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Impacts of anthropogenic land transformation on habitat amount, fragmentation, and connectivity in the Adirondack-to-Laurentians (A2L) transboundary wildlife linkage: Implications for conservation and ecological restoration
Get PDFHabitat loss and fragmentation, due to anthropogenic land transformation, is the leading cause of species declines and biodiversity loss worldwide. Habitat loss and fragmentation transform landscapes into a heterogeneous array of habitat fragments of smaller total habitat area, isolated from each other by a human-dominated matrix. This results in long-term changes in ecosystem structure and function, and an overall reduction in species abundance and movement ability between fragments. Globally, 56% of all terrestrial mammals have transboundary geographic ranges. In contrast, most conservation initiatives do not cross political boundaries. The Adirondack-to-Laurentians (A2L) transboundary wildlife linkage connects wilderness areas in
the northeastern United States with southeastern Canada. Although the region contains many habitats of high ecological integrity and biodiversity, ceaseless anthropogenic land transformation within the A2L may be putting transboundary connectivity at risk. Changes in
landscape structure, due to anthropogenic land transformation, that occurred within the A2L between 1992 and 2018 were quantified, and priority areas for conservation and restoration were identified. The results suggest that to achieve long-term functionality of the A2L, collaborative and coordinated measures will be necessary to preserve the integrity of the Québec portion, restore extensive habitat in eastern Ontario, and reestablish or maintain connectivity throughout the linkage. The results can be used to inform conservation policy and land-use planning throughout the region. Left unaddressed, continued anthropogenic land transformation is likely to have additional detrimental effects on the ability of the A2L to function as a transboundary wildlife linkage
White Heat: Hawai‘i’s Territorial Elites and the Reforms of the Honolulu City and County Police Department
Get PDFMy thesis looks to highlight elites’ use of policing ideology in their quest for continued access to state power. The reforms of the Police Act of February 1, 1932, were introduced by Republican lawmakers to safeguard the oligarchic rule of the Big Five sugar companies in the wake of the United States’ Federal Government’s scrutiny of the territory’s system of law enforcement after the Ala Moana trial and the murder of Joseph Kahahawai. The reforms represented the culmination of more than a decade of advocacy and public inquiries by civic leaders, progressive women, and the territory’s English language press. In times of crisis, Honolulu’s elites turned to the international network of policing experts to reform the Honolulu City and County Police Department and affirmed its status as the protector of the ruling class. In the first chapter, I look at how the police proved instrumental in defining the notion “security” for haole elites who understood the growing presence of racialized people outside of the plantation and in Honolulu’s urban landscape as a threat to the sugar planter’s oligarchy’s social order. I examine three key moments in Honolulu’s history where elites agitated for an increase in police repression of racialized people: the 1920 Sugar Workers’ Strike, the Kaka‘ako case of 1923, and the 1924 Filipino Sugar Workers’ Strike. In the second chapter, I dig into the ideological and legislative origins of the Police Act of February 1, 1932. I identify August Vollmer as an imperial importer (Go, 2020) of militarized technologies whose Berkeley Police Department served as the principal reference for the reforms envisaged by Honolulu’s lawmakers. The principles of professional policing promulgated by Vollmer provided elites with the justification and the means to insulate their system of oligarchic control from the interference of the federal government and the majority Native Hawaiian and Asian population. The changes put in motion by the Hawaiian territorial legislative house in 1932 were cemented during the 14-year tenure of Honolulu’s second police chief William A. Gabrielson. Gabrielson, a former Berkeley Police Department officer, transformed the Honolulu City and County Police Department into a state-of-the-art police force proficient in the type of surveillance operations the FBI and the U.S. military would require the police department to conduct during the Second World War
TRANSFORMING PARKING FACILITIES TO ACCOMMODATE ELECTRIC VEHICLES: A CAPACITATED MULTI-FACILITY LOCATION PROBLEM APPROACH.
Get PDFThis study addresses the limitations of Electric Vehicles Charging Stations (EVCS) in Montréal, Québec. Momentum, the growth of Electric Vehicles (EVs) is projected to accelerate substantially. However, this growth is hindered by limited EVCS, particularly in shopping center settings where high cost and spatial limitations pose significant challenges. This study addresses these gaps by proposing an optimization model to support cost-effective EVCS placement.
The problem employs Mixed-Integer Nonlinear Programming (MINLP), categorizing it as a capacitated multi-facility location allocation challenge. This approach is designed to minimize the total lifecycle costs for property owners, including costs related to equipment, electrical system equipment, operational and maintenance, fixed costs, and dismantling expenses.
The optimization process involves determining the desired number of ports in the parking, based on the available estimation of the EV growth as a first step. Afterward, determining parking blocks based on the parking size to allocate the different types of ports into them. Then, various port type combinations, are distributed into all the generated block combinations. The proposed formulation is a Life Cycle Cost (LCC)-Based optimization designed to achieve minimum costs. The solution introduces a combinatorial optimization algorithm that combines dynamic programming and brute-force search to ensure all potential configurations are considered.
In conclusion, this study provides a framework for shopping center owners to adapt their parking facilities to EVs. The proposed cost formulation provides a financially sustainable solution for EVCS placements. Through this approach, this study offers a practical method to enhance EV infrastructure within commercial indoor parking environments, balancing financial and logistical consideration
The Physicochemical Impact of Tocopherols on Lipid Membranes
Get PDFLung surfactant is the lipid-protein monolayer at the interface between the air and the liquid lining the alveoli. It serves to ensure the lungs stay inflated during inhalation and to reduce the surface tension to prevent its collapse at the end of expiration. Exposure to e-cigarette additives vitamin E (a−tocopherol) and its acetate derivative vitamin E acetate (a−tocopherol acetate) through vaping has been linked to e-cigarette or vaping product use-associated lung injury (EVALI). This condition disrupts normal lung function, leading to severe respiratory distress that can cause hospitalization for difficulty in breathing, and, in some cases, lung collapse or death. Using a Langmuir balance, excess area calculations, Brewster angle microscopy (BAM), atomic force microscopy (AFM) and molecular studies such as grazing incidence X−ray diffraction (GIXD) and X−ray reflectivity (XR), the effects of these additives on the lung surfactant monolayer film have been examined and changes in surface activity, morphology, and molecular organization of the film assessed. The introduction of a−tocopherol and a−tocopherol acetate alters the fluidity, phase balance and modifies the composition of the different phases present. These changes could potentially impair normal lung surfactant function. This research also addresses potential short-term impacts on lung surfactant function due to vaping. In addition to its effects on lung surfactant, we studied a−tocopherol, the most bioavailable form of vitamin E, for its interaction with common membrane lipids. Known as a potent membrane-soluble antioxidant, a−tocopherol plays an irreplicable role in preventing lipid peroxidation, which can otherwise lead to the degradation of cellular membranes, or even cell death. We used the same techniques to explore the mixing behaviour of a−tocopherol with both saturated and unsaturated membrane lipids. This revealed how a−tocopherol’s interactions vary based on the degree of lipid unsaturation, independent of the lipids headgroup
The Effects of Ground Motions Characteristics and Higher Modes on the Seismic Response of Steel Strongback Braced Frame Buildings
Get PDFTo mitigate the weak-storey response that characterize traditional steel braced frames under seismic excitations, researchers proposed the Strongback Braced Frame (SBF) system, which is composed of a primary ductile system and an elastic vertical truss (strongback, SB). Although this system is not new, a comprehensive design method for sizing the SB truss members is lacking. It is worth mentioning that higher-mode forces are not limited by the yield mechanism of ductile system and they lead to large inertial effects relative to the first-mode response. Current studies conducted on SBF are limited for low-rise buildings where the strongback truss is integrated into the half side of ductile braced frame which leads to large ductile brace sizes. Hence, installing the SB truss exterior to the ductile system is beneficial.
In this research work, the SBF is derived from Moderately Ductile Concentrically Braced Frame (MD-CBF) with split-X braces and two SB configurations are considered: adjacent exterior and reversed exterior.
The main objectives are: i) to simplify the design method for SBF to be appealing for practitioners, ii) to analyse the effects of ground motions characteristics and higher modes on the nonlinear seismic response of low-rise buildings braced by Strongback Braced Frame (SBF) with exterior SB, and iii) to discuss the seismic performance of SBF against that of traditional MD-CBF.
The case study is a 4-storey SBF office building located on Site Class C in Victoria, B.C. Two sets of ground motions were considered in analysis: the short-duration crustal ground motions, and long-duration subduction ground motions characterised by Trifunac duration > 60 s. Detailed numerical models were developed in OpenSees and the nonlinear seismic responses of buildings were expressed in terms of interstorey drift (ISD), residual interstorey drift (RISD), floor acceleration (FA) and storey shear. To identify the types of failure mechanism, the incremental dynamic analysis (IDA) was employed and the IDA curves were developed considering both sets of ground motions. The collapse margin safety was assessed and the performance of SBF building was compared against that of the benchmark 4-storey MD-CBF building.
The SBF system is found effective in mitigating the weak-storey response, distributes ISDs uniformly along the building height, exhibits reduced residual drift, and provides about 50% larger safety margin compared to traditional MD-CBF systems. In addition, the SB truss is able to respond in the elastic range while engaging all ductile braces to dissipate the input energy. Although one or even two ductile braces experienced fracture caused by low-cycle fatigue, the SB is able to prevent the occurrence of dynamic instability. Moreover, the subduction zone records that are reach in high frequency content, excite the higher modes and in consequence amplify the upper floors responses. Thus, the type of failure mechanism of SBF is strongly influenced by the mean period of ground motions; hence, the records with short mean period trigger amplified demand at upper floors, while those with longer mean period trigger damage at lower floors. It was also found that the SBF buildings show sufficient collapse margin safety and the SB location slightly influences the seismic response of SBF. However, the 4-storey MD-CBF building showed a borderline pass of margin safety criteria and is not recommended in subduction zone prone regions.
Future research is required to investigate the higher modes effect on building height, as well as the impact of differed types of ductile braces on the global response of steel SBF buildings
Flow Characteristics of Transitions in Open Channels
No full textThe characteristics of turbulence in open-channel transitions have important implications for hydraulic engineering. This study considers a warped transition that links a rectangular channel section with a relatively large trapezoidal channel section. The change in cross-sectional shape as well as area causes an adverse pressure gradient. As a result, the primary flow separates from the transition sidewalls, turbulence eddies form, and losses of flow energy occur; these conditions reduce hydraulic efficiency and are highly undesirable. Previous researchers have made great efforts to reduce energy losses and improve hydraulic efficiency but have not addressed the issues adequately. This study aims to explore the effectiveness of introducing a honeycomb with small open cells to the transition in order to improve the flow characteristics. This study took an experimental approach. Three-dimensional instantaneous velocities were measured using an acoustic Doppler velocimeter. An analysis of the measurements produced cross-sectional distributions of the longitudinal flow velocity, secondary flow, turbulence kinetic energy, and Reynolds shear stress. The energy losses were determined, and they were compared between the case of a plain warped transition (without a honeycomb) and the case with a honeycomb. The presence of the honeycomb in the transition improved the flow characteristics, reducing flow separation, energy losses, and turbulence strength. The honeycomb helped increase flow uniformity and decrease the maximum velocity in the transition and farther downstream. A potential benefit of a decreased maximum velocity is a decreased risk of channel erosion. The honeycomb worked to prevent the formation of large turbulent eddies that are known to be energy-bearing while avoiding excessive frictional losses of flow energy because the contact area of the passing fluids with the open cells is small. The mechanism at work is that the small open cells effectively limit the size of the largest possible turbulent eddies while distributing the approach flow evenly across the width of the transition. For practical application, a honeycomb can easily be installed at the entrance of a new or existing transition for beneficial effects. This study has contributed to improving the design of irrigation, drainage, and hydropower channels, all of which typically need a transition
CityEnergy Suite: A Holistic Approach to Modeling Occupant Behavior, Electric Vehicle Charging, and Demand Response in Urban Environments
No full textQuebec's ambition to achieve net-zero emissions by 2050 poses significant challenges in decarbonizing the building and transportation sectors while managing increasing electricity demand. A major obstacle is handling the temporal dynamics of electricity usage, especially unpredictable peak periods influenced by weather, economic activities, and consumer behavior. Efficient demand-side management (DSM) strategies, such as demand response (DR) and Vehicle to Grid (V2G), are essential to shift and flatten peak demand, ensuring a more sustainable and economically viable energy transition.
This thesis introduces the CityEnergy Suite, a comprehensive modeling framework for simulating residential energy-related behavior, electric vehicle (EV) charging, and DR strategies. Leveraging open-access datasets like Census data and energy surveys, the model generates high-resolution load profiles. The CityEnergy Suite employs a modular, agent-based approach to assess the aggregate impact of occupant behavior on the electrical grid and explore future energy scenarios. It comprises three key components: CityAgent, CityLoad, and CityCharge.
CityAgent creates a detailed synthetic population model tailored to the Montreal region, incorporating diverse household compositions and socio-economic characteristics. CityLoad produces stochastic energy load profiles that consider household attributes and appliance usage. CityCharge models urban EV charging demand, enabling analysis of different charging behaviors and penetration scenarios on the grid.
The findings provide crucial insights for developing decarbonization and DSM strategies, highlighting the potential of engaging small customers to support grid stability through load shifting, peak shaving, and emerging V2G technologies. The CityEnergy Suite offers a robust framework for designing inclusive and effective energy policies, contributing significantly to Quebec's decarbonization efforts
Detecting Collusion in Public Procurement: A Comparative Study of Machine Learning Models
Get PDFDetecting collusion in public procurement is critical to ensure fair and transparent practices in government acquisitions. Bid collusion in auctions poses a major challenge in public procurement by causing unfair price hikes through unlawful cooperation among competing firms, consistently affecting the overall supply chain. This study uses machine learning methods to investigate collusion in public procurement processes. It delves deeply into exploring multiple machine learning models such as random forests, extra tree classifiers, support vector classifiers, Neural Networks, Gradient Boosting, and various combinations of models for collusion detection. First, the models were trained using available data, followed by the inclusion of screening variables derived from bid information as additional features. The additional features were fed to the models, which went through fine-tuning of parameters. Additionally, comparative analyses were carried out to evaluate the merits and drawbacks of each model. Metrics including Accuracy, balanced accuracy, precision, recall, F1-score, and ROC-AUC score were evaluated, providing a comprehensive evaluation framework. Various settings were used to compare which set of inputs gives the highest accuracy in collusion detection. The ROC-AUC analysis brought forward crucial insights, particularly regarding models' abilities to minimize false positives while maximizing true positives. Models like Random Forest and Gradient Boosting demonstrated superior performance, showcasing lower false positive rates—a crucial aspect when identifying collusion in public procurement. Additionally, the study underscores the significance of feature engineering in collusion detection. Specifically, attributes like screens - CV, SPD, DIFFP, RD, SKEW, KURTO, and KS significantly aid algorithms in processing data effectively to identify collusion patterns. The outcomes of this study carry significant implications for both the specific domain under investigation and the broader field of collusion detection. Ultimately, this research provides a valuable guide for policymakers, procurement officers, and data scientists, offering valuable insights into the effective machine learning techniques tailored for detecting collusion in public procurement
“When Cooking Japanese Style, It Helps If You Have An American Friend”: American Cold War Discourse on Japanese Cuisine, 1945-1992
Get PDFThis thesis explores the evolution in American discourse on Japanese cooking from the end of World War II through the end of the Cold War. During this time of important changes and tensions in US-Japan relations, Japanese cuisine went from a niche, exotic novelty to a monument of fine dining. Nevertheless, that discourse remained largely static throughout the period. This stasis is imputable to the fact that, at least on a national level, white, educated, upper-middle class writers —rather than Japanese-Americans— popularized Japanese cuisine in the United States. Those writers often perpetuated older Orientalist tropes and used Japanese cuisine as a mean to accrue cultural capital and perform a form of cosmopolitanism that had become fashionable during the Cold War era. This research is based on the analysis of cookbooks, restaurant reviews, mostly from the New York Times, and magazines articles from Gourmet and Bon Appétit published between 1945 and 1992.
Indoor Depth Map Completion via Mesh-based Discrete Geometric Processing
Get PDFDepth measurement serves as a pivotal technology with widespread applications, but limitations of commodity depth sensors often result in noisy and incomplete depth maps for indoor scenes. In response, this study introduces a discrete geometric processing-based method aimed at enhancing the completeness of indoor depth maps, particularly in intricate and challenging scenes. The proposed approach involves transforming raw depth maps into a quadrilateral mesh surface and addressing missing depth information through a mesh deformation framework. The mesh deformation framework employs iterations to update constraints on quadrilateral facets until convergence, tackling normal constraints, position constraints, and perspective projection constraints. This optimization problem is resolved using a combination of local shaping and global fusing strategies. In the local step, each quadrilateral facet is projected from the physical imaging plane into camera coordinate system based on perspective projection, preserving only orientation information. The global step then propagates location information through vertices shared by connected facets. Uncertainties in input normal and observed depth information are addressed through updating strategies. Experimental results on 30 selected examples from ScanNet dataset demonstrate the superiority of the proposed method over two existing techniques quantitatively and qualitatively. Specifically, the method excels in addressing depth discontinuity around object boundaries, producing clear disconnections, while competing methods exhibit errors and stretched distortions. Validating normal and depth updating strategies, the paper confirms the effectiveness of processing depth discontinuity in reducing completion errors. The robustness of the method is further affirmed by energy reductions in both normal and position aspects across iterations