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Development of a new velocity measurement technique : the laser bessel velocimetry
No full textThe present thesis describes the design, construction and testing of a new velocity measurement optical technique system. The technique has similarities with the laser Doppler velocimetry (LDV) in that it uses scattered light detection, in order to measure one component of the velocity vector of moving flows or solid surfaces. It uses the fringes of a Bessel beam produced by an axicon to generate the measurement volume. This technique, which we call Laser Bessel velocimetry (LBV), is noninvasive and permits continuous velocity measurements of moving particles. The experimental measurement set-up including the laser source, the optical devices, a moving stage with known velocities, a photodetector to capture scattered light and signal processing and data acquisition components, was developed and used to provide a proof of concept of this new technique. The set-up was also tested with a commercial LDV system.
Two types of refractive linear axicons have been used to generate a Bessel type beam by illuminating the axicons with blue and red collimated and coherent laser light of dissimilar wavelengths, λ. The linear axicons offer the advantage of simplicity. The software tools for measurements, acquisition and analysis of the data are developed using NI Labview and MATLAB. Results from both theoretical simulation and experimental measurements are presented and compared
An analysis of physical activity levels of children following the balanced school day schedule
No full textBackground: Physical activity is a key determinant of children’s health. However, increasingly children are not attaining adequate amounts of physical activity. Children spend a considerable amount of time at school and school-based physical activity can significantly contribute to total daily physical activity achieved by children. Specifically, recess time can significantly contribute to a child’s daily opportunity to attain the recommended 60 minutes of physical activity per day. In this thesis, I assessed the impact of block scheduling on physical activity levels during recess for children in grades 3 and 6. More specifically, I examined the impact of time of day (am vs. pm) and season (fall vs. winter) on levels of recess-based physical activity among children using the “Balanced School Day” schedule.
Methods: Data were collected at a school using the Balanced School Day schedule over five consecutive days during fall and winter in a school from a community in northern Ontario. Children wore the Yamax SW-200 pedometer and a segmented data collection approach to assess step counts during ‘class-time’ and ‘recess-time’ was used.
Results: Seventy-eight students participated in this study. Average daily steps were higher in the fall compared to the winter. There were no meaningful differences in the number of steps taken when considering time of day. Boys accumulated significantly more steps than girls for total recess steps regardless of season. Grade 3 students experienced the greatest decrease in steps seasonally.
Conclusions: As a result of this study, we have reaffirmed that children are not maximizing opportunities for physical activity during the school day. In general, lower step counts are noted among girls and grade 6 students. We can also conclude that the recess schedule (i.e. morning vs.
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afternoon) does not affect physical activity during recess in children using the BSD; however, there is a seasonal influence. All children were less active in the winter recess when compared to the fall and this was particularly accentuated among the younger participants
Teaching English for Academic Preparation through the “communitarian self” concept as an aspect of the theory of objectification/subjectification: learners’ development of linguistic, interpersonal and conceptual skills
No full textOne of the most important areas of English as a foreign language teaching is English for Specific
Purposes (ESP). ESP is a special branch of English Language Teaching which focuses on the
learners’ specific needs and the learning environment. The learners’ needs and requirements are
in constant change and their expectations increase especially when they are learning for
professional purposes. What is more, our main interest is focused on English for Academic
Preparation (EAP) learners, whose needs are quite different as they intend to enrol in different
academic programs at the university level. Moreover, each discipline has its own and specific
terminology and jargon. Indeed, instructors teaching EAP program should cover a wide range of
topics and content through the subject-matter. The task, then, becomes difficult and challenging.
Studies have indicated that learners are not playing an active role within the ESP learning
process, in general, and in EAP program in particular. Interaction between the learners
themselves and the instructors are absent. The aim of the present doctoral research project is to
develop a model where the concept of “Communitarian Self” will be utilized as a pedagogical
tool in teaching EAP to improve the dynamics of the social practices taking place in the
classroom learning context. This study will show that the tool provides learners an interesting
and helpful learning community environment in which socio-cultural interaction; and exchange
and critical thinking take place. Based on communication, autonomy, cooperation and
collaboration among the other social individuals and the learners themselves, this tool
encourages the whole community’s interaction and negotiation of meaning in a social and
cultural environment. This tool will be examined to what extent it can help EAP learners become
active participants in their activities and contribute to the improvement of their communicative
skills, cognitive skills and comprehension and understanding in a socio-cultural environment.
Findings show that the tool impacts learning to a great extent. Recommendations for the
teaching/learning context and future are made
The impact of induced emotion on language
No full textThrough the investigation of the relationship between linguistics and cognition, it has been discovered that language differences can be found within individuals based on their current affective state. The current study examined whether the three dimensions of language (pleasantness, activation, and imagery) are evident in the language of participants after affective states have been manipulated. 60 Laurentian students were assigned to one of the three group conditions – positive exposure, negative exposure, or control. Participants were also divided by sex between the three groups. Participants were then asked to write a passage describing a personal event. Passages were examined using the Dictionary of Affect in Language (DAL) to determine the emotionality of the passages. Results were analyzed by conducting a 2x3 factorial MANOVA between subjects; the results failed to support the main hypothesis that the dimensions of language are impacted by emotion. However, results did indicate that females used language with more imagery and detail. Additionally, results indicated that event recall negativity was affected by emotion. Limitations, future directions, and implications are discussed.Honours essa
Application of physical properties measurements to lithological prediction and constrained inversion of potential field data, Victoria Property, Sudbury, Canada.
No full textIn recent years the number of near-surface deposits has decreased significantly; consequently, exploration companies are transitioning from surface-based exploration to subsurface exploration. Geophysical methods are an important tool to explore below the surface. The physical property data are numerical data derived from geophysical measurements that can be analyzed to extract patterns to illustrate how these measurements vary in different geological units. Having knowledge of links between physical properties and geology is potentially useful to obtain more precise understanding of subsurface geology.
Firstly, down-hole density, gamma radioactivity, and magnetic susceptibility measurements in five drillholes at the Victoria property, Sudbury, Ontario were analyzed to identify a meaningful pattern of variations in physical property measurements. The measurements grouped into distinct clusters identified by the fuzzy k-means algorithm, which are termed ‘physical log units’. There was a meaningful spatial and statistical correlation between these physical log units and lithological units (or groups of lithological units), as classified by the geologist. The existence of these relationships suggests that it might be possible to train a classifier to produce an inferred function quantifying this link, which can be used to predict lithological units and physical units based on physical property data. A neural network was trained from the lithological information from one hole, and was applied on a new hole with 64% of the rock types being correctly classified when compared with those logged by geologists. This misclassification can occur as a result of overlap between physical properties of rock types. However, the predictive accuracy in the training process rose to 95% when the network was trained to classify the physical log units (which group together the units with overlapping properties). Secondly, lithological prediction based on down-hole physical property measurements was extended from the borehole to three-dimensional space at the Victoria property. Density and magnetic susceptibility models were produced by geologically constrained inversion of gravity and magnetic field data, and a neural network was trained to predict lithological units from the two physical properties measured in seven holes. Then, the trained network was applied on the 3D distribution of the two physical properties derived from the inversion models to produce a 3D litho-prediction model. The lithologies used were simplified to remove potential ambiguities due to overlap of physical properties. The 3D model obtained was consistent with the geophysical data and resulted in a more holistic understanding of the subsurface lithology. Finally, to extract more information from geophysical logs, the density and gamma-ray response logs were analyzed to detect boundaries between lithological units. A derivative method was successfully applied on the down-hole logs, and picked the boundaries between rock types identified by geologists as well as additional information describing variation of physical properties within and between layers not identified by the geologist
Visual art discourses as rhetoric: exploring the colonial creation of the Canadian Northwest Passage
Get PDFIn the 1920s Canadian colonialism became domesticated; a political and
economic change was publically presented and mystified through the creation of a
professedly nationalist landscape mythology. In the words of A.Y. Jackson, Canada
needed “a new, modern landscape art tradition, for a new modern nation.”
According to Jonathan Bordo, such colonial myths of origins have served to supplant
aboriginal peoples by establishing a precolonial belief of “ terra nullius,” which was later
enforced by the removal of visual and cultural references to aboriginal cultures and
peoples, rendering their historic and contemporary presence invisible to colonizers.
In Canada, however, a second modern art tradition interceded. Even as the Group of
Seven’s interpretation of the Canadian landscape became definitive, Robert Flaherty’s
Nanook of the North rose to acclaim as well. Flaherty’s devotion to the idea (also borne
of Europe) that morally uncorrupted pre-modern landscape essentialist communities
existed in protective isolation would re-implant certain aboriginal peoples back into the
Canadian landscape imaginary, but on particularly disadvantageous terms.
Farley Mowat’s mid-Century reconfiguration of these two landscape art traditions as rhetoric continues to define Canadian understandings of the political relations
between aboriginal and non-aboriginal peoples, as well as the Canadian understanding
of political claims and relations between mainstream Canadians and their
government(s) and internally colonized peoples.
Since the closure of the two historic economic engines along the Northwest
Passage, sealing and the cod fishery, in the mid 1980’s and early 1990s respectively,
the turn to cultural and eco-tourism based economies has resulted in the wide promotion of images founded in Mowat’s reimagined history of Inuit and
Newfoundlanders. Cultural and eco-tourism have, in turn, led to a drive to conformity
with Mowat’s visions in Northwest Passage communities, which have resulted in both
processes of cultural selection, and instances of resistance.
As the Canadian administrative state positions itself with regard to melting
Northwest Passage, it behooves those wishing to understand the politics pertaining to
the Northwest Passage to analyze the rhetoric of the images underlying and
promulgated during these international negotiations
Cognitive consequences of sleep deprivation, shift work, and heat exposure for underground miner
Get PDFThe extent to which an underground miner’s alertness is influenced by sleep deprivation, shift work, and working in elevated temperatures is currently unknown. Actigraphy and psychomotor vigilance data were collected from nineteen underground miners over 28 consecutive days. Core body temperature data was also gathered during four scheduled work shifts. Participants experienced shortened sleep durations and poor sleep efficiency throughout the study. Significant increases in reaction time occurred over the course of night shifts, a decline that was not observed during day shifts. A strong, negative correlation between core body temperature and reaction time was present throughout day shifts but did not appear during night shifts. Poor sleep and altered circadian rhythms appear to negatively affect the alertness of participants during work times. An inadequate adaptation to night work schedules may be indicated by the poor alertness and absent relationship between core body temperature and performance observed during night shifts
