496 research outputs found
Lisa J. Reimer's Quick Files
No full textThe Quick Files feature was discontinued and it’s files were migrated into this Project on March 11, 2022. The file URL’s will still resolve properly, and the Quick Files logs are available in the Project’s Recent Activity
Lisa J. Reimer's Quick Files
No full textThe Quick Files feature was discontinued and it’s files were migrated into this Project on March 11, 2022. The file URL’s will still resolve properly, and the Quick Files logs are available in the Project’s Recent Activity
Lisa J. Reimer's Quick Files
No full textThe Quick Files feature was discontinued and it’s files were migrated into this Project on March 11, 2022. The file URL’s will still resolve properly, and the Quick Files logs are available in the Project’s Recent Activity
Water Vapour Distribution in HT-PEFC - A Pragmatical Approach for CFD Simulations
No full textAbstract for poster presentationWater vapour distribution in HT-PEFC a pragmatical approach for CFD simulationsUwe Reimer*1, Dieter Froning1, Werner Lehnert1,21 Forschungszentrum Jülich GmbH, Institute of Energy and Climate Research, Electrochemical Process Engineering, 52425 Jülich, Germany2 Modeling in Electrochemical Process Engineering, RWTH Aachen University, Aachen, Germany*Presenting author, email: [email protected], Tel.: +49 2461-3537In polymer electrolyte fuel cells water is produced within the cathode catalyst layer. This water is leaving the fuel cell both through anode and cathode gas channel. The distribution of water to anode and cathode side is difficult to predict. It depends on material properties of membrane, catalyst layers, microporous layers and gas diffusion layers [1,2]. Additionally, the dynamics of evaporation and condensation which in turn are strongly influenced by flow configuration, local current density and local temperature have to be taken into account in order to obtain correct values for mass flow and local gas concentration in CFD simulations [1].For HT-PEFCs operated at 160 °C the produced water is in the gas state. Recently, a detailed model for vapour distribution was published [3]. In order to obtain a model with little computational demand a model for water distribution is developed. The basic assumption is that water evaporation is very fast and the final distribution between cathode and anode depends mainly on the mass flow in the gas channels. In order to reach the anode water has to pass through the membrane. This process is captured by including a resistance term in the model. This resistance term is fitted to experimental data. The fitted value for the resistance term is rather small at ‘normal’ operation conditions and leads to a difference of 10 % compared to the model which only considers the mass flow on anode and cathode. Therefore, the presented model might be a practical approach to include the effect of water vapour distribution to cathode and anode as a rough estimation. This is important because local current density and voltage are depending on correct values for local concentrations. The experiment was carried out with a HT-PEFC single cell with PBI/ phosphoric acid membrane operated at 160 °C and ambient pressure with air and hydrogen. The CFD model is based on a previously published one [4] with the extension of water distribution [5]. The flow field geometry is a threefold meander with an active area of 17 cm2.[1] A. Z. Weber, R. L. Borup, R. M. Darling, P. K. Das, T. J. Dursch, W. Gu, D. Harvey, A. Kusoglu, S. Litster, M. M. Mench, R. Mukundan, J. P. Owejan, J. G. Pharoah, M. Secanell and I. V. Zenyuk, J. Electrochem. Soc., 161 (2014), F1254 [2] A. Thomas, G. Maranzana, S. Didierjean, J. Dillet, O. Lottin, Int. J. Hydrogen Energy, 39 (2014), 2649[3] T. J. Kazdal, S. Lang, F. Kühl, M. J. Hampe, J. Power Sources, 249 (2014), 446[4] M. Kvesić, U. Reimer, W. Lehnert, D. Froning, L. Lüke, D. Stolten, Int. J. Hydrogen Energy, 37 (2012), 2430[5] A. Kind, Masterthesis, FH Aachen, Jülich/ Aachen, Germany (2014
LETTER TO THE EDITOR REGARDING: EVOLVING BUSINESS MODELS IN ORTHOTICS BY SCHNEIDER, N.
No full textThe purpose of this letter is to continue the dialogue regarding the paper "Evolving business models in Orthotics" in the Canadian Prosthetics & Orthotics Journal Volume 4, Issue2, No.3, 2021. In it we present the perspective of the current Alberta Association of Orthotists and Prosthetists (AAOP) and provide additional context and information on historical events. Finally, we provide additional clarity on how costing is approached in the Province of Alberta (Canada) and the purported inequity in compensation between the two disciplines.
Article PDF Link: https://jps.library.utoronto.ca/index.php/cpoj/article/view/38313/30512
How To Cite: Pardy C, Scott S, Barnert J, Reimer C. Letter to the editor regarding: Evolving business models in orthotics by Schneider N. Canadian Prosthetics & Orthotics Journal. 2022; Volume 5, Issue 2, No.5. https://doi.org/10.33137/cpoj.v5i2.38313
Corresponding Author: Connor Pardy, M.Sc., CPO
Alberta Orthotic and Prosthetic Centre, Calgary, AB, Canada.
Past-President of the Alberta Association of Orthotists and Prosthetists
E-Mail: [email protected]
ORCID ID: https://orcid.org/0000-0003-4475-977
Malaria transmission dynamics surrounding the first nationwide long-lasting insecticidal net distribution in Papua New Guinea
No full textThe major malaria vectors of Papua New Guinea exhibit heterogeneities in distribution, biting behaviour and malaria infection levels. Long-lasting, insecticide-treated nets (LLINs), distributed as part of the National Malaria Control Programme, are the primary intervention targeting malaria transmission. This study evaluated the impact of LLINs on anopheline density, species composition, feeding behaviour, and malaria transmission.; Mosquitoes were collected by human landing catch in 11 villages from East Sepik Province and Madang Province. Mosquitoes were collected for 3 years (1 year before distribution and 2 years after), and assayed to determine mosquito species and Plasmodium spp. infection prevalence. The influence of weather conditions and the presence of people and animals on biting density was determined. Determinants of biting density and sporozoite prevalence were analysed by generalized estimating equations (GEE).; Mosquito biting rates and entomological inoculation rates decreased significantly after the distribution. Plasmodium falciparum and P. vivax sporozoite prevalence decreased in year 2, but increased in year 3, suggesting the likelihood of resurgence in transmission if low biting rates are not maintained. An earlier shift in the median biting time of Anopheles punctulatus and An. farauti s.s. was observed. However, this was not accompanied by an increase in the proportion of infective bites occurring before 2200 hours. A change in species composition was observed, which resulted in dominance of An. punctulatus in Dreikikir region, but a decrease in An. punctulatus in the Madang region. When controlling for village and study year, An. farauti s.s., An. koliensis and An. punctulatus were equally likely to carry P. vivax sporozoites. However, An. punctulatus was significantly more likely than An. farauti s.s. (OR 0.14; p = 0.007) or An. koliensis (OR 0.27; p < 0.001) to carry P. falciparum sporozoites.; LLINs had a significant impact on malaria transmission, despite exophagic and crepuscular feeding behaviours of dominant vectors. Changes in species composition and feeding behaviour were observed, but their epidemiological significance will depend on their durability over time
Observation of strongly entangled photon pairs from a nanowire quantum dot
No full textA bright photon source that combines high-fidelity entanglement, on-demand generation, high extraction efficiency, directional and coherent emission, as well as position control at the nanoscale is required for implementing ambitious schemes in quantum information processing, such as that of a quantum repeater. Still, all of these properties have not yet been achieved in a single device. Semiconductor quantum dots embedded in nanowire waveguides potentially satisfy all of these requirements; however, although theoretically predicted, entanglement has not yet been demonstrated for a nanowire quantum dot. Here, we demonstrate a bright and coherent source of strongly entangled photon pairs from a position-controlled nanowire quantum dot with a fidelity as high as 0.859±0.006 and concurrence of 0.80±0.02. The two-photon quantum state is modified via the nanowire shape. Our new nanoscale entangled photon source can be integrated at desired positions in a quantum photonic circuit, single-electron devices and light-emitting diodes.QN/Quantum NanoscienceApplied Science
Self-reported and observed risky driving behaviors among frequent and infrequent cell phone users
No full textThe apparently higher crash risk among individuals who use cell phones while driving may be due both to the direct interference of cell phone use with the driving task and tendencies to engage in risky driving behaviors independent of cell phone use. Measurements of actual highway driving performance, self-reported aberrant driving behaviors as measured by the Manchester Driver Behavior Questionnaire (DBQ), and attitudes toward speeding, passing behaviors and relative concern about being involved in a crash were assessed. Individuals who reported frequently using cell phones while driving were found to drive faster, change lanes more frequently, spend more time in the left lane, and engage in more instances of hard braking and high acceleration events. They also scored higher in self-reported driving violations on the DBQ and reported more positive attitudes toward speeding and passing than drivers who did not report using a cell phone regularly while driving. These results indicate that a greater reported frequency of cell phone use while driving is associated with a broader pattern of behaviors that are likely to increase the overall risk of crash involvement. (C) 2012 Elsevier Ltd. All rights reserved
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