30921 research outputs found
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Energy modelling and analysis of vertical farming for vegetable production
No full textVertical farming has gained popularity in the last ten years as a potential solution to produce food
using minimal resources. A key challenge in vertical farming is intensive energy usage. Limited
research exists however on the energy consumption for vertical farming facilities in cold climate
conditions. An energy model was developed to estimate the energy consumption for growing
lettuce in a small pilot facility. To validate the model, two tests of butter head lettuce, loose leaf
lettuce, and kale were grown in the pilot facility. One test occurred from January – February 2024,
and the second was in September – October 2024. During the testing period energy usage for the
HVAC (heating, ventilation, and air conditioning) system, lighting, irrigation, and IoT sensor and
control were recorded and compared with model estimations. The results showed that the two
highest energy usages were from lighting and HVAC. Lighting accounted of 46 %– 75% of the
total energy consumption, whereas HVAC accounted for 22% - 52%. Overall, it took
approximately 29.6 kWh in the winter and 43.9 kWh in the fall to grow looseleaf lettuce for one
crop cycle. It was found that less energy was required to operate the SVF in the winter than in the
fall due to not requiring cooling during the winter season. The average energy consumption was
451.8 and 676.1 kWh per month for winter and fall, respectively. The energy consumption per m2
of floor area measured in this study (517.2 - 773 kWh/m2y) was generally lower than that in
different geographic regions reported in the literature (850–1150 kWh/m2y). The energy model
developed in this study performed well for calculating energy consumption by the lighting system
(LEDs) but it was less accurate for calculating heating requirements. Overall, the findings from this
study proved that vertical farming could be adapted successfully to cold climate regions.February 202
Designing a decentralized quantum-resistant notary scheme for blockchain interoperability with a dynamic trust model
No full textBlockchain interoperability is essential for enabling advanced functionalities in decentralized applications, particularly for secure and reliable interactions across disparate blockchain networks. The Notary scheme is a common approach to achieving interoperability; however, it faces significant challenges: vulnerability to quantum computing threats and the complexities of trust management in dynamic, adversarial environments. We investigate a decentralized, quantum-resistant interoperability framework designed to address these challenges through a novel protocol and trust model. The protocol integrates post-quantum cryptographic techniques, including ML-KEM for key distribution, ML-DSA for digital signatures, and AES-256 for message encryption, ensuring security and resilience against emerging quantum threats. Complementing this, we introduce a dynamic trust model that leverages Popoviciu’s inequality to manage and update reputation scores in real time, enhancing resilience against trust degradation and enabling recovery from malicious behavior and network fluctuations. Experimental evaluation shows that our proposed protocol achieves quantum resistance while maintaining performance comparable to traditional cryptographic approaches. Moreover, the novel trust model provides accurate and dynamic trust computation under varying network conditions, contributing to more robust and trustworthy interoperability.October 202
Investigating how homeopaths and chiropractors navigate patient requests for vaccination information in Ontario, Canada: a qualitative study
No full textBackground. Chiropractors and homeopaths are trusted sources of health information for many Canadians, including around vaccination. However, within Ontario, Canada, the College of Chiropractors of Ontario and the College of Homeopaths of Ontario regulations state that vaccines are not within their scope of practice and providers should not express views, treat, or advise patients with respect to vaccination. The aims of the present study were to: (1) describe the attitudes and beliefs regarding vaccination held among participating chiropractors and homeopaths; (2) identify the sources of information about vaccination they trust and use to guide their personal vaccination decisions; and (3) describe how they navigate patient requests for guidance on vaccine decision-making within the current regulatory landscape. Methods. Semi-structured interviews (N = 16) were conducted between February 2020-March 2021 and explored participants’ opinions on vaccination, sources of information they trust and recommend to their patients, and how they navigate vaccine conversations with patients. Results. Providers’ personal beliefs regarding vaccination were described as reinforced by social and professional networks, through their personal experiences, and in consultation with clients. Various strategies were used to support patients while abiding by regulations (e.g. referring patients to providers for whom vaccination is within their scope of practice); however, other strategies described (e.g., stating personal beliefs) could be interpreted as a breach of regulation. Conclusions. This research reinforces existing literature suggesting that patients using chiropractors and homeopaths have questions about vaccination and are looking for trusted information. Public health services should consider engaging with chiropractors and homeopaths to facilitate communication between patients and immunization providers
On the practical viability of competitive algorithms for the homing online traveling salesperson problem: empirical evaluation and practical recommendations
No full textThe Homing Online Traveling Salesperson Problem (H-OLTSP) models a dynamic routing scenario in which a server must respond to requests revealed over time while always returning to a fixed origin. Here, the server represents a moving agent, such as a robot or vehicle, that travels through the metric space to serve requests. Although competitive algorithms such as Plan At Home (PAH) and Greedily Traveling between Requests (GTR) have been proposed under competitive analysis, their behavior under practical conditions remains largely untested. Competitive analysis reflects worst-case performance but may not capture how these algorithms perform in realistic environments where response speed and solution efficiency are critical.
This thesis bridges that gap by empirically evaluating PAH and GTR through simulation. Each algorithm is implemented with multiple scheduling strategies and tested under controlled experimental settings that vary the number of requests and the distribution of their release times. The evaluation focuses on two core aspects: responsiveness, which reflects how quickly the server reacts to incoming requests, and efficiency, which reflects how effectively the algorithm solves each H-OLTSP instance.
The study compares GTR and PAH directly and evaluates how each performs when combined with different scheduling algorithms under varying conditions. The results provide practical insight into the trade-offs between response speed and instance-solving efficiency, revealing performance differences that are not visible through theoretical analysis alone. This work offers a grounded perspective on the real-world suitability of competitive online algorithms. It guides their application in dynamic routing applications that require timely decisions and low completion time.October 202
Eradicating violence against children: understanding the experiences of community activists and advocates in addressing child labor practices in Ghana
No full textThe persistent global nature of violence against children demands urgent attention. In Ghana, child labor significantly contributes to this violence, exposing children to hazardous conditions that undermine their safety, rights, and development. In response, community advocates play a crucial role in protecting children and challenging harmful practices. This study examined the experiences of these advocates, conceptualizing child labor as a form of violence and situating advocacy within the field of Peace and Conflict Studies (PACS). The study explored what can be learned from the lived experiences of advocates, how their efforts shape our understanding of child labor eradication, and what their work reveals about grassroots peacebuilding. A qualitative narrative research design was employed. Fieldwork was conducted in Ghana’s forest belt regions (Ashanti, Central, Western, and Western North), involving thirty community advocates selected through purposive and snowball sampling. Data were generated through semi-structured interviews and interpreted using thematic narrative analysis.
The findings revealed that personal histories of suffering, a strong sense of responsibility, passion for social change, and spiritual convictions drive these advocates. Their strategies include awareness-raising, community empowerment, and collaboration with stakeholders. However, they also face persistent challenges, including entrenched poverty, community resistance, lack of funding and support, duplication of efforts, and limited sustainability after NGO withdrawal. The results indicate that child labor advocacy in Ghana begins with the role of community advocates as witnesses to the everyday atrocities faced by children, positioning themselves as ethical agents confronting normalized violence. It further emerges as a form of activism centered on securing children’s right to education, where schooling is framed as both a protective right and a pathway to peace. This advocacy also constitutes a direct confrontation with material constraints and systemic resistance, as advocates navigate poverty, institutional neglect, and entrenched socio-cultural norms. Many advocates approach their work as a spiritual and moral calling, positioning themselves as missionary peacebuilders committed to justice and transformation. At the same time, they act as local implementers of global child protection frameworks, translating international policies into culturally meaningful community action. The study argues that these intersecting roles of the advocates emphasize that grassroots advocacy is not separate from, but embedded within, liberal peacebuilding paradigms, offering a nuanced model of peacebuilding in non-conflict yet structurally violent settings.Berdie and Irvin Cohen Scholarship in Peace and Conflict Studies
Faculty of Graduate Studies Research Completion ScholarshipOctober 202
Critical literacy stories untold: exploring students' identities in an out-of-school context
No full textThis dissertation explores how students construct, negotiate, and express their identities through storytelling-based literacy practices in an out-of-school learning context. Grounded in Critical Theory of Education, Critical Literacy, and Affect Theory, the study introduces the concept of Affective Liberation Literacy, a framework that integrates critique, emotion, and identity as co-constitutive forces in transformative learning. Drawing on practitioner inquiry and narrative inquiry, the research examines a five-week program titled Tell Your Story Academy, where students engaged in multimodal storytelling activities structured around the Tree of Life framework. Findings reveal that when literacy practices are rooted in relationality, embodied engagement, and student voice, young people develop a deeper sense of self, agency, and belonging. This study offers both a theoretical and practical contribution to identity-centered literacy education, urging educators to create learning environments that prioritize connection, critical reflection, and the affirmation of students’ lived experiences.October 202
Designing realistic and interactive avatars in virtual reality environment with embedded serious games: a farm for mental health using Indigenous healers and a museum tour for older adults with cognitive impairment
Get PDFThe utilization of avatars in virtual reality (VR) has emerged as a powerful tool for addressing psychological and cognitive disorders, offering unique opportunities to enhance therapeutic and rehabilitative interventions. This study focuses on the development of naturalistic avatars and their integration into two different VR environments with serious games designed to support mental health and cognitive engagement. The Oculus Rift headset was used to provide the immersive VR experience, while Unity’s animation state machine ensures smooth transitions and responsive interactions within the virtual environment.
Inspiring by the Indigenous culture, the first component of this study focuses on the development of a naturalistic avatar in a VR environment to represent an individual as a “healer” or a “therapist”. Leveraging VR and character creation software tools, an avatar was created based on the provided image of a current Indigenous healer, including intricate facial expressions, synchronized lip movements, and lifelike body gestures. The ultimate application is to utilize the naturalistic avatar of a healer for mental health treatments and replication of real-world therapeutic interactions. The developed avatar as a digital representation of an Indigenous healer was evaluated by 4 Indigenous individuals. The second component of this study extended the use of avatars into a virtual museum designed for cognitive stimulation amongst older adults experiencing memory challenges and/or loneliness. In this environment, a tutor avatar guides users through interactive museum exhibits, encouraging engagement, attention, and memory recall. The avatar was integrated into the Unity environment to enable user interaction, with various scenarios developed to assess engagement and cognitive performance.
These above-mentioned two projects establish a foundation for using avatar-guided VR experiences as innovative therapeutic and cognitive tools. They demonstrate the potential of naturalistic avatars not only for mental health treatment but also for promoting cognitive well-being and social connection among diverse populations.February 202
Evaluating the performance of five large language models in answering Delphi consensus questions relating to patellar instability and medial patellofemoral ligament reconstruction
Get PDFPurpose: Artificial intelligence (AI) has become incredibly popular over the past several years, with large language models (LLMs) offering the possibility of revolutionizing the way healthcare information is shared with patients. However, to prevent the spread of misinformation, analyzing the accuracy of answers from these LLMs is essential. This study will aim to assess the accuracy of five freely accessible chatbots by specifically evaluating their responses to questions about patellofemoral instability (PFI). The secondary objective will be to compare the different chatbots, to distinguish which LLM offers the most accurate set of responses.
Methods: Ten questions were selected from a previously published international Delphi Consensus study pertaining to patellar instability, and posed to ChatGPT4o, Perplexity AI, Bing CoPilot, Claude2, and Google Gemini. Responses were assessed for accuracy using the validated Mika score by eight Orthopedic surgeons who have completed fellowship training in sports-medicine. Median responses amongst the eight reviewers for each question were compared using the Kruskal-Wallis and Dunn’s post-hoc tests. Percentages of each Mika score distribution were compared using Pearson’s chi-square test. P-values less than or equal to 0.05 were considered significant. The Gwet’s AC2 coefficient was calculated to assess for inter-rater agreement, corrected for chance and employing quadratic weights.
Results: ChatGPT4o and Claude2 had the highest percentage of reviews (38/80, 47.5%) considered to be an “excellent response not requiring classification”, or a Mika score of 1. Google Gemini had the highest percentage of reviews (17/80, 21.3%) considered to be “unsatisfactory requiring substantial clarification”, or a Mika score of 4 (p AC2 ≥ 0.60) for ChatGPT, Perplexity AI, Bing CoPilot, and Claude2, while there was no agreement for Google Gemini (AC2 < 0).
Conclusion: Current free access LLMs (ChatGPT4o, Perplexity AI, Bing CoPilot, and Claude2) predominantly provide satisfactory responses requiring minimal clarification to standardized questions relating to patellar instability. Google Gemini statistically underperformed in accuracy relative to the other four LLMs, with most answers requiring moderate clarification. Furthermore, inter-rater agreement was moderate for all LLMs apart from Google Gemini, which had no agreement. These findings advocate for the utility of existing LLMs in serving as an adjunct to physicians and surgeons in providing patients information pertaining to patellar instability.
Level of evidence:
Incorporating accurate sub-cell antenna models into microwave imaging algorithms with a finite element thin wire antenna model
Get PDFThis thesis presents a procedure to incorporate accurate sub-cell antenna models into existing microwave imaging algorithms.
The incorporation of the sub-cell antenna model greatly reduces modelling error between experimental systems and their associated numerical counterparts.
The microwave imaging pipeline, including the associated numerical model, experimental data calibration, and proposed objective function in the microwave imaging procedure, have all been updated to exploit the use of an antenna model.
A time-harmonic finite element sub-cell thin wire antenna model was developed to model a quasi-resonant flat faceted metallic imaging chamber that was excited with thin wire antennas.
Experimentally measured data, and numerical experiments, demonstrate that the implemented thin wire antenna model is valid for both straight and curved antenna geometries.
The proposed imaging procedure was tested in the aforementioned faceted chamber imaging system and compared with a point source antenna model.
Image reconstruction quality metrics across a wide frequency band demonstrate that the proposed imaging algorithm incorporating an antenna model greatly improves imaging performance of dielectric targets.
Additionally, the newly proposed calibration technique used with the imaging algorithm has improved performance compared to the previously used technique.
The proposed imaging algorithm was also synthetically evaluated with magnetic targets, and was found to have comparable imaging performance to an equivalent dielectric target.February 202
A critical ethnography of gender (in)equality, NGO practices and neoliberal entanglements in Ghana
Get PDFInternational and national non-governmental organizations (NGOs) have become part of a complex combination of factors that add nuance to processes of exploitation and inequality in society. This thesis examines Ghanaian NGO ‘development’ discourses that prioritize “women’s empowerment” and scruitinizes the ways in which “an exploitable subject” is generated for, and maintained, by NGOs’ as they formulate and implement projects. To accomplish this, I investigate one international ‘development’ NGO in Ghana (Grameen Foundation) and its local implementing partners, and a major Ghanaian national advocacy NGO called Abantu for Development. The projects of these two organizations aim to “empower” women and address gender inequality, and are funded by donors in the United States and Western Europe. I draw on the activities of these two organizations to explore three key issues in this study: 1) the operational workings of NGOs in Ghana; 2) the experiences of women ‘beneficiaries’ of projects led by international NGOs; and 3) the forms of exploitations and exclusions that occur as NGOs implement projects. In exploring these issues, I adopt a multi-directional ethnographic approach (“up” the workings of the NGOs and interviews with women ‘beneficiaries’) to reveal the specific ways that “exploitable subjects,” created by the dispossessions of capitalist and neoliberalist policies, are sought out for NGO projects, and further exploited through NGO activities. Using this approach, I construct ethnographies by talking to people on the job, by participating in the NGOs’ activities, and by documenting the experiences of the women ‘beneficiaries.’ My findings indicate that while some women benefit from NGO projects, international gender equality projects in Ghana exclude local women in deliberations about their needs, and end up – for the most part – exacerbating inequalities experienced by so-called ‘beneficiaries' and further deepening local women’s ‘exploitable subject’ positions. This study contributes to existing literature on African feminism by critically analyzing the often-unexamined implementations and impacts of gender equality projects led by international organizations and their local counterparts. Through this, I ultimately reveal the specific discourses and practices that combine in NGOing to structure ‘exploitable subject’ positions for rural Ghanian women today.University of Manitoba Graduate Fellowship (UMGF)February 202