Artículos con la etiqueta ‘informática’

Critical Transitions in Social Network Activity

Por • 3 ago, 2013 • Category: sociologia

A large variety of complex systems in ecology, climate science, biomedicine and engineering have been observed to exhibit tipping points, where the internal dynamical state of the system abruptly changes. For example, such critical transitions may result in the sudden change of ecological environments and climate conditions. Data and models suggest that some of these drastic events may be preceded by detectable early-warning signs. This view is also corroborated by abstract mathematical theory for generic bifurcations in stochastic multi-scale systems. Whether early-warnings are also present in social networks that anticipate \textit{a-priori unknown} events in society is an open problem to which only highly speculative answers can be given at present. Here, we focus on \textit{a-priori known} events and analyze a social network data set with a focus on classical variance and autocorrelation warning signs. We find that several a-priori known events are preceded by variance and autocorrelation growth as predicted by mathematical theory.

La informática cubana crece con recursos venezolanos

Por • 1 ago, 2013 • Category: Nacionales

El estudio publicado anualmente por el Foro Económico Mundial elabora el ranking de naciones con mayor uso de estas herramientas en sus economías. Paradójicamente, Venezuela, que es la primera compradora de los sistemas fabricados en La Habana, ocupó el puesto 108 de 144 países. La única referencia a Cuba es señalada en el aparte que detalla a las naciones con proyectos para ampliar la banda ancha.

Graph Logics with Rational Relations

Por • 27 abr, 2013 • Category: Crítica

We investigate some basic questions about the interaction of regular and rational relations on words. The primary motivation comes from the study of logics for querying graph topology, which have recently found numerous applications. Such logics use conditions on paths expressed by regular languages and relations, but they often need to be extended by rational relations such as subword or subsequence. Evaluating formulae in such extended graph logics boils down to checking nonemptiness of the intersection of rational relations with regular or recognizable relations (or, more generally, to the generalized intersection problem, asking whether some projections of a regular relation have a nonempty intersection with a given rational relation).

The Mathematician’s Bias – and the Return to Embodied Computation

Por • 22 abr, 2013 • Category: Leyes

There are growing uncertainties surrounding the classical model of computation established by G\»odel, Church, Kleene, Turing and others in the 1930s onwards. The mismatch between the Turing machine conception, and the experiences of those more practically engaged in computing, has parallels with the wider one between science and those working creatively or intuitively out in the ‘real’ world. The scientific outlook is more flexible and basic than some understand or want to admit. The science is subject to limitations which threaten careers. We look at embodiment and disembodiment of computation as the key to the mismatch, and find Turing had the right idea all along – amongst a productive confusion of ideas about computation in the real and the abstract worlds.

Numerical Simulations of the Dark Universe: State of the Art and the Next Decade

Por • 1 oct, 2012 • Category: Leyes

We present a review of the current state of the art of cosmological dark matter simulations, with particular emphasis on the implications for dark matter detection efforts and studies of dark energy. This review is intended both for particle physicists, who may find the cosmological simulation literature opaque or confusing, and for astro-physicists, who may not be familiar with the role of simulations for observational and experimental probes of dark matter and dark energy. Truly massive dark matter-only simulations are being conducted on national supercomputing centers, employing from several billion to over half a trillion particles to simulate the formation and evolution of cosmologically representative volumes (cosmic scale) or to zoom in on individual halos (cluster and galactic scale). These simulations cost millions of core-hours, require tens to hundreds of terabytes of memory, and use up to petabytes of disk storage. The field is quite internationally diverse, with top simulations having been run in China, France, Germany, Korea, Spain, and the USA. Predictions from such simulations touch on almost every aspect of dark matter and dark energy studies, and we give a comprehensive overview of this connection.

On machine creativity and the notion of free will

Por • 12 may, 2011 • Category: sociologia

We discuss the possibility of freedom of action in embodied systems that are, with no exception and at all scales of their body, subject to physical law. We relate the discussion to a model of an artificial agent that exhibits a primitive notion of creativity and freedom in dealing with its environment, which is part of a recently introduced scheme of information processing called projective simulation. This provides an explicit proposal on how we can reconcile our understanding of universal physical law with the idea that higher biological entities can acquire a notion of freedom that allows them to increasingly detach themselves from a strict causal embedding into the surrounding world.

Bases de datos de venezolanos en manos cubanas

Por • 29 mar, 2011 • Category: Nacionales

En 2005, la UCI creó lo que denomina su «cara comercial», la empresa Albet Ingeniería y Sistemas S. A., que vende los servicios y productos de la universidad cubana. «Sus resultados en la exportación la ubican como una de las principales empresas de su sector en el país, con una destacada participación en el Convenio de Cooperación Integral Cuba-Venezuela y con grandes perspectivas de crecimiento en su proyección internacional», afirma la compañía en su sitio web. De acuerdo con documentos que la UCI ha presentado en eventos internacionales, Albet esperaba facturar 174 millones de dólares en 2009 y proyecta ganancias de 252,3 millones de dólares en 2010. Las facturas se pagan con petróleo venezolano.

Superconducting Niobium Chip Smashes Silicon Power Consumption Standards

Por • 25 mar, 2011 • Category: Ciencia y tecnología

Quentin Herr and pals at Northrop Grumman Systems in Baltimore reveal a superconducting logic device that uses 300 times less power than conventional silicon chips. That’ll be a shock to chip-makers whose attempts at energy efficiency improvements pale in comparison.By comparison, the energy dissipated by the superconducting equivalent, the Josephson junction, is determined only by thermal noise, the system being entirely free of the troublesome resistance that eats up energy in conventional devices. To exploit this, Herr and co developed and built a new type of device known as a reciprocal quantum logic chip. Their superconducting chip is made of niobium, operates at 4.2 kelvin and consists of 1600 Josephson junctions .

Education for Computational Science and Engineering

Por • 25 feb, 2011 • Category: Educacion

For decades, CSE has been misunderstood to require massive computers, whereas breakthroughs in CSE have historically been the mathematical programs of computing rather than the machines themselves.

A Fight to Win the Future: Computers vs. Humans

Por • 16 feb, 2011 • Category: Ciencia y tecnología

For the past four decades that basic tension between artificial intelligence and intelligence augmentation — A.I. versus I.A. — has been at the heart of progress in computing science as the field has produced a series of ever more powerful technologies that are transforming the world.