Search results for "computer"

A study of (im)politeness on the Facebook pages of the main Spanish political parties: the gender variable and face acts

2019

Este estudio pretende conocer qué sexo tiene mayor participación en las páginas de Facebook de los 5 principales partidos políticos españoles: Partido Socialista Obrero Español (PSOE), Partido Popular (PP), Ciudadanos, Unidos Podemos y Vox y si el comportamiento en función del sexo difiere en torno a los actos de refuerzo de la imagen (FFA - face flattering acts) y a los actos de ataque a la imagen (FTA - face threatening acts). Para ello, se ha elaborado un análisis métrico de la campaña electoral de las elecciones generales del año 2019 y se ha recogido un corpus de 2500 comentarios durante el último día, el 26 de abril.

Reinforcement learning approach to nonequilibrium quantum thermodynamics

2021

We use a reinforcement learning approach to reduce entropy production in a closed quantum system brought out of equilibrium. Our strategy makes use of an external control Hamiltonian and a policy gradient technique. Our approach bears no dependence on the quantitative tool chosen to characterize the degree of thermodynamic irreversibility induced by the dynamical process being considered, require little knowledge of the dynamics itself and does not need the tracking of the quantum state of the system during the evolution, thus embodying an experimentally non-demanding approach to the control of non-equilibrium quantum thermodynamics. We successfully apply our methods to the case of single- …

MoMo: enabling hybrid museums

2005

Present-day museums are not mere passive institutions for the preservation of a society's cultural heritage. They have become instead learning environments, research centres and even tourist attractions. The paper introduces the notion of a hybrid museum (HM) in which wireless personal digital devices (PDAs) are used to tailor digital contents to the visitor to enrich both the learning and entertainment experience. The paper describes a fully functional hybrid museum infrastructure (MoMo) implemented with the.NET compact framework running on the PocketPC platform. Several research challenges that had to be faced during the implementation of the system such as the exploration of large sets o…

The transition state and cognate concepts

2019

Abstract This review aims firstly to clarify the meanings of key terms and concepts associated with the idea of the transition state, as developed by theoreticians and applied by experimentalist, and secondly to provide an update to the meaning and significance of the transition state in an era when computational simulation, in which complexity is being increasingly incorporated, is commonly employed as a means by which to bridge the realms of theory and experiment. The relationship between the transition state and the potential-energy surface for an elementary reaction is explored, with discussion of the following terms: saddle point, minimum-energy reaction path, reaction coordinate, acti…

Variable time amplitude amplification and quantum algorithms for linear algebra problems

2012

Quantum amplitude amplification is a method of increasing a success probability of an algorithm from a small epsilon>0 to Theta(1) with less repetitions than classically. In this paper, we generalize quantum amplitude amplification to the case when parts of the algorithm that is being amplified stop at different times. We then apply the new variable time amplitude amplification to give two new quantum algorithms for linear algebra problems. Our first algorithm is an improvement of Harrow et al. algorithm for solving systems of linear equations. We improve the running time of the algorithm from O(k^2 log N) to O(k log^3 k log N) where k is the condition number of the system of equations. …

Computer Science Meets Ecology (Dagstuhl Seminar 17091)

2017

This report summarizes the program and main outcomes of the Dagstuhl Seminar 17091 entitled ``Computer Science Meets Ecolog''. Ecology is a discipline that poses many challenging problems involving big data collection, provenance and integration, as well as difficulties in data analysis, prediction and understanding. All these issues are precisely the arena where computer science is concerned. The seminar motivation was rooted in the belief that ecology could largely benefit from modern computer science. The seminar attracted scientists from both fields who discussed important topics in ecology (e.g. botany, animal science, biogeochemistry) and how to approach them with machine learning, co…

FO^2 with one transitive relation is decidable

2013

We show that the satisfiability problem for the two-variable first-order logic, FO^2, over transitive structures when only one relation is required to be transitive, is decidable. The result is optimal, as FO^2 over structures with two transitive relations, or with one transitive and one equivalence relation, are known to be undecidable, so in fact, our result completes the classification of FO^2-logics over transitive structures with respect to decidability. We show that the satisfiability problem is in 2-NExpTime. Decidability of the finite satisfiability problem remains open.

NightShift: NMR shift inference by general hybrid model training - a framework for NMR chemical shift prediction

2013

Abstracts from the CECAM workshop on computer simulations of cellular automata

1989

Efficient generation of restricted growth words

2013

A length n restricted growth word is a word w=w"1w"2...w"n over the set of integers where w"1=0 and each w"i, i>1, lies between 0 and the value of a word statistics of the prefix w"1w"2...w"i"-"1 of w, plus one. Restricted growth words simultaneously generalize combinatorial objects as restricted growth functions, staircase words and ascent or binary sequences. Here we give a generic generating algorithm for restricted growth words. It produces a Gray code and runs in constant average time provided that the corresponding statistics has some local properties.