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A Place in Between. A study of the role emotions play in designing an architecture for teenagers.
No full textThere is a growing recognition that the atmosphere of spaces can
influence well-being, and significantly affect one’s emotional response to them. A welcoming atmosphere, for instance, can evoke feelings of comfort, safety, and, inclusion. However, understanding how users respond to architectural spaces, whether welcoming or un-welcome, remains a challenge. This thesis will begin to explore these challenges specifically for the user group consisting of teenagers.
This thesis is being driven by the following questions; How can spaces for
adolescents be created that support their emotional health and well-being while aiding them in their developmental journey? Can these spaces be adapted to meet the diverse needs of this demographic without forcing a one-size-fits-all approach?
It also raises the question, is it truly necessary to design such spaces? The aim for architecture is often to create environments that are inclusive for all. Yet, there can be an implicit expectation that every space should meet the needs of every unique demographic - a goal that, in reality, can be nearly impossible to achieve.
Adaptability, defined as, the capacity to be modified for a new use or purpose, is key to addressing this issue. It also prompts the query: how can existing spaces be transformed to prioritize and cater specifically to the teenage population? The design proposal outlines a series of opportunities as architectural spaces, providing guidelines to better understand this demographic’s needs and to design environments that effectively meet them.
By exploring how architectural spaces can better accommodate teenagers, the thesis begins recognizing their needs, acknowledging their role within the community, and fostering their personal and social development. Emphasizing the importance of adaptable and inclusive design, it proposes environments that actively support adolescent well-being
Optimal Sensor Protection and Measurement Corruption Detection in Safety-Critical Systems
No full textThis thesis addresses the detection and mitigation of sensor faults in safety-critical systems through secure estimation techniques. Sensor faults, whether accidental or adversarial, pose significant risks in autonomous vehicles, aviation, robotics, and other domains heavily reliant on accurate sensor data for safe operation. Traditional fault tolerance methods typically depend on hardware redundancy or ad-hoc designs for specific systems, approaches that can be prohibitively costly, or simplified assumptions about fault conditions that may not hold in practice. Recent advances in secure estimation provide a general framework with provable guarantees against sensor faults; however, their central requirement—sparse observability—is a worst-case scenario analysis, limiting their applicability in practical systems.
To address this limitation, this thesis introduces the concept of sensor protection, explicitly modeling selected sensors as immune to faults. This serves as an initial step toward capturing the practical scenario where some sensors are more fault-tolerant than others.
Although prior studies have implicitly assumed sensor protection by restricting potential fault locations, explicit modeling of sensor protection and its theoretical implications for fault tolerance have not been formally explored. This thesis extends the sparse observability framework to include protected sensors, broadening the applicability of secure estimation's theoretical guarantees. Additionally, a metric termed the safety factor is introduced to quantify a system's resilience to sensor faults, enabling targeted enhancements in robustness under practical resource constraints.
Further, this thesis adapts secure state-reconstruction methods to develop a robust fault detection algorithm suitable for nonlinear systems through linearization. We validate our methods extensively through simulation studies, retrospective analysis of a real-world autonomous vehicle racing incident, and practical implementation on a skid-steer robot. Results demonstrate significant improvements in real-time fault detection and operational safety under diverse fault conditions.
Overall, this work bridges theoretical advances in secure estimation with real-world deployment considerations, providing a structured methodology to enhance the reliability and safety of autonomous systems
Canadian Construction Automation and Robotics Roadmap
No full textThe contents of this report are the views of the authors and project team and do not necessarily reflect the views, positions or policies of the National Research Council of Canada or the Government of Canada.
© 2025 National Research Council and the University of Waterloo. All rights reserved. This report may not be reproduced, distributed or transmitted in any form or by any means, including photocopying, recording or other electronic or mechanical methods, without the prior written permission of the copyright holders, except in the case of brief quotations used for academic, research or review purpose with appropriate citation.Automation and robotics play a key role in construction productivity gains. A construction automation and robotics R&D roadmap to achieve such gains in Canada is presented in this report. Developed through workshops, practice and literature reviews, analysis, and synthesis, it includes an overall framework for how key Canadian stakeholders may participate in a technology pipeline that creates construction productivity gains through application of automation and robotics. Key knowledge and implementation gaps from the perspective of the construction industry are identified, as well as impediments to implementation of automation and robotics in construction. Suggestions are made for means by which such impediments can be overcome, and recommendations are made for implementation of a construction automation and robotics R&D program that will expedite deployment of solutions at scale.National Research Council Canada, Contract No. 1021275
High-Dimensional Scaling Limits of Online Stochastic Gradient Descent in Single-Index Models
No full textWe analyze the scaling limits of stochastic gradient descent (SGD) with a constant step size in the high-dimensional regime in single-index models. Specifically, we prove limit theorems for the trajectories of finite-dimensional summary statistics of SGD as the dimension tends to infinity. These scaling limits enable the analysis of both ballistic dynamics, described by a system of ordinary differential equations (ODEs), and diffusive dynamics, captured by a system of stochastic differential equations (SDEs). Additionally, we analyze a critical step-size scaling regime where, below this threshold, the effective ballistic dynamics align with the gradient flow of the population loss. In contrast, a new diffusive correction term appears at the threshold due to fluctuations around the fixed points. Furthermore, we discuss nearly sharp thresholds for the number of samples required for consistent estimation, which depend solely on an intrinsic property of the activation function known as the information exponent. Our main contribution is demonstrating that if a single-index model has an information exponent greater than two, the deterministic scaling limit, corresponding to the ballistic phase, or so-called dynamical mean-field theory in statistical physics, fails to achieve consistent estimation in high-dimensional inference problems. This shows the necessity of diffusive correction terms to accurately describe the dynamics of online SGD in single-index models via SDEs such as an Ornstein-Uhlenbeck process
Structured Wavefunctions for Precision Quantum Metrology
No full textIn this thesis, several projects from biomedical optics measurements of the retina to precision gravimetric designs with neutron interferometers are presented, united by the common theme of applied quantum information techniques to develop next-generation precision metrological instruments. In particular, we introduce theoretical tools for analyzing neutron optical experiments and highlight parallels between neutron and light optics. These tools are applied to a new neutron prism design, demonstrating significantly higher transmission than traditional designs. Designs for devices applying these techniques, including a neutron Fresnel prism, spectrum analyzer, and spin collimator, are discussed. Potential advantages in neutron flux and spectrum resolution are quantified for these designs. The isometry between neutron spin and the polarization of light is exploited to validate the neutron spin collimator experimentally. Applications of structured states of light and experiments applying spin-orbit states to create patterns in the human visual system are described. Results demonstrate an increase in the perceived extent of these patterns, from 3° for Haidinger's Brush to 10° for a spin-orbit state. Work demonstrating a new method of generating a lattice of spin-orbit states in light is applied to neutron optics. Throughout the preceding experiments, methods of modeling neutron optics experiments with light and a semi-classical path-integral approximation have been developed. These methods are then applied to design an experiment that measures the gravitational constant using a neutron interferometer. A three-phase grating moiré interferometer (3-PGMI) design is first tested with infrared light. The deflection caused by a wafer sample is measured with the 3-PGMI and found to match direct measurements. The path-integral model is then applied to determine the uncertainty in the gravitational constant that can be achieved with a near-term measurement with a neutron 3-PGMI. An experiment to measure the gravitational constant is described, with an uncertainty budget, resulting in a measurement to 150 ppm. Potential corrections to previous experiments measuring the gravitational constant, due to lunar gravitational forces are quantified. Future applications of the tools and techniques described in this thesis are then discussed
Reverse Logistics Network Design for Additive Remanufacturing
No full textThe current push for businesses to adopt sustainable supply chain practices contributes to a circular economy, a systems-focused approach designed to allow resources to be used and reused for as long as possible. The Canadian Net-Zero Emissions Accountability Act and the 2030 Emissions Reduction Plan developed by the Canadian federal government aim to regulate the environmental footprint by reducing greenhouse gas (GHG) emissions. Some of these goals can be achieved by designing reverse logistics networks. Reverse logistics is the design of a network for the purpose of collecting end-of-life/end-of-use products and reusing, repairing, refurbishing, remanufacturing, and/or recycling.
This thesis proposes four models to design a reverse logistics network: deterministic, multi-period, stochastic, and a game theory model. The models are formulated as bi-objective mixed-integer linear programs. The design of the network is optimized with respect to economic and environmental objectives. The balancing of costs and environmental objectives during the design of the reverse logistics network provides the decision-maker with additional information on how environmental goals can be met. The models aim to determine the optimal locations for remanufacturing facilities and the optimal flow of parts to and from these facilities. The bi-objective models are solved using the weighted sum method, which allows for Pareto-optimal solutions to be analyzed. The models are solved using Gurobi in Python.
Deterministic, stochastic, and game theory models are applied to a case study for the remanufacturing of front lower control arms in the automotive industry in Ontario, Canada. The stochastic model is motivated by the uncertainty in the supply of end-of-life vehicles. The stochastic model is solved using the deterministic equivalent. The game theory model complements the aforementioned approach. It facilitates the triangulation of the results.
The models select the optimal locations for the remanufacturing facilities. Significantly, all three models applied to the case study produce similar results. The quantitative results demonstrate that the optimal solution based on the case study data is when multiple facilities are located, one facility should be opened in Ottawa and at least one other in the GTA. When only one facility is located, it should be placed in the GTA (either Mississauga or Brampton). Overall, the results reveal that small investments can lead to significant reductions in greenhouse emissions released during transportation.
The results can be scaled to design a reverse logistics network for Canada and inform environmental policies. The results and findings of this study may be used to inform policies on the reduction of transportation emissions. The contributions that the thesis makes to the field are: (i) it incorporates greenhouse gas emissions into the models; (ii) it allows decision-makers to compare the results of the three models (deterministic, stochastic, and game theory) applied to the case study; and (iii) it applies the models to real-world data
Quantum Algorithms for PDEs via Summation-by-Parts Discretisations
No full textPartial differential equations (PDEs) underpin the mathematical description of physical phenomena across science and engineering. High-order discretisation techniques, such as those based on the Summation-by-Parts (SBP) framework, provide accurate and energy-stable numerical schemes that preserve conservation and stability properties of the continuous equations. These discretisations yield large, linear systems that have significant structure, whose solution constitutes the computational bottleneck of many scientific simulations. Quantum systems can represent exponentially large state spaces using only a polynomial number of qubits. By exploiting this representational capacity, quantum algorithms can achieve substantial, and in some cases exponential, speedups for certain classes of computational problems. However, the practical application of quantum algorithms to PDEs is challenging as a result of the difficulty of efficiently representing the discrete operators as unitary transformations suitable for quantum computation.
This thesis establishes a first step and a significant step toward a unified framework linking high-order SBP discretisations with quantum algorithms based on polynomial spectral transformations. Using Quantum Singular Value Transformation (QSVT), we show how the matrix exponential exp(AT), governing time evolution in semi-discrete PDE systems, can be efficiently implemented as a quantum circuit. A key contribution is the development of systematically constructible and ancilla-efficient block-encodings for structured matrices, including those arising from high-order SBP discretisations of PDEs. These constructions exploit the tensor-product and sparsity structure of the underlying differential operators to enable automated coherent circuit synthesis with polylogarithmic scaling in system size. The resulting framework bridges classical numerical methods and quantum algorithm design by embedding stable, high-order discretisation operators into the coherent quantum model.
The methods are demonstrated on the linear advection equation by block-encoding the SBP semi-discrete operator and applying QSVT to realise its time evolution. This work serves as a blueprint for applying QSVT-based quantum algorithms to high-order discretisations of general linear PDEs
Decolonizing Disability: access without erasure
No full textThis thesis rethinks disability in the Global South by turning to Nigerian open-air markets, rather than institutional settings as primary sites of inquiry. More than points of exchange, these markets are cultural and civic arenas where economic activity intersects with social connection, mutual care, and collective identity. Marketplaces often function as “third places,” sustaining relationships, preserving communal memory, and hosting the negotiation of public life alongside commerce. Within this context, disability is framed not as a fixed biological deficit but as a condition shaped by environments, social structures, and cultural narratives. Drawing on critical disability studies, African epistemologies, and the concept of relational access, the project positions design as a continual negotiation between bodies, space, and practices of care, challenging functionalist approaches that reduce access to technical compliance.
A central critique advanced in this research is the co-option of accessibility language to legitimize exclusionary development. In postcolonial African cities, modernization projects often promise accessible infrastructure while simultaneously displacing those most reliant on markets for survival. Under the banner of “ultra-modern” shopping complexes, elderly traders, people with impairments, and low-income groups are frequently priced out, excluded from decision-making, and stripped of long-standing spatial and economic networks. In such cases, access becomes a rhetorical tool for privatization and displacement rather than a pathway to justice. This thesis argues that genuine access must go beyond token infrastructural features to address the deeper social, economic, and political systems that sustain participation.
Methodologically, the study combines critical literature with graphical anthropology, using mapping and diagramming to interpret the spatial conditions of Nigerian markets. This approach, informed by Jos Boys’s “Having a Body” framework, highlights how non-normative bodies engage space, revealing barriers such as uneven ground, sensory overload, or disorientation, alongside supports like shared seating, mutual caregiving, and assistance from load carriers. Through this iterative method, the research develops strategies grounded in lived realities rather than abstract standards, emphasizing collective arrangements that sustain participation. The design proposal focuses on Jos Main Market, a once-celebrated hub now in disrepair after arson and neglect. The intervention introduces a spine that organizes utilities and circulation while embedding care nodes for prayer, rest, sanitation, and basic medical support. A market workshop provides space for repair, fabrication, and low-cost assistive devices, affirming resourcefulness and local skill as vital forms of access. At its center, a market plaza serves as a commons, enhancing visibility and offering social services such as collective childcare, community kitchens, thrift collectives, and meeting areas. Together, these spaces strengthen support networks and ensure vulnerable groups remain active within the civic life of the market.
Ultimately, the thesis positions open-air markets as sites that resist the misuse of accessibility rhetoric by grounding access in reciprocity and collective care. Rather than treating informality as disorder to be erased, it demonstrates how markets themselves model alternative approaches to spatial justice. By centering lived experience, this project advances a decolonial vision of disability design, one where access is relational, negotiated, and inseparable from economic survival and community life
Polymorphic Type Qualifiers
No full textType qualifiers offer a simple yet effective mechanism for extending existing type systems to deal with additional constraints or safety requirements. For example, the const qualifier is a popular mechanism for annotating existing types to signify that the value in question is read-only in addition. A variable of type const int is both an integer and also cannot be written to.
While type qualifiers themselves are well-studied, polymorphism over type qualifiers remains an area less well examined. This has led to a number of ill-desired outcomes. For one, many practical systems implementing type qualifiers in their type systems simply ignore their interaction with generic types. Other systems implement polymorphism with seemingly unique and ad-hoc rules for dealing with qualifiers.
In this thesis, we show that this does not need to be the case. We start by examining three well-known qualifier systems: systems for tracking immutability, function colour, and captured variables, and show that despite their differences that they share surprising common structure. We then give a design recipe, inspired by that structure, using the mathematical structure of free lattices for modelling polymorphism over type qualifiers, to give a framework for polymorphic type qualifiers. We then show that our design recipe precisely captures this structure by recasting those three existing systems in our framework for qualifier polymorphism by free lattices. Finally, we extend type qualifiers from ranging over lattices to type qualifiers ranging over Boolean algebras, which we then use to extend an existing effect system with effect exclusion to support subeffecting as well via subqualification and subtyping
Multisensory Immersion in Architectural Virtual Reality: Effects of Visual and Auditory Cues
No full textThe evolution of architectural representation has progressed
from traditional analog methods such as hand-drawing to contemporary
digital technologies like Virtual Reality (VR) which emerges as the
latest architectural representation in spatial visualization and client
communication. However, current implementations of architectural VR
heavily focus on visual presentation, potentially underutilizing the capacity
for comprehensive multisensory experiences that could significantly
enhance users to have comprehensive understanding and more
engagement within proposed space.
This paper investigates the role of spatial auditory effects in
enhancing architectural VR experiences and examines how multisensory
(particularly visual and auditory cues) design approaches can improve
user engagement and spatial communication effectively. Through a
comprehensive three-part methodology, this research addresses critical
gaps in current architectural VR representations which visual-only
approaches represent partial utilization of the contemporary potential of
technology.
In PART 1, through trend extrapolation from historical evolution,
‘what’s the next?’ was predicted that architects should utilize architectural
VR representation to prepare for emerging technological paradigms. The
analysis of various contemporary precedents in the architectural field
shows that current architectural VR implementations primarily focus
on providing better visualization and virtual experiences to clients and
stakeholders, while insufficient attention is on multisensory architectural
VR applications.
PART 2 introduces the cognitive foundation for sound integration in
architectural representation and explains the necessity of applying spatial
audio to architectural VR presentations for enhanced communication. This
part outlines specific acoustic properties such as attenuation, overlapping,
and diffraction and shows their potential applications in architectural
design visualization. This foundation demonstrates how these properties
can enhance the awareness of relationships in spatial hierarchy, active
zones, and connectivity.
PART 3 presents experimental validation through repeated measures
with 38 participants experiencing three conditions: PC-based non-VR,
visual-only VR, and both visual and auditory VR. The results demonstrate
progressive increases in participants’ voluntary engagement, with
multisensory VR achieving 198.1% improvement in play time compared to
traditional PC-based presentation.
These findings provide architects experiment results based on
numerical evidence and encourage them utilizing multisensory integration
as fundamental to effective VR representations rather than optional
enhancement. This research contributes to architectural practice by
providing measurable advantages of comprehensive sensory experience in
VR-based communication and spatial understanding