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Dominance and competition: a giving-up density analysis of rank-based foraging decisions of small groups of confined bison (Bison bison)
Get PDFSocially foraging animals such as bison (Bison bison) modify their foraging
behaviour based on social status and food availability to maximize individual fitness.
Winter feeding trials were performed on juvenile bison at Stanley Hill Bison Farm in
Kakabeka Falls, ON, using a giving-up density (GUD) framework to record the densities
of a resource at which bison of various rank would cease foraging. Bison were provided
with two food sources, abundant lower-quality hay and limited higher-quality oats
mixed with blocks of wood in feeding trays. Time spent foraging from the high-quality
trays by each bison, as well as all instances of voluntary quitting and involuntary
abandonments of patches, were recorded and compared to the density of food remaining
in the trays at the end of the trials. Rank was negatively related to GUDs, with high-ranked bison ceasing foraging at the lowest GUDs. Dominants prematurely abandon
their own trays in favour of subordinates. However, lower-ranked bison forage for a
shorter time from the oats and cease foraging altogether at higher GUDs to exploit
lower-quality hay, likely to escape competition as the costs of foraging from the oats
increased. Males may also have a lower GUD than females. That high- and low-ranked
captive bison use different strategies of foraging in confined environments supports the
widely acknowledged theory that social rank has a large effect on foraging behaviour
and energetic intake, and the results of the trials quantify this through difference. This
study highlights the existence of two feedback loops: (1) a positive loop where increased
foraging efficiency reinforces rank for high-ranked bison, and (2) a negative loop
whereby low-ranked bison are forced to forage inefficiently and are thus ever more
disadvantaged against competition from higher-ranked bison
Studying the properties of engineered wood products
Get PDFGlulam and OSB are great building alternatives to typical materials in terms of
their strength, aesthetics, and economical nature. North America mostly uses Spruce,
Pine, and Fir (SPF) owing to their superior strength characteristics and accessibility. But
there is scope for underutilized species like larch, poplar, or birch to be used in Glulam
manufacturing and engineered products like OSB. The focus of this thesis is to examine
if use of the above-mentioned species will be a good alternative to typical SPF species.
It also provides an overview of those species, their general distribution and utilization.
The comparison is done based on the physical and mechanical properties of these wood
species and the 3 properties MOE (modulus of elasticity), MOR (modulus of rupture)
and density. It was found that these species have favourable strength characteristics as
compared to spruce and would be beneficial if used in the Glulam industry. This was a
preliminary study and if tested on a larger scale with advanced technology, this can help
create a more resilient lumber market, diversify Canadian wood business, and increase
Glulam industry’s efficiency
Fire performance of timer-concrete composite floor systems utilizing cross-laminated timber panels with self-tapping screws as shear connectors
Get PDFOne of the main reasons that hinder more utilization of combustible material, such as wood, as the
primary construction material in tall buildings is the required duration a structure must withstand
applied loads under fire exposure without losing its structural integrity, which is refereed to the
fire resistance rating required by applicable building codes. However, the increased availability of
cross-laminated timber (CLT) sections in Canada and its successful use in mass timber
construction have generated interest in its properties and performance when subjected to fire.
Floor systems in mass timber buildings can be more robust and span longer distances by adding a
top layer of concrete to form timber-concrete composite (TCC) floor systems when adequate shear
connections are utilized. The primary technique for shear connections in TCC systems is a wide
variety of metal connectors, with the self-tapping screws (STS) being one of the most used shear
connectors. Therefore, proper design guidelines and methodologies are needed to determine the
accurate fire resistance of TCC floor systems. Currently, there is no design procedure for the TCC
floor systems included in the Canadian Engineering design in wood standard (CSA O86-19) but
is implemented in other international design codes, such as the European codes. [...
Moreau envelopes-based personalized asynchronous federated learning: improving practicality in distributed machine learning
Get PDFFederated learning is a promising approach for training models on distributed data, driven by increasing demand in various industries. However, it faces several challenges, including communication bottlenecks and client data heterogeneity. Personalized asynchronous federated learning addresses these challenges by customizing the model for individual users based on their local data while trading model updates asynchronously. In this paper, we propose Personalized
Moreau Envelopes-based Asynchronous Federated Learning (APFedMe) that combines personalized learning with asynchronous communication and Moreau Envelopes as clients’ regularized loss
functions. Our approach uses the Moreau Envelopes to handle non-convex optimization problems
and employs asynchronous updates to improve communication efficiency while mitigating heterogeneity data challenges through a personalized learning environment. We evaluate our approach
on several datasets and compare it with PFedMe, FedAvg, and PFedAvg federated learning methods. Our experiments show that APFedMe outperforms other methods in terms of convergence
speed and communication efficiency. Then, we mention some well-performing implementations
to handle missing data in distributed learning. Overall, our work contributes to the development of
more effective and efficient federated learning methods that can be applied in various real-world
scenarios
The influence of social media and contract cheating website use on the perception of academic integrity standards
Get PDFThis work sought to address gaps in the literature regarding perceived student acceptance of
certain types of cheating in higher education and the potential relationships to social media use
and the digital academic services, called contract cheating websites (Rowland et al., 2018) or
study helper websites (Harrison et al., 2021). In detail, the core of the study was the analysis of
social media and contract cheating website use and how it related to judgments of cheating
strategies by current and past postsecondary students. Through an online survey, participants (n
= 47) were asked to indicate demographic features; report the time spent on specific social media
sites and contract cheating websites (Chegg, Course Hero, and Quizlet); and indicate their
judgments of seven academic dilemma scenarios depicting cheating. Spearman correlations
revealed a moderate relationship between the time spent on social media and contract cheating
websites (rs = .438, p = .003). Although no links emerged between dilemma judgments and
social media in the overall sample, when separated into groups, contract cheating website users
(n = 17) indicated greater time spent on social media than non-users, t(42) = 2.847, p = .003,
along with correlations to certain cheating scenario and strategy judgments. These findings
highlight the need to investigate the underlying connections students may have to social media,
contract cheating services, and their perceptions of academic integrity to inform remedial
strategies for cheating in higher education
Experimental investigations on the effects of grid-screen, sand bed, and nozzle orientation on the dynamics of bubble plumes
Get PDFA bubble plume is defined as a column of air that flows through a liquid ambient due to the density difference between air and the ambient liquid. Bubble plumes have been utilized in wastewater treatment and oxygen transfer in civil and environmental engineering projects. Based on the injection pressure of air flow, bubble plumes can be converted to jet plumes or bubbly jets. A bubble plume is generated by the injected pressurized air/gas, and a bubbly jet is generated by injection of gas-liquid mixture in the ambient. In addition, bubble plumes can be generated by injecting air through a nozzle, airborne stone, or a group of diffusers into the ambient water. Bubble plumes are classified as two-phase air-liquid flow in which the ambient hydrodynamics and initial conditions dictate the motion of air bubbles and their sizes. Bubble plumes are extensively used in civil, environmental, and chemical engineering fields in many different industrial applications (Beutel et al., 2008). In recent years, there has been an increasing interest in using bubble plumes for mixing or aeration in lakes to improve water quality by adding oxygen. [...
Facial emotion recognition in women with symptoms of polycystic ovary syndrome
Get PDFPrior research suggests that hormones, notably androgens, influence facial emotion recognition
(FER). Most women with Polycystic Ovary Syndrome (PCOS) have elevated androgen levels
and related androgenic symptoms, yet no study has directly explored the relationship between
PCOS symptoms and FER. This thesis addressed this gap by investigating FER and self-reported
PCOS symptoms. During the FER task, men and women identified emotions (anger, disgust,
happiness, sadness or neutral) in images of emotional facial expressions. Both overall FER and
accuracy recognizing each individual emotion were examined. PCOS symptom severity was
assessed in women via self-report measures, including the Polycystic Ovary Syndrome
Questionnaire (PCOSQ). Consistent with previous research, women were more accurate than
men on FER. Additionally, women with provisional PCOS diagnoses were significantly less
accurate at overall facial emotion recognition than women without provisional PCOS diagnoses,
but this effect was driven by less accurate fear recognition. There was also a significant negative
correlation between FER performance for fear and PCOS symptom severity (e.g., Hair Severity).
A significant linear trend emerged for overall facial emotion recognition, revealing men as the
least accurate, followed by women with provisional PCOS, and women without PCOS. These
findings are consistent with the theory that androgens affect emotion recognition and suggest
implications for PCOS symptoms on women's emotional well-being. The results may partly
explain higher rates of mood disorders in women with PCOS and allow women with PCOS and
healthcare providers to better understand the effects of PCOS
Identifying and addressing roundabout accessibility issues confronting persons with vision loss in Canada: a pilot study
Get PDFMunicipalities and Transportation Agencies in Canada are building more roundabout
intersections to promote efficient and safe movement of traffic for their low carbon
footprint, low lifetime maintenance cost, and better safety performance thereby reducing
collision frequency and severity, among other benefits. The main disadvantage is that
Persons with Vision Loss (PWVL) feel unsafe when crossing the street on roundabouts.
One of the objectives of this research project is to identify the concerns and challenges
experienced by PWVL on roundabouts in Canada through a workshop and opinion
surveys involving participants scattered across the country. Another objective is to
conduct a field study assessing if the installation of sound strips on the road could help
PWVL when deciding to cross the streets on the roundabout in Thunder Bay. To achieve
these objectives the research team collaborated with the City of Thunder Bay, the staff,
and clients of the Canadian National Institute for the Blind (CNIB) to plan and facilitate
various events. It should be mentioned that 3D models of roundabout were used in
training and to illustrate points relevant to roundabout accessibility when discussing with
PWVL and other stakeholders. [...
Neural synergy in compact biomedical IoT devices: spintronic pathways for MEG-EEG integration and portability
Get PDFThe human brain, a marvel of nature, consists of intricate neural networks that have
fascinated and perplexed the scientific community for generations. As scientists and researchers globally endeavour to unravel the mysteries of bioelectrical activities that form
the basis of our cognitive functions and experiences, our research emerges at the nexus
of biology and cutting-edge technology. Specifically, we spotlight the remarkable capabilities of magnetoencephalography (MEG) and electroencephalography (EEG). These potent
neuroimaging tools, celebrated for their unparalleled spatial and temporal precision, are
synergistically combined in our study. We aim to map MEG innovatively signals onto
their EEG replicas, employing avant-garde spintronic devices, with a particular emphasis
on Magnetic Tunnel Junctions (MTJ). [...
UAVs employment in the next generation wireless communication systems
Get PDFNew network architectures of communication systems are required to support
and connect the next generation of wireless networks. This thesis focuses on unmanned aerial
vehicles (UAVs) as integral components of future wireless networks. Specifically, this
work addresses the optimization problem of association between the wireless access points
(WAPs) and UAVs, aiming to maximize the total weighted sum rate. This optimization problem is subjected to fulfilling quality of service (QoS), number of links, available
bandwidth, fairness, and coverage constraints. To address this challenge, a centralized
algorithm with reduced complexity is proposed for solving the association problem. The
results demonstrate that this algorithm’s solution offers excellent performance compared
to suboptimal alternatives and approach the exhaustive search technique while significantly reducing computational complexity