identifier: Suryawanshi, Abhishek Rameshwar <https://research.library.mun.ca/view/creator_az/Suryawanshi=3AAbhishek_Rameshwar=3A=3A.html>   (2021) Commercial Pt/C nanoparticle catalyst enhancement by ionic liquid (IL)/organic ionic plastic crystal (OIPC) modification for oxidation of biofuels in fuel cells.  Masters thesis, Memorial University of Newfoundland.

abstract:
Due to rising environmental concerns, carbon neutral or carbon negative strategies are being
sought along with a wide range of clean energy conversion technologies, such as fuel cells. Fuel
cells are being investigated owing to their low emissions, high theoretical efficiency, and
simplicity of operation. A significant barrier to fuel cell commercialization is cost, mainly due to
the use of expensive noble metals as catalysts, e.g., Pt. One strategy would still rely on Pt as a
catalyst material but with electrocatalytic enhancement by OIPC (organic ionic plastic crystal) or
IL (ionic liquid) modification which lowers the amount of Pt needed. IL are large organic salts
with melting points below 100 °C, while OIPC are chemically similar; however, they have higher
melting points with several solid-solid phase transitions below the melt which give rise to their
plasticity. Solid catalyst with an ionic liquid layer (SCILL) is the concept of catalyst modification
with a thin IL layer and has been demonstrated as a facile approach to improve catalyst activity.
IL/OIPC modified 20% mass Pt/C nanoparticles were investigated as an anodic catalyst for proton
exchange membrane fuel cells through oxidation of different biofuels such as methanol and formic
acid (FA). Herein, three different tetraalkylphosphonium cations were paired with the
bis(trifluoromethylsulfonyl)imide (NTf2) anion. Three n-butyl group were employed, while the
fourth arm bound to the phosphonium core was varied in length from 4 to 8 carbons. Each gave
excellent hydrophobicity as well as thermal and electrochemical stability. Tetrabutylphosphonium
bis(trifluoromethylsulfonyl) imide (P4444NTf2) possesses a melting point of 85 °C and a single
solid-solid phase transition was observed below this temperature, making it an OIPC, while the
other salts were liquids at room temperature. As evidenced through voltammetric analysis,
commercial 20% Pt/C catalysts demonstrated enhanced organic fuel oxidation when modified by
either IL or OIPC of up to 2.5×. These results are highly significant and mean a reduction in the
III
amount of Pt needed – an enormous cost savings. IL/OIPC physicochemical characterization will
also be discussed.


identifier: Slaney, Jonathan <https://research.library.mun.ca/view/creator_az/Slaney=3AJonathan=3A=3A.html>   (2021) Examining the association between cycling infrastructure exposure and physical activity: a natural experiment study in Victoria, Canada.  Masters thesis, Memorial University of Newfoundland.

type: Thesis NonPeerReviewed

abstract:
Background: Most Canadians are not meeting physical activity guidelines. Physical inactivity is
an epidemic related to alarming rates of preventable disease and economic burden. Health
benefits ensue from modest increases in physical activity (i.e., 5 minutes daily). Despite the
health benefits, there is limited evidence about interventions to increase physical activity at the
population level. Built environment interventions, like bicycle infrastructure, are one
understudied intervention with the potential to increase total population physical activity. The
purpose of this study was to examine the physical activity impacts of bicycle infrastructure.
Intervention: The intervention studied is the All Ages and Abilities (AAA) Cycling Network in
Victoria, BC. This network of bicycle infrastructure is a $7.75M commitment. In 2018, a 5.4km
grid of protected cycle tracks was built downtown.
Research Design: Adults were recruited in Victoria who ride bicycles at least monthly. Baseline
activity data were recorded in 2017 (n = 281) using surveys, Global Positioning System (GPS),
and accelerometer data, with a follow-up data collection in 2019 (n = 315). The primary outcome
was moderate to vigorous physical activity (MVPA), assessed via accelerometer data.
Hypothesis: Exposure to new active transportation infrastructure will be associated with
increased MVPA over time.
Analysis: I calculated exposure measures to the AAA Cycling Network using GPS and
Geographic Information System using intersections. I used regression models to examine the
associations between exposure to new infrastructure and total location-based physical activity
levels, controlling for confounders.
Results: In the multilevel models analyzing the interaction between exposure and wave with
covariates, wave two, compared to wave one, saw a non-statistically significant increase in
MVPA of 0.93 minutes per week [CI = -5.28, 7.14]. Comparing the models with and without
covariates suggests that the wave one and wave two comparisons were highly confounded by
individual and weather covariates.


identifier: Hossen, Mohammed Khalid <https://research.library.mun.ca/view/creator_az/Hossen=3AMohammed_Khalid=3A=3A.html>   (2021) A numerical study of the subgrid-scale fluid motion in turbulent flows.  Masters thesis, Memorial University of Newfoundland.

abstract:
The numerical solution of the Navier–Stokes equations for different turbulence regimes has become
more prevalent for many years. This thesis has investigated the large eddy simulation method for solving
the Navier–Stokes equations. A primary goal is to design a subgrid-scale model for small-scale
coherent vortices while statistically maintaining an accurate dissipation rate. Past investigations of
turbulence indicate that the vortex stretching mechanism can transport the turbulence kinetic energy
from large to small scales. Thus, a turbulence model can learn the energy dissipation rate from the
statistics of the velocity gradient tensor. Following such a hypothesis, this thesis validates how vortex
stretching can directly account for the subgrid-scale dissipation rate while solving the Navier–Stokes
equations on a relatively coarse mesh. Current findings suggest a potential subgrid-scale model based
on invariants of the square of the velocity gradient tensor. The turbulence statistics obtained from the
proposed model agree well with the three commonly used dynamically adaptive large eddy simulation
techniques. The results also suggest that statistics of the velocity gradient tensor dynamically
adapt the dissipation rate to the local variation of turbulence. Furthermore, considering the square of
the deformation tensor, this thesis suggests that the singular values of the snapshots of the velocity
gradient may improve the model in future studies of more challenging turbulent flows.


identifier: Andrews, Samantha <https://research.library.mun.ca/view/creator_az/Andrews=3ASamantha=3A=3A.html>   (2021) Moving targets: safeguarding migratory pelagic species in a changing ocean.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Migratory and other highly mobile species, which rely on multiple, often spatially discrete and heterogeneous environments throughout their life cycles, play critical roles in the functioning and dynamics of communities and ecosystems. However, migratory species face multiple anthropogenically driven threats to their survival as they move between and use different areas. Understanding migratory species distributions and drivers of those distributions is essential to develop effective strategies that reduce or remove anthropogenic threats to their wellbeing and persistence. Yet, the spatial-temporal dynamism of migratory species movements and distributions, particularly under changing conditions, presents additional challenges for researchers and managers. Here, I use distribution modelling and quantitative analysis tools to examine the changing distributions of suitable habitat for marine pelagic species over horizontal (longitude and latitude) and vertical (depth) space, time and between ocean climates, and deconstruct how modelled distributions of prey can inform the design and management of area-based management tools for migratory seabird predators. First, I applied a species distribution model (Maxent) to explore the average monthly spatial-temporal dynamics of suitable habitat of the migratory pelagic forage fish capelin (Mallotus villosus) in Atlantic Canadian waters. I found that the distribution of habitat suitability varied across horizontal and vertical axes and among monthly models. Furthermore, I found that the importance of modelled covariates such as temperature varied between models. Next, I used a series of spatial and temporal analyses to examine how shifts in the North Atlantic Oscillation influenced the availability of suitable habitat over horizontal and vertical axes between 1998 and 2014. I found substantial stability in the location of predicted suitable capelin habitat between positive and negative phases. However, in six of the ten months modelled, predicted habitat suitability scores showed a declining trend over time. Finally, I present a framework for explicitly integrating changing prey availability into adaptive area-based management for
seabirds throughout their migratory cycle. This framework focuses on using existing modelling, forecasting, and analysis tools to identify potential seabird foraging spaces, and allows for the input of new knowledge and data to provide managers with the best available information for iterative and adaptive decision-making.


identifier: MacDonald Muth, Sara Mime <https://research.library.mun.ca/view/creator_az/MacDonald_Muth=3ASara_Mime=3A=3A.html>   (2021) Marginally outer trapped (open) surfaces in 4+1 dimensional spacetimes.  Masters thesis, Memorial University of Newfoundland.

abstract:
In binary black hole mergers and other highly dynamical spacetimes, the surface of
most obvious interest, the event horizon, is often computationally difficult to locate.
Instead, it is useful to use quasi-local characterizations of black hole boundaries, such
as Marginally Outer Trapped Surfaces (MOTS), the outer-most of which is (often)
the apparent horizon. Recent studies have shown that MOTS not only characterize
boundaries, but may also be found in black hole interiors. This has been seen in 4D
Schwarzschild and Reissner-Nordstrom, as well as in binary black hole mergers.
In this thesis, behaviours of MOTS|and their open generalization, Marginally
Outer Trapped Open Surfaces (MOTOS)|in the interior of five-dimensional black
holes are studied; both static (Schwarzschild), and rotating (Myers-Perry). Similar to
four-dimensions, we find infinitely many self-intersecting MOTS in 5D Schwarzschild.
We find finitely many self-intersecting MOTS in Myers-Perry, finding fewer as the
rotation increases. However, we do find oscillations of the MOTOS, which is novel
behaviour.


identifier: Jyothini, Abinu Ajithan <https://research.library.mun.ca/view/creator_az/Jyothini=3AAbinu_Ajithan=3A=3A.html>   (2021) Experimental and computational studies of the effect of lung surfactant protein-B fragment, SP-B₁₋₉, on m lipid bilayers.  Masters thesis, Memorial University of Newfoundland.

abstract:
The effect of lung surfactant protein fragment, SP-B₁₋₉, on a model lipid bilayer was
investigated. Lung surfactants are lipid-protein complex mixtures that help in reducing the
effort needed for breathing by lowering the surface tension that builds up at the alveolar
air-liquid interface.
Recent research using deuterium NMR to examine the impact of SP-B fragments on
bilayer model membranes found that the SP-B fragment, SP-B(1-25, 63-78), had a greater
effect on the lipid chain acyl chain orientational order than the fragment, SP-B (8-25, 63-
78). Both of these SP-B fragments include the first and last helices of SP-B, however they
vary in the presence or absence of the insertion motif SP-B₁₋₇. This indicates that the
insertion motif may contribute to the ability of SP-B to promote the bilayer reorganisation
required for lung surfactant function. To gain a better understanding of the insertion motif’s
interaction with surfactant lipids, we used deuterium NMR and GROMACS molecular
dynamic simulations to examine the effect of SP-B₁₋₉, on the acyl chain order of a lipid
bilayer comprised of the lipids DPPC and POPG in a 7:3 ratio.
2H NMR studies with DPPC-d62/POPG (7:3) and SP-B₁₋₉ at peptide-to-lipid ratios of
0.066 and 0.098 revealed no detectable effects in the first moment and order parameter profiles.
Even after freezing and thawing the samples, no significant impact of the peptide was
detected. On the other hand, MDsimulations of lipid bilayers containing DPPC/POPG(7:3)
and SP-B₁₋₉ at a peptide-to-lipid ratio of 0.031 showed a reduction in the acyl chain orientational
order of the lipid chain. This difference between the simulation results and the
experiments could be due to the aggregation of the peptides in the experiments. MD simulations
also reveal the peptide’s average orientation and conformation in the lipid bilayer. It
was found that the residues at peptide positions 5, 6, and 7 (Leucine, Proline, and Tyrosine,
respectively) had the potential to be part of a helical segment with an average helicity of approximately
45%. The peptide seems to slope into the bilayer, with the last few residues at
the N-terminal end remaining horizontal to the bilayer plain, not going closer to the bilayer
centre.


identifier: Wiest, Adam <https://research.library.mun.ca/view/creator_az/Wiest=3AAdam=3A=3A.html>   (2021) Stratigraphy and detrital zircon U-Pb-Hf isotope provenance of the Faro Peak formation, Central Yukon: implications for the Early Jurassic evolution of the Northern Canadian Cordillera.  Masters thesis, Memorial University of Newfoundland.

abstract:
Late Triassic to Early Jurassic plate convergence and crustal thickening along the Cordilleran
margin led to exhumation of the Intermontane terranes and subsequent deposition of multiple syntectonic
stratigraphic assemblages in northwestern Canada. The Faro Peak formation is exposed
in central Yukon along the Vangorda fault, the local suture between the Yukon-Tanana and Slide
Mountain terranes, and constrains the timing and spatial extent of Early Jurassic tectonic
exhumation. The Faro Peak formation unconformably overlies Yukon-Tanana terrane basement
rocks (Snowcap assemblage) and unnamed Triassic strata (formerly lower member of the Faro
Peak formation) and consists of Sinemurian to Toarcian massive sandstone and pebble to boulder
conglomerate units. Field stratigraphic and detrital zircon U-Pb-Hf isotope studies indicate that the
Faro Peak formation was locally sourced from Late Triassic to Early Jurassic arc- to syn-collisional
intrusive rocks and mid- to upper Paleozoic arc and marine sedimentary successions. Snowcap
assemblage rocks were recycled into the overlying Faro Peak formation and mostly consist of
quartz-mica schist and quartzite units with Cryogenian and older maximum depositional ages and
Precambrian detrital zircon grains that indicate northwestern Laurentian provenance. The Faro
Peak formation was deposited in an isolated, structural basin by sediment gravity flows along the
proto-Vangorda fault and separated from coeval, syn-tectonic deposition in the Whitehorse trough
of southern Yukon by a regional drainage divide.


identifier: Elzaidi, Abdulrazak H. <https://research.library.mun.ca/view/creator_az/Elzaidi=3AAbdulrazak_H=2E=3A=3A.html>   (2021) Marine icing sensor array for measuring ice thickness.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Marine Icing is the process of ice accumulation on ships and other offshore structures in cold
regions that can create serious working conditions besides the adverse effects to the offshore operations
efficiency. Monitoring of icing conditions together with a number of de-icing strategies is
therefore important in decreasing the safety hazards and increase the working effectiveness. Detection
of the ice accretion rate on the offshore structures is a challenge due to the harsh environment
and the multiphase property of the ice.
This thesis is focused on developing a low cost array sensor for the ice accretion detection applicable
to the harsh marine environments. We utilized a stray-capacitance technique that encodes a
layered multiphase icing accretion uniquely. Capacitive sensors are popular in diverse industrial settings
due to their relative simplicity, robustness and low cost. The sensor transducers are compatible
with the printed circuit board technology which made this research time effective.
The thesis is based on three distinct publications, two journal papers (IEEE, MDPI) and one
peer-reviewed conference paper (IEEE), each in a separate chapter. All publications include a theoretical
background, simulations, and experimental validation. The underlying novel approach that
is more or less shared in all applications is the use of linearly independent sensor array for unique
multiphase ice detection. The first two papers utilize a different inter-electrode spacing array but a
different signal conditioning algorithm. The third paper then uses an array of constant spacing but
different dielectric layer height.
As stated above, the main objective of this work is to measure the multiphase icing accretion
which consists of water above ice, the real situation which has not been addressed to date. A
number of different techniques have been developed over the last two decades mainly as a response
to the rapidly expanding offshore oil&gas in northern regions, offshore wind power generation, or
shipping across or fishing in arctic waters. This thesis outlines three methods that can be directly
applied to these industries.


identifier: Salami, Adeniyi <https://research.library.mun.ca/view/creator_az/Salami=3AAdeniyi=3A=3A.html>   (2022) A numerical investigation on the axial pullout tests of buried pipes.  Masters thesis, Memorial University of Newfoundland.

abstract: Pipelines may unavoidably be routed through areas susceptible to ground movement. The reliability of pipelines comes into question during events of ground movements due to generated loads due to ground movements. It is therefore imperative to accurately predict the loads generated to enable the proper design of pipelines. Many researchers have produced high-quality data from tests that idealize real-life conditions by pulling pipe through fixed soil, although in the actual event of ground movement, unstable soil moves away from stable soil that fixes the pipe. This study develops a finite element modeling technique to simulate laboratory conditions by pulling pipe through fixed soil, and the real-life condition is simulated by pulling soil while pipe is fixed in place. The finite element technique is also used to investigate the effect of pipe length, diameter, burial depth, and internal pressure for both steel and polyethylene pipes. The study reveals that short steel pipelines beginning from 1 m length developed a higher peak pull-out force for pipe pulling simulation compared to soil pulling simulation, this behaviour changes for longer steel pipelines from 6.5 m where soil pulling simulation predicts a higher peak pull-out force compared to pipe pulling simulation. Polyethylene pipelines simulated for pipe pulling predict higher peak pull-out forces of varying percentages with increase in length when compared to soil pulling. The effect of increase in soil width is not significant in the prediction of pull-out forces for both simulations. An increase in diameter and burial depth also increases pull-out forces for both simulations. Increase in pressure is not significant in the development of pull-out forces for steel pipelines while in polyethylene pipelines an increase in pressure increases development of pull-out forces.


identifier: Javed, Bilal <https://research.library.mun.ca/view/creator_az/Javed=3ABilal=3A=3A.html>   (2021) Wood ash and paper sludge: potential liming and nutrient source for crop production in podzolic soils.  Masters thesis, Memorial University of Newfoundland.

abstract: The Corner Brook Pulp and Paper Ltd (CBPPL) produces approximately 10,000 Mg of wood ash (WA) and 47,500 Mg of paper sludge (SL), annually, as waste byproducts. Among these wastes WA is landfilled as part of the disposal management program administered by the company whereas SL is burnt to generate steam for paper mill operations. This practice is not ideal due to high disposal costs and environmental concerns. In addition, WA and SL contains essential nutrients such as Ca, K and Mg that favors plant growth and could increase soil pH due to its calcium carbonate equivalent ability. One sustainable management practice is the land application of WA and SL to agricultural soil, increasing soil pH and enhancing crop growth and yield. Herein, we conducted greenhouse studies to evaluate the effect of WA and SL alone and in combination with biochar (BC) on growth, yield, nitrogen dynamics, and heavy metals mobility in the soil-plant system of annual ryegrass (Lolium perenne L.) and kale (Brassica oleracea L.). In study 1 soil with pH 5.7 and 2.7 % organic matter was used and in study 2, soil pH and organic matter were 5.2 and 4.5 % respectively. Results of the study 1 and 2 indicated that WA was effective in achieving the target soil pH of 6.3 and produced 71% and 42% more biomass than control in annual ryegrass, respectively. Similarly, WA application showed 28% and 27% higher yield than control in kale in both studies, respectively. BC addition significantly decreased 15 – 20 % Pb and Cd uptake in annual ryegrass and kale crops in both studies. Study results suggest that WA could be used as a liming and nutrient source and could be a substitute for limestone used in improving soil pH in agriculture production system. Furthermore, BC amendment with WA or SL could be a promising strategy in decreasing heavy metals uptake in agronomic and horticultural crops.


identifier: Wells, Brenda N <https://research.library.mun.ca/view/creator_az/Wells=3ABrenda_N=3A=3A.html>   (2022) Influence of local PO₂ on skeletal muscle microvascular blood flow during hyperinsulinemia.  Masters thesis, Memorial University of Newfoundland.

abstract:
The goal of this thesis was to test the hypothesis that insulin mediated hyperemia is partially dependent on local muscle oxygen concentration. To do so, microvascular blood flow was measured in response to varying imposed concentrations of oxygen in rat skeletal muscle. Sprague-Dawley rats were anesthetized, and the extensor digitorum longus (EDL) was reflected onto an inverted microscope. Intravital video microscopy sequences were recorded during baseline and hyperinsulinemic euglycemia. The muscle was reflected over a glass stage insert (Experiment 1a and 1b), or over a gas exchange chamber (Experiment 2), and microvascular capillary blood flow was recorded during sequential changes (7%-12%-2%-7%) of oxygen (O₂) concentration. Blood flow was measured by the red blood cell supply rate (SR) in number of cells per second. In Experiment 1a, supply rate (SR) increased from 8.0 to 14 cells/s at baseline to euglycemia (p = 0.01), while no significant SR variation was detected after performing a sham hyperinsulinemic euglycemic clamp (Experiment 1b). In Experiment 2, SR decreased at 12% O₂ and increased at 2% O₂, compared to 7% O₂, under both experimental conditions. SR responses to oxygen square wave oscillations during euglycemia were not different to those at baseline at each O₂ concentration (p > 0.9). Our results suggest the increase in blood flow observed in response to insulin is eliminated if tissue oxygen microenvironment is clamped at given oxygen concentrations.
All animal protocols were approved by Memorial University’s Institutional Animal Care Committee.


identifier: O'Reilly, Meghan <https://research.library.mun.ca/view/creator_az/O=27Reilly=3AMeghan=3A=3A.html>   (2021) Ethnicity and the 2019 Canadian federal election: do racialized candidates increase voter turnout?  Masters thesis, Memorial University of Newfoundland.

abstract:
Voting behaviour research in Canada has shown that racialized voters tend to support racialized candidates and candidates with whom they share an ethnic identity. However this work doesn’t address why racialized
voters might be turning out to vote in the first place. Using data from the 2019 Canadian Election Study, this
project helps to bridge tha gap by examining the mobilizing effect that racialized candidates may have had
on racialized voter turnout during the 2015 and 2019 Canadian federal elections. South Asian candidates
were found to positively increase reported turnout of South Asian voters in 2015. Similarly, the presence of a Chinese candidate in 2015 led to increased reported turnout among Chinese voters and increased reported
plans to vote in 2019. These findings suggest that the presence of racialized candidates was linked to
increased turnout and plans to vote among voters with the same ethnic identity. The analysis in this thesis
provides further insight into the dynamics of racialized participation in Canadian politics.


identifier: Fardy, Sean <https://research.library.mun.ca/view/creator_az/Fardy=3ASean=3A=3A.html>   (2021) Positive mental health of individuals with a cancer diagnosis: exploring the role of physical activity.  Masters thesis, Memorial University of Newfoundland.

abstract:
A cancer diagnosis is a significant life event that can lead to psychological distress and leaves individuals diagnosed with cancer at a higher risk of mental illness. Mental illness, such as depression and anxiety, is common in cancer patients and is associated with increased hospital stay time and treatment efficiency. Therefore, it is essential to prioritize the mental health of cancer patients. It is now recognized that mental health is not merely the absence or presence of mental illness; instead, it is a syndrome of symptoms of an individual’s subjective well-being. This is where positive mental health has been introduced. Positive mental health is a concept recognized by the World Health Organization that views mental health as an evaluation of one’s subjective well-being and how well they see themselves functioning in life, regardless of the absence or presence of mental illness. Therefore, our focus should turn to the promotion and protection of the positive mental health of cancer patients. Focusing on the promotion and protection of positive mental health will decrease the risk of these individuals developing mental illness over time which will, in turn, protect against increased hospital stay time and treatment efficiency. Highlighted here is the importance of exploring different avenues for promoting and protecting the positive mental health of individuals diagnosed with cancer. Previous studies have indicated that physical activity has psychological benefits as it can improve and prevent symptoms of anxiety and depression in cancer patients. Therefore, physical activity could play a role in promoting and protecting the positive mental health of cancer patients. This study examined how physical activity is associated with positive mental health among individuals, ages 20-80+, diagnosed with cancer. Compared to those without a diagnosis of cancer, those with a diagnosis had significantly lower scores on measures of positive mental health. However, among the individuals who reported a cancer diagnosis, the average number of hours of
moderate or vigorous activity in the past week was a significant predictor of positive mental health. The implications of these findings are discussed in this study.


identifier: Rizutto, Matteo <https://research.library.mun.ca/view/creator_az/Rizutto=3AMatteo=3A=3A.html>   (2021) From elements to landscapes: the role of terrestrial consumers in ecosystem functioning.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Consumers are key actors in ecosystems, shaping processes and functions at multiple spatiotemporal
scales via their interactions with biotic and abiotic ecosystem features. Yet, research
on the dynamics of local and meta-ecosystems rarely accounts for the effects of consumers—
particularly terrestrial mammals. Two hurdles hamper progress in this field: the lack of common
units of measurement for biotic and abiotic ecosystem components, and the need for flexible,
system-agnostic ways to investigate how consumers interact with and influence ecosystem
functioning. In this dissertation, I offer a concerted approach to address these issues, integrating
wildlife, landscape, and ecosystem ecology within an ecological stoichiometry framework. I
begin by showing that terrestrial mammals are variable in their ecological stoichiometry, using
data from the snowshoe hare (Lepus americanus), a keystone boreal herbivore. Importantly, unlike
invertebrates, organismal stoichiometry in vertebrates appears unrelated to age, sex, body
size, and body condition. Building on these results, I investigate the responses of terrestrial herbivores
to biotic variability in their environment, finding that snowshoe hares vary their space
use when facing intraspecific variability in the stoichiometry of their foraging resources. Hares
had larger home ranges in areas of poor or highly variable forage stoichiometry compared to areas
of high and consistent forage stoichiometry. This differential space use by consumers may
elicit changes in both their ecology and ecosystem dynamics. Thus, I develop a novel mathematical
model of a meta-ecosystem to investigate how multiple types of consumer movement
over the landscape influence ecosystem processes and functions. Expanding a classic, two-patch
meta-ecosystem model to include the surrounding matrix, I demonstrate that active, non-diffusive
movement of consumers can reduce or enhance ecosystem functions at local and regional spatial
scales. Throughout my thesis, ecological stoichiometry ties together the diverse themes of each
chapter, further demonstrating how elemental currencies can work as shared units of measurement
across levels of biological organization. Overall, my thesis combines a laboratory study,
spatial statistical models fit to a field-based case study, and a novel mathematical model to provide
testable predictions to guide future research into the role of consumers within meta-ecology.


identifier: Sran, Ashmean Kaur <https://research.library.mun.ca/view/creator_az/Sran=3AAshmean_Kaur=3A=3A.html>   (2021) Design requirements for an online data exchange platform to bridge the gap between farmers and researchers in India.  Masters thesis, Memorial University of Newfoundland.

abstract:
The rising awareness of information transparency and the increasing trend of citizen participation in the agriculture sector has created new opportunities for information sharing. There are numerous information resources available for farmers from private, government sources and industry stakeholders. There are also various farm surveys by which farmers contribute towards the agricultural sector. However, no such platform connects farmers and researchers in which data exchange happens simultaneously between them. This gap in information exchange contributes to slow growth in the advancement of the agricultural sector. Research results do not reach the end-users in time to adopt agricultural improvement practices. Often researchers do not get the opportunity to engage and encourage farmers to be citizen scientists to contribute to the research.
In this thesis, we develop design requirements for an online web-based prototype data exchange platform to bridge the gap between researchers and farmers. The platform can serve as a way to build farmers’ trust in researchers and encourage them to contribute more towards agricultural research to develop the sector. We believe that the findings of this study will prove helpful to interface designers and researchers to inform and guide future work in this critical area.


identifier: Mamudu, Abbas <https://research.library.mun.ca/view/creator_az/Mamudu=3AAbbas=3A=3A.html>   (2022) Dynamic risk-based analysis of petroleum reservoir production systems.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Petroleum reservoirs are complex process systems defined by intrinsically uncertain data and a distinct pressure gradient. The upstream sector’s assets are with huge uncertainties and high risks. Thus, the investments in these complex geologic process systems majorly suffer severe dynamic risks due to the process’ complex dynamics, process data’s temporal and spatial variabilities, and data/model’s uncertainties. Over time, the complex dynamic risks of the reservoir production system have resulted in unforeseen severe production fluctuations, total process system failures, and/or abrupt well shut-in due to uncontrollable circumstances. Hence, the need to introduce a multipurpose dynamic risk-based smart production prognostic approach to address the outlined inherent petroleum production challenges. This thesis presents dynamic risks assessment models for dynamic risks-based analysis of petroleum reservoir production systems. Different possible production scenarios are captured with the developed adaptive hybrid model with the following highlighted novel scientific contributions. Firstly, a dynamic risk-based predictive model is introduced to forecast production and capture the parameters variabilities, data and model’s uncertainties, and dynamic risks of primary recovery processes. This is followed with an introduced novel model for dynamic risks monitoring and production forecast of secondary recovery processes. A novel model is also presented to incorporate dual reservoir energy support mechanisms in production predictions and associated dynamic risks forecast under lift mechanisms. In addition, a dynamic economic risks analysis model is proposed to consider economic risk assessment of the reservoir production systems. Lastly, a dynamic risks-based smart model is proposed to capture sand face pressure enhancement influence on the reservoir production system with production pump schemes.


identifier: Sadri, Behzad <https://research.library.mun.ca/view/creator_az/Sadri=3ABehzad=3A=3A.html>   (2021) Photonic microstructures in optical fiber and their sensing applications.  Masters thesis, Memorial University of Newfoundland.

abstract:
Optical fiber sensors have attracted significant interest in their physical properties and potential applications due to their advantages of compact size, light weight, immunity to electromagnetic interference, and viability in harsh environments. To achieve the potential for applications, it is essential to reveal the underlying physics through both experimentation and simulation, which is an ongoing task now. In this study, microstructures in optical fiber, such as tapers and long-period grating (LPG), are investigated by simulation with COMSOL Multiphysics software, which is also compared with experiments in this study or the experimental results achieved by this group. In the experimentation of this study, the effects of different fabrication parameters on the formation of micro-taper in optical fiber and the transmission spectra of the resulting LPGs are carried out, which indicates that the average diameter of the micro-taper decreases and a blueshift in the transmission spectrum of the LPG occurs by increasing any of the three fabrication parameters such as arc current, arc duration, and tension along the fiber. The sensitivities of LPG to environmental refractive index and temperature are studied computationally, which shows the highest sensitivity of refractive index of 171.82 nm/RIU (Refractive Index Unit) and the temperature sensitivity of 10 pm/℃. Furthermore, tapered fibers in the configurations of either single or in-line Mach-Zehnder interferometer are studied as biosensors for detecting the concentration of Streptavidin (SV) protein computationally and compared with the experimental results previously obtained in our research group. The simulation results show good agreement with the experimental results
indicating the effective refractive indices of the coating materials play a significant role in determining the sensitivity. The findings achieved from this study are helpful for designing LPG-based and tapered fiber-based optical fiber sensors and biosensors, which enable the applications of these optical sensors in various fields, such as telecommunication, chemistry, medical and environmental sciences.


identifier: Elkurtehi, Ali I. <https://research.library.mun.ca/view/creator_az/Elkurtehi=3AAli_I=2E=3A=3A.html>   (2017) Synthesis and characterization of transition metal amino-phenolate complexes and their reactivity towards the oxidation of lignin model compounds and cyclic carbonate formation.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Vanadium and manganese complexes supported by amino-bis(phenolate) ligands, were
synthesized and characterized. The catalytic activity of the vanadium complexes in the
aerobic oxidation of 4-methoxybenzyl alcohol and 1,2-diphenyl-2-methoxyethanol was
explored. Whereas, the complexes showed limited reactivity in H₂O₂-mediated oxidation
of diphenylether and benzylphenylether. The manganese complexes showed low activity
for the aerobic oxidation of 4-methyoxybenzylalcohol and 1,2-diphenyl-2-
methoxyethanol.
The catalytic synthesis of cyclic carbonates under solvent free conditions using vanadium
and manganese complexes, epoxides and carbon dioxide was attempted and monitored by
in situ IR and NMR spectroscopic techniques. Variable temperature kinetic studies were
performed and the activation energies for cyclic carbonate formation were determined
experimentally using this situ IR spectroscopic data. The catalysts showed excellent
activity and good stability in these reactions.


identifier: Johns-Buss, Emily <https://research.library.mun.ca/view/creator_az/Johns-Buss=3AEmily=3A=3A.html>   (2021) Detrital zircon fission-track thermochronology and U-Pb geochronology of syn-rift, Lower Cretaceous Hibernia Formation strata, Jeanne d’Arc basin, offshore Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract:
The Newfoundland margin was established after Mesozoic continental rifting broke up
supercontinent Pangea and opened the North Atlantic Ocean between North America and Europe.
Normal faults cut through the lithosphere to accommodate extension and created a dynamic
landscape that shifted as the rift system evolved over ~150 million years. Upper Triassic to Upper
Cretaceous sedimentary rock units of the Jeanne d’Arc basin, Grand Banks, offshore
Newfoundland, have been broadly correlated to rift processes, however, the precise timing of riftrelated
exhumation and details of ancient drainage systems were uncertain. New stratigraphic and
sediment provenance results for Lower Cretaceous Hibernia Formation strata, including those that
are known reservoir units at the Hibernia oil field, confirm rift-related exhumation was occurring
in the Grand Banks during the Triassic to Jurassic and Early Cretaceous and can be tied to rift
processes occurring further offshore in deep-water settings. North-flowing, Early Cretaceous
rivers and delta systems drained highlands that were located south of the Jeanne d’Arc basin and
comprised both uplifted rocks of the Appalachian orogen and active, syn-rift volcanic centers.


identifier: Flight, Garrett <https://research.library.mun.ca/view/creator_az/Flight=3AGarrett=3A=3A.html>   (2021) Investigating the challenges that face refugee students in Newfoundland and Labrador - an educators' perspective.  Masters thesis, Memorial University of Newfoundland.

abstract:
Using a series of semi-structured interviews to gather data, educators were asked to
explore the struggles that refugee students face, explain how the current system is effective and
ineffectual, and make recommendations for good teaching practices with this at-risk
demographic. Extracted from twelve interviews from these educators, who all have experience
teaching refugee students, were obstacles that are identified by three classifications: academic,
social, and emotional. Hindrances and successes in the current refugee education model have
been identified from the perspective of educators. Lastly, the study makes recommendations to
improve the educational experience for all stakeholders and to create an environment where
refugee students can overcome the massive challenges that they encounter. The participants
teach and administrate from Grades 7-12 and have a vast range of experience. Results of the
study were robust and many themes came from the data. These include recommendations of
investing more resources (i.e. teacher allocation and training), building strong student-teacher
relationships at a school wide level, participating in trauma informed practice, and implementing
early intervention for students who arrive under the age of Grade 7.


identifier: Odan, Mohamed Abdalla <https://research.library.mun.ca/view/creator_az/Odan=3AMohamed_Abdalla=3A=3A.html>   (2021) Investigation of pressure and temperature gradient in four-phase flow in a complex horizontal pipeline.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
The oil and gas (O&G) industry uses multi-phase and multi-component pipeline flows to move product from one site to another or to different areas within the same site. In extreme environments, such as offshore or the Arctic, the development of four-phase flows in a complex pipeline can bring even more challenges to the project. Jumpers and bends need to be able to is to withstand pressure drops and hydrodynamic loads from internal multi-phase flows and the current, respectively.
The study outlines the development of an experiment to investigate of pressure and temperature gradients in four-phase flows in a complex pipeline. Due to the excessive temperatures and pressures of the oil transport pipeline system, the main pipes include shorter pipes (bends and jumpers) that are attached to the manifold at the pipeline. These shorter pipes are used to enable expandability and prevent system failure.
The present work examines the practicality of applying a system of four-phase, four-fluid flows for transporting a multi-phase flow (sand, water, gas, and oil) along a flow loop horizontal pipeline with many multiple bends and jumpers. This experimental set-up can be used for investigating a wide variety of multi-phase flow problems considered in the this research. As a means to precisely measure and predict the characteristics of thermo- and hydro-dynamic multi-component mixtures, models representing the multi-phase behavior and equilibrium phase are created and tested. Additionally, the study looks at heat transfer, mass, and momentum in both the flow and the pipeline walls, and offers equations to describe their interrelationships. Another focus of this research is to obtain a Computational Fluid Dynamics (CFD) investigation of multi-phase flow phenomena in order to characterize the impact of pressure gradients and flow regimes due to various types of phase flow techniques used in the petroleum industry and in horizontal pipelines.
The results of this thesis offer fundamental and practical guidance for the analysis and design of flow loop pipeline multi-phase flow systems and devices incorporating four-phase flows (sand, water, gas, and oil) through a flow loop pipeline. The novel results were obtained with carefully controlled flow loop pipeline and volume fractions, which show a significant impact on temperature and pressure drops. Dimensionless numbers in fluid mechanics and pressure drop results show good agreement with the experimental data.
Further, the experimental and modeling approach of this thesis makes a unique contribution to the O&G field and to the design of transport pipelines for processing four-phase flows that include bends and jumpers.


identifier: Khoshafa, Majid Hamoud Ahmed <https://research.library.mun.ca/view/creator_az/Khoshafa=3AMajid_Hamoud_Ahmed=3A=3A.html>   (2022) Physical layer security in 5G and beyond wireless networks enabling technologies.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Information security has always been a critical concern for wireless communications due
to the broadcast nature of the open wireless medium. Commonly, security relies on cryptographic
encryption techniques at higher layers to ensure information security. However,
traditional cryptographic methods may be inadequate or inappropriate due to novel improvements
in the computational power of devices and optimization approaches. Therefore,
supplementary techniques are required to secure the transmission data. Physical layer
security (PLS) can improve the security of wireless communications by exploiting the characteristics
of wireless channels. Therefore, we study the PLS performance in the fifth generation
(5G) and beyond wireless networks enabling technologies in this thesis. The thesis
consists of three main parts.
In the first part, the PLS design and analysis for Device-to-Device (D2D) communication
is carried out for several scenarios. More specifically, in this part, we study the
underlay relay-aided D2D communications to improve the PLS of the cellular network. We
propose a cooperative scheme, whereby the D2D pair, in return for being allowed to share
the spectrum band of the cellular network, serves as a friendly jammer using full-duplex
(FD) and half-duplex (HD) transmissions and relay selection to degrade the wiretapped
signal at an eavesdropper. This part aims to show that spectrum sharing is advantageous
for both D2D communications and cellular networks concerning reliability and robustness
for the former and PLS enhancement for the latter. Closed-form expressions for the D2D
outage probability, the secrecy outage probability (SOP), and the probability of non-zero
secrecy capacity (PNSC) are derived to assess the proposed cooperative system model. The
results show enhancing the robustness and reliability of D2D communication while simultaneously
improving the cellular network’s PLS by generating jamming signals towards the
eavesdropper. Furthermore, intensive Monte-Carlo simulations and numerical results are
provided to verify the efficiency of the proposed schemes and validate the derived expressions’
accuracy.
In the second part, we consider a secure underlay cognitive radio (CR) network in the
presence of a primary passive eavesdropper. Herein, a secondary multi-antenna full-duplex
destination node acts as a jammer to the primary eavesdropper to improve the PLS of the
primary network. In return for this favor, the energy-constrained secondary source gets
access to the primary network to transmit its information so long as the interference to the
latter is below a certain level. As revealed in our analysis and simulation, the reliability and
robustness of the CR network are improved, while the security level of the primary network
is enhanced concurrently.
Finally, we investigate the PLS design and analysis of reconfigurable intelligent surface
(RIS)-aided wireless communication systems in an inband underlay D2D communication
and the CR network. An RIS is used to adjust its reflecting elements to enhance the data
transmission while improving the PLS concurrently. Furthermore, we investigate the design
of active elements in RIS to overcome the double-fading problem introduced in the RISaided
link in a wireless communications system. Towards this end, each active RIS element
amplifies the reflected incident signal rather than only reflecting it as done in passive RIS
modules. As revealed in our analysis and simulation, the use of active elements leads to a
drastic reduction in the size of RIS to achieve a given performance level. Furthermore, a
practical design for active RIS is proposed.


identifier: Crowley, Joe <https://research.library.mun.ca/view/creator_az/Crowley=3AJoe=3A=3A.html>   (2021) An introvert in the midst: a poetic self-study of the lived experiences and challenges of an introverted teacher.  Masters thesis, Memorial University of Newfoundland.

abstract: This research represents a highly personalized account of the complexities, interpretations, and reflections on the experiences and challenges faced by an introverted teacher in the workplace. Positioning myself as both the subject and the researcher in the social context of a middle school setting propelled this self-study of my experiences as a teacher in the Avalon Region of Newfoundland and Labrador (NL). Through an insider’s vantage point, I have chronicled and traced my own experience using a combination of qualitative methodologies: autoethnography and poetic inquiry. These genres of qualitative research, complemented by a phenomenological lens, bring the reader closer to the lived experience of the author. This study supports the notion that poetic inquiry, critical reflection, and personality investigation can prove to be valuable tools for empowering teachers and helping to improve their understanding of self, their professional practice, and their relationship with their students. Using self-study to explore my experiences with introversion helped to unfetter my own unique voice and convey personal thoughts and emotions that led to findings that contribute to the knowledge base of the introverted experience as a sociological phenomenon.


identifier: Seyedfarizani, Sara <https://research.library.mun.ca/view/creator_az/Seyedfarizani=3ASara=3A=3A.html>   (2022) Abrasion and impact resistance of concrete under different curing conditions.  Masters thesis, Memorial University of Newfoundland.

abstract:
This study aims to assess the mechanical properties, impact resistance, and abrasion resistance of a series of self-consolidating concrete (SCC) and normal vibrated concrete (NVC) mixtures under different curing conditions. The studied variables included coarse-to-fine (C/F) aggregate ratio (0.7 and 1.2), water-to-cement (w/c) ratio (0.4 and 0.55), the addition of 0.35% steel fibers (SFs), and the use of different supplementary cementing materials (SCMs) types (metakaolin (MK) and silica fume (SLF)). The research program was divided into three stages. The first stage included trial mixtures to optimize a number of SCC mixtures with different proportions. In this stage, the appropriate percentages of SCMs (MK or SLF) and the maximum percentage of SFs that can be used to develop successful SCC were optimized. The second stage included evaluation of the compressive strength, splitting tensile strength, and impact resistance of the optimized mixtures. The third stage investigated the flexural strength, modulus of elasticity, and abrasion resistance of the same optimized mixtures. All studied samples were cured under four different curing conditions, including moisture curing conditions at 23º C, air curing at 23º C, and cold temperatures curing conditions at +5º C and -10º C.
Curing concrete at +5º C showed significant reductions in the abrasion strength, compressive strength, splitting tensile strength (STS), and impact resistance, when compared to moisture curing at 23º C. The magnitude of these reductions significantly increased when curing concrete at -10º C. Mixtures with higher C/F ratio, or higher w/b ratio, or mixtures with SFs or SCMs were more affected by the cold curing compared to the control mixture. The results also showed that cold temperature curing had a more pronounced negative effect on the impact resistance and STS compared to the compressive strength.


identifier: Le, Ba Thuong <https://research.library.mun.ca/view/creator_az/Le=3ABa_Thuong=3A=3A.html>   (2021) Functions and dynamics of boreal bog vegetation under global changes.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Vegetation with a dominance of Sphagnum and low cover of vascular plants have been recognized as a core component that controls several biogeochemical processes and vital services of boreal bogs, especially in greenhouse gas emissions. The boreal bog plants are long-term adapted to cold, low available nutrient conditions. Therefore, global warming and increases in nitrogen (N) availability may change the boreal bog vegetation and alter the primary services of these boreal ecosystems. This study utilized long-term field experiments to examine the function of vegetation composition in regulating N₂O emissions and dynamics of boreal bog vegetation to the projected global changes. Results show that graminoids accelerate N₂O emissions from boreal bogs under N-enriched conditions. This study also indicates that the long-term warmer (W) and N-enriched conditions enhance vascular plant growth, especially graminoids. By contrast, these environmental changes result in rapid losses of Sphagnum in boreal bogs. Vascular plants mitigate the decline of Sphagnum, although the facilitation by vascular plants can not eliminate the decreases in Sphagnum mosses due to the warming and high N availability. These findings suggest that vegetation might switch to the dominance of vascular plants under warmer, N-enriched conditions, stimulating N₂O emission in boreal bogs.


identifier: Downing, Victoria <https://research.library.mun.ca/view/creator_az/Downing=3AVictoria=3A=3A.html>   (2021) Design and construction of a sulfur dioxide gas permeation device and further screening of metal-organic frameworks for the removal of harmful gases from the air.  Masters thesis, Memorial University of Newfoundland.

abstract:
Metal-organic frameworks (MOFs) are a class of porous materials comprised of metal nodes and organic linkers. These tunable materials possess high accessible surface area, making them attractive for a variety of applications (e.g., gas separations, gas storage, and catalysis). The primary focus in this thesis has been to examine the experimental design and the application of MOFs for the sorption and separation of harmful gases. This thesis will focus on two different topics.
Firstly, the application of MOFs for the sorption of sulfur dioxide (SO₂) gas was explored. SO₂ is a criteria air pollutant, being one of the most common air pollutants monitored by the government. SO₂ gas is harmful to both human health (e.g., respiratory ailments) and the environment (e.g., acid rain). The primary anthropogenic source of SO₂ in the environment is the combustion of fossil fuels. Existing pre- and post- combustion methods for the removal of SO₂ are costly and are unable to meet stringent environmental regulations. These drawbacks in pre-existing methods/materials increase the demand for more effective and lower cost alternatives. The challenge with studying SO₂ adsorption/separation is in the toxicity and corrosive nature of the gas. This makes it difficult to study SO₂ at environmental concentrations. With that in mind, we aimed to create a tunable SO₂ source to test MOFs for their sorption potential of gaseous SO₂. Chapter 2 will thoroughly discuss the experiments that were implemented in creating an SO₂ gas source.
Secondly, MOFs were investigated for their potential to separate carbon monoxide (CO) from other gases on the basis of size exclusion. Our primary interest has been to separate
carbon dioxide (CO₂) from CO. This is due to the risks associated with incomplete combustion that leads to formation of CO. CO is a colorless and odorless gas that, even at low concentrations, can be extremely detrimental to human health. Therefore, newly discovered MOF systems were investigated for their ability to sieve CO from other common gases (CO₂ and N₂) via their unique pore apertures. The synthesis, crystal structure, and separation capabilities of both Zn₃(NH₂BDC)₃DABCO and Zn₂Cd(NH₂BDC)₃DABCO will be discussed in-depth in Chapter 3.


identifier: Katayama, Yuka <https://research.library.mun.ca/view/creator_az/Katayama=3AYuka=3A=3A.html>   (2021) Bilingual phonological development: a case study of Japanese-English bilingual acquisition.  Masters thesis, Memorial University of Newfoundland.

abstract: Despite many decades of modern research on child language acquisition, our understanding of how humans acquire languages is still incomplete and, as such, subject to theoretical debates. Particularly, concerning the process of language acquisition in bilingual children, there are two opposite views within the scientific literature; some scholars support the view that certain properties of one of the two languages of these children may affect the acquisition of the other language, while other scholars do not find any evidence for such phenomenon. In this thesis, we examine how a Japanese-English bilingual child, code-named Naoki, developed consonants and consonant clusters in word-initial syllable onsets, word-final syllable codas as well as word-medial geminates and coda-onset clusters. The results from this longitudinal study suggest that while Naoki displayed high accuracy in his productions of syllable onsets in both Japanese and English, his development of syllable codas in both languages was affected by the Japanese constraints on sound distributions within this position.


identifier: Swirski, Zach <https://research.library.mun.ca/view/creator_az/Swirski=3AZach=3A=3A.html>   (2021) Black holes boxing: Sartre on love.  Masters thesis, Memorial University of Newfoundland.

title:
Black holes boxing:
Sartre on love

abstract:
Sartre’s phenomenology of love reads as calloused, narcissistic, and antiquated. He contends that the ideal of love is the ontological unification of the lover and the beloved and because this ideal can never be fulfilled, both theoretically and in practice, love is always destined to devolve into hate. Love is conflict. For this project, I will be looking to critique Sartre, to explore the possibility that love does not necessarily lead to hate, and that a positive love is possible. I will begin, in the first chapter, by doing a brief autopsy on some key components of Sartre’s philosophy. First, his inheritance of Cartesian ontology of consciousness, his rejection of the cogito as the foundation of this ontology, and his use of Husserlian intentionality. The monad of consciousness will come into vision through analysis of the expressions ‘in-itself’ and ‘for-itself’. Sartre owes a debt here to Hegel, both in terminology and in the meaning of the designations of master and slave. However, I will rebuild the idea that Sartre is to be read as some sort of neo-Hegelian in his treatment of the Other and conflict. Consciousness is not mediated at the level of being by the Other, but at the level of identity. The lover – beloved relationship is founded in the look; this is foundational to the perceived conflict of romantic relationships. I will give a full exegesis of Sartre’s chapter in BN on love, where he affirms that love will always devolve into hate.
Comparing Deleuze and Guattari’s faciality with Sartre’s look is the focus of my second chapter; these are not two opposite modes of subjectivity, but rather two different speeds of subjectivity. I open a door to a Sartrean-Deleuzeian mode of lover-beloved relationships. The goal now becomes combining Sartre and Deleuze to create a positive romantic interface. This is done through a phenomenological reading of Deleuze’s “Description of Woman”, where he contends that desire fundamentally changes the phenomenological experience of the Other, and the Other does not present an external world, but an internal one. This leads us to conclude that through bringing Sartre and Deleuze together, love is not defined by its failure of unification, but rather through its ability to draw a self and an Other together in experiencing the internal world of each other as a ‘we,’ rather than as two rival ‘I’s’.


identifier: Friedetzky, Claudia <https://research.library.mun.ca/view/creator_az/Friedetzky=3AClaudia=3A=3A.html>   (2022) Evaluating the readiness of three States in the Northeastern United States to adapt important natural resources systems to climate change: practical and theoretical considerations.  Masters thesis, Memorial University of Newfoundland.

abstract:
In the last decade, governments have made advances in the development and adoption of climate
adaptation programs. With the rise of these programs, scholarly efforts have emerged to assess
and evaluate their effectiveness and quality. Thus, researchers have developed and applied a
range of climate adaptation evaluation approaches to gauge adaptation progress. In this thesis, a
climate adaptation evaluation approach developed by Ford and King (2015) — the adaptation
readiness framework — was applied to assess the readiness of three Northeastern US States –
Massachusetts, New Hampshire, and Maine – to adapt the natural resources systems located
within their boundaries to climate change. To enable the adaptation readiness evaluation, the
indicators in the adaptation readiness framework were revised to fit the context of this study
shaped by scale and governmental system. Systematic reviews of the scholarly and grey
literature were pursued. The revised indicators were used for the coding of documents.
Indicators were then scored based on ordinal rankings. Results demonstrated that Massachusetts
had the highest level of climate adaptation readiness, New Hampshire the second highest and
Maine the lowest climate adaptation readiness. It was found that political leadership – one of the
factors in the framework – strongly correlates with climate adaptation readiness, and that high
levels of climate adaptation readiness are associated with government centralization. The
conceptual strengths of the framework include its ability to illuminate adaptation deficits, and
adaptation policy patterns and structures. Its weaknesses stem from the vagueness of the
underlying definition of adaptation. Rather than measuring adaptation progress, the adaptation
readiness framework measures the extent to which governments have established programs that
fall under the category of adaptation as “adjustments”.


identifier: Kopbayev, Alibek <https://research.library.mun.ca/view/creator_az/Kopbayev=3AAlibek=3A=3A.html>   (2022) Fault detection and diagnosis using hybrid artificial neural network based method.  Masters thesis, Memorial University of Newfoundland.

abstract: This thesis proposes a novel approach to fault detection and diagnosis (FDD) that is focused on artificial neural network (ANN). Unlike traditional methods for FDD, neural networks can take advantage of large amounts of complex process data and extract core features to help detect and diagnose faults. In the first part of this work, a hybrid model was developed to improve efficiency and feasibility of neural networks by combining Kernel Principal Analysis (kPCA) and deep neural network. The hybrid model was successfully validated by Tennessee Eastman Process. The second part of the research focuses on a specific application to gas leak detection and classification. In this scenario, a convolutional network (ConvNet) was used as a feature extraction tool prior to network training due to the visual nature of data. The model was shown to accurately predict leaks and leak sizes; furthermore, further model optimizations were performed and evaluated. The proposed approach is superior to other FDD approaches due to its performance and optimization flexibility.


identifier: Mayo, Jordan D. <https://research.library.mun.ca/view/creator_az/Mayo=3AJordan_D=2E=3A=3A.html>   (2022) Definition of detection and reaction boundaries for autonomous marine vessels.  Masters thesis, Memorial University of Newfoundland.

abstract:
Definition of Detection and Reaction Boundaries for Autonomous Marine Vessels investigates
the possibility of using a time-based self-separation method for safely navigating
a controlled vessel with oncoming vessels and obstacles, which may or may
not adhere to the appropriate guidelines for encounter navigation with another vessel.
The simulation uses a validated model of a test vessel in order to accurately describe
vessel dynamics when operating at a given desired speed, with an identical oncoming
vessel. The simulation is used to calculate the last possible time before a collision
would occur that the controlled vessel must begin manoeuvring in order to maintain
a desired amount of separation with the intruder, regardless of whether the vessel is
navigating properly or not. The algorithm was also tested in varying environmental
conditions through a Monte Carlo simulation in order to confirm the results in
non-calm water situations.
All results presented are with both the controlled vessel and intruding vessel travelling
at 10 knots with a fixed maximum turn rate. There is a desired separation
boundary of twice the length of the vessel from the centre point of the vessel, in all
directions. The effects of changing the speed and size of the separation boundary were
analyzed, and it was found that increasing the size of the separation boundary results
in the vessel requiring more time to manoeuvre, while increasing the speed decreases
the time required. Each of these relations between the time required to safely manoeuvre
and the changing parameters are approximately linear. From the simulations,
it was determined that the test vessel in a head-on encounter scenario must begin manoeuvring
approximately 3 minutes with a non-compliant intruder and slightly more
than 2 minutes for a compliant intruder. For a crossing scenario, the controlled vessel
must begin to manoeuvre at least approximately 8 minutes prior to the closest point
of approach for the intruder in order to maintain the desired separation. Lastly, for an
overtaking scenario, with the intruder travelling at 80% of the speed of the controlled
vessel, the controlled vessel must begin to manoeuvre once again, approximately 8
minutes prior to the closest point of approach. Note that in certain environmental
conditions, more time may be required to manoeuvre effectively.


identifier: Love, Ryan <https://research.library.mun.ca/view/creator_az/Love=3ARyan=3A=3A.html>   (2021) The impacts of glacial runoff and pCO₂ on centennial-to millennial-scale climate variability during the last glacial cycle.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Freshwater is hypothesized to have a critical role in previous centennial-to
millennial-scale climate variability(CMCV),e.g. Dansgaard Oeschger events, the
Younger Dryas, and may play a central role in future climate change as ice sheet
and glacier melt accelerates. Similarly, anthropogenic climate change demonstrates
the need to understand the impact of carbon dioxide (pCO₂) on climate variability.
The relationship between freshwater and rapid climate change in the paleoclimate
records has been a subject of intense study, but past approaches have generally relied upon an approximation of freshwater entering the oceans via wide bands in the North Atlantic in `hosing' experiments. This design element of hosing experiments, which supports the relationship between freshwater and climate cooling, artificially
amplifies the climate response by introducing freshwater directly over sites of deep
water formation. As well, previous studies have yet to characterize the role of either pCO₂ or freshwater on CMCV under appropriate boundary conditions.
This thesis explores the impact two likely controls of CMCV, freshwater and
pCO₂ concentrations. I achieve this by first determining where coastally released
freshwater is transported using an eddy permitting ocean model configured for the
the Younger Dryas interval during the last deglaciation. It is found that by explicitly resolving features important for the transport of coastally released freshwater, such as mesoscale eddies, that hosing overestimates the amount of freshwater transported to sites of deepwater formation by 2-4x. Next, using these results I then derive a novel method of freshwater injection, the freshwater fingerprint, and examine the relative climate impact of different freshwater injection distributions. In comparing the fingerprint method against both conventional band hosing and regional injection methods I conclude that the fingerprint methodology allows for emulation of some features of the eddy permitting representation in a coarse resolution coupled climate
model. Finally, I examine the impact that pCO₂ and freshwater has on a specific
form of CMCV, Dansgaard-Oeschger events during Marine Isotope Stage 3 (MIS3),
with boundary conditions consistent with the MIS3 interval. When examining characteristics of CMCV I find that both increasing freshwater and decreasing carbon
dioxide levels lead to similar changes in interstadial & stadial durations.


identifier: Kara, Kadir Bahadır <https://research.library.mun.ca/view/creator_az/Kara=3AKadir_Bahad==0131r=3A=3A.html>   (2022) Three-dimensional forward modelling and inversion for the CSAMT method using unstructured grids.  Masters thesis, Memorial University of Newfoundland.

abstract:
Three-dimensional forward-modelling and inversion problems are investigated for the
controlled-source audio-frequency magnetotelluric (CSAMT) method and both
forward-modelling and inversion codes written. The finite-element (FE) method,
which is a numerical method for obtaining approximate solutions to boundary-value
problems, is used for forward modelling. A potential formulation, specifically the
decomposition of the electric field into vector and scalar potentials for the Helmholtz
and the conservation of charge equations, is used. Vector and scalar basis functions
are used for the potentials. The equations are discretized using the weighted residual
method, which results in a sparse linear system. Modelling domains are subdivided
into unstructured tetrahedral grids. The linear system is solved by the direct solver,
MUMPS, with LU factorization. A number of examples are presented for the
validation of the code. A minimum-structure method with Gauss-Newton iterations is
used for the inversion. Iterative preconditioned conjugate gradient and
nonpreconditioned generalized minimal residual methods are used to solve the linear
systems of equations for the model updates. These solvers do not request explicit
calculations of the matrices; therefore, this significantly reduces memory demand.
Three benchmark tests are presented to verify the inversion code.


identifier: Baah, Christabel Nyarwaa <https://research.library.mun.ca/view/creator_az/Baah=3AChristabel_Nyarwaa=3A=3A.html>   (2022) Gendered attitudes and women's political interest: the cases of South Africa and Ghana.  Masters thesis, Memorial University of Newfoundland.

abstract:
This thesis situates the issue of women’s political representation in a socio-cultural context by
examining the relationship between gendered attitudes and women’s political interest in South
Africa and Ghana. South Africa represents an African country with higher women’s legislative
representation, and Ghana represents a country with low women’s legislative representation on
the continent. “Women having less interest in politics than men” is a well-researched area in
political attitudes studies (Campbell and Winters, 2008: Anderson, 1975; Burns 2001; Fox and
Lawless, 2010). However, less is known about the underline cause of this difference. This
thesis argues that socio-cultural factors such as patriarchy, gendered roles, and cultural beliefs
are to be blamed for the presence of “gendered attitudes,” which have consequently affected
“women’s interest in politics.” I use data from the World Values Survey and bivariate statistics
to answer the following questions: (1) are South African and Ghanaian women less interested
in politics than men? (2) do gendered attitudes affect women’s political interest in Ghana and
South Africa? Findings from the analysis reveal, (1) women in Ghana and South Africa are
generally less interested in politics than men. (2) there is a relationship between gendered
attitudes and women’s political interest in Ghana and South Africa. Findings from this thesis
provide a start to a meaningful conversation. More research is needed to better understand the
relationship between gendered attitudes and women’s interest in politics.


identifier: Ramlackhansingh, Jinelle N. <https://research.library.mun.ca/view/creator_az/Ramlackhansingh=3AJinelle_N=2E=3A=3A.html>   (2022) Professional identity development of pre-clerkship medical students: a critical analysis.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
This dissertation examines how the undergraduate medical education learning environment shapes the development of “the good doctor” professional identity amongst pre-clerkship medical students. The research addresses the gap in scholarship on how the hidden curriculum shapes medical professional identity. The research highlights how the beliefs and practices of students are shaped not by a value-neutral curriculum, but out of and in response to official ideologies perpetuated in the broader learning environment (the “culture” of medical school) in ways that are often hidden.
This research was based on a two-year longitudinal critical ethnographic case study of one Canadian medical school. Data collection included focus groups with a core group of students during their first two years of medical school. This was supplemented by interviews with administrative staff and faculty, and observation of the medical school governance meetings. Undergraduate medical education training was examined from students’ perspectives, focusing on how the formal, informal, and hidden curricula shape professional identity. The critical theoretical frameworks of Pierre Bourdieu and Michel Foucault were used to analyze the complex relations of power and influence in pre-clerkship education. Particular attention was paid to how power intersects with the culture of medicine as the identity of a medical professional is constructed. The results show how official ideologies of what it means to be “the good doctor” as prescribed in the national CanMEDS roles and mandated locally through medical school governance structures, are in conflict with and resisted through the counter-ideologies promoted through the hidden curriculum.
This research has important implications for curriculum planning in medical education. The findings provide compelling evidence that the formal curriculum must be designed to account for the effects of a hidden curriculum. Specific recommendations are: (1) Medical students would benefit from having a pedagogical space in the formal curriculum to critically reflect on their experiences and the various ideologies and counter-ideologies of “the good doctor” that are shaping their identity; and (2) Establishing communities of practice as a pedagogical space model, would be a useful framework for facilitating this approach, supporting students to navigate the hidden curriculum and negotiate their own professional identity.


identifier: Herat, Nehara Shamistra <https://research.library.mun.ca/view/creator_az/Herat=3ANehara_Shamistra=3A=3A.html>   (2022) Short-interval intracortical inhibition to the triceps brachii during arm cycling.  Masters thesis, Memorial University of Newfoundland.

abstract: Non-human animal work shows the existence of a network of spinal cells called central pattern generators (CPGs) that partially control locomotion. Indirect evidence shows that CPGs also contribute to human locomotion. However, humans require the integration of descending input from cortical motor-related areas for the generation and control of locomotive outputs. Unfortunately, the cortical circuits that modulate the excitability of the motor cortex during locomotor outputs are not well understood. Short-interval intracortical inhibition (SICI) is one circuit thought to help inhibit the motor cortex. The majority of work done to understand SICI has utilized isometric contractions, but evidence suggests that cortical circuits are modulated differently during locomotor outputs. Our lab has shown the presence of SICI to the biceps brachii during arm cycling, but did not investigate SICI to the triceps brachii, another vital muscle required for arm cycling. Examining SICI to the triceps may improve knowledge translation to neurological rehabilitation programs that utilize arm cycling.


identifier: Gregory, Keegan Patrick <https://research.library.mun.ca/view/creator_az/Gregory=3AKeegan_Patrick=3A=3A.html>   (2022) Analyzing seasonal effects on logistical risks associated with servicing an oil production facility in the Flemish Pass.  Masters thesis, Memorial University of Newfoundland.

abstract:
There are field discoveries in the oil and gas industry that require significant investment to develop, and the Bay du Nord and Baccalieu fields in the Flemish Pass are no exception. Long-distance, deep-water production facilities are expected to increase marine logistical risks in an area that already is known for its harsh weather conditions, and the implications of not properly understanding and mitigating these risks are the safety of those involved in the operations and millions of dollars in material damage.
This research is focused on more accurately modelling the seasonal effects of changing environmental conditions on the failure rate of marine logistics operations. This work is an extension of previous research in the field and is focused on further model development and refinement. Fault tree and Bayesian network models are compared, with applicable data uncertainty considerations. Model refinements to reflect conditional dependencies more accurately, and a process for establishing mitigation efforts and accident prevention strategies are then proposed. This thesis details data acquisition, application of seasonal conditions inputs, and a quantitative technique for analyzing pre-emptive barriers to logistics operation failure. The final product is a strategy for estimation of logistics operation failures


identifier: Lee, Ryan <https://research.library.mun.ca/view/creator_az/Lee=3ARyan=3A=3A.html>   (2022) Self-paced study and word dimensionality in metacognition.  Masters thesis, Memorial University of Newfoundland.

abstract: The mechanisms underlying metacognitive monitoring-control relationships for emotional information are unclear in the existent literature. We conducted two online studies of university students measuring metacognition for emotional words across three related dependent variables: study time, judgements of learning (JOLs) and recall. We used a repeated measures design with free-recall testing for both experiments. In Experiment 1, words were distinctly categorized based on emotional valence (negative, neutral, and positive). In Experiment 2, words were categorized based on arousal (low, medium, and high). In the first experiment we found that both negative- and positive-valenced words were higher than neutral-valenced words in both JOL rating and recall. In the second experiment we did not find an effect of arousal on JOL ratings or recall. These data suggest that valence and arousal have conceptually distinct roles in metacognition within the mixed-list, three-level design we used. In the second experiment only, we also found that study time was reduced between blocks. Participants were surveyed on their explicit metacognitive beliefs underlying their study habits. Participants tended to explicitly notice the valence manipulation but did not notice the arousal manipulation. Participants also tended to qualify emotional words as being more relatable to themselves, perhaps hinting at how our memory systems engage with emotional information. Further qualifications about how individuals’ metacognitive strategies vary based on word quality are discussed.


identifier: Hacker Teper, Sean M. <https://research.library.mun.ca/view/creator_az/Hacker_Teper=3ASean_M=2E=3A=3A.html>   (2022) Assessing trophodynamics of a Newfoundland rhodolith (Lithothamnion glaciale) bed using lipid, fatty acid, and stable isotope analyses.  Masters thesis, Memorial University of Newfoundland.

abstract: Rhodoliths (free-living, non-geniculate red coralline algae growing as balls, branched twigs, or rosettes) often form dense aggregations, termed rhodolith beds, at depths of up to 150 m in tropical to polar seas. The important contribution of rhodolith beds to marine biodiversity and global calcium carbonate production has, in part, triggered the recent increase in number of studies of factors and processes regulating their structure and function with, however, little attention to feeding relationships. The present thesis investigated trophodynamics of a rhodolith (Lithothamnion glaciale) bed in St. Philip’s, Newfoundland (Canada) with a combination of lipid, fatty acid, and stable isotope analyses. I quantified lipid composition, energy transfer, essential nutrients, and seasonal and spatial variability among six dominant echinoderm, bivalve, gastropod, and polychaete species, two algal species, seawater, and sediment beneath individual rhodoliths. Results suggest strong benthic-pelagic coupling in that rhodolith bed organisms utilize phytoplankton, especially diatoms, as a main food source during blooms. I identified three distinct trophic levels among associated macrofauna and flora (producers, suspension/filter feeders and grazers, and predators), while discovering a potential resource partitioning relationship among organisms in which first- and second-order consumers share a common resource (diatoms or kelp). Diets shifted in response to seasonal food availability and life history requirements, but were unaffected by riverine input proximity. Based on my findings, I conceptualized a partial food web detailing the interpreted linkages among food sources and organisms in the studied rhodolith bed. This proposed food web delineates relationships among organisms and essential nutrients in cold water systems, while demonstrating the interconnectedness of various rhodolith bed components.


identifier: Eissa, Riad Omar Abosalahe Omar <https://research.library.mun.ca/view/creator_az/Eissa=3ARiad_Omar_Abosalahe_Omar=3A=3A.html>   (2021) Effect of biochar on soil fertility, nitrate losses, dissolved organic carbon, forage crop production and greenhouse gas (GHG) emissions.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
The growing need to improve soil fertility and enhance crop production has led to increase in the nitrogenous (N) fertilizer use, which could result in detrimental effects due to the possible increase in greenhouse gas (GHG) emissions and nitrate leaching losses. Therefore, there is a pressing need to address the negative environmental effects of nitrogen fertilizer use through better management practices. Biochar applications to the agricultural soils have been recognized as a unique strategy for improving soil fertility, mitigating GHG emission, enhancing carbon sequestration, and plant nutrient use efficiencies by increasing nutrients uptake while reducing the leachate losses. Considering multidimensional benefits of biochar, the current study investigated the effects of different biochar application rates on podzolic soil fertility, GHGs mitigation potential, soil nitrogen dynamics, crop productivity and forage quality in eastern Newfoundland podzolic soils. The first experiment was conducted to assess the nitrate adsorption potential of four different biochar feedstocks including, spruce-bark biochar at 550⁰C (SB550), hardwood biochar at 500⁰C (HW500), fir/spruce biochar at 427⁰C (FS427), and softwood biochar at 500⁰C (SW500). The results showed that SB550 has the highest nitrate adsorption capacity (184 mg g⁻¹) among others. The second experiment was conducted in a greenhouse with five rates of SB550 and two N application levels to (i) investigate the capability of biochar application for improving the soil fertility, forage production, forage quality, and nutrient uptake, (ii) assess their effects on soil total nitrogen (TN), nitrate (NO₃⁻), ammonium (NH₄⁺) dynamics and dissolved organic carbon (DOC). Results indicated that biochar application significantly improved soil pH, Soil Organic Matter (SOM), Cation Exchange Capacity (CEC), and available nutrients in the soil. Moreover, SB550 biochar has significantly reduced NO₃⁻, NH₄⁺, TN, and DOC in the leachate compared to the control treatment. The third experiment was conducted under field conditions. Four rates of
HW500 biochar applications, with three levels of nitrogen fertilizer applications (Urea 46-0-0) that were applied at the rates of 0, 65 and 130 N kg/ha to the Festulolium forage crop field. Biochar application has significantly reduced GHG emissions and increased the Festulolium productions. Thus, biochar application has shown to be a promising technique for sustainable agricultural management practices in the eastern Newfoundland Podzolic soil.


identifier: Chakraborty, Sudipta <https://research.library.mun.ca/view/creator_az/Chakraborty=3ASudipta=3A=3A.html>   (2022) Behavior of branched buried MDPE gas distribution pipes under relative axial ground movements.  Masters thesis, Memorial University of Newfoundland.

abstract: The performance of medium density polyethylene (MDPE) gas distribution pipes subjected to relative ground movements has been a significant concern to the utility owners and companies. The tee-joints (tapping tee) and the lateral branches, common in gas distribution piping systems, may increase the effects of ground movement caused by various geohazards such as landslides, earthquakes etc. Most ground movement scenarios depict leak/stress concentration near the tapping tee of the branched pipe system. However, limited studies are currently available in the literature on the soil-pipe interaction of branched pipes during ground movement. Thus, the complex interactions of the pipe, the tee-junction, and the branch with surrounding soil are not well-understood. This thesis presents an experimental investigation of different configurations of 42.2-mm and 60.3-mm diameter branched buried MDPE pipes under relative axial ground movement. Tests with different positions of the tee-joint with respect to the pulling end of the pipe and varying densities of sand are conducted using the laboratory facility at Memorial University of Newfoundland. Pipe wall strains and soil pressures around the pipes are measured during the tests to capture the mechanism of soil-pipe interaction. Subsequently, an additional test is done with the tapping tee only (without the branch pipe) to identify the contribution of the branch pipe to soil resistance and pipe wall strain. The study explores the contribution of the trunk pipe, the tapping tee, and the branch pipe separately on the axial pulling force. Test results reveal the possibility of localized strain occurring on the trunk pipe near the tee. The anchoring effects of the tee and the branch significantly affect the soil resistance and the strain distribution on the trunk pipes.


identifier: Meshkin Kiya, Sara <https://research.library.mun.ca/view/creator_az/Meshkin_Kiya=3ASara=3A=3A.html>   (2021) Heimat und Nostalgie in Meral Kureyshis Elefanten im Garten und Melinda Nadj Abonjis Tauben fliegen auf.  Masters thesis, Memorial University of Newfoundland.

abstract:
Für meine Arbeit habe ich die Romane Tauben fliegen auf (2010) von Melinda Nadj Abonji und Elefanten im Garten (2015) von Meral Kureyshi ausgewählt. Beide Romane können der Secondo Literatur zugeordnet werden, welche sich mit Themen wie Heimat, Erinnerung, Sprache, einer dualen Identität und Entfremdung beschäftigen. In diesen zwei Familienromanen verarbeiten die Autorinnen ihre persönlichen Migrationserfahrungen. Es werden die Integrationsschwierigkeiten der zweiten Generation von Einwanderern in der Schweizer Gesellschaft dargestellt, welche mit denen der ersten Generation nicht deckungsgleich sind.
In der vorliegenden Arbeit behandele ich die Frage, ob die Hauptfiguren in diesen Texten sich in der Schweiz heimisch fühlen können. In meiner Arbeit untersuche ich das Konzept „Heimat“ in diesen Romanen mit Hilfe der Theorien von Svetlana Boym (Nostalgie), Leslie Adelson (Dazwischen), und Margit Zinggeler (Secondo/a Literatur). In Tauben fliegen auf und Elefanten im Garten ist die Idee der Heimat nicht von territorialen, ethnischen, und nationalen Merkmalen eingegrenzt. Es gibt weder eine Zugehörigkeit zur alten Heimat noch zu der Schweiz, sondern nur Erinnerungen an bestimmte Personen und die Kindheit. Anstatt weiterhin nach einer territorial verankerten Heimat zu suchen, entscheiden sich die beide Protogonistinnen für einen Selbst(er)findungsprozess. Die Autorinnen zeigen, dass Heimat der Ort ist, an dem man sich selbst (er)finden kann.


identifier: Tati Padou, Martinet-Sayi’Mone <https://research.library.mun.ca/view/creator_az/Tati_Padou=3AMartinet-Sayi==2019Mone=3A=3A.html>   (2021) Role of dynein and kinesin in viral proliferation & dynein inhibitors.  Masters thesis, Memorial University of Newfoundland.

abstract:
Dynein and kinesin are motor proteins involved in the retrograde and anterograde, respectively, transport of cargoes, including viral genomes following infection. Current literature reveals that both proteins play critical roles in ensuring successful viral proliferation. The literature also shows that the motor proteins are involved in the immunological response of host cells. Small-molecule inhibitors of kinesin and dynein inform of the function of the proteins during viral proliferation and immunological response.
The investigation of the binding profile of small-molecule inhibitors of dynein, namely, ciliobrevin and analogues as well as dynapyrazole A and B, and the protonated forms of the lead compounds at the AAA1 binding site of dynein revealed the identity of the residues interacting with the inhibitors. This research project also analyzed the effect of isomerization of ciliobrevin on its binding profile, the impact of protonation of lead compounds on the binding affinity of the inhibitors, and the intramolecular interactions in dynein. The results suggest a potential residue in the AAA1 subunit of cytoplasmic dynein 1 that could be involved in the ‘glutamate switch’ mechanism, which according to the literature, has not been observed in dynein 1.


identifier: Chen, Yifu <https://research.library.mun.ca/view/creator_az/Chen=3AYifu=3A=3A.html>   (2021) Machine learning based approaches for classification of oil spills and microplastics in marine environments.  Masters thesis, Memorial University of Newfoundland.

abstract:
Environmental modelling is an important approach of environmental engineering and management since it helps gain better understanding of environmental problems and impacts and facilitate environmental decision-making processes. However, because of the intricate conditions enormous data, diverse uncertainties, and various standards and requirements, environmental modeling is usually sophisticated and challenging. This study aimed to develop the novel modelling approaches by integrating machine learning (ML) into analyzing tabular and image datasets for environmental applications.
Firstly, a data-driven binary classification approach was developed to analyze oil fingerprinting. After comparing six different machine learning algorithms on five different biomarkers, random forest classifier was found as the most effective and accurate model to distinguish weathered chemically dispersed and non-dispersed oil from the dataset of diamantanes. The developed model was approved to be capable of aiding oil fingerprinting under the studied conditions. It showed the good value of ML methods in environmental modeling especially for oil spill response research and practice.
Secondly, an integrated approach by combing the strengths of convolutional neural networks and improved deep convolutional generative adversarial networks was proposed to classify microplastics and oil-dispersant agglomerates (MODAs) with diverse weathering conditions. The f score and model accuracy suggested the robust prediction from the trained model on the dataset of MODAs with different weathering degrees. The results could provide a better understanding of microplastics’ effects on oil fate and transport during a marine oil spill. The proposed approach also presented the high potential of facilitating image-related classification work in environmental fields.
This dissertation not only developed two new ML based modelling approaches for environmental applications in oil fingerprinting and oil/microplastics classification, but also demonstrated the high value of ML methods and deep neural networks in processing experimental data for supporting environmental engineering and management.


identifier: Amin, Md. Tanjin <https://research.library.mun.ca/view/creator_az/Amin=3AMd=2E_Tanjin=3A=3A.html>   (2022) Multivariate data-based safety analysis in digitalized process systems.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Chemical process industries are vulnerable to accidents due to their inherent hazardous nature, complex operations, and growing size. Although the control system works as the first safety layer and is designed to maintain the setpoint within the safety limit, it cannot suppress all the deviations. Therefore, a warning system is used above the control layer to provide alarm(s) to the operators about unpermitted process deviations that cannot be negated by the controllers. Data-based process fault detection and diagnosis (FDD) and dynamic risk assessment (DRA) tools play a pivotal role to ensure that any significant process deviation is efficiently captured and necessary maintenance has been done to restore the process to normal operating mode. Besides, these tools can provide a detailed analysis of failure paths which are significant to prevent a fault from propagating into an accident.
Conventional univariate monitoring is easier to implement and comes as standard with distributed control systems (DCS). This conventional approach is unsuitable in digitalized process systems due to increased close loop control, large process dimension, and complex interaction among variables. Modern process industries require techniques that can handle the complexity and scale of process plants. Timely detection of faults, diagnosis of root cause(s) of faults that affect multiple variables, and predicting a quantitative measure of consequence is vital to ensure process safety and reliability. The thesis deals with multivariate data-driven FDD and DRA for digitalized process systems. This research aims to reduce the technological gaps between the current methods and prerequisites of automated FDD and DRA tools for multivariate safety analysis.
This thesis looks at improving all aspects of FDD and DRA methods, starting from data pre-processing to consequence analysis due to fault(s). First, the effect of data pre-processing is investigated in the context of multivariate FDD. Multivariate exponentially weighted moving
average (MEWMA) is found to be an effective way of filtering process data without adversely affecting their correlation structure. The MEWMA is combined with PCA-BN, and a new method called MEWMA-PCA-BN is proposed. The developed framework can detect and diagnose the fault earlier than many contemporary multivariate process monitoring models. In this work, a novel methodology has been proposed to construct the BNs from historical fault symptoms. Second, the selection of the principal components (PCs) for the PCA-BN method is made automated; the correlation dimension (CD) is used in this regard. Also, a new methodology is proposed for developing BNs from continuous process data.
Third, the prediction of the consequences of a fault has been adapted for multivariate process systems. A novel data-driven framework has been proposed for concurrent FDD and DRA using the naïve Bayes classifier (NBC), BN, and event tree analysis (ETA). This work utilizes a multivariate fault probability from NBC for dynamic failure prediction. It overcomes the limitation of using univariate probability in DRA. Finally, this thesis looks into improving the FDD performance by capturing the correlation structure of process variables and considering the consequence analysis. The R-vine copula is used to demystify the correlation structure accurately while the ETA predicts the consequences. Unacceptable deviation of risk is used as an indicator of a fault, and subsequently, root cause(s) diagnosis is performed using density quantile analysis (DQA). Industrial, experimental, and simulated datasets are used to test and validate the performance of the developed models. This thesis is an important step for multivariate data-driven FDD and DRA research.