Space Time Prism

The network time prism ntp is an extension of the space time prism that provides a realistic model of the potential pattern of moving objects in transportation networks.

Space time prism. Space time prisms are a representation of where an individual may have been in between the control points of a trajectory. The space time prism concept can be used for a variety of applications. Developed as a conceptual framework in the 1960s by torsten hägerstrand analytical time geography has emerged in response to growing capabilities to collect and analyze data on mobile objects and human activities.

The broader framework wouldaddressissuessuch as the origin ofthe constraintswhich help to define the space time prism. In the 1960 70s torsten hägerstrand established what is today know as time space geography. For example if a man has to leave home at 11 00 a m.

Space time prism constructs focusing on the space time prism itself rather than the broader aspects of the time geographical framework. The reliable space time prism is defined as the set of space time locations where an individual can participate in an activity and return to his or her destination with a given on time arrival probability. Measuring the similarity among ntps can be useful for clustering aggregating and querying potential mobility patterns.

However these broader concerns are not central to the derivation and. In one of his influential papers he illustrates the spatio temporal action space of an individual through space time prisms hägerstrand 1970. A space time prism is the set of all points that can be reached by an individual given a maximum possible speed from a starting point in space time and an ending point in space time.

The space time aquarium or space time cube which displays individual paths in axonometric graphical projection of space and time coordinates. The path represents actual mobility real or simulated and the prism represents potential mobility in space with respect to time. A space time prism is the sub space an individual can reach given a speed limitation and a pair of control points.

The space time prism which shows individuals possible behavior in time space given their capability constraints and coupling constraints. A space time path represents the path taken by an individual but any one path is only one of many that can actually be taken by a person in a given amount of time. To construct such a reliable space time prism in a road network a solution algorithm is developed.