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Trajectory databases is an important research area that has received a lot of interest in the last decade. The objective of trajectory databases is to extend database technology to support the representation and querying of moving objects and their trajectory. [ABSTRACT FROM AUTHOR]

From ancient days, people have observed various moving entities, from insects and fishes to planets and stars, and investigated their movement behaviours. Although methods that were used in earlier times for observation, measurement, recording, and analysis of movements are very different from modern technologies, there is still much to learn from past studies. First, this is the thorough attention paid to the multiple aspects of movement. These include not only the trajectory (path) in space, characteristics of motion itself such as speed and direction, and their dynamics over time but also characteristics and activities of the entities that move. Second, this is the striving to relate movements to properties of their surroundings and to various phenomena and events. [ABSTRACT FROM AUTHOR]

This paper presents a semantic foundation of temporal conceptual models used to design temporal information systems. We consider a modeling language able to express both timestamping and evolution constraints. We conduct a deeper investigation on evolution constraints, eventually devising a model-theoretic semantics for a full-fledged model with both timestamping and evolution constraints. The proposed formalization is meant both to clarify the meaning of the various temporal constructors appeared in the literature and to give a rigorous definition to notions like satisfiability, subsumption and logical implication. Furthermore, we also show how to express temporal constraints using a subset of first-order temporal logic, i.e., , the description logic extended with the temporal operators Since and Until. We show how is able to capture the various modeling constraints in a succinct way and to perform automated reasoning on temporal conceptual models. [ABSTRACT FROM AUTHOR]