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How urban agriculture can mitigate urban heat island effects
Get PDFThis thesis explores the efficiency of urban agriculture (UA) to mitigate the
effects of the urban heat island UHI) effect. The thesis examines the causes and impacts
of UHI and how UA may help to lessen some of its and the different types of UA that
can be practiced in cities, which include rooftop vegetation vertical farming,
hydroponics, aeroponics and community gardens. The research was conducted by
reviewing existing literature on these topics and found that UA can help improve an
area's urban microclimates through multiple environmental mechanisms. In addition,
various economical and social benefits of UA are also presented and synthesized
Growing garden-based educators
Get PDFGarden-based learning (GBL) is resurging in popularity in reaction to a confluence of crises.
These crises, involving social inequity, vast economic disparity, ecocide, and mass extinction,
threaten human well-being and survivability of countless species. GBL is positioned by
proponents as a means of empowering participants to mitigate and adapt. Often unprepared and
unsupported, educators seek to sustain and scale success to enjoy the cornucopia of well
documented GBL benefits. Through eight in depth interviews with diverse garden-based
educators across three provinces and varied settings, we interrogated the meaning of success in
the educational garden while mapping an ecosystem of current and imagined support. Cultivating
joy, engaged learning, empowerment, and fostering healthy relationships within and between
students and their community and environment were highlighted as the primary goals of gardenbased educators. Educators interviewed desired GBL-friendly policies including funding and
infrastructure, curriculum-integrated GBL resources, training at all career stages, and
community-based support. Consequently, Faculties of Education are uniquely positioned to
cultivate and support a thriving GBL ecosystem. Ultimately, critical garden pedagogy adds to the
transformation of education to promote the well-being of all humans and diverse life on Earth
Modeling, analysis and countermeasures for attack propagation in wide area measurement systems
Get PDFPower grids are critical cyber-physical systems that employ advanced Information and
Communication Technologies (ICTs), such as Wide Area Measurement Systems (WAMSs),
to deliver the energy to end users reliably and efficiently. WAMSs are used to collect
real-time data from Phasor Measurement Units (PMUs) to improve the operator’s situational awareness, as well as to enhance real-time monitoring and control of power systems. The WAMS, however, is vulnerable to cyber-attacks due to the susceptibility of
its components—such as PMUs and Phasor Data Concentrators (PDCs)—and the lack
of embedded security mechanisms in its communication protocols. Some more-destructive
cyber-attacks, such as malware injection, can propagate themselves into the components of
a WAMS through the communication network. Thus, in such attacks, an attacker can compromise a larger number of components, resulting in more-severe consequences. Therefore,
investigating the propagation of cyber-attacks in WAMSs and devising effective counter-measures for this problem are of paramount importance. On this basis, this thesis initially
develops a model to analyze cyber-attack propagation in WAMS. Then, the impacts of the
attacker’s capability and the network operator’s defensive ability on attack propagation
are investigated in detail. Such a study can elucidate the required security measures and
defensive strategies to prevent the spread of cyber-attacks in WAMSs. Finally, a Learning-Based Framework (LBF) is developed to estimate the attacker’s capability. [...
Geochemistry and mineralization of the Archean Titan (Roaring River) intrusion, Thunder Bay, Ontario
Get PDFThe 2690 ± 3.2 Ma Titan intrusion is an approximately 7 by 3 km, roughly ovoid,
mafic-ultramafic intrusion, located just north of the inferred boundary between the
Winnipeg River and Marmion terranes. Outcrop in the area is relatively sparse, largely
due to cover from pervasive glacial till and Proterozoic diabase sills associated with the
Midcontinent Rift. Titan consists of a variety of lithologies, including leucogabbros,
melagabbros, gabbros, and pyroxenites, which are distributed throughout the intrusion.
Both mafic and felsic dikes are observed in outcrop, as are felsic breccias. Titan consists
of a single magma body, with one pulse of magma which has subsequently undergone
fractional crystallization within a closed system. This is supported by smooth linear
trends in the major element bivariate plots, with moderate amounts of scatter, and
consistent, tight primitive mantle normalized REE trends. Titan samples have a range of
(La/Sm)N from 0.7 to 3.8, a range of (Gd/Yb)N from 2.3 to 7.4, and a range of Nb/Nb*
values from 0.02 to 0.47. [...
Trends in breeding propensity of Common Loons (Gavia immer) in relation to lake water clarity in and around Algonquin Provincial Park
Get PDFProductivity of Common Loons has been in decline across most of Canada for several
decades. Many environmental factors and human impacts on the breeding grounds may
be causing the decline, and these factors are known to vary regionally. Common Loons
are visual predators and rely on the clarity of lake water to forage. The Canadian Lakes
Loon Survey and the Algonquin Park Loon Survey are used here to analyze trends in
breeding propensity in Algonquin Provincial Park and surrounding area. The Ontario
Lakes Partner Program was used to relate lake water clarity measured by Secchi depth to
observed occurrence of Common Loon chicks on four lakes with long-term data. No
decline occurs from 1982-2018 in the percent of lakes in Algonquin Park or its
surrounding area with evidence of breeding observed. There is no correlation between
water clarity and breeding propensity on the four chosen lakes. Where declines are
occurring, the potential relationship between water clarity and Common Loon
productivity should be investigated
Tripartite preparedness and response during the COVID-19 pandemic: a First Nations’ perspective
Get PDFFirst Nations and other Indigenous populations experience higher rates of infection and more
severe outcomes associated with disease and illness than is observed in the general Canadian
population (Lee et al., 2023; Pickering et al., 2023; World Health Organization, 2009). Health
inequities are rooted in and further complicated by factors such as the Indigenous social
determinants of health (ISDoH) (Reading & Wien, 2009), that reflect issues including but not
limited to inadequate or insufficient housing, lack of a potable water supply, poor access to
healthcare services, and difficulty with the transport of goods and services that are attributable to
geographic remoteness and lack of federal/provincial action. The compounded effects of the
ISDoH on First Nations peoples resulted in higher rates of morbidity and more severe outcomes
associated with the COVID-19 pandemic than was observed in the broader Canadian population
(Fleury & Chatwood, 2022; Clark et al., 2021). This qualitative research sought to understand
the ways in which 4 First Nations in Northwestern Ontario were both supported and underserved
by federal and provincial governments, and the ways that autonomous mitigation efforts were
organized and implemented by each community. [...
Black girls and school disciplinary mechanisms
Get PDFThis study explores the disproportionate discipline of Black Girls in Ontario’s K-12
publicly funded schools. The current literature exploring racially disproportionate discipline and
the school-to-prison pipeline obscures the ways in which Black females and males experience
this phenomenon together yet differently.
Semi-structured narrative interviews were conducted with seven self-identified Black
women who were able to provide retrospective reflections about their disciplinary experiences in
school. Critical analysis of the data revealed inequitable disciplinary challenges for Black girls
through educators’ lack of compassion, Black girls’ hypervisibility in their schools, and distorted
self-perceptions regarding their voices. Immediate interventions are required to address specific
disciplinary concerns for Black girls. This study concludes with recommendations offered by
participants
Blockchain and artificial intelligence enabled peer-to-peer energy trading in smart grids
Get PDFPeer-to-peer (P2P) energy trading allows smart grid-connected parties to trade renewable energy with each other. It is widely considered a scheme to mitigate the supplydemand imbalances during peak-hour. In a P2P energy trading system, users (e.g., prosumers, Electric Vehicles (EV)) increase their utility by trading energy securely with each
other at a lower price than that of the main grid. However, three challenges hinder the
development of secured P2P energy trading systems. First, there is a lack of implicit trust
and transparency between trading participants because they do not know each other. Second, P2P energy trading systems cannot offer an intelligent trading strategy that could
maximize users’ (agents’) utility. This is because the agents may lack previous trading
experience data that enable them to select an optimal trading strategy. Third, the current
energy trading platforms are mainly centralized, which makes them vulnerable to malicious
attacks and Single point of failure (SPOF). This may interrupt the transaction validation
mechanism when the system is compromised, and the central database is unavailable. [...
Mineralogy and petrology of the Good Hope carbonatite complex, Marathon, Ontario
Get PDFThe Good Hope carbonatite is located northwest of Marathon, Ontario (49° 02’ N, 86°
43’ W). It occurs along the northwest margin of the Prairie Lake complex. The objectives of this
research are to characterize the carbonate and other minerals of the Good Hope carbonatite,
use mineral compositions and textural associations to discuss the petrogenesis, and compare
the mineralogy of the Good Hope and Prairie Lake carbonatites to assess potential
relationships.
The major rock-forming minerals in the Good Hope carbonatite are calcite, ferroan
dolomite, and apatite. The apatite occurs predominantly as elongated aggregates and clasts
that define heterogeneous banding within the carbonatite. Syenite xenoliths are centimeterscale, entrained within the carbonatite, composed of K-feldspar, biotite-phlogopite, magnesioarfvedsonite, aegirine, quartz, and carbonate. The minor minerals within the carbonatite
include dolomite, K-feldspar, quartz, chlorite, magnetite, barite, biotite – phlogopite, magnesioarfvedsonite, aegirine, pyrochlore, albite, and fluorite. The accessory minerals include pyrite,
synchysite-(Ce), rutile, siderite, strontianite, thorite, parisite-(Ce), bastnaesite-(Ce), burbankite,
and zircon. [...
Experimental investigation of water entry of a solid object and sand particles
Get PDFThis thesis presents the results of two different approaches to water entry; first, in Part I, the results
of the experimental investigation of the water entry of a solid object, a thick disk in stagnant water,
are presented. The shape of the resulting surface crown in different release conditions and disks
with various geometries should be characterized. Moreover, the pinch-off time and depth of the
underwater cavity for disks with different densities in different release conditions are extracted
and results are compared in different conditions. Energy losses due to the impact are also obtained
and the results for different release heights and various disk densities are presented. A parameter
study reveals the dependence of the underwater cavity structure on the governing dimensionless
groups. The results of annular disks are also illustrated to see how a central hole can affect the
pinch-off characteristics. In addition, the effects of confinement on the characteristics of the
crown, pinch-off time, and pinch-off depth are investigated and results are compared with the
condition of removing wall effects. The wall effects highly reduced the radial and vertical velocity
of the surrounding water. Less vorticity with asymmetrical distribution is observed in the
surrounding water. Consequently, less swirling strength, and mean and turbulent kinetic energies
are observed in tanks with smaller widths. [...