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Development of a Safety Maturity Framework for Proactive Risk Management in Construction
No full textThe construction industry consistently ranks among the most hazardous sectors worldwide, with high rates of injuries and fatalities that underscore the urgent need for effective safety management practices. While Safety Management Systems (SMS) are widely adopted to mitigate risks, these systems often rely heavily on lagging indicators providing limited insight into potential future risks. In contrast, leading indicators offer proactive signals that can forecast and prevent safety incidents. However, the adoption and integration of safety leading indicators into construction practices remain fragmented, with limited understanding of their definitions, interrelationships, and practical effectiveness. This research addresses this critical gap by proposing a comprehensive, data-driven framework for advancing proactive safety management in construction. The primary objective is to develop and validate a systematic approach that integrates leading and lagging indicators through a causation model and leverages their dynamic interrelationships within a safety maturity framework. By doing so, the study supports construction organizations in transitioning from reactive compliance-based systems to proactive safety cultures.
The research follows a multi-phase methodology. First, a systematic literature review was conducted to synthesize existing knowledge on safety leading indicators. This review identified significant variability in definitions and usage patterns, but a clear trend toward greater recognition of their predictive value. It also highlighted a lack of integration between leading indicators and broader safety performance models, which limits their operational utility. The review extracted and categorized 24 leading indicators and analyzed their trends, roles, and potential influence on safety outcomes. Building on these findings, a causation model is developed using Fuzzy Cognitive Mapping (FCM) to visualize and quantify the complex, non-linear relationships among key safety indicators. The FCM approach allows for the inclusion of expert judgment and uncertainty, capturing how factors such as safety training, hazard identification, management commitment, and worker engagement dynamically interact to influence safety performance. Simulation of “what-if” scenarios further demonstrated how interventions in certain indicators could produce cascading effects across the system, enabling targeted and effective risk mitigation strategies. The insights from the causation model laid the foundation for a Safety Maturity Framework (SMF) tailored for construction organizations. The SMF assesses the maturity level of safety practices based on the implementation, effectiveness, and interdependence of leading indicators. It provides a structured roadmap to guide organizations through progressive stages of safety capability, ranging from basic compliance to strategic, integrated safety leadership. The framework was validated through expert panels and comparative analysis with existing models, confirming its practical applicability and enhanced predictive power.
This integrated approach grounded in systems thinking, expert-driven modeling, and empirical validation, offers significant contributions to both academic knowledge and industry practice. It redefines the role of safety indicators from static metrics to dynamic components of a responsive safety management system. Furthermore, by aligning safety evaluation with project planning and organizational behavior, the proposed framework enables a more holistic understanding of construction safety performance. Ultimately, this research aims to improve the health, well-being, and productivity of construction workers by empowering organizations to anticipate and prevent incidents before they occur. The integration of predictive models, cognitive mapping, and maturity assessment tools provides the construction industry with a robust, scalable, and evidence-based pathway for advancing safety culture and performance. In doing so, the study contributes to the broader evolution of safety science, promoting proactive risk management strategies that are adaptable to the complex and ever-changing nature of construction environments
High-Speed Internet and Energy for All: Who Are the 'All,' and How Do We Reach Them?
No full textAs the 2030 deadline for Sustainable Development Goals 7 and 9 (SDG 7 & 9) approaches, achieving universal access to modern energy and digital infrastructure remains a critical challenge, particularly in sub-Saharan Africa. In 2021, 59.5% of Nigerian households lacked electricity, with only 45% having internet access. Similarly, 54.2% of Ethiopian households had no electricity, and just 17% had internet access. While infrastructure deficits are well-documented, the drivers of these disparities—and the link between high-speed internet access (2G, 3G, 4G) and energy poverty (lack of clean, reliable, and affordable energy)—remain poorly understood by researchers, policy makers, and the public. Does increased internet access raise household energy demand, worsening affordability issues? Or can digital connectivity help alleviate energy poverty by enabling employment, education, financial inclusion, and awareness of energy-efficient technologies? Using Ethiopia and Nigeria as case studies, this research will identify regions with the most severe access gaps and assess whether digital connectivity can serve as a pathway to alleviating energy poverty. We will develop a framework to analyse how, when, and why high-speed internet influences energy poverty, focusing on its effects on household energy demand, income generation, and access to information. We will also examine how these dynamics vary across demographic factors such as gender, income, ethnicity, and migration status
Fault Tolerant Strategies for Modular Multilevel Converter Systems
No full textThe integration of renewable energy sources (RES) such as wind, solar photovoltaic, and fuel cells has accelerated significantly in recent years. Power electronics has emerged as a core enabler for the efficient and flexible integration of RES into the grid. Among the available power converter technologies, modular multilevel converters (MMCs) have become a leading solution due to their modular and scalable architecture, and are increasingly deployed in a wide range of medium- to high-voltage applications. MMC-based medium-voltage DC (MVDC) and high-voltage DC (HVDC) systems must meet stringent requirements for reliability and availability. The development of robust fault detection and localization (FDL) and fault-tolerant control (FTC) strategies is essential to ensure the safe and continuous operation of MMCs in both MVDC and HVDC applications.
This thesis investigates reliability challenges and fault-handling strategies for MMC-based systems in MVDC and HVDC applications. The study focuses on two types of faults: 1) component-level switch open-circuit faults (OCFs) within submodules (SMs) in the phase leg of MMCs, and 2) a system-level fault involving the complete loss of MMC phase leg(s). The proposed FDL and FT strategies are validated through both experimental setups and real-time simulation environments.
Firstly, a new FDL scheme based on signal synthesis is proposed to detect and localize SM OCFs simultaneously. This method introduces two signature signals, avoiding the need to synthesize all individual capacitor-voltage waveforms, which keeps the computation burden low and constant as the number of SMs per arm increases. The approach demonstrates short FDL time, robustness against load change, and can handle multiple simultaneous faults, verified in simulation and experiment.
Secondly, a model-informed, estimation-based FDL scheme for SM OCFs is developed, proposing a simplified model and disturbance observer (DOB) applied to only one signature signal for the purpose of FDL. This reduces computation and implementation complexity and achieves accurate, robust detection under load change and measurement noise, as demonstrated in experimental results.
Thirdly, real-time simulation tests further show that the first proposed scheme scales effectively to practical MMC design with high SM counts (100 SMs per arm), maintaining accurate and fast FDL performance. A control hardware-in-the-loop (CHIL) platform is also developed, integrating an RTDS, an Imperix Boombox (BBox) controller, and a high-speed digital communication link. The effectiveness of the setup is verified, and transmission delays within the CHIL loop are analyzed to confirm feasibility for real-time control verification.
Finally, a FT operation and control strategy is developed to address the complete failure (loss) of phase legs within multiport MMCs in bipolar MVDC systems. By implementing the proposed FT strategy, the bipolar system is able to maintain the pole-to-pole voltage under both single-phase leg failures (SPF) or even double-phase leg failures (DPF) occurring on different electrical phases across two different MMCs. Despite unbalanced AC terminal three-phase currents injected by each MMC during fault conditions, the multiport MMC system can still generate or absorb balanced three-phase grid currents. Such operational resiliency is not possible to achieve with conventional MMC-based bipolar systems. A ripple analysis and corresponding mitigation strategy are conducted to ensure that the DC port currents remain effectively ripple-free. The effectiveness of the proposed strategy is validated using the previously developed CHIL test platform, where signal exchange between RTDS and Imperix BBox is facilitated via an Aurora digital high-speed communication link
Environmental Sustainability and Sport
No full textResearch recognized the lack of transparency and public reporting of environmental initiatives among professional sport organizations, and it remains relatively unknown as to the explicit, strategic ways organizations communicate and promote their environmental sustainability (ES) activities. This dissertation aims to investigate this topic further by studying how organizations communicate their ES initiatives. To do so, three separate case studies were conducted. In the second chapter, using a content analysis of text from Candidature Files, rhetorical theory was employed as a lens to study the ways in which Olympic bid committees employ rhetoric in their candidature files vis-à-vis their ES plans. The chapter revealed one distinct rhetorical appeal emerged more than the others that underscored the value of highlighting credibility in ES contexts. In the third chapter, a content analysis of public facing news sources, and the lens of rhetorical theory were used to explore how partners of arenas with naming rights agreements in the emerging ES category articulate such partnerships. This chapter found the partners of ES naming rights agreements use various types of rhetoric to describe the decision to coalesce around ES. In the fourth chapter, a cultural entrepreneurship lens and a narrative analysis of text from public facing documents were employed to better understand the ways in which professional sport arenas with third-party green building certification employ narratives to communicate their venue’s broad ES practices. It was found that organizations that do receive green building certification are almost always going to publicly communicate it as it may provide an opportunity to be perceived as optimally distinct. The insights from these three chapters may bring forward implications for the broader sport sector as an effective climate change and environmental sustainability communicator, while also bringing concurrent organizational and market advantages
Assessing the Transitional Impact of Adverse Public Events and Associated Mental Health Consequences
No full textMajor public events like the COVID-19 pandemic and natural disasters profoundly impact the lives of large groups of people. These events often produce economic hardship, social disruption, and psychological distress that can be long-lasting. Moreover, these events indicate significant changes in people's lives. To elaborate, these calamitous public events can indicate transition– a synchronized, fundamental change in the fabric-of-daily life, in what people do, where they do it, and with whom. Therefore, the aim of the current thesis was to investigate: (a) the nature and extent of the transition caused by COVID-19 pandemic and natural disasters, (b) the impact of the pandemic- or disaster-specific transition, (c) the effect of the pandemic-or-disaster on individuals’ mental-health, and (d) the relationship between the effect of pandemic-or-disaster brought transition and mental-health. This was accomplished in four studies. Chapter 1 provides a general introduction of the potential transitional properties of the pandemic and natural disaster, and how this pandemic- or disaster-related transition can affect the lives and mental-health of individuals. Here, an overview of the research findings related to transition, pandemic, disaster, and mental-health was provided. For simplicity, Chapter 1 is split into two-parts. The first-part discusses the COVID-19 pandemic, and the second-part discusses natural disasters. Chapter 2 (Study-1) reports the results of a cross-sectional survey of Canada-US adults conducted between March 24 and 30, 2020, at the COVID-19 pandemic onset. This study examined the immediate effect of the pandemic-brought transition, pandemic’s impact on mental-health, and the degree to which the two were related. The results indicated that at early stage, the pandemic produced: only moderate material and psychological change, and mild-to-moderate distress; job-loss people experienced more change and more distress than those who did not; material and psychological change were associated with depression and stress while anxiety was associated with only psychological change. Chapter 3 (Study-2) describes the findings of a longitudinal survey of Canada-US and Turkish adults compared across four time-points (March 2020 – April 2022). Study-2 examined the long-term transitional effects brought by the COVID-19 pandemic, its impact on mental-health, and the extent of their association. The results demonstrated that as time progressed, the pandemic: produced only moderate material and psychological change for both groups, although Turkey experienced more changes during the onset while North America experienced more changes later; both groups experienced mild-to-moderate distress while Turkey experienced more distress at the outset than North America; material and psychological changes were reliably associated with distress in North America, whereas in Turkey, only material change was reliably associated with distress.
Chapter 4 (Study-3) reports the results of a longitudinal survey of Southern Alberta, Canada residents, who experienced the 2013 flood. This follow-up study was conducted in 2019. It assessed the long-term transitional impacts of the Southern Alberta flood of 2013 and the relationship between this disaster-specific transition and mental-health. The results indicated that respondents reported lower material and psychological change in 2019 than in 2013. After six-years, post-traumatic-stress had a high correlation with material and psychological change; however, depression and anxiety were reliably related to psychological change only. Chapter 5 (Study-4) describes the outcomes of a longitudinal survey of British Columbia, Canada, and Western Germany residents who experienced the 201 wildfire and flood, respectively. Study-4 examined the transitional effect of the BC-fire and Germany-flood, and the associated mental-health consequences, immediately after the disasters and a year later. The results demonstrated that Germany-flood produced higher material and psychological change in 2021 than 2022; BC-fire produced higher psychological change in 2021 than 2022, but produced modest material change in both time-points. Also, the BC-fire group reported greater distress in 2021 than 2022, and the Germany-flood group reported moderate-to-severe distress in both waves; neither group experienced PTSD-like symptoms. Moreover, in both groups, evacuees experienced more change and distress than non-evacuees. Furthermore, over time, only psychological changes were reliably associated with distress in both groups. Chapter 6 provides a general summary of the findings and discusses the importance and implications of short- and long-term life changes brought by calamitic public events (COVID-19 pandemic, natural disasters) and their relationship with mental-health outcomes. Particularly, the present findings highlight the potential to enhance the understanding of long-term recovery needs after a crisis, for both communities and the individuals living within them
Daily Parenting and Adolescent Maladjustment: A Two-wave Multi-informant Daily Diary Study Before and During COVID-19
No full textIntroduction: The COVID-19 pandemic poses major challenges to parent–adolescent relationships under global stressors. Scant research has examined changes in the daily links between parenting behaviors and adolescent maladjustment before and after the onset of the pandemic. This study investigated the within-day associations between two parenting behaviors—positive parenting and psychological control—and three adolescent maladjustments—conduct problems, emotional problems, and negative affect—before and during COVID-19 through a two-wave multi-informant month-long daily diary study. Methods: A total of 3,041 daily observations from 30 Canadian parent–adolescent dyads (adolescents: M = 14.3, 39% female, 42% White; parents: M = 43.5, 72% female, 42% White) were assessed before (2019, nobservation = 778 and 772, for adolescents and parents, respectively) and during (2022, nobservation = 737 and 754) the pandemic. Results: Positive parenting and conduct problems decreased, while emotional problems increased from before to during COVID-19. Multi-level modeling showed that positive parenting was negatively linked with conduct problems and negative affect on the same day, whereas psychological control was positively linked with conduct problems and negative affect on the same day. Based on adolescent-reports, the onset of the pandemic suppressed the negative relation between positive parenting and negative affect, and amplified the positive relation between psychological control and emotional problems. Conclusions: These findings provide crucial evidence for changes in the daily links between parenting behaviors and adolescent maladjustment from pre- to amid-pandemic. Family-based interventions should target daily parenting behaviors during periods of stress and uncertainty to promote adolescent adjustment
Characterizing the Repeatability and Reproducibility of Cardiovascular Responses to Hypoxic Apneas
No full textBackground: We and others have demonstrated that voluntary apneas performed during acute and chronic hypoxia cause pronounced bradycardia and a higher incidence of cardiac arrhythmias compared to apneas under normoxic conditions. What remains unclear is the consistency of these responses. Therefore, we assessed the intra-individual repeatability (within-day: “day 1”) and reproducibility (between-day: “both days”) of cardiovascular responses to hypoxic apneas, including the genesis of arrhythmias. Methods: Sixteen participants (eight females, 25 ± 3 years, BMI 23.7 ± 3.4 kg/m2, mean ± standard deviation) completed four hypoxic apneas per day on consecutive days, all time-matched to the longest of two maximal apneas on day 1 (39 ± 16 s duration). We quantified heart rate (HR) and mean arterial pressure (MAP) repeatability and reproducibility using within-subject standard deviations (WSSD), [95% confidence interval (CI)]. We also assessed arrhythmia reproducibility using overall incidence (% of all apneas with an arrhythmia) and affected individuals’ incidence, the median and interquartile range of intra-individual arrhythmia occurrences, including only individuals who had at least one arrhythmia.
Results: Apneas caused pronounced bradycardia (day 1 = -17 ± 10 bpm; both days = -16 ± 11 bpm) and displayed excellent to good HR repeatability (day 1 WSSD = 5.0 bpm, 95% CI [4.2, 6.4]) and good reproducibility (both days WSSD = 5.9 bpm, 95% CI [5.2, 6.9]). MAP consistently increased during apneas (day 1 = +21 ± 10 mmHg; both days = +21 ± 10 mmHg) and displayed excellent to good repeatability (day 1 WSSD = 3.9 mmHg, 95% CI [3.2, 4.9]) and good reproducibility (both days WSSD = 4.7 mmHg, 95% CI [4.2, 5.5]). Arrhythmias occurred inconsistently with 53.9% overall incidence and 68.8% (37.5%, 87.5%) affected individuals’ incidence among 14 participants with ≥1 arrhythmia. No arrhythmia type occurred consistently; junctional escapes had the highest overall incidence at 28.9% in 11 participants, and premature ventricular contractions had the lowest overall incidence at 5.5% in three participants. Conclusions: Together, these data indicate that HR and MAP responses to hypoxic apneas are consistent at the intra-individual level, but that arrhythmogenic responses to hypoxic apneas cannot be predicted from a preceding apnea. This work helps define physiological responsiveness and prognostic utility under these conditions
Experimental and Analytical Studies of an Innovative System for Segmental Masonry Wall Construction
No full textOffsite Construction (OSC) technologies have enhanced the construction industry by introducing
prefabrication techniques that enable the production of building components in controlled factory
environments. OSC techniques enhance quality control, reduce construction timelines, improve
worker safety, and minimize material waste. Although OSC techniques have been widely adopted
in the precast concrete, steel, and mass timber industries, their use in concrete masonry
construction remains limited. Masonry construction has traditionally been reliant in on-site,
labour-intensive methods that hinder productivity – as a result, it remains underutilized despite its
inherent advantages: durability and outstanding thermal performance. To facilitate the adoption
of OSC paradigms in the masonry industry, an innovative prefabricated modular masonry panel
system specifically designed for tall masonry wall applications – such as those found warehouses,
industrial facilities, and school gymnasiums – is developed, together with a design methodology
that is amenable for inclusion in North American masonry standards. The study had both
experimental and numerical components. The experimental program involved two full-scale
masonry walls measuring 8.75 metres in height with a slenderness ratio (height over thickness) of
46. These walls, built using partially grouted concrete masonry units (CMUs), were subjected to
combined eccentric axial loads and cyclic lateral out-of-plane pressures. One wall was built with
OSC prefabrication techniques, while the second wall was built monolithically. Unbonded posttensioning (PT) systems were used to reduce cracking and promote structural integrity. Testing
under various base conditions and PT force levels demonstrated that the prefabricated wall system
exhibited comparable behaviour to the reference specimen in terms of strength, stiffness, and
deformation capacity. The prefabricated wall system reduced construction time by up to 60% compared to conventional masonry methods without significantly compromising structural
strength or performance.
In the numerical component of the study, an analysis model for segmental masonry walls was
developed using the finite element analysis (FEA) method. The analysis model was validated
against experimental data and then used to develop design provisions. A parametric study was
conducted to evaluate the influence of critical design parameters, including masonry compressive
strength, wall slenderness ratio, mild reinforcement, and PT stress levels, on the nominal moment
capacity () and moment magnification factor (Ψ). The analysis showed that the mild
reinforcement area and effective PT stress were the most significant factors influencing wall
capacity. Based on these findings, a mechanics-based design framework was developed through
regression analysis to predict and Ψ, so that the design equations incorporate secondary-order
effects and account for the contribution of the unbonded PT bars
Expansion of the Nutrient Stewardship Framework: Implications of the Right Soil on Synthetic and Biological Technologies in Western Canadian Spring Wheat Production
No full textTo ensure the continued success of the agricultural system in meeting global food demand, evaluation of novel strategies or technologies needs to be frequently pursued. This process has been exemplified in Canadian spring wheat (Triticum aestivum) by the 4R framework for nutrient stewardship. This framework embodies management practices to improve sustainability without compromising productivity, specifically around nitrogen (N) fertilizer use. Consequently, the advent of novel technologies and shift towards a soil health paradigm illuminates the challenge of capturing these new practices under the current framework. As such, there is a compelling case for the expansion of this framework to include a 5th R, the right soil. The proposed expansion will allow for new management practices beyond the traditional 4R’s of right source, right rate, right time and right place to permeate into the agricultural system under and established policy. Innovation among technologies that enshrine the essence of nutrient stewardship, such as enhanced efficiency fertilizers (EEF), and those that fall outside the traditional framework, such as microbial biotechnologies, needs to have their viability tested within the Canadian agricultural system. The objective of this body of work was to further our understanding of how new technologies, such as novel nitrogen stabilizers or arbuscular mycorrhizal fungi (AMF) inoculation, can influence N dynamics in Canadian spring wheat. Initially, the focus of this research was placed on gathering insights towards how currently available but not widely used EEF’s (i.e., alternative N source fertilizer formulations and various N stabilizers) could impact the crop productivity of Canadian wheat. This comparison among different N source fertilizers revealed that banded ammonium-nitrate based formulations can offer minimal crop productivity benefits over banded urea. Moreover, incorporation of banded nitrification or urease inhibitors into fertilizer regimes (i.e., EEF’s) provided little agronomic differentiation in spring wheat. This was likely due to the common practice of banding fertilizer limiting N loss potential under environmental conditions experienced in the Canadian Prairies. These observations highlight the need for new technologies or practices to be incorporated into the current paradigm in order to help drive future crop productivity advancements. New technologies that focus on soil health or functionality may have substantial impacts on already productive ecosystems. This can be emulated by the inoculation of symbiotic microbes involved in soil nutrient cycling (i.e., AMF) and has been proposed to be an untapped potential resource. Inoculation of the AMF species Rhizophagus irregularis in spring wheat has historically been met with mixed outcomes but has been shown to substantially influence N cycling and loss mechanisms. Testing of AMF inoculants in Canadian spring wheat has been limited, meanwhile there has been no assessments on the viability of using EFF’s in conjunction with novel biotechnologies. This research evaluated the individual practice of applying nitrification inhibitors or inoculating with Rhizophagus irregularis in a Canadian prairie spring red (CPSR) wheat genotype. This led to reduced N2O emission potential under each individual technology but increased N2O emissions when applied together in a greenhouse setting. Additionally, the field-based efficacy of commercial Rhizophagus irregularis inoculation was tested on numerous Canadian western red spring (CWRS) wheat varieties and a single CPSR variety. The field-based testing showed consistent crop productivity improvements occurring in only the CPSR wheat variety under specific site conditions. This disparity among wheat class was likely due to the physiological differences in varieties, while site specific conditions were influenced by N fertilization practices. These findings highlight the potential of novel biotechnologies to improve wheat productivity, while illuminating the need to appropriately capture their potential within a policy framework. This lends credence to the expansion of the 4R nutrient stewardship framework to include a 5th R, the right soil