458 research outputs found
Algorithmic statistics, prediction and machine learning
Algorithmic statistics considers the following problem: given a binary string
(e.g., some experimental data), find a "good" explanation of this data. It
uses algorithmic information theory to define formally what is a good
explanation. In this paper we extend this framework in two directions.
First, the explanations are not only interesting in themselves but also used
for prediction: we want to know what kind of data we may reasonably expect in
similar situations (repeating the same experiment). We show that some kind of
hierarchy can be constructed both in terms of algorithmic statistics and using
the notion of a priori probability, and these two approaches turn out to be
equivalent.
Second, a more realistic approach that goes back to machine learning theory,
assumes that we have not a single data string but some set of "positive
examples" that all belong to some unknown set , a property
that we want to learn. We want this set to contain all positive examples
and to be as small and simple as possible. We show how algorithmic statistic
can be extended to cover this situation.Comment: 22 page
Case Study - IPv6 based building automation solution integration into an IPv4 Network Service Provider infrastructure
The case study presents a case study describing an Internet Protocol (IP) version 6 (v6) introduction to an IPv4 Internet Service Provider (ISP) network infrastructure. The case study driver is an ISP willing to introduce a new ākillerā service related to Internet of Things (IoT) style building automation. The provider and cooperation of third party companies specialized in building automation will provide the service. The ISP has to deliver the network access layer and to accommodate the building automation solution traffic throughout its network infrastructure. The third party companies are system integrators and building automation solution vendors. IPv6 is suitable for such solutions due to the following reasons. The operator canāt accommodate large number of IPv4 embedded devices in its current network due to the lack of address space and the fact that many of those will need clear 2 way IP communication channel.
The Authors propose a strategy for IPv6 introduction into operator infrastructure based on the current network architecture present service portfolio and several transition mechanisms. The strategy has been applied in laboratory with setup close enough to the current operatorās network. The criterion for a successful experiment is full two-way IPv6 application layer connectivity between the IPv6 server and the IPv6 Internet of Things (IoT) cloud
Destruction of Anderson localization in quantum nonlinear Schr\"odinger lattices
The four-wave interaction in quantum nonlinear Schr\"odinger lattices with
disorder is shown to destroy the Anderson localization of waves, giving rise to
unlimited spreading of the nonlinear field to large distances. Moreover, the
process is not thresholded in the quantum domain, contrary to its "classical"
counterpart, and leads to an accelerated spreading of the subdiffusive type,
with the dispersion for
. The results, presented here, shed new light on the
origin of subdiffusion in systems with a broad distribution of relaxation
times.Comment: 4 pages, no figure
L\'evy flights on a comb and the plasma staircase
We formulate the problem of confined L\'evy flight on a comb. The comb
represents a sawtooth-like potential field , with the asymmetric teeth
favoring net transport in a preferred direction. The shape effect is modeled as
a power-law dependence within the sawtooth period,
followed by an abrupt drop-off to zero, after which the initial power-law
dependence is reset. It is found that the L\'evy flights will be confined in
the sense of generalized central limit theorem if (i) the spacing between the
teeth is sufficiently broad, and (ii) , where is the fractal
dimension of the flights. In particular, for the Cauchy flights (),
. The study is motivated by recent observations of
localization-delocalization of transport avalanches in banded flows in the Tore
Supra tokamak and is intended to devise a theory basis to explain the observed
phenomenology.Comment: 13 pages; 3 figures; accepted for publication in Physical Review
Localization-delocalization transition on a separatrix system of nonlinear Schrodinger equation with disorder
Localization-delocalization transition in a discrete Anderson nonlinear
Schr\"odinger equation with disorder is shown to be a critical phenomenon
similar to a percolation transition on a disordered lattice, with the
nonlinearity parameter thought as the control parameter. In vicinity of the
critical point the spreading of the wave field is subdiffusive in the limit
. The second moment grows with time as a powerlaw , with exactly 1/3. This critical spreading finds its
significance in some connection with the general problem of transport along
separatrices of dynamical systems with many degrees of freedom and is
mathematically related with a description in terms fractional derivative
equations. Above the delocalization point, with the criticality effects
stepping aside, we find that the transport is subdiffusive with
consistently with the results from previous investigations. A threshold for
unlimited spreading is calculated exactly by mapping the transport problem on a
Cayley tree.Comment: 6 pages, 1 figur
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