1,230 research outputs found

    Hyperuniformity and Number Rigidity of Inflation Tilings

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    In this article we prove that a large class of inflation tilings are hyperuniform: this includes the novel hat tilings introduced by Smith et al. and well known examples such as Penrose, Ammann-Beenker and shield tilings. In some cases, such as for Penrose tilings, we are also able to prove number rigidity, making them the first aperiodic examples with finite local complexity, hyperuniformity and number rigidity in higher dimensions. We prove this by deriving self-similarity equations for spherical diffraction, which generalize renormalization relations for ordinary diffraction found by Baake and Grimm. Our method applies to inflation tilings of arbitrary dimensions for which there is a sufficiently large eigenvalue gap in the reduced substitution matri

    Crowd simulation in an emergency situation

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    Los planes de evacuación de diferentes edificios, barcos y cualquier otro tipo de sitios públicos es difícil de definir, al menos, si quieres que sea lo más eficiente, seguro y rápido posible. El proyecto trata de simular un espacio virtual con avatares ficticios y un usuario que intentarán salir.The evacuation plan for different buildings, ships and all kind of public spaces is hard to define, at least, if you want it to be the most efficient plan, thus the safest and the fastest. Therefore, the project is about simulating an environment with virtual avatars trying to find the way out

    Emergent behaviors in the Internet of things: The ultimate ultra-large-scale system

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    To reach its potential, the Internet of Things (IoT) must break down the silos that limit applications' interoperability and hinder their manageability. Doing so leads to the building of ultra-large-scale systems (ULSS) in several areas, including autonomous vehicles, smart cities, and smart grids. The scope of ULSS is both large and complex. Thus, the authors propose Hierarchical Emergent Behaviors (HEB), a paradigm that builds on the concepts of emergent behavior and hierarchical organization. Rather than explicitly programming all possible decisions in the vast space of ULSS scenarios, HEB relies on the emergent behaviors induced by local rules at each level of the hierarchy. The authors discuss the modifications to classical IoT architectures required by HEB, as well as the new challenges. They also illustrate the HEB concepts in reference to autonomous vehicles. This use case paves the way to the discussion of new lines of research.Damian Roca work was supported by a Doctoral Scholarship provided by Fundación La Caixa. This work has been supported by the Spanish Government (Severo Ochoa grants SEV2015-0493) and by the Spanish Ministry of Science and Innovation (contracts TIN2015-65316-P).Peer ReviewedPostprint (author's final draft

    Rendimiento académico de la nueva propuesta metodológica europea (Bolonia) para la docencia de la Publicidad i Relaciones Públicas: Creatividad y diseño

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    Universidad Autónoma de Barcelona, Facultad de Ciencias de la Comunicación, Departamento de Comunicación Audiovisual y Publicidad, Grupo de Recerca en Publicitat. España

    Performance Bounds for Finite Moving Average Change Detection: Application to Global Navigation Satellite Systems

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    Due to the widespread deployment of Global Navigation Satellite Systems (GNSSs) for critical road or urban applications, one of the major challenges to be solved is the provision of integrity to terrestrial environments, so that GNSS may be safety used in these applications. To do so, the integrity of the received GNSS signal must be analyzed in order to detect some local effect disturbing the received signal. This is desirable because the presence of some local effect may cause large position errors, and hence compromise the signal integrity. Moreover, the detection of such disturbing effects must be done before some pre-established delay. This kind of detection lies within the field of transient change detection. In this work, a finite moving average stopping time is proposed in order to approach the signal integrity problem with a transient change detection framework. The statistical performance of this stopping time is investigated and compared, in the context of multipath detection, to other different methods available in the literature. Numerical results are presented in order to assess their performance.Comment: 12 pages, 2 figures, transaction paper, IEEE Transaction on Signal Processing, 201

    Streakline-based closed-loop control of a bluff body flow

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    A novel closed-loop control methodology is introduced to stabilize a cylinder wake flow based on images of streaklines. Passive scalar tracers are injected upstream the cylinder and their concentration is monitored downstream at certain image sectors of the wake. An AutoRegressive with eXogenous inputs mathematical model is built from these images and a Generalized Predictive Controller algorithm is used to compute the actuation required to stabilize the wake by adding momentum tangentially to the cylinder wall through plasma actuators. The methodology is new and has real-world applications. It is demonstrated on a numerical simulation and the provided results show that good performances are achieved.Fil: Roca, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Ingeniería Mecánica. Laboratorio de Fluidodinámica; ArgentinaFil: Cammilleri, Ada. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Ingeniería Mecánica. Laboratorio de Fluidodinámica; ArgentinaFil: Duriez, Thomas Pierre Cornil. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Ingeniería Mecánica. Laboratorio de Fluidodinámica; ArgentinaFil: Mathelin, Lionel. Centre National de la Recherche Scientifique. Laboratoire d'Informatique pour la Mécanique et les Sciences de l'Ingénieur; FranciaFil: Artana, Guillermo Osvaldo. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Ingeniería Mecánica. Laboratorio de Fluidodinámica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Ab initio determination of the electron affinities of DNA and RNA nucleobases

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    High-level quantum-chemical ab initio coupled-cluster and multiconfigurational perturbation methods have been used to compute the vertical and adiabatic electron affinities of the five canonical DNA and RNA nucleobases: uracil, thymine, cytosine, adenine, and guanine. The present results aim for the accurate determination of the intrinsic electron acceptor properties of the isolated nucleic acid bases as described by their electron affinities, establishing an overall set of theoretical reference values at a level not reported before and helping to rule out less reliable theoretical and experimental data and to calibrate theoretical [email protected] [email protected] [email protected] [email protected]

    Training-induced gene expression plasticity in cardiac function and neural regulation for ultra-trail runners

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    This study aims to assess the gene regulatory response from a group of 16 athletes and to observe the plasticity induced by their training regime on the gene expression response after their participation in an 82km race. Blood samples for differential gene expression (DGE) were collected before and after this effort from two groups of runners with different training regimes: elite and active. Analyses only focused on genes annotated as related to cardiac function (CF) and neural regulation (NR) from the KEGG PATHWAY Database. Thus, 13 pathways were considered accounting for a total of 629 genes. Training regime modulated the response to exercise based on a list of 18 ranked genes with significant DGE for elite runners while remained statistically insignificant for active athletes. UQCR11, COX7C and COX4I1 genes, related to mitochondrial respiratory chain, were down-regulated which may indicate mitochondrial function impairment in cardiac muscle. Increased expression levels were obtained for PIK3R2, PLCG2, IRAK3 genes from the positive signaling cascades of neurotrophins pathway, which may reveal an improved heart rate control thanks to a better cardiac sympathetic innervation.Postprint (author's final draft

    Bootstrap Causality Tests Of The Relationship Between The Equity Markets Of The US And Other Developed Countries: Pre- And Post-September 11

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    We analyse the causal relationship between the equity markets of the US and those of the UK, Japan, Germany, France, Canada and Australia based on leveraged bootstrap approach developed by Hacker and Hatemi-J (2005). This method overcomes problems of non-normalities and ARCH effects in the data. Using weekly MSCI price indices, we focus our investigation on the period 1998 to 2005 which we divided into two sub-periods to take into account the potential structural break arising from September 11. Our results show that before September 11, there was bi-directional causality between the US and Japan and between the US and Germany. In addition, there was also a uni-directional causality from the US to Canada and from the US to France. After September 11, the only causality was a unidirectional one from the US to Japan and from the UK to the US. Thus, after September 11, the US Granger-caused a fewer number of markets. This could imply that after September 11, the other markets became more efficient in responding to information transmitted from the US market

    Should large Spanish municipalities be financially compensated? Costs and benefits of being a capital/central municipality

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    We determine the costs and benefits of being a capital or central municipality, where central costs are understood to be incurred specifically as a result of the problems large municipalities located at the centre of an urban agglomeration face (including costs associated with social issues, immigration, commuting and diseconomies of scale) and capital costs result from the presence of regional and/or central government institutions in the municipality (loss of revenue or increase in expenditure because of activity substitution). However, these two qualities might also be beneficial to municipalities (resulting in a direct increase in their revenue or fiscal capacity). By estimating an equation of the expenditure needs and the fiscal capacity of Spanish municipalities with more than 75,000 inhabitants, we find that the central costs incurred by large municipalities are offset by their greater fiscal capacity, but that the same is not true for municipalities that serve as political/administrative capitals
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