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7. Krill diel vertical migration fine dynamics, nocturnal overturns, and their roles for aggregation in stratified flows

Author

Sourisseau, M., Simard, Y., and Saucier, F.J.

Subjects
Animal migration -- Observations, Krill -- Behavior, Earth sciences
Abstract

Abstract: A set of high-resolution observations on short-term dynamics of krill diel vertical migrations (DVM) in the St. Lawrence Estuary are presented here, including vertical mass transfer measurements from multifrequency [...]

Published
2008

8. Extensional flow mixer for polymer nanocomposites

Author

Tokihisa, M., Yakemoto, K., Sakai, T., Utracki, L.A., Sepehr, M., Li, J., and Simard, Y.

Subjects
Nanotechnology -- Research, Polymeric composites -- Production processes -- Research, Engineering and manufacturing industries, Science and technology, Production processes, Research
Abstract

The extensional flow mixer (EFM) has been used in industry, for e.g., homogenization of reactor products, polymer blending, incorporation of plasticizer, etc. Recently, several laboratories attempted to use EFM for dispersing organoclay in a molten polymer. Thus, usually EFM was mounted on a twin-screw extruder equipped with a gear pump. The use of EFM resulted in improved dispersion and performance--more significant in polyamide or thermoplastic polyester--and marginal in a polyolefin or polystyrene. Recently, to improve EFM efficiency, the commercial EFM-3 was modified by redesigning the convergent-divergent plates that engender the extensional flow. The two mixers, EFM-3 and the new EFM-N, were evaluated using a single-screw extruder. Two systems were examined: (1) polyamide-6 (PA-6) with Cloisite®-15A (C15A) and (2) polypropylene with maleated-PP and C15A. The compounded samples were injection-molded, and then tested for the degree of dispersion and mechanical performance. The results showed superiority of EFM-N. Compounding PA-6 with C15A in a single-screw extruder with EFM-N exfoliated the organoclay, producing polymeric nanocomposites with high performance, comparable or better than that of a commercial nanocomposite produced by polycondensation of ζ-caprolactam in the presence of clay, pre-intercalated with reactive cations. POLYM. ENG. SCI., 46: 1040-1050, 2006. © 2006 Society of Plastics Engineers, INTRODUCTION Currently, the production of polymeric nanocomposites (PNCs) is based mainly on the reactive method, i.e., polymerization of given monomer(s) in the presence of preintercalated mineral or synthetic clay [1-3]. [...]

Published
2006

9. Effect of shrinkage and process parameters on the monitoring of bulk and surface stream temperatures in injection molding via the infrared waveguide method

Author

Bendada, A., Simard, Y., and Lamontagne, M.

Subjects
Polymers -- Research, Engineering and manufacturing industries, Science and technology
Abstract

This paper analyzes for the first time the application of the infrared hollow waveguide method for the remote sensing of the temperature decay of polymer streams during injection molding. The key feature of the infrared procedure employed is its low transmission loss of the thermal energy in the mid and far infrared spectral regions. This particular advantage allows the hollow waveguide device to measure not only the bulk temperature within the polymer, as commercially available full-core optical fiber instruments do, but also the temperature at the polymer surface. Moreover, the hollow waveguide device is able to measure quite low temperatures, which conventional thermometers cannot do either. Experimental trials have been run on a Husky injection molding press in order to investigate the effect of some process parameters and shrinkage on the bulk and surface temperature decay signals. The results showed a drastic deviation between the kinetic behaviors of the surface and bulk temperature traces throughout the injection cycle. Particularly, it was noticed that the cooling rate of the surface temperature was more affected by part shrinkage than the cooling rate of the bulk temperature. The experimental results showed also that temperatures below 60[degrees]C could be reliably measured with reasonable signal-over-noise ratio. Polym. Eng. Sci. 44:955-964, 2004., INTRODUCTION In polymer injection molding, the material undergoes a complex history in which it is melted, flows through complex geometries where viscous dissipation, shrinkage and warpage play a central role, [...]

Published
2004

16. Blue whale songs worldwide: an update

Author

Sirovic, Ana, McDonald, M, Balcazar-Cabrera, NE, Buchan, Susannah, Cerchio, S, Clark, C. W., Davis, G, Findlay, Ken, Gagnon, G, Kyo, N, Leroy, Emmanuelle, Miksis-Olds, Jennifer, Miller, Brian, Oleson, EM, Pangerc, T, Rogers, T., Samaran, Flore, Simard, Y, Stafford, Kate, Stevenson, D, Sugioka, H, Thomisch, Karolin, Tripovich, J, Truong, G, van Opzeeland, Ilse, Van Parijs, S. M., Yoshida, R, Brownell Jr, RL, Sirovic, Ana, McDonald, M, Balcazar-Cabrera, NE, Buchan, Susannah, Cerchio, S, Clark, C. W., Davis, G, Findlay, Ken, Gagnon, G, Kyo, N, Leroy, Emmanuelle, Miksis-Olds, Jennifer, Miller, Brian, Oleson, EM, Pangerc, T, Rogers, T., Samaran, Flore, Simard, Y, Stafford, Kate, Stevenson, D, Sugioka, H, Thomisch, Karolin, Tripovich, J, Truong, G, van Opzeeland, Ilse, Van Parijs, S. M., Yoshida, R, and Brownell Jr, RL

Abstract

Blue whales produce regionally-distinct songs. In over a decade since McDonald and colleagues published a summary of biogeographic differences in blue whale songs worldwide, multiple new publications have explored the seasonality and distribution of those songs. We review the spatial and temporal occurrence of previously-defined song types and report several new blue whale song types. At least thirteen songs believed to be produced by blue whales are now known worldwide, five more than reported in the previous review. In the North Pacific Ocean there are three blue whale songs: the well-studied Northeast Pacific song, the Central North Pacific (previously called Northwest and North Pacific) song, and a new song recorded off Hokkaido, Japan. There is spatial overlap of the Northeast Pacific and Central North Pacific songs in the Gulf of Alaska. Similarly, the new song co-occurs with the Central North Pacific song off Hokkaido. Only one blue whale song occurs in the North Atlantic. At least nine songs are present in the Southern Hemisphere. The Antarctic blue whale song is the most widely distributed, occurring in the Southern Ocean as well as seasonally extending into the other oceans of the Southern Hemisphere. The Indian Ocean has the largest variety of blue whale songs, with new data suggesting the Southwest Indian Ocean song should have type locality Madagascar, with Diego Garcia possibly another song-type. Southeast Pacific contains two distinct, co-occurring songs. We report a new song in the South Atlantic, near South Georgia Island, that also occurs seasonally off Ascension Island. Occasionally blue whale songs were recorded outside of their reported range, indicating individuals at times roam more broadly. However, this is not a common occurrence. This new information and finer details of occurrence will enable further development of hypotheses for blue whale population structure based on acoustics.

Published
2017

17. Time-delay estimation based on Cross Recurrence Plot and Joint Recurrence Plot for passive underwater acoustic source localization

Author

Le Bot, Olivier, Gervaise, Cedric, Mars, Jerome, Simard, Y, GIPSA - Signal Images Physique (GIPSA-SIGMAPHY), Département Images et Signal (GIPSA-DIS), Grenoble Images Parole Signal Automatique (GIPSA-lab), Université Stendhal - Grenoble 3-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Stendhal - Grenoble 3-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Grenoble Images Parole Signal Automatique (GIPSA-lab), Université Stendhal - Grenoble 3-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Stendhal - Grenoble 3-Université Pierre Mendès France - Grenoble 2 (UPMF)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Chaire CHORUS - Fondation Grenoble-INP, Institut Polytechnique de Grenoble - Grenoble Institute of Technology, Université du Québec à Rimouski (UQAR), Maurice-Lamontagne Institute, Fisheries and Oceans Canada (DFO), and Mars, Jerome

Subjects
[SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, [SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience; Passive acoustic localization of underwater sources, like cetaceans, is generally based on a two steps approach. First step consists in a time-delay estimation (TDE), which aims at measuring the relative time difference of arrival (TDOA) of the signal on spatially separated sensors. Second step consists in determining the position of the source from a set of estimated TDOA related to the array geometry, by using a spatial inversion algorithm. In this presentation we only focus on the first step. The most popular method for time-delay estimation in underwater acoustic is the cross-correlation. However, this method has some weaknesses when the signal of interest is mixed in high-level background noise and propagate in reverberant and dispersive environment that warp the waveform of the signals received at different sensors. In such conditions, the cross-correlation gives poor and unreliable estimates of the time-delay, particularly if a low percentage of samples look alike on the different sensors.In this presentation, we propose to use Cross Recurrence Plot (CRP) and Joint Recurrence Plot (JRP) to estimate the time-delay. First, we identify samples that are recurrent on the different sensors, by calculating the CRP and the JRP between pairs of sensors. Then, we use recurrence quantification analysis (RQA) to estimate the time-delay. Several RQA metrics such as the longest diagonal line Lmax , the longest curved trace, the diagonal-wise tau-recurrence rate, the recurrence rate and the joint probability of recurrence are considered for this purpose. The most reliable RQA metric for TDE is determined through performance analysis tests involving simulated signals with known time-delay. The influence of the embedding dimension m, of the delay tau and of the recurrence threshold on the performances of the TDE are also discussed. Finally, the proposed method is validated on real data recorded at sea by an hydrophone array and containing cetacean and fish vocalizations.

Published
2015

19. ACIDOSIS WITH 'NORMAL' ANION GAP DURING PROPOFOL INFUSION

Author

Senecal, PE, Chalut, D, Simard, Y, and Lefebvre, M

Subjects
Propofol -- Adverse and side effects, Antidotes -- Adverse and side effects, Acidosis -- Causes of, Environmental issues, Health, Pharmaceuticals and cosmetics industries
Abstract

Background: Propofol (2,6-diisopropylphenol), an iv anesthetic formulated as a white oil, is used in children, despite its innocuity for sedation not being well established. In pediatrics, propofol-associated acidosis has been reported. Case Report: Day 1, a 6.1 kg 5-month-old male received propofol during and after cleft lip surgery. Day 3, when the infusion rate was up to 15 mg/kg/h, acidosis (pH 7.21, p[CO.sub.2] 46, BIC 19,; Na 132, CI 108), green urine and gross lipemia were noted. Vitals: BP 75/35, HR 127 with normal temperature. Osmolality, creatinine, glucose, L-lactate: normal. Propofol was stopped (after a total of 720 mg/kg in 62.5 hours). Senm propofol then was 171 mg/L (adult therapeutic range: 1.5-6 mg/L). Day 4, one hour after an ionized calcium of 1.0 mmol/L: bradycardia (90/min) and ventricular tachycardia developed requiring CPR. Seven hours after: ABG pH 7.23, p[CO.sub.2] 36, BIC 15; Na 137, C1 113, L-lactate 6.5 mmol/ L, and ketones negative. N-acetylcysteine (50 mg/kg), and L-carnitine 50 mg/kg were given to limit the peaks of AST (6459), CK (7695), INR (12.3), creatinine (1.7 mg%) and lactate (9.6). Hemodialysis (HD) and hemoperfusion had little effect on senm propofol: 1.2 mg/L (day 4 before CPR and HD) and 1.3 mg/L (day 8) although HD corrected the base deficit transiently. ICU stay was 23 days. Propofol was measured, after chloroform extraction at pH 11.7, by splitless injection in an HP 5973 GC with MS single ion monitoring at m/z of 163 and 178 (or 107 and 122 for the 2,4-dimethylphenol internal standard). Conclusion: We report a near-fatal pediatric adverse event preceded by an elevated propofol concentration and a metabolic acidosis, with some features suggestive of renal tubular acidosis. In pediatrics, caution is advised if propofol is to be used for sedation at rates [is greater than] 10 mg/kg or for more than 8 hours duration., Senecal PE, Chalut D, Simard Y, Lefebvre M. McGill University Health Centre, Montreal, PQ, Canada; Centre de Toxicologie du Quebec, Ste-Foy, PQ, [...]

Published
2000

20. Krill diel vertical migration fine dynamics, nocturnal overturns, and their roles for aggregation in stratified flows (vol 65, pg 574, 2008)

Author

Sourisseau, Marc, Simard, Y., and Saucier, F. J.

Abstract

A set of high-resolution observations on short-term dynamics of krill diel vertical migrations (DVM) in the St. Lawrence Estuary are presented here, including vertical mass transfer measurements from multifrequency echo sounding coupled with stratified net sampling and tracers of individual vertical movements from stomach pigments over a 72 h period. The data set is supplemented by vertical migration speeds and biomass diel patterns from ADCP (acoustic Doppler current profiler) time series lasting up to 3 months. All krill always rapidly migrated to the surface in synchrony at sunset. Soon after the ascent, fed krill started to swim downward. A scattering layer was then formed at their daytime depth with sometimes a significant backscatter at intermediate depths, especially around midnight. A reorganisation in the upper water column then occurs, likely for a predawn feeding bout. At dawn, the krill mass still feeding in upper water column synchronously swam downward to their daytime depth. This nocturnal asynchronous vertical behaviour, conforming to the DVM hunger-satiation hypothesis, repeated between August and October in two different years, the DVM timing being determined by day length., Un ensemble d'observations à haute résolution de la dynamique à court terme des migrations verticales nycthémérales (MVN) du krill dans l'estuaire du Saint-Laurent est présenté. Il incorpore des mesures de transfert de masse sur la verticale à partir d'échosondages multifréquences couplés à l'échantillonnage des strates au filet à nappe et le suivi des mouvements verticaux individuels par des mesures de pigments stomacaux sur une période de 72 h. Des séries temporelles des patrons circadiens des vitesses verticales de migrations déterminées à l'aide d'un ADCP (« acoustic Doppler current profiler »; profileur de courant acoustique à effet Doppler) complètent les mésures sur une période allant jusqu'à 3 mois. L'ensemble du krill migre toujours rapidement et en synchronie jusqu'en surface lors du coucher du soleil. Peu de temps après l'ascension, du krill nourri commence à nager vers le bas, ce qui se poursuit avec une intensité notable jusqu'au milieu de la nuit. Il forme alors une couche acoustique de rétrodiffusion à sa profondeur diurne, ce qui engendre une distribution verticale nocturne bimodale, souvent accompagnée de densités acoustiques notables aux profondeurs intermédiaires, particulièrement au milieu de la nuit. Une réorganisation dans la partie supérieure de la colonne d'eau survient ensuite, vraisemblablement pour une dernière période d'alimentation avant l'aube. A l'aube, la masse de krill s'alimentant toujours dans la partie supérieure de la colonne d'eau nage en synchronie vers sa profondeur diurne. Ce comportement vertical nocturne asynchrone, conforme à l'hypothèse de faim-satiété de la MVN, s'est répété entre les mois d'août et d'octobre à deux années différentes, la synchronisation de la MVN dépendant de la durée du jour.

Published
2009

24. Contributions to passive acoustic oceanic tomography - inversion algorithms based on the marine mammals vocalizes

Author

Gervaise, Cedric, Bou Mansour, E., Vallez, Simon, Le Floch, H., Martin, A., Khenchaf, Ali, Simard, Y., Extraction et Exploitation de l'Information en Environnements Incertains (E3I2), École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne), and Ensta Bretagne, Stic Rems

Subjects
[INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, [INFO.INFO-TS] Computer Science [cs]/Signal and Image Processing, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, ComputingMilieux_MISCELLANEOUS, [SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience

Published
2005

25. Contributions to passive acoustic oceanic tomography – Inversion Algorithms based on Time Frequency Space Representation

Author

Gervaise, Cedric, Vallez, Simon, Bou Mansour, E., Martin, A., Khenchaf, Ali, Simard, Y., Extraction et Exploitation de l'Information en Environnements Incertains (E3I2), École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne), and Ensta Bretagne, Stic Rems

Subjects
[INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, [INFO.INFO-TS] Computer Science [cs]/Signal and Image Processing, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, ComputingMilieux_MISCELLANEOUS, [SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience

Published
2005

26. Contributions to Passive Acoustic Oceanic Tomography – Part II : Extraction of propagation features from single hydrophone measurement

Author

Gervaise, Cedric, Bou Mansour, E., Vallez, Simon, Le Floch, H., Martin, A., Khenchaf, Ali, Simard, Y., Extraction et Exploitation de l'Information en Environnements Incertains (E3I2), École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne), and Ensta Bretagne, Stic Rems

Subjects
[INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, [INFO.INFO-TS] Computer Science [cs]/Signal and Image Processing, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, ComputingMilieux_MISCELLANEOUS, [SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience

Published
2005

28. Contribution à la tomographie acoustique passive – algorithmes d'inversion temps-fréquence-espace MUSIC adaptés aux sources naturelles transitoires

Author

Gervaise, Cedric, Bou Mansour, E., Vallez, Simon, Le Floch, H., Martin, Arnaud, Khenchaf, Ali, Simard, Y., Extraction et Exploitation de l'Information en Environnements Incertains (E3I2), École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne), and Ensta Bretagne, Stic Rems

Subjects
[INFO.INFO-TS]Computer Science [cs]/Signal and Image Processing, [INFO.INFO-TS] Computer Science [cs]/Signal and Image Processing, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, ComputingMilieux_MISCELLANEOUS, [SPI.SIGNAL] Engineering Sciences [physics]/Signal and Image processing
Abstract

National audience

Published
2004

38. Collected reprints of the main contributed papers of EICHOANT program (Evaluation of Behaviour Influence on Fishery Biology and Acoustic Observations in Tropical Open Sea) presented during congresses from 1/1/87 to 4/30/90 = Compilation des principales communications du programme EICHOANT (Evaluation de l'Impact du Comportement en Halieutique et sur les Observations Acoustiques en Milieu Naturel Tropical) présentées à des congrès entre le 1/1/87 et le 30/4/90

Author

Simard, Y. and Gerlotto, François

Subjects
POISSON MARIN, VARIATION TEMPORELLE, GEOSTATISTIQUE, VARIATION SPATIALE, VARIOGRAMME, ECHOINTEGRATION, ANALYSE DE DONNEES
Abstract

L'applicabilité de la géostatistique pour l'analyse de données d'écho-intégration est explorée à l'aide de deux ensembles de données provenant des eaux côtières du nord de la Norvège et du Vénézuela. Les écarts aux conditions de stationnarité et les variations temporelles des structures spatiales sont examinées en portant une attention spéciale aux effets de : (1) l'utilisation des données brutes ou transformées en unités logarithmiques, (2) l'exclusion ou l'inclusion des séries de zéros, (3) différences jour/nuit dans les structures spatiales, (4) double échantillonnages et (5) différentes communautés de poissons. Tous ces facteurs affectèrent fortement la forme des variogrammes calculés, et conséquemment les estimations de biomasse qui en étaient reliées. L'utilisation de la géostatistique pour l'analyse des structures spatiales, l'estimation ou la cartographie de la biomasse en écho-intégration doit donc être effectuée avec précautions. Des recommandations sont suggérées et les aspects demandant plus de recherche sont soulevés. (Résumé d'auteur)

Published
1990

45. Use of a two-frequency algorithm to determine size and abundance of plankton in three widely spaced locations

Author

Mitson, R.B., Simard, Y., Goss, C., Mitson, R.B., Simard, Y., and Goss, C.

Abstract

The application of a two-frequency algorithm to the in situ estimation of large zooplankton is explored in an effort to use information from more than one acoustic frequency. To accomplish this, 38 and 120 kHz echo-sounders, found on most fisheries research vessels, were utilized. A two-frequency method using a highpass fluid sphere scattering model was employed to estimate the mean size (length) and the density per m3 of the dominant acoustic scatterers (mainly euphausiids and shrimps), by selected depth layer. Three locations were surveyed: the Gulf of St Lawrence, the Antarctic, and the Irish Sea. Ground-truth samples were collected from various plankton net systems, the catches being compared to the acoustic estimates. Results are discussed with regard to conditions that apply to the method, the ground-truth performance and the relative complexity of the zooplankton composition at the different study sites. The conclusion is that this method has provided satisfactory results but still has a capacity for refinement.

Published
1996

49. Use of a two-frequency algorithm to determine size and abundance of plankton in three widely spaced locations.

Author

Mitson, R. B., Simard, Y., and Goss, C.

Subjects
EUPHAUSIIDAE, SHRIMPS, PLANKTON, UNDERWATER acoustics, FISH populations, ZOOPLANKTON
Abstract

The application of a two-frequency algorithm to the in situ estimation of large zooplankton is explored in an effort to use information from more than one acoustic frequency. To accomplish this, 38 and 120 kHz echo-sounders, found on most fisheries research vessels, were utilized. A two-frequency method using a highpass fluid sphere scattering model was employed to estimate the mean size (length) and the density per m3 of the dominant acoustic scatterers (mainly euphausiids and shrimps), by selected depth layer. Three locations were surveyed: the Gulf of St Lawrence, the Antarctic, and the Irish Sea. Ground-truth samples were collected from various plankton net systems, the catches being compared to the acoustic estimates. Results are discussed with regard to conditions that apply to the method, the ground-truth performance and the relative complexity of the zooplankton composition at the different study sites. The conclusion is that this method has provided satisfactory results but still has a capacity for refinement. [ABSTRACT FROM PUBLISHER]

Published
1996
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