6,661 research outputs found
An investigation of the hidden structure of states in a mean field spin glass model
We study the geometrical structure of the states in the low temperature phase
of a mean field model for generalized spin glasses, the p-spin spherical model.
This structure cannot be revealed by the standard methods, mainly due to the
presence of an exponentially high number of states, each one having a vanishing
weight in the thermodynamic limit. Performing a purely entropic computation,
based on the TAP equations for this model, we define a constrained complexity
which gives the overlap distribution of the states. We find that this
distribution is continuous, non-random and highly dependent on the energy range
of the considered states. Furthermore, we show which is the geometrical shape
of the threshold landscape, giving some insight into the role played by
threshold states in the dynamical behaviour of the system.Comment: 18 pages, 8 PostScript figures, plain Te
The emergence of active perception - seeking conceptual foundations
The aim of this thesis is to explain the emergence of active perception. It takes an interdisciplinary approach, by providing the necessary conceptual foundations for active perception research - the key notions that bridge the conceptual gaps remaining in understanding emergent behaviours of active perception in the context of robotic implementations. On the one hand, the autonomous agent approach to mobile robotics claims that perception is active. On the other hand, while explanations of emergence have been extensively pursued in Artificial Life, these explanations have not yet successfully accounted for active perception.The main question dealt with in this thesis is how active perception systems, as behaviour -based autonomous systems, are capable of providing relatively optimal perceptual guidance in response to environmental challenges, which are somewhat unpredictable. The answer is: task -level emergence on grounds of complicatedly combined computational strategies, but this notion needs further explanation.To study the computational strategies undertaken in active perception re- search, the thesis surveys twelve implementations. On the basis of the surveyed implementations, discussions in this thesis show that the perceptual task executed in support of bodily actions does not arise from the intentionality of a homuncu- lus, but is identified automatically on the basis of the dynamic small mod- ules of particular robotic architectures. The identified tasks are accomplished by quasi -functional modules and quasi- action modules, which maintain transformations of perceptual inputs, compute critical variables, and provide guidance of sensory -motor movements to the most relevant positions for fetching further needed information. Given the nature of these modules, active perception emerges in a different fashion from the global behaviour seen in other autonomous agent research.The quasi- functional modules and quasi- action modules cooperate by estimating the internal cohesion of various sources of information in support of the envisaged task. Specifically, such modules basically reflect various computational facilities for a species to single out the most important characteristics of its ecological niche. These facilities help to achieve internal cohesion, by maintaining a stepwise evaluation over the previously computed information, the required task, and the most relevant features presented in the environment.Apart from the above exposition of active perception, the process of task - level emergence is understood with certain principles extracted from four models of life origin. First, the fundamental structure of active perception is identified as the stepwise computation. Second, stepwise computation is promoted from baseline to elaborate patterns, i.e. from a simple system to a combinatory system. Third, a core requirement for all stepwise computational processes is the comparison between collected and needed information in order to insure the contribution to the required task. Interestingly, this point indicates that active perception has an inherent pragmatist dimension.The understanding of emergence in the present thesis goes beyond the distinc- tion between external processes and internal representations, which some current philosophers argue is required to explain emergence. The additional factors are links of various knowledge sources, in which the role of conceptual foundations is two -fold. On the one hand, those conceptual foundations elucidate how various knowledge sources can be linked. On the other, they make possible an interdisci- plinary view of emergence. Given this two -fold role, this thesis shows the unity of task -level emergence. Thus, the thesis demonstrates a cooperation between sci- ence and philosophy for the purpose of understanding the integrity of emergent cognitive phenomena
Individual growth in competence
This article presents the second study in a series that has been designed to manifest the emergence of consciousness and to measure developed competence. Its major aim has been to demonstrate that an invariant formulation of the Agent-action-Objective model and an analysis of its A-O kinematics have the capacity to re-produce contour similarity over time. Within the studied evolutionary-developmental context, the bio-kinematics of the discove¬red AaO-mechanism has governed the synthesising of information. It has been possible to demonstrate variations in growth as changes in complexity. When the two participating students are compared, differences in their perspectivation, and consequently in their attractor spaces, become apparent. Based on coordinated structural invariants, it has been possible to show that the convoluted spaces of the student, who has followed the analytic-descriptive approach, is concerned with the concrete level of the tested story. On the other hand, the student, who is following a synthetic-reflective strategy, seems to concentrate mainly on the symbolic level. Thus, from the developmental point of view, it has been possible to demonstrate that the AaO-mechanism is tracing embodied growth, which becomes manifest in the differences of the students’ ability to adapt to the main idea of the given story
Proceedings of the second "international Traveling Workshop on Interactions between Sparse models and Technology" (iTWIST'14)
The implicit objective of the biennial "international - Traveling Workshop on
Interactions between Sparse models and Technology" (iTWIST) is to foster
collaboration between international scientific teams by disseminating ideas
through both specific oral/poster presentations and free discussions. For its
second edition, the iTWIST workshop took place in the medieval and picturesque
town of Namur in Belgium, from Wednesday August 27th till Friday August 29th,
2014. The workshop was conveniently located in "The Arsenal" building within
walking distance of both hotels and town center. iTWIST'14 has gathered about
70 international participants and has featured 9 invited talks, 10 oral
presentations, and 14 posters on the following themes, all related to the
theory, application and generalization of the "sparsity paradigm":
Sparsity-driven data sensing and processing; Union of low dimensional
subspaces; Beyond linear and convex inverse problem; Matrix/manifold/graph
sensing/processing; Blind inverse problems and dictionary learning; Sparsity
and computational neuroscience; Information theory, geometry and randomness;
Complexity/accuracy tradeoffs in numerical methods; Sparsity? What's next?;
Sparse machine learning and inference.Comment: 69 pages, 24 extended abstracts, iTWIST'14 website:
http://sites.google.com/site/itwist1
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