Spontaneous structure formation in a network of chaotic units with variable connection strengths

As a model of temporally evolving networks, we consider a globally coupled logistic map with variable connection weights. The model exhibits self-organization of network structure, reflected by the collective behavior of units. Structural order emerges even without any inter-unit synchronization of dynamics. Within this structure, units spontaneously separate into two groups whose distinguishing feature is that the first group possesses many outwardly-directed connections to the second group, while the second group possesses only few outwardly-directed connections to the first. The relevance of the results to structure formation in neural networks is briefly discussed.Comment: 4 pages, 3 figures, REVTe

A Survey on Continuous Time Computations

We provide an overview of theories of continuous time computation. These theories allow us to understand both the hardness of questions related to continuous time dynamical systems and the computational power of continuous time analog models. We survey the existing models, summarizing results, and point to relevant references in the literature

Time-Dependent Density Functional Theory for Driven Lattice Gas Systems with Interactions

We present a new method to describe the kinetics of driven lattice gases with particle-particle interactions beyond hard-core exclusions. The method is based on the time-dependent density functional theory for lattice systems and allows one to set up closed evolution equations for mean site occupation numbers in a systematic manner. Application of the method to a totally asymmetric site exclusion process with nearest-neighbor interactions yields predictions for the current-density relation in the bulk, the phase diagram of non-equilibrium steady states and the time evolution of density profiles that are in good agreement with results from kinetic Monte Carlo simulations.Comment: 11 pages, 3 figure

AMBIGÜEDAD E INCERTIDUMBRE EN DESARROLLO SUSTENTABLE (DS)Y TURISMO SUSTENTABLE (TS): SUS IMPLICACIONES EPISTEMOLÓGICAS

Muchas implicaciones epistemológicas del DS y TS permanecen ocultas. Para intentar descubrirlas, se revisan y analizan los supuestos y argumentos utilizados en su conceptualización, operacionalización y evaluación. Dos grandes temas no siempre explícitos, pero subyacentes en la literatura sirven para este propósito: ambigüedad e incertidumbre. Se concluye que es en el último eslabón de la cadena teoría o planteamiento/operacionalización, donde se produce el aspecto crucial: la intervención, y que puede haber una sola incertidumbre, la de cómo nos articulamos con los sistemas complejos en que nos encontramos

Supervised Learning in Multilayer Spiking Neural Networks

The current article introduces a supervised learning algorithm for multilayer spiking neural networks. The algorithm presented here overcomes some limitations of existing learning algorithms as it can be applied to neurons firing multiple spikes and it can in principle be applied to any linearisable neuron model. The algorithm is applied successfully to various benchmarks, such as the XOR problem and the Iris data set, as well as complex classifications problems. The simulations also show the flexibility of this supervised learning algorithm which permits different encodings of the spike timing patterns, including precise spike trains encoding.Comment: 38 pages, 4 figure

Suppression of forest fuel thermal decomposition under the influence of liquid aerosol and water droplets with additives

This article presents findings of experimental research into suppressing the thermal decomposition of forest fuel (birch leaves, spruce needles, kindling wood and mixed forest fuel) under conditions of exposure water aerosol and single water droplets, as well as water with specialized additives. We used typical model of fire source with fixed height 0.04 m and varied diameter 0.02-0.1m. Water spraying process, as well as interaction between water and forest fuel was registered using highspeed video camera (recording frequency 6∙105 fps) and panoramic optical methods ("Particle Image Velocimetry", "Shadow Photography"). We established principles of water additions' influence on termination of combustion and thermal decomposition of fire source model

La escala en el Desarrollo Sustentable (DS) y Turismo Sustentable (TS): sus implicaciones epistemológicas

Muchos aspectos y problemáticas epistemológicas del DS y TS se concentran en la escala, incluyendo los relacionados con ambigüedad e incertidumbre (en otro documento), al mismo tiempo de indicar fuertes cuestionamientos a las formas actuales de generación de conocimiento. Esta situación responde, tanto a la emergencia de fenómenos inéditos en la literatura científica, como a las nuevas perspectivas científicas que conducen al derrumbe de supuestos anteriores. De este modo, los problemas de la escala nos indican las limitaciones de sus acepciones usuales; la resistencia que van poniendo los objetos de estudio complejos a esas limitaciones, y la necesidad de definir formas organizacionales o conceptos alternativos al de escala, para tratar con concepciones holísticas