Artificial Neural Networks applied to improve low-cost air quality monitoring precision

It is a fact that air pollution is a major environmental health problem that affects everyone, especially in urban areas. Furthermore, the cost of high-end air pollution monitoring sensors is considerably high, so public administrations are unable to afford to place an elevated number of measuring stations, leading to the loss of information that could be very helpful. Over the last few years, a large number of low-cost sensors have been released, but its use is often problematic, due to their selectivity and precision problems. A calibration process is needed in order to solve an issue with many parameters with no clear relationship among them, which is a field of application of Machine Learning. The objectives of this project are first, integrating three low-cost air quality sensors into a Raspberry Pi and then, training an Artificial Neural Network model that improves precision in the readings made by the sensors.Es un hecho que la contaminación del aire es un gran problema para la salud a nivel mundial, especialmente en zonas urbanas. Además, el coste de los sensores de contaminación de gama alta es considerablemente alto, por lo que los organismos públicos no pueden permitirse emplazar un gran número de estaciones de medida, perdiendo información que podría ser muy útil. A lo largo de los últimos años, han surgido muchos sensores de contaminación de bajo coste, pero su uso suele ser complicado, ya que tienen problemas de selectividad y precisión. Los objetivos de este proyecto son primero integrar tres sensores de contaminación de bajo coste en una Raspberry Pi y sobre todo, entrenar un modelo basado en una red neuronal artificial que mejore la precisión de las lecturas realizadas por los sensores.Està demostrat que la contaminació de l'aire és un gran problema per a la salut a nivell mundial, especialment en zones urbanes. A més, el cost dels sensors de contaminació de gama alta és considerablement alt, motiu pel qual els organismes públics no es poden permetre emplaçar una gran quantitat d'estacions de mesura, perdent informació que podria resultar molt útil. Al llarg dels últims anys, han sorgit molts sensors de contaminació de baix cost, però el seu ús és sovint complicat, ja que tenen problemes de selectivitat i precisió. Els objectius d'aquest projecte són primer de tot integrar tres sensors de contaminació de baix cost en una Raspberry Pi i sobretot, entrenar un model basat en una xarxa neuronal artificial que millori la precisió de les lectures realitzades pels sensors

Analysis of Latin America's Corporations as a Rational Response to the Economic Environment Present in the Region - Part I

This is the first of a series of working papers analyzing the basic characteristics of the economic environment in which Latin American Corporations live and the optimal design of incentive programs compatible with such environment. By economic environment we mean the technology that the organizations have access to, the legal framework present in these countries, the macro-economical characteristics, the markets in which they operate (competitors, monopolies, customers, reliability of suppliers, etc.), the nature of their capital markets and in general of the sources of financing for their companies, etc. We could broadly say that any key feature of the economy that has the potential to influence the way business is run in Latin America is part of its economic environment. The underlying unifying idea in this series is that, unless we have clear evidence to the contrary, corporate practices observed in Latin American firms are rational responses to the environment in which they operate. They are a sort of Darwinian adaptation to such environment. Therefore, much like in biological systems, these characteristics of corporations should be considered optimal in a relative sense. That is, in order to survive in the market, the observed corporate practices should be better that the ones from the competition for the given economic environment. This observation suggests that improvements to the observed practices are indeed possible. In fact, the present series of working papers is in part structured to explore possible improvements. These improvements, however, are not likely to be the simple copy of corporate practices that evolved as an optimal response to the environment of the developed world. In this first work we present some important empirical characteristics of the Latin American Corporations and the first key aspect of the economic environment prevailing in this region: the legal framework. We show how many of the empirical characteristics presented can be see as optimal responses to the legal framework.

Quantifying Latin American firms'exposure to external factors

This is the last of a series of three working papers analyzing the basic characteristics of the economic environment in which Latin American firms operate and the optimal design of incentive programs compatible with such environment. Executive pay-for-performance compensation schemes are usually based on stock returns. However, stock returns change in response to forces beyond management control (e.g., market crushes). The economic environment in which Latin American firms operate is highly unstable, which means that this is a very important limitation for Latin American firms. In the present paper, we present a procedure to decompose variability in stock returns in order to identify and measure components that respond to external factors beyond management control. For this, we have created indices that capture statistically the external influences that affect stock returns. We show how such indices can be used to construct a risk profile that allows management to know to what extent observed outcomes depend on external factors, versus their own actions. In addition, these indices can be used as a basis to develop "indexed options": financial instruments designed to factor out the effects of external risks, making it possible for executives to be evaluated only on the basis of the value they generate. We show that these indices can be developed out of purely local information, but that the solutions tend to be moderately unstable, which implies that compensation instruments developed with this methodology should be of relatively short maturity.

Coupled mantle dripping and lateral dragging controlling the lithosphere structure of the NW-Moroccan margin and the Atlas Mountains: A numerical experiment

Recent studies integrating gravity, geoid, surface heat flow, elevation and seismic data indicate a prominent lithospheric mantle thickening beneath the NW-Moroccan margin (LAB >200 km-depth) followed by thinning beneath the Atlas Domain (LAB about 80 km-depth). Such unusual configuration has been explained by the combination of mantle underthrusting due to oblique Africa-Eurasia convergence together with viscous dripping fed by asymmetric lateral mantle dragging, requiring a strong crust-mantle decoupling. In the present work we examine the physical conditions under which the proposed asymmetric mantle drip and drag mechanism can reproduce this lithospheric configuration. We also analyse the influence of varying the kinematic boundary conditions as well as the mantle viscosity and the initial lithosphere geometry. Results indicate that the proposed drip-drag mechanism is dynamically feasible and only requires a lateral variation of the lithospheric strength. The further evolution of the gravitational instability can become either in convective removal of the lithospheric mantle, mantle delamination, or subduction initiation. The model reproduces the main trends of the present-day lithospheric geometry across the NW-Moroccan margin and the Atlas Mountains, the characteristic time of the observed vertical movements, the amplitude and rates of uplift in the Atlas Mountains and offers an explanation to the Miocene to Pliocene volcanism. An abnormal constant tectonic subsidence rate in the margin is predicted. (C) 2013 Elsevier B.V. All rights reserved.Peer ReviewedPostprint (author's final draft

Heidegger y la Etica

Una pregunta se puso de moda a finales de la década de los ochenta con motivo de la publicación del libro del chileno Víctor Farías "Heidegger y el nazismo". Una pregunta que incomodó a sus seguidores y entregó argumentos adicionales a sus detractores: ¿Qué relación puede existir entre el pensamiento teórico del filósofo alemán Martin Heidegger y su apoyo público al nacional-socialismo? Estas reacciones se pueden considerar como motivadas por una valoración ética de la relación entre vida y obra de un filósofo

Habermas y la Teoría Crítica de la Sociedad

La escuela de la Teoría Crítica de la sociedad tuvo como baluarte el texto "Dialéctica de la Ilustración" escrito por Max Horkheimer y Teodoro Adorno durante su exilio en Estados Unidos en el primer lustro de los años 40. En el Prólogo los autores se lamentan del deplorable estado de la tradición científica occidental, sostienen que pese a los avances de la actividad científica moderna ellos mismos "se pagan con una creciente decadencia de la cultura teórica" además de que si bien el cultivo de la tradición científica es un momento indispensable del conocimiento, "en la quiebra de la civilización burguesa se ha hecho cuestionable no sólo la organización sino el sentido mismo de la ciencia"

Mente, Representaciones y Ciencia

En el primer volumen de sus Escritos Filosóficos, publicado en inglés en 1991, el filósofo norteamericano Richard Rorty propone una explicación antirrepresentacionalista de la relación entre la ciencia natural y el resto de la cultura. Esto es una explicación según la cual "el conocimiento no consiste en la aprehensión de la verdadera realidad, sino en la forma de adquirir hábitos para hacer frente a la realidad" (Rorty 1991:15). La relevancia de esta tesis para la filosofía de la ciencia es que dicha explicación no reconoce diferencias epistemológicas entre una explicación, por ejemplo, de la física teórica y otra de la crítica literaria. Es una tesis fuerte que tiene como consecuencia, entre otras, borrar la distinción entre fenómenos "duros" y "blandos" aduciendo lo innecesario de la distinción misma

Epistemología y Psicoanálisis

Las tesis del presente trabajo las puedo resumir como sigue: las críticas al psicoanálisis del neopositivismo y del falsacionismo son contundentes si el psicoanálisis se autoconcibe como ciencia del método experimental u observacional. La teoría del inconsciente como cosa no puede ser falsada, por consiguiente, Ricoeur y Habermas aciertan al reinterpretarla como hermenéutica o teoría del lenguaje. Pero dicho intento va a contrapelo de la autoconcepción de Freud quien, alega Arnold Modell, se consideraba al mismo tiempo como un científico natural y un arqueólogo del psiquismo