306 research outputs found

    Frequency Analysis of a 64x64 Pixel Retinomorphic System with AER Output to Estimate the Limits to Apply onto Specific Mechanical Environment

    Get PDF
    The rods and cones of a human retina are constantly sensing and transmitting the light in the form of spikes to the cortex of the brain in order to reproduce an image in the brain. Delbruck’s lab has designed and manufactured several generations of spike based image sensors that mimic the human retina. In this paper we present an exhaustive timing analysis of the Address-Event- Representation (AER) output of a 64x64 pixels silicon retinomorphic system. Two different scenarios are presented in order to achieve the maximum frequency of light changes for a pixel sensor and the maximum frequency of requested directions on the output AER. Results obtained are 100 Hz and 1.66 MHz in each case respectively. We have tested the upper spin limit and found it to be approximately 6000rpm (revolutions per minute) and in some cases with high light contrast lost events do not exist.Ministerio de Ciencia e Innovación TEC2009-10639- C04-0

    Science, Technology, and Innovation Governance for Social Inclusion and Sustainable Development in Latin America

    Get PDF
    The introduction of the concept of governance in Latin America belongs to the neoliberal policies of privatization that tried to trace and assure that public funds, especially international loans, can overcome several corruption problems and the lag in the bargaining between public and private actors. The idea that transparency and accountability in the private actors that receive contracts from the States with the slogan of competitiveness reach bankruptcy. In this framework, studies in science, technology, and innovation (STI) began to interest in governance as a way to explain how policy and research networks create space, mechanisms, and instruments to negotiate and steer policies and actions and create a better future. The scientific challenges to solve complex problems need several actors and fields beyond traditional ministries and bureaucratic governments jurisdictions. Then, governance arises to understand the coordination between several stakeholders that are able to collaborate and develop systems to achieve common goals. This chapter introduces the book that covers the research shared in the congress “Governance of science, technology, and innovation for inclusive and sustainable development in Latin America” organized by the Network on Governance and Management of Science, Technology, and Innovation—(Red GCTI) with a critical point of view. The main contribution is to show the topics, approaches, controversies, trends, and challenges in the Latin American research of STI governance for social inclusion and sustainability

    Construyendo la Web de las Cosas: Ahorro energético y gestión de iluminación en ciudades

    Get PDF
    Se están realizando muchos esfuerzos para acercar aquellos objetos de la vida cotidiana a Internet. A lo largo de estos últimos años han emergido una gran cantidad de tecnologías como comunicación por proximidad -RFID o NFC-, localización en tiempo real o sensores embebidos. Además la computación distribuida, las tecnologías móviles y la conectividad en cualquier lugar están cobrando una mayor relevancia. La unión de todo esto nos permite transformar objetos de cada día en objetos inteligentes que pueden entender y reaccionar ante su entorno.En este artículo vamos a presentar como llevar toda esta tecnología a la vida real. Vamos a describir cómo implantar dispositivos en farolas y cómo hemos realizado diversos demostradores, de forma que se ha controlado, regulado y monitorizado remotamente su consumo energético. A lo largo del trabajo describiremos las pautas a seguir para llevar estas propuestas a nuestras ciudades

    Performance Study of Software AER-Based Convolutions on a Parallel Supercomputer

    Get PDF
    This paper is based on the simulation of a convolution model for bioinspired neuromorphic systems using the Address-Event-Representation (AER) philosophy and implemented in the supercomputer CRS of the University of Cadiz (UCA). In this work we improve the runtime of the simulation, by dividing an image into smaller parts before AER convolution and running each operation in a node of the cluster. This research involves a test cases design in which the optimal parameters are set to run the AER convolution in parallel processors. These cases consist on running the convolution taking an image divided in different number of parts, applying to each part a Sobel filter for edge detection, and based on the AER-TOOL simulator. Execution times are compared for all cases and the optimal configuration of the system is discussed. In general, CRS obtain better performances when the image is divided than for the whole image.Ministerio de Ciencia e Innovación TEC2009-10639-C04-0

    Entropy and equilibrium state of free market models

    Full text link
    Many recent models of trade dynamics use the simple idea of wealth exchanges among economic agents in order to obtain a stable or equilibrium distribution of wealth among the agents. In particular, a plain analogy compares the wealth in a society with the energy in a physical system, and the trade between agents to the energy exchange between molecules during collisions. In physical systems, the energy exchange among molecules leads to a state of equipartition of the energy and to an equilibrium situation where the entropy is a maximum. On the other hand, in the majority of exchange models, the system converges to a very unequal condensed state, where one or a few agents concentrate all the wealth of the society while the wide majority of agents shares zero or almost zero fraction of the wealth. So, in those economic systems a minimum entropy state is attained. We propose here an analytical model where we investigate the effects of a particular class of economic exchanges that minimize the entropy. By solving the model we discuss the conditions that can drive the system to a state of minimum entropy, as well as the mechanisms to recover a kind of equipartition of wealth

    Serum proteomics of active tuberculosis patients and contacts reveals unique processes activated during Mycobacterium tuberculosis infection.

    Get PDF
    Tuberculosis (TB) is the most lethal infection among infectious diseases. The specific aim of this study was to establish panels of serum protein biomarkers representative of active TB patients and their household contacts who were either infected (LTBI) or uninfected (EMI-TB Discovery Cohort, Pontevedra Region, Spain). A TMT (Tamdem mass tags) 10plex-based quantitative proteomics study was performed in quintuplicate containing a total of 15 individual serum samples per group. Peptides were analyzed in an LC-Orbitrap Elite platform, and raw data were processed using Proteome Discoverer 2.1. A total of 418 proteins were quantified. The specific protein signature of active TB patients was characterized by an accumulation of proteins related to complement activation, inflammation and modulation of immune response and also by a decrease of a small subset of proteins, including apolipoprotein A and serotransferrin, indicating the importance of lipid transport and iron assimilation in the progression of the disease. This signature was verified by the targeted measurement of selected candidates in a second cohort (EMI-TB Verification Cohort, Maputo Region, Mozambique) by ELISA and nephelometry techniques. These findings will aid our understanding of the complex metabolic processes associated with TB progression from LTBI to active disease

    Pareto and Boltzmann-Gibbs behaviors in a deterministic multi-agent system

    Full text link
    A deterministic system of interacting agents is considered as a model for economic dynamics. The dynamics of the system is described by a coupled map lattice with near neighbor interactions. The evolution of each agent results from the competition between two factors: the agent's own tendency to grow and the environmental influence that moderates this growth. Depending on the values of the parameters that control these factors, the system can display Pareto or Boltzmann-Gibbs statistical behaviors in its asymptotic dynamical regime. The regions where these behaviors appear are calculated on the space of parameters of the system. Other statistical properties, such as the mean wealth, the standard deviation, and the Gini coefficient characterizing the degree of equity in the wealth distribution are also calculated on the space of parameters of the system.Comment: 9 pages, 9 color .eps figures, submitted to Physica

    RSME 2011. Transfer and Industrial Mathematics. Proceedings of the RSME Conference on Transfer and Industrial Mathematics. Santiago de Compostela, July 12-14, 2011

    Get PDF
    [EN] The RSME Conference on Transfer and Industrial Mathematics is supported by the Royal Spanish Mathematical Society, a scientific society for the promotion of mathematics and its applications as well as the encouragement of research and teaching at all educational levels. The three-day conference presents successful experiences in the field of mathematical knowledge transfer to industry and focuses on the following issues: — Showing how collaboration with industry has opened up new lines of research in the field of mathematics providing high quality contributions to international journals and encouraging the development of doctoral theses. — How the promotion of existing infrastructures has contributed to enhance the transfer of mathematical knowledge to industry. — The presentation of postgraduate programs offering training in mathematics with industrial applications. The conference includes talks from researchers and industry representatives who present their different points of view and experiences with regards to the transfer of mathematical knowledge to industry

    The use of physical restraints in long-term care in Spain: a multi-center cross-sectional study

    Get PDF
    Background Physical restraint is a procedure used frequently in long-term care. It is a controversial practice because its use is associated with numerous complications and also affects freedom and individual autonomy. The objective of this study was to examine the use of physical restraint of long-term care residents with the ability to move voluntarily. Methods We conducted a cross-sectional observational and correlational multi-center study. Nine centers agreed to participate. Of the 1,200 people present at the time of data collection, those without voluntary movement or in the facility for less than a month were excluded. Thus, the final sample was 920 residents. Data on the use of restraints was collected by direct observation. Information about the age, gender, length of stay, falls, mobility, cognition and functional status of residents was gathered by reviewing clinical records and interviewing nursing staff. A descriptive analysis of the data obtained was conducted. The generalized linear model was used, considering only the principal effects of each variable and using the logit link function. The model has been adjusted for clusters and for other possibly confounding factors. For all analyses, a confidence interval (CI) of 95% was estimated. Results The prevalence of residents with at least one physical restraint was 84.9% (95% CI: 81.7–88.1), with variability between centers of 70.3 to 96.6% (p-value Kruskal Wallis test <0.001). Full-enclosure side rails were most often used (84.5; 95% CI: 81.1–87.9), but other types of restraints were also used frequently. Multivariate analysis showed that the degree of functional impairment increased the probability of the use of restraint. A significant association was also found between restraint use and the impaired cognitive status of residents. Conclusions The prevalence was higher than in studies from other countries. The results emphasize the need to improve the training of nursing staff in the care of residents with impairments in functional and cognitive status. The use of alternative devices and nurse consultants need to be evaluated, and the introduction of specific laws considered.Sociedad Canaria de Geriatría y Gerontología and the Fundación Canaria de Investigación Sanitaria financed this study.S
    corecore