title: Registered practical nurses’ (in post RPN-BScN education) experiences of nurse-to- nurse conflict in the workplace

contributor:
Smye, Victoria
Lemonde, Manon

subject: Nurse Conflict RPN BScN School

abstract:
This research examined the experiences of nurse-to-nurse conflict of RPNs enrolled in a post RPN-Bachelor of Science in Nursing program. This study also explored how these experiences shaped their decision to return to school for a BScN to become Registered Nurses (RNs). Interpretative Phenomenological Analysis was used as the methodology to explore the experiences of six participants through in-depth individual interviews. Five themes emerged from the data analysis: the current organizational context of health care;
marginalization of the RPN; the in-between space; hierarchy, power, and privilege; and professional development and a drive for change. The findings of this research highlighted how broader contextual factors intersected and influenced conflict between nurses, and how experiencing nurse-to-nurse conflict motivated the participants to return to school for a BScN. The findings from this research have implications for nursing education, health care professionals, employers, and decisions makers when addressing and creating policies around nurse-to-nurse conflict.


title: Predicting Bitcoin: a robust model for predicting Bitcoin price directions based on network influencers

contributor:
Rahnamayan, Shahryar
Makrehchi, Masoud

subject:
Bitcoin
Predictive model
Machine learning

abstract:
The ability to predict financial markets has tremendous potential to limit exposure
to risk and provide better assurances of annualized gains. In this thesis, a
model for predicting the future daily price of Bitcoin is proposed and evaluated
in comparison to that of a purely random model. Bitcoin is a novel digital currency
that relies on cryptography instead of a central authority to verify transactions.
Without a central authority, Bitcoin requires a complete list of all transactions
to be made public so that they can be verified by all users. This unique
feature of Bitcoin, where all transactions are public, is exploited by the model
to predict the future price directions based on the actions of Bitcoin users. The
daily activity of the markets, aggregate network features, and the actions of major
network influencers are all used as features for the predictive model. Where major
network influencers are defined as users that accumulate a disproportionate
amount of wealth within the Bitcoin network compared to others. The information
about the actions of all Bitcoin users are extracted from the blockchain and
stored in a relational database for ease of use. Two metrics were created to identify
the major network influencers based on the history of their actions recorded
on the blockchain. The first metric, based on the concept of an h-index, often
used in academia to rank authors by their citations, is used to rank users by the
amount of wealth they accumulate monthly. The second metric is based on the
optimization of multiple objectives, the maximum increase in wealth with the
least amount of activity using Pareto optimization. All of the major network influencers
identified were then used as features, in combination with aggregate
network features, and market data, to test and evaluate several predictive models.
The models created were based on non-linear equations, support vector machines,
decision trees, and XGBoost; all evaluated and compared using the same
data. The XGBoost model consistently proved to be much more accurate than all
other models and was used for the final set of experiments. The XGBoost model
was compared to that of a purely random Monte Carlo model using the entire
history of data for the period of 2013–2016. The first set of experiments were conducted
using various sizes of training and testing data, in each case the XGBoost
model had an accuracy 20% greater than that of the Monte Carlo model. For
the final experiments, the model was tested in a realistic scenario, predicting the
price direction for each future day, while also being re-trained using the results
of each new day. The XGBoost model achieved a much better performance in
comparison to the Monte Carlo model, which had approximately 50% accuracy,
whereas the XGBoost model had 70%–79% accuracy.

abstract: University of Ontario Institute of Technology


title: Total knee replacement serious game for surgical education and training

subject:
Serious games
Total knee arthroplasty
Knee replacement
Virtual simulations
Interactive learning

abstract:
Traditionally, orthopaedic surgical training has primarily taken place in the
operating room. Given the growing trend of decreasing resident work hours in
North America and globally due to political mandate, training time in the
operating room has generally been decreased. This has led to less operative
exposure, teaching, and feedback for orthopaedic surgery residents. To solve
this problem, a 3D serious game that was designed for the purpose of training
orthopaedic surgery residents the steps comprising the total knee replacement
procedure. Real-time, 3D graphical and sound rendering technologies are
employed to provide sensory realism ensuring that the knowledge gained within
the serious game can be more easily recalled and applied a real world scenario.
A usability study to address user perceptions of the game’s ease of use, and the
potential for learning and engagement was conducted. Results indicate that the
serious game is easy to use, intuitive, and stimulating.


title: Showup identifications: the effects of presence of stolen property and suspect’s denial on identification performance

subject:
Showups
Eyewitness identification
System variables
Context effect
Verbal behaviour

abstract:
A showup identification is the presentation of a single suspect to an eyewitness. I used a
simulated theft paradigm and subsequent showup identification to examine the effects of stolen
property, suspects’ verbal behaviour, and target-presence on eyewitness identification
performance. I used a 2 (suspect: innocent, guilty) X 2 (stolen property: present, hidden) X 3
(verbal behaviour: denial with explanation, denial, silence) between-subjects factorial design.
Binary logistic regression analysis indicated that both the target and stolen property,
independently, and significantly predicted the accuracy of identification decisions. Surprisingly,
the presence of stolen property facilitated more accurate identification decisions from
eyewitnesses.


title: Response of Stomoxys calcitrans and Musca domestica (Diptera: Muscidae) to Volatile Organic Compound Profiles from Ontario, Canada Dairy Farms

subject:
Stomoxys Calcitrans
VOCs
Semiochemicals
Electroantennography
Chemical ecology

abstract: Stomoxys calcitrans are significant pests of dairy and beef cattle livestock facilities. Their seasonal abundance causes damage to the industry in the United States. While similar damage has been documented in Canada, the majority of the research explores population dynamics of stable flies with respect to seasonal and temporal conditions. Exploring potential semiochemical targets that impact host-parasite interactions, at livestock facilities, can give insight in creating novel integrated pest management (IPM) approaches. We have sampled Volatile Organic Compounds (VOCs) at dairy farms in Southern Ontario, to determine important components of volatile profiles at such sites. Further, we have used Gas-Chromatography-Electroantennography (GC-EAG) to identify VOCs presenting electrophysiological activity in S. calcitrans, for further exploration of their significance in behavioural modification. The data collected illustrates that VOC profiles taken at livestock facilities are subject to change over the summer months, and has produced novel targets for IPM programs.


title: A framework for proactive fault tolerance in cloud-IoT applications

subject:
Fault tolerance
Failure analysis
Failure prediction
Internet of Things
Cloud computing

abstract:
Integrating Internet of Things (IoT) devices with the cloud has several benefits, including expanding local IoT resources and improving cloud-IoT application performance. Cloud computing can benefit from IoT devices and applications by extending its scope to include real-world surroundings. On the other hand, IoT can use the cloud’s unlimited computing and storage power. Modern cloud-based applications, including smart cities, home automation, and eHealth, require a highly scalable and available framework that enables computing, storage, and data analysis. Cloud computing cannot respond to the growing number of IoT devices due to its remote location, and cloud providers are struggling to meet the quality of service (QoS), such as low latency. Cloud applications have a high probability of failure as they operate in a large-scale environment, including physical and virtual machines. The Coronavirus pandemic (COVID-19) has tested cloud providers in many ways, none of which could have been predicted. Although the public cloud has proven remarkably resilient in overcoming an unprecedented stress test, there are remarkable exceptions to cloud failure problems that occurred in the first half of 2020.
In this thesis, the main objective is to design and implement a cloud-IoT framework that has been developed utilizing proactive fault tolerance techniques to provide high reliability and availability for IoT applications. The framework aims to decrease the number of task failures and minimize the time and cost of using the cloud. This thesis also analyzes and characterize the behaviour of failed and finished tasks using publicly accessible traces.
A design of highly reliable and available IoT applications has been proposed based on the development of Edge-Cloud architecture to support modern IoT applications. The evaluation results show a significant correlation between unsuccessful tasks and the resources requested. The results indicate that the proposed framework performance has improved, as well as the throughput efficiency increases by 55% after integrating the local resources with the cloud. The machine and deep learning-based failure prediction model can reduce the number of failed tasks for cloud-IoT applications. Moreover, the failure prediction model can predict failed tasks with a high rate of precision, recall, and F1-score.


title: OLSR-based network discovery in situational awareness system for tactical MANETs

subject:
TMANET
Situational awareness
Topology discovery

abstract:
In this thesis, we propose a high level design for connectivity visualization of OLSRbased
MANET topology based on local topology databases available in an OLSR node.
Two different scenarios are considered: a central (full view) topology from a command
and control location, or a nodal (partial) view from an ad-hoc node. A simulation-based
analysis is conducted to calculate total number of active links at a particular time in full
and nodal topology views. Also the error rate of network topology discovery based on
total undiscovered link both mobile and static scenario is considered and reported. We
also come up with an analytical model to analyse the network bandwidth and overhead of
using TC, HELLO and custom NIM message to evaluate the performance of centralized
visualization to build full map of the network with respect to situational awareness
system. This thesis also presents a multi-node, 2-dimensional, distributed technique for
coarse (approximate) localization of the nodes in a tactical mobile ad hoc network. The
objective of this work is to provide coarse localization information based on layer-3
connectivity information and a few anchor nodes or landmarks, and without using
traditional methods such as signal strength, Time of Arrival (ToA) or distance
information. We propose a localization algorithm based on a Force-directed method that
will allow us to estimate the approximate location of each node based on network
topology information from a local OLSR database. We assume the majority of nodes are
not equipped with GPS and thus do not have their exact location information. In our
proposed approach we make use of the possible existence of known landmarks as
reference points to enhance the accuracy of localization.


title: Nonlinear vibration and frequency response analysis of piezoelectric-based nanotube resonators

subject:
Nanotube
Nonlinear vibration
Frequency response

abstract: To study the vibration behaviour of nanotube-based structures, different models of nanotubes under the effects of piezoelectric layer, intermediate mass, fluid flow and structure curvature are developed. The frequency responses of proposed models for both free and forced vibrations under single frequency, multi-frequency and parametric excitations are investigated. The Hamiltonian principle and Lagrangian method are associated with non-local non-classical theory to develop the nonlinear vibration models and two strong methods known as Galerkin technique and multiple scales method are employed to find the solutions of the developed systems equations.


title: Development of an obstacle detection and navigation system for autonomous powered wheelchairs

subject:
Robotics
Autonomous wheelchair
Obstacle detection
Slope and stair detection
Autonomous navigation

abstract: This thesis describes the development and prototyping of an after market system to convert an electric powered wheelchair into an autonomous wheelchair. The purpose of this research is to automatize powered wheelchairs for children who are impacted by conditions such as cerebral palsy. Maneuvering a powered wheelchair with a joystick is difficult and painful for users who have a high level of cerebral deficiency and other chronic conditions. The autonomous powered wheelchair is designed to maneuver in an indoor environment whilst avoiding static and dynamic obstacles. The add-on system comprised of stereo vision sensors (ZED Camera), and IMU is designed to use Robot Operating System (ROS) to communicate and control the movement of the wheelchair. With the addition of a 3D map of the environment generated using visual sensors through ROS packages, the system identifies and avoids obstacles. Simultaneous Localization and Mapping (SLAM) and autonomous navigation packages were tested and modified. Slopes and drops identified in the 3D map are converted such that they are compatible with the 2D navigation packages of ROS. Configuration settings were determined and tested to ensure that the system works as required. The results demonstrated that the powered wheelchair can be modified to become an autonomous wheelchair using ZED Camera and IMU, such that it can navigate indoors effectively avoiding static and dynamic obstacles.


title: Analysis of the volatile organic compounds produced by the decomposition of pig carcasses and human remains

contributor:
Forbes, Shari
Desaulniers, Jean-Paul

subject: Forensic chemistry

subject: Remains detection

subject: VOCs

subject: Cadaver dog

subject: Thermal desorption

subject: Comprehensive two-dimensional gas chromatography

subject: Time-of-flight mass spectrometry

abstract:
Complex processes of decomposition produce a variety of chemicals as soft tissues and their component parts are degraded. Among others, these decomposition by-products include volatile organic compounds (VOCs) responsible for the odour of decomposition. Human remains detection (HRD) canines utilize this odour signature to locate human remains during police investigations and recovery missions in the event of a mass disaster. Currently, it is unknown which compounds or combinations of compounds are recognized by the HRD canines. In this study decomposition VOCs were collected from the decomposition headspace of pig carcasses and were analyzed using thermal desorption gas chromatography mass spectrometry (TD-GC-MS). The difficulties associated with the non-target analysis of complex samples led to the further analysis of decomposition odour using a novel application of thermal desorption coupled to comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (TD-GCxGC-TOFMS). The additional peak capacity and spectral deconvolution of the GCxGC-TOFMS system generated a characteristic profile of decomposition VOCs across the various stages of soft tissue decomposition. The profile was comprised of numerous chemical families, particularly alcohols, carboxylic acids, aromatics and sulfides. Characteristic compounds identified in this study included 1-butanol, 1-octen-3-ol, 2-and 3-methyl butanoic acid, hexanoic acid, octanal, indole, phenol, benzaldehyde, dimethyl disulfide and trisulfide, which represent potential target compounds of decomposition odour.
Currently there is a demand for improved canine training aids and pig carcasses have been proposed as an alternative due to their acceptance as human body analogues. This work investigated the similarities in the decomposition odour profile of pig carcasses and human remains through surface decomposition trials and comparisons to the published literature. It was determined that pig carcasses cannot be eliminated as potential human decomposition odour mimics. Additionally, following the examination of commercially available synthetic training aids, pig carcasses demonstrated a more suitable profile for the training of cadaver dogs. Further investigation into the chemical composition of decomposition odour utilizing TD-GCxGC-TOFMS will aid in determining the signature of human decomposition odour and facilitate the comparisons of these profiles between environments, individuals and species.


title: Optimized clean hydrogen production using nuclear small modular reactor and concentrated solar power as a renewable energy source

contributor:
Tokuhiro, Akira
Genco, Filippo

subject:
Hydrogen production
Small modular reactors
Renewable energy
Thermochemical cycles
Multi-objective optimization

abstract: According to current predictions, hydrogen will serve as a key fuel and energy source by decreasing greenhouse gas (GHG) emissions. In this research an integral Pressurized Water Reactor-type Small Modular Reactor (iPWR-type SMR), connected to a molten-salt based Concentrated Solar Power (CSP) plant, producing electricity and hydrogen is investigated specifically, by modeling and simulations of a Nuclear-Renewable Hybrid Energy System (N-RHES). Optimization of design and functional variables/parameters, as complexity in system engineering, are considered as scenarios. The major results of this research is that multi-objective optimization provides recommended, operational scenarios to obtain preferred results in spite of variability of sunshine in terms of objectives, which are maximizing total profit and total heat equivalent. This research carried out based on modeling and simulations on MATLAB and Genetic Algorithms (GAs) for optimization is key for real life applications. Moreover, in terms of SMR safety-in-design, important time slots are given and explained in this thesis.

abstract: University of Ontario Institute Technology


title: Detection of gasoline from internal tissues for use in determining victim status at the time of a fire

contributor:
Forbes, Shari
Easton, Brad

subject:
Forensic science
Fire investigations
Fire chemistry
Ignitable liquid residues,
Accelerants
Gas chromatography-mass spectrometry

abstract:
In Ontario, fire investigators from the Office of the Fire Marshal (OFM) are responsible for determining the origin and cause of suspicious fires. As part of the investigation, fire debris samples are collected from the scene and analyzed by the Centre of Forensic Sciences. The standard practice is to collect items that are porous, highly absorbent or adsorbent with high surface areas as they allow for better retention of the ignitable liquids. The evidence typically collected includes carpets, cardboards, soils, cloths and other items that have not been impinged by flame such as beneath baseboards. These samples are analyzed for the presence of ignitable liquid residues which may be evidence that an accelerant was used at the fire. When a body is recovered from a fire it can provide another source from which to collect samples for analysis. These samples can be especially helpful in instances where the fire generated an intense heat which may cause a loss of ignitable liquid residues from the fire debris. The tissue samples have a greater likelihood of still containing residues as the organs and body fluids can act as a shield protecting the residues from volatilization.
The purpose of this study is to validate whether a victim was alive or deceased at the time a fire was intentionally set by detecting presence or absence of gasoline residues within their lungs and heart blood post fire. It was hypothesized that only when a victim was alive and performing respiration would sufficient gasoline vapours enter the airways and bloodstream for detection postmortem. Contamination becomes a significant issue when these samples are collected at autopsy and this study aimed to determine the accuracy with which a gasoline signature can be interpreted following the collection and analysis of lung tissue and heart blood.
Pig (Sus domesticus) carcasses were chosen as acceptable analogues for humans in this study. The experiments involved anaesthetizing a pig (with Animal Ethics Approval), exposing the pig to gasoline vapours for 10 minutes, and then euthanizing it. The carcass was clothed with a cotton t-shirt and placed in a house where additional gasoline was poured onto it. The house also contained two additional clothed pig carcasses which did not inhale gasoline vapours; one with gasoline poured directly onto it and the other with no gasoline exposure (negative control). Thermocouples were placed under each carcass and in the centre of each room at ceiling and floor level to record the temperature. The house was set ablaze and monitored by a volunteer fire service. After the fire had reached
V
flashover and was suppressed, the carcasses were collected and their lungs and heart blood excised at a necropsy. The lungs and heart blood were then placed into glass mason jars following the OFM protocol. The headspace from each sample was analyzed by thermal desorption-gas chromatography-mass spectroscopy to determine the presence or absence of a gasoline signature. Two full scale house fires were conducted in order to obtain three replicates.
The results showed that only the lungs and heart blood from the pig that inhaled gasoline contained gasoline residues. This indicates that it is possible to determine a victim’s status at the time of the fire based on the detection of gasoline in the lungs and/or heart blood. It was also concluded that contamination of samples during an autopsy can be minimized by changing gloves before handling the internal tissues. The thermal data showed that the bodies act as an insulator and protects the underside as the temperatures under the carcasses did not exceed 30⁰C while the room reached over 900⁰C at the first full scale house fire.
These results will impact the forensic community by demonstrating the importance of analyzing a deceased victim’s internal tissues for ignitable liquid residues post fire as they may provide evidence of an intentionally set fire as well as providing information about the victim’s status when a fire was started. These findings will have a direct impact to the OFM as additional evidence can be obtained by completing internal tissue analysis. This will intern impact the Centre of Forensic Science (CFS) as it confirms the importance of analyzing internal tissues in order to provide results to fire investigators. Finally these findings should be used to implement new protocols at the Coroner’s Office so contamination can be minimized during fire autopsies and accurate samples are collected and sent to the CFS for analysis.


title: SDTDMn0 : a multidimensional distributed data mining framework supporting time series data analysis for critical care research

contributor:
McGregor, Carolyn
James, Andrew
Calley, Christina

subject:
Distributed data mining
Temporal abstraction
Relative alignment
Time series data analysis
NICU

abstract:
Premature birth is one of the major perinatal health issues across the world. In 2007, the
estimated Canadian preterm birth rate was 8.1 % (CIHI, 2009). Recent research has shown that
conditions, such as nosocomial infections or apnoeas, exhibit certain variations in the baby's
physiological parameters which can indicate the onset of the event before it can be detected by
physicians and nurses. Neonatal Intensive Care Units are some of the highest information
producing areas in hospitals. The multidimensional and distributed nature of the data further adds
another layer of complexity as physiological changes can occur in one data stream or can be
cross-correlated between several streams. With the collection and storage of electronic data
becoming a global trend, there is an opportunity to analyse the collected data in order to extract
meaningful information and improve healthcare. The aforementioned properties of the data
motivate the need for a framework that supports analysis and trend detection in a
multidimensional and distributed environment.


title: Design automation and QoS requirements preservation for multiprocessor embedded systems

subject:
Embedded systems
Task scheduling
Design automation
Parallel computing
Calibration

abstract:
The number of processors is increasing in embedded systems but the usefulness of parallel computation is not better leveraged due to the inflexibility of design and implementation for multiprocessor embedded system applications. A higher level abstraction (i.e., a parallel programming framework) can ease the programmers to define parallelism for tasks in an application, but designers still face the complexity of mapping high-level requirements to the syntax and semantics of a parallel programming interface. Nevertheless, embedded system applications execute various periodic tasks that are carried out repeatedly within a certain time interval. Each task is characterized by its deadline where it is expected to perform a function producing a correct result within a specified amount of time. These tasks may be able to run in parallel to utilize the system efficiently. Moreover, embedded systems often interact with dynamic environments requiring not only to meet deadlines of tasks but also to achieve a certain level of accuracy as the inaccuracy of a task output produces a similar adverse effect like timing violation. Therefore, it requires an automated design process to map the tasks to lower level and a monitoring framework to meet the high-level requirements of embedded system applications.
This thesis presents a parallel loop-based task construct to automate the design process of embedded applications from Architecture Analysis and Design Language (AADL) models and demonstrates how to preserve the requirements at lower-levels. AADL is practiced to model the software and hardware architecture of embedded systems. Since most of today's embedded systems either belong to soft real-time systems (i.e., stream processing systems) or weakly-hard real-time systems (e.g., control systems), we adopt a new task scheduling approach in a well-known parallel programming interface called OpenMP for increasing determinism in soft real-time system (RTS) applications. Moreover, we propose a calibration framework to increase the robustness of weakly-hard real-time system applications that rely on time-driven scheduling approaches such as rate monotonic (RM) scheduling. In this thesis, determinism and robustness are the way of measuring the quality of service (QoS) requirements of tasks. For increasing the robustness of weakly-hard real-time systems, the calibration framework is used by which the system component's output accuracy can be monitored and compared with a calibration standard. The calibration standard is derived from a representative component's output with known high accuracy. As an example, we analyze the accuracy of a component that performs dynamic voltage and frequency scaling (DVFS) and explains the associated timing effects in terms of task schedulability.
To illustrate the applicability of our mechanism, the experimental analysis incorporates a design automation process for mapping tasks to parallel programming framework in soft RTSs, a calibration framework for monitoring task output in weakly-hard RTSs. To understand the calibration framework, a software-based monitoring approach is shown for a resistive voltage divider as a case study. Therefore, we use a cost estimation model to demonstrate the efficiency of the automation process and map tasks over multiple processor cores using OpenMP. To ensure meeting high-level requirements of embedded system applications, we analyze the existing OpenMP scheduling mechanisms and propose a layer of adaptation. We show that our proposed adaptation layer facilitates a tighter execution time bound for time-sensitive tasks or a better throughput for tasks that require higher QoS. Thus, the proposed design automation framework is applicable for a variety of applications with different QoS requirements preserved at the lower level. To monitor the QoS of task output, we perform experiments on LITMUSRT kernel to demonstrate the need and applicability of our calibration framework in the domain of embedded systems. The experimental results illustrate that the proposed approach yields more predictability and show better performance for preserving QoS requirements of tasks.


title: Development and application of an integrated aerodynamic and thermodynamic testing system for cars

subject: Aerodynamic Thermodynamic Aero-thermal Cars Improvement

abstract: In this thesis an integrated aerodynamic and thermodynamic testing system was developed. It consists of an incremental force measuring system (FMS) that was designed and constructed. In addition, a testing protocol was developed to integrate aerodynamic and thermodynamic testing in the climatic wind tunnel at UOIT. The FMS was calibrated and used to improve the aerodynamics of four race cars. Furthermore, a thermodynamic test consisting of temperature measurements, and a flow visualization study using tufts were conducted. The aerodynamic study showed that a set of aerodynamic devices can significantly alter the drag force and downforce on cars. However, a little angularity of a device, such as the side front canards, to the flow direction, can significantly alter its function. The flow visualization test showed that the local flow direction strongly depends on the local geometry. The temperature study revealed that the underbody cooling was jeopardized by a rear underbody diffuser.


title: An exploration of SDT need fulfillment in a synchronous online learning environment

contributor:
Ruttenberg-Rozen, Robyn
Kay, Robin

subject:
SDT
Online learning
Synchronous
Motivation

abstract:
In this paper, I report results from a qualitative case study that explores SDT need fulfillment within a synchronous online learning environment. SDT addresses how the sociocultural conditions an individual experiences impact their motivation, development, and wellness. An individual who experiences sociocultural conditions that satisfy their needs for autonomy, competence, and relatedness will develop autonomous motivation. As course instruction moves online, it is important to understand if and how online learning spaces can impact learner motivation. My data analysis and resultant code network reveal the fulfillment of the SDT need fulfillment pathway within a synchronous online learning environment.
Additionally, the code network reveals that the structure of a course, the quality of communication and feedback, the provision of choice, and the instructor’s personability and commitment are all linked to need fulfillment. This study’s implications will inform course design within online learning environments and future research in online learning.


title: Metabifurcation analysis of a phenomenological ventricular cell model

subject:
Alternans
Bifurcation analysis
The Fenton-Karma model
PCA

abstract:
Heart disease is the leading cause of death in America, and arrhythmia is considered one of the most important precursors of heart attacks. We cannot predict arrhythmia directly; however, it has been shown that cardiac alternans is closely related to arrhythmia[35]. Therefore, predicting alternans could be the _rst step in preventing arrhythmia. Fenton and Karma(1998)[10] came up with the Fenton-Karma model (the F-K model) with three variables and 13 parameters that is a relatively simple and basic model that including information on alternans. Our research is based on the F-K model at the cell level rather than the tissue level.
We study the parameter space of the F-K model and discover robust correlations between parameters and dynamical responses. The relations cannot be disclosed by some statistical methods like principal component analysis(PCA) or K-means clustering because we cannot see the dynamical behaviors of parameter sets.
The links instead emerge when the parameter space is partitioned according to bifur-
cation responses. We call this general method \metabifurcation analysis". Concretely,
the bifurcation responses are shown by the bifurcation plots, which show the model re-
sponses, like action potential duration(APD) restitution curves, to a sequential change in pacing frequency. According to the bifurcation patterns, we partition the parameter space in _ve \parent families". After investigating and characterizing them in depth, we subtly classify the largest parent families into four subfamilies. We discuss their essential differences in qualitative dynamical behaviors like whether they exhibit bistability and how solutions change after alternans appears.
The partitioning cannot be achieved by the investigation of only a small number
of parameter sets. To obtain a relatively large number of parameter sets to make the
results reliable, we implement a particle swarm optimization process with parallel pro-
gramming interfaces like OpenMP and Open MPI to search the parameter space and
obtain 1,525,833 physiologically admissible parameter sets; then, we randomly choose a representative sample of 270,000 parameter sets to do the bifurcation analysis.
After doing the metabifurcation analysis on the the F-K model, some results are listed
as follows. First, more than 70% parameter sets from 270,000 meaningful parameter sets do not or only have one period-doubling bifurcation. Second,t-w plays the leading role of identifying subfamilies in the parent family(PF2) with only one period-doubling bifurcation; Moreover, in one subfamily(F3), there is a positive linear relation between t-w and the appearance of bistability.


title: Specifics of forced-convection heat transfer in a vertical 7-element bundle cooled with upward flow of SuperCritical Water

subject: Heat Transfer Nusselt number Correlation

subject: SuperCritical Water Reactor (SCWR)

subject: Nuclear Engineering

subject: Fuel Bundle

subject: Small Modular Reactor (SMR)

abstract:
Current Generation II/III/III+ Nuclear Power Plants (NPPs) are no longer economically competitive partially due to low thermal efficiencies.
Six Generation IV NPP concepts were proposed having increased thermal efficiency, with Canada investigating the SuperCritical Water Reactor (SCWR) concept. However, determining Heat Transfer specifics for SuperCritical Water in bundle configurations is required.
Many empirical Nusselt number (Nu) correlations derived from bare tubes are available, with only one derived from a bundle. No assessments of Nu correlations are available for 7-rod bundle datasets, representing the centre of 37-element bundles currently used in Canadian NPPs.
A Nu correlation derived from a 7-rod bundle dataset is proposed, and assessed against 35 common Nu correlations, using Root Mean Square error and graphical investigation. The assessment indicates the proposed Nu correlation is the most suitable for 7-rod bundles and bare tubes.
One typical Canadian SCWR design is confirmed based on maximum fuel centreline and sheath temperatures.

abstract: University of Ontario Institute of Technology


title: Analysis and evaluation of transactive energy control in active distribution systems

subject:
Energy storage
Electric vehicles
Solar photovoltaics
Transactive energy
Transformer loss of life

abstract: The electric power distribution system is experiencing significant operational changes due to the integration of plug-in electric vehicles and intermittent distributed energy resources such as rooftop solar photovoltaics. As plug-in electric vehicle charging represents a significant increase in system loading, both distribution transformers and substation transformers are subject to overload conditions which rapidly degrade transformers lifetime. Furthermore, the increased penetration of rooftop solar photovoltaic in the residential sector may lead to bi-directional power flow and may additionally cause overload to the distribution transformers. In order to accommodate the growing market penetration of plug-in electric vehicles and rooftop solar photovoltaics, the electric utility must employ energy management to prolong the transformers lifetime. Given that transformers represent one of the most expensive assets in the distribution system, failure to resolve transformer lifetime degradation issues require the electric utility to incur the costs of transformer replacement or upgrading. The work in this dissertation proposes a transactive energy control methodology to perform residential energy storage system control as a means of reducing transformer lifetime degradation. The results have shown that the proposed framework may extend median annual distribution transformer lifetime by nearly double the expected lifetime of distribution transformers without transactive energy control. Finally, the proposed transactive control scheme has also been found to reduce active power losses within the system.


title: Development and characterization of a dual neutron and gamma detector

subject:
Monte Carlo radiation transport
Lithium iodide (Europium) scintillator
Neutron and gamma mixed field
Inorganic crystal

abstract: A dual neutron and gamma detection system has been developed for online measurements. The system consists of a single crystal mounted on a photomultiplier tube to detect simultaneously gamma radiation as well as thermal neutrons. A compact data acquisition system has been used for neutron and gamma discrimination. The system has been tested with different gamma energies and with an Am-Be neutron source at the University of Ontario Institute of Technology neutron facility. This thesis presents the characteristics of the developed detector, and experimental data carried out in different experiments in different fields.


title: Numerical methods for simulating diffusion in cellular media

subject:
Immersed boundary method
MRI
Diffision
Inhomogeneous

abstract:
Diffusion imaging is a relatively recent branch of magnetic resonance imaging that
produces images of human physiology through diffusion of water molecules within the
body. One difficulty in calculating diffusion coefficients, particularly in the brain, is
the multitude of natural barriers to water diffusion, such as cell membranes, myelin
sheaths, and fiber tracts. These barriers mean that water diffusion is not a homogeneous
random process. Due to the complexity of modeling these structures, a simplifying
assumption made in some methods of data analysis is that there are no barriers
to water diffusion. We develop tools to simulate the diffusion of water in an inhomogeneous
medium, which may then be used to test the accuracy of this assumption. The
inherent difficulty (and computational cost) of including barriers (e.g., cell membranes)
can be lessened by employing the immersed boundary (IB) method to represent these
structures without the need for complicated computational grids. The contribution of
this thesis is the implementation and validation of an IB method that allows for diffusion
across semi-permeable membranes. The method is tested for a square interface
aligned with the computational grid by comparing it to a second numerical scheme
that uses standard finite differences. We also calculate the rate of convergence for the
IB method to assess the numerical accuracy. To demonstrate the flexibility of the IB
method to simulate diffusion with any interface shape, we also present simulations for
irregular interfaces.


title: Youth correctional officer orientation and opinions on relationships with youth

subject:
Youth
Custody
Correctional officer
Correctional orientation
Relationship

abstract: This study explored the personal perspectives of current and past youth correctional officers within secure and open custody facilities in Ontario. A multi-methods design was used to examine officers’ orientation to their work, how they view their interactions with youth and their opinions on relationships with youth in custody. Quantitative data was collected to assess demographics, correctional orientation, and officer typology. Qualitative open-ended survey responses probed exploratory areas of interest such as participants’ descriptions of their day, their thoughts on relationships with youth, and their general approach to their work. Although there was a small sample size (N=26), the results indicated that there may be some important relationships between correctional orientation and beliefs around relationships in youth correctional officers. As suggested in previous literature, youth correctional workers report their job as including various tasks ranging from supervision and security to cleaning and preparing meals. There are also indications of differences in correctional orientation and endorsements for relationship development with youth for those who see treatment as part of their role in rehabilitation and those who do not. Additionally, there does not appear to be the groupings of officer types in this youth correctional worker sample as is seen in adult correctional workers. This exploratory study provides a starting point for understanding the unique experiences and duties of youth correctional workers, their correctional orientation, and their views on relationship development with youth. Future research will focus on replicating these findings with a larger sample size.


title: Influence of forced convection on sessile droplet evaporation

subject:
Sessile droplet
Evaporation
Forced convection

abstract: Evaporation is a phase change process with potential for achieving large heat transfer rates under high air temperatures due to the latent heat of vaporization. Bioin-spired artificial perspiration systems can leverage the evaporation of sessile droplets to implement this effect for different cooling applications. In the case of human perspiration, droplet evaporation typically occurs under exposure to moving air, or forced convection. However, current approaches to understanding droplet evaporation primarily use a vapour-diffusion limited model. Experiments using an open-loop wind tunnel and computer-vision based control system were conducted to measure evaporation rates of continuously-fed sessile droplets under forced convection. Results demonstrated increases to the evaporation rate with the inclusion of forced convection and removal of the vapour-diffusion limit, but also shows evidence for a limit based on thermal behavior. Additional experiments also demonstrate boundary layer effects caused by adjacent droplets suppresses increases to the evaporation rates from forced convection.


title: Study on linking a SuperCritical water-cooled nuclear reactor to a hydrogen production facility

contributor:
Gabriel, Kamiel
Pioro, Igor

subject: Hydrogen production

subject: Thermochemical cycles

subject: Copper-chlorine cycle

subject: Generation IV reactor

subject: Heat exchanger

abstract: The SuperCritical Water-cooled nuclear Reactor (SCWR) is one of six Generation-IV nuclear-reactor concepts currently being designed. It will operate at pressures of 25 MPa and temperatures up to 625°C. These operating conditions make a SuperCritical Water (SCW) Nuclear Power Plant (NPP) suitable to support thermochemical-based hydrogen production via co-generation. The Copper-Chlorine (Cu‒Cl) cycle is a prospective thermochemical cycle with a maximum temperature requirement of ~530°C and could be linked to an SCW NPP through a piping network. An intermediate Heat eXchanger (HX) is considered as a medium for heat transfer with operating fluids selected to be SCW and SuperHeated Steam (SHS). Thermalhydraulic calculations based on an iterative energy balance procedure are performed for counter-flow double-pipe design concept HXs integrated at several locations on an SCW NPP coolant loop. Using various test cases, design and operating parameters are recommended for detailed future research. In addition, predicted effects of heat transfer enhancement on HX parameters are evaluated considering theoretical improvements from helically-corrugated HX piping. The effects of operating fluid pressure drop are briefly discussed for applicability in future studies.


title: Model based simulation of broaching operation: cutting mechanics, surface integrity, and process optimization

subject:
Broaching operation
Tool design
Surface integrity
Optimization
Solid modelling

abstract:
Machining operations are widely used to produce parts with different shapes
and complicated profiles. As a machining operation, broaching is commonly used
for the machining of a broad range of complex internal and external profiles either
circular or non-circular such as holes, keyways, guide ways, and slots on turbine
discs having fir-tree shape. Broaching is performed by pushing or pulling a tapered
tool through the workpiece to remove the unwanted material and produce the
required profile. Broaching is also acknowledged because of its high productivity
and attainable surface quality in comparison to the other machining processes.
The objective of this thesis is to simulate the broaching operation and use the
results to present a methodology for optimum design of the broaching tools. In the
course of the presented thesis, a new B-spline based geometric model is developed
for broaching cutting edges followed by model validation using 3D ACIS modeller.
To study the mechanics of cutting and generated cutting forces during
broaching operation, an energy based force model is presented which can predict
the cutting forces based on the power spent in the cutting system. An experimental
investigation is conducted in order to confirm the estimated forces.
The integrity of the broached surface is also investigated by focusing on
surface roughness, subsurface microhardness, and subsurface microstructure as
three major parameters of surface integrity.
An optimization procedure for broaching tools design is presented in this
thesis. A mathematical representation of broaching tooth geometry is also
presented which is used to simulate the tooth as a cantilevered beam subjected to
a distributed load. The beam is solved considering the given design constraints to
achieve optimum geometric parameters for maximum durability and performance.


title: Design and control of FACTS-based high performance microgrid

subject:
Microgrid
FACTS
Fuzzy
Genetic algorithm
DER

abstract: The current power grid introduces many limitations and challenges in a world that is heavily dependent on electricity. Many government agencies, utility companies, researchers and engineers in the electric power industry have envisioned of transforming the existing grid into MicroGrid. To facilitate domestic consumers’ ratings and needs, a microgrid has been developed that includes Distributed Energy Resources (DER). It is expected to be an intelligent, sustainable, resilient and reliable power grid suitable for the 21st century economy. Some of the main concerns for any grid are power quality and efficiency as well as reactive and active power reliability for consumers. To manage active and reactive power Flexible AC Transmission System (FACTS) technology is used to improve power quality and efficiency. Since FACTS technologies have been developed, much research has been done to acquire more accurate and reliable techniques and algorithms to implement FACTS in the power system. The current microgrid scheme implemented with FACTS, produces a highly efficient response monitored with different KPI indicators of the microgrid. A newly developed AC/DC microgrid design with FACTS technology includes DER, which consist of DC batteries, wind Turbines, PV systems (Solar photovoltaic system) and diesel generators. Modulated Power Filter Compensators (MPFC) for AC and Green Plug Filter Compensators (GPFC) for DC are used as FACTS controller. Optimization based on genetic algorithms and intelligent control through fuzzy logic, are defined to optimize the performance of the microgrid. Optimization and intelligent control are accomplished by self-adapting the controller gains and converters gains to achieve the best microgrid energy utilization, stabilization of voltage and reduction inrush current conditions. Key performance indicators are as follows: bus voltages stabilizing, feeder losses reduction, power factor enhancement, improvement of power quality and reduction of the total harmonic distortion at AC interface buses that are compared with and without FACTS criterion. The AC/DC microgrid is modeled in both grid and islanded connected modes.


title: Analysis of peptide production by Lactobacillus species and evaluation of their antihypertensive and immunomodulatory activities

subject: Lactobacillus Dairy Peptide Immunomodulatory Antihypertensive

abstract: Cardiovascular disease (CVD) is the leading cause of death among Canadian adults. Research has demonstrated an inverse relationship between the consumption of fermented dairy products and a decreased risk of CVD due to lactic acid bacteria used in the fermentation process which liberate small bioactive peptides from larger milk proteins (eg. casein). We observed that supplementation with 0.1% casein significantly increased the growth rate of L. helveticus R0389 and L. rhamnosus R0011 and increased the ACE-inhibitory activity of their secreted peptide fractions. Peptide-containing supernatants of L. rhamnosus R0011 show comparable ACE inhibition to known antihypertensive peptides, VPP and IPP. Supernatants of milk ferments induced the production of the regulatory cytokine, IL-10, by THP-1 monocytes. Novel antihypertensive and immunomodulatory activities of individually synthesized peptides were also reported. By investigating the relationship between these bioactive properties, we can improve upon the use of probiotic organisms to confer maximal health benefits to Canadians.


title: Investigating the effectiveness of infant feeding school-based education on the breastfeeding knowledge and attitudes of adolescent female students

subject: Breastfeeding Education School-based Attitudes Knowledge

abstract:
Objective: To design and pilot test a school-based educational breastfeeding intervention on the
breastfeeding knowledge, attitudes and future infant feeding intentions of secondary school
adolescent females.
Design: A one-group, pre-test/post-test, quasi-experimental design
Methods: A convenience sample of 77 adolescent secondary school female students received
one 70-minute educational breastfeeding session during health education classes in a secondary
school in Ontario. Data was collected using self-administered questionnaires at baseline and one
day post-intervention. A modified version of the Iowa Infant Feeding Attitude Scale (IIFAS) and
a modified Breastfeeding Knowledge Scale were used to measure breastfeeding attitudes and
knowledge of participants. Additional outcomes measures included future breastfeeding
intentions and students’ perceptions of the educational session.
Results: Breastfeeding knowledge (p<0.001), attitude (p<0.001) and future intentions of
participants to exclusively breastfeed increased significantly (p<0.05) at post-test. The
participant feedback indicated that they found the content useful, interesting and the information
was presented in an engaging manner.
Conclusion: These findings suggest that adolescent female students may be receptive to learning
about breastfeeding in school and a single school-based educational breastfeeding intervention
can positively impact their breastfeeding knowledge, attitude and future intentions. The
secondary school setting may be an appropriate setting for the inclusion of educational
breastfeeding content to increase awareness of the benefits, importance and physiology of human
lactation and enable future informed decision making.


title: Effects of dietary fermentable material on innate and adaptive immune measures in male and female rats under resting and immunized conditions

subject: Cytokines Immunoglobulins Microbiota Sex Fibre

abstract: Sex-based differences in immune parameters are well recognized, and recent evidence suggests differences in microbiota composition between sexes, necessitating assessment of effects of dietary fermentable material (DFM) in both males and females. Effects of consumption of DFM of differing composition (Wheat Bran (WB), Oat Bran (OB), Resistant Starch (RS), Fructooligosaccharides (FOS)) on the immune system were compared under resting and immunized conditions between sexes. The gut microbiota composition and short chain fatty acid profiles differed between rats fed different DFM and also differed between sexes following FOS consumption. Immune parameters were analyzed for the effect of diet, differences between sexes or interactions (diet x sex), to detect the effect of DFM on male and female rats. The kinetics of primary (Day 0, 5, 10, 15) and secondary antibody responses (Day 21) were measured following immunization with a T cell-dependent antigen, Keyhole Limpet Hemocyanin (KLH). Under resting conditions, male rats had more FoxP3+ Treg cells in the mesenteric lymph node (MLN) and spleen than did females. Levels of the regulatory cytokine TGF-β1 also increased in the MLN in a DFM-dependent manner. In contrast, percentages of MLN and splenic CD68+ macrophages and levels of gut tissue IL-10 were higher in females than males. These results suggest immune regulation at the mucosal level is controlled in a differential manner between sexes and was affected by DFM intake only in males. At the systemic level, DFM intake delayed the primary anti-KLH IgG antibody response kinetics in male (control>>WB>OB>RS>FOS) and female (control> FOS>WB>RS>OB) rats. The secondary anti-KLH IgG response in control-fed males was 10-fold higher than in control-fed females. DFM intake in males significantly decreased anti-KLH IgG levels relative to control-fed males. Collectively, these findings demonstrate DFM consumption in males potentially induces systemic immune regulation leading to a delayed response to immune challenge, an effect that was not observed in females.


title: Implicit gaze interaction for information visualization

subject:
Gaze estimation
Feature detection
Attention modelling
Implicit interaction
Overplotting visualization

abstract: This thesis presents a novel marker-free method for identifying screens of interest when using head-mounted eye-tracking for visualization in cluttered and multi-screen environments. The presented approach offers a solution for discerning visualization entities from sparse backgrounds by incorporating edge-detection into the existing pipeline. The system allows for both more efficient screen identification and improved accuracy over the state-of-the-art ORB algorithm. To make use of this pipeline in visualization applications, a model is introduced to track a user’s interest in rendered visualization objects by collecting the gaze data and calculating the object group’s interest scores across selected visual features. With the interest model, We offer an implicit gaze interaction system that provides subtle interaction supports to improve group-of-interest objects visibility and to ease object selection in crowded regions of information visualizations.


title: The toxicity of Harmony Landfill Leachate to Green Hydra (Hydra viridiisma)

subject:
Green hydra
Hydra viridissima
Population growth
Morphology
Landfill leachate

abstract: Harmony Landfill is a former industrial waste disposal site located adjacent to Harmony Creek in Oshawa, Ontario, Canada. During active disposal, from 1957 until 1980, approximately 1 million tonnes of waste were land-filled at the site. Although past environmental monitoring had indicated localized contamination of ground and surface waters, the current level of impact remained unclear. In order to determine the potential of Harmony Landfill leachate to affect aquatic organisms in Harmony Creek, chemical analysis of field samples and laboratory toxicity testing were performed. Chemical analysis was completed on water samples from Harmony Creek and surface leachate samples collected seasonally at Harmony Landfill. Toxicity tests were conducted using the model freshwater invertebrate Green Hydra (Hydra viridissima). Hydra were pulse-exposed for 24 hours to varying concentrations (0%, 3.2%, 10%, 32%, 100%) of monthly field-collected leachate samples diluted with laboratory water. Population growth, Hydra morphology and survival were recorded daily for 7 days. Results showed that creek waters generally had comparable analyte levels upstream and downstream of Harmony Landfill. Leachate samples contained iron, manganese and zinc at levels which may be toxic to aquatic invertebrates. Population growth was significantly inhibited compared to lab water (0%) controls at the 100% leachate concentration in December 2008 and July 2009. Hydra morphology (32% and 100%) and survival (100%) were also affected by the December 2008 leachate. Findings indicate that leaching is occurring at Harmony Landfill and that the leachate sampled and tested during this research program had the potential to negatively affect Green Hydra (Hydra viridissima).


title: Is multimodal care effective for the management of patients with soft tissue injuries of the shoulder? A systematic review of the literature

subject:
Shoulder impingement syndrome
Shoulder pain
Rotator cuff tendinitis
Multimodal care
Systematic review

abstract: Shoulder injuries are common and cause significant pain and disability. Individuals who consult clinicians for shoulder pain are typically treated with multimodal care. However, little is known about the effectiveness of multimodal care. This systematic review examines the effectiveness of multimodal care for soft tissue shoulder injuries. Five databases were systematically searched, 5885 articles were screened, and 19 were critically appraised. The best-evidence synthesis includes ten high-quality RCTs. For subacromial impingement syndrome, multimodal care leads to similar outcomes as sham therapy, shock-wave therapy, corticosteroid injections and surgery. For rotator cuff tendinitis, a multimodal program (acupuncture, dietary advice, and enzyme tablets) is more effective than conventional care (supervised exercise, soft tissue therapy, manual therapy, and placebo tablets). For non-specific shoulder pain, multimodal care may be more effective than waitlist, but leads to similar outcomes as exercise or corticosteroid injections. Future research is needed to determine the effectiveness of multimodal care.


title: Adaptive IEEE 802.15.4e LLDN scheduler for wireless network control systems

subject:
IEEE 802.15.4e LLDN
WNCS
Adaptive scheduler
LCVs

abstract:
An active area of research in the automotive research community is the stability of
Long Commercial Vehicles (LCVs) using active trailer steering and/or braking. These
LCVs rely on sensor data located across different regions of the tractor and trailers and compose the LCV. Communication of the sensor data to the Electronic Control Unit (ECU) of the active trailer system is performed through a conventional wired bus. The benefits of wireless communication for an LCV are improved flexibility, maintenance, elimination of physical socket connections and, reduction of weight related to the wires in the vehicle. In LCVs there is a natural demarcation point between the tractor and trailers where wireless communications can replace the wired communication bus. This thesis investigates the latency and throughput of wireless communication using IEEE 802.15.4 and IEEE 802.15.4e Low Latency Deterministic Network (LLDN) protocols for different sensor sampling rates in an LCV scenario and creates a guidelines for the system designers to select the right sensor sampling times. Furthermore, it proposes a new adaptive IEEE 802.15.4e LLDN algorithm that computes the optimal timeslot and superframe duration based on the sensor node data inter-arrival times to achieve the desired LCV controller latency that will exhibit stable behaviour. Simulation results confirm that this adaptive IEEE 802.15.4e LLDN algorithm can configure the IEEE 802.15.4e LLDN that present the best results for delay as well maximum throughput for a desired latency.


title: A narrative inquiry into the experience of a practical nursing graduate with private tutoring

subject:
Tutor
Nursing
Disability
Narrative inquiry

abstract: Disability studies are an established area of scholarship in education and this has been my passion for the last decade. Students living with disabilities in healthcare profession education (including nursing, personal support, occupational and physical therapy), as well as the use of professional tutors as an educational support among this population, is under researched. Throughout my practice as a professional health sciences tutor, I have wondered how this population of students experiences both one to one tutoring over time and educational accommodations. In this Narrative Inquiry (Clandinin & Connelly, 2000), my co-participant and I go on a journey together to explore how a graduate from an Ontario Registered Practical Nursing program with a diagnosed disability impacting her learning experienced individualized tutoring. Through a series of five semi-structured narrative interviews and self-reflection, the co-participant’s story was re-constructed and analyzed using the Narrative Inquiry three-dimensional space (temporality, sociality, and place). This Narrative Inquiry highlights the temporal connections of life events and how social conditions mutually shape and change personal conditions. Four narrative threads: barriers to access, stigmatization, individuality in education, and paradoxical conflicts among caring professions. It also highlights the importance of reflective practice, barrier-free inclusive education, and the need for further research into tutoring practice, education and policy. Tutors must establish a relationship that allows for exploration of context and building of a contextually-meaningful program, one in which learning is fostered.


title: Enhancing roll stability and directional performance of articulated heavy vehicles based on anti-roll control and design optimization.

subject:
Articulated heavy vehicle
LQR controller
Anti roll stability control
TruckSim
Genetic algorithm

abstract: This research presents an investigation to actively improve the rollover stability of articulated heavy vehicles (AHVs) during high speed manoeuvres using anti-roll control systems. A 3-dimensional (3-D) linear yaw/roll model with 5 degrees of freedom is developed. Based on this model a linear quadratic regulator (LQR) controller is designed to improve the rollover stability of a tractor/semi-trailer combination. A design optimization method for AHVs using genetic algorithms (GAs) and multibody vehicle system models is also presented. AHVs have poor manoeuvrability when travelling at low speeds on local roads and city streets. On the other hand, these vehicles exhibit unstable motion modes at high speeds, including jack-knifing, trailer sway and rollover. From the design point of view, the low-speed manoeuvrability and high-speed stability have conflicting requirements on some design variables. The design method based on a GA and a multibody vehicle dynamic package, TruckSim, is proposed to coordinate this trade-off relationship. To test the effectiveness of the design method, a tractor/semi-trailer combination is optimized using the proposed method. It is demonstrated that the proposed design method can be used for identifying desired design variables and predict performance envelopes in the early design stages of AHVs.

abstract: University of Ontario Institute of Technology


title: Investigation of dye-sensitized solar cell performance with single chirality semiconducting carbon nanotubes

subject:
Carbon nanotubes
DSSC
Chirality

abstract:
In this work, the performance, electrical transport, and optical properties of dye-sensitized solar cells (DSSCs) assembled with single-walled carbon nanotubes (SWNTs) of a single chirality in the photoanode were investigated.
Single-chirality carbon nanotubes (CNTs) allow a selection of band-gap and electron mobility. Separating a specific chirality from a mixture of carbon nanotubes remains challenging task.  Among separation techniques, one of the most promising is size-exclusion gel chromatography. Although SWNTs separated by this technique has been applied in bulk heterojunction solar cells and other basic electronics, no one has attempted to use this material in DSSCs.
Single-chirality carbon nanotubes allow adjustment of the Schottky barrier height at the  TiO2/CNT/FTO interface and the presence of single-chirality bundles increases electron diffusion in the photoanode.  Furthermore, chirality separated CNTs are expected to absorb less light than mixed chirality CNTs which results in better light absorption and electron injection into the TiO2.
Chiralities (6,5) and (7,3) have been separated using this technique and compared with mixed chiralities in a DSSC. Characterization includes I-V curves (performed in dark and light), quantum efficiency, and impedance spectroscopy.


title: Design of a fault tolerant control scheme based on sliding mode for Canadian supercritical water reactor

subject:
Canadian SCWR
Sliding mode control
Fault detection and isolation
Fault tolerant control

abstract: Canadian Super Critical Water Reactor (SCWR) is one of the Generation IV reactor types and possible heat source for co-hydrogen production through copper chlorine thermochemical cycle. To maintain the balance between the hydrogen production and electricity production effectively and to utilize the waste heat more efficiently, a well-designed control system for the Canadian SCWR is needed. The SCWR is a nonlinear and strongly coupled multiple-input multiple-output (MIMO) plant. Traditional controller design method, which divides the MIMO system into subsystems and then designs each controller separately, will not obtain satisfactory performance. To accomplish different control objectives of different system variables simultaneously, an integrated multivariable control strategy is needed. Furthermore, as a highly safety-critical system, it is desired that safe and stable performance of the plant can be maintained even in faulty situations. A sliding mode-based Fault Tolerant Control (FTC) scheme, which includes a robust multi-input multi-output controller, a Fault Detection/Isolation (FDI) module and a Fault Accommodation (FA) module, is designed for the overall Canadian SCWR plant in this study. The simulation results indicated that compared to previous control scheme design, better performance was obtained in terms of tracking speed, accuracy, decoupling capacity and control effort in the fault free case. In the faulty case, fault information can be detected and estimated. Acceptable tracking performance was maintained and the variation of steam temperature within design limit was guaranteed.


title: Parsing genetic models

subject:
Diagram understanding
Diagram detection
Visual illustrations
Bioinformatics
Object detection

abstract: Applications of computer vision have seen great success recently, yet there are few approaches dealing with visual illustrations. We propose a collection of computer vision  applications for parsing genetic models. Genetic models are a visual illustration often used in the biological sciences literature. These are used to demonstrate how a discovery fits into what is already known about a biological system. A system that determines the interactions present in a genetic model can be valuable to researchers studying such interactions. The proposed system contains three parts. First, a triplet network is deployed to decide whether or not a figure is a genetic model. Second, a popular object detection network YOLOvS is trained to locate regions of interest within genetic models using various deep learning training techniques. Lastly, we propose an algorithm that can infer the relationships between the pairs of genes or textual features present in the genetic model.


title: Automatic knobs-tuning for DB2 using deep reinforcement learning

subject:
Database tuning
Knob tuning
Deep reinforcement learning
DB2

abstract: Modern database management systems have hundreds of different configuration parameters (knobs) that control various aspects of how they behave and perform. These knobs must be properly tuned in order to maximize the performance of the database for a given query workload. Traditionally, database administrators would be responsible for database performance tuning. However, manual configuration tuning is a difficult process for humans, as there are hundreds of different inter-dependent knobs to be tuned. Different queries and workloads also benefit from configurations differently, there is no one single database configuration that can fit all scenarios. We propose BLUTune, a system to automatically produce effective knob configuration for IBM DB2. BLUTune utilizes deep reinforcement learning and features a unique transfer-learning approach to training which allows for fast learning. In experimental validation, BLUTune demonstrates its capability of producing effective configurations across differing sizes of the TPC-DS OLAP benchmark in a timely manner.


title: Energy, exergy and exergoeconomic analyses of gas-turbine based systems

subject:
Gas turbine
Brayton cycle
Energy
Exergy
Exergoeconomics
Efficiency
Optimization

abstract: Gas turbines are the primary technology used for the purpose of power generation nearly everywhere. In this thesis, the Makkah Power Plant, running on a Brayton cycle, is considered for analysis. The peak demand for electric power in the City of Makkah occurs in the middle of the day during the summer and is almost double the off-peak demand. The plant employs turbines of two world renowned manufacturers. However, there are many mechanical and electrical issues related to the overall insufficient operation of the plant. From the balancing of mass, entropy, energy, exergy and cost equations, a greater understanding of the systems as well as their efficiencies is achieved. The parametric study and plant optimization are performed to investigate the effects of the variation of specific input parameters such as fuel mass flow rate, air volume flow rate and compressor inlet air temperature, on the overall operating efficiency of the system. Through this study, the overall plant energetic and exergetic efficiencies are increased by 20% and 12% respectively with cooling down the compressor inlet temperature to 10oC. Furthermore, exergy and exergoeconomic analyses are conducted to obtain that the largest exergy destruction occurs in the combustion chamber, followed by the turbine. The optimization results demonstrate that CO2 emissions can be reduced by increasing the exergetic efficiency and using a low fuel injection rate into the combustion chamber. Finally, this study will assist efforts to understand the thermodynamic losses in the cycle, and to improve efficiency as well as provide future recommendations for better performance, sustainability and lessen environmental impact.


title: Revving up for the future: an inductive power transfer system geared for vehicular applications

subject:
Electric Vehicle
Inductive Power Transfer
Series-Series (SS) compensation
Power control
Efficiency maximization

abstract: Energized by the prospect of decluttering the charging infrastructure by severing the bulky power cords used to charge an Electric Vehicle (EV), an innovative technique to wirelessly charge an EV battery known as Inductive Power Transfer (IPT) has garnered widespread acceptance. This thesis introduces the design of an integrated stationary IPT system with an optimized power control algorithm and efficiency maximization to transfer power from a transmitter pad positioned on the ground and the receiver pad embedded under the chassis of an EV. Magnetic analysis for the charging coil architecture is facilitated via simulations in Ansys Maxwell. The power electronics design focuses on implementation of an H-bridge converter incorporating Series-Series (SS) compensation topology to utilize a novel control algorithm to prioritize battery charging operation. The system is validated through a simulation model in PSIM and a hardware-in-the-loop simulation in Typhoon HIL before hardware implementation and testing of the developed prototype.


title: An analysis of face matching accuracy and related variables: a meta-analysis and two follow-up studies

subject:
Face matching
Accuracy
Base rates of mismatch
Expression
Security

abstract: Face matching is used in many different transportation and policing situations and is an important last line of defense in security contexts such as the TSA. Despite how important this task is in ensuring security, no meta-analyses have been performed to find the average effect sizes of previously researched variables. To rectify this issue, I conducted a series of studies aimed at clarifying the field with regard to the factors important for influencing face-matching accuracy. Study one was a meta-analysis; studies two and three tested specific questions that arose from the meta-analysis. As expected, view, expertise, and feedback were found to be important; however, inconsistent with multiple reports, base rates of mismatch did not reach significance. A second study further examined base rates of mismatch to see if awareness of the base rate is necessary for the known low prevalence effect to occur. Results found that awareness mitigated the low prevalence effect instead of inducing it. A final study examined how expressions affect face matching accuracy. Participants were most accurate when evaluating photos showing neutral stimuli as opposed to expressive stimuli. The results of these studies provide information that can be used to increase face matching accuracy which is crucial as many security decisions rely on face matching and face matching is increasingly involved in legal decision making.


title: A framework for privacy-preserving data sharing in smart grid

subject:
Smart grid
Privacy
Security
Data sharing

abstract:
While smart grid introduces a lot of enhancements to the traditional power grid and improves managing and controlling consumers demands, it also introduces security and privacy issues. Therefore, failure to address them will hinder the flourish of smart grid.
In this thesis, we propose a novel framework for privacy-preserving data sharing in smart grid using a combination of homomorphic encryption and proxy re-encryption. The proposed framework allows distributed energy resources to be able to analyze the consumers data while preserving the consumers privacy. To the best of our knowledge, the proposed framework is first attempt to consider an important problem concerning data sharing in smart grid. Furthermore, in order to effectively collect consumer (or household) electricity consumption data, we also propose an efficient lightweight privacy- preserving data aggregation scheme, called ELPDA, for smart grid. The proposed scheme aims at resolving the power consumption data security and residential consumer privacy by employing one-time masking technique to protect consumers privacy while achieving lightweight data aggregation.
Moreover, we study the situation in which gateways aggregating consumers’ data become malicious. Then, we propose a security-enhanced data aggregation scheme for smart grid communications from a homomorphic cryptosystem, trapdoor hash functions and homomorphic authenticators. The distinctive feature of our scheme achieves data confidentiality and integrity against the malicious aggregator (e.g. gateway), meaning that the aggregator is not able to learn the privacy of users or corrupt the power consumption reports during the aggregation process.
In addition to the above schemes for smart grid upnlink communications, we propose an efficient and privacy-preserving scheme in order to protect smart grid in downlink communications. Specifically, we propose an efficient identity based signcryption, called EIBSC, providing privacy preservation in downlink communication for smart grids. The proposed scheme is characterized by employing the concealing destination technique on the tree-based network to protect consumer privacy in downlink communication. Furthermore, the proposed scheme employs identity based signcryption to efficiently achieve downlink message source authentication, data integrity and confidentiality. Additionally, compared to other identity-based signcryption schemes, the proposed scheme is more efficient in regards to computational overhead and ciphertext size. Furthermore, security analysis demonstrates that the proposed scheme is resilient against various security threats to smart grids.


title: A supervised machine learning-based framework to detect low-level fault injections in software systems

contributor:
Mahmoud, Qusay H.
Azim, Akramul

subject:
Attack detection
Fault injection attack
Low-level software fault injection
Machine learning
Software fault injection dataset

abstract: Fault injection attacks inject faults into system components, inducing abnormal software behavior. Software vulnerability analysis cannot prevent new attack vectors without software modifications. Attack detection methods utilize system-specific software features and unsupervised learning due to lack of labelled data. Unsupervised pattern recognition is vulnerable to false data injection, and Machine Learning algorithms such as Artificial and Recurrent Neural Networks are not feasible for resource-constrained software systems. Supervised detection of low-level attack effects presents a possible solution to these issues. This thesis introduces a supervised ML-based framework to detect low-level software fault injections consisting of labelled dataset generation using an instruction-level software fault injection tool to simulate attack effects. The framework is implemented on two software systems and the results demonstrate its feasibility. The thesis explores system-level threat detection due to simulated low-level attack effects and demonstrates that combining application data and software properties improves the low-level software fault injection prediction.


title: Compact integrated designs of microwave filters and antennas with dual-polarization

contributor:
Wang, Ying
Roy, Langis

subject:
Filter antenna integration
Dual-polarization
Dielectric resonator antennas
Microstrip antennas

abstract: Microwave antenna and filter circuits are key components in all types of communication systems. In order to achieve high compactness and high performance for next generation wireless networks, this thesis investigates the use of a material with a high dielectric constant (approximately 20) and low loss for integrated design of microwave filters and antennas. Two different filtering antenna designs in the 3.5 – 3.7 GHz frequency range are presented. A dual-mode waveguide filter is used in both designs, while a microstrip antenna is used for one design and a dielectric resonator antenna (DRA) is used for the other. Microstrip antenna and DRA are used due to their low-profile, ease of fabrication and light weight. The integrated designs are validated using full wave electromagnetic (EM) simulations, showing comparable performances. Both designs are compact, low loss, and have dual-polarization with good isolation, making them ideal for 5G mobile communication applications.


title: Experimental design, analysis and improvement of a Marnoch Heat Engine with heat recovery.

contributor:
Naterer, Greg F.
Dincer, Ibrahim

subject:
Marnoch Heat Engine
Heat recovery
Energy efficiency
Exergy efficiency
Transient heat transfer

abstract:
This research examines the prototyping of a Marnoch Heat Engine (MHE) and
conducts thermodynamic and heat transfer analyses of this heat engine with a waste heat
recovery system. The heat source for the MHE can be low grade heat (about 365 K).
During cold seasons an ambient temperature can be adequate for the heat sink to operate
the heat engine. When the ambient temperature is high, the system can be connected to a
dry cooler to achieve higher efficiency levels. A water/glycol mixture transfers heat from
the heat source into the hot heat exchangers and removes the heat from the cold heat
exchangers. Compressed dry air is used as the working fluid in the heat engine.
This thesis develops prototyping of the MHE with two different mechanical
configurations of the transmission system. Furthermore, thermodynamic analysis is
carried out to calculate the heat engine power output, as well as energy and exergy
efficiencies under various operational conditions. A heat transfer model is developed to
predict the transient temperature behaviours of the heat exchangers for different flow
regimes and temperatures. The results from the model are validated against the available
data in the open literature and then compared with experimental results from the present
MHE prototype. The average difference between the heat transfer model and the
measured data from the MHE prototype is about 10 K. Life cycle assessment is applied to
identify CO2 emissions of the MHE during the manufacturing and maintenance
processes. The heat source and heat sink temperatures for this case study are assumed to
be 281 K and 370 K, respectively. In a developed case study, it is found that the amount
of CO2 released as a result of manufacturing and maintenance of the system is about 52 g
CO2-quivalent per kWh.

Results from the exergoeconomic analysis are used to determine the required changes in MHE design parameters for the purpose of improving the cost effectiveness of the overall system. Energy and exergy efficiencies of the MHE are evaluated under various operating conditions. It is shown that the maximum exergy efficiency of the MHE reaches, at most, 18% of the Carnot efficiency. The maximum value of the exergoeconomic factor is found to be 0.45, and that the heat exchangers are the major sources of exergy destruction within the system. To improve the system performance, the major sources of heat and mechanical losses are identified and addressed. This research proposes four new heat exchanger designs that can be applied to future designs of the MHE units. The strength of the effect of each proposed design on the system performance is also discussed.


title: Characterization of nanopores with internal cavities for DNA manipulation using Langevin dynamics simulations

contributor:
de Haan, Hendrick
Waller, Ed

subject:
Nanopores
Langevin dynamics
Computational
Nanobiophysics

abstract:
A novel nanopore geometry is proposed, in which a larger internal cavity is
located inside a traditional nanopore. Polymer translocation through this geometry
is studied using coarse-grained Langevin dynamics. The most striking
result is that translocation time through the system is found to be minimal
for polymers of medium length: both longer and shorter chains take longer
to translocate. The length at which this occurs is named the critical length.
This phenomenon arises as a balance between the driving electric force field
and the entropic barrier that must be overcome in order for the polymer to exit
the internal cavity. More detailed characterization of the system over a range
of simulation parameters elucidate the physical mechanisms important to this
mechanism. Using these results, a simplified free energy model is constructed
and is solved analytically to predict the critical chain length as a function of
applied field strength and cavity size. Good agreement is recovered between
this theoretical model and numerical measurements over a range of parameters,
and bounds of applicability are discussed. Applications of this new nanopore
design are discussed.


title: Assessing the memorability of familiar vocabulary for system assigned passphrases

subject:
Authentication
System-assigned passphrase
Memorability
GPT-2

abstract: Text-based secrets are still the most commonly used authentication mechanism in information systems. Initially introduced as more secure authentication keys that people could recall, passphrases are tokens consisting of multiple words. However, when left to the choice of users, they tend to choose predictable natural language patterns in passphrases, resulting in vulnerability to guessing attacks. System-assigned authentication keys can be guaranteed to be secure, but this comes at a cost to memorability. In this study we investigate the memorability of system-assigned passphrases from a familiar vocabulary to the user. The passphrases are generated with the Generative Pre-trained Transformer 2 (GPT-2) model trained on the familiar vocabulary and are readable, pronounceable, sentence like passphrases resembling natural English sentences. Contrary to expectations, following a spaced repetition schedule, passphrases as natural English sentences, based on familiar vocabulary performed similarly to system-assigned passphrases based on random common words.


title: Starting the conversation: a phenomenological study exploring registered dietitian’s lived experience counseling children living with obesity and their families.

subject:
Registered dieticians
Phenomenology
Childhood obesity
Family
Lived experience

abstract:
This study was completed in order to gain an understanding of Registered Dietitian’s lived experiences counseling children living with obesity and their families.
Between November 2013 and March 2014, 8 Registered Dietitians participated in a telephone interview or online survey where they reflected upon their lived experience counseling children living with obesity and their families. A phenomenology of practice design was used to collect and analyze the data in order to determine the lived experience of Registered Dietitians who counsel children living with obesity and their families, and what resources and education prepare them to counsel this population. The findings confirm that Registered Dietitians’ goal is to provide the necessary knowledge and resources to the families so they are able to make sustainable healthy lifestyle changes. To better their practice they would like a physical activity component in their education, more resources in family counseling, and motivational interviewing training.


title: Moving towards enhancing playtesting reports through data visualization

subject:
Data visualization
Game User Research
Biometrics
Human Computer Interaction
Video game development

abstract: Playtesting is a key component in the game development process aimed at improving the quality of games through gameplay data collection and identification of design issues. Visualization techniques are currently being employed to help integrate quantitative and qualitative data. However, two existing challenges are to determine the level of detail to be presented to developers based on their needs and to effectively communicate the collected data so informed changes can be reached. This thesis looks at investigating the effectiveness of using aggregated visualizations with four alternate visual designs to communicate playtesting data of multiple sources. To evaluate the visualizations in terms of their effectiveness in assisting developers in utilizing playtesting data, I present a study involving a semi-structured interview with professional game developers. The results provide an important contribution to the fields of Games User Research and  Human-Computer Interaction towards identifying areas of improvement in the portrayal of gameplay data.


title: Metal-free methodology for the preparation of ynones using potassium alkynyltrifluoroborates and its application to the synthesis of natural products

subject: Methodology Synthesis Boron Metal-free Ynone

abstract: A straightforward procedure for the preparation of ynones from potassium alkynyltrifluoroborate salts and acyl chlorides or anhydrides has been developed. The one-pot reaction is advantageous in that it does not require exclusion of air or water, is operationally simple, has broad substrate scope, and proceeds rapidly under mild conditions in the presence of a Lewis acid. 2,6-dimethoxy substituted anhydrides afford the corresponding mono-demethylated o-alkynoylphenol precursors of aurone and flavone natural product scaffolds in good yields. A variety of flavones were obtained via 6-endo cyclization of o-alkynoylphenol intermediates in the presence of trifluoromethanesulfonic acid (TfOH). Cesium carbonate was discovered to promote the rapid 5-exo cyclization of o-alkynoylphenols to form aurone products in excellent yields.


title: Design and validation of active trailer steering systems for articulated heavy vehicles using driver-hardware-in-the-loop real-time simulation

subject:
Active trailer steering
Articulated heavy vehicles
Driver-hardware-in-the-loop
ISO-14791
Model reference adaptive control

abstract: To improve the low-speed maneuverability and high-speed lateral stability of Double Trailer Articulated Heavy Vehicles (DTAHVs), an Active Trailer Steering (ATS) system has been designed. To date, investigations on ATS systems are mainly focused on numerical simulations. To advance this research towards real-world applications, a Driver-Hardware-In-the-Loop (DHIL) real-time simulation platform is developed for the design and validation of ATS system for DTAHVs. The real-time simulation results derived under the emulated low-speed path-following test maneuvers demonstrate the effectiveness of the DHIL platform and the distinguished features of the ATS system. This thesis examines the applicability of two single lane-change test maneuvers specified in ISO-14791 for acquiring rearward amplification, which is an important indicator for the high-speed lateral stability. Simulation results indicate that the closed-loop test is more applicable for DTAHVs with ATS systems. This thesis also proposes a new ATS controller using the model reference adaptive control technique. Numerical simulations illustrate that the proposed MRAC controller can achieve robust performance under the variations of vehicle forward speed and trailer payload.

abstract: University of Ontario Institute of Technology


title: Mass transport in the cathode electrode of a molten carbonate fuel cell

subject:
molten carbonate fuel cell
MCFC
electro-chemical energy conversion
molten salt electrolyte

abstract:
A molten carbonate fuel cell (MCFC) is an electro-chemical energy conversion technology that runs on natural gas and employs a molten salt electrolyte. In order to keep the electrolyte in this state, the cell must be kept at a temperature above 500 C, eliminating the need for precious metals as the catalyst. There has been only a limited amount of research on modelling the transport processes inside this device, mainly due to its limited ability for mobile applications.
In this thesis, three one-dimensional models of a MCFC are presented based on different types of diffusion and convection. Comparisons between models are performed so as to assess their validity. Regarding ion transport, it is shown that there exists a limiting case for ion migration across the cathode that depends on the conductivity for the liquid potential. Finally, an optimization of the diffusivity across the cathode is carried out in an attempt to increase the cell performance and its longevity.


title: Dosimetric characterization of a miniature x-ray source for biophysics studies

subject:
Tritium
Mini-x
Relative biological effectiveness
Beam-characterization

abstract:
Tritium is a low energy beta emitter that is found in abundance at CANDU nuclear power plants and is a cause of concern since it accounts for roughly thirty three percent of the total occupational exposure of nuclear workers. According to current standards, the radiation weighting factor for all electrons irrespective of their energies is 1. However, there is some evidence suggesting that this factor for low energy electrons could be more than 1. Due to the complexities associated with handling tritium in a liquid or gaseous state alternate arrangements to simulate tritium radiation are investigated. Therefore, in this project it is proposed to use a miniature X-Ray source (Mini-X) to simulate tritium radiation and characterise these low energy X-Ray beams with the aim of investigating the relative biological effectiveness of low energy electrons.
The scope of this study is to design and characterize low energy X-Ray beams, suitable for biophysical experiments using Gafchromic’s XR-QA2 radiochromic film and Standard Imaging’s A-20 ionization chamber. To safely carry out the characterization experiments a dual layered safety shielding was constructed and parameters including beam dimensions, air-kerma and dose to tissue values from the Mini-X were explored. Lastly, a cross calibration curve between an optically stimulated luminescent dosimeter (nanoDots) and A-20 ionization chamber was established, with an aim to use nanoDots for a proposed future biophysical experiment.
It was found that the Mini-X produced a flat beam profile at distances up to 12.7 cm from the source. In addition, air-kerma values of 11.56 and 6.442 cGy/s could be obtained at 2.54 cm and 5.08 cm respectively with operating parameters of 20 keV and 75 μA. It was also established that there is no substantial difference between air-kerma and dose to tissue values for the X-Ray beams studied. For future work, a biophysical experiment would be carried out using fish eggs where the impact of the Mini-X X-Ray beams on egg hatchability and embryonic mortality would be measured.


title: One-dimensional single phase natural circulation model of FLiNaK in Molten Salt Loop

subject:
Molten salt
FLiNaK
Natural circulation
Gen IV reactor
Molten salt loop

abstract: This work studied a coolant for a molten salt type reactor in terms of a natural circulation behavior. A natural circulation model using MATLAB was developed. This model is for the Molten Salt Loop currently under development at University of Ontario Institute of Technology to investigate aging related degradation effects and thermal storage applications of FLiNaK. The model’s purpose is to help design the flow loop and future experiments. Generation IV reactors were compared to provide an overview of new reactor concepts with an in-depth review of the Molten Salt Reactor MSR type. The molten salt history, design, and application were discussed. A review of thermophysical properties of different salt coolants is performed to understand the variation of cooling capability. The model’s results were compared to different fluid types to verify the trends. This gave a baseline upon which to refer when experimental results are ready and thus guide future research into molten salt studies.


title: Design and analysis of active aerodynamic control systems for increasing the safety of high-speed road vehicles

subject:
Road vehicles
Lateral stability
Active safety systems
Aerodynamic control
Sliding mode control

abstract: The lateral stability and the safety of road vehicles is dependent on the vehicle design and operating conditions. Under operating conditions such as slippery roads, high lateral acceleration and tight cornering, the forces and torques due to the interactions between the tire and road may be saturated. Various active safety systems have been proposed and developed to mitigate these concerns but they all work based on the manipulation of tire forces. Thus, the capability of the current active safety systems cannot go beyond the performance limitation determined by the interactions between the tire and road. On the other hand, at high speeds, significant downforce can be generated by employing aerodynamic wings on the vehicle body to enhance its road holding ability. A split rear wing is proposed to control the aerodynamics of high-speed road vehicles to closely manipulate the dynamics of the vehicle. A nonlinear vehicle model is derived to simulate the vehicle’s lateral dynamics and an airfoil with a high lift to drag ratio is used to design the rear wing. A sliding mode control technique is used to design the active aerodynamic controller to achieve the objective of tracking the desired steady-state yaw rate. The selection of the control technique and the control objective is shown to be comprehensive and satisfactorily improve the handling performance. The controller design is validated using co-simulation implemented in the combined CarSim-MATLAB/Simulink simulation environment. Simulation results demonstrate that active aerodynamic control improves the lateral stability of the vehicle and that the improvement is more pronounced as the vehicle forward speed increases. The enhancement in lateral performance and road holding capability is also presented.