This paper establishes a relationship between reachability problems in timed automata and space-bounded counter automata. We show that reachability in timed automata with three or more clocks is naturally logarithmic-space interreducible with reachability in spacebounded counter automata with two counters. We moreover show the logarithmic-space equivalence of reachability in two-clock timed aut...

Near-infrared observations of the active galaxy MCG–6-30-15 provide strong evidence that its molecular gas fueling reservoir is of external origin. MCG–6-30-15 has a counter-rotating core of stars within its central 400 pc and a counter-rotating disc of molecular gas that extends as close as∼50–100 pc from the central black hole. The gas counter-rotation establishes that the gas reservoir in th...

Abstract: This paper establishes that when using a least squares criterion to estimate an output error type model structure, then the measurement noise induced variability of the frequency response estimate depends on the estimated (and hence also on the true) pole positions. This dependence on pole position is perhaps counter to prevailing wisdom that for any ‘shift invariant’ model structure,...

This paper establishes that when using a least squares criterion to estimate an output error type model structure, then the measurement noise induced variability of the frequency response estimate depends on the estimated (and hence also on the true) pole positions. This dependence on pole position is perhaps counter to prevailing wisdom that for any ‘shift invariant’ model structure, the varia...

Megaprojects along with creating value to the economy, create environmental, social and political disruptions in its local environment. Narratives guide action hence both promoters protesters of a project mobilize narratives advance their interest. In this process, counter-narratives are (re)created interaction often establishes dominant narrative. Using case High Speed Two (HS2) megaproject En...

This paper describes a new measure for presence in immersive virtual environments (VEs) based on data that can be obtained unobtrusively during the course of a VE experience. At different times during an experience a participant will occasionally switch between interpreting the totality of sensory inputs as forming the VE or the real world. The number of transitions from virtual to real is coun...

almost three centuries after the publication of the life and adventures of robinson crusoe, j. m. coetzee re-imagines the original story in two different versions; foe (1986) and his nobel prize acceptance speech, he and his man (2003). the recreation of one of the early novels of the western literary canon from the viewpoint of a marginalized character, which is technically called postcolonial...