33 research outputs found
Optical particle counter data collected in two inhabited sites close to an industrial hot spot during a three months survey
Data on this paper describe the monitoring of different size ranges of particulate matter on dwellings positioned close to an integral cycle steel plant. Data were collected by eight channel (PM0.3, PM0.5, PM0.7, PM1, PM2, PM3, PM5, PM10) optical particle counters positioned in two sites. The data were recorded as counts-per-minute for every size channel in a three months survey from June to September 2015. Basic statistical elaboration and boxplot graphs as well as raw data are included
Self-organizing map algorithm as a tool for analysis, visualization and interpretation of electronic nose high dimensional raw data
Electronic noses used for outdoor ambient air characterization to assess odor impacts on population can produce large datasets since usually the sampling is conducted with high frequency (e.g. data per minute) for periods that can reach several months, with a number of sensors that ranges usually from four-six as a minimum, up to above thirty. The environmental analyst has thus to deal with large datasets (millions of data) that have to be properly elaborated for obtaining meaningful interpretation of the instrumental signals. A recent review questioned the capability of some classic statistical elaboration tools for application to e-noses, highlighting how very few in field application are present in scientific literature. In the present work we describe: (i) the use of Self-Organizing Map (SOM) algorithm as a tool for analysis and visualization of e-nose raw data collected at a receptor site near a bio-waste composting facility; (ii) a second level clusterization using k-means clustering algorithm to identify "air types" that can be detected at the receptor and (iii) the use of e-nose data related to the plant odour sources as well as odour measurements of ambient air collected at the receptor site, to classify the air types. Eventually we evaluate the frequency and duration of the air type/s identified as malodorous
Testing performances of a newly designed olfactometer
Dynamic dilution olfactometry as regulated by EN 13725 requires instrumentation of adequate technology and in order to spread the use of Dynamic Olfactometry high usability of the device is a must. A new dynamic dilution olfactometer has been designed and manufactured after the experience gained in previous prototype development and performance studies as well as from experimental applications. Materials have been selected in order to be compliant with the expected next-to-come updates of the EN13725 technical norm and checks on pneumatic steps required by the odour concentration analysis procedure have been implemented.
In order to generate specific dilutions in a wide range, a high precision stepper motor is used, instead of the more common calibrated orifices. The instrument comes with option of incrementing dilution with a factor of 1a2 (instead of more usual 2), so to increase resolution of the odour measurements. The consumption of neutral compressed air has been highly reduced in comparison with previous prototypes. The new features of the instrument as well as the available dilution steps will be presented. A careful check of accuracy and operative speed at high dilutions has been performed. Standard n-butanol, and samples from ambient air collected in
close proximity from odour emitting sources have been collected for testing the olfactometer and the panel response. A market top instrument has been considered for sake of comparison
La combustione e le sorgenti antropiche
Pensato durante il Convegno PM2008 (Bari, 6-8 ottobre 2008), organizzato dalla IAS (Societ\ue0 italiana di Aerosol) e dalla SCI (Societ\ue0 Chimica Italiana) in collaborazione con diversi partner , \ue8 stato pubblicato da Villaggio Globale il volume \u201cParticelle in atmosfera - Conosciamole meglio\u201d, a cura di Gianluigi de Gennaro (Universit\ue0 degli Studi di Bari) e Stefania Petraccone (Villaggio Globale).
Nel libro, la descrizione in capitoli di una tematica di grande attualit\ue0, il particolato atmosferico, attraverso i contributi degli scienziati italiani che si occupano della Scienza degli Aerosol, proposti con un linguaggio comprensibile anche dai non addetti ai lavori.
Introduzione a cura di Luigi Campanella, presidente SCI - Societ\ue0 Chimica Italiana
\u201c\u2026si capisce dai temi che sarebbe facile decadere nel nozionismo. I nostri autori non lo fanno, anzi al contrario cercano di evitarlo riconducendosi sempre ad aspetti con i quali si confrontano tutti i giorni i normali cittadini\u201d
Prefazione a cura di Franco Prodi, presidente IAS - Societ\ue0 Italiana di Aerosol
\u201c...l\u2019idea di parlarne in modo cos\uec semplice \ue8 che si possa portare tanti giovani alla curiosit\ue0, prima, e ad una vocazione scientifica poi, talmente forte da impegnarli con una scelta di vita professionale\u201d
I capitoli
1. Caratteristiche chimico fisiche
2. Le sorgenti
3. Il monitoraggio
4. Effetti degli aerosol su scala globale
5. PM e Salute
6. Sistemi per il supporto al decisore
7. Aspetti normativ
Extracting knowledge from hybrid instrumental environmental odour monitoring systems: Self organizing maps, data fusion and supervised kohonen networks for prediction
High frequency multi-sensor patterns for instrumental odor monitoring in urban areas close to industrial districts requires adequate analytical strategies, hardware and effective data analysis and control procedures. An approach linking data analysis tools is presented based on unsupervised identification of recurrent patterns from data produced by hybrid instrumental odour monitoring systems. A self-organizing map is built and clustered in order to identify air typologies at a e-nose site; they are interpreted thanks to data fusion of sensorial data from citizen complaints, olfactometric measures, air pollutants and meteorological data. A supervised Kohonen network generates quantitative relationships between multisensor patterns and sparse olfatometric measures on air samples timely collected after complaints or instrumental threshold exceedance, allowing high frequency estimates of odour concentrations
Indagine dell'esposizione a polveri ed inquinanti atmosferici di lavoratori outdoor nell'area di Muggia (Trieste)
L\u2019inquinamento urbano di origine veicolare,
domestico ed industriale espone varie categorie di lavoratori
a molteplici agenti chimici dannosi per la salute per cui negli
ultimi anni sono state effettuate diverse indagini su vigili urbani,
taxisti, guidatori di autobus, poliziotti, edicolanti, benzinai e sulla
popolazione generale per una stima dell\u2019esposizione ai principali
contaminanti, soprattutto IPA e benzene.
Obiettivo. Definire una specifica strategia di campionamento
per ottenere delle basi sperimentali sull\u2019esposizione potenziale
della popolazione a polveri sospese nell\u2019area comunale
di Muggia (TS).
Materiali e metodi. \uc8 stato analizzato un campione di 14 vigili
urbani occupazionalmente esposti che svolgono la loro
professione prevalentemente \u201cin strada\u201d e un campione di
13 amministrativi comunali (controllo) che svolgono la loro
professione, nelle stesse ore, in ambiente confinato (ufficio).
L\u2019esposizione \ue8 stata misurata mediante campionatori
personali e campionatori ambientali ad alto volume. Si sono
inoltre determinati i livelli di 1-idrossipirene e creatinina nei
campioni di urine prelevati da tutti i soggetti in esame.
Risultati. L\u2019analisi degli IPA ha fornito rapporti diagnostici
per l\u2019individuazione delle sorgenti inquinanti. In generale
i valori di BaP ottenuti si mantengono al di sotto del limite
previsto, con buon accordo tra il monitoraggio ambientale e
quello personale. Il dosaggio dell\u20191-OH pirene rimane entro
il valore di fondo (0.089 \u3bcmoli/mole di creatinina) per il
personale amministrativo, mentre la maggior parte dei dati
relativi ai vigili, pur ampiamente al di sotto del valore
di prudenza risultano superiori
Characterization of variability of air particulate matter size profiles recorded by optical particle counters near a complex emissive source by use of Self-Organizing Map algorithm
In the present study we propose the application of a procedure of data analysis based on the Self-Organizing Map algorithm and k-means clustering in series (1st level and 2nd level abstraction respectively) as a strategy to identify recurrent ambient air particulate matter (PM) size profiles starting from the elaboration of high frequency data recorded by an Optical Particle Counter (OPC). We tested the strategy on data deriving from a three months survey at a residential site in proximity to an integral cycle steel plant in Trieste (NE Italy). We were able to identify four clusters representing recurrent PM class profiles whose meaning has been interpreted and confirmed by correlation to \u201cexternal data\u201d, i.e. data not used to build the model, registered by other devices (meteorological and pollutant monitoring stations). The four clusters were found to be related to two different plant type of emissions (sources) and to two different site background profiles, respectively. The powerful visualization features of SOM map allowed to describe and characterize the variability of size distribution of PM in a concise form. The clustered SOM being built for one measuring station, proved to be helpful for the analysis of OPC data collected at another location close to the industrial plant. Moreover, occasional episodes of Saharan dusts could be identified as outliers with respect to local particulate and discussed in terms of size distribution. Eventually, by means of an animated graph, we propose a method to visualize the PM experimental data evolution during the day using the PM cluster profiles as a legend. \ua9 201
Positive matrix factorization on aerosol monitoring data in the chair production district of Friuli Venezia Giulia region: source identification and small scale heterogenehity
In order to assess the possible relevance on particulate composition of
emissions from an incinerator serving a furniture production district in
Manzano (Ud), two sampling sites were identified, respectively downwind
and upwind to the plant, by means of the CalPuff computational code (1) for
modeling the particulate dispersion, considering local orography and
meteorology. Two Hydra samplers from FAI Instruments were positioned at
the selected sites, allowing the collection of daily PM10 on quartz filters
between February and April 2010. Analytical determinations of OC, EC,
WSOC, WINSOC, TC, thirteen PAHs (including benzo[a]pyrene), Na+,
NH4
+, K+, Mg2+, Ca2+, Cl-, NO3
-, SO4
2-, levoglucosan (2), As, Cd, Ni, Pb
were performed. The PM10 concentration is very similar at the two sites,
located 3 km apart, but chemical composition is not perfectly overlapping.
A source apportionment study has been performed for the two sites,
pointing at the relevance of each source in each sampled day, by Positive
Matrix Factorization (3). An agricultural source (ammonia nitrate) was
identified, as well as biomass combustion, crustal/dust resuspension (Ca2+,
Pb/ Na+,Cl-) and sulfate sources. Unexpectedly, the factor associated to
biomass burning, related to EC, BaP, K and levoglucosan, is more relevant
at the site upwind from the considered incinerator. The contribution of
agricultural activities to the local aerosol is evident and it is highlighted by
the \u201cammonia nitrate\u201d factor but also by the presence of a herbicide in the
particulate matter (4), which is one hundred times higher at the downwind
site than upwind