Electronic Thesis or Dissertation

Solving Differential and Integro-Differential Boundary Value Problems using a Numerical Sinc-Collocation Method Based on Derivative Interpolation

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Creator (cre): Ross, Glen Charles, Thesis advisor (ths): Abdella, Kenzu, Degree committee member (dgc): Pollanen, Marco, Degree granting institution (dgg): Trent University
Abstract:

In this thesis, a new sinc-collocation method based upon derivative interpolation is developed for solving linear and nonlinear boundary value problems involving differential as well as integro-differential equations. The sinc-collocation method is chosen for its ease of implementation, exponential convergence of error, and ability to handle to singularities in the BVP. We present a unique method of treating boundary conditions and introduce the concept of the stretch factor into the conformal mappings of domains. The result is a method that achieves great accuracy while reducing computational cost. In most cases, the results from the method greatly exceed the published results of comparable methods in both accuracy and efficiency. The method is tested on the Blasius problem, the Lane-Emden problem and generalised to cover Fredholm-Volterra integro-differential problems. The results show that the sinc-collocation method with derivative interpolation is a viable and preferable method for solving nonlinear BVPs.

Author Keywords: Blasius, Boundary Value Problem, Exponential convergence, Integro-differential, Nonlinear, Sinc

2020

The Influence of Action Potentiation on the Perception of Objects Presented Near Hand

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Creator (cre): Paoletti, Adriana, Thesis advisor (ths): Brown, Liana E, Degree granting institution (dgg): Trent University
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For currently-debated reasons, perception of visual stimuli is enhanced in near-hand space compared to far-hand space. According to the action potentiation hypothesis, near-hand effects result from automatically generated potential motor responses produced upon viewing objects presented in near-hand space. This hypothesis was tested by crossing hand manipulations with two separate techniques designed to elicit action potentiation. The first series of experiments presented participants with a cueing task where images of handled objects served as the cue, and its handle compatibility was manipulated. A consistent near-hand effect was observed, but there was no evidence that the images potentiated action as there was no handle-compatibility effect. The second experiment used a visuomotor competition reaching task, which required participants to initiate reaches toward a distractor display and adjust their trajectory on the fly so as to end the reach at a later indicated target location. For every distractor presented simultaneous and competing motor responses were generated, and differences in how hand presence influenced the resolution of this competition were examined. Based on predictions made, action potentiation is unlikely to be the root cause of the near-hand effect; however, was not possible to rule out this explanation entirely. The findings of these experiments shed light both on the importance and consistency of the near-hand effect, and the difficulties associated with uncovering its nature in human populations.

2020

Predictive Digital Mapping of Soils in Kitimat, British Columbia

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Creator (cre): Olmstead, Emily Jean, Thesis advisor (ths): Aherne, Julian, Degree committee member (dgc): Watmough, Shaun, Degree committee member (dgc): Hutchinson, Tom, Degree granting institution (dgg): Trent University
Abstract:

Soil is an essential natural resource that supports provisioning services such as agriculture, silviculture, and mining. However, there is limited knowledge on forest soil properties across Canada. Digital soil mapping may be used to fill these data gaps, as it can predict soil properties in areas with limited observations. The focus of this study was to develop predictive maps of select soil physicochemical properties for the Kitimat Valley, British Columbia, and apply these maps to assess the potential impacts of sulphur dioxide emissions from an aluminum smelter, on soil properties in the Valley. Exchangeable [Ex.] magnesium, organic matter, pH, coarse fragment, Ex. potassium, bulk density, Ex. calcium, Ex. acidity, and Ex. sodium were all mapped with acceptable confidence. Time to depletion of base cation pools showed that ~240 km2 of the study area had a depletion time of 50 years or less. However, sources of base cations such as atmospheric deposition and mineral weathering were not considered.

Author Keywords: acidification, buffering capacity, Digital soil mapping, predictive mapping, regression kriging, soil properties

2019

White-Tailed Fear: The Human-Created Landscape of Fear and its Effect on White-Tailed Deer (Odocoileus virginianus) Behaviour.

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Creator (cre): Munro, Keith, Thesis advisor (ths): Patterson, Brent R, Thesis advisor (ths): Pond, Bruce A, Degree committee member (dgc): Schaefer, James, Degree committee member (dgc): Bowman, Jeff, Degree granting institution (dgg): Trent University
Abstract:

The primary method used to maintain white-tailed deer (Odocoileus virginianus) populations at densities that are ecologically, economically, socially, and culturally sustainable is hunter harvest. This method considers only the removal of animals from the population (the direct effect) and does not conventionally consider the costs imposed on deer as they adopt hunter avoidance strategies (the risk effect). The impact of risk effects on prey can exceed that of direct effects and there is interest in applying this concept to wildlife management. Deer are potential candidates as they have demonstrated behavioural responses to hunters. I explored the potential of such a management practice by quantifying how human decisions around hunting create a landscape of fear for deer and how deer alter their space use and behaviour in response. I used a social survey to explore the attitudes of rural landowners in southern and eastern Ontario towards deer and deer hunting to understand why landowners limited hunting on their property. I used GPS tracking devices to quantify habitat selection by hunters and hunting dogs (Canis familiaris) to better understand the distribution of hunting effort across the landscape. I used GPS collars to quantify the habitat selection of deer as they responded to this hunting pressure. I used trail cameras to quantify a fine-scale behavioural response, vigilance, by deer in areas with and without hunting. Human actions created a highly heterogeneous landscape of fear for deer. Landowner decisions excluded hunters from over half of the rural and exurban landscape in southern and eastern Ontario, a pattern predicted by landowner hunting participation and not landcover composition. Hunter decisions on whether to hunt with or without dogs resulted in dramatically different distributions of hunting effort across the landscape. Deer showed a high degree of behavioural plasticity and, rather than adopting uniform hunter avoidance strategies, tailored their response to the local conditions. The incorporation of risk effects into white-tailed deer management is feasible and could be done by capitalizing on a better understanding of deer behaviour to improve current management practices or by designing targeted hunting practices to elicit a landscape of fear with specific management objectives.

Author Keywords: Brownian bridge movement models, hunting, landscape of fear, resource utilization functions, risk effects, white-tailed deer

2020

Wastewater Impacts on Freshwater Mussels and Water Quality in a Tributary of the Lower Grand River in Southwestern Ontario, Canada

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Creator (cre): Hayward, Erin Elizabeth, Thesis advisor (ths): Metcalfe, Chris D, Degree committee member (dgc): Gillis, Patricia L, Degree committee member (dgc): Whillans, Tom, Degree granting institution (dgg): Trent University
Abstract:

The main goal of this thesis was to assess the potential impacts of discharges of treated effluent from a small facultative sewage lagoon serving approximately 300 residents of the Mississaugas of the Credit First Nation to freshwater mussel populations in Boston Creek, a small tributary of the lower Grand River. The current resident mussel populations inhabiting Boston Creek were assessed using semi-qualitative visual surveying methods. In addition to various population level observations, other possible point and non-point influences on water quality in Boston Creek were identified. Following this, Lasmigona costata mussels were deployed as biomonitoring organisms alongside passive samplers during the October 2017 lagoon discharge period. Time weighted average (TWA) concentrations of select Contaminants of Emerging Concern (CECs) and Polycyclic Aromatic Hydrocarbons (PAHs) were estimated from levels of these compounds accumulated on passive samplers to understand the influence of wastewater on water quality in Boston Creek. Finally, mussel tissues were analyzed for various biomarkers of exposure to contaminants. Population surveys indicated that Boston Creek supports a plentiful and diverse community of freshwater mussels and may be a refuge for the Species of Special Concern, Villosa iris. Passive sampling revealed that most PAHs measured were present at concentrations below detection limits, while CECs were typically detected at relatively low concentrations (ng/L) directly downstream of the lagoon discharge. Biomarker responses detected in Lasmigona costata generally could not be attributed to exposure to the lagoon effluent but these data may indicate response to other point and non-point sources of pollution that could be affecting resident freshwater mussel populations in Boston Creek. The mussels surveyed in Boston Creek may be displaying community level effects of exposure to other sources of pollution in the area. The results of this thesis will help in establishing water quality guidelines in the lower Grand River watershed that will assist in the recovery strategy for freshwater mussel species at risk in Ontario.

Author Keywords: Biomarkers, Biomonitoring, CECs, First Nations, Freshwater Mussels, SAR

2020

Community, Complexity, and Collapse: A Settlement Analysis of the Ancient Maya of the Contreras Valley, Belize

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Creator (cre): Forward, Kathleen, Thesis advisor (ths): Iannone, Gyles, Degree committee member (dgc): Awe, Jaime, Degree committee member (dgc): Macrae, Scott, Degree committee member (dgc): Haines, Helen, Degree granting institution (dgg): Trent University
Abstract:

The city-state of Minanha, located in west central Belize, reached its zenith and most culturally complex stage by the Late Classic period, 675-810 AD. Only a century later, its royal court "collapsed". The Contreras Valley is a small farming community located in a settlement zone south of Minanha. Decades of research at Minanha and the analysis of artifact frequencies from commoner households allow for a better understanding of the intra- and inter-community social practices occurring at the site of Contreras Valley and within the greater Minanha area. An Archaeology of Communities as well as Resilience Theory frameworks are utilized to explore the integrative social, political, and economic strategies of this commoner population. These theories are used to better understand the developmental history of the royal court from the perspective of the peripheral commoners, who sustained a population while the royal court disintegrated. Furthermore, this thesis focuses on the intersection of resilience and communities, and how the Contreras Valley experienced phases of resilience as well as vulnerability throughout its history. The resilience of this group of individuals will generate an increased cognizance of how a community copes with and continues to thrive in a climate of political chaos and instability.

Author Keywords: Ancient Maya, Archaeology, Archaeology of Communities, Artifact frequencies, Resilience Theory, Settlement pattern studies

2020

An Analysis of Hafted Biface Variability in the Kawartha Lakes and Trent River Drainage Region

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Creator (cre): Clayton, Darci, Thesis advisor (ths): Conolly, James, Degree committee member (dgc): Munson, Marit, Degree committee member (dgc): Fox, William, Degree granting institution (dgg): Trent University
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The objective of this thesis is to evaluate the temporal sensitivity of morphological variability in hafted bifaces in the Kawartha Lakes and Trent River drainage region. This provides a base of information that will enable future analyses that address the possible sources of this variability and to test the robustness of existing typological categories of hafted bifaces for relative dating. This base of information is established via the use of a principal component analysis of shape, raw material, and use-life data from a large sample of hafted bifaces in the region, using a new geometric morphometrics method designed to improve the accuracy of shape representation. The results of the analysis indicate that while certain typological categories may represent distinct morphotypes that are temporally sensitive, the majority of typological categories in the sample show high, overlapping morphological variability that cannot be confidently correlated temporally based on shape alone.

Author Keywords: Geometric Morphometrics, Morphological Variability, Ontario Archaeology, Principal Component Analysis, Project Point Morphology, Projectile Point Typology

2020

Ceramic Analysis of Jacob Island 2: Local Patterns and Regional Comparisons

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Creator (cre): Barnett, Kendra Lynn, Thesis advisor (ths): Conolly, James, Degree committee member (dgc): Moore, Jennifer, Degree committee member (dgc): Iannone, Gyles, Degree committee member (dgc): Pihl, Robert, Degree granting institution (dgg): Trent University
Abstract:

The goal of this thesis is to develop an understanding of the history of Middle and Late Woodland settlement at Jacob Island, located in Pigeon Lake in the Trent River region, through analysis of ceramic artifacts recovered during the 2016 excavation program. Using both typological and attribute based analysis. The results indicate a form of seasonal occupation. The ceramic patterning on site is broken down and fully examined for intra-site patterning and compared to concurrent regional examples. The regional comparison is carried out through statistical testing of independence. The results demonstrate both continuity and a pattern that is different than the surrounding region, supporting the concept of different expressions of materiality. These findings place JI-2 in a broader context with contemporary research in the South Eastern areas of Ontario and, in particular, the Trent River region.

Author Keywords: Ceramic Analysis, Kawartha Lakes, Ontario Archaeology, Typology, Woodland

2021

The First Time…A Second Time: Experiences of Second Virginity Loss in Lesbian, Gay, and Bisexual Individuals

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Creator (cre): Babin, Coady N, Thesis advisor (ths): Humphreys, Terry P, Degree committee member (dgc): O'Hagan, Fergal, Degree committee member (dgc): Blair, Karen, Degree granting institution (dgg): Trent University
Abstract:

The purpose of the current study was to explore virginity loss experiences in lesbian, gay, and bisexual individuals (LGB), specifically those who have had both a sexual experience with a member of a different sex and a member of the same sex. This phenomenon is what the current study is defining as second virginity loss. Participants consisted of 645 LGB self-identified individuals, the sample was approximately half women (53%) and ages ranged from 18-65. Further, six semi-structured interviews were conducted to gain a clearer understanding of LGB individuals virginity loss experiences. Of the sample, approximately 60% of each sexual orientation reported having two sexual experiences they equated with virginity loss, one with a member of a different sex, and one with a member of the same sex. Analyses of both the qualitative and quantitative data were conducted in an attempt to gain an understanding in three main areas: (1) definitions of virginity loss, (2) virginity beliefs, and (3) motivations. It was found that LGB individuals continue to hold heteronormative definitions of virginity loss, i.e. penile-vaginal intercourse, though these definitions were found to be transitional in nature. LGB individuals also seem to hold more gift related beliefs toward their same-sex experience and more stigma related beliefs toward their different sex experience, however, as shown by previous research (Carpenter, 2001, 2002), most LGB individuals highly endorsed process beliefs. Finally, motivations for virginity loss were found to be consistent with two main themes: validation and drive. Overall, this research suggests that the LGB community has a fairly complicated relationship with virginity but certainly do not feel exempt from the concept or the pressures attached. The current study is the first to explore the phenomenon of second virginity loss in LGB individuals and should be used as a foundation for future research in both first sexual experience and LGB fields to build upon.

Author Keywords: first sexual experience, LGB, mixed-methods, second virginity loss, virginity

2020

An Exploration of Attachment Influences on Rape Attitudes

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Creator (cre): Dahal, Grishma, Thesis advisor (ths): Brown, Liana, Degree committee member (dgc): Humphreys, Terry, Degree granting institution (dgg): Trent University
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While there is substantial research on the influence of adverse childhood experiences on sexual offending behaviours and attachment representations on sexual offending behaviours, few studies to date have explored how adverse childhood experiences and attachment representations act together to influence the development of rape attitudes in a non-clinical population. The purpose of this thesis was to explore how childhood experiences and attachment may help to understand the development of rape attitudes. Data were collected from 273 undergraduate students who completed self-report questionnaires pertaining to their attachment, childhood experiences and rape attitudes. Correlational and Structural Equation analyses were computed, and the results did not find support for the simultaneous influence of adverse childhood experiences and attachment representations on rape attitudes. Given that the sample was primarily female (83%), the results indicate that the outcomes of adverse childhood experiences on sexual attitudes may differ by gender. Understanding the formation of rape attitudes is important to understand the motivations behind sexual assault behaviours.

Author Keywords: adverse childhood experiences, rape attitudes

2020