6,026 research outputs found
Development and Evolution of Neural Networks in an Artificial Chemistry
We present a model of decentralized growth for Artificial Neural Networks
(ANNs) inspired by the development and the physiology of real nervous systems.
In this model, each individual artificial neuron is an autonomous unit whose
behavior is determined only by the genetic information it harbors and local
concentrations of substrates modeled by a simple artificial chemistry. Gene
expression is manifested as axon and dendrite growth, cell division and
differentiation, substrate production and cell stimulation. We demonstrate the
model's power with a hand-written genome that leads to the growth of a simple
network which performs classical conditioning. To evolve more complex
structures, we implemented a platform-independent, asynchronous, distributed
Genetic Algorithm (GA) that allows users to participate in evolutionary
experiments via the World Wide Web.Comment: 8 pages LaTeX, style file included, 8 embedded postscript figures. To
be published in Proc. of 3rd German Workshop on Artificial Life (GWAL
Evoplex: A platform for agent-based modeling on networks
Agent-based modeling and network science have been used extensively to
advance our understanding of emergent collective behavior in systems that are
composed of a large number of simple interacting individuals or agents. With
the increasing availability of high computational power in affordable personal
computers, dedicated efforts to develop multi-threaded, scalable and
easy-to-use software for agent-based simulations are needed more than ever.
Evoplex meets this need by providing a fast, robust and extensible platform for
developing agent-based models and multi-agent systems on networks. Each agent
is represented as a node and interacts with its neighbors, as defined by the
network structure. Evoplex is ideal for modeling complex systems, for example
in evolutionary game theory and computational social science. In Evoplex, the
models are not coupled to the execution parameters or the visualization tools,
and there is a user-friendly graphical interface which makes it easy for all
users, ranging from newcomers to experienced, to create, analyze, replicate and
reproduce the experiments.Comment: 6 pages, 5 figures; accepted for publication in SoftwareX [software
available at https://evoplex.org
WebAL Comes of Age: A review of the first 21 years of Artificial Life on the Web
We present a survey of the first 21 years of web-based artificial life (WebAL) research and applications, broadly construed to include the many different ways in which artificial life and web technologies might intersect. Our survey covers the period from 1994—when the first WebAL work appeared—up to the present day, together with a brief discussion of relevant precursors. We examine recent projects, from 2010–2015, in greater detail in order to highlight the current state of the art. We follow the survey with a discussion of common themes and methodologies that can be observed in recent work and identify a number of likely directions for future work in this exciting area
Tools of the Trade: A Survey of Various Agent Based Modeling Platforms
Agent Based Modeling (ABM) toolkits are as diverse as the community of people who use them. With so many toolkits available, the choice of which one is best suited for a project is left to word of mouth, past experiences in using particular toolkits and toolkit publicity. This is especially troublesome for projects that require specialization. Rather than using toolkits that are the most publicized but are designed for general projects, using this paper, one will be able to choose a toolkit that already exists and that may be built especially for one's particular domain and specialized needs. In this paper, we examine the entire continuum of agent based toolkits. We characterize each based on 5 important characteristics users consider when choosing a toolkit, and then we categorize the characteristics into user-friendly taxonomies that aid in rapid indexing and easy reference.Agent Based Modeling, Individual Based Model, Multi Agent Systems
The GalMer database: Galaxy Mergers in the Virtual Observatory
We present the GalMer database, a library of galaxy merger simulations, made
available to users through tools compatible with the Virtual Observatory (VO)
standards adapted specially for this theoretical database. To investigate the
physics of galaxy formation through hierarchical merging, it is necessary to
simulate galaxy interactions varying a large number of parameters:
morphological types, mass ratios, orbital configurations, etc. On one side,
these simulations have to be run in a cosmological context, able to provide a
large number of galaxy pairs, with boundary conditions given by the large-scale
simulations, on the other side the resolution has to be high enough at galaxy
scales, to provide realistic physics. The GalMer database is a library of
thousands simulations of galaxy mergers at moderate spatial resolution and it
is a compromise between the diversity of initial conditions and the details of
underlying physics. We provide all coordinates and data of simulated particles
in FITS binary tables. The main advantages of the database are VO access
interfaces and value-added services which allow users to compare the results of
the simulations directly to observations: stellar population modelling, dust
extinction, spectra, images, visualisation using dedicated VO tools. The GalMer
value-added services can be used as virtual telescope producing broadband
images, 1D spectra, 3D spectral datacubes, thus making our database oriented
towards the usage by observers. We present several examples of the GalMer
database scientific usage obtained from the analysis of simulations and
modelling their stellar population properties, including: (1) studies of the
star formation efficiency in interactions; (2) creation of old counter-rotating
components; (3) reshaping metallicity profiles in elliptical galaxies; (4)
orbital to internal angular momentum transfer; (5) reproducing observed colour
bimodality of galaxies.Comment: 15 pages, 11 figures, 10 tables accepted to A&A. Visualisation of
GalMer simulations, access to snapshot files and value-added tools described
in the paper are available at http://galmer.obspm.fr
The Hierarchic treatment of marine ecological information from spatial networks of benthic platforms
Measuring biodiversity simultaneously in different locations, at different temporal scales, and over wide spatial scales is of strategic importance for the improvement of our understanding of the functioning of marine ecosystems and for the conservation of their biodiversity. Monitoring networks of cabled observatories, along with other docked autonomous systems (e.g., Remotely Operated Vehicles [ROVs], Autonomous Underwater Vehicles [AUVs], and crawlers), are being conceived and established at a spatial scale capable of tracking energy fluxes across benthic and pelagic compartments, as well as across geographic ecotones. At the same time, optoacoustic imaging is sustaining an unprecedented expansion in marine ecological monitoring, enabling the acquisition of new biological and environmental data at an appropriate spatiotemporal scale. At this stage, one of the main problems for an effective application of these technologies is the processing, storage, and treatment of the acquired complex ecological information. Here, we provide a conceptual overview on the technological developments in the multiparametric generation, storage, and automated hierarchic treatment of biological and environmental information required to capture the spatiotemporal complexity of a marine ecosystem. In doing so, we present a pipeline of ecological data acquisition and processing in different steps and prone to automation. We also give an example of population biomass, community richness and biodiversity data computation (as indicators for ecosystem functionality) with an Internet Operated Vehicle (a mobile crawler). Finally, we discuss the software requirements for that automated data processing at the level of cyber-infrastructures with sensor calibration and control, data banking, and ingestion into large data portals.Peer ReviewedPostprint (published version
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