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581.
Pires JC Gonçalves B Azevedo FG Carneiro AP Rego N Assembleia AJ Lima JF Silva PA Alves C Martins FG 《Environmental science and pollution research international》2012,19(8):3228-3234
Introduction
This study proposes three methodologies to define artificial neural network models through genetic algorithms (GAs) to predict the next-day hourly average surface ozone (O3) concentrations. GAs were applied to define the activation function in hidden layer and the number of hidden neurons.Methods
Two of the methodologies define threshold models, which assume that the behaviour of the dependent variable (O3 concentrations) changes when it enters in a different regime (two and four regimes were considered in this study). The change from one regime to another depends on a specific value (threshold value) of an explanatory variable (threshold variable), which is also defined by GAs. The predictor variables were the hourly average concentrations of carbon monoxide (CO), nitrogen oxide, nitrogen dioxide (NO2), and O3 (recorded in the previous day at an urban site with traffic influence) and also meteorological data (hourly averages of temperature, solar radiation, relative humidity and wind speed). The study was performed for the period from May to August 2004.Results and discussion
Several models were achieved and only the best model of each methodology was analysed. In threshold models, the variables selected by GAs to define the O3 regimes were temperature, CO and NO2 concentrations, due to their importance in O3 chemistry in an urban atmosphere.Conclusion
In the prediction of O3 concentrations, the threshold model that considers two regimes was the one that fitted the data most efficiently. 相似文献582.
Fulper CR Kishan S Baldauf RW Sabisch M Warila J Fujit EM Scarbro C Crews WS Snow R Gabele P Santos R Tierney E Cantrell B 《Journal of the Air & Waste Management Association (1995)》2010,60(11):1376-1387
Mobile sources significantly contribute to ambient concentrations of airborne particulate matter (PM). Source apportionment studies for PM10 (PM < or = 10 microm in aerodynamic diameter) and PM2.5 (PM < or = 2.5 microm in aerodynamic diameter) indicate that mobile sources can be responsible for over half of the ambient PM measured in an urban area. Recent source apportionment studies attempted to differentiate between contributions from gasoline and diesel motor vehicle combustion. Several source apportionment studies conducted in the United States suggested that gasoline combustion from mobile sources contributed more to ambient PM than diesel combustion. However, existing emission inventories for the United States indicated that diesels contribute more than gasoline vehicles to ambient PM concentrations. A comprehensive testing program was initiated in the Kansas City metropolitan area to measure PM emissions in the light-duty, gasoline-powered, on-road mobile source fleet to provide data for PM inventory and emissions modeling. The vehicle recruitment design produced a sample that could represent the regional fleet, and by extension, the national fleet. All vehicles were recruited from a stratified sample on the basis of vehicle class (car, truck) and model-year group. The pool of available vehicles was drawn primarily from a sample of vehicle owners designed to represent the selected demographic and geographic characteristics of the Kansas City population. Emissions testing utilized a portable, light-duty chassis dynamometer with vehicles tested using the LA-92 driving cycle, on-board emissions measurement systems, and remote sensing devices. Particulate mass emissions were the focus of the study, with continuous and integrated samples collected. In addition, sample analyses included criteria gases (carbon monoxide, carbon dioxide, nitric oxide/nitrogen dioxide, hydrocarbons), air toxics (speciated volatile organic compounds), and PM constituents (elemental/organic carbon, metals, semi-volatile organic compounds). Results indicated that PM emissions from the in-use fleet varied by up to 3 orders of magnitude, with emissions generally increasing for older model-year vehicles. The study also identified a strong influence of ambient temperature on vehicle PM mass emissions, with rates increasing with decreasing temperatures. 相似文献
583.
Heitor Evangelista Juan Maldonado Elaine A. dos Santos Ricardo H.M. Godoi Carlos A.E. Garcia Virginia M.T. Garcia Erling Jonhson Kenya Dias da Cunha Carlos Barros Leite René Van Grieken Katleen Van Meel Yaroslava Makarovska Diego M. Gaiero 《Atmospheric environment (Oxford, England : 1994)》2010,44(5):703-712
Iron (Fe) and other trace elements such as Zn, Mn, Ni and Cu are known as key-factors in marine biogeochemical cycles. It is believed that ocean primary productivity blooms in iron deficient regions can be triggered by iron in aeolian dust. Up to now, scarce aerosol elemental composition, based on measurements over sea at the Western South Atlantic (WSA), exist. An association between the Patagonian semi-desert dust/Fe and chlorophyll-a variability at the Argentinean continental shelf is essentially inferred from models. We present here experimental data of Fe enriched aerosols over the WSA between latitudes 22°S–62°S, during 4 oceanographic campaigns between 2002 and 2005. These data allowed inferring the atmospheric Fe flux onto different latitudinal bands which varied from 30.4 to 1688 nmolFe m?2 day?1 (October 29th–November 15th, 2003); 5.83–1586 nmolFe m?2 day?1 (February 15th–March 6th, 2004) and 4.73–586 nmolFe m?2 day?1(October 21st–November 5th, 2005). 相似文献
584.
C.A. Alves C. Gonçalves M. Evtyugina C.A. Pio F. Mirante H. Puxbaum 《Atmospheric environment (Oxford, England : 1994)》2010,44(23):2750-2759
Fine (PM2.5) and coarse (PM2.5–10) smoke particles from controlled biomass burnings of a shrub-dominated forest in Lousã Mountain, Portugal, enabled the quantification by chromatographic techniques of several molecular tracers for the combustion of Mediterranean forest ecosystems, which could be conducive to source apportionment studies. The major organic components in the smoke samples were pyrolysates of vegetation cuticles, mainly comprising steradienes and sterol derivatives, carbohydrates from the breakdown of cellulose, aliphatic lipids from vegetation waxes and methoxyphenols from the lignin thermal degradation. Most of these compounds are chiefly found in fine particles. Polycyclic aromatic hydrocarbons (PAH) were also present as minor constituents. Anhydrosugar and PAH molecular diagnostic ratios were applied as source assignment tools. Some biomarkers are reported for the first time in biomass burning smoke. 相似文献
585.
Costa Maria Angélica Martins da Silva Bruno Menezes de Almeida Sâmilla Gabriella Coelho Felizardo Marcos Paulo Costa Ana Flávia Martins Cardoso Arnaldo Alves Dussán Kelly Johana 《Environmental science and pollution research international》2023,30(4):8835-8852
Environmental Science and Pollution Research - Energy demand has increased worldwide, and biomass burning is one of the solutions most used by industries, especially in countries that have a great... 相似文献
586.
Araújo Leylia K. F. Albuquerque Allan A. Ramos Weslley C. O. Santos Alef T. Carvalho Sandra H. V. Soletti João I. Bispo Mozart D. 《Environment, Development and Sustainability》2021,23(8):11732-11750
Environment, Development and Sustainability - The activated biochar is a carbonaceous material obtained from thermal degradation of biomass with high adsorption potential. On the other hand, the... 相似文献
587.
de Oliveira Maria Rayane Correia de Lima Silva Maria Gabriely Alcântara Isabel Sousa Filho Jaime Ribeiro Tintino Cícera Datiane de Morais Oliveira Magalhães Francisco Ernani Alves Martins Anita Oliveira Brito Pereira Bezerra Pessoa Renata Torres Duarte Antonia Eliene da Costa José Galberto Martins de Lima Sidney Gonçalo Coutinho Henrique Douglas Melo Capasso Raffaele de Menezes Irwin Rose Alencar 《Environment, Development and Sustainability》2021,23(10):14958-14981
Environment, Development and Sustainability - This work aimed to analyze the chemical composition and evaluate the anti-inflammatory and antinociceptive properties of the essential oil obtained... 相似文献
588.
Adeyemi Joseph A. Gallimberti Matheus Olise Christian C. Rocha Bruno Alves Adedire Chrs O. Barbosa Jr Fernando 《Environmental science and pollution research international》2020,27(30):37645-37649
Environmental Science and Pollution Research - Bisphenol A (BPA) is a high production volume chemical that has wide industrial applications, especially as a color developer in thermal papers. The... 相似文献
589.
Melo Mikhael Rangel de Souza Dias Nildo da Silva de Medeiros Igor José Nascimento Travassos Kaline Dantas Miranda Neyton de Oliveira Gurgel Marcelo Tavares Lemos Neto Hozano de Souza Fernandes Cleyton dos Santos 《Environmental science and pollution research international》2020,27(31):38537-38544
Environmental Science and Pollution Research - In a context of scarcity of good quality water, reuse is a mandatory practice to increase water availability, thus allowing the exploitation of more... 相似文献
590.
Rita Santos Ronald Wennersten Eduardo B.L. Oliva Walter Leal Filho 《Journal of environmental management》2009,90(12):3708
The competitiveness, in terms of macro and micro levels of an enterprise, is often dictated by its capacity to innovate, ability to respond to the needs of the market, and resilience to challenges from competition. This paper reviews the literature on the adaptation of research and development (R&D) units in subsidiaries of multinational corporations. It focuses mainly on the impact of the technological dynamic on sustainability performance of the Brazilian subsidiary of the Swedish multinational Ericsson. Through a conceptual framework, it explores information and communication technologies (ICT) towards a transversal and comprehensive vision of levels of innovation and sustainability. 相似文献