Publications of Anne-Claude Romain
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See detailIdentification of several environmental odours with tin oxide sensor array : three years later
Romain, Anne-Claude ULiege; Nicolas, Jacques ULiege; Maternova, J.

Poster (2001)

The paper discusses the ability of recognition models to classify malodours in the environment three years after their calibration, with the same sources releasing odours. Two methodologies applicable ... [more ▼]

The paper discusses the ability of recognition models to classify malodours in the environment three years after their calibration, with the same sources releasing odours. Two methodologies applicable either in the lab or in the field are used. The effect of the long term drift of the sensors is highlighted on the results of principal component analysis and of discriminant function analysis. The paper examines also the applicability of some drift counteraction methods proposed in the literature. Handled with some care, a correction based on the drift direction in the principal components subspace should be applicable to the classification of real odorous sources in the field. [less ▲]

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See detailChemometrics methods for the identification and the monitoring of an odour in the environement with an electronic nose
Nicolas, Jacques ULiege; Romain, Anne-Claude ULiege; Maternova, J.

in Ramirez-Silva, Maria Theresa (Ed.) Sensors and chemometrics (2001)

The purpose of the paper is to briefly review some researches regarding the adaptation of the electronic nose principle to recognise some malodour sources in the environment, if possible directly in the ... [more ▼]

The purpose of the paper is to briefly review some researches regarding the adaptation of the electronic nose principle to recognise some malodour sources in the environment, if possible directly in the field, and to monitor the odour intensity continuously. Research aims at improving the portability and the user-friendliness of the instrument, together with testing what kind of signal may be used to monitor the odour. A laboratory-made electronic nose, constituted of an array of tin-oxide sensors, is used in different configurations. The ambient air is either sampled around environmental sources (landfill, urban waste composting facilities, …), or directly transferred into the sensor chamber in the field. Two main options are considered : firstly, identifying the source of odour in the background and among interfering odours and, secondly, when the malodour is recognised, trying to monitor it continuously in order, for example, to assess the nuisance or to control an odour abatement system. Chemometrics methods are generally used for both purposes. They provide quick answers and allow to evaluate the relationships between variables and between observations at a glance. They are applied on the sensor signals, eventually preprocessed by a suitable algorithm. Non-supervised analyses, such as Principal Component Analysis (PCA), provide basically a performance evaluation of the system during the development phase. On the contrary, supervised analyses, such as Discriminant Analysis (DA), or some Neural Networks algorithms are quite appropriate to make a reliable recognition in real time, when the system is developed. To predict the odour intensity, different techniques are tested : either using only one of the sensor elements, or applying different chemometrics techniques, such as Multilinear Regression (MLR) on the original measured sensor signals, Principal Component Regression (PCR), or Partial Least Squares regression (PLS). The latter seems to be the most adapted model for the intensity prediction. [less ▲]

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See detailMeasurement requirements for environmental monitoring : application of the electronic nose principle.
Nicolas, Jacques ULiege; Romain, Anne-Claude ULiege; Andre, Philippe ULiege

Conference (2000)

As regards environment, the information to be provided to the decision maker or to the manager must be clear, accurate, unambiguous, and ideally it should be the result of the aggregation of a great ... [more ▼]

As regards environment, the information to be provided to the decision maker or to the manager must be clear, accurate, unambiguous, and ideally it should be the result of the aggregation of a great number of data or parameters. For example, the person in charge of the security of a municipality must have at his disposal an information of the type "all or nothing" to be able to decide if the population must be evacuated in the event of a severe pollution. However, that very simple information should be the result of a calculation based on several time series of pollutant concentration values and of meteorological data. Even the farmer who wants to know if it is the right time to spread manure without affecting too much the environment must have a single information which should be the aggregation of some complex variables. The lecture presents the concept of some "integrated index", already used to assess the quality of the environment. For example, Organic Pollution Index combines 4 laboratory measurement values of pollutants in water to make a single index characterising the global pollution in a river. Some apparatus are able to compute the integrated index "on line" and to supply directly to the user the value of the medium quality. For example, the PMV index estimates globally the thermal comfort in a building from the on line measurement of 5 parameters. FUL has designed some "smart sensors" or "smart instrument" aiming at supplying such index. Two applications are presented. The first one concerns the measurement of soil quality by means of a porous sensor combining in a single index the measurement of temperature, salinity and water contents. But the lecture develops particularly a second application which exploits the principle of the "electronic nose" to assess, in a single "signature", the quality or the intensity of an environmental odour. Such instrument, equipped with an array of "non specific" gas sensors, should be able, after a suitable learning phase, to recognise the odour source and to monitor it continuously in the field. The instrument response is thus a "pattern", similar to an integrated index, directly related to the annoyance, as felt by neighbouring people. It gives thus an information which can be handled by a manager, and which is more rich than individual pollutant concentration values. FUL has tested such instrument in the environment. The results are promising : a first design of electronic nose was able to recognise 5 odorous sources in the environment, and a portable instrument has been used to monitor the odour around a landfill site. The same concept is now tested to appraise as a whole the indoor air quality in different buildings. [less ▲]

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See detailContrôle/commande de la réduction d'odeur générée par un Centre d'Enfouissement Technique
Nicolas, Jacques ULiege; wiertz, Véronique; Monticelli, David et al

Report (2000)

An instrument based on the "electronic nose" concept was developed with the aim of controlling an odour abatement technique, as the spraying of masking or neutralising agent, on a landfill area in Belgium ... [more ▼]

An instrument based on the "electronic nose" concept was developed with the aim of controlling an odour abatement technique, as the spraying of masking or neutralising agent, on a landfill area in Belgium. Models of odour recognition and of odour level prediction were developed and successfully validated in the field. Additionally to e-nose response, the influence of meteorological data was particularly studied. The project was conducted on a real size facility and in close collaboration with the manager of the facility. [less ▲]

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See detailChoice of a suitable E-nose output variable for the continuous monitoring of an odour in the environment
Nicolas, Jacques ULiege; Romain, Anne-Claude ULiege; Monticelli, D. et al

in Gardner, J.; Persaud, K. (Eds.) Electronic noses and olfaction 2000. Proceedings of abstracts ISOEN 2000. (2000)

An array of tin-oxide sensors is used to continuously monitor different odour emissions in the environment. The paper presents some issues aiming at improving the portability and the user-friendliness of ... [more ▼]

An array of tin-oxide sensors is used to continuously monitor different odour emissions in the environment. The paper presents some issues aiming at improving the portability and the user-friendliness of the instrument as well as testing what kind of signal may be used to monitor the odour "intensity". Main results are the following. The test of various pre-processing data algorithms pointed out that the use of pure reference air could be avoided, as long as the sensors are allowed to periodically regenerate in the presence of ambient air. Sensor array in static contact with ambient air could be sufficient for the on-line monitoring, but the use of a controlled gas flow system to transfer the odour from the source is better to avoid the influence of air movement on the heated sensors. The control of the temperature and the humidity of the gas and the thermo-regulation of the sensor chamber don't seem essential, even for outdoor operation. When trying to build a regression model linking the odour intensity to the sensor signals, Partial Least Square (PLS) model gives better results with respect to Multi Linear Regression or Principal Component regression models. For an application around a landfill area, where sensor signals are compared to the personal feeling of the operator in the field, PLS gives a percentage of 71% correct intensity prediction. [less ▲]

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See detailUsing the classification model of an electronic nose to assign unknown malodours to environmental sources and to monitor them continuously
Nicolas, Jacques ULiege; Romain, Anne-Claude ULiege; Wiertz, Véronique et al

in Sensors and Actuators. B, Chemical (2000), 69(3), 366-371

The paper provides some considerations resulting from measurements with electronic noses around real sources of malodour in the environment: compost facilities, printing houses, paint shops, waste water ... [more ▼]

The paper provides some considerations resulting from measurements with electronic noses around real sources of malodour in the environment: compost facilities, printing houses, paint shops, waste water treatment plants, rendering plants, settling ponds of sugar factories. The study aims at supplying the concrete information requested by the final user in the field: either a warning signal when the malodour level exceeds some given threshold value, the identification of the source of an odour detected on site, or on-line identification and monitoring of an odour in the field. Very simple instruments are used, either in the laboratory or directly in the field, with a home-made portable e-nose, based on tin oxide sensors. Even with such simple operating conditions, the classification results with DA and PCA are fairly good. The classification functions calibrated with the statistical procedure, on the basis of the learning phase, are used to recognise and to monitor a given malodour. This odour is sometimes mixed with other odorous interferences in the field. The observations reveal some features useful in the frame of the development of a field detector. [less ▲]

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See detailUse of a simple tin oxide sensor array to identify five malodours collected in the field
Romain, Anne-Claude ULiege; Nicolas, Jacques ULiege; Wiertz, Véronique et al

in Sensors and Actuators. B, Chemical (2000), 62(1), 73-79

A laboratory-made malodour sensing system including 12 commercial tin oxide gas sensors (Figaro Engineering) is used to identify five typical sources of olfactive annoyance: printing houses, paint shop in ... [more ▼]

A laboratory-made malodour sensing system including 12 commercial tin oxide gas sensors (Figaro Engineering) is used to identify five typical sources of olfactive annoyance: printing houses, paint shop in a coachbuilding, wastewater treatment plant, urban waste composting facilities and rendering plant. In this work, all the samples are collected in the field from real malodours in uncontrollable conditions. The ability of the system to predict the origin of unknowns odoriferous samples is investigated. The test of various pre-processing data algorithms shows that the best classification results are obtained with a parameter free of the sensor base-line. The differences in sensor responses among the five odours are shown by icon plots and confirmed by principal component analysis, which highlights four representative clusters. Classification models calibrated by discriminant analysis and artificial neural network are validated on unknowns samples. Chemical relationships between the sensors and the classification results proves that the recognition is not fortuitous. In spite of the influence of environmental parameters, results demonstrate the ability of a simple system to detect and identify typical olfactive annoyances. [less ▲]

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See detailUtilisation élémentaire d'un réseau de capteurs "SnO2" pour la reconnaissance d'odeurs environnementales
Nicolas, Jacques ULiege; Romain, Anne-Claude ULiege; Wiertz, Véronique et al

(1999, June)

Pouvoir identifier les mauvaises odeurs et les suivre en continu directement sur le terrain constituerait sans conteste un atout non négligeable pour un bon nombre d'études environnementales. Sur le ... [more ▼]

Pouvoir identifier les mauvaises odeurs et les suivre en continu directement sur le terrain constituerait sans conteste un atout non négligeable pour un bon nombre d'études environnementales. Sur le principe, un tel objectif semble correspondre parfaitement aux possibilités et à la souplesse d'un nez électronique. Cependant, si l'environnement est fréquemment cité parmi les applications possibles des nez électroniques, il faut reconnaître que les études visant la mesure des mauvaises odeurs sur le terrain restent très rares. La généralisation du concept du nez électronique au monitoring d'odeurs environnementales doit passer par la résolution d'un certain nombre de problèmes. La communication propose de mettre en évidence ces différentes limitations et problèmes. L'étude présentée pour illustrer ce propos est relative aux odeurs provenant de 5 sources typiques de l'environnement. Elle montre qu'un appareillage simple, utilisé sans grande précaution et sans trop se soucier de la reproductibilité des conditions d'échantillonnage parvient à identifier correctement l'origine des odeurs qu'on lui propose. [less ▲]

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See detailFirst trends towards a field odour detector for environmental applications
Nicolas, Jacques ULiege; Romain, Anne-Claude ULiege; Wiertz, V. et al

in Weimar, Udo (Ed.) Proceedings of ISOEN 99 (1999)

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See detailIdentification of pollutant gases with a multisensorial arrange.
Negri, Martin; Reich, S.; Fernandez, D. et al

in Weimar, Udo (Ed.) proceedings of ISOEN 99 (1999)

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See detailDéveloppement de techniques d'identification d'odeurs dans l'environnement
Nicolas, Jacques ULiege; Romain, Anne-Claude ULiege; Wiertz, Véronique et al

Report (1998)

Different techniques of evaluation of environmental odours were analysed and tested. More particularly, gas chromatography/mass spectrometry and electronic nose were investigated on 5 environmental ... [more ▼]

Different techniques of evaluation of environmental odours were analysed and tested. More particularly, gas chromatography/mass spectrometry and electronic nose were investigated on 5 environmental sources : printing house, compost area, waste water treatment plant, coach building and slaughter house. It is shown that electronic nose is a promising instrument able to identify qualitatively the odour type and to provide a global indicator of the odour level. [less ▲]

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See detailNez électronique adapté aux odeurs de sucrerie, Rapport final
Romain, Anne-Claude ULiege; Nicolas, Jacques ULiege

Report (1998)

Au terme de cette convention FIRST, un savoir faire en matière de mesure d'odeur environnementale a été développé à sur le campus d'Arlon. Ce savoir faire étoffe ainsi l'acquis de l'équipe de recherche ... [more ▼]

Au terme de cette convention FIRST, un savoir faire en matière de mesure d'odeur environnementale a été développé à sur le campus d'Arlon. Ce savoir faire étoffe ainsi l'acquis de l'équipe de recherche "Surveillance de l'Environnement". Un détecteur de nuisances olfactives a été développé en laboratoire. Ce système s'avère au moins aussi performant que les instruments proposés sur le marché. Dans notre cas, la technologie des nez artificiels a été adaptée au monitoring des odeurs dans l'environnement : notamment les influences des facteurs externes, comme la température et l'humidité ambiantes ont été étudiées. Les quelques odeurs environnementales (prélevées sur le terrain ou reconstituées artificiellement) testées sur le détecteur ont pu être identifiées par des techniques de reconnaissance de formes. Couplé à l'acquisiteur de données VIGIL de C2MS, un détecteur de terrain a été placé sur le terrain, aux alentours des bassins de décantation de la sucrerie "Tirlemont" de Genappe. Moyennant une calibration des algorithmes utilisés, il va donc servir à la surveillance continue des émissions olfactives sur le site considéré, notamment dans le but de mettre en évidence un indicateur d'alarme ou de délivrer un signal capable de contrôler un aérateur de bassin. A l'issue des 3 années de recherche, on peut donc considérer que l'instrument de laboratoire et le détecteur de terrain fonctionnent de manière satisfaisante et, en tout état de cause, suffisamment bien que pour être transposés à d'autres applications environnementales, au-delà de celle du monitoring des odeurs de sucrerie. Il est notamment projeté d'adapter une technique similaire à celle du détecteur de terrain au suivi des émissions olfactives aux alentours de décharges d'ordures, l'objectif étant le contrôle des dispositifs anti-odeurs. Chaque émission d'odeur est un cas spécifique : il sera donc difficilement envisageable, dans l'avenir, de commercialiser un appareil universel. Une perspective intéressante serait d'adapter le détecteur de terrain, au cas par cas, à d'autres suivis d'odeurs environnementales, en se servant des acquis de cette première expérience et de l'instrument de laboratoire comme banc d'essais préliminaires. [less ▲]

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See detailParticipation à la surveillance de l'environnement de la sidérurgie Arbed-Luxembourg
Romain, Anne-Claude ULiege

Master of advanced studies dissertation (1993)

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See detailSTUDY OF THE CRYSTALLIZATION PROCESS IN BI2-XPBXSR2CA2CU3O10-Y GLASS SYSTEMS - OPTICAL POLARIZED-LIGHT MICROSCOPY, ELECTRICAL AND MAGNETIC-PROPERTIES
Cloots, Rudi ULiege; Romain, Anne-Claude ULiege; Rulmont, André ULiege et al

in Superconductor Science and Technology (1993), 6(12), 850-857

Synthesis of Bi2-xPbxSr2Ca2Cu3O10-y (x = 0 and x = 0.3) has been performed using the glass recrystallization route technique. After splat quenching, the samples were annealed at 820, 850 or 870-degrees-C ... [more ▼]

Synthesis of Bi2-xPbxSr2Ca2Cu3O10-y (x = 0 and x = 0.3) has been performed using the glass recrystallization route technique. After splat quenching, the samples were annealed at 820, 850 or 870-degrees-C for 96 or 144 h (with one intermediary grinding). High-resolution polarization micrographs and electrical (and magnetic susceptibility) measurements have been taken. Various growth mechanisms can thus be checked, and the physical properties are studied in relation to the microstructure. It is found that the 2223 phase does not crystallize directly from the amorphous one but results from a dissolution-reprecipitation process. The stability of the 2212 phase is emphasized. The 2201 phase precipitates at high temperature and rapidly reacts with the melt to form the 2223 phase. The kinetics of the lead-substituted sample seems to be controlled by the Ca2PbO4 phase. which acts as a flux. [less ▲]

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