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Simultaneous application of membrane ultrafiltration, activated carbon adsorption, and ultrasound irradiation for fouling control in secondary wastewater treatment
No full textArtificial neural network in the measurement of environmental odours by e-nose
No full textOdour measurement plays a crucial role in environmental odour management. Continuous odour measurement systems are promoted to keep the situation always under control, such as being able to adopt the most suitable mitigation measures in real time to avoid odour complaints and impacts. Electronic Nose (eNose) represents currently the instrument of having the highest future developing potential to guarantee continuous odour measurements. To use an eNose, a training phase is however mandatory, which has the scope to create the Odour Monitoring Model (OMM) that is able to identify the presence of odour, the different odour classes and the quantification of the odorous stimuly. Statistical or biological inspired measurement techniques are applied to create the optimum OMM. The study presents and discusses the elaboration of an Artificial Neural Network (ANN) technique to recognize environmental odour with eNose. The proposed system was architected on a feed-forward neural network with Bayesian Regularization algorithm using Matlab R2017a software. The elaborated ANN was tested and validated using the seedOA eNose, realized by the Sanitary Environmental Engineering Division (SEED) of the Department of Civil Engineering of the University of Salerno (Italy). Tests were carried out analyzing odour samples collected at a large Wastewater Treatment Plant (WWTP). The comparison between the Odour Monitoring Model (OMM) elaborated through the proposed ANN system and the traditional statistical techniques, such as the Partial Least Square (PLS) and the Linear Discriminant Analysis (LDA), is also discussed. Results shown the efficiency of the elaborated ANN to identify the different odour classes and predict the odour concentration in terms of OUm-3. The artificial neural network shows smaller Root Mean Squared Errors (RMSE) and greater coefficient of determination (R2) as compared to the traditional statistical methods. The main advantages of neural networks are their adaptability in terms of learning, self-organization, training and noise-tolerance
Environmental odour management by artificial neural network – A review
No full textUnwanted odour emissions are considered air pollutants that may cause detrimental impacts to the environment as well as an indicator of unhealthy air to the affected individuals resulting in annoyance and health related issues. These pollutants are challenging to handle due to their invisibility to the naked eye and can only be felt by the human olfactory stimuli. A strategy to address this issue is by introducing an intelligent processing system to odour monitoring instrument such as artificial neural network to achieve a robust result. In this paper, a review on the application of artificial neural network for the management of environmental odours is presented. The principal factors in developing an optimum artificial neural network were identified as elements, structure and learning algorithms. The management of environmental odour has been distinguished into four aspects such as measurement, characterization, control and treatment and continuous monitoring. For each aspect, the performance of the neural network is critically evaluated emphasizing the strengths and weaknesses. This work aims to address the scarcity of information by addressing the gaps from existing studies in terms of the selection of the most suitable configuration, the benefits and consequences. Adopting this technique could provide a new avenue in the management of environmental odours through the use of a powerful mathematical computing tool for a more efficient and reliable outcome
CONTROLLO DI CONTAMINANTI EMERGENTI NELLE ACQUE REFLUE MEDIANTE ULTRAFILTRAZIONE MIGLIORATA CON ULTRASUONI
No full textIl riscontro della presenza nelle acque naturali di composti farmaceutici, anche se a basse concentrazioni, ha recentemente portato ad una crescente consapevolezza del loro potenziale pericolo per la salute. L’inadeguatezza dei processi convenzionali alla completa rimozione di tali contaminanti, rende opportuna la sperimentazione di processi di trattamento avanzati in grado di ottenere un’efficienza di rimozione di tali contaminanti significativa prima dello sversamento dei reflui nel corpo idrico ricettore o del loro riutilizzo. Nel presente studio, è stato investigato un processo ibrido chiamato USAMe®, che combina ultrafiltrazione su membrana, adsorbimento con carbone attivo ed ultrasuoni, al fine di valutare la sua influenza sulla rimozione dei contaminanti emergenti. Sono stati scelti come contaminanti target l’amoxicillina, la carbamazepina ed il diclofenac, in quanto maggiormente diffusi e per i rischi ambientali che essi comportano. L’indagine è stata focalizzata sui processi singoli e sulla loro combinazione. È stata, altresì, valutata l’influenza della dose di carbone attivo e della frequenza ultrasonica. I risultati ottenuti hanno mostrato come la combinazione di adsorbimento con ultrasuoni è in grado di migliorare significativamente la rimozione di tali contaminanti dalle acque reflue con una rimozione quasi completa nel processo USAMe®, evidenziando la sua potenziale applicazione come un processo di trattamento avanzato
Combined application of membrane ultrafiltration, adsorption, and ultrasound irradiation for the removal of pharmaceutical compounds from real wastewater
No full textThe presence of emerging contaminants (ECs) in water resources has raised a great concern in the last decades due to their persistence in the environment and their chronic toxicological and endocrine disrupting effects on terrestrial and aquatic organisms. Thus, advanced treatment methods are necessary for the removal of these
contaminants before wastewater reuse or disposal into aquatic ecosystem. In the present study, the hybrid process USAMe®, which combines ultrasound irradiation (US),
adsorption (A) and membrane filtration (Me), was investigated for the removal of ECs from real wastewater. Three pharmaceutical compounds - diclofenac (DCF),
carbamazepine (CBZ), and amoxicillin (AMX), were chosen for this study to represent highly consumed and frequently detected pharmaceuticals in the aquatic environment. All three pharmaceuticals were spiked into real wastewater at two concentrations of 10 ppm and 100 ppb. Membrane ultrafiltration and its combination with US (USMe) or adsorption (AMe) were also studied as control tests. The results obtained showed improved pharmaceutical removals in the membrane ultrafiltration process whenever an auxiliary treatment was employed. The degree of pharmaceutical removal was achieved in the order: Me<USMe<AMe<USAMe®. The USAMe® process applied to real wastewater successfully removed the target ECs, displaying its potential as an advanced method for wastewater treatment
Enhanced ozonation of selected pharmaceutical compounds by sonolysis
No full textIn search of new options to achieve removal of pharmaceuticals in the environment, combined ultrasound and ozonation has become a focus of intense investigation for wastewater treatment. In this study, three pharmaceuticals were selected as model compounds for degradation experiments: diclofenac (DCF), sulfamethoxazole (SMX) and carbamazepine (CBZ). Comparison of the degradation rates for both ozonation and combined ultrasound/ozonation treatments was performed on single synthetic solutions as well as on a mixture of the selected pharmaceuticals, under different experimental conditions. For single synthetic solutions, the efficiency removal for ozonation reached 73%, 51% and 59% after 40 min for DCF, SMX and CBZ, respectively. Comparable results were obtained for pharmaceuticals in mixture. However, the combined ultrasound/ozone treatment was found to increase degradation efficiencies for both DCF and SMX single solutions up to 94% and 61%, respectively, whereas lower removal yields, up to 56%, was noted for CBZ. Likewise, when the combined treatment was applied to the mixture, relatively low removal efficiencies was found for CBZ (44%) and 90% degradation yield was achieved for DCF
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Variations on the Author
Get PDF“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
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