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Reinforcement Learning Based Resource Allocation for Energy-Harvesting-Aided D2D Communications in IoT Networks
Get PDFIt is anticipated that mobile data traffic and the demand for higher data rates will increase dramatically as a result of the explosion of wireless devices, such as the Internet of Things (IoT) and machine-to-machine communication. There are numerous location-based peer-to-peer services available today that allow mobile users to communicate directly with one another, which can help offload traffic from congested cellular networks. In cellular networks, Device-to-Device (D2D) communication has been introduced to exploit direct links between devices instead of transmitting through a the Base Station (BS).
However, it is critical to note that D2D and IoT communications are hindered heavily by the high energy consumption of mobile devices and IoT devices. This is because their battery capacity is restricted. There may be a way for energy-constrained wireless devices to extend their lifespan by drawing upon reusable external sources of energy such as solar, wind, vibration, thermoelectric, and radio frequency (RF) energy in order to overcome the limited battery problem. Such approaches are commonly referred to as Energy Harvesting (EH) There is a promising approach to energy harvesting that is called Simultaneous Wireless Information and Power Transfer (SWIPT).
Due to the fact that wireless users are on the rise, it is imperative that resource allocation techniques be implemented in modern wireless networks. This will facilitate cooperation among users for limited resources, such as time and frequency bands.
As well as ensuring that there is an adequate supply of energy for reliable and efficient communication, resource allocation also provides a roadmap for each individual user to follow in order to consume the right amount of energy. In D2D networks with time, frequency, and power constraints, significant computing power is generally required to achieve a joint resource management design. Thus the purpose of this study is to develop a resource allocation scheme that is based on spectrum sharing and enables low-cost computations for EH-assisted D2D and IoT communication.
Until now, there has been no study examining resource allocation design for EH-enabled IoT networks with SWIPT-enabled D2D schemes that utilize learning techniques and convex optimization. In most of the works, optimization and iterative approaches with a high level of computational complexity have been used which is not feasible in many IoT applications. In order to overcome these obstacles, a learning-based resource allocation mechanism based on the SWIPT scheme in IoT networks is proposed, where users are able to harvest energy from different sources. The system model consists of multiple IoT users, one BS, and multiple D2D pairs in EH-based IoT networks. As a means of developing an energy-efficient system, we consider the SWIPT scheme with D2D pairs employing the time switching method (TS) to capture energy from the environment, whereas IoT users employ the power splitting method (PS) to harvest energy from the BS. A mixed-integer nonlinear programming (MINLP) approach is presented for the solution of the Energy Efficiency (EE) problem by jointly optimizing subchannel allocation, power-splitting factor, power, and time together. As part of the optimization approach, the original EE optimization problem is decomposed into three subproblems, namely: (a) subchannel assignment and power splitting factor, (b) power allocation, and (c) time allocation. In order to solve the subproblem assignment problem, which involves discrete variables, the Q-learning approach is employed.
Due to the large size of the overall problem and the continuous nature of certain variables, it is impractical to optimize all variables by using the learning technique. Instead dealing for the continuous variable problems, namely power and time allocation, the original non-convex problem is first transformed into a convex one, then the Majorization-Minimization (MM) approach is applied as well as the Dinkelbach.
The performance of the proposed joint Q-learning and optimization algorithm has been evaluated in detail. In particular, the solution was compared with a linear EH model, as well as two heuristic algorithms, namely the constrained allocation algorithm and the random allocation algorithm, in order to determine its performance. The results indicate that the technique is superior to conventional approaches. For example, it can be seen that for the distance of m, our proposed algorithm leads to EE improvement when compared to the method such as prematching algorithm, constrained allocation, and random allocation methods by
about 5.26\%, 110.52\%, and 143.90\%, respectively.
Considering the simulation results, the proposed algorithm is superior to other methods in the literature. Using spectrum sharing and harvesting energy from D2D and IoT devices achieves impressive EE gains. This superior performance can be seen both in terms of the average and sum EEs, as well as when compared to other baseline schemes
Effect of enzyme hydrolysis of lentil and chickpea protein isolates on their physicochemical, functional properties and protein quality
Get PDFThe overarching goal of this research was to investigate the effect of enzyme hydrolysis of lentil (LPI) and chickpea protein isolates (CPI) using varied levels of hydrolysis to improve the functional properties and protein quality. Initially LPI and CPI were hydrolysed using trypsin to achieve degrees of hydrolysis (DH) at 5%, 10%, 15% and 20% respectively. The protein contents of CPI and LPI hydrolysates were in the range of 69% – 73% and 80% – 83% respectively. The lipid contents of CPI and LPI hydrolysates were in the range of 15% – 17% and 1.5% – 2.0% respectively. The physicochemical properties were examined for each hydrolysed protein preparation. The surface charges of CPI and LPI hydrolysates were decreased by 3.3 – 7.7 mV at pH 7.8 and were increased by 6.5 – 9.7 mV at pH 4.5. The surface hydrophobicity of CPI and LPI was increased by 1.1 – 2.4-times relative to the untreated protein isolate at pH 7.8. At pH 4.5, it was observed higher increases in surface hydrophobicity by up to 3.3-times. The surface and interfacial tension showed no significant difference with hydrolysis at either pH or protein isolates. FTIR analysis was performed to study the relative spectral weights of β-sheet, β-turn, α-helix, A1 and A2 residues. The results showed significant changes in the relative spectral weights with increase in hydrolysis when compared to the untreated isolates. SDS-PAGE and capillary gel electrophoresis showed that the hydrolysis process broke down high molecular weight protein molecules into small molecular weight protein molecules. The functional properties were studied to identify the suitability of enzymatic treatments for modification of protein isolates for food applications. The solubility of CPI and LPI increased after hydrolysis by 10 and 30-times. The emulsion stability of CPI and LPI at pH 7.8 increased by 2% after hydrolysis whereas at pH 4.5 it declined. The foaming capacity and stability of CPI decreased with hydrolysis, whereas LPI hydrolysis increased them both at pH 7.8 and 4.5. Water holding capacity of CPI and LPI did not change with hydrolysis whereas oil holding capacity showed significant increase. The protein quality of the untreated and hydrolysed protein isolates was also analysed. The limiting amino acid for both CPI and LPI was found to be tryptophan. The limiting amino acid score was found to improve from 0.62 to 0.71 in the case of CPI proteolysis and decreased to 0.37 for LPI. There was no significant increase or decrease in the in vitro protein digestibility (IVPD). In vitro protein digestibility corrected amino acid score (IVPDCAAS) of untreated LPI, and CPI was decreased from 52% to 32% for LPI and increased to 60% in case of CPI. Overall, enzymatic hydrolysis increased surface hydrophobicity and zeta potential, and improved functional properties in solubility, emulsion stability, oil holding capacity and surface properties. Meanwhile the foaming properties and water holding capacity are negatively affected. Qualitative analysis of flavour compounds in the chickpea and lentil isolates showed the presence of various off-flavour components including aldehydes, alcohols and ketones. Enzyme hydrolysis is a type of protein modification which could improve the functional and nutritional properties for a value-added protein ingredient. These changes suggest that the enzymatic hydrolyzed protein isolates could be applied into food emulsification food applications
Effects of Neonicotinoid Exposure on Anti-predator Behaviour and Learned Recognition of Novel Predator Odour of Larvae Lestes spp. (Odonata: Zygoptera)
Get PDFNeonicotinoids are widely used water-soluble neurotoxic insecticides. The effects of these
insecticides on non-target aquatic organisms have become a major environmental concern since
they affect both pests and non-target insects. Along with lethal effects, these insecticides could
cause visual and chemoreception impairment. This can lead to behavioural alterations in aquatic
organisms by disrupting the sensory systems used for detecting predators, thereby affecting antipredator behaviours. Therefore, in this thesis, I investigated the effect of imidacloprid, a
neonicotinoid insecticide, on the anti-predator response and learned recognition of novel predator
odour in damselfly larvae (Lestes sp). In the first experiment (chapter 2), damselfly larvae were
exposed to water contaminated with a series of concentrations (0.0μg/L, 0.1μg/L, 1.0μg/L, and
10.0μg/L) of imidacloprid and the change in number of feeding bites performed after injecting a
conspecific damage-released alarm cue solution and a predator kairomone solution was observed
and recorded on day 2, 5, and 10. On days 2 and 5, both the control and 0.1μg/L groups showed
appropriate anti-predator behaviour to alarm cues and predator odour, but this was not the case
for damselflies exposed to 1.0μg/L. By day 10, larvae in the 1.0 and 10.0μg/L groups no longer
responded to alarm cues and all exposure groups ceased responding to predator odour. In the
second experiment (chapter 3), I investigated the effect of exposure to a series of concentrations
of imidacloprid on learned recognition of predatory stimuli by damselfly larvae. Damselflies
were conditioned to recognize risk by exposing them to zebrafish odour (a novel odour)
combined with conspecific damage-released alarm cues or control of dechlorinated water. Larvae
in the control group learned to respond to the predator odour based on their prior conditioning
with alarm cues but not water. Learning of predator odour also occurred for larvae in the 0.1μg/L
treatment group but failed for individuals exposed to the higher concentrations of 1.0μg/Land
10.0μg/L. In the third experiment (chapter 4), I exposed damselfly larvae to imidacloprid (at an
initial pulse solution of 3.0μg/L and reaching a final concentration of 0.01μg/L) during the
conditioning period and evaluated the effect on learned recognition of novel predatory stimuli.
Damselflies were conditioned to recognize risk by exposing them to zebrafish odour with true
conditioning (alarm cue + predator odour) with or without imidacloprid and another group was
given sham conditioning (water + predator odour) with or without imidacloprid exposure. Larvae
given true conditioning without imidacloprid exposure correctly learned to recognize theiii
predator odour as a threat, while larvae given sham conditioning, and those exposed to
imidacloprid, failed to learn to respond to the predator odour. Overall, this study highlights that
acute and chronic exposure to imidacloprid at both environmental relevant and higher
concentrations impairs the anti-predator response to conspecific alarm cues and predator odour
by damselfly larvae. Further, this study demonstrates that imidacloprid affects learned
recognition of novel predator odour by damselfly larvae with the interaction between chemical
cues and imidacloprid potentially playing a key role in this impairment
Analysis of Microplastic Sources in the South Saskatchewan River and Selected Saskatoon Storm Ponds
Get PDFDue to their widespread presence in all ecosystems, microplastics have been classified as significant persistent environmental contaminants. Aquatic organisms' reproductive cycles, access to energy, and growth may all be adversely affected by microplastics in water bodies. As a result, it is important to identify the origins and quantities of microplastic in significant Saskatchewan waterways, particularly the South Saskatchewan River, which supplies water to more than 50% of the province's residents for a variety of uses. In this study, we used Raman micro-spectroscopy to examine the compositions and loadings of microplastics in samples taken from three storm ponds in the City of Saskatoon and seven sites along the South Saskatchewan River. Microplastics were identified in all river and storm pond samples with the mean concentrations of 4.43 ± 2.88 m-3 and 6.44± 3.62 m-3 respectively. Although the small sample size and large variability in the mean microplastics concentrations between samples limits meaningful statistical analysis, our results suggest that the mean microplastics load at Miry creek (12.00 ± 9.12 m-3) is higher compared to 3.18 ± 3.00 m-3 for all other river samples, indicating Diefenbaker dam may be acting as a sink for microplastics along the waterways. Fibers dominate the morphology class of microplastics recovered, while polymers from polyethylene terephthalate (PET), polypropylene (PP), and polystyrene (PS) were the major microplastics chemically identified among the samples. Particle contributions from both dyed and undyed natural fibers were also analyzed. This study represents the first exploration of microplastic levels in the South Saskatchewan River and selected Saskatoon’ storm ponds, thereby improving our understanding of this pervasive environmental contamination on the Canadian prairies
EVALUATING TRIBUNAL DECISIONS TO RELEASE OR DETAIN THOSE NOT CRIMINALLY RESPONSIBLE ON ACCOUNT OF MENTAL DISORDER
Get PDFCanadians adjudicated Not Criminally Responsible on Account of Mental Disorder (NCR) are detained in forensic psychiatric hospitals under a jurisdictional review board (RB) regulated by the Canadian Criminal Code. Research is limited on whether jurisdictional RB practices uphold the federally legislated balance between public safety and social reintegration. This research investigated whether federal law is applied consistently within the Alberta RB (ARB) system across three phases. Phase One tracked the trajectories and outcomes of NCR individuals through the ARB system, Phase Two determined the predictors of ARB decisions and whether they account for risk or legislatively relevant information, and Phase Three examined forensic risk assessment instruments and their utility to assist forensic decision-making. Instruments included the Level of Service – Case Management Inventory, Historical Clinical Risk Management 20 – Version 3, and the Revised Violence Risk Appraisal Guide. A retrospective archival longitudinal design was used to examine a NCR cohort (n = 109) that entered the ARB system between 2005 and 2010 and their respective hearings (n = 327). Results demonstrated that the ARB aligned their operational and management practices with federal legislation, but unique deviations contributed to novel trajectories and outcomes under RB supervision compared to other provinces. Dispositions varied as a function of risk level and were informed by clinician recommendations. Although risk-relevant information was supplied to the ARB by forensic professionals, key criminogenic risk/need factors as defined by the LS/CMI were absent in most clinical reports. ARB decision-making, however, was still strongly predicted by risk and legislatively relevant information associated with general and violent recidivism. As time under ARB supervision passed and release likelihoods increased, the ARB progressively favoured dynamic over static factors germane to treatment change and risk management. Evidence supported the validity of the study instruments in the appraisal and management of recidivism, especially for violence. Federal duties charged to jurisdictional RBs in the management of NCR populations demands an assiduous consideration of risk and legally relevant information. Forensic risk assessment instruments are reliable and valid aspects of traditional offender programming and the results suggested that they may assist with the appraisal and management of criminal risk anchored in evidence-based practice. Clinical and policy implications of this research for RBs and forensic professionals are discussed
KASKA LEGAL UNDERSTANDINGS OF LAND
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DEVELOPMENT OF AN EFFICIENCY RANKING SYSTEM FOR BEEF COWS AND A COMPARISON OF THE DIGESTIVE PHYSIOLOGY BETWEEN EFFICIENT AND INEFFICIENT COWS
Get PDFBeef cows (n = 100) were used in a 2-yr selection system based on cow rump fat thickness at calving, calving date, and calf weaning weight (% dam BW). The 9 most (ME) and least efficient (LE) cows were used to compare feed intake and ruminal fermentation using four 26-d periods with decreasing dietary nutrient density. There were no phenotype × diet interactions for variables of primary interest. Rump fat and calf weaning weight were greater and calving date was earlier for ME than LE (P ≤ 0.032). The ME cows were lighter (P < 0.001) but had similar DMI (P = 0.93) to LE cows, resulting in greater DMI (%BW; P < 0.001). Ruminal contraction amplitude height and area (P ≤ 0.015), and ruminal digesta weight were greater for LE than ME cows (P = 0.043). Ruminal aNDFom passage was greater for ME cows than LE cows (P = 0.047) but the rate of aNDFom degradation did not differ (P = 0.69). Total tract digestibility did not differ. Efficient cows had greater rump fat, weaned heavier calves, ate more relative to their BW, had smaller ruminal digesta mass, and greater ruminal passage of aNDFom without reducing digestibility
Activation of the Anaphase Promoting Complex as a Possible Treatment Strategy for Hutchinson Gilford Progeria Syndrome
Get PDFNumerous factors promote cellular aging, including the accumulation of protein within the nuclear lamina, leading to disrupted gene expression. An extreme example of this is found in children suffering from the premature aging disease, Hutchinson-Gilford Progeria Syndrome (HGPS). HGPS is a rare disease that affects children, causing premature aging and death around the age of 14. It is caused by a mutation in the LMNA gene, leading to the production and accumulation of the cytotoxic protein progerin. Progerin has downstream impacts on various cellular functions, such as nuclear morphology, heterochromatin organization, mitosis, DNA replication and repair, and gene transcription. Unfortunately, there is currently no cure for HGPS, and existing treatments still require further development to improve the quality of life for affected children. This research proposes a novel avenue of treatment that focuses on reducing progerin levels within cells by examining the potential of the Anaphase Promoting Complex (APC). The APC is a conserved multiprotein complex that promotes cell cycle progression by targeting proteins such as cyclins for ubiquitin and proteasome-dependent destruction. Moreover, the APC is crucial for mounting cellular stress responses and promoting longevity. Based on the evidence indicating that HGPS is characterized by genomic and proteomic instability, impaired metabolic signaling, mitochondrial dysfunction, and low proteasomal activity, which are cellular functions where the APC plays an important role, we hypothesized that an elevated APC activity would impact progerin levels. Using HGPS primary fibroblasts grown in tissue culture, we observed decreased progerin levels in cells treated with Mad2 inhibitor (M2I-1, an APC activator) compared to cells treated with DMSO (vehicle control). We observed that APC activation via M2I-1 induced morphological changes resulting in a higher proportion of cells resembling non-diseased cells. Likewise, APC activation increased the number of doublings of HGPS fibroblasts, which could be an indicator of cellular repair. APC-progerin interactome, assessed by proximity ligation assays (PLA) and co-immunoprecipitation (Co-IP), showed an interaction between APC subunits and progerin. Additionally, we observed that the proteasome inhibitor MG132 decreased progerin levels in HGPS fibroblasts; when MG132 was combined with M2I-1, progerin levels decreased even further. We concluded that autophagy partly mediates progerin removal after the APC is activated. To further explore this hypothesis, we treated HGPS fibroblasts with chloroquine alone or in combination with M2I-1, MG132, or MG132 and M2I-1. Chloroquine, an autophagy inhibitor, partially inhibited the effect of M2I-1, increasing progerin levels and colocalization with ubiquitin. These results are remarkable since to remove proteins in HGPS the APC would be asociated with autophagy. This research has the potential to benefit children suffering from this devastating disease and the increasing senior population, as aging is a major risk factor for cardiovascular diseases, in particular. Therefore, studying the pathways that link progeria with the normal aging process offers insight into developing potential therapeutic strategies for common diseases associated with aging
An Evaluation of Bigmouth Buffalo (Ictiobus cyprinellus) and Common Carp (Cyprinus carpio) Association within the Qu'Appelle River System and its Implications for Species Conservation
Get PDFBigmouth buffalo (Ictiobus cyprinellus) is a fish species at risk in the Qu’Appelle River system of Saskatchewan, Canada. Little is known about their behaviours or how they have been impacted by the introduction of invasive common carp (Cyprinus carpio) into the system. As such, I had several main objectives within my study: 1) to determine the large-scale movements of bigmouth buffalo; 2) to assess whether bigmouth buffalo and common carp associate within Buffalo Pound Lake; 3) to determine which environmental factors (if any) affected the habitat selection of either species; and 4) to report other findings that may be relevant for species management.
I captured and surgically implanted bigmouth buffalo and common carp with acoustic telemetry tags and recorded their movements. I then modeled my findings using R to determine association and the effect of environmental factors on their habitat selection. I found that bigmouth buffalo captured in Buffalo Pound Lake did not move throughout the Qu’Appelle River, and instead preferred to remain within the lake itself. Common carp left the lake during spawning to go upstream to a known spawning site, but bigmouth buffalo did not.
I also discovered that outside of the May spawning period, the two species do not typically associate. Instead of spending more time in the shallows as we would expect, bigmouth buffalo were instead found in more open waters, while carp preferred the warm shallows. Even in the winter when overwintering space is limited, the two species did not associate. Both macrophyte presence and daily maximum noise had negative effects on habitat selection. Daily mean temperature did also have an effect, though this effect changed depending on the region of the lake. As temperature is consistent throughout the lake, it may be an indicator of some behavioural difference or instance of competition between the two species.
Overall, I found that there is a possibility that competitive exclusion may be occurring. However, further research must be done to conclusively determine whether this is the case. Particularly as bigmouth buffalo are not recruiting as much and grow much slower than common carp do, which may lead to local extirpation once the population becomes too old
Ligand Development in the Coordination Chemistry and Selective Extraction of Platinum Group Metals
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