8,561 research outputs found
Eerste bevindingen International Civics and Citizenship Education Study
Nederland heeft deelgenomen aan de International Civics and Citizenship Education Study (ICCS), een internationaal vergelijkend onderzoek naar burgerschapscompetenties van leerlingen in de onderbouw van het voortgezet onderwijs. Het doel van deze studie is om burgerschapscompetenties van leerlingen in verschillende landen in kaart te brengen, en na te gaan waardoor mogelijke verschillen tussen scholen en landen veroorzaakt kunnen worden
A dynamical system approach to higher order gravity
The dynamical system approach has recently acquired great importance in the
investigation on higher order theories of gravity. In this talk I review the
main results and I give brief comments on the perspectives for further
developments.Comment: 6 pages, 1 figure, 2 tables, talk given at IRGAC 2006, July 200
Role models for complex networks
We present a framework for automatically decomposing ("block-modeling") the
functional classes of agents within a complex network. These classes are
represented by the nodes of an image graph ("block model") depicting the main
patterns of connectivity and thus functional roles in the network. Using a
first principles approach, we derive a measure for the fit of a network to any
given image graph allowing objective hypothesis testing. From the properties of
an optimal fit, we derive how to find the best fitting image graph directly
from the network and present a criterion to avoid overfitting. The method can
handle both two-mode and one-mode data, directed and undirected as well as
weighted networks and allows for different types of links to be dealt with
simultaneously. It is non-parametric and computationally efficient. The
concepts of structural equivalence and modularity are found as special cases of
our approach. We apply our method to the world trade network and analyze the
roles individual countries play in the global economy
Orbital occupation, local spin and exchange interactions in V2O3
We present the results of an LDA and LDA+U band structure study of the
monoclinic and the corundum phases of V2O3 and argue that the most prominent
(spin 1/2) models used to describe the semiconductor metal transition are not
valid. Contrary to the generally accepted assumptions we find that the large on
site Coulomb and exchange interactions result in a total local spin of 1 rather
than 1/2 and especially an orbital occupation which removes the orbital
degeneracies and the freedom for orbital ordering. The calculated exchange
interaction parameters lead to a magnetic structure consistent with experiment
again without the need of orbital ordering. While the low-temperature
monoclinic distortion of the corundum crystal structure produces a very small
effect on electronic structure of v2o3, the change of magnetic order leads to
drastic differences in band widths and band gaps. The low temperature
monoclinic phase clearly favors the experimentally observed magnetic structure,
but calculations for corundum crystal structure gave two consistent sets of
exchange interaction parameters with nearly degenerate total energies
suggesting a kind of frustration in the paramagnetic phase. These results
strongly suggest that the phase transitions in V2O3 which is so often quoted as
the example of a S=1/2 Mott Hubbard system have a different origin. So back to
the drawing board
A Hierarchical Emotion Regulated Sensorimotor Model: Case Studies
Inspired by the hierarchical cognitive architecture and the perception-action
model (PAM), we propose that the internal status acts as a kind of
common-coding representation which affects, mediates and even regulates the
sensorimotor behaviours. These regulation can be depicted in the Bayesian
framework, that is why cognitive agents are able to generate behaviours with
subtle differences according to their emotion or recognize the emotion by
perception. A novel recurrent neural network called recurrent neural network
with parametric bias units (RNNPB) runs in three modes, constructing a
two-level emotion regulated learning model, was further applied to testify this
theory in two different cases.Comment: Accepted at The 5th International Conference on Data-Driven Control
and Learning Systems. 201
Newspaper clipping: Ivorey Cobb Favors Colebrook\u27s Rugged Life The Boston Sunday Globe; May 10, 1964. copy 1
A reproduction scanned from a black and white photocopy of a newspaper clipping. Article by John B. Value of the Boston Sunday Globe about Ivorey Cobb and his family and their experience in New Hampshire
Phytochemical and Biosynthetic Studies of Lignans, with a Focus on Indonesian Medicinal Plants
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