Direccionamiento estratégico de la cooperativa administradora de servicios públicos "Camino Verde APC" para su desarrollo a 2015 - 2018.

Como se puede observar en el presente documento, el Direccionamiento Estratégico brinda a los directores de empresa un sistema de dirección que es un método formal para el análisis situacional, la toma de decisiones y la coordinación de las actividades. Toda empresa u organización necesita un sistema de dirección; no obstante, el nivel de desarrollo de éste depende de la complejidad de la empresa y del entorno con el cual se relaciona. Aquí se encuentran por tanto: una caracterización detallada de la empresa; el estudio de las condiciones que le presentan tanto el macro ambiente (entornos) como el micro ambiente (sector) destacando las oportunidades y amenazas y el impacto que ellas le presentan a la cooperativa; la comparación con empresas similares que permite evaluar la ventaja competitiva; el análisis de la situación interna de la organización identificando las fortalezas y debilidades así como el impacto que ellas producen en la misma; el análisis estratégico usando una serie de matrices (EFI, EFE, DOFA PEYEA) que permiten definir la posición actual; la propuesta de direccionamiento estratégico; y el análisis de la relación costo ¿ beneficio de la propuesta

Time reversal location of glacial earthquakes

In 2003, Ekström et al. reported the detection and location of a new class of earthquakes occurring in the polar regions of the Earth. The proposed source mechanism involves large and sudden sliding motions of glaciers, which gave the name “glacial earthquakes” to these events. In this study we localize some of these earthquakes with a time reversal mirror (TRM) algorithm, which, contrary to ordinary back projection methods, does not involve testing each possible source location. In TRM localization, an earthquake is located on the basis of only one 3-D spectral element simulation of seismic wave propagation by using the full complexity of recorded data as simultaneous time-reversed sources. We show that on the basis of this approach, even glacial earthquakes with a faint signal can be correctly localized and that the pattern of the time-reversed wavefield is coherent with the motion of glaciers down their valley

Time-reversal method and cross-correlation techniques by normal mode theory: a three-point problem

International audienceSince its beginning in acoustics, the Time-Reversal method (hereafter referred as TR) has been explored by different studies to locate and characterize seismic sources in elastic media. But few authors have proposed an analytical analysis of the method, especially in the case of an elastic medium and for a finite body such as the Earth. In this paper, we use a normal mode approach (for general 3-D case and degenerate modes in 1-D reference model) to investigate the convergence properties of the TR method. We first investigate a three-point problem, with two fixed points which are the source and the receiver and a third one corresponding to a changing observation point. We extend the problem of a single channel TR experiment to a multiple channel and multiple station TR experiment. We show as well how this problem relates to the retrieval of Green's function with a multiple source cross-correlation and also the differences between TR method and cross-correlation techniques. Since most of the noise sources are located close to the surface of the Earth, we show that the time derivative of the cross-correlation of long-period seismograms with multiple sources at the surface is different from the Green's function. Next, we show the importance of a correct surface-area weighting of the signal resent by the stations according to a Voronoi tessellation of the Earth surface. We use arguments based on the stationary phase approximation to argue that phase-information is more important than amplitude information for getting a good focusing in TR experiment. Finally, by using linear relationships between the time-reversed displacement (resp. strain wavefields) and the components of a vector force source (resp. a moment tensor source), we show how to retrieve force (or moment tensor components) of any long period tectonic or environmental sources by time reversal

Time-reversal imaging of seismic sources and application to the great Sumatra earthquake

International audienceThe increasing power of computers and numerical methods (like spectral element methods) allows continuously improving modelization of the propagation of seismic waves in heterogeneous media and the development of new applications in particular time reversal in the three-dimensional Earth. The concept of time-reversal (hereafter referred to as TR) was previously successfully applied for acoustic waves in many fields like medical imaging, underwater acoustics and non destructive testing. We present here the first application at the global scale of TR with associated reverse movies of seismic waves propagation by sending back long period time-reversed seismograms. We show that seismic wave energy is refocused at the right location and the right time of the earthquake. When TR is applied to the Sumatra-Andaman earthquake (26 Dec. 2004), the migration of the rupture from the south towards the north is retrieved. Therefore, TR is potentially interesting for constraining the spatio-temporal history of complex earthquakes

A silica long base tiltmeter with high stability and resolution

International audienceIn order to be able to provide valuable data in multiparameter measurement field operations, tiltmeters need to have a noise level better or equal than 10-9 rad for a period range from a few minutes to a few years and a long term stability ranging from 10-7 to 10-8 rad/yr. Tiltmeter measurements should also be as much as possible insensitive to thermal disturbances, by taking great care of the horizontality of the base line tube first. Secondly, thermal responses have been assessed. We also took great care of the coupling of our tiltmeters with the bedrock. We've designed a long base tiltmeter with sensors in silica which has a low dilatation coefficient. The linear variable displacement transducer is based on coil coupling (powered by an alternative voltage). Finally we show the results of two 100 m silica water tube tiltmeters which were installed in a mine in the French Vosges massif in the framework of a hydrology research project. These instruments show a remarkably good stability (6.5×10-9 rad/month) and a low noise level (of the order of 10-11 rad). Toroidal and spheroidal free modes of the Earth were observed after the two last major earthquakes on Sumatra

Time reversal methods in acousto-elastodynamics

The aim of the article is to solve an inverse problem in order to determine the presence and some properties of an elastic “inclusion” (an unknown object, characterized by elastic properties discriminant from the surrounding medium) from partial observa- tions of acoustic waves, scattered by the inclusion. The method will require developing techniques based on Time Reversal methods. A finite element method based on varia- tional acousto-elastodynamics formulation will be derived and used to solve to solve the forward, and then, the time reversed problem. A criterion, derived from the reverse time migration framework, is introduced, to help use to construct images of the inclusions to be determined. Our approach will be applied to configurations modeling breast cancer detection, using simulated ultrasound waves

Obtención y purificación de extractos de la enzima monóxido de carbono deshidrogenasa de Oligotropha carboxidovorans (cepa OM 5) con actividad de oxidación de monóxido de carbono detectable electroquímicamente por medio de un microelectrodo de platin

Extracts of the enzyme carbon monoxide dehydrogenase capable to oxidize carbon monoxide to CO2 were obtained from the carboxidotrophic bacteria Oligotropha carboxidovorans OM5 cultivated under aerobic conditions in a mineral medium saturated with CO. The extracts were obtained disrupting cells by sonication and purification by molecular size-exclusion chromatography and ion-exchange chromatography. The enzymatic activity of the extracts was measured using methylene blue as an artificial electronic acceptor in the oxidation of the CO to CO2. Crude and purified extracts showed enzymatic activity detectable by spectrophotometry. The maximum grade of purification obtained was 200 times and specific enzymatic activities were achieved in the range from 0.01 to 2.0 mU/mg of protein. Electrochemical assays using a platinum microelectrode and methylene blue as an electronic mediator showed an increase of the anodic current when the substrate carbon monoxide was added to the cell that contained the enzymatic extract. These results encourage the construction of an electrochemical biosensor for the detection of carbon monoxide using enzymatic extracts obtained from carboxidotrophic bacteria.Se obtuvieron extractos crudos y purificados de la enzima monóxido de carbono deshidrogenasa capaces de oxidar monóxido de carbono a CO2, a partir de cultivos de la bacteria carboxidotrofa Oligotropha carboxidovorans (cepa OM5) cultivadas aeróbicamente em un medio mineral saturado con CO. Los extractos crudos se obtuvieron mediante la ruptura de las células por sonicación y se purificaron por cromatografía de exclusión molecular y cromatografía de intercambio iónico. La actividad enzimática de los extractos se midió utilizando azul de metileno como aceptor electrónico artificial en la oxidación del CO a CO2. Se obtuvieron extractos crudos y purificados con actividad enzimática detectable por medio de espectrofotometría. El grado máximo de purificación obtenido fue de 200 veces y se lograron actividades enzimáticas específicas en el rango de 0.01 a 2.0 mU/mg de proteína. Ensayos electroquímicos usando un microelectrodo deplatino y azul de metileno como mediador electrónico, mostraron un aumento de la corriente anódica cuando se adicionó el sustrato monóxido de carbono a la celda que contenía el extracto enzimático. Estos resultados permiten alentar la construcción de un biosensor electroquímico para la detección de monóxido de carbono, utilizando extractos enzimáticos obtenidos a partir de bacterias carboxidotrofas

Seismic constraints from a Mars impact experiment using InSight and Perseverance

NASA’s InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) mission has operated a sophisticated suite of seismology and geophysics instruments on the surface of Mars since its arrival in 2018. On 18 February 2021, we attempted to detect the seismic and acoustic waves produced by the entry, descent and landing of the Perseverance rover using the sensors onboard the InSight lander. Similar observations have been made on Earth using data from both crewed1,2 and uncrewed3,4 spacecraft, and on the Moon during the Apollo era5, but never before on Mars or another planet. This was the only seismic event to occur on Mars since InSight began operations that had an a priori known and independently constrained timing and location. It therefore had the potential to be used as a calibration for other marsquakes recorded by InSight. Here we report that no signal from Perseverance’s entry, descent and landing is identifiable in the InSight data. Nonetheless, measurements made during the landing window enable us to place constraints on the distance–amplitude relationships used to predict the amplitude of seismic waves produced by planetary impacts and place in situ constraints on Martian impact seismic efficiency (the fraction of the impactor kinetic energy converted into seismic energy)

Understanding The Correlation Of Libs And Acoustic Measurements Of Rocks And Soils Found In The Traverse Of The Perseverance Rover Across The Jezero Crater, Mars

The SuperCam instrument of the NASA MARS 2020 Perseverance rover combines a suite of atomic and molecular spectroscopies intended for an extensive description of rocks, soils and minerals in the surroundings of the landing site of the mission – the Jezero crater. The microphone installed on the SuperCam instrument allows the acquisition of acoustic signals resulting from the expansion of laser-induced plasmas towards the atmosphere. Apart from being affected by the propagation characteristics of the Mars atmosphere, the acoustic signal has an additional component related to the properties of the target including surface morphology, hardness, deformation parameters, and elasticity, among others. This information is currently being investigated as a complementary resource for characterization of the ablated material and may well supplement the LIBS data gathered from coincident laser shots. This talk will present SuperCam acoustic data of rocks and minerals found in the traverse of the Perseverance rover and will discuss its correlation with LIBS spectra.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

LIBS and Acoustic Measurements of Rocks and Regolith Found in the Traverse of the Perseverance Rover Across the Jezero Crater, Mars

The SuperCam instrument of the NASA MARS 2020 Perseverance rover combines a suite of atomic and molecular spectroscopies intended for an extensive description of rocks, soils and minerals in the surroundings of the landing site of the mission – the Jezero crater. The microphone installed on the SuperCam instrument allows the acquisition of acoustic signals resulting from the expansion of laser-induced plasmas towards the atmosphere. Apart from being affected by the propagation characteristics of the Mars atmosphere, the acoustic signal has an additional component related to the properties of the target including surface morphology, hardness, deformation parameters, and elasticity, among others. This information is currently being investigated as a complementary resource for characterization of the ablated material and may well supplement the LIBS data gathered from coincident laser shots. This talk will present SuperCam acoustic data of rocks and minerals found in the traverse of the Perseverance rover and will discuss its correlation with LIBS spectra.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec