scholarly journals Modeling and Characterization of Traffic Flows in Urban Environments

Sensors ◽  
2018 ◽  
Vol 18 (7) ◽  
pp. 2020 ◽  
Author(s):  
Jorge Zambrano-Martinez ◽  
Carlos Calafate ◽  
David Soler ◽  
Juan-Carlos Cano ◽  
Pietro Manzoni
Keyword(s):  
Urban Environments ◽  
Traffic Flows

Representative Time Series Fractal Analysis of the Traffic Flows of a Dedicated High-Speed Link

2021 ◽  
Author(s):  
Ginno Millan ◽  
manuel vargas ◽  
Guillermo Fuertes
Keyword(s):  
Time Series ◽  
Traffic Flow ◽  
Long Range ◽  
Computer Networks ◽  
Fractal Analysis ◽  
High Speed ◽  
Long Range Dependence ◽  
Traffic Flows ◽  
Speed Computer

Fractal behavior and long-range dependence are widely observed in measurements and characterization of traffic flow in high-speed computer networks of different technologies and coverage levels. This paper presents the results obtained when applying fractal analysis techniques on a time series obtained from traffic captures coming from an application server connected to the internet through a high-speed link. The results obtained show that traffic flow in the dedicated high-speed network link exhibited fractal behavior since the Hurst exponent was in the range of 0.5, 1, the fractal dimension between 1, 1.5, and the correlation coefficient between -0.5, 0. Based on these results, it is ideal to characterize both the singularities of the fractal traffic and its impulsiveness during a fractal analysis of temporal scales. Finally, based on the results of the time series analyzes, the fact that the traffic flows of current computer networks exhibited fractal behavior with a long-range dependence was reaffirmed.

Trajectory Clustering and Classification for Characterization of Air Traffic Flows

2016 ◽  
Author(s):  
Mayara Conde Rocha Murca ◽  
Richard DeLaura ◽  
R John Hansman ◽  
Richard Jordan ◽  
Tom Reynolds ◽  
...  
Keyword(s):  
Air Traffic ◽  
Traffic Flows ◽  
Trajectory Clustering ◽  
Clustering And Classification

scholarly journals Seasonal Changes of the Airborne Microbiome in a Large Urban Area

2020 ◽  
Author(s):  
Andrés Núñez ◽  
Diego A Moreno ◽  
Ana M García ◽  
Raul Guantes
Keyword(s):  
Disease Outbreaks ◽  
Urban Environments ◽  
Minor Role ◽  
Near Surface ◽  
Surface Atmosphere ◽  
Ecological Importance ◽  
Bacteria And Fungi ◽  
A Minor

Abstract Background Compared to soil or aquatic ecosystems, the atmosphere is still an underexplored environment for microbial diversity. Besides its ecological importance, the spatial and temporal characterization of aerosolized microorganisms is relevant for understanding allergy and disease outbreaks, especially in highly populated cities. Results In this study, we surveyed the composition, variability and sources of microbes (bacteria and fungi) in the near surface atmosphere of a highly populated area, spanning ~ 4,000 Km 2 around the city center of Madrid (Spain), in different seasonal periods along two years. We found a core of abundant bacterial genera robust across space and time, most of soil origin, while fungi were more sensitive to environmental conditions. Microbial communities showed clear seasonal patterns driven by variability of environmental factors, mainly temperature and accumulated rain, while local sources played a minor role. We also identified taxa in both kingdoms characteristic of seasonal periods, but not of specific sampling sites or plant coverage. Conclusions The present study suggests that the near surface atmosphere of urban environments constitutes a stable ecosystem, with a relatively homogenous composition, modulated by climatic variations. As such, it contributes to our understanding of the long-term changes associated to the human exposome in the air of highly populated areas.

scholarly journals EFICIÊNCIA DE GONGOCOMPOSTOS OBTIDOS A PARTIR DE DIFERENTES RESÍDUOS VEGETAIS E SISTEMAS DE PRODUÇÃO NO DESENVOLVIMENTO DE MUDAS DE ALFACE

Nativa ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 147-156
Author(s):  
Luiz Fernando de Sousa Antunes ◽  
Rafael Girelli de Souza ◽  
Julia de Lima Krahenbuhl ◽  
Guilherme Rocha Dias ◽  
Dione Galvão da Silva ◽  
...  
Keyword(s):  
Production Systems ◽  
Chemical Properties ◽  
Urban Environments ◽  
Expanded Polystyrene ◽  
Organic Substrates ◽  
Rural And Urban ◽  
Grand Rapids ◽  
Lettuce Cultivar ◽  
And Chemical Properties

O uso do gongocomposto pode contribuir para suprir a crescente demanda por substratos destinados à produção de mudas de hortaliças em ambientes rurais e urbanos. Nesse contexto, objetivou-se com este trabalho verificar a eficiência dos gongocompostos obtidos em dois diferentes sistemas de produção, situados em regiões de ambientes distintos (estados do RJ e SP) e com a utilização de resíduos orgânicos e espécies de diplópodes diferentes entre si, na produção de mudas de alface. Inicialmente foi realizada uma minuciosa caracterização dos substratos avaliados, caracterizando as propriedades físicas, físico-químicas e químicas. O desempenho dos diferentes substratos na produção de mudas de alface foi avaliado por meio da semeadura de alface crespa cultivar Grand Rapids em bandejas de poliestireno expandido de 200 células. As mudas foram avaliadas aos 30 dias após a semeadura. Os gongocompostos produzidos no estado do RJ e SP apresentam diferenças em suas propriedades físicas, físico-químicas e químicas. No entanto, ambos produziram mudas de alface com qualidade semelhante, cujos parâmetros fitotécnicos foram superiores ao substrato comercial. Pode-se concluir que ambos os gongocompostos são eficientes como substrato na produção de mudas de alface, os quais podem ser produzidos em ambientes rurais e urbanos, atendendo à necessidade atual por insumos agrícolas sustentáveis. Palavras-chave: resíduos agrícolas e urbanos; diplópodes; gongocompostagem; substratos orgânicos; horticultura.   Efficiency of millicomposts obtained from different vegetable residues and production systems in the development of lettuce seedlings   ABSTRACT: The use of millicompost can contribute to the growing demand for substrates for vegetable seedling production in rural and urban environments. In this context, the objective of this work was to verify the efficiency of millicomposts obtained in two different production systems, located in regions of different environments (states of RJ and SP) and with the use of organic residues and different species of diplopods, in the production of lettuce seedlings. Initially, a thorough characterization of the evaluated substrates was performed, characterizing the physical, physicochemical and chemical properties. The performance of different substrates in the production of lettuce seedlings was evaluated by sowing crisp lettuce cultivar Grand Rapids in 200-cell expanded polystyrene trays. The seedlings were evaluated at 30 days after sowing. Millicomposts produced in the states of RJ and SP show differences in their physical, physicochemical and chemical properties. However, both produced similar quality lettuce seedlings, whose phytotechnical parameters were superior to the commercial substrate. It can be concluded that both millicomposts are efficient as a substrate in the production of lettuce seedlings, which can be produced in rural and urban environments, meeting the current need for sustainable agricultural inputs. Keywords: agricultural and urban wastes; diplopods; millicomposting; organic substrates; horticulture.

scholarly journals AN ENERGY-BASED APPROACH FOR DETECTION AND CHARACTERIZATION OF SUBTLE ENTITIES WITHIN LASER SCANNING POINT-CLOUDS

2016 ◽  
Vol XLI-B3 ◽  
pp. 167-171
Author(s):  
Reuma Arav ◽  
Sagi Filin
Keyword(s):  
Laser Scanning ◽  
Optimization Problem ◽  
Point Clouds ◽  
Urban Environments ◽  
Natural Environments ◽  
Detection Scheme ◽  
Airborne Laser ◽  
The Common ◽  
Geomorphological Features

Airborne laser scans present an optimal tool to describe geomorphological features in natural environments. However, a challenge arises in the detection of such phenomena, as they are embedded in the topography, tend to blend into their surroundings and leave only a subtle signature within the data. Most object-recognition studies address mainly urban environments and follow a general pipeline where the data are partitioned into segments with uniform properties. These approaches are restricted to man-made domain and are capable to handle limited features that answer a well-defined geometric form. As natural environments present a more complex set of features, the common interpretation of the data is still manual at large. In this paper, we propose a data-aware detection scheme, unbound to specific domains or shapes. We define the recognition question as an energy optimization problem, solved by variational means. Our approach, based on the level-set method, characterizes geometrically local surfaces within the data, and uses these characteristics as potential field for minimization. The main advantage here is that it allows topological changes of the evolving curves, such as merging and breaking. We demonstrate the proposed methodology on the detection of collapse sinkholes.

scholarly journals Method of measuring the acoustic characteristics of traffic flows in urban environments

2020 ◽  
Vol 78 (4) ◽  
pp. 273-279
Keyword(s):  
Traffic Noise ◽  
Urban Environments ◽  
Traffic Flows ◽  
Noise Levels ◽  
Acoustic Characteristics ◽  
Low Frequencies ◽  
High Frequencies ◽  
Medical Institutions

When examining doctors ' workplaces, it was found that traffic noise inside the premises exceeds sanitary standards. For medical institutions, the sanitary standards are 50 dBA, and for fullscale measurements, they were 60-63 dBA. Traffic noise levels have a maximum at low frequencies (31.5 Hz) and a minimum at high frequencies (16,000 Hz).

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