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Embryonic thermal stress and its effect on the stress response during embryogenesis and early life stages in yellow perch (Perca flavescens)
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Science in Biology, University of Regina. ix, 71 p.Temperature is one of the most influential abiotic factors that affects every aspect of
biology. Currently, the combination of climate change, and the widespread use of once-through
cooling systems in industrial facilities, has resulted in an increase in thermal plume production
and temperature variability in aquatic environments. Changes in the thermal environment can
have drastic changes on fish biology, due to their ectothermic nature, especially during key
stages of development when the formation of vital structures and organogenesis is occurring.
Less focus has been put on examining the heat shock response (HSR) in cool water, spring
spawners such as yellow perch (Perca flavescens). Yellow perch are an economically, culturally,
and recreationally important cool water species found throughout North America. Further
research examining how the nature of the HSR changes throughout development, and how the
thermal environment during embryogenesis impacts this response is required. My research aimed
to determine how incubation temperature influences the HSR and thermal tolerance in yellow
perch. Fish were incubated at 12, 15, and 18℃, during embryogenesis. At key developmental
timepoints, fish were exposed to a 2 h heat shock (HS) of + 3, 6, or 9℃. mRNA transcript levels
of heat shock proteins (HSPs) were quantified using RT-qPCR. In the Year 2 experiment, posthatch
fish were subjected to critical thermal maximum (CTmax) trials as a proxy to measure
thermal tolerance. HSP transcript results showed that the nature of the HSR changes throughout
development and continues to change in post-hatch fish. Incubation temperature also appeared to
alter the nature of this response, with embryos incubated at 12 and 18℃ displaying significantly
upregulated levels of hsp70-1, hsp70-2, and hsp47, after sham treatments and most HS
treatments, while the 15℃ fish typically only displayed upregulations of HSP transcripts at
higher magnitude HS treatments (+6 or 9℃). This suggests that exposure to temperatures near
optimal limits could have resulted in a hormetic effect. This hormetic effect resulted in the
lowering of the induction threshold that triggers a HSR in the 12 and 18℃ groups, relative to the
15℃ post-hatch fish. Overall, this research showed that the nature of the HSR changes
throughout development in yellow perch and suggests that the thermal environment during
development can have a cascading effect on the HSR in fish that persists well after
embryogenesis.Studentye
Optimal pricing and control strategy for electric vehicle charging stations
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Electronic Systems Engineering, University of Regina. xviii, 120 p.The increasing popularity and number of electric vehicles (EVs) globally have resulted
in a growing demand for efficient, affordable and convenient electric vehicle
charging station (EVCS) infrastructure. However, the development and implementation
of this infrastructure involve various challenges, such as EV battery and charging
station parameters, transportation and power system congestion, user satisfaction,
and station operators' profitability.
This study proposes an optimized pricing and control strategy for EVCSs, considering
the integrated operation of the transportation network and the power distribution
system. This model offers a competitive pricing strategy that accounts for both
competitive and non-competitive charging demand. Additionally, the model explores
the recursive impact of queuing processes and entry control schemes on charging
demand, aiming to reduce congestion, enhance user satisfaction, and maintain an
affordable charging pricing strategy while ensuring profitability and stability in the
power system.
Simulation results show that, by using the optimal pricing, the EVCS can reduce
the peak demand and generate 47% more profit than the fixed pricing. By implementing
the proposed optimal variable pricing and control strategy, the EVCS operator
can provide the highest quality of service while still maintaining profitability.Studentye
Developing a new approach for estimating oil recovery during Steam-Assisted-Gravity-Drainage (SAGD)
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Petroleum Systems Engineering, University of Regina. xiv, 115 p.Canada possesses a substantial abundance of heavy oil and bitumen reserves. Given the continuously growing energy requirements, in conjunction with economic factors and expanding environmental issues, it becomes crucial to employ modern and economically viable techniques for extracting these subsurface resources. These methods not only demonstrate alignment with present requirements but also contribute to the long-term sustainability of the heavy oil business. Among the array of thermal procedures available, Steam-Assisted Gravity Drainage (SAGD) emerges as a highly promising approach for attaining substantial oil recovery.
Despite the practicality of this technique and extensive research dedicated to it, there exists a notable gap in the availability of robust, reliable, and straightforward mathematical models that can accurately estimate oil production rates, steam usage, and recovery, including the rising phase of oil production. Existing commercial software solutions often require engineers to input extensive reservoir property information, which may not be readily accessible at the early stages of projects.
The present study discusses the introduction of a semi-numerical model aimed at optimizing the estimation of oil production by utilizing key reservoir properties. The model employs an exponential function to represent both the rising and expansion phases of the steam chamber. Through rigorous testing and comparison with an experimental study and two other existing models, this new approach has demonstrated its ability to estimate the real SAGD process's oil production and steam interface with greater accuracy. The success of this model underscores its potential as a valuable tool for the industry, bridging the existing gaps and contributing to the efficient utilization of Canada's heavy oil resourcesStudentye
Unprecedented preservation of soft tissues and organic matter in fossils characterized by synchrotron radiation techniques
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Science in Physics, University of Regina. xvi, 126 p.Fossilization is a rare process. Many orders of magnitude rarer is fossilization of “lifelike”
soft tissues or original organic molecules, as compared to mineralized components
such as bones and teeth. To probe for these extraordinary structures, a useful tool
that can be employed is synchrotron radiation — extremely intense photons that can
analyze complex heterogeneous samples with unmatched resolution, signal-to-noise
ratios, and acquisition times. Synchrotron radiation has revolutionized palaeontology
research, challenging conventional limits of taphonomy, the study of decay and
fossilization, and providing abundant information about ancient life.
In this thesis I will discuss the application of synchrotron radiation techniques
using the Canadian Light Source in search of exceptional preservation in fossils. This
will include techniques such as computed tomography, X-ray fluorescence, X-ray absorption
spectroscopy, infrared spectroscopy, as well as conventional techniques such
as scanning electron microscopy. The highlights of the research include: finding remnants
of preserved organic chitin in a beetle from Baltic amber, which is the oldest
and most well preserved for its age chitin ever reported in a fossil beetle; and finding
angiogenic blood vessels preserved in a fractured rib bone from Tyrannosaurus rex,
where combining high resolution three-dimensional modeling and chemical analysis
of dinosaur blood vessels has not been described before in literature. I show how
the use of several in situ, minimally destructive techniques on a single sample can
be compared to provide a thorough analysis of fossils and confirm the presence of
endogenous molecules and soft tissue structures.Studentye
Efficient coverage path planning and navigation of mobile farming robots
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Industrial Systems Engineering, University of Regina. xix, 150 p.Autonomous farming uses technologies such as robotics and artificial intelligence to
automate agricultural operations, reduce labor requirements, and improve productivity.
With a shortage of skilled labor in many parts of the world and increasing demand for food
due to population growth, autonomous farming can help farmers increase efficiency,
manage larger farms, and improve crop yields and profitability. Furthermore, autonomous
farming technologies can lead to improved environmental sustainability by reducing the
use of pesticides and fertilizers through targeted and precise application. Mobile robots,
such as self-driving tractors, are increasingly being used to automate various agricultural
operations such as planting, spraying, and harvesting using advanced algorithms and
sensors. The navigation stack, consisting of a set of algorithms and software tools for
mobile robot navigation and path planning, is a critical component of autonomous farming.
This work presents algorithms for coverage path planning, line-following control, and local
navigation used in the navigation stack of a mobile robot, enabling it to operate safely and
accurately, thus increasing efficiency and decreasing costs in farming operations.
Coverage path planning (CPP) is an essential component of autonomous farming that
enhances the efficiency of agricultural tasks. It provides benefits in terms of cost, time, and
quality of coverage. Coverage path planning refers to the process of generating an
uninterrupted, collision-free path for a mobile robot to cover a designated area of interest.
The aim of this work is to reduce the time and cost of agricultural operations by creating
an optimal coverage path using a graph-based representation of the field. The proposed
technique is compared to other existing techniques, and it is demonstrated that the proposed
technique generates a coverage path with shorter traveled distance (less overlapping) and
fewer turns.
The mobile robot should be capable of following the coverage path generated for a field.
The coverage path in agricultural applications includes lots of back-and-forth straight-line
motions. Therefore, an efficient control approach is required to achieve and follow desired
straight lines on the coverage path precisely (to avoid overlaps and skipped areas) and in a
time and cost efficient manner. A time-varying model predictive control (MPC) has been
designed to determine the appropriate steering angle of a mobile robot for line-following
control. To evaluate the performance and efficiency of the designed time-varying MPC
technique, it has been compared with a proportional control technique as a common control
method for line-following problems. The time-varying MPC proves to outperform the
proportional controller in terms of performance and cost.
The coverage path in a field is a global path, which is generated based on a prior knowledge
of the field and obstacles. However, if anything changes in this a priori known map of the
field, motion plans need to change accordingly, which brings out the notion of local motion
planning and navigation around obstacles. In this work, a human-analogous learning
technique has been proposed that can learn from a human operator trained in a simulated
environment under a learning-by-doing paradigm. A human-in-the-loop simulator, utilized
as the training environment for sensor-based motion planning, is developed. A neurofuzzy-
based steering algorithm is derived from data collected from a trained human
operator. The simulation results are compared to that cited in literature. The proposed
algorithm generates superior steering without the need to setting up a cost function and
tuning its parameters to generate an efficient local path.Studentye
Surface electromyography signal classification using SFDN+DNN for hand gesture recognition
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Industrial Systems Engineering, University of Regina. xiv, 96 p.In this thesis, a novel Deep Learning approach to classify the Surface Electromyography (SEMG) signals for hand movement recognition is presented and compared to the other approaches in the literature. EMG or muscle’s cells electrical activity are the electrical signals that are carried from the brain to the muscles through the spinal cord. These signals can be recorded and used to measure the activity of muscles. The concept is to measure the signals of different movements for healthy individuals, classify and train the signals, and use the trained model to predict the movements of individuals suffering from disability. The classifier used in this thesis is a Time Wrapped CNN+LSTM. The contribution of this research is to predict the hand movements (hand gestures) with a very high accuracy in order to enhance the efficiency of mechanical prosthetic hands and mimic the natural hand movement. To ensure the highest performance, the dataset is pre-processed using Smoothing (noise reduction), Filling Outliers (dimension reduction), Detrending (feature selection) and Normalizing. As a result, the novel method is called SFDN+DNN. There are many complex and developed prostheses in the market. However, the bottleneck to improve the capabilities of the prostheses to a quasi-real-hand level is still a big challenge. In this thesis a thorough literature review of advancements in EMG signal classification and the history of prosthetic hands are presented and some significant achievements are highlighted. Secondly the novel method to classify the SEMG signals is presented and evaluated using three benchmark hand SEMG datasets in the literature, which are the UCI Repository SEMG dataset, the Ninapro dataset and the Mendeley dataset. The datasets are also tested using some conventional machine learning algorithms such as KNN, SVM, Decision Tree, Random Forest, Naïve Bayes, Multi-nominal Logistic Regression, XGBoost and Multi-Layer-Perceptron, to illustrate the power of classification of our proposed method compared to these algorithms. Finally, the classification accuracy of the proposed method is compared to some of the most up-to-date techniques. The obtained results indicates that the DNN classifier can achieve a higher classification accuracy compared to the state-of-the-art methods in the literature. The classifier was able to reach the accuracies of 99.63%, 95.56% and 96.14%, for the UCI SEMG dataset, the NinaPro DB6 dataset and the Mendeley SEMG dataset respectively.
While the best claimed accuracy for these datasets in the literature, to the best knowledge of the author, was 99.49%, 93.7% and 89.5%, for the UCI SEMG dataset, the NinaPro DB6 dataset and the Mendeley SEMG dataset respectively.
The contributions of this research are as follows:
Inferring the hand movements as sequential, and time series classification. Low computation cost and the ability for learning online (end-to-end system), which is a significant advantage compared to the offline conventional methods, and substantially, reaching one of the highest classification accuracies in the literature, with acceptable results for designing real prosthetic hands.Studentye
An evaluation of the temporal and spatial evolution of waste facilities using a simplified spatial distance analytical framework
No full textThis is the accepted version of the original article available at https://doi.org/10.1016/j.envdev.2023.100820. © 2023 Published by Elsevier Ltd.
Accepted article is CC BY-NC-ND.This study proposed a simplified GIS-based decision support tool to examine the temporal and spatial evolution of waste facilities at a regional level. The key objective is to examine the geospatial distribution of landfills and transfer stations in Saskatchewan, Canada, from 2018 to 2020 based on changes in Euclidean distance computed by both the Central Feature (CF) and median center (MdC) spatial statistical tools. Both the CF and MdC results suggest that transfer stations in 2020 were located significantly closer to communities, and an improved level of landfill regionalization is observed. Smoother Landfill and Transfer Station radial curves are generally observed using the MdC tool. About 47.1% of the divisions are classified as challenging areas using the CF method, whereas only 41.1% of the divisions are classified as challenging areas using the MdC method. Six divisions (35.3%) are considered as appropriately managed by both CF and MdC methods. On the contrary, 23.5% of all divisions are suggested by both methods as challenging areas. Most divisions with an improving placement of waste facilities were located near the Canada-US border. The presences of major cities and total division population appear not key factors affecting the evolution of waste facility siting.The research reported in this paper was supported by a grant from the Natural Sciences and Engineering Research Council of Canada (RGPIN-2019-06154) to the corresponding author, using computing equipment funded by FEROF at the University of Regin
An evaluation on electronic waste management and product stewardship programs in North America
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Environmental Systems Engineering, University of Regina. x, 63 p.Electronic waste (E-waste) has been extensively investigated by researchers throughout the
globe, however specific research trends in North America (NA) are yet unknown. The first part
of the study attempts to present an up-to-date bibliometric view of e-waste studies and to
identify the research sub-fields and networks. A total of 271 documents were retrieved from the
Web of Science (WoS) database (from 2001 to 2022). E-waste research topic that originated
from NA, as well as its relative growth rate, collaborative measures, institutional productivity,
and the popular journals were evaluated in this bibliometric analysis. The first part of the study
showed that research productivity increased noticeably in the last decade. The USA has the
most e-waste publications (74.62%), followed by Canada (22.38%) and Mexico (10.44%). The
topic with the highest percentage of papers (151, or 55.72%) was environmental science.
Resources Conservation and Recycling was the most active journal on e-waste research. The
University of California, USA (10.70 %) played an active role in the publication, and
Ogunseitan, O. A. was the most productive author (4.80 %) in this field. Author’s keywords can
be generally grouped into four clusters. Network analysis results suggest that collaborative
activities by leading universities will likely boost the number of studies. Researchers and
policymakers will benefit from the first part of the study by gaining a better understanding of
the development and the content trends of e-waste research.
It is found in Part 1 that e-waste stewardship studies in Canada are limited, and they are
specifically addressed in part 2. The amount of e-waste generated worldwide is growing at an
explosive rate. The precious materials contained in this waste stream offers an ample business
opportunity that produces high returns for the recyclers both in informal as well as formal
sectors. A range of e-waste recycling companies have proliferated not only in developing
countries but also in industrialized nations. The second part of the study further analyzed and
evaluated e-waste management performances and recycling practices of a Canadian company
that operates throughout the country. The company’s annual performance report from 2012 to
2020 served as the source for the e-waste statistics and related materials for the second part of
the study. The corporate website is also considered in addition, to gain an overall understanding
of the business portfolio. Temporal variations of performance factors were examined, and
regression analysis was carried out to assess the relationships among various elements related
to the recycling features. The study findings show that the overall e-waste collection rate
throughout the country plummeted dramatically during the course of the investigation starting
from 1.1-5.04 kg/capita to 1.4-3.0 kg/capita. E-waste drop-off points designated by the company
have expanded by more than 800% and industry participation rose to more than 120% during
the study period. Furthermore, study reveals that around 77% people in Canada are aware of the
e-waste management and 97% people remain very close to the authorized e-waste collection
points. The outcomes disclose that there is no overall correlation between public awareness and
the rate of stewardship registration or e-waste collection. With just a few minor variations, the
company's sector-specific yearly spending allocation over the investigation period was nearly
identical. Corporation’s average total recycling expense ranges from 1,578
in 2020. The outcomes of the current study can potentially inform recycling entrepreneurs and
policy makers crafting methodical and strategic plans for the adoption of e-waste formalization
management systems.Studentye
Fusions of association schemes
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Mathematics, University of Regina. viii, 109 p.Since their introduction as symmetric coherent configurations by Bose and Mesner in 1959, association schemes have gained significant importance in algebraic combinatorics. An important breakthrough was achieved by Delsarte’s PhD thesis where he proved that many problems from coding theory, combinatorial design theory and statistics can be treated using the concept of association schemes [12]. Since its initial introduction, many algebraists and graph theorists have been studying the existence, construction and generalizations of various association schemes [1, 3, 7, 8, 17, 19, 28, 29, 30].
Because of their impressive construction, association schemes are useful to these subjects and there is always a search for new association schemes. One easy way to construct a new association scheme is by taking either direct or wreath products of two existing association schemes. One such example that we studied was given by Sankey in [32]. Another way to construct a new association scheme is by fusing specific relations of an existing association scheme. The resulting association scheme is known as a fusion (previously referred to as “subscheme” by mathematicians) [4].
The focus of this thesis is to examine a few important association schemes and classify them based on their fusions. It can be observed from literature that the nonexistence of nontrivial fusions is a rare phenomenon and this is the motivation behind this thesis. An association scheme, A, is said to be fusion-primitive if there does not exist any nontrivial fusions of A. In 1992, Muzychuk proved that there does not exist any nontrivial fusions of the Johnson scheme, J (n, k) for all n > 3k + 4 with k ≥ 4 [29]. In 1994, this result was further refined for all n > 3k + 1 by Uchida in [36]. In this thesis, we prove that the Johnson scheme does not have any nontrivial fusions for all n, n > 2k + 1 with k ≤ 20. In addition, we classify almost all of the multiplicity-free subgroups of the symmetric group based on their nontrivial fusions.
The Hamming scheme, H(n, q) is an important example in coding theory [10]. The fusionprimitivity of the Hamming scheme has been discussed before (see [28]). In this thesis, we study the generalized Hamming scheme, H(n,A) and prove that it is fusion-imprimitive (that is, it always has a nontrivial fusion). We also classify all fusions of the generalized Hamming scheme, H(2,A) where A is the association scheme corresponding to a strongly-regular graph.Studentye