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Biases in adults’ truth and lie judgments of Black children’s statements: An examination of anti-Black attitudes and unawareness of racial inequalities
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Science in Experimental and Applied Psychology, University of Regina. viii, 85 p.A growing body of literature has sought to examine factors that impede adults’ abilities to detect children’s lies. The current study extends previous research that found that adults demonstrate a racial bias when evaluating statements made by children and that these judgements are related to their motivations to respond without prejudice. The goal of the current study was to explore whether adults’ veracity judgments of Black and White children’s statements differ as a function of adults’ anti-Black attitudes and their unawareness of racial privilege, institutional discrimination, and racial issues within society. Participants reviewed fictitious transcripts of a child who denied committing a misbehaviour, judged whether they believed the child to be lying or telling the truth, and completed questionnaires assessing their prejudicial attitudes. Consistent with previous research, adults displayed a general truth bias when judging the veracity of children’s statements. The strength of this truth bias was dependent on the race of the child, such that Black children were more likely to be labelled as telling the truth compared to White children. After controlling for participants’ race and overall willingness to label a child as truthful, participants’ prejudicial attitudes predicted their deception scores for Black children, such that participants with lower prejudicial attitude scores rated Black children to be more honest compared to participants with higher prejudicial attitudes. The results of this study carry the potential to enhance our understanding of cross-race deception detection and may help identify factors that interfere with our ability to accurately detect children’s lies.Studentye
Development of task specific ionic liquids incorporated porous sorbents for post-combustion CO2 capture
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Process Systems Engineering, University of Regina. xvii, 166 p.Amino functionalized ionic liquids (AAILs), also known as task-specific ionic liquids (TSILs),
have demonstrated CO2 capture ability similar to amines while maintaining ionic liquid properties
such as low regeneration energy, volatility, and thermal stability. However, high synthesis
costs and viscosity prevent their broad usage in CO2 capture technologies. Recently discovered
porous materials like metal-organic frameworks (MOFs) and ordered mesoporous silica have
stimulated scientists’ interest in CO2 capture applications. However, these materials have
limited CO2 absorption and poor CO2/N2 selectivity, particularly at post-combustion CO2
capture conditions (0.15 bar). Immobilizing TSILs in solid pores to boost CO2 capture is an
innovative way to address the drawbacks of both TSILs and porous materials.
This study incorporated 1-ethyl-3-methylimidazolium [Emim] cations with Glycine [Gly]
and Alanine [Ala] as reactive Amino Acid (AA) anion, resulting in [Emim][Gly] and [Emim]
[Ala]. Three porous solid supports were used, metal-organic-framework (MOF-177), zeolitic
imidazolate framework (ZIF-8), and ordered mesoporous silica (MCM-48)
leading to TSILs@MOF/ZIF/MCM composites. TGA and XRD measurements were
performed to determine the composites’ thermal and structural stability. The specific surface
area and the pore volume distribution were determined by using N2 adsorption-desorption
isotherms at 77 K. CO2 adsorption isotherms were measured using an intelligent gravimetric
analyzer (IGA) at three temperatures (303, 313, and 323 K), and N2 adsorption isotherms were
measured at 313 K for a pressure range of 0.1 to 10 bar, for all composites and pristine solids.
The CO2/N2 selectivities were computed using the CO2 and N2 adsorption isotherms. Adsorption
isotherms were modeled by the Dual-Site Langmuir (DSL) model, and the isosteric
enthalpy of adsorption was computed. [Emim][Gly]@ZIF-8 composites demonstrated
excellent improvements in CO2 uptake and CO2/N2 selectivity at 30 wt. % loading.
CO2 uptake was 10 times higher than in pure ZIF-8 at 0.1 bar and 303 K, and selectivity
improved to 28 from 5 at 0.1 bar and 313 K. At 20 wt. % loading, AAILs-encapsulated
composites surpassed pure MOF-177 in CO2 uptake by a factor of 3. The ideal AAIL loading
was 20 wt. % and increasing the loading to 30 wt.% did not increase CO2 uptake for the
AAILs@MOF177 composite. [Emim][Gly]@MCM-48 and [Emim][Ala]@MCM-48 composites
enhanced CO2 uptake 10-fold and CO2/N2 selectivity to 17 from 2 at 0.1 bar for 40 wt. %
loading.
The improved CO2 capacity and selectivity can be attributed to the formation of C-N bonds
between CO2 and the -NH2 functional group, as suggested by the isosteric enthalpy of adsorption.
In addition, blended systems of amine (PZ) with 1-ethyl-3-methylimidazolium acetate
[Bmim][Ac] have the potential for high CO2 capture capabilities like TSILs without inheriting
TSIL limitations such as high synthesis cost and viscosity. CO2 absorption was unaffected by 30
wt. % IL in the aqueous PZ, while 60 wt. % IL greatly increased it. Furthermore, this aqueous
blended system (PZ+IL+H2O) and a second non-aqueous system of ethylene glycol (EG) mixed
with MEA were examined as slurry systems in which porous solid ZIF-8 was suspended. Nonaqueous
slurry systems outperformed aqueous slurry systems, which could be attributed to the
collapse and/or pore filling of ZIF-8 in aqueous systems as evident from the TGA and XRD
analysis of the recovered ZIF-8.
These research results can be used to build sorbents with superior qualities to address
environmental concerns since they shed light on the synthesis, structure, and sorption capacity of
these innovative composite materials.Studentye
Application of data-driven methods in water resources engineering – case studies
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Environmental Systems Engineering, University of Regina. ix, 91 p.Water resources engineering stands at the forefront of sustainable water management, facing
challenges that necessitate innovative solutions. This thesis explores the integration of data-driven
methods into the field, with a dual focus on predicting Maximum Scour Depth around Piers under
Ice-covered Conditions (MSDI) and enhancing Water Quality Index (WQI) predictions.
In addressing the first objective, MSDI, the study utilizes three data-driven methods—M5, PSO,
and GEP—to predict scour depth around piers under ice-covered conditions. A meticulous dataset
preparation process precedes model development, followed by rigorous evaluation and sensitivity
analysis. The proposed solution framework not only advances academic understanding but also
provides practical insights for engineers and practitioners in water resources engineering,
addressing a critical gap in predicting scour depth under ice-covered conditions.
The second objective focuses on WQI, a key parameter for water quality assessment. The study
gathers a comprehensive dataset from the North Saskatchewan River and employs the NFS-WQI
method. Feature selection and algorithm evaluation, including M5, PSO, DE, GEP, and MARS,
enhance predictive capabilities. The refined predictive tools highlight crucial determinants like
Dissolved Oxygen and pH, contributing practical implications for environmental management.
In conclusion, the thesis emphasizes the significance of data-driven methods in water resources
engineering, offering a robust and efficient approach to modeling complex systems. The
integration of these methods complements traditional empirical models, providing a nuanced
perspective crucial for decision-makers in water resource management. The comprehensive
insights derived from MSDI and WQI studies pave the way for innovative solutions and adaptive
strategies in the face of evolving water-related challenges. As the field continues to evolve, the
application of data-driven methods becomes increasingly imperative for sustainable water
utilization and management.Studentye
Structural analysis and fatigue prediction of harrow tines used in Canadian prairies
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Industrial Systems Engineering, University of Regina. xiii, 119 p.Canadian prairies are renowned for their agricultural contribution to the global food market, where harrow tine is a critical component of agricultural equipment used for soil preparation and weed control before crop cultivation. Unfortunately, during operation, these tines are exposed to repetitive cyclic loading, which eventually causes fatigue failure. Commercially available three different harrow tines named 5-1895, 5-2709, 5-2776 undergo an experimental fatigue evaluation and are validated through a numerical approach using Finite Element Analysis (FEA). After that, fatigue life estimation for different deflections under different circumstances in the real field was determined where 5-2676 showed ground-breaking life compared with others. The results of the study showed that the fatigue life is highly dependent on geometry, number of coils, pitch angle, leg length, and coil diameter. 0.354 HT model resembles 5-2776 developed to investigate the effect of wire diameter. For this reason, the experimental SN curve for ASTM A229, Class I was developed utilizing the fatigue bending test. Following this, a comparative study between six harrow tine models was analyzed based on their harrowing ability against identical deflections. This study also identified critical locations of stress concentration, which could be used to optimize the design of the tines to improve their fatigue life. Experimental fractured surfaces went through morphological investigation. This research has an impeccable impact on prairies’ agricultural acceleration by saving time and unpredictable fatigue failure often faced by farmers through designing more reliable and durable harrow tines, which can reduce agricultural maintenance costs and increase efficiency.
Keywords: Fatgue failure, Harrow Tine, life estimation, S-N curve, ASTM A229.Studentye
Outcomes of transdiagnostic internet-delivered cognitive behavioural therapy tailored to public safety personnel: A longitudinal observational study
No full textFirst responders and other public safety personnel (PSP) experience high rates of mental health problems and face barriers to accessing mental healthcare. Internet-delivered cognitive behavioural therapy (ICBT) is an effective and accessible treatment for various mental health concerns. Canadian PSP report favorable attitudes toward ICBT, and preliminary outcomes demonstrate that they benefit from it. Expanding on this research, the current study consisted of a longitudinal observational study of 560 Canadian PSP who participated in ICBT. It was designed to assess the longer term effectiveness of ICBT and moderators of outcomes by gender, linguistic and occupational group, and years of occupational experience. We evaluated symptom change at 8, 26, and 52 weeks post-enrollment, and results among PSP who had elevated clinical scores, showed large reductions (Hedges’ g) in symptoms of depression (g = 1.3), anxiety (g =1.48), posttraumatic stress (g =1.24), panic (g =1.19), and anger (g =1.07) and moderate reductions in symptoms of social anxiety (g =.48–.56). Moderator analyses revealed modest differences in pre-treatment symptoms among certain groups but no group differences in symptom change over time. Clients showed good completion of treatment materials and reported high treatment satisfaction. The results suggest further study of ICBT tailored to PSP is warranted, including evaluating ICBT tailored for PSP in other countries.This research was conducted by PSPNET, which is funded by the Canadian Government’s Ministry of Public Safety and Emergency Preparedness
Within-person variability and own-age bias
No full textA Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Bachelor of Arts (Honours) in Psychology, University of Regina. 29 p.The own-age bias is the finding that memory is better for faces that are similar in age to the rememberer than other-age faces. This experiment investigated whether exposure to increased variability when learning faces reduces own-age bias in remembering those faces. Previous research suggested that own-age faces are remembered better than other-age faces because they are learned on an individual level instead of a categorical level. As such, a manipulation that promotes individuation, such as exposure to high within-person variability, should reduce own-age bias. Previous research employed various methods to encourage individuation of other-age faces and found mixed results. I hypothesized that if high variability encourages individuation, then own-age bias should be reduced when faces are learned in a high variability context. To test this, participants were randomly assigned to three between-subjects learning conditions a) no-variability b) low-variability, c) high-variability, and two within-subjects conditions a) own-age, b) other-age. Face recognition was tested using a “seen” or “not seen” task. Similar to previous research, individuals were more accurate at recognizing own-age faces than other-age faces. Accuracy for both own- and other-age faces was best for those who trained with high variability images. Although not significant, the results suggested that own-age bias may actually have been larger for faces seen with high variability
Beta-delayed proton emission of magnesium-20 and the RCMP silicon detector array
No full textA Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Science in Physics, University of Regina. xxiii, 123 p.In 2011, experiment e09024 was performed in National Superconducting Cyclotron
Laboratory(NSCl) located at Michigan State University from Michigan state. The
goal was to investigate delayed particle emission for isotopes near proton drip line.
The main secondary beam was ²²Si while other exotic beam such as ²⁰Mg,²²Al,²³Si
was also produced. The delayed particle emission from ²⁰Mg is of particular interest
in this thesis and has been studied in details. In 2018, Dr.Gwen Grinyer's group
at University of Regina started constructing a Silicon Detector Array named Regina
Cube for Multiple Particle(RCMP) used for studying delayed particles at proton drop
line with high resolution and high solid angle coverage. The detector is designed to
be placed inside GRIFFIN chamber located at TRIUMF cyclotron facility. GRIFFIN
chamber designed by GRIFFIN collaboration consists of 16 High Purity Germanium
detectors with 8 fast timing LaBr3 used for studying gamma rays. It is a high effociency
detector chamber with BGO shielding for Compton suppression. The combination
of the two could provide more detailed study of nuclear structure for isotopes near
proton drip line. The detector has been deployed in 2024 and a new experiment
on ²⁰Mg S2232 is being scheduled during 2024 summer. In this thesis, I will be
presenting analysis of ²⁰Mg from experiment e09024 with development and testing of
RCMP detector array and experiment S2232.
Key words: Proton Drip line,Beta-delayed, NSCL, TRIUMF, RCMP, GRIFFINStudentye
A study of drag‐and‐drop query refinement and query history visualization for mobile exploratory search
No full textWhen undertaking complex search scenarios, the underlying information need
cannot be satisfied by finding a single optimal resource; instead, searchers need
to engage in exploratory search processes to find multiple resources by itera-
tively revising and reformulation their queries. This process of query refinement
is particularly challenging when using a mobile device, where typing is difficult.
Furthermore, in mobile search contexts interruptions can lead to searchers los-
ing track of what they were doing. To address these challenges, we designed a
public digital library search interface for mobile devices that includes two novel
features: drag-and-drop query refinement and query history visualization. To
assess the value of this interface compared to a typical baseline, we conducted a
controlled laboratory study with 32 participants that included pursuing complex
search scenarios, being interrupted in the midst of the search, and resuming the
search after the interruption. While participants took more time, they generated
longer queries and reported positive subjective opinions about the usability of
the exploratory search and task resumption features, along with a greater
increase in certainty. These findings show the value of leveraging new touch-
based interaction mechanisms within mobile search contexts, and the benefits
that visualization can bring to supporting search task resumptionNatural Sciences and Engineering
Research Council of Canada,
Grant/Award Number: ALLRP558319-2