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Application of neuroergonomics in the industrial design of mining equipment.
No full textNeuroergonomics is an interdisciplinary field merging neuroscience and ergonomics to optimize performance. In order to design an optimal user interface, we must understand the cognitive processing involved. Traditional methodology incorporates self-assessment from the user. This dissertation examines the use of neurophysiological techniques in quantifying the cognitive processing involved in allocating cognitive resources. Attentional resources, cognitive processing, memory and visual scanning are examined to test the ecological validity of theoretical laboratory settings and how they translate to real life settings. By incorporating a non-invasive measurement technique, such as the quantitative electroencephalogram (QEEG), we are able to examine connectivity patterns in the brain during operation and discern whether or not a user has obtained expert status. Understanding the activation patterns during each phase of design will allow us to gauge whether our design has balanced the cognitive requirements of the user
Object distance measurement using a single camera for robotic applications
No full textVisual servoing is defined as controlling robots by extracting data obtained from
the vision system, such as the distance of an object with respect to a reference frame, or the length and width of the object. There are three image-based object distance
measurement techniques: i) using two cameras, i.e., stereovision; ii) using a single
camera, i.e., monovision; and iii) time-of-flight camera.
The stereovision method uses two cameras to find the object’s depth and is highly
accurate. However, it is costly compared to the monovision technique due to the higher
computational burden and the cost of two cameras (rather than one) and related
accessories. In addition, in stereovision, a larger number of images of the object need to
be processed in real-time, and by increasing the distance of the object from cameras, the
measurement accuracy decreases. In the time-of-flight distance measurement technique,
distance information is obtained by measuring the total time for the light to transmit to
and reflect from the object. The shortcoming of this technique is that it is difficult to
separate the incoming signal, since it depends on many parameters such as the intensity
of the reflected light, the intensity of the background light, and the dynamic range of the
sensor. However, for applications such as rescue robot or object manipulation by a robot
in a home and office environment, the high accuracy distance measurement provided by
stereovision is not required. Instead, the monovision approach is attractive for some
applications due to: i) lower cost and lower computational burden; and ii) lower
complexity due to the use of only one camera.
Using a single camera for distance measurement, object detection and feature
extraction (i.e., finding the length and width of an object) is not yet well researched and there are very few published works on the topic in the literature. Therefore, using this
technique for real-world robotics applications requires more research and improvements.
This thesis mainly focuses on the development of object distance measurement
and feature extraction algorithms using a single fixed camera and a single camera with
variable pitch angle based on image processing techniques. As a result, two different
improved and modified object distance measurement algorithms were proposed for cases
where a camera is fixed at a given angle in the vertical plane and when it is rotating in a
vertical plane. In the proposed algorithms, as a first step, the object distance and
dimension such as length and width were obtained using existing image processing
techniques. Since the results were not accurate due to lens distortion, noise, variable light
intensity and other uncertainties such as deviation of the position of the object from the
optical axes of camera, in the second step, the distance and dimension of the object
obtained from existing techniques were modified in the X- and Y-directions and for the
orientation of the object about the Z-axis in the object plane by using experimental data
and identification techniques such as the least square method.
Extensive experimental results confirmed that the accuracy increased for
measured distance from 9.4 mm to 2.95 mm, for length from 11.6 mm to 2.2 mm, and for
width from 18.6 mm to 10.8 mm. In addition, the proposed algorithm is significantly
improved with proposed corrections compared to existing methods. Furthermore, the
improved distance measurement method is computationally efficient and can be used for
real-time robotic application tasks such as pick and place and object manipulation in a
home or office environment
Illustrations de la pensée critique dans les pratiques éducatives d'enseignants d'éducation physique et santé (ÉPS): une piste pour un développement de la pensée critique en formation initiale. (chapitre 1)
No full textChronic nitrogen and nutrient deposition impacts on community structure and abundance of bacteria, fungi, and CH4 cycling prokaryotes in a northern peat bog
No full textAnthropogenic nitrogen (N) deposition may threaten peatland carbon storage capabilities. Increased deposition has been linked to subsequent plant community shifts and increased decomposition rates, potentially via the disruption of natural microbial communities. By examining peat soils from randomized, replicated treatment plots in a long-term simulated chronic N deposition experiment at the Mer Bleue Bog in Eastern Ontario, Canada, my objective was to characterize how increased deposition impacts community structure and abundance of broad groups of microbial communities, and specific CH4 cycling prokaryotes. Using fingerprinting approaches and qPCR of SSU rRNA and other functional genes, my data show that with increasing nutrient loading the bacterial and fungal community structure changed. Along the same gradient methanogen abundance decreased, however there were no corresponding changes in methanotroph community structure or abundance. My results provide new insights on the possible causes of higher CO2 and CH4 effluxes seen in situ following chronic nutrient loading
Les erreurs articulatoires chez les enfants qui fréquentent la maternelle (3 ans 10 mois à 4 ans 10 mois) dans un conseil scolaire franco-ontarien
No full text
Une photographie critique de l'éducation physique et sportive du Togo
No full textAu Togo, tout comme dans la plupart des pays africains, l'éducation physique et sportive (ÉPS) est une discipline scolaire mentionnée dans les curricula de formation. À partir de la lecture de ces curricula et de la nature réelle de l'observation du déroulement de l'ÉPS à l'École, les auteurs tentent de présenter nature réelle, de même que la fonction de cette discipline scolaire du système éducatif togolais. Des propositions sont faites dans la perspective d'une ÉPS plus éducative
Activité antimicrobienne de produits naturels originaires du Nord de l’Ontario
No full textLa multirésistance microbienne pose de grands problèmes au niveau de la santé publique. En fait, il ne reste que peu d’agents antimicrobiens effectifs contre certains microbes multirésistants. Les scientifiques sont donc à la recherche de nouveaux produits antimicrobiens. Cette recherche a évalué l’activité antimicrobienne de substances naturelles provenant de plantes originaires du Nord de l’Ontario. Vingt-cinq extraits, dix fractions et dix-neuf composés purs ont été testés contre des microbes pathogènes, soientEscherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa et Candida albicans. L’activité antimicrobienne des produits naturels a été observée en utilisant la technique de dosage sur microplaque qui emploie le résazurin, et la concentration minimale inhibitrice (CMI) des produits a été déterminée. Afin de démontrer que l’activité antimicrobienne des substances naturelles n’était pas limitée à une seule espèce, certains composés purs ont été testés contre des microbes secondaires, soient Streptococcus lactis, Mycobacterium phlei et Schizosaccharomyces octosporus. Quatre extraits de plantes (Chimaphila umbellata, Betula papyrifera, Rhus typhina et Fraxinus pennsylvanica) et six composés purs (acide gallique, éthyle gallate, acide cafféique, acide synapique, acide gentisique et acide chlorogénique) ont démontré une activité antibactérienne ou antifongique. Ces résultats démontrent que ces produits naturels ont le potentiel d’être développés en nouveaux agents antimicrobiens