1,720,959 research outputs found
Urban air pollution evaluation in downtown streets of a medium-sized Latin American city using AERMOD dispersion model
No full textThe transport sector is considered the largest contributor of air pollutants in urban areas, mainly on-road vehicles, afecting the environment and human health. Bahía Blanca is a medium-sized Latin American city, with high levels of trafc in the downtown area during peak hours. In this regard, it is necessary to analyze air pollution using an air quality model considering that there are no air pollutant measurements in the central area. Furthermore, this type of study has not been carried out in the region and since the city is expected to grow, it is necessary to evaluate the current situation in order to make efective future decisions. In this sense, the AERMOD model (US-EPA version) and the RLINE source type were used in this work. This study analyzes the variations of pollutant concentrations coming from mobile sources in Bahía Blanca’s downtown area, particularly carbon monoxide (CO) and nitrogen oxides (NOx) during the period Jul-2020 to Jun-2022. It is interesting to note the results show the maximum concentration values detected are not directly associated with maximum levels of vehicle fow or emission rates, which highlights the importance of meteorological parameters in the modeling. In addition, alternative scenarios are proposed and analyzed from a sustainable approach. Regarding the scenario analysis, it can be concluded that diesel vehicles have a large infuence on NOx emissions. Moreover, restrictions as strict as those proposed for a Low Emission Zone would be less applicable in the city than alternative temporary measures that modify traffc at peak hours.Fil: Grassi, Yamila Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Diaz, Monica Fatima. Universidad Nacional del Sur. Departamento de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentin
Vehicular fleet characterisation and assessment of the on-road mobile source emission inventory of a Latin American intermediate city
No full textThe management of urban mobile-source emissions is nowadays a challenging topic. This paper describes a comprehensive and practical analysis of the vehicular fleet characterisation and the 2018 on-road mobile source emission inventory for Bahía Blanca (Argentina), a medium-size Latin American city. An exhaustive segmentation of the vehicle fleet was done to obtain more real results from the emission inventory carried out by COPERT software. Results for 2018, allow us to conclude that motorcycles were the main source of CO, NMVOC, CO2 and CH4. While, light commercial vehicles were the ones that emitted the most amount of NOx. Finally, it was concluded that the polluting emissions observed in 2013 are higher than the 2018's ones, in spite of the growth of the vehicular fleet (12.45% in 2018 respect to 2013). This may mainly be due to the incorporation of a new, more efficient emission control technology in vehicular fleet of 2018. However, these improvements result in increased GHGs emissions, which is still a challenge in this area. Finally, the main trends for vehicle flow and emissions detected in 2020 are presented.Fil: Grassi, Yamila Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Brignole, Nélida Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. Universidad Nacional del Sur. Departamento de Ciencias e Ingeniería de la Computación. Laboratorio de Investigación y Desarrollo en Computación Científica; ArgentinaFil: Diaz, Monica Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. Universidad Nacional del Sur. Departamento de Ingeniería Química; Argentin
Effects of Covid-19 pandemic on urban mobility in Bahía Blanca (Argentina) during the second semester of 2020
Full text linkThis article analyzes the effects of the COVID-19 pandemic on urban mobility in the downtown area of Bahía Blanca city, Argentina. The traffic flow and the segmentation of the vehicle fleet have been compiled by manual counting using the filmographic material generated by the security cameras of the local townhall, during the second half of 2020. The generated data allow to obtain an initial diagnosis of the changes in the type of mobility chosen by citizens, as well as the variations that occurred in vehicular flow. The analysis revealed an increase in traffic flow in the month of December, which is consistent with the gradual reopening of the lockdown. Besides, in the study of the extreme months of the period, i.e. July and December 2020, an increase in the use of motorcycles and bicycles was detected, thus reducing the appearance of the car. Therefore, it can be inferred that the citizens migrated to another type of cheaper mobility, and also more ecological and sustainable in the case of bicycles.Fil: Grassi, Yamila Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Brignole, Nélida Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. Universidad Nacional del Sur. Departamento de Ciencias e Ingeniería de la Computación. Laboratorio de Investigación y Desarrollo en Computación Científica; ArgentinaFil: Diaz, Monica Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. Universidad Nacional del Sur. Departamento de Ingeniería Química; ArgentinaXXXVII Congreso Interamericano de Ingeniería Sanitaría y AmbientalBuenos AiresArgentinaAsociación Argentina de Ingeniería Sanitaria y Ciencias del AmbienteAsociación Interamericana de Ingeniería Sanitari
Pandemic impact on air pollution and mobility in a Latin American medium-size city
No full textThe COVID-19 pandemic has affected lifestyles everywhere, changing urban traffic circulation worldwide. This paper focuses on the impact of the pandemic on air pollution from mobile sources in a Latin American medium-size city: Bahía Blanca (Argentina). Vehicle flow and corresponding emissions were evaluated before (January and March 2020) and after (June and November 2020) the lockdown. Vehicular traffic flows were measured and their segmentations were calculated. Emissions dispersion was modelled by employing R-Line, through the use of AERMOD. A decrease was observed not only in vehicular flow (~23%), but also in pollutant and greenhouse gas concentrations (~70%), in line with other research. Changes in mobility habits were observed, which were reflected by the different proportion of the vehicle-fleet segmentation, with a significant drop in the buses (~66%) together with the appearance of a bicycle peak (~53%), which is unusual for the city.Fil: Grassi, Yamila Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Brignole, Nélida Beatriz. Universidad Nacional del Sur. Departamento de Ciencias e Ingeniería de la Computación. Laboratorio de Investigación y Desarrollo en Computación Científica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Diaz, Monica Fatima. Universidad Nacional del Sur. Departamento de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentin
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Contaminación atmosférica debido a fuente4s móviles en la ciudad de Bahía Blanca. Percepción del bahiense
Full text linkLa contaminación urbana del aire es una de las principales preocupaciones alrededor del mundo, tanto en países desarrollados como en vías de desarrollo. El crecimiento de la población urbana y el incremento del volumen de tránsito motorizado en las ciudades, ha provocado una severa contaminación del aire que afecta el medio ambiente y la salud humana. Según la Organización Mundial de la Salud, los efectos de la contaminación del aire sobre la salud de las personas son serios, tal es así que un tercio de las muertes producidas por accidentes cerebrovasculares, cáncer de pulmón y enfermedades del corazón se deben a la contaminación del aire. Los contaminantes responsables por el deterioro de la calidad de aire urbana son los óxidos de nitrógeno, dióxido de azufre, monóxido de carbono, material particulado y los compuestos orgánicos volátiles. También deben considerarse la suspensión del polvo de las calles, debido al movimiento del tránsito, así como la utilización de neumáticos y frenos son fuentes significativas del incremento de concentración de material particulado en áreas urbanas. En este trabajo se presenta la problemática de la ciudad de Bahía Blanca, mostrando datos actualizados del parque automotor y su tendencia desde 2003. También se muestran los resultados de una encuesta ciudadana realizada por nuestro grupo sobre mas de 300 encuestados acerca de la percepción de la contaminación urbana y la relación con afecciones de vías respiratorias y piel.Fil: Grassi, Yamila Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. Universidad Nacional del Sur; ArgentinaFil: Brignole, Nélida Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. Universidad Nacional del Sur. Departamento de Ciencias e Ingeniería de la Computación; ArgentinaFil: Diaz, Monica Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina. Universidad Nacional del Sur. Departamento de Ingeniería Química; ArgentinaXXXII Congreso Argentino de QuímicaCiudad Autónoma de Buenos AiresArgentinaAsociación Química Argentin
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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