La descentralización estructural y la heterogeneidad funcional en la producción colectiva de conocimiento: una justificación teórica y computacional del paradigma P2P

Esta tesis contiene artículos de investigación en anexo.Programa Oficial de Doctorado en Documentación: Archivos y Bibliotecas en el Entorno DigitalPresidente: Elías Sanz Casado.- Secretario: Rosario Arquero Avilés.- Vocal: Remedios Melero Meler

Modelización de Sistemas de Computación Distribuida con Bacterias Sintéticas mediante Autómatas Celulares

La conjugación es un sistema de comunicación distribuido que permite los intercambios de información genética entre bacterias. Este mecanismo peer-to-peer permite a las bacterias compartir estrategias de supervivencia implementadas en plásmidos de ADN. El presente trabajo se centra en la modelización de las dinámicas de conjugación mediante el uso de un autómata celular asíncrono y pretende servir como una aproximación formal y una herramienta de validación conceptual dentro del ámbito de la biología sintética. Este modelo se ha centrado en un caso de uso específico, una colonia heterogénea de bacterias modificadas genéticamente para discriminar plásmidos en base a la afinidad de los promotores y factores de transcripción de dos conjuntos de partida.Conjugation is a distributed communication system which allows exchanges of genetic information among bacteria. This peer-to-peer mechanism allows bacteria to share survival strategies implemented in DNA plasmids. This paper focuses on the modeling of conjugation dynamics by using asynchronous cellular automata. It intends to serve in the field of synthetic biology as a formal approach and a conceptual validation tool. This model has been focused on a specific use case, a heterogeneous colony of engineered bacteria that discriminate plasmids by evaluating affinity among pairs of promoters and transcription factors

Information literacy and peer-to-peer infrastructures: An autopoietic perspective

This article argues that an autopoietic perspective of human communities would allow to understand societies as self-organized systems and thus promote information literacy as a facilitator of social development. Peer-to-peer (P2P) social dynamics generate public information available worldwide in digital repositories, websites and bibliographic resources. However, processing such amount of data is not achievable by a single central-controlled system. We claim that distributed and heterogeneous networks of coordinated mechanisms, composed by both specialized human and artificial agents, are needed to improve information retrieval, knowledge inference and decision-making, but also to produce social value, goods and services. Handling these issues implies the collective construction of global semantic networks but also the active labor of knowledge producers and consumers. We conclude that information literacy is as much important as any technical implementation and, therefore, may lead to networks of Commons-oriented communities which would utilize P2P infrastructuresVasilis Kostakis acknowledges funding for facilities used in this research by IUT (19-13) of the Estonian Ministry of Education and Researc

Policy Analysis Tool Applied to Colombian Needs: PATACON Model Description

In this document we lay out the microeconomic foundations of a dynamic stochastic general equilibrium model designed to forecast and to advice monetary policy authorities in Colombia. The model is called Policy Analysis Tool Applied to Colombian Needs (PATACON). In companion documents we present other aspects of the model and its platform, including the estimation of the parameters that affect the dynamics and the impulse responses functions.Monetary Policy, DSGE, Small open economy. Classification JEL: E32, E52, F41.

Analysis of a chemo-repulsion model with nonlinear production: The continuous problem and unconditionally energy stable fully discrete schemes

We consider the following repulsive-productive chemotaxis model: Let $p\in (1,2)$, find $u \geq 0$, the cell density, and $v \geq 0$, the chemical concentration, satisfying \begin{equation}\label{C5:Am} \left\{ \begin{array} [c]{lll} \partial_t u - \Delta u - \nabla\cdot (u\nabla v)=0 \ \ \mbox{in}\ \Omega,\ t>0,\\ \partial_t v - \Delta v + v = u^p \ \ \mbox{in}\ \Omega,\ t>0, \end{array} \right. \end{equation} in a bounded domain $\Omega\subseteq \mathbb{R}^d$, $d=2,3$. By using a regularization technique, we prove the existence of solutions of this problem. Moreover, we propose three fully discrete Finite Element (FE) nonlinear approximations, where the first one is defined in the variables $(u,v)$, and the second and third ones by introducing ${\boldsymbol\sigma}=\nabla v$ as an auxiliary variable. We prove some unconditional properties such as mass-conservation, energy-stability and solvability of the schemes. Finally, we compare the behavior of the schemes throughout several numerical simulations and give some conclusions.Comment: arXiv admin note: substantial text overlap with arXiv:1807.0111

Evaluating a human-robot interface for exploration missions

The research reported in this paper concerns the design, implementation, and experimental evaluation of a Human-Robot Interface for stationary remote operators, implemented for a PC computer. The GUI design and functionality is described. An Autonomy Management Model has been implemented and explained. We have conducted user evaluation, making two set of experiments, that will be described and the resulting data analyzed. The conclusions give an insight on the most important usability concerns, regarding the operator situational awareness. The scalability of the interface is also experimentally studied

Monetary Policy Forecasting in a DSGE Model with Data that is Uncertain, Unbalanced and About the Future

If theory-consistent models can ever hope to forecast well and to be useful for policy, they have to relate to data which though rich in information is uncertain, unbalanced and sometimes forecasts from external sources about the future path of other variables. One example from many is financial market data, which can help but only after smoothing out irrelevant short-term volatility. In this paper we propose combining different types of useful but awkward data set with a linearised forward-looking DSGE model through a Kalman Filter fixed-interval smoother to improve the utility of these models as policy tools. We apply this scheme to a model for Colombia.Monetary Policy, DSGE, Forecast, Kalman Filter Classification JEL: F47, E01, C61.

Asimetrías del empleo y el producto, una aproximación de equilibrio general

La evidencia empírica para Colombia muestra relaciones tanto positivas como negativas entre el crecimiento del producto y empleo, a diferencia de lo encontrado en economías desarrolladas como la de los Estados Unidos. El presente trabajo usa modelos VAR y de Equilibrio General Dinámico y Estocástico para abordar explicaciones de ese fenómeno. Los resultados obtenidos, usando datos trimestrales para Colombia, son consistentes para las dos metodologías; se encuentra que la correlación entre el producto y el empleo es condicional a la fuerza motora del ciclo económico. En particular se encuentra que choques tecnológicos inducen una correlación negativa entre producto y empleo, mientras choques no tecnológicos inducen la correlación contraria.Mercado laboral, VAR estructural, DSGE, Economía abierta, Política monetaria. Classification JEL: E24, E27, E32, E37, F41, J64.

Segregation-induced grain boundary electrical potential in ionic oxide materials: A first principles model

A first principles continuum analytical model for cationic segregation to the grain boundaries in complex ceramic oxides is presented. The model permits one to determine the electric charge density and the segregation-induced electric potential profiles through the grain and can be extrapolated to the range of nanostructured grain sizes. The theoretical predictions are compared with existing data for yttria-stabilized tetragonal zirconia polycrystals. The implications for physical properties (mainly high temperature plasticity and hardening behaviour) are then discussed.Gobierno de España MAT2009-14351-C02-01, MAT2009-14351-C02-0

Modelling Complex Dynamics and Distributed Generation of Knowledge with Bacterial-Based Algorithms

This study aimed to test that connected and heterogeneous societies with peer-to-peer (P2P) exchanges are more resilient than centralized and homogeneous ones. In agent-based modeling, agents with bounded rationality interact in a common environment guided by local rules, leading to Complex Adaptive Systems that are named 'artificial societies'. These simplified models of human societies grow from the bottom up in computational environments and can be used as a laboratory to test some hypotheses. We have demonstrated that in a model based on free interactions among autonomous agents, optimal results emerge by incrementing diversity and decentralization of communication structures, as much as in real societies Internet is leading to the emergence of improvements in collective intelligence. In order to achieve a real “Knowledge Society”, what we have named a “P2P Society”, it is necessary to increase decentralization and heterogeneity through information policies, distributed communication networks, open e-learning approaches and initiatives like public domain licenses, free software and open data