Location is one of the most important attributes of events, useful for a variety of SA tasks. In this paper, we consider the problem of reaching situation awareness from textual input. We propose an approach to probabilistically model and represent (potentially uncertain) event locations described by human reporters in the form of free text. We analyze several types of spatial queries of interest in SA applications. We design techniques to store and index the uncertain locations, to support the efficient processing of queries. Our extensive experimental evaluation over real and synthetic data sets demonstrates the effectiveness and efficiency of our approach.