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1.
Environ Pollut ; 286: 117489, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119860

RESUMO

The Menor sea is a coastal lagoon declared by the European Union as a sensitive area to eutrophication due to human activities. To control the deterioration of its water quality, it is necessary to monitor some parameters such as chlorophyll-a (chl-a), which indicates phytoplankton biomass in the water. In the study area, current efforts focus on in-situ measurements to estimate chl-a by means of a few permanent stations and seasonal oceanographic campaigns, however they are expensive and time consuming. In this work, we proposed a machine learning approach based on Sentinel-2 data to estimate chl-a content on the upper part of the water column. Random forest (rf), support vector machine (svmRadial), Artificial Neural Network (ANN) and Deep Neural Network (DNN) algorithms were utilized under three feature selection scenarios, and several spectral indices were used in combination with Sentinel 2 bands. Rf, svmRadial and DNN performed better when all the available predictors were included in the models (RMSE = 0.82, 0.82 and 1.76 mg/m3 respectively), whereas ANN achieved better results under scenario c (principal components). Our results demonstrate the possibility to estimate chl-a concentration in a cost-effective manner and thereby provide near-real time information to monitor the water quality of the Menor sea, what can be of great interest for local authorities, tourism and fishing industry.


Assuntos
Monitoramento Ambiental , Qualidade da Água , Clorofila/análise , Clorofila A/análise , Humanos , Aprendizado de Máquina , Espanha
2.
J Gerontol Soc Work ; 60(6-7): 535-552, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28463072

RESUMO

In Portugal, Spain, and South Africa, there has been a noted anti-neoliberal resistance, marked by the significant participation of the older generation in protest movements. Changing demographics, the global financial crisis, unemployment, poverty, and the reliance of the family nucleus on the pensioner, coupled with neoliberal and austerity-based reductions to welfare programs, pensions, health, and social care, has caused the "silver revolution." As a population group that is often considered to be less politically active and robust members of society, such resistance is a noteworthy moment in society that needs to be considered and responded to.


Assuntos
Dissidências e Disputas , Recessão Econômica/tendências , Pensões/estatística & dados numéricos , Política , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Feminino , Direitos Humanos/tendências , Humanos , Masculino , Políticas , Portugal , África do Sul , Espanha
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