5,088 research outputs found
Simulating Spiking Neural P systems without delays using GPUs
We present in this paper our work regarding simulating a type of P system
known as a spiking neural P system (SNP system) using graphics processing units
(GPUs). GPUs, because of their architectural optimization for parallel
computations, are well-suited for highly parallelizable problems. Due to the
advent of general purpose GPU computing in recent years, GPUs are not limited
to graphics and video processing alone, but include computationally intensive
scientific and mathematical applications as well. Moreover P systems, including
SNP systems, are inherently and maximally parallel computing models whose
inspirations are taken from the functioning and dynamics of a living cell. In
particular, SNP systems try to give a modest but formal representation of a
special type of cell known as the neuron and their interactions with one
another. The nature of SNP systems allowed their representation as matrices,
which is a crucial step in simulating them on highly parallel devices such as
GPUs. The highly parallel nature of SNP systems necessitate the use of hardware
intended for parallel computations. The simulation algorithms, design
considerations, and implementation are presented. Finally, simulation results,
observations, and analyses using an SNP system that generates all numbers in
- {1} are discussed, as well as recommendations for future work.Comment: 19 pages in total, 4 figures, listings/algorithms, submitted at the
9th Brainstorming Week in Membrane Computing, University of Seville, Spai
Incompressible surfaces in handlebodies and boundary reducible 3-manifolds
We study the existence of incompressible embeddings of surfaces into the
genus two handlebody. We show that for every compact surface with boundary,
orientable or not, there is an incompressible embedding of the surface into the
genus two handlebody. In the orientable case the embedding can be either
separating or non-separating. We also consider the case in which the genus two
handlebody is replaced by an orientable 3-manifold with a compressible boundary
component of genus greater than or equal to two.Comment: 33 pages, 14 figure
An Improved GPU Simulator For Spiking Neural P Systems
Spiking Neural P (SNP) systems, variants of Psystems (under Membrane and Natural computing), are computing models that acquire abstraction and inspiration from the way neurons 'compute' or process information. Similar to other P system variants, SNP systems are Turing complete models that by nature compute non-deterministically and in a maximally parallel manner. P systems usually trade (often exponential) space for (polynomial to constant) time. Due to this nature, P system variants are currently limited to parallel simulations, and several variants have already been simulated in parallel devices. In this paper we present an improved SNP system simulator based on graphics processing units (GPUs). Among other reasons, current GPUs are architectured for massively parallel computations, thus making GPUs very suitable for SNP system simulation. The computing model, hardware/software considerations, and simulation algorithm are presented, as well as the comparisons of the CPU only and CPU-GPU based simulators.Ministerio de Ciencia e Innovación TIN2009–13192Junta de Andalucía P08-TIC-0420
Detecting Invasive Insects with Unmanned Aerial Vehicles
A key aspect to controlling and reducing the effects invasive insect species
have on agriculture is to obtain knowledge about the migration patterns of
these species. Current state-of-the-art methods of studying these migration
patterns involve a mark-release-recapture technique, in which insects are
released after being marked and researchers attempt to recapture them later.
However, this approach involves a human researcher manually searching for these
insects in large fields and results in very low recapture rates. In this paper,
we propose an automated system for detecting released insects using an unmanned
aerial vehicle. This system utilizes ultraviolet lighting technology, digital
cameras, and lightweight computer vision algorithms to more quickly and
accurately detect insects compared to the current state of the art. The
efficiency and accuracy that this system provides will allow for a more
comprehensive understanding of invasive insect species migration patterns. Our
experimental results demonstrate that our system can detect real target insects
in field conditions with high precision and recall rates.Comment: IEEE ICRA 2019. 7 page
Experimental evidence for a surface distribution of two-level systems in superconducting lithographed microwave resonators
We present measurements of the temperature-dependent frequency shift of five
niobium superconducting coplanar waveguide microresonators with center strip
widths ranging from 3 m to 50 m, taken at temperatures in the range
100-800 mK, far below the 9.2 K transition temperature of niobium. These data
agree well with the two-level system (TLS) theory. Fits to this theory provide
information on the number of TLS that interact with each resonator geometry.
The geometrical scaling indicates a surface distribution of TLS, and the data
are consistent with a TLS surface layer thickness of order a few nm, as might
be expected for a native oxide layer.Comment: 3 figures, submitted to AP
Augmented reality mobile application to promote e-Tourism of the architectural cultural heritage of Historic Center of Santa Anar
Este artículo presenta el resultado del proyecto de investigación aplicada ejecutado por las carreras de Técnico en Ingeniería
de Sistemas Informáticos y Técnico en Gestión Tecnológica del Patrimonio Cultural de la Escuela Especializada en Ingeniería
ITCA-FEPADE Centro Regional Santa Ana. El proyecto tuvo como objetivo principal promover el e-Turismo y difundir la riqueza
de las estructuras arquitectónicas con valor patrimonial del Centro Histórico de la ciudad de Santa Ana. Con este propósito se
desarrolló la aplicación ARquitec Santa Ana para dispositivos móviles. Esta App de realidad aumentada está disponible para la
plataforma Android en sus versiones 7.0 Nougat (API 24) y posteriores, publicada en la Google Play Store y con acceso gratuito.
La aplicación permite visualizar e interactuar con modelos 3D de los edificios más importantes y emblemáticos del Centro
Histórico de Santa Ana y contiene además una reseña en formato de texto y fotografías de los mismos edificios. Los edificios
recreados dentro de la App son: Catedral de Santa Ana, Teatro de Santa Ana, Palacio Municipal de Santa Ana, Centro de Arte
de Occidente y Casa Ex Escalón. La aplicación es una herramienta útil para promover y divulgar la riqueza arquitectónica a
través de modelos virtuales y contribuye a la comprensión y puesta en valor de las edificaciones y monumentos del Centro
Histórico de Santa Ana. La App pueda ser utilizada en entornos virtuales de aprendizaje, convirtiéndose en un recurso
didáctico alternativo para la comprensión y valoración del patrimonio cultural dentro del aula
Eficiencia de tres métodos de muestreo para estimar poblaciones de broca del café (Hypothenemus hampei Ferrari Coleoptera: Curculionidae) en el ciclo 2007-2008 en dos zonas cafetaleras de Nicaragua
Con el objetivo de estudiar la eficiencia de tres métodos de muestreo de broca del café (Hypothenemus hampeiFerr), se realizó la presente investigación en fincas cafetaleras ubicadas en las zonas cafetaleras de San Ramón, Matagalpa y en El Crucero, Managua durante el ciclo 2007 - 2008 Los métodos de muestreo que se utilizaron fueron: Recuento de frutos brocados, disección de frutos brocados y trampeo de adultos. Los muestreos se realizaron mensualmente. Las variables evaluadas fueron:
porcentaje de frutos brocados, número de adultos, número de larvas, número de pupas, numero de huevos, total (adultos, larvas, pupas, huevos) de estados biológicos por fruto disectado y número de adultos por trampa. A los datos obtenidos del porcentaje de frutos brocados y número de adultos por trampa se les realizó un ANDEVA y separación de medias por Tukey. También se realizó una correlación entre los datos obtenidos en cada fecha de muestreo en los tres métodos de muestreo. Los tres métodos de muestreo reflejan que la infestación de broca es significativamente mayor en la zona de Matagalpa con promedio de 15.8% que en la de Managua con promedio de 0.7%. El mayor porcentaje de frutos brocados se presentó en el mes de Diciembre. En época seca las capturas de adultos en trampas fueron mayores en comparación con la época lluviosa. Los mayores promedios larvas, pupas y adultos fueron encontrados en el mes de Noviembre, en
cambio el mayor promedio de huevos se encontró en el mes de Diciembre. El resultado de la correlación indicó la existencia de una asociación positiva solo entre los métodos de muestreo de frutos brocados y disección de frutos con un r = 0.59. Los mayores promedios de estados
inmaduros y adultos por frutos fueron encontrados en la finca Santa Emilia, presentando un comportamiento ascendente durante el periodo de desarrollo y maduración del fruto. Se determinó que el muestreo visual de frutos
brocados es el método más eficiente para la estimación de niveles de infestación de H. hampei en el cultivo de café
Laboratory Simulation of the Effect of Rocket Thrust on a Precessing Space Vehicle
Ground tests of solid propellant rocket motors have shown that metal-containing propellants produce various amounts of slag (primarily aluminum oxide) which is trapped in the motor case, causing a loss of specific impulse. Although not yet definitely established, the presence of a liquid pool of slag also may contribute to nutational instabilities that have been observed with certain spin-stabilized, upper-stage vehicles. Because of the rocket's axial acceleration, absent in the ground tests, estimates of in-flight slag mass have been very uncertain. Yet such estimates are needed to determine the magnitude of the control authority of the systems required for eliminating the instability. A test rig with an eccentrically mounted hemispherical bowl was designed and built which incorporates a follower force that properly aligns the thrust vector along the axis of spin. A program that computes the motion of a point mass in the spinning and precessing bowl was written. Using various RPMs, friction factors, and initial starting conditions, plots were generated showing the trace of the point mass around the inside of the fuel tank. The apparatus will incorporate future design features such as a variable nutation angle and a film height measuring instrument. Data obtained on the nutational instability characteristics will be used to determine order of magnitude estimates of control authority needed to minimize the sloshing effect
The goose that laid the golden eggs? Agricultural development in Latin America in the 20th century
In the last third of the nineteenth century, a large majority of Latin America adopted export-led models of growth, mostly based on agricultural exports. In some countries, this strategy produced significant results in terms of economic development but in most of the countries, the strategy was not successful, either because of too slow growth in exports or because linkages with the rest of the economy were very weak and there was no significant growth-spreading effect. After WWII, Latin America turned to a new model of economic development: the import substitution industrialisation (ISI). The ISI policies penalised export-led agriculture. The 1980s and 1990s were characterised by an expansion of adjustment policies and structural reforms. The new strategy consisted of mobilising resources in competitive export sectors, including agriculture.En el último tercio del siglo XIX, la gran mayoría de los países de Latinoamérica adoptaron modelos de crecimiento dirigidos por las exportaciones, principalmente basados en exportaciones agrarias. En algunos países, esta estrategia dio resultados importantes en términos de desarrollo económico, pero en la mayoría no fue exitosa, bien porque tuvieron un crecimiento demasiado lento de sus exportaciones o porque los efectos de arrastre hacia el resto de la economía fueron muy débiles y no hubo por lo tanto un impulso importante hacia el desarrollo. Después de la Segunda Guerra Mundial, Latinoamérica viró hacia un nuevo modelo de desarrollo económico: la industrialización sustitutiva de importaciones (ISI). Las políticas ISI penalizaron a la agricultura de exportación. Las décadas de los ochenta y noventa estuvieron caracterizadas por una generalización de políticas de ajuste y reforma estructural. La nueva estrategia consistió en movilizar recursos en los sectores exportadores competitivos, incluyendo entre estos a la agricultura
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