Hechen Liu

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—Moving objects in the physical world usually generate many uncertain trajectories for some reasons such as the consideration of energy consumption, leaving the route passing two consecutive sampling points unknown. While such trajectories imply rich knowledge about the mobility of moving objects, they are less useful individually. This paper introduces an(More)
A moving region whose location and extend change over time can imply topological changes such as <i>region split</i> and <i>hole formation</i>. To study this phenomenon is useful in many applications, e.g. the topology control of wireless sensor networks and emergency handling. It is challenging to detect the topological changes of a moving region since we(More)
Recently, a wide range of applications like hurricane research, fire management, navigation systems, and transportation has shown increasing interest in managing and analyzing space and time-referenced objects, so-called <i>moving objects</i>, that continuously change their positions over time. In the same way as moving objects can change their location(More)
Spatio-temporal uncertainty is a special feature of moving objects due to the inability of precisely capturing or predicting their continuously changing locations. Indeterminate locations of moving objects at time instants add uncertainty to their topological relationships. Spatio-temporal uncertainty is important in many applications, for example , to(More)
Many geographical applications need to model spatial phenomena with vague or indeterminate boundaries and interiors. A popular paradigm adopted by the GIS community for this task at the modeling level is fuzzy set theory. A spatial object is fuzzy if locations exist that cannot be assigned completely to the object or to its complement. In previous work, we(More)
In the same way as moving objects can change their location over time, the spatial relationships between them can change over time. An important class of spatial relationships are cardinal directions like north and southeast. In spatial databases and GIS, they characterize the relative directional position between static objects in space and are frequently(More)
The spatio-temporal uncertainty is an inherent feature of moving objects. One scenario where uncertainty exists is the movement of moving objects in the future, which results from lacking the knowledge of the prediction method. To solve this problem is useful, for example, to predict the locations of a hurricane and its relationships with points of interest(More)
AbstrAct: Exploring the topology of a region object requires the mathematical study of its geometric properties that are preserved under deformations. A moving region whose location and extent change over time can undergo several topo-logical changes such as the splitting of a region or the formation of a hole. The study of this kind of changes is important(More)
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