11,029 research outputs found
Undefining Man: A Case for Symbolic Animal Communication via Refutation of Kenneth Burke\u27s Definition of Man
There have been tendencies in various fields to use communication as a way of differentiating humans and other species. Even when individuals are confronted with empirical evidence to the contrary, many still hold onto the notion that humans are in a communicative position clearly divergent in all ways from animals. This thesis will utilize Kenneth Burke\u27s Definition of Man as a launching point to support a claim that animals utilize their conscious cognitive abilities to communicate symbolically
A system of mobile agents to model social networks
We propose a model of mobile agents to construct social networks, based on a
system of moving particles by keeping track of the collisions during their
permanence in the system. We reproduce not only the degree distribution,
clustering coefficient and shortest path length of a large data base of
empirical friendship networks recently collected, but also some features
related with their community structure. The model is completely characterized
by the collision rate and above a critical collision rate we find the emergence
of a giant cluster in the universality class of two-dimensional percolation.
Moreover, we propose possible schemes to reproduce other networks of particular
social contacts, namely sexual contacts.Comment: Phys. Rev. Lett. (in press
Ammattikoulutusta Kelan kuntoutuksena vuonna 2003 saaneiden työ- ja eläketilanteen rekisteriseuranta vuosina 2003-2006
Atomic Diffusion and Mixing in Old Stars. III. Analysis of NGC 6397 Stars under New Constraints
We have previously reported on chemical abundance trends with evolutionary
state in the globular cluster NGC 6397 discovered in analyses of spectra taken
with FLAMES at the VLT. Here, we reinvestigate the FLAMES-UVES sample of 18
stars, ranging from just above the turnoff point (TOP) to the red giant branch
below the bump. Inspired by new calibrations of the infrared flux method, we
adopt a set of hotter temperature scales. Chemical abundances are determined
for six elements (Li, Mg, Ca, Ti, Cr, and Fe). Signatures of cluster-internal
pollution are identified and corrected for in the analysis of Mg.
On the modified temperature scales, evolutionary trends in the abundances of
Mg and Fe are found to be significant at the 2{\sigma} and 3{\sigma} levels,
respectively. The detailed evolution of abundances for all six elements agrees
with theoretical isochrones, calculated with effects of atomic diffusion and a
weak to moderately strong efficiency of turbulent mixing. The age of these
models is compatible with the external determination from the white dwarf
cooling sequence. We find that the abundance analysis cannot be reconciled with
the strong turbulent-mixing efficiency inferred elsewhere for halo field stars.
A weak mixing efficiency reproduces observations best, indicating a
diffusion-corrected primordial lithium abundance of log {\epsilon}(Li) = 2.57
+- 0.10. At 1.2{\sigma}, this value agrees well with WMAP-calibrated Big-Bang
nucleosynthesis predictions.Comment: 14 pages, 5 figures, accepted by Ap
Kelan mielenterveyskuntoutuksessa olleiden lasten ja nuorten psyykenlääkkeiden käyttö ja kuntoutuminen : Rekisteriselvitys vuosilta 2000-2006
Model of mobile agents for sexual interactions networks
We present a novel model to simulate real social networks of complex
interactions, based in a granular system of colliding particles (agents). The
network is build by keeping track of the collisions and evolves in time with
correlations which emerge due to the mobility of the agents. Therefore,
statistical features are a consequence only of local collisions among its
individual agents. Agent dynamics is realized by an event-driven algorithm of
collisions where energy is gained as opposed to granular systems which have
dissipation. The model reproduces empirical data from networks of sexual
interactions, not previously obtained with other approaches.Comment: 6 pages, 8 figure
On a Wing and a Prayer? Challenges for Reducing Armed Violence
Most deaths due to violence now occur outside traditional conflict settings. In these contexts, violence is complex and often hard to understand, linked to a variety of conditions, situations and trends which are deeply embedded and difficult to shift without considerable investment, contextual knowledge and risk. Development is indispensible to reducing armed violence, while aid efforts are expected to be informed by rigorous evidence and qualify as good value for money. Therefore, defining and determining success in this field is urgently needed. This policy briefing explores the challenges of generating better evidence as well as how to respond to complexity, proposing where efforts should be focused.UK Department for International Developmen
The dune size distribution and scaling relations of barchan dune fields
Barchan dunes emerge as a collective phenomena involving the generation of
thousands of them in so called barchan dune fields. By measuring the size and
position of dunes in Moroccan barchan dune fields, we find that these dunes
tend to distribute uniformly in space and follow an unique size distribution
function. We introduce an analyticalmean-field approach to show that this
empirical size distribution emerges from the interplay of dune collisions and
sand flux balance, the two simplest mechanisms for size selection. The
analytical model also predicts a scaling relation between the fundamental
macroscopic properties characterizing a dune field, namely the inter-dune
spacing and the first and second moments of the dune size distribution.Comment: 6 pages, 4 figures. Submitted for publicatio
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