Fabrice De Oliveira | CSTB (original) (raw)
Papers by Fabrice De Oliveira
International audienceClassical physicochemical or sensory methodologies are often inadequate to ... more International audienceClassical physicochemical or sensory methodologies are often inadequate to describe the perception of water and their correlation is complicated. Indeed, the taste of water is difficult to describe due to low concentrations of sapid molecules. The aim of this work was to combine sensory and physiological measurements in order to correlate data with chemical properties of sapid solutions
Monitoring systems are prone to record huge amount of data, only a minor part of which could be o... more Monitoring systems are prone to record huge amount of data, only a minor part of which could be of interest. Maintaining a giant data base from the monitoring system of a large structure equipped with dozens of sensors is a costly challenge. One way for solving this question lies in discarding everything that does not enter in the scope of what was considered as "interesting event " at the design stage, with a big risk of missing an unattended but essential event. Another way could be to store less data, making a kind of "survey " instead of recording continuously, with a possibility to rebuild events from the discontinuous records. This way of doing is suitable in the case of minutes lasting phenomena only, it is clear that a sudden and brief phenomenon could be missed in such a configuration. This method was used in the case of vortex shedding excitation of the deck of a large cable stayed bridge, in order to rebuild the history of passed excitations and evalua...
Cette etude consiste a elaborer une methode d'evaluation du confort thermique objectivement r... more Cette etude consiste a elaborer une methode d'evaluation du confort thermique objectivement ressenti par l'homme. Cette methode s'appuie en particulier sur des indicateurs peripheriques de l'activite du systeme nerveux autonome (SNA) lie a la thermoregulation, afin d'integrer la composante objective du confort thermique ressenti. Notre approche est basee sur une evaluation multiparametrique et ojective du confort thermique ressenti. Nous avons identifie des indicateurs physiologiques qui permettent de restituer les reactions de la thermoregulation a partir de l’activation du SNA, c'est-a-dire des variables temporelles qui permettent de visualiser des episodes de reactions non conscientes ou faiblement conscientes lies a un stimulus. Nous avons identifie un ensemble d’indices susceptibles de constituer un set complet de parametres thermoneuro- vasculaires afin d’aprehender les reactions physiologiques non conscientes de l’homme. Ces indicateurs physiologiques ...
Le gout de l’eau est difficile a expliciter, du fait du milieu lui-meme, suppose sans gout. Les m... more Le gout de l’eau est difficile a expliciter, du fait du milieu lui-meme, suppose sans gout. Les methodes classiques d’analyse sensorielle sont insuffisantes pour decrire la perception. L’utilisation de mesures physiologiques specifiques permet de qualifier et quantifier le gout de l’eau. Les quatre gouts de base (sucre, sale, acide, amer) ont ete utilises, dilues dans l’eau d’Evian comme reference, a de faibles concentrations. Les resultats des variations de microcirculation cutanee indiquent une forte correlation entre la duree et l’amplitude de la reponse et l’intensite d’une part, et entre la duree et l’amplitude de la reponse et l’appreciation globale du stimulus d’autre part. Les mesures physiologiques semblent permettre la discrimination significative des differentes saveurs, meme a des concentrations aux seuils de detection.
Applied Thermal Engineering, 2017
h i g h l i g h t s This paper focuses on the temperature field of the transmission part in a lun... more h i g h l i g h t s This paper focuses on the temperature field of the transmission part in a lunar drilling system. FEM and TNM models are used to predict the temperature field of the transmission part. A vacuum test platform is established to measure the temperature rise in different working modes. The effects of the rotating speed, system load and ambient temperature on the temperature rise are analysed. Research on the temperature field and heat transfer path can help control the working strategy
2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006
Pressure ulcers constitute an important health problem. They affect lots of people with mobility ... more Pressure ulcers constitute an important health problem. They affect lots of people with mobility disorder and they are difficult to detect and prevent because the damage begins on the muscle. This paper proposes a new approach to study pressure ulcers. We aim at developing a methodology to analyse the probability for a patient to develop a pressure ulcer, and that can detect risky situation. The idea is to relate the mobility disorder to autonomic nervous system (ANS) trouble. More precisely, the evaluation of the consequence of the discomfort on the ANS (stress induced by discomfort) can be relevant for the early detection of the pressure ulcer. Mobility is evaluated through movement measurement. This evaluation, at the interface between soft living tissues and any support has to consider the specificity of the human environment. Soft living tissues have non-linear mechanical properties making conventional rigid sensors non suitable for interface parameters measurement. A new actimeter system has been designed in order to study movements of the human body whatever its support while seating. The device is based on elementary active cells. The number of pressure cells can be easily adapted to the application. The spatial resolution is about 4 cm(2). In this paper, we compare activity measurement of a seated subject with his autonomic nervous system activity, recorded by E.motion device. It has been developed in order to record six parameters: skin potential, skin resistance, skin temperature, skin blood rate, instantaneous cardiac frequency and instantaneous respiratory frequency. The design, instrumentation, and first results are presented.
Critical Reviews in Environmental Science and Technology, 2014
ABSTRACT Usually, organoleptic criteria have to be fulfilled for tap water in order for it to be ... more ABSTRACT Usually, organoleptic criteria have to be fulfilled for tap water in order for it to be considered safe to drink. This can be achieved at three levels: chemical analysis, sensory analysis, or through electrophysiology. While chemical analysis has been quite extensively discussed in the literature and as consumer perception is of vital importance, we propose a review of the latter two levels, namely sensory analysis and electrophysiology. We first recall some basics of perception and how it can be influenced by stimuli properties, human intrinsic factors and contextual factors, which are critical for an efficient measurement. Next, we present sensory analysis methods, as these are usually carried out in order to measure consumer appreciation of water. The drawbacks of such methods are then discussed before introducing the alternative of electrophysiological measurements. Some evidence that activity from the central and autonomic nervous systems can be measured in response to gustatory and olfactory stimuli in water is first described. Then, a review of objective physiological methods in the literature, developed to assess the emotional aspect of these reactions, is detailed. Finally, the possibility of correlating and predicting the quality, intensity, and hedonic dimension of a stimulus in water with sensory self-report and nervous system responses is discussed.
Actes du 10ème …, 2010
Le contexte actuel de la ville durable vise, entre autres, à améliorer la qualité de vie des cita... more Le contexte actuel de la ville durable vise, entre autres, à améliorer la qualité de vie des citadins. Le travail présenté ici propose une approche multicritères afin d'évaluer le confort en milieu urbain. Plusieurs thématiques sont prises en compte dans cette méthodologie pluridisciplinaire : l'acoustique, l'éclairage, l'aérothermie, la qualité de l'air, les odeurs, l'esthétique, la dimension sociale et l'aménagement urbain. Il s'agit, à partir à la fois d'expérimentations et de simulations, de confronter plusieurs paramètres afin d'avoir une évaluation globale du confort du citadin dans un lieu de vie extérieur. Les expérimentations sont d'une part physiques (mesures de niveaux de bruit, d'éclairement, …) et d'autre part psychosociales (enquêtes in-situ, enquête sur les représentations sociales, …). Ces différents paramètres sont confrontés et comparés sur deux espaces publics pour évaluer les déterminants du confort du citadin. Le protocole d'évaluation porte en effet sur deux espaces urbains (deux places publiques en Ile-de-France). Cette étude fait ressortir des critères de confort, susceptibles d'être appliqués à d'autres espaces publics urbains.
Wind and Structures, Dec 1, 2017
A novel probabilistic approach is presented for estimating the equivalent static wind loads that ... more A novel probabilistic approach is presented for estimating the equivalent static wind loads that produce a static response of the structure, which is "equivalent" in a probabilistic sense, to the extreme dynamic responses due to the unsteady pressure random field induced by the wind. This approach has especially been developed for complex structures (such as stadium roofs) for which the unsteady pressure field is measured in a boundary layer wind tunnel with a turbulent incident flow. The proposed method deals with the non-Gaussian nature of the unsteady pressure random field and presents a model that yields a good representation of both the quasi-static part and the dynamical part of the structural responses. The proposed approach is experimentally validated with a relatively simple application and is then applied to a stadium roof structure for which experimental measurements of unsteady pressures have been performed in boundary layer wind tunnel.
A novel probabilistic approach is presented for estimating the equivalent static wind loads that ... more A novel probabilistic approach is presented for estimating the equivalent static wind loads that produce a static response of the structure, which is "equivalent" in a probabilistic sense, to the dynamic responses due to the pressure random field induced by the wind. This approach has especially been developed for the case for which a large number of unsteady pressure measurements are carried out on complex structures (such stadium roofs) in a wind tunnel, the random pressure field is non-Gaussian, and the quasi-static part of the responses is important with respect to the dynamical part. The proposed approach is demonstrated with a simple illustrative example.
Indoor and Built Environment
A neuro-human thermal model was optimized to increase the prediction accuracy of the physiologica... more A neuro-human thermal model was optimized to increase the prediction accuracy of the physiological variables of a group of 15 healthy male students exposed to transient environmental conditions. The effect of both the passive and active systems parameters was studied using a sensitivity analysis, and the parameters that had the most influence on the neuro-human thermal model outputs were established. A genetic algorithm was then used to optimize the model in order to determine the parameters that corresponded to the studied population. The results showed that the optimization increased the precision of the neuro-human thermal model. The mean absolute error and the maximum error between the experimental data and the numerical results for mean skin temperature were 0.13°C and 0.56°C, respectively, and we obtained 0.03°C and 0.11°C, respectively, for rectal temperature. These results show that the neuro-human thermal model can be accurately adjusted for the rectal, mean and local skin ...
International Journal of Biometeorology
Journal of Wind Engineering and Industrial Aerodynamics
ABSTRACT Monitoring systems are nowadays usually provided on large bridges, the decision being ta... more ABSTRACT Monitoring systems are nowadays usually provided on large bridges, the decision being taken as early as the initial design process. After completion they are very valuable for providing data about the actual behavior of the structure under real wind, which can usefully be compared with design models. The Charilaos Trikoupis Bridge, between Rion and Antirion in Greece, was equipped with a very complete monitoring system including accelerometers on the deck, pylons and cables along the four spans as well as anemometers. This system is perfectly maintained by permanent staff of the bridge owner, and gives information about the bridge׳s structural health which is regularly used for maintenance purposes. This smart system continuously records only sparse data, with a complete dynamic check being performed every 2 h. This monitoring system was also designed to trigger detailed recording following specific events. From recorded data, cable vibration has been observed after bridge completion and the bridge owner suppressed this within several months by installing dampers between the deck and the cables. Limited-amplitude vertical vibration of the deck in the third mode was also observed on some occasions. The bridge owner asked a foreign laboratory to process two years of monitoring data in order to fully understand the origin of this vibration and evaluate whether treatment would be necessary.
International audienceClassical physicochemical or sensory methodologies are often inadequate to ... more International audienceClassical physicochemical or sensory methodologies are often inadequate to describe the perception of water and their correlation is complicated. Indeed, the taste of water is difficult to describe due to low concentrations of sapid molecules. The aim of this work was to combine sensory and physiological measurements in order to correlate data with chemical properties of sapid solutions
Monitoring systems are prone to record huge amount of data, only a minor part of which could be o... more Monitoring systems are prone to record huge amount of data, only a minor part of which could be of interest. Maintaining a giant data base from the monitoring system of a large structure equipped with dozens of sensors is a costly challenge. One way for solving this question lies in discarding everything that does not enter in the scope of what was considered as "interesting event " at the design stage, with a big risk of missing an unattended but essential event. Another way could be to store less data, making a kind of "survey " instead of recording continuously, with a possibility to rebuild events from the discontinuous records. This way of doing is suitable in the case of minutes lasting phenomena only, it is clear that a sudden and brief phenomenon could be missed in such a configuration. This method was used in the case of vortex shedding excitation of the deck of a large cable stayed bridge, in order to rebuild the history of passed excitations and evalua...
Cette etude consiste a elaborer une methode d'evaluation du confort thermique objectivement r... more Cette etude consiste a elaborer une methode d'evaluation du confort thermique objectivement ressenti par l'homme. Cette methode s'appuie en particulier sur des indicateurs peripheriques de l'activite du systeme nerveux autonome (SNA) lie a la thermoregulation, afin d'integrer la composante objective du confort thermique ressenti. Notre approche est basee sur une evaluation multiparametrique et ojective du confort thermique ressenti. Nous avons identifie des indicateurs physiologiques qui permettent de restituer les reactions de la thermoregulation a partir de l’activation du SNA, c'est-a-dire des variables temporelles qui permettent de visualiser des episodes de reactions non conscientes ou faiblement conscientes lies a un stimulus. Nous avons identifie un ensemble d’indices susceptibles de constituer un set complet de parametres thermoneuro- vasculaires afin d’aprehender les reactions physiologiques non conscientes de l’homme. Ces indicateurs physiologiques ...
Le gout de l’eau est difficile a expliciter, du fait du milieu lui-meme, suppose sans gout. Les m... more Le gout de l’eau est difficile a expliciter, du fait du milieu lui-meme, suppose sans gout. Les methodes classiques d’analyse sensorielle sont insuffisantes pour decrire la perception. L’utilisation de mesures physiologiques specifiques permet de qualifier et quantifier le gout de l’eau. Les quatre gouts de base (sucre, sale, acide, amer) ont ete utilises, dilues dans l’eau d’Evian comme reference, a de faibles concentrations. Les resultats des variations de microcirculation cutanee indiquent une forte correlation entre la duree et l’amplitude de la reponse et l’intensite d’une part, et entre la duree et l’amplitude de la reponse et l’appreciation globale du stimulus d’autre part. Les mesures physiologiques semblent permettre la discrimination significative des differentes saveurs, meme a des concentrations aux seuils de detection.
Applied Thermal Engineering, 2017
h i g h l i g h t s This paper focuses on the temperature field of the transmission part in a lun... more h i g h l i g h t s This paper focuses on the temperature field of the transmission part in a lunar drilling system. FEM and TNM models are used to predict the temperature field of the transmission part. A vacuum test platform is established to measure the temperature rise in different working modes. The effects of the rotating speed, system load and ambient temperature on the temperature rise are analysed. Research on the temperature field and heat transfer path can help control the working strategy
2006 International Conference of the IEEE Engineering in Medicine and Biology Society, 2006
Pressure ulcers constitute an important health problem. They affect lots of people with mobility ... more Pressure ulcers constitute an important health problem. They affect lots of people with mobility disorder and they are difficult to detect and prevent because the damage begins on the muscle. This paper proposes a new approach to study pressure ulcers. We aim at developing a methodology to analyse the probability for a patient to develop a pressure ulcer, and that can detect risky situation. The idea is to relate the mobility disorder to autonomic nervous system (ANS) trouble. More precisely, the evaluation of the consequence of the discomfort on the ANS (stress induced by discomfort) can be relevant for the early detection of the pressure ulcer. Mobility is evaluated through movement measurement. This evaluation, at the interface between soft living tissues and any support has to consider the specificity of the human environment. Soft living tissues have non-linear mechanical properties making conventional rigid sensors non suitable for interface parameters measurement. A new actimeter system has been designed in order to study movements of the human body whatever its support while seating. The device is based on elementary active cells. The number of pressure cells can be easily adapted to the application. The spatial resolution is about 4 cm(2). In this paper, we compare activity measurement of a seated subject with his autonomic nervous system activity, recorded by E.motion device. It has been developed in order to record six parameters: skin potential, skin resistance, skin temperature, skin blood rate, instantaneous cardiac frequency and instantaneous respiratory frequency. The design, instrumentation, and first results are presented.
Critical Reviews in Environmental Science and Technology, 2014
ABSTRACT Usually, organoleptic criteria have to be fulfilled for tap water in order for it to be ... more ABSTRACT Usually, organoleptic criteria have to be fulfilled for tap water in order for it to be considered safe to drink. This can be achieved at three levels: chemical analysis, sensory analysis, or through electrophysiology. While chemical analysis has been quite extensively discussed in the literature and as consumer perception is of vital importance, we propose a review of the latter two levels, namely sensory analysis and electrophysiology. We first recall some basics of perception and how it can be influenced by stimuli properties, human intrinsic factors and contextual factors, which are critical for an efficient measurement. Next, we present sensory analysis methods, as these are usually carried out in order to measure consumer appreciation of water. The drawbacks of such methods are then discussed before introducing the alternative of electrophysiological measurements. Some evidence that activity from the central and autonomic nervous systems can be measured in response to gustatory and olfactory stimuli in water is first described. Then, a review of objective physiological methods in the literature, developed to assess the emotional aspect of these reactions, is detailed. Finally, the possibility of correlating and predicting the quality, intensity, and hedonic dimension of a stimulus in water with sensory self-report and nervous system responses is discussed.
Actes du 10ème …, 2010
Le contexte actuel de la ville durable vise, entre autres, à améliorer la qualité de vie des cita... more Le contexte actuel de la ville durable vise, entre autres, à améliorer la qualité de vie des citadins. Le travail présenté ici propose une approche multicritères afin d'évaluer le confort en milieu urbain. Plusieurs thématiques sont prises en compte dans cette méthodologie pluridisciplinaire : l'acoustique, l'éclairage, l'aérothermie, la qualité de l'air, les odeurs, l'esthétique, la dimension sociale et l'aménagement urbain. Il s'agit, à partir à la fois d'expérimentations et de simulations, de confronter plusieurs paramètres afin d'avoir une évaluation globale du confort du citadin dans un lieu de vie extérieur. Les expérimentations sont d'une part physiques (mesures de niveaux de bruit, d'éclairement, …) et d'autre part psychosociales (enquêtes in-situ, enquête sur les représentations sociales, …). Ces différents paramètres sont confrontés et comparés sur deux espaces publics pour évaluer les déterminants du confort du citadin. Le protocole d'évaluation porte en effet sur deux espaces urbains (deux places publiques en Ile-de-France). Cette étude fait ressortir des critères de confort, susceptibles d'être appliqués à d'autres espaces publics urbains.
Wind and Structures, Dec 1, 2017
A novel probabilistic approach is presented for estimating the equivalent static wind loads that ... more A novel probabilistic approach is presented for estimating the equivalent static wind loads that produce a static response of the structure, which is "equivalent" in a probabilistic sense, to the extreme dynamic responses due to the unsteady pressure random field induced by the wind. This approach has especially been developed for complex structures (such as stadium roofs) for which the unsteady pressure field is measured in a boundary layer wind tunnel with a turbulent incident flow. The proposed method deals with the non-Gaussian nature of the unsteady pressure random field and presents a model that yields a good representation of both the quasi-static part and the dynamical part of the structural responses. The proposed approach is experimentally validated with a relatively simple application and is then applied to a stadium roof structure for which experimental measurements of unsteady pressures have been performed in boundary layer wind tunnel.
A novel probabilistic approach is presented for estimating the equivalent static wind loads that ... more A novel probabilistic approach is presented for estimating the equivalent static wind loads that produce a static response of the structure, which is "equivalent" in a probabilistic sense, to the dynamic responses due to the pressure random field induced by the wind. This approach has especially been developed for the case for which a large number of unsteady pressure measurements are carried out on complex structures (such stadium roofs) in a wind tunnel, the random pressure field is non-Gaussian, and the quasi-static part of the responses is important with respect to the dynamical part. The proposed approach is demonstrated with a simple illustrative example.
Indoor and Built Environment
A neuro-human thermal model was optimized to increase the prediction accuracy of the physiologica... more A neuro-human thermal model was optimized to increase the prediction accuracy of the physiological variables of a group of 15 healthy male students exposed to transient environmental conditions. The effect of both the passive and active systems parameters was studied using a sensitivity analysis, and the parameters that had the most influence on the neuro-human thermal model outputs were established. A genetic algorithm was then used to optimize the model in order to determine the parameters that corresponded to the studied population. The results showed that the optimization increased the precision of the neuro-human thermal model. The mean absolute error and the maximum error between the experimental data and the numerical results for mean skin temperature were 0.13°C and 0.56°C, respectively, and we obtained 0.03°C and 0.11°C, respectively, for rectal temperature. These results show that the neuro-human thermal model can be accurately adjusted for the rectal, mean and local skin ...
International Journal of Biometeorology
Journal of Wind Engineering and Industrial Aerodynamics
ABSTRACT Monitoring systems are nowadays usually provided on large bridges, the decision being ta... more ABSTRACT Monitoring systems are nowadays usually provided on large bridges, the decision being taken as early as the initial design process. After completion they are very valuable for providing data about the actual behavior of the structure under real wind, which can usefully be compared with design models. The Charilaos Trikoupis Bridge, between Rion and Antirion in Greece, was equipped with a very complete monitoring system including accelerometers on the deck, pylons and cables along the four spans as well as anemometers. This system is perfectly maintained by permanent staff of the bridge owner, and gives information about the bridge׳s structural health which is regularly used for maintenance purposes. This smart system continuously records only sparse data, with a complete dynamic check being performed every 2 h. This monitoring system was also designed to trigger detailed recording following specific events. From recorded data, cable vibration has been observed after bridge completion and the bridge owner suppressed this within several months by installing dampers between the deck and the cables. Limited-amplitude vertical vibration of the deck in the third mode was also observed on some occasions. The bridge owner asked a foreign laboratory to process two years of monitoring data in order to fully understand the origin of this vibration and evaluate whether treatment would be necessary.