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We review recent relativistic hydrodynamic simulations of jets, and their interpretation in terms of the results from linear stability analysis. These studies show that, interpreted naively, the distribution of synchrotron intensity will in general be a poor guide to the physical state (density and pressure) of the underlying flow, and that even if the physical state can be inferred, it, in turn, may prove to be a poor guide to the source dynamics, in terms of the transport of energy and momentum from the central engine. However, we demonstrate that an interplay of simulation and linear stability analysis provides a powerful tool for elucidating the nature and character of structures that jets may sustain. From such studies we can explain the complex behavior of observed jets, which manifest both stationary and propagating structures, without recourse to ad hoc macroscopic disturbances. This provides a framework for the interpretation of multi-epoch total intensity data wherein an understanding of the character of individual flow features will allow the effects of physical state and dynamics to be deconvolved.
In the present paper, we investigate the cosmographic problem using the bias-variance trade-off. We find that both the z-redshift and the $y=z/(1+z)$-redshift can present a small bias estimation. It means that the cosmography can describe the superno
In astronomical and cosmological studies one often wishes to infer some properties of an infinite-dimensional field indexed within a finite-dimensional metric space given only a finite collection of noisy observational data. Bayesian inference offers
Deep convolutional neural networks learn extremely powerful image representations, yet most of that power is hidden in the millions of deep-layer parameters. What exactly do these parameters represent? Recent work has started to analyse CNN represent
This document will review the most prominent proposals using multilayer convolutional architectures. Importantly, the various components of a typical convolutional network will be discussed through a review of different approaches that base their des
Densely time sampled multi-frequency flux measurements of the extreme BL Lac object S5 0716+714 over the past three years allow us to study its broad-band variability, and the detailed underlying physics, with emphasis on the location and size of the