Toby O. Davies

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This investigation developed a MATLAB program, based on genetic algorithms that generated an optimal (shortest distance) path plan for a mobile robot to visit all of the specified waypoints without colliding with the known obstacles. The designed genetic algorithm path planner was shown to accomplish this task and produce superior results when compared(More)
This paper describes a novel technique for model-based coding of 3D head and head-and-shoulders sequences. First, 3D frames are analyzed and registered using a 3D face model, fixed and known also at the decoder side. Then, shape and texture information are compressed in a lossy fashion in order to reduce spatial and temporal redundancy. Results show that(More)
We introduce a novel algorithm for temporal planning in Golog using shared resources, and describe the Bulk Freight Rail Scheduling Problem, a motivating example of such a temporal domain. We use the framework of column generation to tackle complex resource constrained temporal planning problems that are beyond the scope of current planning technology by(More)
In this paper we demonstrate the use of network analysis to characterise patterns of clustering in spatio-temporal events. Such clustering is of both theoretical and practical importance in the study of crime, and forms the basis for a number of preventative strategies. However, existing analytical methods show only that clustering is present in data, while(More)
Objectives Decades of empirical research demonstrate that crime is concentrated at a range of spatial scales, including street segments. Further, the degree of clustering at particular geographic units remains noticeably stable and consistent; a finding that Weisburd (Criminology 53:133–157, 2015) has recently termed the ‘law of crime concentration at(More)
The situation calculus can express rich agent behaviours and goals and facilitates the reduction of complex planning problems to theorem proving. However, in many planning problems, solution quality is critically important, and the achievable quality is not necessarily known in advance. Existing Golog implementations merely search for a Legal plan,(More)