Indexing of network constrained moving objects

With the proliferation of mobile computing, the ability to index efficiently the movements of mobile objects becomes important. Objects are typically seen as moving in two-dimensional (x,y) space, which means that their movements across time may be embedded in the three-dimensional (x,y,t) space. Further, the movements are typically represented as trajectories, sequences of connected line segments. In certain cases, movement is restricted, and specifically in this paper, we aim at exploiting that movements occur in transportation networks to reduce the dimensionality of the data. Briefly, the idea is to reduce movements to occur in one spatial dimension. As a consequence, the movement data becomes two-dimensional (x,t). The advantages of considering such lowerdimensional trajectories are the reduced overall size of the data and the lower-dimensional indexing challenge. Since off-the-shelf database management systems typically do not offer higherdimensional indexing, this reduction in ...

• Type: Conference
• Year: 2003
• Where: GIS
• Authors: Dieter Pfoser, Christian S. Jensen
• Keywords: Database, Dimensionality-reduced Trajectories, GIS 2003, Index Trajectories, Lowerdimensional Trajectories