Search results for "SPACE"
showing 10 items of 21658 documents
The Exponential Dichotomy under Discretization on General Approximation Scheme
2011
This paper is devoted to the numerical analysis of abstract parabolic problem š¢ ī ( š” ) = š“ š¢ ( š” ) ; š¢ ( 0 ) = š¢ 0 , with hyperbolic generator š“ . We are developing a general approach to establish a discrete dichotomy in a very general setting in case of discrete approximation in space and time. It is a well-known fact that the phase space in the neighborhood of the hyperbolic equilibrium can be split in a such way that the original initial value problem is reduced to initial value problems with exponential decaying solutions in opposite time direction. We use the theory of compact approximation principle and collectively condensing approximation to show that such a decomposition oā¦
RTS2 - the Remote Telescope System
2010
RTS2 is an open source observatory manager. It was written from scratch in the C++ language, with portability and modularity in mind. Its driving requirements originated from quick follow-ups of Gamma Ray Bursts. After some years of development it is now used to carry tasks it was originally not intended to carry. This article presents the current development status of the RTS2 code. It focuses on describing strategies which worked as well as things which failed to deliver expected results. Copyright Ā© 2010 Petr KubĆ”nek.
Fuzzy C-Means Segmentation on Brain MR Slices Corrupted by RF-Inhomogeneity
2007
Brain MR Images corrupted by RF-Inhomogeneity exhibit brightness variations in such a way that a standard Fuzzy C-Means (fcm) segmentation algorithm fails. As a consequence, modified versions of the algorithm can be found in literature, which take into account the artifact. In this work we show that the application of a suitable pre-processing algorithm, already presented by the authors, followed by a standard fcm segmentation achieves good results also. The experimental results ones are compared with those obtained using SPM5, which can be considered the state of the art algorithm oriented to brain segmentation and bias removal.
Categorically algebraic topology versus universal topology
2013
This paper continues to develop the theory of categorically algebraic (catalg) topology, introduced as a common framework for the majority of the existing many-valued topological settings, to provide convenient means of interaction between different approaches. Motivated by the results of universal topology of H. Herrlich, we show that a concrete category is fibre-small and topological if and only if it is concretely isomorphic to a subcategory of a category of catalg topological structures, which is definable by topological co-axioms.
A spiking network for body size learning inspired by the fruit fly
2013
The concept of peripersonal space is an interesting research topics for psychologists, neurobiologists and for robotic applications. A living being can learn the representation of its own body to take the correct behavioral decision when interacting with the world. To transfer these important learning mechanisms on bio-robots, simple and efficient solutions can be found in the insect world. In this paper a neural-based model for body-size learning is proposed taking into account the results obtained in experiments with fruit flies. Simulations and experimental results on a roving platform are reported and compared with the biological counterpart.
Estimation of Granger causality through Artificial Neural Networks: applications to physiological systems and chaotic electronic oscillators
2021
One of the most challenging problems in the study of complex dynamical systems is to find the statistical interdependencies among the system components. Granger causality (GC) represents one of the most employed approaches, based on modeling the system dynamics with a linear vector autoregressive (VAR) model and on evaluating the information flow between two processes in terms of prediction error variances. In its most advanced setting, GC analysis is performed through a state-space (SS) representation of the VAR model that allows to compute both conditional and unconditional forms of GC by solving only one regression problem. While this problem is typically solved through Ordinary Least Sqā¦
Topological systems and Artin glueing
2012
Abstract Using methods of categorical fuzzy topology, the paper shows a relation between topological systems of S. Vickers and Artin glueing of M. Artin. Inspired by the problem of interrelations between algebra and topology, we show the necessary and sufficient conditions for the category, obtained by Artin glueing along an adjoint functor, to be (co)algebraic and (co)monadic, incorporating the respective result of G. Wraith. As a result, we confirm the algebraic nature of the category of topological systems, showing that it is monadic.
Diverging Collectives: Artist-Run Spaces versus Warehouse Shows Comparative models of art production and cooperation among young British artists
2017
The paper addresses the case of artist-run spaces and warehouse shows in the United Kingdom between the 1980s and 1990s, a time when autonomous group shows and independent artist collectives sprawled particularly thanks to the engagement of a new generation of artists, among whom were found later celebrities such as Damien Hirst and Douglas Gordon. It will be argued that both artist-run spaces and warehouse shows were feasible solutions for young authors against art market barriers and economic crisis, although they held structural and organisational differences that would affect aesthetic outcomes and present art history with a shift in the model of the art collective.
Internal Simulation of an Agentās Intentions
2013
We present the Associative Self-Organizing Map (A-SOM) and propose that it could be used to predict an agentās intentions by internally simulating the behaviour likely to follow initial movements. The A-SOM is a neural network that develops a representation of its input space without supervision, while simultaneously learning to associate its activity with an arbitrary number of additional (possibly delayed) inputs. We argue that the A-SOM would be suitable for the prediction of the likely continuation of the perceived behaviour of an agent by learning to associate activity patterns over time, and thus a way to read its intentions.
ZvaigžÅotÄ Debess: 2009, Rudens (205)
2009
Contents: I.Daube. JÄnis Ikaunieks ; A.Balklavs. Mountains on the Venus ; TASS and āPravdaā materials. Soviet Automatic Stations āVenera-5ā and āVenera-6ā Reach Venus ; A.Alksnis. Gathering of Astronomers at the University ; A.Alksnis, M.Äbele, I.EglÄ«tis, B.Rjabovs, K.SalmiÅÅ”, I.Pundure. Directions of Scientific Research of the UL Institute of Astronomy Assessed ; D.Docenko. Meteorite Fallen in Sudan Recovered ; A.Alksnis. How Asteroids Will Disturb Observation with Extremely Large Telescopes ; M.Gills. Daily in Network with Astronomy ; I.Pundure. Arturs Balklavs and Astronomy of Latvia (continued) ; M.SudÄrs. IXV ā Step towards Reusable Space Vehicles ; V.KalniÅÅ”. Hyperdrive and Heimās Quaā¦