7,266 research outputs found

    Factores que afectan el uso de prácticas de gestión del riesgo en los proyectos del sector minero energético en Colombia

    Get PDF
    139 páginasA pesar de la necesidad, beneficios y efectividad de la implementación de sistemas de gestión de riesgos, investigadores afirman que las organizaciones que han tenido éxito en la aplicación de esta práctica se encuentran todavía en una pequeña minoría que no supera el 25º/o. Por lo anterior, se hace necesario entender los factores que afectan el buen uso de prácticas de gestión de riesgos en los proyectos desarrollados en Colombia, analizar el grado de compromiso de gerentes y profesionales involucrados en el proceso. Es así, como el presente trabajo de grado tiene como objeto analizar el manejo del riesgo en proyectos, específicamente en los ejecutados en el sector Minero Energético en Colombia, un sector que se ha convertido en el sector más dinámico e importante de la economía del país y por lo tanto, un sector lleno de incertidumbres con incidencias positivas o negativas dependiendo de su comportamiento; con el propósito de identificar aquellos factores que lo afectan y conocer las causas que impiden o dificultan que la gestión del riesgo sea una práctica implementada de forma eficiente.Despite the need, benefits and effectiveness of the implementation of risk management systems, researchers say that organizations that have succeeded in implementing this practice are still in a small minority that doesn't exceed 25o/o. Due to the above, it is necessary to understand !he factors that affect the good use of risk management practices in projects developed in Colombia, to analyze the degree of commitment of managers and professionals involved in process. Thus. the present thesis aims to analyze the risk management in projects, specifically those executed in !he Mining Energy sector in Colombia, a sector that has become the most dynamic and important sector of the country's economy and therefore, a sector full of uncertainties with positive or negative incidents depending on their behavior; with the purpose of identifying those factors that affect it and knowing the causes that impede or make it difficult for risk management to be an efficiently implemented practice.Magíster en Gestión y Evaluación de Proyectos de InversiónMaestrí

    Electrooxidation-Ozonation: A Synergistic Sustainable Wastewater Treatment Process

    Get PDF
    Advanced oxidation processes (AOPs) have shown to be very useful technologies for application in different wastewater treatment areas. These processes use the very strong oxidizing power of hydroxyl radicals to oxidize organic compounds to carbon dioxide and water. These procedures usually involve the use of O3, H2O2, Fenton’s reagent and electrolysis to generate the hydroxyl radicals. However, some recent investigations have found that the use of a coupled processes using O3/electrooxidation increases the effectiveness of the process and also could reduce the operating costs associated to the application of AOPs. In this chapter, there is a description of our work in the treatment of wastewater using an ozonation-electrooxidation combined process. The main parameters to control for having a successful application of such method are discussed. Several examples for different kinds of polluted water are addressed

    Chain Homotopies for Object Topological Representations

    Get PDF
    This paper presents a set of tools to compute topological information of simplicial complexes, tools that are applicable to extract topological information from digital pictures. A simplicial complex is encoded in a (non-unique) algebraic-topological format called AM-model. An AM-model for a given object K is determined by a concrete chain homotopy and it provides, in particular, integer (co)homology generators of K and representative (co)cycles of these generators. An algorithm for computing an AM-model and the cohomological invariant HB1 (derived from the rank of the cohomology ring) with integer coefficients for a finite simplicial complex in any dimension is designed here. A concept of generators which are "nicely" representative cycles is also presented. Moreover, we extend the definition of AM-models to 3D binary digital images and we design algorithms to update the AM-model information after voxel set operations (union, intersection, difference and inverse)

    La mirada no hegemónica en la recuperación de los saberes tradicionales

    Get PDF
    Hoy en día, en México, los saberes tradicionales en ciertas áreas de la medicina se han incorporado a algunas instituciones de salud pública; sin embargo, se presentan como alternativos, sin el reconocimiento pleno de la medicina moderna. Se establecen relaciones de poder que los ubica en la marginalidad del conocimiento, ocultando la riqueza cultural y negando las prácticas sociales que son fuente de conocimiento. Bajo este enfoque alterno están las mujeres parteras, quienes han sido incorporadas a algunas instituciones de salud, donde se les exige seguir las reglas de la modernidad como son los cursos de capacitación y los procedimientos de asepsia, entro otros.La ciencia moderna se construye bajo las metáforas propias de la modernidad y ha promovido un único discurso de la verdad y un orden social que reproduce el orden jerárquico y desigual del sistema mundo; ha dejado de lado los saberes culturales y tradicionales de los distintos pueblos. Sin embargo, es importante recuperar el diálogo epistemológico de los saberes populares que nuestros pueblos construyen y recuperan como estrategias y tácticas de subsistencia y resistencia en los contextos de exclusión y marginación a los que son sometidos por las racionalidades del sistema social (cfr. de Sousa Santos, 2009). Los saberes tradicionales han sido excluidos de lo que se denomina ciencia moderna, misma que es cuestionada por los estudios de la decolonialidad; dichos saberes han sido invisibilizados y discriminados por el mundo occidental. México cuenta con una gran diversidad de saberes, es común encontrar en los diferentes sectores de su población conocimientos propios, creencias y costumbres acerca de la salud y la enfermedad; dichos conocimientos se derivan de las culturas indígenas locales y del sincretismo cultural que tuvo lugar después de la conquista en el siglo XVI

    Implementation of the K-Means Algorithm on Heterogeneous Devices: A Use Case Based on an Industrial Dataset

    Get PDF
    This paper presents and analyzes a heterogeneous implementation of an industrial use case based on K-means that targets symmetric multiprocessing (SMP), GPUs and FPGAs. We present how the application can be optimized from an algorithmic point of view and how this optimization performs on two heterogeneous platforms. The presented implementation relies on the OmpSs programming model, which introduces a simplified pragma-based syntax for the communication between the main processor and the accelerators. Performance improvement can be achieved by the programmer explicitly specifying the data memory accesses or copies. As expected, the newer SMP+GPU system studied is more powerful than the older SMP+FPGA system. However the latter is enough to fulfill the requirements of our use case and we show that uses less energy when considering only the active power of the execution.This work is partially supported by the European Union H2020 project AXIOM (grant agreement n. 645496), HiPEAC (grant agreement n. 687698), and Mont-Blanc (grant agreements n. 288777, 610402 and 671697), the Spanish Government Programa Severo Ochoa (SEV-2015-0493), the Spanish Ministry of Science and Technology (TIN2015- 65316-P) and the Departament d’Innovació, Universitats i Empresa de la Generalitat de Catalunya, under project MPEXPAR: Models de Programaci´o i Entorns d’Execució Paral·lels (2014-SGR-1051).Peer ReviewedPostprint (author's final draft

    Integrated analysis of root microbiomes of soybean and wheat from agricultural fields

    Get PDF
    Root associated bacteria are critical for plant growth and health. Understanding the composition and role of root microbiota is crucial toward agricultural practices that are less dependent on chemical fertilization, which has known negative effects on the environment and human health. Here we analyzed the root-associated microbiomes of soybean and wheat under agricultural field conditions. We took samples from 11 different production fields across a large geographic area. We used 16S rRNA pyrosequencing to explore root microbial communities and also obtained 2,007 bacterial isolates from rhizospheres, which were tested for the presence of plant growth promoting (PGP) traits in-vitro. We observed that pH and nitrate content correlated with beta diversity variability of rhizospheric bacterial communities despite the variable field conditions. We described the dominant bacterial groups associated to roots from both crops at a large geographic scale and we found that a high proportion of them (60-70%) showed more than 97% similarity to bacteria from the isolated collection. Moreover, we observed that 55% of the screened isolates presented PGP activities in vitro. These results are a significant step forward in understanding crop-associated microbiomes and suggest that new directions can be taken to promote crop growth and health by modulating root microbiomes.Fil: Rascovan, Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Agrobiotecnología de Rosario; ArgentinaFil: Carbonetto, María Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Agrobiotecnología de Rosario; ArgentinaFil: Perrig, Diego Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Rizobacter Argentina S. A.; ArgentinaFil: Diaz, Marisa. Rizobacter Argentina S. A.; ArgentinaFil: Canciani, Wilter. Rizobacter Argentina S. A.; ArgentinaFil: Abalo, Matías. Rizobacter Argentina S. A.; ArgentinaFil: Alloati, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Agrobiotecnología de Rosario; ArgentinaFil: González Anta, Gustavo. Rizobacter Argentina S. A.; ArgentinaFil: Vazquez, Martin Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Agrobiotecnología de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentin

    Dark Energy Accretion onto black holes in a cosmic scenario

    Get PDF
    In this paper we study the accretion of dark energy onto a black hole in the cases that dark energy is equipped with a positive cosmological constant and when the space-time is described by a Schwarzschild-de Sitter metric. It is shown that, if confronted with current observational data, the results derived when no cosmological constant is present are once again obtained in both cases.Comment: 7 pages, 3 figure

    Reformulation of the symmetries of first-order general relativity

    Get PDF
    We report a new internal gauge symmetry of the n-dimensional Palatini action with cosmological term (n>3) that is the generalization of three-dimensional local translations. This symmetry is obtained through the direct application of the converse of Noether's second theorem on the theory under consideration. We show that diffeomorphisms can be expressed as linear combinations of it and local Lorentz transformations with field-dependent parameters up to terms involving the variational derivatives of the action. As a result, the new internal symmetry together with local Lorentz transformations can be adopted as the fundamental gauge symmetries of general relativity. Although their gauge algebra is open in general, it allows us to recover, without resorting to the equations of motion, the very well-known Lie algebra satisfied by translations and Lorentz transformations in three dimensions. We also report the analog of the new gauge symmetry for the Holst action with cosmological term, finding that it explicitly depends on the Immirzi parameter. The same result concerning its relation to diffeomorphisms and the open character of the gauge algebra also hold in this case. Finally, we consider the non-minimal coupling of a scalar field to gravity in n dimensions and establish that the new gauge symmetry is affected by this matter field. Our results indicate that general relativity in dimension greater than three can be thought of as a gauge theory.We thank Alejandro Perez, Carlo Rovelli, José D Vergara, and José A Zapata for their valuable comments. This work was supported in part by Consejo Nacional de Ciencia y Tecnología (CONACyT), México, Grant No. 237004-F

    Bar_Code Housing System: la creación de un espacio de investigación interdisciplinar en torno al proyecto de arquitectura

    Get PDF
    BAR_CODE HOUSING SYSTEM es un proyecto de investigación sobre la vivienda colectiva construida con sistemas industrializados financiado por el Plan Nacional de I+D+i. El objetivo del proyecto es desarrollar un sistema integrado de diseño y construcción asistido por ordenador que facilite la interacción ente los agentes que participan en los procesos de diseño y construcción de viviendas (técnicos, constructores, fabricantes, administración, usuarios). La investigación abarca diversos ámbitos de la arquitectura (proyectos, construcción, estructuras, instalaciones), conjuntamente con la computación. Las tecnologías de la información y comunicación se aplican con la intención de potenciar las relaciones entre estos ámbitos. La interrelación entre las distintas disciplinas y áreas de conocimiento da lugar a un espacio de investigación de carácter transdisciplinar, aunque esencialmente arquitectónico. Esta estrategia de relaciones propicia la vinculación entre la investigación y la docencia, especialmente cuando se adopta un modelo de educación constructivista
    corecore