identifier: Foroughi, Shervin  (2018) Additive Manufacturing of Free Standing Structure from Thermally Cured Resins.  Masters thesis, Concordia University.

abstract:
3D printing or Additive Manufacturing is a class of manufacturing processes for creating three-dimensional objects. In an additive manufacturing process, an object is fabricated by printing multilayers of material successively until the final desired size of an object is obtained. The 3D printing technology can be used for both rapid and functional prototyping as well as small batch production. Stereolithography, Selective Laser Sintering and Fused Deposition Modeling are three common technologies for 3D printing of plastics which employ photosensitive resins or thermoplastic materials as a printing material. Laser and heat are the energy sources in these technologies.
In this research, a novel additive manufacturing technology using high intensity ultrasound as the energy source is introduced. Commercial thermally cured resin will be employed as a printing material. For a better understanding of developing a method for 3D printing of this kind of resin, the numerical analysis of the process is performed. In order to get familiar with the 3D printing process, a simple CAD model of an object is printed using one of the commercial 3D printers which work based on the stereolithography technology. Using the simulation results and finding the quality of 3D printed parts produced by a mentioned standard 3D printer, the employed setup for performing experiments will be introduced. Then, the obtained results from experiments are presented. Experiment results are utilized to find the optimum condition for performing the 3D printing with this new technology. Therefore, by applying the optimum conditions and using selected resin, a simple 3D object will be printed. The printing process takes about 10 minutes which is the fastest time for 3D printing. Measured dimensions of a product show that the resolution of printed part is affected by a size of a focal region, accuracy in determination of its location during the process, and streaming inside the cavity.


identifier: England, Sara Nicole  (2018) Ideal Citizens, Better Workers: National Cash Register Company’s Garden Programmes and Factory Tourism (1897–1913).  Masters thesis, Concordia University.

type: Thesis NonPeerReviewed

abstract:
Public concerns about the degrading effects of industrial labour on workers' moral and physical development in the 1880s led some American factories to institute garden programmes for their workers. Companies undertaking various forms of welfare work, including the provision of gardens and recreational spaces for employees, initiated factory tours for a curious, mostly middle-class, public to witness the “human side” of industrial relations.

National Cash Register Company (NCR) in Dayton, Ohio was among the first to form a large-scale tourist programme to showcase its most recognized form of welfare work: the comprehensive garden programmes for employees, nearby residents, and children. NCR’s factory tour and garden programmes (organized into three components: landscape gardening, children’s gardens, specifically the Boys’ Gardens, and the civic garden campaign) form the subject of this thesis. Employing the concept of the “exhibitionary complex” to factory tourism, the author contextualizes NCR’s factory tour within a broader cultural practice of exposition visits in which the middle class exercised their cultural and moral authority by regulating the working class.

This thesis argues NCR’s garden programmes were prescribed to working-class subjects to raise more productive and loyal workers and valued citizens while, at the same time, imparting middle-class virtues about the “respectable family” and suburban home. Gardens and tourism, together, formed a managerial strategy for controlling workers and residents. By focusing on the civic gardening campaign and the children’s gardens on the factory’s grounds, the author examines the gendered involvement of women and boys in NCR’s garden programmes.


identifier: Olsthoorn, Dave  (2018) Determining Key Parameters and Guidelines for the Design of an Electrically Activated Concrete Slab for Peak Shifting in a Light-Weight Residential Building in a Northern Climate.  Masters thesis, Concordia University.

abstract: A thermal storage system for residential buildings in a Northern climate is developed for electrical peak shifting and shaving. To facilitate implementation, only commercially available products are used for the system in conjunction with common construction methods. A thermal model is created with the TRNSYS simulation software and validated using data from a two-year monitoring campaign. The thermal model is used to identify key system parameters and propose system design guidelines. It is determined that, for residential buildings with a footprint varying between 80 m2 to 200 m2, the basement floor slab can be used for thermal storage with electrical heating cables and that the entire basement heating load can, during the peaks, be shifted to off peak periods. The optimal assembly for the basement floor is composed of 102 mm of extruded polystyrene insulation followed by 152 mm of concrete. The electric heating cables are positioned at the bottom of the concrete layer. This assembly can be controlled with the air set point temperature. The air setpoint temperature of basement rooms during charging needs to be 2 degC higher than the air setpoint temperature during normal operating conditions. The required charging time for building footprints of 80, 120 160 and 200 m2 corresponds to 6.00, 5.51, 5.05 and 4.66 hours, respectively.


identifier: Kuzyk, Olivia  (2018) Knowing who knows: Infants’ metacognitive and causal learning abilities guide selective social learning.  Masters thesis, Concordia University.

abstract: Given the widespread interest in the development of children’s selective social learning, there is mounting evidence suggesting that infants prefer to learn from competent informants (Poulin-Dubois & Brosseau-Liard, 2016). However, little research has been dedicated to understanding how this selectivity develops. The present study investigated whether causal learning and precursor metacognitive abilities govern discriminant learning in a classic word-learning paradigm. Infants were exposed to a speaker who accurately (reliable condition) or inaccurately (unreliable condition) labeled familiar objects, and were subsequently tested on their ability to learn a novel word from the informant. The predictive power of causal learning skills and precursor metacognition (as measured through decision confidence) on infants’ word learning was examined across both reliable and unreliable conditions. Results suggest that infants are more inclined to accept an unreliable speaker’s testimony on a word learning task when they also lack confidence in their own knowledge on a task measuring their metacognitive ability. Additionally, when uncertain, infants draw on causal learning abilities to better learn the association between a label and a novel toy. This study is the first to shed light on the role of causal learning and precursor metacognitive judgments in infants’ abilities to engage in selective trust.


identifier: Bajwa, Navneet Kaur  (2018) Modelling and Simulation of Blockchain based Education system.  Masters thesis, Concordia University.

abstract:
Since Bitcoin’s launch in early 2009, the industrial and academic interest in Blockchain and other cryptocurrencies have grown rapidly. Blockchains have been applied in many areas outside of finance such as healthcare, commerce and judiciary already. This technology promotes the creation of a decentralized environment where transactions and data are not under the control of any third-party organization. Blockchain is a fundamentally new technology that could revolutionize the future of transaction-based exchanges.  Extensive research is being done in order to implement this technology various sectors. Blockchain technology comes with an edge of inbuilt auditability, trust and transfer of value which also makes it irresistible.
This work explores an agent based Blockchain-based Education System through mathematical modeling and simulation tools. The model is constructed to explore how Blockchain technology can be used to verify credit score of students, identify the occurrence and prevention of potential attacks.  Along with technical characteristics of Bitcoin and Blockchain; cost, time and behavioural considerations of the system are also made. This is followed by analysing of the number of transactions, size of blockchain, network efficiency, cost analysis of the system along with the network efficiency. The proposed model, based on the blockchain technology shifts the education grading and credit rewarding system from the analog and physical world into a globally efficient, transparent and universal version. The work contributes a foundation for advancing current understanding of blockchain systems, and to further the development of simulation models of blockchains.


identifier: Parr, Timothy  (2018) Presence and Absence: The World Trade Center in Film Before and After Sept. 11, 2001.  Masters thesis, Concordia University.

abstract: This thesis traces the changing visual significance of the World Trade Center (WTC) in fiction film, from its completion in 1973, to its haunting afterlife since September 11, 2001. This study gathers and critically assembles various representations of this financial icon in order to find new meaning for the representation of the towers in film prior to 2001, along with the significance that they acquired in light of their material destruction. To do so, this study relies on a textual analysis of selected films in which the towers appear, while utilizing a stylistic and formal analysis to dissect their visual and narrative treatment. It locates the towers as a crucial node within global transnational capitalism and draws from a number of critical texts, methods, and traditions, including those of Siegfried Kracauer and Walter Benjamin, particularly, the conceptualization of the image as a ruin of its profilmic moment, and the afterlife of the image. Essentially,this thesis reconsiders the towers’ status as traces in photographic media and audiovisual culture,and examines how they have resisted a totalizing meaning. Retrospectively returning to moving images, viewers notice objects, and events that escaped their notice upon first viewing, which is the case with the Twin Towers in film post-2001 as they affect the viewer’s response in new ways.


identifier: Tanash, Moayad  (2018) Hub Network Design and Discrete Location: Economies of Scale, Reliability and Service Level Considerations.  PhD thesis, Concordia University.

abstract: In this thesis, we study three related decision problems in location theory. The first part of the dissertation presents solution algorithms for the cycle hub location problem (CHLP), which seeks to locate p-hub facilities that are connected by means of a cycle, and to assign non-hub nodes to hubs so as to minimize the total cost of routing flows through the network. This problem is useful in modeling applications in transportation and telecommunications systems, where large setup costs on the links and reliability requirements make cycle topologies a prominent network architecture. We present a branch and-cut algorithm that uses a flow-based formulation and two families of mixed-dicut inequalities as a lower bounding procedure at nodes of the enumeration tree. We also introduce a greedy randomized adaptive search algorithm that is used to obtain initial upper bounds for the exact algorithm and to obtain feasible solutions for large-scale instances of the CHLP. Numerical results on a set of benchmark instances with up to 100 nodes confirm the efficiency of the proposed solution algorithms. In the second part of this dissertation, we study the modular hub location problem, which explicitly models the flow-dependent transportation costs using modular arc costs. It neither assumes a full interconnection between hub nodes nor a particular topological structure, instead it considers link activation decisions as part of the design. We propose a branch-and-bound algorithm that uses a Lagrangean relaxation to obtain lower and upper bounds at the nodes of the enumeration tree. Numerical results are reported for benchmark instances with up to 75 nodes. In the last part of this dissertation we study the dynamic facility location problem with service level constraints (DFLPSL). The DFLPSL seeks to locate a set of facilities with sufficient capacities over a planning horizon to serve customers at minimum cost while a service level requirement is met. This problem captures two important sources of stochasticity in facility location by considering known probability distribution functions associated with processing and routing times. We present a nonlinear mixed integer programming formulation and provide feasible solutions using two heuristic approaches. We present the results of computational experiments to analyze the impact and potential benefits of explicitly considering service level constraints when designing distribution systems.


identifier: Yang, Xi  (2018) Information Geometry of Statistical Models.  Masters thesis, Concordia University.

abstract: Information Geometry is a relatively young branch of Mathematics, which roots back to studies of invariant geometrical structure involved in statistical inference. It de- fines a Riemannian metric together with dually coupled affine connections in a mani- fold of probability distributions. These structures provide tools not only for studying statistical inference but also for research in wider areas of information sciences, such as machine learning, signal processing, optimization, and even neuroscience, not to mention mathematics and physics. The aim of this thesis is to give a brief intro- duction to Information Geometry with focus on the exponential family. In Chapter 1, we first introduce the notion and basic properties of statistical models. We then define some common notions in information geometry such as Fisher information, Christoffel symbols, connections, Skewness tensor, geodesic and Jeffreys Prior. We also introduce the geometry of entropy, including entropy, Kullback-Leibler diver- gence (or relative entropy) and information energy on statistical models. Chapter 2 focuses on the geometry of the exponential family of probability distributions. Ex- amples and properties of exponential families are firstly discussed in this chapter. Fisher metric and geodesics are worked out explicitly for common exponential fam- ilies. Chapter 3 contains important examples of exponential families for which the entropy, Kullback-Leibler relative entropy and information energy are worked out explicitly. This chapter deals also with the problem of finding the density of maximum entropy subject to the first N moment constraints, with unique solutions for the cases N ≤ 2.


identifier: Hof, Lucas Abia ORCID: https://orcid.org/0000-0002-0495-9572 <https://orcid.org/0000-0002-0495-9572>  (2018) High-precision micro-machining of glass for mass-personalization.  PhD thesis, Concordia University.

abstract:
With the fourth industrial revolution manufacturing industry faces new challenges. Small batches of personalized parts, where the geometry changes per part, must be produced in an economically viable manner. In such cases of mass personalization new manufacturing technologies are required which can keep manufacturing overhead related to change of part geometries low. These processes need to address the issues of extensive calibration and tooling costs, must be able to handle complex parts and reduce production steps. According to recent studies hybrid technologies, including electrochemical technologies, are promising to address these manufacturing challenges.
At the same time, glass has fascinated and attracted much interest from both the academic and industrial world, mainly because it is optically and radio frequency transparent, chemically inert, environmentally friendly and it has excellent mechanical and thermal properties, allowing tailoring of new and dedicated applications. However, glass is a hard to machine material, due to its hardness and brittleness. Machining smooth, high-aspect ratio structures is still challenging due to long machining times, high machining costs and poor surface quality. Hybrid methods like Spark Assisted Chemical Engraving (SACE) perform well to address these issues.
Nevertheless, SACE cannot be deployed for high-precision glass mass-personalization by industry and academia, due to 1) lack of process models for glass cutting and milling, relating SACE input parameters to a desired output, 2) extensive calibration needed for tool-workpiece alignment and tool run-out elimination, 3) part specific tooling required for proper clamping of the glass workpiece to attain high precision.
In this study, SACE technology was progressively developed from a mass-fabrication technology towards a process for mass-personalization of high-precision glass parts by addressing these issues. Key was the development of 1) an (empirically validated) model for SACE cutting and milling process operations allowing direct relation of the machining input to the desired machining outcome, enabling a dramatical increase of automation across the manufacturing process workflow from desired design to establishing of machinable code containing all necessary manufacturing execution information, 2) in-situ fabrication of the needed tooling and 3) the use of low-cost rapid prototyping, eliminating high indirect machining costs and long lead times.
To show the viability of this approach two novel applications in the microtechnology field were proposed and developed using glass as substrate material and SACE technology for rapid prototyping: a) fabrication of glass imprint templates for microfabricating devices by hot embossing and b) manufacturing of glass dies for micro-forming of metal micro parts.


identifier: Fallah, Panteha  (2018) Fabrication and optimization of 3D metallic parts using electroplating of additively manufactured parts.  Masters thesis, Concordia University.

abstract:
Additive manufacturing (AM) technologies can be used to manufacture metallic and non-metallic
parts. Combination of electrochemistry and additive manufacturing technology makes possible the
fabrication of different shapes and geometrical features with very smooth surfaces.
In this thesis, an overview of the basics of electroless copper plating, copper electroplating, AM technologies and their applications are covered. An introduction to how an AM part is produced, how electroless copper plating is carried out on a non-conductive surface, how an electroless copper plated part can be electroformed, how to obtain sufficient thickness of the copper coating while keeping the surface smooth have been shown.
FDM (fused deposition modeling) technology is used to print a 3D ABS (Acrylonitrile butadiene styrene) part due to its low manufacturing cost and a minimal amount of waste material. Then, a
produced ABS part got conductive through electroless copper plating process enabling the electroplating afterward.
Optimal parameters of electroless copper plating and copper electroplating (in three different modes: galvanostatic, potentiostatic and pulse-potentiostatic) on a planar geometry are achieved with the goal of obtaining a smooth surface.
The results show that the surface roughness of a produced 3D metallic part can be significantly lowered using pulse electrodeposition. Although the presence of additives in the solution can affect the surface roughness and properties of the deposit, using pulse electroplating technique is offered as an alternative to the additives which are almost toxic, and add impurities within copper deposit.


identifier: Wang, Yudong  (2018) Seismic Performance of Steel Buildings with Braced Dual Configuration and Traditional Frame Systems through Nonlinear Collapse Simulations.  Masters thesis, Concordia University.

abstract:
ABSTRACT
Seismic Performance of Steel Buildings with Braced Dual Configuration and Traditional Frame Systems through Nonlinear Collapse Simulations
Yudong Wang
Traditional concentrically braced frames, CBF, are stiff and provide limited to moderate ductility, while moment resisting frames, MRF, are able to dissipate seismic energy when undergoing large lateral displacements. However, these traditional earthquake resistant systems do not show uniformly distributed damage along the building height. Changes in structural proprieties during nonlinear hysteresis behaviour may lead to drift concentration and weak-storey response. Moreover, both traditional systems are susceptible to long-duration subduction earthquakes.
The pursuit of these issues led to the concept of utilizing multiple-resisting structural systems that act progressively so that the overall seismic resistance is not significantly reduced during long-duration earthquakes. The structural system consisting of a rigid braced frame that provides primary stable cyclic behavior and a moment frame acting as a backup system with good flexural behavior is the steel Braced Dual System studied herein.
The objectives of this study are: a) to investigate the seismic response of steel Braced Dual building from yielding to failure, as well as, to identify the types of failure mechanism; b) to assess the seismic response of Braced Dual System against the traditional MRFs and CBFs with moderate ductility through incremental dynamic analysis; c) to evaluate the effect of long duration subduction earthquakes versus crustal type earthquakes on these building systems through collapse safety criteria using FEMA P695 procedure and to assess the probability of exceeding defined performance levels using fragility analysis.
To carry out these objectives, detail numerical models were developed using the OpenSees framework. The prototype 8-storey office building is located on firm soil in Vancouver, B.C. and is subjected to two sets of crustal and subduction ground motions. Two traditional earthquake resistant systems (MD-CBF, MD-MRF) and the Braced Dual System are considered. Design is conducted according to NBCC2015 and CSA/S16-14.
From nonlinear time history analysis, the following results are reported: for the Braced Dual System, two types of failure mechanism involving either one floor or two adjacent floors (in general the bottom floors) were identified which also involve flexural yielding of MRF beam of critical floors; the Braced Dual System provides larger ductility than the MD-CBF, shows significant increase of seismic resistant capacity for similar seismic demands, provides the largest collapse margin ratio and collapse safety capacity under both earthquake types. In addition, the building with Braced Dual System shows a progressive seismic behavior and a more uniform damage distribution along the building height. From fragility analysis resulted that at Collapse Prevention (CP) limit state, the Braced Dual System experiences 100% probability of exceedance after it was subjected to two times larger seismic demand than the MD-CBF or MD-MRF systems. All studied structural systems are sensitive to long duration subduction earthquake.


identifier: Misiuk, Marlene  (2018) La Donna e La Maniera Devota:Lavinia Fontana, Sacred Imagery and the Natural Sciences in Sixteenth-Century Bologna.  Masters thesis, Concordia University.

abstract: Women’s contribution to the program of Counter-Reformation Christian art has often been overshadowed in scholarship by extensive research into genres typically associated with women in the period such as portraiture, landscape and still life. This thesis newly addresses the sacred artwork of the painter Lavinia Fontana (1552–1614) within the unique context of sixteenth-century Bologna, where the colourful social and intellectual network inspired, endorsed, and influenced her practice. Reassessing Fontana’s sacred images through a contextual framework, I focus on two prominent Bolognese figures: the archbishop Gabriel Paleotti (1522-1597), and the natural historian Ulisse Aldrovandi (1522-1605). Fontana’s sacred paintings follow Paleotti’s post-tridentine art theory by means of her rigorous attention to rendering Scripture clearly and accurately. She may have also enhanced the contemplative possibilities of her images by utilizing her knowledge of natural history. In some cases, paintings by Fontana may call attention to particular flora and fauna species to introduce meaningful symbolism. Upon addressing natural history in Bologna in further detail, it becomes apparent that the Bolognese were highly interested in “New World” knowledge, which undoubtedly had an impact on Italian perception, as well as European Christian art. Scripture, science, and natural history converge in this thesis to shed light on Fontana’s often overlooked religious art practice and what it could have meant to her beholders.


identifier: Sun, Ying  (2018) Heat Extraction System for Augmenting the Heating and Peak Shifting Ability of Electrically Heated Floor Residential Buildings.  Masters thesis, Concordia University.

abstract:
Peak shifting plays a vital role in easing the stress on electrical grids as well as in reducing the electricity bill for consumers by taking benefit of the time-of-use tariff. In cold climates, this can be achieved effectively by storing the heat in thermal energy storage (TES) systems during off-peak periods and releasing the stored heat during peak periods. In this regard, building integrated thermal energy storage (BITES) systems (e.g. ventilated wall, electrically heated floor (EHF) with high thermal mass (e.g. bricks, concrete), hydronic heated floor etc.) can be used. It is worth stating that a well-designed BITES system can completely shift the load from peak periods to other periods. On the other hand, residential buildings in places like North America face practical constraints on incorporating high thermal mass into each envelope and each room. To overcome this limitation and also mainly to increase the percentage of peak load shifting, the present work proposes a forced ventilation system/heat extraction system (HES) to transfer the additional heat from zones with well-designed BITES system to zones with no such provisions.
In this study, a multistory house, in which the BITES system (i.e. EHF) is mainly installed on the basement floor is developed in TRNSYS and validated using the field measurement data. The validated model is then utilized to evaluate the peak shifting potential of the existing EHF under different heating strategies. It is inferred from the simulation results that the existing EHFs almost had the ability to completely shift the heating consumption in the basement from peak period to other periods).  Further, the potential of HES to transfer the heat from the basement to the second floor are investigated in terms of its heating performance (effect of air flow rate and outlet location) and ability to extend the peak shifting potential of EHF. The key finding of the present study is that the HES augments the peak shifting potential of EHF up to 19%.  Also, it is inferred that the proposed methodology increases the heating energy consumption by 18% but decreases the daily heating cost by 24%. It should be mentioned that the increase in energy consumption is due to the prolonged operation of the basement EHF during the off-peak period and the decrease in energy cost is because of shifting the peak to the off-peak period.
The proposed concept would be a benefit to both supplier and consumer in terms of peak shifting and heating cost saving. Also, the proposed methodology resolves the constraint of incorporating higher thermal mass in each floor of the residential buildings.


identifier: Jin, Qiao  (2018) Ego3, a regulator of TORC1 signaling, is degraded by the intralumenal fragment pathway.  Masters thesis, Concordia University.

abstract:
Target of rapamycin complex 1 (TORC1) is a conserved protein kinase complex whose activity controls metabolism in eukaryotic cells.  To function, TORC1 and its regulators are localized to lysosome membranes. The mechanism(s) that control TOR complex protein lifetimes remain enigmatic. The IntraLumenal Fragment (ILF) pathway is a selective protein degradation pathway that involves lysosomes. Thus, I hypothesized that components of TORC1, EGO and SEA complexes may be degraded by this ILF pathway.
Using the yeast S. cerevisiae and its vacuolar lysosome (or vacuole) as models, I tested this hypothesis by first imaging live cells by fluorescence microscopy. I found that several subunits of TORC1, EGO and SEA complexes tagged with GFP are sorted into boundaries between docked vacuoles and accumulate within the vacuole lumen. However, when I isolated vacuoles from cells and repeated this experiment in vitro, I found that nearly all components re-localized to endosomes. The only exception was Ego3, a subunit that tethers the EGO complex to vacuole membranes. I then applied rapamycin, an inhibitor of TOR, to induce TOR protein downregulation and degradation. In vivo, I found that rapamycin stimulated sorting of TOR complex . Whereas, in vitro, rapamycin only enhanced sorting, internalization and degradation of Ego3.
In conclusion, many components of TOR signaling complexes seem to be degraded by the ILF pathway including Ego3. Thus, I speculate that the ILF pathway may play an important role in downregulating TOR activity.


identifier: Wang, Ban ORCID: https://orcid.org/0000-0001-8002-1263 <https://orcid.org/0000-0001-8002-1263>  (2018) Fault Diagnosis and Fault-Tolerant Control of Unmanned Aerial Vehicles.  PhD thesis, Concordia University.

abstract:
With the increasing demand for unmanned aerial vehicles (UAVs) in both military and civilian applications, critical safety issues need to be specially considered in order to make better and wider use of them. UAVs are usually employed to work in hazardous and complex environments, which may seriously threaten the safety and reliability of UAVs. Therefore, the safety and reliability of UAVs are becoming imperative for development of advanced intelligent control systems. The key challenge now is the lack of fully autonomous and reliable control techniques in face of different operation conditions and sophisticated environments. Further development of unmanned aerial vehicle (UAV) control systems is required to be reliable in the presence of system component faults and to be insensitive to model uncertainties and external environmental disturbances.

This thesis research aims to design and develop novel control schemes for UAVs with consideration of all the factors that may threaten their safety and reliability. A novel adaptive sliding mode control (SMC) strategy is proposed to accommodate model uncertainties and actuator faults for an unmanned quadrotor helicopter. Compared with the existing adaptive SMC strategies in the literature, the proposed adaptive scheme can tolerate larger actuator faults without stimulating control chattering due to the use of adaptation parameters in both continuous and discontinuous control parts. Furthermore, a fuzzy logic-based boundary layer and a nonlinear disturbance observer are synthesized to further improve the capability of the designed control scheme for tolerating model uncertainties, actuator faults, and unknown external disturbances while preventing overestimation of the adaptive control parameters and suppressing the control chattering effect. Then, a cost-effective fault estimation scheme with a parallel bank of recurrent neural networks (RNNs) is proposed to accurately estimate actuator fault magnitude and an active fault-tolerant control (FTC) framework is established for a closed-loop quadrotor helicopter system. Finally, a reconfigurable control allocation approach is combined with adaptive SMC to achieve the capability of tolerating complete actuator failures with application to a modified octorotor helicopter. The significance of this proposed control scheme is that the stability of the closed-loop system is theoretically guaranteed in the presence of both single and simultaneous actuator faults.


identifier: Elmasry, Mohamed  (2018) Planning Inspection of Sewer Pipelines Using Defect Based Risk Approach.  PhD thesis, Concordia University.

abstract:
Due to the poor conditions of wastewater networks, there is an increasing need in the capital investments allocated for enhancing their condition. As per the Canadian Infrastructures Report Card, one third of the total lengths of sewer pipes in Canada is in fair to very poor condition (Canadian Infrastructures Report Card, 2016). As such, there is an urgent need for inspection planning tools, with which decision makers could assess the condition of pipelines and identify pipes with higher risk of failure. These tools are potentially of service in prioritizing and optimizing inspection activities that lead to decisions regarding appropriate courses of action, especially in cases of limited resources and funding.
The goal of this research is to develop an optimization model for scheduling the inspection of sewer pipelines by performing defect-based risk assessment. The risk of failure is determined to identify critical pipe sections; by combining likelihood and consequence of failure values using
the Sugeno Fuzzy Inference System. The developed optimization model determines the inspection sequence of pipeline sections in addition to optimizing the utilization of inspection crews by minimizing both time and cost of inspections. The risk assessment model is divided into two sub
models: likelihood and consequences of failure. Structural and operational defects and pipeline characteristics in an existing sewage network are used to develop the likelihood model that
determines the structural, operational and overall condition ratings of pipelines.
Method-wise, Bayesian Belief Network (BBN) is used to develop a static condition assessment model using probabilities of occurrences and conditional probabilities. Moreover, time dimension is introduced to the developed BBN model using logistic regression as temporal links
which are required to convert BBN into Dynamic Bayesian Network (DBN). The accuracy of the model’s prediction is examined through referencing of actual data, where the Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) for the BBN model are 0.67, 1.06, 0.56 and 1.05, 1.60, 0.95 for structural, operational and overall conditions, respectively.  The second sub-model representing the consequences of failure is developed to determine the impact of sewer pipelines’ failure using Cost Benefit Analysis (CBA). Developing this sub model involves identifying and analyzing costs of failure and benefits resulting from avoiding such failures. In order to validate the CBA model, actual costs from a real failure incident are compared
with the proposed model's outputs. During the implementation of the CBA model, it is found that the indirect costs resulting from sewer pipelines’ failure represent a significant portion of the total failure costs.
The proposed risk assessment model is validated using actual data derived from inspected sewer pipelines. Cost savings of around 67% could be achieved if the risk assessment model is applied and deployed over ongoing inspection practices followed by municipalities. A Mixed Integer Linear Programming (MILP) model is developed to optimize scheduling of inspection activities by including sewer sections, time and cost of inspections. This model is developed using GAMS and solved using CPLEX to maximize the number of sections and minimize time and cost.
The output from the MILP model is compared to the results of another model solved using the Genetic Algorithm (GA) approach. It is found that the MILP model could perform better than the GA model in terms of optimal solutions. Additionally, a resulting inspection cost reduction of approximately 38% could be achieved when utilizing the MILP model. It is expected that the proposed inspection scheduling model could help decision makers
better assess the condition of sewer pipelines and improve their decision-making on proactive or reactive measures. The proposed model could help allocate budgets more efficiently in addition, to being an enabler for better inspection programs, particularly in cases of limited funds and task forces.


identifier: Novakova, Lenka  (2018) The Scenographic Unfolding: Performance of Immersive, Interactive and Participatory Environments.  PhD thesis, Concordia University.

abstract:
Performance in theatre, as well as in certain forms of visual arts (such as happenings, performance art, etc.), has for the most part been understood as an action of a live performer in front of an audience while space / scenography has typically been conceived of as that which provides a certain atmosphere for or otherwise supports this said performance.  This dissertation sets out to explore yet another way of thinking about performance: the performance of space itself, emerging from within a dialogue between theatre and visual arts as a scenographic unfolding.
Insisting that material / technological mediation and transformation of body / space relationships is key in thinking about performance at the intersection of installation art (in visual arts) and expanded scenography (in theatre), this present research employs practice itself in the exploration of performance as scenographic unfolding in environments that are immersive, interactive and participatory. In so doing, this study seeks to shed light on how the established definitions of immersion, interaction and participation, as terminologies entangled between the visual arts and theatre, may be reconfigured through practice. Hence, this research aims to fill a gap by highlighting how practice elucidates this mediation and transformation of spatial performance at the intersection of visual arts and theatre.


identifier: Friedland, Eli  (2018) A Footnote to Plato: Human Nature and Character in the Laws.  PhD thesis, Concordia University.

abstract: This dissertation argues that Plato makes a crucial and still-pertinent distinction, in the Laws, between genuine responsibility and political responsibility, and that that distinction can only emerge from a close engagement with the characters crafted by him. I propose, and defend in detail, that the character of Megillos, in Plato's Laws, can be seen on close consideration to lean profoundly toward the philosophic life, despite and because of the image of the typical or even particularly obtuse citizen that he deliberately presents himself as. How he comports himself, and why, is an indication in the Laws of genuine responsibility as a way of life that requires neither political recognition nor political reward. That Megillos shares this way of life with the Athenian Stranger – often taken to be the philosophical character in the Laws – is, I show, key to Plato’s teaching on taking responsibility for the laws. Conversely the character of Kleinias – the Cretan statesman in the Laws – reveals a disposition that is far more dependent on such recognition and reward than the character himself realizes, a character whose very belief in his own independent responsibility disguises, to himself, his deep reliance on and affinities with the people he considers his inferiors. I first bring these understandings of the Laws’ characters to an examination of the general conflicts between the demands of necessity as they impose themselves on the Stranger and Megillos, and as they appear to Kleinias in the form of moral and political righteousness. Following this, I closely consider Plato’s teaching on natural and conventional right as it emerges in the controversial discussion of sexuality, and particularly homosexuality, in Book 8 of the Laws. That discussion comes into a profoundly different light when the ramifications of character are brought to bear upon it, than it does when taken as a simple statement of Plato’s “beliefs”. The strange image of animal desire and self-control is presented most forcefully there by the Stranger to Kleinias as a seeming standard of natural right, and seems to present homosexuality (and all extramarital liaisons) as “against nature”. Upon closer consideration, however, that image turns out to be at odds not only with “the nature of beasts” that it presents as its foundation, and not only with the very human psychology to which it seems intended to appeal (through a sense of honor), but also – indeed especially – with the philosophical “Socratic” eros that the Stranger and Megillos (though not Kleinias) agree is the highest human eros, and which is even presented as the most desirable eros politically. The Stranger’s hesitancy or refusal to speak of his image as simply true emerges as a pregnant hesitancy, as a deliberate and successful attempt to speak separately with Megillos about the severe limits of human voluntariness even as he urges Kleinias to celebrate voluntariness as a capacity that only the dishonorable would fail to exercise. In having that conversation, the Stranger and Megillos do responsibility, and responsibly leave intact Kleinias’ (and the city’s) own image of political responsibility as genuine.


identifier: McAuley, Melissa  (2018) Effects of Novel Aging-Delaying Plant Extracts on the Lipid Composition of the Yeast Saccharomyces Cerevisiae.  Masters thesis, Concordia University.

abstract:
A collaboration between the Titorenko laboratory and Idunn Technologies Inc. has led to a recent discovery of 14 plant extracts that delay the chronological mode of aging in the budding yeast Saccharomyces cerevisiae. Age-related changes in the abundance of lipid droplets, a site for the deposition and lipolytic degradation of the neutral lipids triacylglycerols and steryl esters, are known to play essential roles in defining yeast longevity. Therefore, one objective of my thesis was to investigate how each of the 14 aging-delaying plant extracts influences the number and size of lipid droplets at different stages of yeast chronological aging. I found that 8 of 14 plant extracts delay yeast chronological aging not because they alter the number of droplets or change their size. Because the number and size of lipid droplets are known to be defined by the relative rates of neutral lipid synthesis in the endoplasmic reticulum, neutral lipid deposition in lipid droplets, neutral lipid lipolytic degradation in lipid droplets, fusion of lipid droplets and fragmentation of lipid droplets, I concluded that the aging-delaying effects of these 8 plant extracts in yeast are unlikely to be caused by changes in the relative rates of the above cellular processes. I also found that 6 of 14 aging-delaying plant extracts cause changes in the number or size of lipid droplets only on one or two (out of four) days of cell collection, each corresponding to different stages of the aging process. These findings suggest that such changes in lipid droplets abundance may (or may not) play essential roles in the ability of some (or all) of these 6 plant extracts to delay yeast chronological aging. To address this, further experiments are required. Because the synthesis,
iv
storage and degradation of neutral lipids are integrated into metabolic pathways for other lipid classes, I then used a combination of liquid chromatography and mass spectrometry to examine how 2 of the aging-delaying plant extracts that increase the size of lipid droplets without affecting their number affect the intracellular concentrations of several classes of lipids in chronologically aging S. cerevisiae. I found that these 2 aging-delaying plant extracts exhibit different and statistically significant effects on the concentrations of phosphatidylinositol phospholipids, triacylglycerols and free fatty acids. I therefore concluded that there may be 2 different ways of remodeling lipid metabolism in response to 2 different aging-delaying plant extracts. Future studies will test if such specific remodeling of lipid metabolism plays a causal role in the ability of each of these plant extracts to delay chronological aging of S. cerevisiae.


identifier: Ale ebrahim, Elnazsadat  (2018) Fabrication of Ceramic Filtration Membrane Using Suspension Plasma Spray Process.  Masters thesis, Concordia University.

abstract:
Suspension plasma spraying (SPS) is an emerging versatile and scalable coating technology for deposition of sub-micron sized particles on different substrates to generate coatings with fine microstructures and high mechanical and physical properties. This work, was the first attempt to fabricate ceramic filtration membrane with SPS technique.
Porous pressure driven ceramic filtration membranes with asymmetric micro structures are effective tools for removing pollutants in many industries. Depending on the contaminants of concern, submicron to a few micron-sized pores are essential for this application. Suspension plasma spray enables deposition of a few microns to nano-sized particles to generate such a microstructure. Titanium dioxide membrane has gained interest as water treatment filter due to its mechanical, chemical and thermal stability, its nontoxicity, availability and photocatalytic property.
The promising results of this study confirmed the potential of suspension plasma spray technique as an emerging process in ceramic membrane manufacturing. Porous water permeable titanium dioxide membrane with 14% of open porosity and considerable water flux was produced, in which the network of open pores was generated by accumulation of un-melted and re-solidified particles. In addition, SPS titanium dioxide membrane exhibited photocatalytic property.


identifier: Esmaeilzadeh, Sahar  (2018) Application of Agent-Based Modeling in Multi-Source Biomass Supply Chain Purchase Planning and Scheduling for a Power Plant.  Masters thesis, Concordia University.

abstract:
Renewable energies play a pivotal role in social, political and environmental affairs of every country. Numerous reports state that among all the renewable options, biomass is one of the most sustainable alternatives. However, biomass-fired energy plants face several unintended potential consequences. The cost and risk burden on facility managers is an issue given the lack of historical data on life-cycle operation and maintenance of technologies.
With the advancement of computational capabilities, Agent-Based Modeling and Simulation (ABMS) is rapidly replacing conventional simulation techniques. Creating a successful simulation model can support the enhancement of logistical efficiency. The most common simulation technique used in biomass supply chain management is System Dynamics (SD). SD modeling in nature is highly abstract and therefore inadequate to consider the complete biomass supply chain structure and all related detail and information.
Agent-Based Modeling and Simulation (ABMS) can act as an add-on to complement SD simulation method. In this thesis, the fundamentals of ABMS are combined with SD simulation technique in order to overcome many limitations of current modeling and simulation practices. ABMS is a bottom-up modeling techniques where actors and participants of the system are given attributes and their behavior is encoded as a set of rules. Currently the applications of ABMS in biomass supply chain management is limited and few in numbers, however, this technique is gaining the interest of many specially in the field related to supply chain management.
A simulation model for the process of biomass purchase scheduling, planning and management for a power plant is developed. The model establishes a holistic approach in absence of knowledge of BSC system’s behavior and provides a reusable base that facilitates modeling various scenarios and measuring their performance through simulation. To address the challenges, four different scenarios have been designed and implemented. First scenario analyzes the outputs of the system in case of an increase in the scale of the operation. In the second scenario, the acceptable biomass types have been limited to only woody and high quality types. In the third scenario, storage method has been improved and combined with hot air treatment method. As for the forth scenario, ambient storage method as the cheapest method with high deterioration rate has been investigated. The results of these scenarios have been reported and individually evaluated. By conducting a comparison analysis between these scenarios and the base scenario, their advantages and disadvantages have been assessed. The third scenario is identified as the most favorable.


identifier: Doerksen, Mark  (2018) How to make sense: Sensory modification in grinder subculture.  PhD thesis, Concordia University.

abstract:
This doctoral research examines the Canadian and American grinder scenes to gain insight into the role of senses in understanding and responding to social problems. Grinders, a subset of biohackers, aim to enhance themselves by assimilating emerging material technologies (including, but not limited to, electronics) with their bodies through experiments and surgeries. They opt for a do-it-yourself (DIY) approach in order to maintain a sense of agency that might be lost if pursued through traditional means, such as ‘normalized’ medical research, ethically constrained university research, or market-driven private industry. How do grinders make sense (literally and figuratively) of their bodies as a site for enhancement?

The research design included three years of virtual ethnography of online grinder hubs, which were connected and contrasted with a concurrent two years of ‘real world’ participant observation ethnography at grinder laboratories and events. Data analysis applied actor-network theory to trace grinders’ sensory assemblages through a variety of on- and off-line sources.  These included internet forum posts, IRC chat logs, and blogs, as well as 40 in-depth interviews, dozens of informal interviews, and direct observations of grinders planning, surgically implanting, and using their ‘enhancements.’ Results demonstrated how grinders position their bodies both broadly in relation to their current social circumstances, as well as specifically through three case studies involving magnetic implants, RFID tags, and body-computer interfaces.

This study is situated in Cyborg Anthropology and Science and Technology Studies to understand the relationship between bodies, technology, and culture. Findings suggest grinders conceive of the human body as an ironic hybrid of positivism and constructionism, determined by its techno-biological material yet simultaneously amenable to endless modification. In practice, however, the results of the tension between stability and variability tend to reinforce hegemonic social and economic relationships. What grinders ultimately enhance is the ability to adapt their physical bodies to social uncertainty brought about by the accelerating digital economy of information.


identifier: Akbari Choubar, Mohammad  (2018) Performance Enhancement of Radiation and Scattering Properties of Circularly Polarized Antennas Using Frequency Selective Surface.  PhD thesis, Concordia University.

abstract:
At millimetre-wave (MMW) frequencies, losses associated with wireless link and system are critical issues that need to be overcome in designing high-performance wireless systems. To compensate the overall loss in a wireless communication system, a high-gain antenna is required. Circularly polarized (CP) antennas are among preferred choices to design because they offer many advantages due to their good resistance to polarization mismatch, mitigation of multipath effects, and some phasing issues and immunity to Faraday rotation. On the other hand, frequency selective surface (FSS) technology is recently employed to enhance the performance of radiation and scattering properties of antennas used in different sectors such as aerospace, medical, and microwave industry. Therefore, it is appropriate and attractive to propose the use of FSS technology to design practical and efficient CP antennas.
CP Fabry-Perot cavity (FPC) antennas based on FSS are investigated in this thesis to fulfil the growing demand for broadband high-gain antennas with low radar cross section (RCS). The thesis investigates both characteristic improvement of CP antennas and RCS reduction issues employing FSS structures.
Initially, a high gain CP dielectric resonator (DR) antenna is proposed. Using an FSS superstrate layer, a gain enhancement of 8.5 dB is achieved. A detailed theoretical analysis along with different models are presented and used to optimize the superstrate size and the air gap height between the antenna and superstrate layer.
The second research theme focusses on developing an effective approach for mitigating the near-field coupling between four-port CP antennas in a Multiple-Input, Multiple-Output (MIMO) system. This is obtained by incorporating a two-layer transmission-type FSS superstrate based on planar crossed-dipole metal strips. Another technique for suppressing the spatially coupling
between DR antennas using a new FSS polarization-rotator wall is studied as well. The coupling reduction is achieved by embedding an FSS wall between two DRAs, which are placed in the H-plane. Utilizing this FSS wall, the TE modes of the antennas become orthogonal, which reduces the spatially coupling between the two DRAs.
The third research theme of this thesis is to enhance the purity and bandwidth of CP with the least amount of insertion loss by the use of an LP-to-CP-polarizer which is based on multilayer FSS slab. This polarizer is approximately robust under oblique illuminations. To have a high-gain CP antenna, an 8-element LP array antenna with Chebyshev tapered distribution is designed and integrated with the polarizer.
Eventually, in order to enhance the scattering property, the fourth research theme investigates on RCS reduction by the use of two different approaches which are based on FSS. Initially, a wideband FSS metasurface for RCS reduction based on a polarization conversion is proposed. To distribute the scattered EM waves and suppress the maximum bistatic RCS of the metasurface over a broad band of incident angles at both polarizations, the elements are arranged using the binary coding matrix achieved by group search optimization (GSO) algorithm. The reflective two-layer metasurface is designed in such a way to generate reflection phase difference of 180° between two elements “0” and “1” on a broad frequency band. A theoretical analysis is performed on the ratio of the “0” and “1” elements using Least Square Error (LSE) method to find the best ratio value. As the second activity of this research theme, wideband CP antenna with low RCS and high gain properties is presented. The proposed antenna is based on a combination of the FPC and sequential feeding technique.


identifier: Isidori, Agustina  (2018) A Research-Creation Approach to Gender-Based Violence.  Masters thesis, Concordia University.

abstract: My research and creative work critically engage with gender-based violence, paying special attention to the extreme case of feminicide/femicide. Gender-based violence is an endemic problem found equally across the private and the public sphere. Feminicide/femicide is the most extreme expression of gender-based violence. It is the last link of a long chain of violence entrenched in the mindset of a patriarchal and capitalist system. In this system, the body is perceived as an exploitable and disposable commodity. This thesis reflects on the layered process that led me to the completion of two pieces emerging from a research-creation approach. This process involved an in-depth research, prototyping and iterative work, followed by exhibitions and reflections. My research is informed by concepts related to the treatment of violence and suffering through cultural expressions. During the design process, I gained insight regarding the complexities of dealing with delicate topics. In response to the many levels of complexity embedded in this subject matter, my creative practice focused on an iterative process in which a corpus of work was created. While each piece can function independently, they are tied to the same research. Through these iterations, I unfold diverse strategies that may be useful for future artists and designers working with gender-based violence.


identifier: Ajayi, Olumayowa Francis  (2018) Translation and National Consciousness in Nigeria: A Socio-historical Study.  PhD thesis, Concordia University.

abstract:
Interdisciplinary in orientation, this study draws knowledge from the fields of Translation Studies, History and Political Science in a bid to explore the interplay between translation and nationalism in a sub-Saharan African context. More specifically, the current research focuses on the Nigerian experience of nationhood and seeks to investigate the effect(s) of translation on the construction of a psychological notion of nationalism that aligns with the concept of the nation as an imagined community. The research upon which this study rests makes use of the socio-historical approach to translation theory and practice, which privileges such questions as: what was translated, by whom and in what social and political contexts.
The findings point to the existence of several notions and experiences of translation that are specific to oralate communities, and further buttress the argument that Western conventions, despite their major contributions to knowledge, do not sufficiently account for the cultural sensibilities that animate the practice of translation in national contexts that boast a robust historical and ongoing relationship with orality.
What’s more, the current study reveals the roles played by precolonial translation practices in the sustenance of the prevailing religious and cultural traditions, which in turn helped corral the precolonial nation’s inhabitants into a non-coerced form of social conformity and consciousness. Translation would subsequently replace the precolonial model of nationhood with a national imagination that was steeped in British colonial paradigms and fashioned to meet the ends of colonial nationalism. In the Nigerian postcolony, the role of translation in fashioning an anti-imperialist literary discourse as well as the production of fictional representations of contemporary social realities has spurred “national texts,” which have not only resonated within the consciousnesses of the nation’s diverse peoples, but have also inspired them to think of themselves as members of the same community. This sense of community has, however, been fraught with myriad problems, such as translation’s involvement in the consolidation and promotion of the Northern reality of Islamic fundamentalism and conservatism, which has, over the centuries, pulled most of the inhabitants of the Northern half of the nation-space into a regional sub-culture that is buoyed by ideological forces operating out of the Arabian peninsula. Translation has therefore facilitated a conflicting experience of nationhood in the contemporary nation-space that is deeply rooted in a historical legacy of religious and cultural alterity.


identifier: Amarica, Sarah  (2018) Working Bodies, Poignant Cloth: Materialising Histories of Labour in Ann Hamilton’s indigo blue (1991, 2007) and Ibrahim Mahama’s Occupations (2012–).  Masters thesis, Concordia University.

abstract: American artist Ann Hamilton (b. 1956) once described her country’s history as being guilty of the erasure of labouring bodies, and, like Ghanaian artist Ibrahim Mahama (b.1987), she uses textiles in her installation art to poignantly reflect on histories of labour. This thesis addresses the critical connections between labour, capital, and contemporary material practices by examining Hamilton’s indigo blue (1991, 2007) and Mahama’s ongoing Occupations series (2012–), both of which utilise cloth to unearth the histories of labour in their home countries. Hamilton’s artwork comprises 6,000 kilograms of blue-collar clothing stacked into a colossal heap and reflects on the history of indigo and cotton production in the American South, and the slave labour that sustained these industries for centuries. Mahama’s work reconfigures old jute sacks, used to transport coal and cocoa in Ghana, into vast patchwork panels, then drapes them across buildings worldwide to manifest the labour behind these industries and the global demand that sustains them. Structured around these case studies and drawing primarily from material culture discourse, this inquiry negotiates the stories behind things produced, the human bodies behind globally-consumed commodities, and ultimately, the manifestation of these discussions through cloth. There is significant value in comparing Hamilton and Mahama’s artworks, not only because in both cases commodity production can be linked with socioeconomic conditions (of the United States and Ghana respectively) but because their art practices implicitly advocate for the role that contemporary artists may play in critically examining labour, past and present.


identifier: Garmeh, Saeed  (2019) Transportation of high concentration suspension using visco-plastic lubrication.  Masters thesis, Concordia University.

abstract: Surface engineering plays an important role in different industries. Enhancing the surface properties while keeping the base material properties is the ultimate goal of surface engineering. If the coating is manufactured by melting the particles with heat, it is called thermal spraying. Suspension plasma spraying (SPS) is a branch of thermal spraying where the coating material is suspended in a base liquid. The suspension is injected to a plasma that melts the particles. These molten particles strike the substrate, solidify and form the coating. One of the main challenges in SPS is clogging the suspension in the feeding line. Interaction of the particles with the tube wall may result in sedimentation (fouling) and reduction in the passing area through the tube and finally blockage of the suspension flow. In this case, the spraying process should be stopped and further actions need to be taken for cleaning the suspension line and the injector. The other challenge is the speed of the spraying. SPS is considered as a slow process compared to other conventional thermal spraying methods. Typically, suspensions have concentration of about 10-25 wt. % which means only 10-25 % of the total mass of suspension is made of the particles that actually contribute to the coating. In this study, visco-plastic lubrication is introduced to avoid clogging while increasing the concentration of the suspension up to 70 wt. %. The key element in visco-plastic lubrication is utilizing a yield stress fluid as the lubricant. Yield stress materials behave like fluids if they are submitted to a stress higher than a threshold called yield stress. If the stress is less than that, they behave like solids. In visco-plastic lubrication, a solid protective layer around the core fluid is formed that keeps the core fluid at the center and does not let it touch the tube wall. In this combined experimental and numerical study, the conditions to establish a stable core-annular flow of suspension-yield stress fluids were determined to transport high concentration suspensions.


identifier: Lajeunesse, Marc  (2018) “It taught me to hate them all.”: Toxicity through DOTA 2’s Players, Systems, and Media Dispositive.  Masters thesis, Concordia University.

abstract:
‘Toxicity’ has become a pervasive term for describing and discussing online game communities,but exactly what constitutes toxicity remains loosely defined. This project seeks to uncover how toxicity is constructed and understood within a game community described from inside and out as toxic.
After situating toxicity within prior academic literature on toxicity’s constitutive elements such as griefing, trolling, flaming and racism online, this project focuses on the DOTA 2 community. It
examines how the game’s culture operates throughout what Mirko Tobias Schäfer referred to as the media dispositive, or the collection of sites and discourses that the community engages with that overlap with the in-game experience. Throughout the dispositive certain voices are sanctioned by the game’s company, Valve, while others are silenced by the affordances of the dispositive’s sites and game’s culture.
The final section of this work explores the in-game experience through ethnographic, interview, and participant observation data, to uncover how players perceive toxicity in-game. This work finds that toxicity is in part reflective of and formed by the broader culture of the game as discovered through an analysis of the dispositive, but that players possess highly subjective ideas about what constitutes toxicity that they tend to universalize, which strengthens toxicity as a rhetorical rather than descriptive term. The impact of toxicity on players and community members is uneven as some players are put into conflict with others while others, particularly women, are erased from the game space and community discussions. In conclusion, this project finds that toxicity in DOTA 2 is constructed by overlapping cultural and mechanical elements and is as much about what players perceive to be toxic as
it is about actual player behaviors.


identifier: Jalbert, Élie  (2018) Where Power Comes to Matter: The Energy East Pipeline and the Politics of Determinacy.  Masters thesis, Concordia University.

abstract:
This thesis is about the controversies that engulfed TransCanada's Energy East pipeline project from the moment it emerged into the public sphere in 2013, and which led to its ultimate demise in 2017. As such, it is an investigation into how power, sovereignty, and agency were mobilized in the negotiation of a pipeline project in Canada. In the contemporary political and environmental climate, pipeline projects have had a rough go of it. Sweeping changes made to the legislative and regulatory framework by the Conservative federal government in 2012 were intended to expedite their approval but appear to have had a contrary effect. Rather than provide certainty to proponents, the changes further undermined the decisional infrastructure and distribution of constitutional authority. In this context, the contest has been less about substantive deliberation than infrastructural determination, as normative decisional frameworks became further unsettled. The controversy opened up a wide range of questions, such as: Who had power to decide? Which jurisdictions applied? How should democratic participation be delineated? Who was the public that the regulator purportedly spoke for? How were decisions justified? What counted as evidence?  In other words, it was as much about which projects might be considered as being in the "national" interest as it was about the procedural and epistemological channels through which this determination should be made.
My observation has been that stuck between growth imperatives, vested interests, democratic expectations, and a growing recognition of impending environmental crisis, governments and companies like TransCanada prefer determinate power relations: a clear and exclusive allocation of decision-making authority. They also prefer indeterminate substantive guidelines, writing as much discretionary power into the law as possible and leaving open the possibility of strict environmental protections in general while allowing for exceptions in the specific. Environmental assessment reformists, on the other hand, prefer indeterminate power — a shared and inclusive distribution of decision-making power — and determinate substantive legal guidelines. What substantive indeterminacy combined with centralized, exclusive power makes possible is framing contingent transgressions of overall political goals as exceptional. In the controversy over TransCanada’s pipeline project, the public was not just pushing back against oil and its potentially devastating effects. They were also pushing back against a regulatory infrastructure which evacuated too much of its political agency and normalized the particular interests of some as the inevitable future for all.


identifier: Davar, Somayeh  (2018) Ternary and Hybrid Event-based Particle Filtering for Distributed State Estimation in Cyber-Physical Systems.  Masters thesis, Concordia University.

abstract: The thesis is motivated by recent advancements and developments in large, distributed, autonomous, and self-aware Cyber-Physical Systems (CPSs), which are emerging engineering systems with integrated processing, control, and communication capabilities. Efficient usage of available resources (communication,computation, bandwidth, and energy) is a pre-requisite for productive operation of CPSs, where security, privacy, and/or power considerations limit the number of information transfers between neighbouring sensors. In this regard, the focus of the thesis is on information acquisition, state estimation, and learning in the context of CPSs by adopting an Event-based Estimation (EBE) strategy, where information transfer is performed only in the occurrence of specific events identified via the localized triggering mechanisms. In particular, the thesis aims to address the following identified drawbacks of the existing EBE methodologies: (i) At one hand, while EBE using Gaussian-based approximations of the event-triggered posterior has been fairly investigated, application of non-linear, non-Gaussian filtering using particle filters is still in its infancy, and; (ii) On the other hand, the common assumption in the existing EBE strategies is having a binary (idle and event) decision process where during idle epochs, the sensor holds on to its local measurements while during the event epochs measurement communication happens. Although the binary event-based transfer of measurements potentially reduces the communication overhead, still communicating raw measurements during all the event instances could be very costly. To address the aforementioned shortcomings of existing EBE methodologies, first, an intuitively pleasing event-based particle filtering (EBPF) framework is proposed for centralized, hierarchical, and distributed (iii)state estimation architectures. Furthermore, a novel ternary event-triggering framework, referred to as the TEB-PF, is proposed by introducing the ternary event-triggering (TET) mechanism coupled with a non-Gaussian fusion strategy that jointly incorporates hybrid measurements within the particle filtering framework. Instead of using binary decision criteria, the proposed TET mechanism uses three local decision cases resulting in set-valued, quantized, and point-valued measurements. Due to a joint utilization of quantized and set-valued measurements in addition to the point-valued ones, the proposed TEB-PF simultaneously reduces the communication overhead, in comparison to its binary triggering counterparts, while also improves the estimation accuracy especially in low communication rates.


identifier: Alotaibi, Khalid Saqer S ORCID: https://orcid.org/0000-0002-0274-4922 <https://orcid.org/0000-0002-0274-4922>  (2018) Axial-Flexural Behaviour of Reinforced Concrete Masonry Columns Confined by FRP Jackets.  PhD thesis, Concordia University.

abstract: Confining existing concrete and masonry columns by Fibre Reinforced Polymers (FRP) is a beneficial method for enhancing the column capacity and ductility. The popularity of using FRP for strengthening and upgrading columns is mainly attributed to the high strength and lightweight characteristics of the FRP materials. Using FRP composites reduces additional dead load associated with traditional strengthening solutions and simplify the application in areas with limited access. The goal of this research is to experimentally quantify the enhancement in strength and strain capacity of Carbon FRP (CFRP) confined concrete masonry columns under concentric and eccentric loading. Research on FRP-strengthened concrete masonry columns under eccentric loads is essential to understand the effect of this retrofitting technique on the performance of columns. The experimental data was then used to propose a simplified methodology that predicts the axial force-moment interaction diagram of fully grouted reinforced concrete masonry column strengthened with FRP jackets. The methodology considers short prismatic reinforced concrete masonry columns failing in a compression controlled manner and complies with equilibrium and strain compatibility principles. To achieve the research goals, 47 scaled fully grouted concrete block masonry columns were tested under concentric, eccentric, and bending loading up to failure. Parameters investigated in this research include the thickness of CFRP jacket, corner radius of cross section and the magnitude of eccentricity. The proposed analytical methodology showed a good correlation with the experimental data. Parametric study was carried out to determine the effect of design variables on the axial-flexural interaction of fully grouted reinforced concrete masonry column strengthened by FRP jackets.


identifier: Esmaeilpour, Milad  (2018) A Novel Approach to Transmission Power, Lifetime and Connectivity Optimization in Asymmetric Networks.  Masters thesis, Concordia University.

abstract: This thesis deals with the problem of proper power management over asymmetric networks represented by weighted directed graphs (digraphs) in the presence of various constraints. Three different problems are investigated in this study. First, the problem of total transmission power optimization and connectivity control over the network is examined. The notion of generalized algebraic connectivity (GAC), used as a network connectivity measure, is formulated as an implicit function of the nodes' transmission powers. An optimization problem is then presented to minimize the total transmission power of the network while considering constraints on the values of the GAC and the individual transmission power levels. The problem of network lifetime maximization and connectivity control is investigated afterwards. Each node is assumed to deplete its battery linearly with respect to the transmission powers used for communication, and the network lifetime is defined as the minimum lifetime over all nodes. Finally, it is desired to maximize the connectivity level of the network with constraints on the total transmission power of the network and the individual transmission powers. The interior point and the mixed interior point-exterior point methods are utilized to transform these constrained optimization problems into sequential optimization problems. Given the new formulation, each subproblem is then solved numerically via the subgradient method with backtracking line search. A distributed version of the algorithm, taking into account the estimation of global quantities, is provided. The asymptotic convergence of the proposed centralized and distributed algorithms is demonstrated analytically, and their effectiveness is verified by simulations.


identifier: Modafferi, Daniel  (2018) The Interaction of Tetryl, a Nitroaromatic Explosive, with Bacterial Reaction Centres.  Masters thesis, Concordia University.

abstract:
Tetryl, a nitroaromatic compound, was found to interact in two different measurable ways with bacterial reaction centre protein (BRC). The protein amplifies the reaction of tetryl occurring in the presence of detergent, producing a visible product with absorption peaks at 345 nm and 415 nm. BRC provides a location in the micelle with a rate 80-fold faster than in buffer with equal detergent concentration, and a location in the carotenoid binding site when carotenoid is absent with a rate 400-fold faster than in the bulk.  The tetryl or its reaction product was also found to bind to the BRC near the bacteriochlorophyll dimer with micromolar level dissociation constant. The binding resulted in slowing down the charge recombination kinetics by modifying the light-induced structural changes. Up to 70% of the protein population can be made to recover with a rate constant of 0.01 s-1, about 100-fold slower than in the dark-adapted conformation.
Both these effects can be combined to design a bimodal biosensor. The change in absorbance at 350 nm can be used to detect tetryl in the ppb (parts-per-billion) concentration range, and photocurrents across a monolayer of BRC on an electrode could be affected by the presence of tetryl. Last, this interaction could be the starting point to the design of bio-hybrid charge-storage devices or completely artificial photosynthetic devices.


identifier: Ghaheri, Ehsan  (2018) Limited Lookahead Supervisory Control with Buffering in Discrete Event Systems.  Masters thesis, Concordia University.

abstract:
The Supervisory Control Theory (SCT) of Discrete Event Systems (DES) provides systematic approaches for designing control command sequences for plants that can be modeled as DES. The design is done "offline" (before supervisor becomes operational) and is based on the plant and design specification DES models. These models are typically large, resulting in DES supervisors that require large computer memory - often unavailable in embedded mobile systems such as space vehicles. An alternative is to use the Limited Lookahead Policies (LLP) in which only models of individual plant components and specifications are stored (which take far less memory). The supervisory control command sequences are then calculated "online" during plant operation. In this way, "online" memory requirement can be reduced at the expense of higher "online" computational operations.
In this thesis, the implementation issues of LLP supervisors are studied. The design of LLP supervisors is based on assumptions some of which may not hold in practice. Notably it is assumed that after every event, the supervisory control command can be calculated and applied before the next event occurs. This assumption usually does not hold. To address this issue, a novel technique is proposed in which supervisory control commands are calculated in advance (and online) for a predefined window of events in the future and buffered. When the window starts, the commands would be ready after each event. This eliminates the delay due to online calculations and reduces the delay in responding to new events to levels close to those of standard supervisors (designed "offline").
In an effort to assess the proposed methodology and better understand the implementation issues of SCT, a two degree-of-freedom solar tracker with two servo motors is selected as the plant. Previously, a standard supervisor had been designed for this solar tracker to guide the tracker and perform a sweep to find a sufficiently bright direction to charge the battery and other parts of the system (from its Photo Voltaic cell).
The design of the standard supervisor and its software implementation is improved and polished in this thesis. Next the LLP with buffering is implemented. Several experimental results confirm that the plant under the supervision of LLP supervisor with buffering can match the behavior of the plant under the supervision of standard supervisor.


identifier: Aljehaimi, Akrem Mohamed  (2018) A Rotor Flux Linkage Estimator and Operating Envelopes of a Variable-Flux IPM Synchronous Machine.  PhD thesis, Concordia University.

abstract:
Interior permanent magnet synchronous machines (IPMSMs) with rare-earth magnets are widely used by the electric and hybrid electric vehicle industry due to their high efficiency and high torque density. The drawbacks of the IPMSMs like the fluctuating prices of the rare-earth permanent magnets (PMs), the difficulty in flux weakening, and relatively low efficiency in the high-speed region, triggered the need for alternative electrical machines for traction applications. The variable-flux type IPMSMs, also called memory motors, is a promising technology for electrified transportation applications. These machines make use of low-coercivity magnets such as AlNiCo magnets, which makes them rare-earth PM independent.   Moreover, owing to the low-coercivity, the AlNiCo magnets can be demagnetized in the high-speed region. This reduces or eliminates the extra current component needed for flux weakening, which results in lower copper/iron losses and improved machine efficiency. Besides, the variable-flux IPMSMs can provide torque densities comparable to rare-earth IPMSMs in high-torque low-speed regions.
Since the magnetization state of AlNiCo magnets can be varied online by a short stator current pulse, and the current needed for a particular magnetization state is machine parameter dependent, it is of a vital importance to the drive system to keep track of the magnet flux during transient and steady-state conditions. Moreover, failing in depicting the actual magnetization state of the magnets means a mismatch between the real value of the magnet flux in the machine and the estimated one in the controller, which directly affects the resultant torque and performance. In addition, the current pulse excitation method for magnetization causes non-uniform variable flux distribution in the air-gap. Therefore, an estimation algorithm of the rotor flux linkage of variable-flux IPMSMs via flux harmonics extraction has been proposed. Compared to the existing methods, this method does not need any voltage or current signal injection into the stator winding. The algorithm was experimentally evaluated for different magnetization states and showed a good performance in tracking the rotor flux linkage variations during transient and steady-state conditions
The operating envelopes of the variable-flux IPMSM were found to be affected by the nonlinearity of the magnet flux with the machine direct axis current. New analytical solutions for the operating point were reached for maximum power and maximum output voltage control for the variable-flux IPMSM taking into consideration this nonlinearity. The experimental measurement performed also support the analytical results.
The irreversible demagnetization of the low-coercivity magnets in the high-speed region results in extending the braking time of the variable-flux IPMSMs. A simple yet effective minimal-time braking algorithm is proposed and experimentally validated.


identifier: Buss, Larissa  (2018) L2 Speaking at the University: Naturalistic Changes, Rater Judgments, and Teacher Training.  PhD thesis, Concordia University.

abstract:
This dissertation explores issues related to the development and evaluation of second language (L2) oral performance and to teacher training in L2 pronunciation pedagogy. Study 1 investigated naturalistic changes in L2 graduate student presentations given at the beginning and end of the students’ first two terms of study at an English-medium university. The presentations were evaluated for accentedness, comprehensibility, fluency, topic structure clarity, and overall quality by native English listeners. Links between the listener evaluations and the speakers’ use of paratones (measured as pitch increase at topic shifts) were also explored. The participants became significantly less accented and more comprehensible, but no other changes were found, and pitch increase values were not correlated with any of the listener ratings. Listener comments provided more intricate insights into the role of intonation in perceptions of structural clarity and overall quality of L2 presentations.
Study 2 involved participants from the same pool as those in Study 1, but examined longitudinal changes over four time points. Samples taken from L2 graduate student presentations mostly in engineering and computer science were evaluated for accentedness, comprehensibility, fluency, content, organization, and speaking style by two groups of listeners: content specialists and non-specialists. Overall, no significant changes were found, but an analysis of individual performance revealed that some speakers appeared to improve in fluency and speaking style. The main difference between the listener groups was that specialists valued content and organization more than non-specialists, and their comments tended to be more specific and mention a wider range of assessment criteria.
Study 3 explored the effects of training in pronunciation pedagogy on student teacher cognitions. Pre-service teachers from one university attended a course in phonology and pronunciation teaching, while a comparable group from another university received no specific training in pronunciation teaching. Data were collected through questionnaires and interviews. The treatment participants developed more favorable views of explicit pronunciation teaching and became more confident in their ability to teach pronunciation than the comparison group. The interviews revealed other cognition changes and several positive aspects of the course that influenced cognition development, as well as potential areas for improvement.


identifier: Levesque, J.M.  (2018) Dead Brother's Club.  Masters thesis, Concordia University.

title: Dead Brother's Club

abstract:
Dead Brother’s Club is a collection of eight short stories that look at the ways in which relationships are renegotiated after change, strain and loss. The stories portray characters with fluctuating degrees of self-awareness, forced to adapt to circumstances that have flung them from their comfort zones into the awkward, murky fissures the loss or change has opened up. “Gabor,” “Dead Brother’s Club” and “The Larper” are particularly concerned with connections between memory, commemoration and grief, while the work as a whole presents characters whose attempts at resolving their traumatic experiences are always inadequate or incomplete.

“Jane Pinches,” “The Take Out,” and “The Hemming” operate in a comic mode and rely on familiar character archetypes. They are alike in their stylization— dialogue-driven with limited expository intrusion—and in their use of hammy, absurd or tongue-in-cheek humour. While their action is often ridiculous, their emotional tenor is grounded in reality. In keeping with the other pieces in the project, what ultimately triumphs in these vignettes is the strength of the bonds between characters, which tether them to the world and cushion them from a larger alienation.


identifier: Goodarzi, Bahareh  (2018) Efficient Scheduling and High-Performance Graph Partitioning on Heterogeneous CPU-GPU Systems.  PhD thesis, Concordia University.

abstract: Heterogeneous CPU-GPU systems have emerged as a power-efficient platform for high performance parallelization of the applications. However, effectively exploiting these architectures faces a number of challenges including differences in the programming models of the CPU (MIMD) and the GPU (SIMD), GPU memory constraints, and comparatively low communication bandwidth between the CPU and GPU. As a consequence, high performance execution of applications on these platforms requires designing new adaptive parallelizing methods. In this thesis, first we explore embarrassingly parallel applications where tasks have no inter-dependencies. Although the massive processing power of GPUs provides an attractive opportunity for high-performance execution of embarrassingly parallel tasks on CPU-GPU systems, minimized execution time can only be obtained by optimally distributing the tasks between the processors. In contemporary CPU-GPU systems, the scheduler cannot decide about the appropriate rate distribution. Hence it requires high programming effort to manually divide the tasks among the processors. Herein, we design and implement a new dynamic scheduling heuristic to minimize the execution time of embarrassingly parallel applications on a heterogeneous CPU-GPU system. The scheduler is integrated into a scheduling framework that provides pre-implemented automated scheduling modules, liberating the user from the complexities of scheduling details. The experimental results show that our scheduling approach achieves better to similar performance compared to some of the scheduling algorithms proposed for CPU-GPU systems.  We then investigate task dependent applications, where the tasks have data dependencies. The computational tasks and their communication patterns are expressed by a task interaction graph. Scheduling of the task interaction graph on a cluster can be done by first partitioning the graph into a set of computationally balanced partitions in such a way that the communication cost among the partitions is minimized, and subsequently mapping the partitions onto physical processors. Aside from scheduling, graph partitioning is a common computation phase in many application domains, including social network analysis, data mining, and VLSI design. However, irregular and data-dependent graph partitioning sub-tasks pose multiple challenges for efficient GPU utilization, which favors regularity. We design and implement a multilevel graph partitioner on a heterogeneous CPU-GPU system that takes advantage of the high parallel processing power of GPUs by executing the computation-intensive parts of the partitioning sub-tasks on the GPU and assigning the parts with less parallelism to the CPU. Our partitioner aims to overcome some of the challenges arising due to the irregular nature of the algorithm, and memory constraints on GPUs. We present a lock-free scheme since fine-grained synchronization among thousands of GPU threads imposes too high a performance overhead. Experimental results demonstrate that our partitioner outperforms serial and parallel MPI-based partitioners. It performs similar to shared-memory CPU-based parallel graph partitioner. To optimize the graph partitioner performance, we describe an effective and methodological approach to enable a GPU-based multi-level graph partitioning that is tailored specifically for the SIMD architecture. Our solution avoids thread divergence and balances the load over GPU threads by dynamically assigning an appropriate number of threads to process the graph vertices and irregular sized neighbors. Our optimized design is autonomous as all the steps are carried out by the GPU with minimal CPU interference. We show that this design outperforms CPU-based parallel graph partitioner. Finally, we apply some of our partitioning techniques to another graph processing algorithm, minimum spanning tree (MST), that exhibits load imbalance characteristics. We show that extending these techniques helps in achieving a high performance implementation of MST on the GPU.


identifier: Takbash, Amirmasoud  (2018) Modeling and Design Optimization of Permanent Magnet Variable Flux Machines.  PhD thesis, Concordia University.

abstract:
Permanent magnet synchronous machines (PMSMs) with rare-earth magnets are widely used especially in traction applications as a result of their higher efficiency and torque density in comparison with other electrical motors. Due to price fluctuations and limited production of rare-earth materials, it is essential to find alternatives to the rare-earth PMSMs for different applications. This thesis focuses on the application of Aluminum-Nickel-Cobalt (AlNiCo) magnets in PMSMs. AlNiCo magnets can theoretically provide torque densities comparable to rare-earth magnets in electrical machines. The application of AlNiCo magnets in electrical machines can improve the field-weakening performance, due to the possibility of varying their magnetic flux density using armature current pulses. As a result, these machines are named variable flux machines (VFMs).
This thesis presents an analytical model for the VFM to calculate the no-load air gap flux density and consequently, the no-load back-EMF, torque peak to peak value, average torque, and magnetization current. The proposed model is used to develop an analytical design criterion for spoke type AlNiCo-based VFMs. An experimental characterization of an existing spoke type VFM at different magnetization levels is done of the torque waveform, the torque-angle characteristics, the no-load back-EMF and the magnetization/demagnetization energy. An optimization procedure to reduce the torque ripple and the magnetization current of the spoke type AlNiCo-based VFM is then proposed.
A new VFM design with radially magnetized interior magnets is presented to enhance the torque density in the field-weakening operating condition. The torque-speed and power-speed characteristics of the VFM are calculated considering the demagnetization of the AlNiCo magnets in the field-weakening region. The proposed design keeps the fully magnetized condition at both no-load and full-load conditions and provides high power densities at a wider speed range. This design is also optimized to have reduced torque ripple.
An improved core loss model is proposed and implemented in the finite element software, and an experimental method based on the flux controllability of the VFM is developed to measure the mechanical and core losses at the no-load condition. These results are then used to verify the proposed core loss model.


identifier: Asif, zunaira  (2018) Development of Life Cycle Assessment Based Air Quality Modeling and Decision Support System for the Mining Industry.  PhD thesis, Concordia University.

abstract: Air quality in mining region has been facing many challenges due to lack of understanding of atmospheric factors and physical removal mechanism. Mining operations emit various types of pollutants which could violate the environmental guidelines. The development of an integrated approach is conceptualized in this thesis as life cycle assessment based air quality modeling system (LCAQMS) for the mining industry.  LCAQMS consists of four primary models which are: (1) life cycle inventory model, (2) artificial neural network model, (3) mining-zone air dispersion model, and (4) decision analysis model. A graphical user interface (GUI) is built to integrate primary models to understand the pollutant’s fate from its generation (emission inventory) to its management (control decisions). The life cycle inventory (LCI) model is developed to determine emission inventory using inverse matrix method, and defined characterization methods are investigated to assess the environmental impact.  Artificial neural network model is developed to analyze carbon footprints (CO2 equivalent) using backpropagation method. Mining-zone air dispersion model (MADM) is developed to generate the predicted concentration of air pollutants at various receptor levels by considering the deposition effect. The meteorological factors based on atmospheric stability conditions are determined by employing the Pasquill-Turner method (PTM). The decision analysis model comprises multi-criteria decision analysis (MCDA) method and air pollution control model (APCM) to provide air pollution control alternatives and optimize the cost-effective solutions, respectively. Monte Carlo simulation accomplishes the uncertainties in the system. Moreover, an environmental risk assessment (ERA) method is extended by integrating the APCM with a fuzzy set. The applicability of LCAQMS is explored through three different case studies of open-pit metal mining in North America. Inventory results first show the air emission load for each mining activity and allow to evaluate the emission impact by linking the inventory to each impact category. Then this study helps to quantify the carbon footprints for the gold and copper mines. Also, prediction of significant pollutants such as PM10, PM2.5, SO2, and NOx at ground level has been calculated. The results depict that dry deposition is a dominate physical removal mechanism in the mining area. The LCAQMS results are evaluated with the monitoring field values, particularly MADM results are statistically tested against California puff (CALPUFF) model. Additionally, atmospheric stability is examined by analyzing the relationship between modeled PM2.5 concentrations and mixing height based on seasonal variation and the diurnal cycle. In conclusion, LCAQMS can serve as a useful tool for the stakeholders to assess the impact, predict the air quality, and aid planners to minimize the pollutants at a marginal cost by suggesting control pollution techniques.


identifier: Tousignant, Sarah Ève  (2018) Jeremy Shaw’s Quickeners and Liminals: Imagining Possible Futures.  Masters thesis, Concordia University.

abstract:
This thesis examines the artist’s cinema Quickeners (2014) and Liminals (2017), the first two episodes of The Quantification Trilogy by Berlin-based Canadian artist Jeremy Shaw (b. 1977; Vancouver, British Columbia, Canada). Quickeners, set five hundred years in the future, presents a group of immortal humans afflicted by Human Atavism Syndrome, which makes them behave like their ancestors. They perform antiquated rituals to return to a mortal state. Liminals is
set in 2117, a time when humans attribute spiritual experience to a neurological phenomenon which they are able to reproduce artificially; they thus lose the biological ability to believe. Liminals focuses on a cult-like, peripheral, altruistic group of humans who use spiritual tools and inject machine DNA into their brains to save humankind from extinction. Four themes in both artworks bring into consideration underlying fears in the present day, such as
technoanxiety, political and ecological crises, and the search for alternate forms of healing and spirituality in the American and Eurocentric world. Shaw’s works can be seen as projections of a
possible dystopic future. In his complex artist’s cinema, the protagonists use spiritual tools for transcendence, such as dance, music, and technology. The concept of atavism underlined in the
works raises questions about present-day cultural appropriation of traditional rituals. The trope of rebirth in the works recalls the myth of the god Dionysus and is presented as a way to perform time travelling in order to escape reality.