69 research outputs found
Propuesta de acondicionamiento acústico del estudio 4 del Canal RCN Televisión.
Propuesta de Acondicionamiento Acústico del Estudio 4 del Canal RCN Televisión
El objetivo principal de esta tesis fue realizar la propuesta de acondicionamiento acústico para el estudio de televisión número 4, la cual tenía que ser accesible con lo que dispuso el canal RCN Televisión en su momento.
Se realizaron mediciones de parámetros como: Tiempo de reverberación, geometría de la sala, ruido de fondo, curvas NC, entre otros; con estos resultados se realizo una comparación de las distintas normativas y criterios existentes permitiendo establecer la necesidad de tratar acústicamente el recinto, dado que se encontraron falencias acústicas, lo cual interrumpe el debido cumplimiento de los estándares de calidad para estudios de televisión.Acoustic conditioning proposal for studio 4 of the RCN television channel
The main objective of this thesis was to make a proposal of acoustic conditioning for the television studio number 4, which had to be accessible with everything the channel RCN Television, had at the time.
All measurements were made of parameters such as: Reverberation time, room geometry, background noise, NC curves, among others; With these results, a comparison of the different existing standards and criteria was made, establishing the need to acoustically treat the enclosure, because of the acoustic deficiencies were found, which interrupts the proper compliance with the quality standards for television studios
Seroprevalence of exposure to SARS-CoV-2 in domestic dogs and cats and its relationship with COVID-19 cases in the city of Villavicencio, Colombia [version 3; peer review: 2 approved]
Background: Since the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak, different animal species have been implicated as possible intermediate hosts that could facilitate the transmission of the virus between species. The detection of these hosts has intensified, reporting wild, zoo, farm, and pet animals. The goal of this study was to determine the seroprevalence of anti-SARS-CoV-2 immunoglobulins (IgG) in domestic dogs and cats and its epidemiological association with the frequency of coronavirus disease 2019 (COVID-19) patients in Villavicencio, Colombia. Methods: 300 dogs and 135 cats were randomly selected in a two-stage distribution by clusters according to COVID-19 cases (positive RT-qPCR for SARS-CoV-2) within the human population distributed within the eight communes of Villavicencio. Indirect enzyme-linked immunosorbent assay (ELISA) technique was applied in order to determine anti-SARS-CoV-2 IgG in sera samples. Kernel density estimation was used to compare the prevalence of COVID-19 cases with the seropositivity of dogs and cats. Results: The overall seroprevalence of anti-SARS-CoV-2 IgG was 4.6% (95% CI=3.2-7.4). In canines, 3.67% (95% CI=2.1-6.4) and felines 6.67% (95% CI=3.6-12.18). Kernel density estimation indicated that seropositive cases were concentrated in the southwest region of the city. There was a positive association between SARS-CoV-2 seropositivity in pet animals and their habitat in Commune 2 (adjusted OR=5.84; 95% CI=1.1-30.88). Spearman's correlation coefficients were weakly positive (p=0.32) between the ratio of COVID-19 cases in November 2020 and the results for domestic dogs and cats from the eight communes of Villavicencio. Conclusions: In the present research cats were more susceptible to SARS-CoV-2 infection than dogs. This study provides the first positive results of anti-SARS-CoV-2 ELISA serological tests in domestic dogs and cats in Colombia with information about the virus transmission dynamics in Latin America during the COVID-19 pandemic
Trayectorias de un viaje por la investigación educativa desde el sentipensar de los maestros y maestras : experiencias en desarrollo del programa de pensamiento crítico
428 páginasEste libro reúne 19 experiencias que continúan el acompañamiento en la fundamentación, desarrollo y estructuración de estrategias de tipo pedagógico y didáctico dentro de la ruta sentipensante en el Nivel II: Experiencias en desarrollo. Igualmente, en estas experiencias se hace una ampliación de referentes, técnicas e instrumentos para recoger información de los 19 textos presentados. De tal manera, estas experiencias son fruto de este acompañamiento que ha realizado el Instituto para la Investigación Educativa y el Desarrollo Pedagógico IDEP, que servirán de base y referente para seguir aportando en la configuración y consolidación de comunidades de saber y práctica pedagógica, así como en la conformación de colectivos y redes de maestros y maestras
A search for ultra-high-energy photons at the Pierre Auger Observatory exploiting air-shower universality
The Pierre Auger Observatory is the most sensitive detector to primary photons with energies above ∼0.2 EeV. It measures extensive air showers using a hybrid technique that combines a fluorescence detector (FD) with a ground array of particle detectors (SD). The signatures of a photon-induced air shower are a larger atmospheric depth at the shower maximum (X) and a steeper lateral distribution function, along with a lower number of muons with respect to the bulk of hadron-induced background. Using observables measured by the FD and SD, three photon searches in different energy bands are performed. In particular, between threshold energies of 1-10 EeV, a new analysis technique has been developed by combining the FD-based measurement of X with the SD signal through a parameter related to its muon content, derived from the universality of the air showers. This technique has led to a better photon/hadron separation and, consequently, to a higher search sensitivity, resulting in a tighter upper limit than before. The outcome of this new analysis is presented here, along with previous results in the energy ranges below 1 EeV and above 10 EeV. From the data collected by the Pierre Auger Observatory in about 15 years of operation, the most stringent constraints on the fraction of photons in the cosmic flux are set over almost three decades in energy
Study on multi-ELVES in the Pierre Auger Observatory
Since 2013, the four sites of the Fluorescence Detector (FD) of the Pierre Auger Observatory record ELVES with a dedicated trigger. These UV light emissions are correlated to distant lightning strikes. The length of recorded traces has been increased from 100 μs (2013), to 300 μs (2014-16), to 900 μs (2017-present), to progressively extend the observation of the light emission towards the vertical of the causative lightning and beyond. A large fraction of the observed events shows double ELVES within the time window, and, in some cases, even more complex structures are observed. The nature of the multi-ELVES is not completely understood but may be related to the different types of lightning in which they are originated. For example, it is known that Narrow Bipolar Events can produce double ELVES, and Energetic In-cloud Pulses, occurring between the main negative and upper positive charge layer of clouds, can induce double and even quadruple ELVES in the ionosphere. This report shows the seasonal and daily dependence of the time gap, amplitude ratio, and correlation between the pulse widths of the peaks in a sample of 1000+ multi-ELVES events recorded during the period 2014-20. The events have been compared with data from other satellite and ground-based sensing devices to study the correlation of their properties with lightning observables such as altitude and polarity
Extraction of the Muon Signals Recorded with the Surface Detector of the Pierre Auger Observatory Using Recurrent Neural Networks
We present a method based on the use of Recurrent Neural Networks to extract the muon component from the time traces registered with water-Cherenkov detector (WCD) stations of the Surface Detector of the Pierre Auger Observatory. The design of the WCDs does not allow to separate the contribution of muons to the time traces obtained from the WCDs from those of photons, electrons and positrons for all events. Separating the muon and electromagnetic components is crucial for the determination of the nature of the primary cosmic rays and properties of the hadronic interactions at ultra-high energies.
We trained a neural network to extract the muon and the electromagnetic components from the WCD traces using a large set of simulated air showers, with around 450 000 simulated events. For training and evaluating the performance of the neural network, simulated events with energies between 1018.5, eV and 1020 eV and zenith angles below 60 degrees were used. We also study the performance of this method on experimental data of the Pierre Auger Observatory and show that our predicted muon lateral distributions agree with the parameterizations obtained by the AGASA collaboration
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