A survey on deep learning in image polarity detection: Balancing generalization performances and computational costs

Deep convolutional neural networks (CNNs) provide an effective tool to extract complex information from images. In the area of image polarity detection, CNNs are customarily utilized in combination with transfer learning techniques to tackle a major problem: the unavailability of large sets of labeled data. Thus, polarity predictors in general exploit a pre-trained CNN as the feature extractor that in turn feeds a classification unit. While the latter unit is trained from scratch, the pre-trained CNN is subject to fine-tuning. As a result, the specific CNN architecture employed as the feature extractor strongly affects the overall performance of the model. This paper analyses state-of-the-art literature on image polarity detection and identifies the most reliable CNN architectures. Moreover, the paper provides an experimental protocol that should allow assessing the role played by the baseline architecture in the polarity detection task. Performance is evaluated in terms of both generalization abilities and computational complexity. The latter attribute becomes critical as polarity predictors, in the era of social networks, might need to be updated within hours or even minutes. In this regard, the paper gives practical hints on the advantages and disadvantages of the examined architectures both in terms of generalization and computational cost

La valoración de las noticias políticas en la agenda mediática: una propuesta metodológica para el análisis de contenido

La ponderación del tono valorativo de las noticias ha sido una preocupación recurrente para diferentes perspectivas teóricas del campo de la comunicación política. Entre ellas, la teoría de la Agenda Setting se ha destacado por abordar esta dimensión de análisis en múltiples trabajos en contextos electorales y no electorales. Sin embargo, en la mayoría de esos estudios se han replicado las categorías “positivo”, “neutro” y “negativo” para operacionalizar el concepto de tono valorativo, sin que las mismas fueran definidas exhaustivamente. A partir de un análisis de contenido cuantitativo de las piezas periodísticas publicadas por los diarios argentinos Clarín, La Nación y Página/12 sobre el conflicto desatado en 2008 entre el gobierno de la Presidenta Cristina Fernández y las principales corporaciones agropecuarias del país, a raíz de la decisión del Poder Ejecutivo de elevar los derechos de exportación sobre las principales materias primas que produce el sector, el presente estudio tiene por objetivo general construir un índice de valoración compuesto por diferentes variables complementarias: la valoración del acontecimiento principal de la nota, la valoración de los actores y la valoración del rol del Estado referido en cada pieza. La aplicación de la herramienta metodológica sobre el corpus descripto arrojó como resultado la predominancia de piezas con un tono valorativo negativo. No obstante, el análisis desagregado del comportamiento de cada una de las variables del índice permitió vislumbrar evaluaciones diferentes de los acontecimientos, los actores y las políticas públicas en cada diario, concordantes con sus líneas editoriales

A Comprehensive Framework for the Security Risk Management of Cyber-Physical Systems

Cyber Physical Systems are facing huge and diverse set of security risks, especially cyber-attacks that can cause disruption to physical services or create a national disaster. Information and communication technology (ICT) has made a remarkable impact on the society. A Cyber Physical System (CPS) relies basically on information and communication technology, which puts the system\u2019s assets under certain risks especially cyber ones, and hence they must be kept under control by means of security countermeasures that generate confidence in the use of these assets. And so there is a critical need to give a great attention on the cybersecurity of these systems, which consequently leads to the safety of the physical world. This goal is achieved by adopting a solution that applies processes, plans and actions to prevent or reduce the effects of threats. Traditional IT risk assessment methods can do the job, however, and because of the characteristics of a CPS, it is more efficient to adopt a solution that is wider than a method, and addresses the type, functionalities and complexity of a CPS. This chapter proposes a framework that breaks the restriction to a traditional risk assessment method and encompasses wider set of procedures to achieve a high level strategy that could be adopted in the risk management process, in particular the cybersecurity of cyber-physical systems

Complexity-Entropy Causality Plane as a Complexity Measure for Two-dimensional Patterns

Complexity measures are essential to understand complex systems and there are numerous definitions to analyze one-dimensional data. However, extensions of these approaches to two or higher-dimensional data, such as images, are much less common. Here, we reduce this gap by applying the ideas of the permutation entropy combined with a relative entropic index. We build up a numerical procedure that can be easily implemented to evaluate the complexity of two or higher-dimensional patterns. We work out this method in different scenarios where numerical experiments and empirical data were taken into account. Specifically, we have applied the method to i) fractal landscapes generated numerically where we compare our measures with the Hurst exponent; ii) liquid crystal textures where nematic-isotropic-nematic phase transitions were properly identified; iii) 12 characteristic textures of liquid crystals where the different values show that the method can distinguish different phases; iv) and Ising surfaces where our method identified the critical temperature and also proved to be stable.Comment: Accepted for publication in PLoS On

A high-resolution aeromagnetic survey over the Cape Roberts Rift Basin: Correlations with seismic reflection and magnetic susceptibility log data

A high-resolution aeromagnetic survey (altitude 125 m asl, spacing 500 m , area 800 km2) was carried out in 1994 offshore of Cape Roberts by the GITARA (German ITalian Aeromagnetic Research in Antarctica) Group. The availability from drilling of whole-core physical properties logs for magnetic susceptibility, P-wave velocity and density/porosity data allows new insights to be inferred from reprocessed and reviewed HRAM aeromagnetic data. Aeromagnetic data have been reprocessed to image with greater detail the structural framework along the western flank of the Victoria Land Basin. New processing includes 2D Werner and 3D Euler deconvolution, the production of maps of the maximum horizontal gradient of pseudo-gravity, and 2D, 3D modelling. Magnetic trends and anomalies are discussed in conjunction with now available drilling results from the CRP, existing bathymetric data and recently published interpretations of a multichannel seismic reflection survey

Efectividad del aceite esencial de orégano mexicano de República Dominicana (Lippia graveolens) contra plagas del maíz (Sitophilus zeamais y Fusarium verticillioides)

The insecticidal and antifungal properties of Mexican oregano (Lippia graveolens) essential oil from the Dominican Republic were investigated under laboratory conditions against two main pests of stored grains: Sitophilus zeamais and Fusarium verticillioides. Although oregano essential oil at 600 ?l/l air did not result in a significant mortality of S. zeamais after 24 hours of exposure by fumigation, this essential oil was a powerful acetylcholinesterase (AChE) inhibitor in vitro. One of the main components of oregano essential oil, p-cymene, presented fumigant toxicity and AChE inhibition activity against the maize weevil. The L. graveolens essential oil antifungal activity against F. verticillioides was evaluated at 50, 100 and 200 ?l/l, and it was found that growth parameters were affected by the presence of oregano essential oil in the media, whereas FB1 production was not inhibited. The results demonstrate that oregano essential oil and p-cymene can be used as alternatives to synthetic pesticides against F. verticillioides and S. zeamais, respectively.Se estudiaron en condiciones de laboratorio las propiedades insecticidas y fungicidas del aceite esencial de orégano mexicano (Lippia graveolens) de República Dominicana contra dos plagas principales de granos almacenados: Sitophilus zeamais y Fusarium verticillioides. Aunque el aceite esencial de orégano a 600 ?l/l de aire no resultó en una mortalidad significativa de S. zeamais después de 24 horas de exposición a la fumigación, fue un potente inhibidor de la acetilcolinesterasa (AChE) in vitro. El p-cimeno, uno de los principales componentes del aceite esencial, presentó actividad fumigante y de inhibición de la AChE contra el gorgojo del maíz. Además se evaluó la actividad antifúngica frente a F. verticillioides a 50, 100 y 200 ?l/l y se encontró que los parámetros de crecimiento del hongo fueron afectados por la presencia del aceite esencial de orégano en el medio, mientras que la producción de fumonisina B1 (FB1) no se inhibió. Los resultados demuestran que el aceite esencial de orégano y el p-cimeno se pueden usar como alternativas a los pesticidas sintéticos contra F. verticillioides y S. zeamais, respectivamente

Unsupervised Monitoring System for Predictive Maintenance of High Voltage Apparatus

The online monitoring of a high voltage apparatus is a crucial aspect for a predictive maintenanceprogram. Partialdischarges(PDs)phenomenaaffecttheinsulationsystemofanelectrical machine and\u2014in the long term\u2014can lead to a breakdown, with a consequent, signi\ufb01cant economic loss; wind turbines provide an excellent example. Embedded solutions are therefore required to monitor the insulation status. The paper presents an online system that adopts unsupervised methodologies for assessing the condition of the monitored machine in real time. The monitoring process does not rely on any prior knowledge about the apparatus; nonetheless, the method can identify the relevant drifts in the machine status. In addition, the system is speci\ufb01cally designed to run on low-cost embedded devices

Relaciones entre el hábitat, demografía y organización social en monos aulladores negros

Los estudios de primates del Nuevo Mundo han sido escasamente abordados dentro de la antropología biológica, ya que no ocupan lugares importantes en estudios de evolución humana. Sin embargo, los estudios evolutivos, deberían incluir comparaciones entre primates para dilucidar principios generales aplicables a todo el Orden. Tras varios años de investigación sobre Alouatta caraya, en Argentina, se encontró que la organización social, la densidad y los patrones de nacimientos varían en ambientes con diferentes ofertas alimenticias. Por un lado, la comparación en cinco sitios diferentes mostró diferencias significativas en tamaño de grupo y densidad de primates que correlacionaron con la disponibilidad de especies con frutos carnosos (p<0.05). Por otro, la comparación de los patrones de nacimientos en dos sitios muestra que donde la oferta de alimentos es estacional, los nacimientos se concentran en la época seca mientras que, donde la oferta de alimentos es continua, los nacimientos ocurren durante todo el año (p<0.01). La variación observada en los patrones de nacimientos y organización social, representaría una respuesta facultativa a cambios en disponibilidad de alimentos, que se traduce en una amplia plasticidad fenotípica para la especie. Esta plasticidad le conferiría ventajas para colonizar un nicho ecológico diverso. Estudios comparativos de este tipo, nos permiten develar patrones y principios validos que no pueden ser identificados solamente con el estudio de la especie humana.Asociación de Antropología Biológica de la República Argentina (AABRA

Contract-Oriented Computing in CO2

We present CO2, a parametric calculus for contract-based computing in distributed systems. By abstracting from the actual contract language, our calculus generalises both the contracts-as-processes and contracts-as-formulae paradigms. The calculus features primitives for advertising contracts, for reaching agreements, and for querying the fulfilment of contracts. Coordination among participants happens via multi-party sessions, which are created once agreements are reached. We present two instances of our calculus, by modelling contracts as processes in a variant of CCS, and as formulae in a logic. We formally relate the two paradigms, through an encoding from contracts-as-formulae to contracts-as-processes which ensures that the promises deducible in the logical system are exactly those reachable by its encoding as a process. Finally, we present a coarse-grained taxonomy of possible misbehaviours in contract-oriented systems, and we illustrate them with the help of a variety of examples