identifier: Karim, Md. Maruf Ul <https://research.library.mun.ca/view/creator_az/Karim=3AMd=2E_Maruf_Ul=3A=3A.html>   (2010) Dynamic modeling of a wind-diesel-hydrogen hybrid power system.  Masters thesis, Memorial University of Newfoundland.

abstract: A dynamic model of Wind-Diesel-Hydrogen based system corresponding to Ramea electrical power system has been developed in this research. The literature starts with reviewing of a number of research papers similar but not same as what is accomplished by this research work. As the parts of that system, wind turbines, diesel generators, electrolyzers, hydrogen tanks and hydrogen generators have been designed in Matlab Simulink and SimPower environments. The system performances along with the sensitivity analyses have been carried out in Homer followed by the designs of constituents. Further analysis and explanations are depicted with all components in integrated form. All the simulation parameters are tabulated and the output results are portrayed in diagrams. Finally the thesis is concluded with brief summery and future scopes.


identifier: Brand, Emma <https://research.library.mun.ca/view/creator_az/Brand=3AEmma=3A=3A.html>   (2010) The virtual source method for imaging steeply dipping structures using a walk-away VSP Acquisition geometry.  Masters thesis, Memorial University of Newfoundland.

type: Thesis NonPeerReviewed

abstract: Seismic interferometry is a recently developed geophysical technique that has been used almost exclusively to solve imaging problems in petroleum environments.  It is a method that has a broad range of applications, however one of the most well-known is the ability of the technique to create virtual sources at the location of buried receivers, without knowledge of the subsurface velocity between the true surface sources and the receivers.  This research focuses on a problem in a minerals environment, in which a shallow, steeply dipping sub-surface feature is to be illuminated using the virtual source method, a form of seismic interferometry.  The research presented here uses both a ray tracing analysis and 2D synthetic seismic modelling to understand the implementation issues associated with the virtual source method.  The ultimate aim is to understand the acquisition and processing requirements to image optimally a shallow, steeply dipping sub-surface feature in a hard rock environment.


identifier: Polomska, Anna Maria <https://research.library.mun.ca/view/creator_az/Polomska=3AAnna_Maria=3A=3A.html>   (2010) Elastic properties of porous silicon superlattices.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The elastic properties of porous silicon single layers and superlattices were determined by means of Brillouin light scattering.  The quality of the Brillouin spectra dependent on the porosity of the porous layer and significant improvement was observed with the increase of porosity.  The morphology and thicknesses of the porous silicon films were studied using scanning electron microscope.  The porosity of both single and multilayered films was calculated using gravimetric method. -- The elastic constants of p-Si superlattices composed of layers of various porosity were compared to values of effective elastic constants obtained from the model proposed by Grimsditch and Nizzoli [M. Grimsditch and F. Nizzoli, Phys. Rev. B, 33, 8, 5891, 1986] which was reported to be applicable for other types of semiconducting superlattices.  As the model requires the elastic constants of the constituent layers of the superlattice as input, the set of elastic constants was determined for each single porous silicon layer assuming cubic symmetry. -- The bulk phonon velocities and respective elastic constants of single layers and superlattices decreased with increasing average porosity of the film.  The effective elastic constants of the superlattices were calculated directly from the spectra collected at smallest incident angle as well as obtained through the fitting of data with expressions for angular dependence of the velocities of the bulk phonons.  The fitting was done with and without constraints on the values of elastic constants (c₁₁ > c₃₃).  The longitudinal and transverse elastic constants of the superlattice (c₃₃ and c₄₄) showed excellent agreement with the model for all the approaches, while the values of c₁₁ and c₁₃ agreed only when the constraints were imposed. -- Based on the results only partial agreement with a model may be concluded.  An excellent agreement for two elastic constants for all superlattices may either mean the other two cannot be determined due to uncertainties involved in the experiments or that the model needs corrections in order to work for superlattices created by electrochemical etching of a crystalline parent wafer.


identifier: Blundon, Phillip <https://research.library.mun.ca/view/creator_az/Blundon=3APhillip=3A=3A.html>   (2011) The geomorphic footprint of ice streaming in the Newfoundland ice cap mapped from remotely sensed data.  Masters thesis, Memorial University of Newfoundland.

abstract: This thesis has no abstract


identifier: Lowe, D. G. (David George) <https://research.library.mun.ca/view/creator_az/Lowe=3AD=2E_G=2E_=28David_George=29=3A=3A.html>   (2009) Provenance and paleodrainage of Late Jurassic and Early Cretaceous reservoir sandstones in the Flemish Pass and Orphan Basins.  Masters thesis, Memorial University of Newfoundland.

abstract: Late Jurassic to Early Cretaceous potential reservoir sandstones from three industry exploratory wells in the Flemish Pass and Orphan Basins were studied for provenance analysis. The sandstones from this study formed during intracratonic rifting that preceded the breakup between North America and its European conjugate margins and seafloor spreading in the North Atlantic. Most were deposited during the Tithonian and Neocomian North Atlantic Rifting stage, during which rifting intensified between Iberia and the Grand Banks and the deposition of important reservoir sandstones occurred regionally. -- Heavy mineral fractions were isolated from cuttings samples from six syn-rift sandstone units. The studied sandstones range in age from Tithonian to Albian. Three heavy mineral approaches were used to determine provenance and make correlations: (1) U-Pb geochronology and petrography of detrital zircons, (2) detrital heavy mineral grain counts and ratios, and (3) geochemistry of detrital tourmalines. -- Based mainly on detrital zircon ages and petrography and detrital tourmaline geochemistry, the predominant first-cycle sediment sources included the Neoproterozoic arc-phase igneous rocks of the Avalon Zone as well as the Ordovician to Devonian magmatic rocks and metasedimentary rocks present in the Central Mobile Belt. There is abundant petrographic and heavy mineral evidence to support significant recycling of material from cover sequences in these tectonic zones as well, likely including Early and Late Paleozoic sedimentary rocks which are ubiquitous in both zones. -- Such a source signature requires uplifted source areas to be present in the west, including parts of the Bonavista Platform, Interior Newfoundland, Northeastern Newfoundland Shelf, and potentially parts of the Irish conjugate margin, including the Porcupine Bank. Thus, paleodrainage orientations and delivery of coarse clastic detritus into the Flemish Pass and Orphan Basins was predominantly from the west during the Late Jurassic to Early Cretaceous, as seafloor spreading began between the Grand Banks and Iberia. Based on this information, one would expect to find reservoir facies sandstone units of this age concentrated along the western margins of the Flemish Pass and Orphan Basins, with deteriorating reservoir grade towards the east. -- A number of the studied sandstones in the Flemish Pass Basin show evidence for partial sourcing from the south, including proximal sources and distal sources as far south as the Avalon Uplift; verifying previous ideas that the Avalon Uplift existed as a significant positive regional tectonic element as incipient seafloor spreading began between Iberia and the Grand Banks. There is no evidence to support sourcing from the east, off of the Iberian margin or the Flemish Cap-Galicia Bank continental fragment, and material from these areas is instead interpreted to have been shed into the incipient Atlantic Ocean or Bay of Biscay. -- Mesozoic aged detrital zircons were present in two samples, and proved useful for constraining the depositional age of these sandstones. The most likely known sources of these grains include the Budgell Harbour Stock, in Central Newfoundland, or an Early Cretaceous granite basement intercepted by the Bonavista C-99 well in the West Orphan Basin. Both of these potential sources are located to the west of the studied units.


identifier: Browne, Greg <https://research.library.mun.ca/view/creator_az/Browne=3AGreg=3A=3A.html>   (2011) A driven approach to proper vehicle modeling and model validation.  Masters thesis, Memorial University of Newfoundland.

abstract: As the use of model-based design in the automotive industry accelerates, so must the efficiency of modeling techniques and the thoroughness of model validation. -- The research presented constructs an energy-based (bond graph) proper vehicle model.  This model includes all significant system dynamics generated from pressing on the gas pedal to the resulting vehicle translation. -- The Model Order Reduction Algorithm provides a mechanism to quantitatively rank each element in the model and determine its contribution.  The complete model, containing 65 elements, is reduced to 22 elements, provides simulation results of adequate agreement, and still contains over 98% of the original system energy.  This proper model reduces the number of calculations by 86% and the simulation time by 92%. -- By using GPS and OBD-II technologies, the model is exercised by logging on-road real-world vehicle data.  By comparing the logged data to the predictions of the model, it is shown that R² > 0.9 can be achieved across different vehicles (compact sedan versus sport utility vehicle) and geographical routes.


identifier: Arifujjaman, Md <https://research.library.mun.ca/view/creator_az/Arifujjaman=3AMd=3A=3A.html>   (2010) Performance and reliability comparison of grid connected small wind turbine systems.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Small wind energy conversion systems are electromechanical devices that generate electricity from wind power for use in commercial as well as residential applications.  System level comparison pertaining to such conversion systems is an important and challenging problem and in-depth analysis is essential for high penetration of wind power.  A set of unique problems associated with this technology requires that the maximum power point tracking control be achieved through a simple, efficient, and most importantly, highly reliable manner.  This research identifies these challenges and subsequently presents a comparison in terms of the performance and reliability of a furling control grid connected Permanent Magnet Generator (PMG) and Wound Rotor Induction Generator (WRIG)-based small wind turbine system.  The power conditioning system for grid connection of the PMG-based system requires a rectifier, boost converter and a grid-tie inverter, while the WRIG-based system employs a rectifier, a switch and an external resistance in the rotor side with the stator directly connected to the grid.  The proposed research develops the system level mathematical model for the power conditioning system losses that fluctuates with the wind speed.  It is found by the simulation that compared to the PMG-based system, the WRIG-based system can provide low power losses at low wind speeds, thus resolving the typical obstacle of variable speed operation.  The comparison is further enhanced by investigating the annual energy capture, annual energy loss and efficiency for the wind speed information of eight test sites in Newfoundland and Labrador, Canada: Battle Harbour (BH); Cartwright (CW); Little Bay Island (LB); Mary's Harbour (MH); Nain (NA), Ramea (RA); St. Brendan's (SB); and St. John's (SJ).  It is demonstrated that the WRIG-based system yields lower energy loss which results in a system of higher efficiency for a wind speed of 2 m/s (cut-in) to 17 m/s (cut-out).  Furthermore, experimental test benches are developed for both systems based on a wind turbine emulator that incorporates furling control and associated dynamics, as well as power conditioning systems required for variable speed operation.  The maximum power extraction to the grid for both systems is ensured by tracking the optimum tip speed ratio.  The experimental energy production is calculated for the regions considered during simulation.  It is found that the WRIG-based system provides 2% more efficiency than the PMG-based system and corresponds well with the simulated conclusion. -- Additionally, the reliability of the power conditioning system for the systems is analyzed at a predetermined wind speed.  The analysis reveals that the Mean Time Between Failures (MTBF) of the power conditioning system of the WRIG-based system is much longer than the MTBF of the power conditioning system of the PMG-based system.  The investigation is extended to identify the least reliable component within the power conditioning system for both systems.  It is shown that the inverter has the dominant effect on the system reliability for the PMG-based system, while the rectifier is the least reliable component for the WRIG-based system.  This research finally concludes that the WRIG-based small wind turbine system with a simple power conditioning system is a much better option for a small wind energy conversion system.


identifier: Agboma, Clement O. (Clement Omojate) <https://research.library.mun.ca/view/creator_az/Agboma=3AClement_O=2E_=28Clement_Omojate=29=3A=3A.html>   (2010) Subsurface moisture storage patterns derived from hydrologic model and satellite measurements during extreme period of dryness.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Spatially distributed subsurface soil moisture dataset with suitable temporal scale are needed for a better understanding of the mechanisms responsible for the recurrent drought outbreaks over the Canadian Prairie. However, there are no soil moisture data at depths exceeding a few centimeters over the Canadian Prairie sub-catchments thereby placing enormous constraints on the feasibility of studies that require such information. Hence, this thesis explores the use of a physically based, spatially distributed hydrologic model in reproducing the patterns of the spatial and temporal distribution of soil moisture over the drought-prone 13,000 km² Upper Assiniboine River Basin (UARB) in the Canadian Prairie. Prior to making any inferences on the spatial and temporal dynamics of the simulated subsurface soil moisture over this large domain, a necessary requirement was to validate the model's simulated output of other hydrologic variables. These validations were accomplished using observed measurements of streamflow, snow depth, moisture storage change from geological weighing lysimeters and estimates of the total water storage from the Gravity Recovery And Climate Experiment (GRACE) remote sensing satellite system. After an assessment of the simulated outputs from the Variable Infiltration Capacity (VIC) model, which were found to be of acceptable quality, this thesis thereafter focused on assessing the spatial distribution of the subsurface soil moisture over the large catchment. Therefore, in the first case study undertaken in this thesis, it was demonstrated that with a structurally sound model (one equipped with adequate land surface parameterization) such as the VIC model, it is possible to generate soil moisture datasets at different spatial and temporal scales for use in areas such as the Canadian Prairie and other geologically complex terrains where observed soil moisture measurements are lacking. -- Furthermore, retrieval of the terrestrial moisture storage dataset from the Gravity Recovery And Climate Experiment (GRACE) satellite remote sensing system is possible when the catchment of interest is of large spatial scale. These dataset are of paramount importance for the estimation of the total storage deficit index (TSDI), which enables the characterization of a particular drought event from the perspective of the terrestrial moisture storage over that catchment. Incidentally, the GRACE gravity signal over the 13000 km² Upper Assiniboine River Basin on the drought-prone Canadian Prairie is so poor therefore making the computation of the total storage deficit index for this basin infeasible. Consequently, the estimation of the terrestrial moisture storage from other reliable sources becomes imperative in order to enable the computation of the TSDI over this basin. -- In the second case study undertaken in this thesis, simulation of the total moisture storage over the Upper Assiniboine River Basin was accomplished utilizing the spatially-distributed land surface model, VIC, which was then employed in the estimation of the TSDI over this basin for subsequent characterization of the recent Prairie-wide drought. Interestingly, the resulting temporal patterns in the computed TSDI from the land surface model reveal a strong resemblance with the same drought characterization undertaken over the larger adjacent Saskatchewan River Basin, which was accomplished utilizing terrestrial moisture storage from the GRACE-based approach. In this second case study, it has been shown that in the computation of the total storage deficit index over small-scale catchments during anomalous climatic conditions that propagate extreme dryness through the terrestrial hydrologic systems, simulations of the total water storage from a structurally sound model such as the VIC model could be resourceful for the computation of the monthly total storage deficit index if no constraint is placed on the availability of accurate meteorological forcing. -- Finally, understanding the memory in land surface processes, such as that in the subsurface moisture storage has great implication for seasonal weather prediction over a catchment. However, given that there are no physical observations of soil moisture at depths of hydrological importance or measurements of the total water storage, it is infeasible to undertake studies on land-atmosphere interactions. In the last case study undertaken in this thesis, effort is focused on estimating the memory in the simulated deep soil moisture and total water storages over the 406,000 km² Saskatchewan River Basin (SRB) in the Canadian Prairies. Finally, given the similarity in the simulated deep moisture storage anomaly and the model-based TSDI, it was inferred that the former could serve as a descriptor of drought over this large Prairie sub-catchment.


identifier: Zhai, Zhichun <https://research.library.mun.ca/view/creator_az/Zhai=3AZhichun=3A=3A.html>   (2009) Some regularity estimates for mild solutions to fractional heat-type and Navier-Stokes equations.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Please see thesis for abstract.


identifier: Both, Adrianus <https://research.library.mun.ca/view/creator_az/Both=3AAdrianus=3A=3A.html>   (2010) Assessing the performance of the blue mussel (mytilus edulis) in an integrated multi-trophic aquaculture (IMTA) setting.  Masters thesis, Memorial University of Newfoundland.

abstract: Integrated multi-trophic aquaculture (IMTA) uses extractive organisms such as mussels to reduce wastes of fed organisms such as finfish and provide additional product for the growers. The physical and biochemical properties of Atlantic cod (Gadus morhua) wastes (feces and uneaten feed) were analyzed and the waste remediation potential and performance (growth and biochemical composition) of blue mussels (Mytilus edulis), were assessed. Waste generated daily by Atlantic cod represented 24.9% of the feed added to the system. Effluent was composed of particles <70 µm (36%), 70-500 µm (31%) and particles >500 µm (33%). Particles <70 µm had significantly less organic matter, lipids and fatty acids and were expected to be ingested more frequently by mussels. Effluent contained the fatty acid zooplankton markers (22: 1ω11 and 20: 1ω9) which accumulated in mussels. Effluent fed mussels had an inferior performance and contained significantly more MUFA, 18: 1ω9 and the NMID 20:2a as well as less ω3 than algae fed mussels. It is believed aquaculture wastes have potential as a diet supplement when natural seston is low.


identifier: Goetting, Kathryn <https://research.library.mun.ca/view/creator_az/Goetting=3AKathryn=3A=3A.html>   (2010) Is the Newfoundland redfish fishery sustainable? : modelling recovery strategies for two redfish stocks.  Masters thesis, Memorial University of Newfoundland.

abstract: Marine resources have supported the economy and culture of Newfoundland and Labrador (NL) for over 500 years.  Stock abundance has fluctuated in most species due to increased pressure to fulfill new markets, the development of new gear, and survive in a competitive industry.  In some cases, declines in resource abundance led to closures or moratoriums.  The redfish (Sebastes species) fishery in NL has stocks that have remained opened but have experienced declines in total allowable catch (TAC), while others have been closed in hopes of recovery. -- This thesis models the recovery strategies of two Newfoundland redfish stocks, Unit 1 (Gulf of St. Lawrence) and Unit 2 (Laurentian Channel), using the Schaefer model.  This analysis examines the potential for these stocks to reach biologically sustainable biomass levels under different harvesting levels.  Due to the slow growing nature of the Sebastes species, recovery is slower than in other groundfish species.  Despite this obstacle, and other opposing factors, neither stock examined for this research has reached a critical point from which recovery is impossible.  However, conservation and precaution are key components for the future of this fishery in this region.


identifier: Robinson, Julie L. (Julie Lee) <https://research.library.mun.ca/view/creator_az/Robinson=3AJulie_L=2E_=28Julie_Lee=29=3A=3A.html>   (2010) Conservation of the endangered limestone endemic Salix jejuna : effects of anthropogenic disturbance on habitat and life history.  Masters thesis, Memorial University of Newfoundland.

abstract: Anthropogenic disturbance has been shown to have negative impacts on the recovery of endangered or rare species. Specific recovery objectives for Salix jejuna, an endangered prostrate shrub endemic to the globally rare limestone barrens habitat of Newfoundland (Canada), include assessing the population dynamics of natural populations, understanding limiting factors, defining threats and mitigating controllable threats where possible. As a large portion of S. jejuna's habitat has been anthropogenically-disturbed, understanding the effects of disturbance on species persistence are central to promoting species recovery. -- An assessment of habitat features revealed that anthropogenically-disturbed substrates were more homogeneous than undisturbed, natural substrates, with more gravel, less exposed bedrock, decreased soil moisture, and increased nutrient content. Populations resident on anthropogenically-disturbed habitats tended towards a more "annual" dynamic, with a greater proportion of seedlings, lower levels of clonal growth, and a younger median age compared with populations on naturally-disturbed substrates. Therefore, specific recovery plans for S. jejuna should include the elimination of continual disturbances such as off-road vehicle use and the active restoration of disturbed habitat to restore natural ecosystem processes, to reflect adjacent undisturbed natural habitat, and to promote the clonal reproductive traits of natural populations.


identifier: Collins, Kayla D. <https://research.library.mun.ca/view/creator_az/Collins=3AKayla_D=2E=3A=3A.html>   (2010) Evaluating the impact of enhancing information and communication technology in a rural, community-model primary health care setting in Newfoundland and Labrador.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The Connaigre Peninsula primary health care (PHC) setting was chosen by the Newfoundland and Labrador government to explore the value of sharing client information in an interdisciplinary environment, by building on existing technologies to fill gaps in information and communication capabilities. A series of technical enhancements were implemented in this setting over approximately one year. The purpose of this study was to evaluate the impact of these technical enhancements. Key stakeholders were engaged in the development of an evaluation framework and later evaluation protocol that was used to guide the evaluation. -- Using a comparative case study design, two additional PHC sites with varying levels of technical capacity were included as comparison sites in the evaluation: Bonne Bay, which had minimal technical capacity, and Twillingate/New World Island, which had a high level of technical capacity. -- Primary data collection included a survey and focus group with PHC team members and interviews with key stakeholders. Secondary data collection included use of data collected at the same sites as part of another study (Team Effectiveness/Scope of Practice Survey and Client Satisfaction Survey) and a review of existing documents. -- Findings indicate that the enhancement of information and communication technology (ICT) can facilitate various aspects of PHC delivery including team functioning, quality of care and administrative functioning. Findings and lessons learned can be used to support the enhancement of ICT in other community-model PHC settings, as well as facilitate the advancement of a province-wide electronic health record (EHR).


identifier: Alam, Md. Shah <https://research.library.mun.ca/view/creator_az/Alam=3AMd=2E_Shah=3A=3A.html>   (2010) Influence of different parameters on shear strength of FRP reinforced concrete beams without web reinforcement.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: This research focuses on the shear behaviour of FRP reinforced concrete members without web reinforcement. The investigation was carried out in three phases, viz., experimental, analytical, and numerical simulation. The experimental investigation was carried out to investigate the effect of different parameters on the behaviour and concrete contribution to the shear strength. A new test set-up was designed and constructed for testing the beams. A total of thirty-six beams reinforced with GFRP, CFRP, and steel bars were tested. The test parameters were shear span-to-depth ratio (a/d), depth of beam (d), longitudinal reinforcement ratio (p), concrete compressive strength (f'c), and reinforcement type. Each of the parameters was varied while keeping all other parameters constant. The structural behaviour of the tested beams with regard to the deflections, strains, modes of failure, and ultimate capacity was examined. The test results revealed that there is an effect of the parameters on the shear strength of the beams. -- The experimental results were compared to the predictions of some of the available design codes, manuals, and guidelines for calculating the concrete contribution to the shear strength. It was observed that the predicted results did not match well with some of the experimental results. The experimental investigation revealed that there is a relationship between the cracking load and the shear strength of the beams. This relationship was further verified using the test results of 101 FRP reinforced beams that were available in the literature. Based on this relationship, a simple yet robust shear design method was proposed to calculate the concrete contribution to the shear strength of FRP reinforced rectangular beams without transverse reinforcement. The proposed method was validated against the experimental results of the current investigation as well the test results obtained from the literature. The predicted results using the proposed method were compared with the predicted results of some of the available design codes, manuals, and guidelines. The proposed method was found to be more consistent and reliable in predicting the shear strength of FRP reinforced concrete members than the other methods. The method is simple to apply and is suitable for use in design codes. -- Finally, finite element analysis was carried out to simulate the behaviour of shear critical FRP reinforced concrete beams with a wide range of design parameters such as shear span-to-depth ratio, depth of beam, reinforcement ratio, concrete strength, and reinforcement type. For this purpose, two concrete material models were used. The models were a concrete damage plasticity model (Model-1) and a hypoelastic concrete model (Model-2). An idealized tension-stiffening model was proposed based on the reinforcement type and varies as a function of the member strain. The models were implemented in general purpose finite element programs ABAQUS and ADINA, respectively. The models were used to simulate the experimental results of some of the beams tested in this investigation and to examine how well these models simulate the behaviour of shear critical FRP reinforced concrete members. The models predicted results are in a reasonable agreement with the experimental results. It was observed that a better prediction can be achieved using a proper tension-stiffening idealization.


identifier: Wang, Li <https://research.library.mun.ca/view/creator_az/Wang=3ALi=3A=3A.html>   (2009) Photoinduced electron and energy dynamics in architecturally designed molecular assemblies containing C₆₀-fullerene.  PhD thesis, Memorial University of Newfoundland.

abstract: The studies presented in this thesis describes the excited state dynamics of electron and energy transfer in one- and two-dimensional π-conjugated molecular constructs with fullerenes as electron accepting chromophores.  -- This thesis first starts with the energetics and dynamical processes in the excited state of π-conjugated OPV/OPE oligomers following photon capture. Systematic analysis and characterization of the excited states formed after excitation includes the detailed quantitative understanding of the structural, electronic and vibronic parameters of π-conjugated OPV/OPE oligomers, as well as the substituent and orientation effects that dictate radiative, non-radiative relaxation pathways and the reaction dynamics of these transient excited states. -- With the detailed understanding of the excited state properties of π-conjugated OPV/OPE bridges, the photo-induced electron and energy transfer in the π-bridged C₆₀ systems [A-(π-B)C/L-A] was undertaken. A major portion of the research centered on diphenylamino derivatized molecular assemblies. The excited states of molecular assemblies containing phenylamino moieties are known to be complex and many facets of dynamics are still controversial. Systematic investigations of the donor substituent effect on the excited state dynamics and the photo-induced electron and energy transfer in the donor substituted (π-B)-bridged C₆₀ systems (A-[π-(D)BC]n-A) were scrutinized. Ultimately, this research should teach us how to engineer molecules in the potential opto-photonic device applications, i.e. photosynthetic devices that convert photonic energy into chemical energy. -- With the increased understanding of the ground and excited state properties of π-conjugated OPV/OPE oligomers with donor substituents, the last chapter is to assess the performance of two-dimensional H-shaped OPV/OPE chromophores with electron donor and acceptors as potential sensors for specific analytes.


identifier: Gosse, Paul W. <https://research.library.mun.ca/view/creator_az/Gosse=3APaul_W=2E=3A=3A.html>   (1998) Future mathematics in a TI-83 graphing calculator environment.  Masters thesis, Memorial University of Newfoundland.

abstract: Reformed mathematics curricula are demanding increased use of graphing calculator technology.  This report describes the background, need for, and evolution of a set of activities supporting implementation of graphing calculator technology in high school. Associated with the manual is a five-day professional development institute project. The manual is a self-contained body of notes and linked exercises describing TI-83 application throughout secondary school mathematics. It assumes no prior TI-83 knowledge. It is designed to accommodate personal instruction. Full solutions and extensive explanations are provided. A facilitator package including a complete description of managing such an institute is appended. It includes a glossary of terms and is fully referenced. Teaching tips, which provide alternate strategies and enhancements, are also included.


identifier: Hu, Rui <https://research.library.mun.ca/view/creator_az/Hu=3ARui=3A=3A.html>   (2009) Stability and bifurcation analysis of reaction-diffusion systems with delays.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The work focuses on the stability of steady state and local bifurcation analysis in partial differential equations with different delays. Especially, a neural network model with discrete delay and diffusion is proposed in the first part; a diffusive competition model with uniformly distributed delay is studied in part 2. An extended reaction-diffusion system with general distributed delay is treated in part 3. In the last part, a Nicholson's blowflies model with nonlocal delay and diffusion is discussed. -- For a diffusive neural network model with discrete delay, by analyzing the distributions of the eigenvalues of the system and applying the center manifold theory and normal form computation, we show that, regarding the connection coefficients as the perturbation parameter, the system, with different boundary conditions, undergoes some bifurcations including transcritical bifurcation, Hopf bifurcation and Hopf-zerobifurcation. The normal forms are given to determine the stabilities of the bifurcated solutions. -- In some cases, the model with distributed delay is more accurate than that with discrete delay. We study a competition diffusion system with uniformly distributed delay. The complete analysis of the characteristic equation is given. And via the analysis, the stability of the constructed positive spatially non-homogeneous steady state solution is obtained. Moreover, the occurrence of Hopf bifurcation near the steady state solution is proved by using the implicit function theorem with time delay as the bifurcation parameter. Finally, the formula determining the stability of the periodic solutions is given. -- The uniformly distributed kernel is only one of the widely used time kernel. It is natural to discuss more general time kernels. We consider a class of reaction-diffusion system with general kernel functions. The stability of the constructed positive spatially non-homogeneous steady state solution is obtained under general kernels by using the similar method in part 2. Moreover, taking minimal time delay as the bifurcation parameter, we can not only show the existence of Hopf bifurcations near the steady state solution, but also prove that the Hopf bifurcation is forward and the bifurcated periodic solutions are stable under certain condition. The general results are applied to competitive and cooperative systems with weak kernel function. -- In many application models, if individuals move, it is more reasonable to model delay and diffusion simultaneously, which induces nonlocal delay by employing Britton's random walk method. We study the stability of the uniform steady states and Hopf bifurcation of diffusive Nicholson's blowflies equation with nonlocal delay. By using the upper- and lower- solutions method, we have obtained the global stability conditions at the constant steady states, and discussed the local stability. Moreover, for a special kernel, we have proved the occurrence of Hopf bifurcation near the steady state solution and given formula in determining stability of bifurcated periodic solutions.


identifier: Ellaboudy, Hany <https://research.library.mun.ca/view/creator_az/Ellaboudy=3AHany=3A=3A.html>   (2008) Novel biodegradable and biocompatible elastomers for endostatin delivery.  Masters thesis, Memorial University of Newfoundland.

abstract: Long term, localized continuous release of Endostatin (END) in the vicinity of tumour bed represents a new strategy for neoplastic treatment. The main reason of localization is to maximize the therapeutic outcome and at the same time to reduce the toxic effects on the surrounding tissues due to the exposure to the angiogenesis inhibitory effect of END. The main objective of this study was to design and formulate a biodegradable and biocompatible polymeric device for delivering END at a sustained and constant rate, and at a concentration within its therapeutic window by utilizing the osmotic release mechanism. The new device was prepared by mixing of END with osmotically active excipients and incorporate the mixture as solid particles within a rubbery polyermic matrix. The results demonstrated that this new device achieved a constant and sustained release rate for END for a certain period.


identifier: Khan, Mohammad Jahangir Alam <https://research.library.mun.ca/view/creator_az/Khan=3AMohammad_Jahangir_Alam=3A=3A.html>   (2010) Adaptive power tracking control of hydrokinetic energy conversion systems.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Hydrokinetic energy conversion systems (HECS) are electromechanical devices that operate in free-stream water channels in a manner similar to wind turbines. The fundamental process of fluid-mechanic energy conversion using a hydrokinetic turbine is manifested through a nonlinear performance characteristics. The problem of maximum power tracking evolves around this nonlinearity and the underlying control objective is to regulate the turbine's operating conditions such that system efficiency is in the neighborhood of the optimum point. Through this research, it has been identified that a power tracking method that is independent of the turbine's characteristics, which can be implemented without using underwater/mechanical sensors would be of significant interest to the emerging hydrokinetic energy technologies. Further to a comparative analysis of various traditional wind turbine control techniques, an adaptive tracking approach termed as 'extremum seeking control' (ESC) approach has been adopted. Detailed mathematical formulations pertaining to this novel control solution has been provided and relevant parameter tuning and implementation procedures are presented. -- In order to provide sufficient insight into the design, operation, and control aspects of a real-life hydrokinetic system, a small-scale vertical axis turbine has been developed in this work. This turbine employs a multi-pole permanent magnet alternator for electromechanical energy conversion. A ac-dc-ac power electronic stage interfaces the asynchronous output of the generator to the utility grid through a single-phase connection. Even though a stand-alone test setup is possible, the grid-tied option has been pursued for ease of implementation as well as to explore broader areas of deployment. In addition to modeling and validating all the subsystems in the laboratory, the turbine rotor system has been tested under controlled environment in a tow tank. Associated numerical models have been validated extensively prior to their use in the power tracking control study. In addition, simulation schemes for hydrological flow fields and rotor fluid-dynamic characteristics have been developed as aiding tools to this research. -- The extremum seeking controller parameter tuning and implementation method developed in this work, has been found to be capable of successfully regulating the system operating condition at the optimum point. This method requires minimal information on the hydrokinetic device's operational characteristics and can be potentially deployed in wide range of devices. Further work within this research track includes, implementation of the ESC method in mid to large-sized hydrokinetic systems and development of multi-objective control solutions. As a continuation of this research, active efforts are currently being made such that the true potential of the extremum seeking control and other advanced power tracking techniques can be realized in near-future.


identifier: Tao, Yi <https://research.library.mun.ca/view/creator_az/Tao=3AYi=3A=3A.html>   (2010) Generalized quasilikelihood method for misclassified longitudinal binary data.  Masters thesis, Memorial University of Newfoundland.

abstract: In this practicum we develop the generalized quasi-likelihood approach to analyzing longitudinal binary data with misclassification in response.  We utilize the method of Monahan and Stefanski (1992) to approximate the expectation of an unknown function involved in the calculation of the means and covariances, which are further used to develop GQL estimating functions.  The results of an intensive simulation study show that the proposed method works very well in all the preselected settings.  The efficiency gain as compared to the naive method is remarkable.  The method is robust in the sense that the performance varies just slightly when model parameters change in the simulation. -- Keywords: Logit link; longitudinal binary response; GQL; Misclassification.


identifier: Valley, Peter M. (Peter Martin) <https://research.library.mun.ca/view/creator_az/Valley=3APeter_M=2E_=28Peter_Martin=29=3A=3A.html>   (2010) Fluid alteration and magnetite-apatite mineralization of the Lyon Mountain granite : Adirondack Mountains, New York State.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The Lyon Mountain granite (LMG) is exposed in the Adirondack Mountains of northern New York State and is the host to numerous magnetite-apatite (Kiruna type) deposits. The results in this study suggest that the LMG was emplaced in the middle to late Ottawan orogeny between 1065 and 1045 Ma, along extensional shear zones during the onset of orogenic collapse. The original protolith, perthitic granite, has been extensively altered by subsequent Na- and K-rich fluids. Early-formed, zircon-poor clinopyroxene-magnetite-apatite deposits related to granite emplacement were remobilized and chemically modified by Na- and F-bearing fluids to form new deposits that crystallized hydrothermal zircon. Age determinations using U-Th-Pb geochronology of these hydrothermal zircon indicate that Na alteration and second generation mineralization occurred between 1040 Ma and 1000 Ma, 20 to 60 million years after crystallization of the host granite. Hafnium isotopes in zircon suggest that Lu-rich apatite and clinopyroxene associated with early-formed ore deposits broke down during Na and F alteration releasing radiogenic Hf from apatite and Zr from clinopyroxene. Granitic dikes and pegmatites which crosscut the fabric of the LMG, are dated between 1040 Ma and 1015 Ma and are contemporaneous with zircon growth in the iron ore deposits. This implies that Na alteration and Fe-mineralization were the result of externally derived fluids that penetrated the Lyon Mountain granite along extensional shear zones during orogenic collapse or by fluids related to granitic dike and pegmatite emplacement. -- The presence of U-Th-Pb zircon ages that are 20 to 60 m.y. younger than the host granites of the magnetite ores, and the highly variable mineralogy of the ore deposits, suggests that multiple fluid and mineralization processes were responsible for ore formation and periodic modification of preexisting ores. However, the presence of magnetite-apatite ore deposits almost exclusively within the LMG implies a "fertility" requirement of the host granite and hence that mineralization was in part related to magmatism.


identifier: Hutchings, Corey Allan <https://research.library.mun.ca/view/creator_az/Hutchings=3ACorey_Allan=3A=3A.html>   (2011) Complexity and continuity: Labrador archaic occupations at Nulliak Cove, Labrador.  Masters thesis, Memorial University of Newfoundland.

abstract: The Labrador Archaic site of Nulliak Cove 1 contains the highest number of reported longhouse structures yet recorded. Since its discovery in 1968, this site has played an important role in the interpretation of Labrador Archaic culture history, despite the limited attention paid to the site as a whole. This thesis attempts to address some of the problems associated with this limited understanding of Nulliak as a large scale site. -- This investigation of Nulliak Cove suggests that there are recognizable continuities in Labrador Archaic cultural traditions over the millennia. This runs counter to our current interpretation of the Labrador Archaic as a population who underwent marked and rapid culture change at various points in their history. Understanding this continuity within Labrador Archaic culture allowed for a reinterpretation of Nulliak Cove that suggests a long period of occupation at the site but also recognizes that change did occur due to both external and internal forces.


identifier: Yu, Yuanlong <https://research.library.mun.ca/view/creator_az/Yu=3AYuanlong=3A=3A.html>   (2010) Cognitive visual perception mechanism for robots using object-based visual attention.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Based on the psychological and physiological fact that humans employ a visual attention mechanism to connect perception and action by selecting the relevant parts of the environment in an unconscious or conscious way and using the relevant parts to produce an appropriate action, this thesis presents a cognitive visual perception paradigm that determines how visual inputs reach awareness and guide actions. -- Based on the idea that a general way of organizing the visual scene is to parcel it into discrete objects, object-based visual attention theory is employed in the proposed paradigm.  This proposed paradigm models robotic visual perception as a three-stage process:  pre-attentive processing, attentional selection and post-attentive perception.  It indicates that robotic visual perception starts from a low-level cognitive attentional selection procedure that guides attention to the relevant object of the scene, followed by a high-level post-attentive analysis procedure that analyzes the attended object and formulates it into an internal mental representation used for further cognitive behaviors. -- The pre-attentive processing stage extracts pre-attentive features and divides the input scene into uniform proto-objects by using an irregular pyramid based segmentation method.  The attentional selection stage guides attention to one proto-object of interest by means of unconscious bottom-up competition and conscious top-down biasing.  The bottom-up competition is modeled by estimating the saliency of each proto-object.  The top-down biasing is modeled by using integrated competition hypothesis:  by directing attention to a task-relevant feature of an object, a competitive advantage over the whole object is produced.  Furthermore, this thesis asserts that the task-relevant feature can be autonomously deduced from the internal representation of the task-relevant object that is specified by or inferred from the current task. -- Once a proto-object is selected by attention, it proceeds to the post-attentive perception stage, which includes perceptual completion processing, extraction of post-attentive features, object recognition, and development of the internal representation of the attended object in long-term memory.  The internal representation is autonomously organized and learned under the framework of probabilistic neural networks in the sense that an object is modeled as a hierarchical cluster.  Thus, each instance in the cluster can be abstracted as a mental state that can be used for high-level cognitive behaviors, such as attentional prediction and action determination. -- This proposed cognitive visual perception paradigm is applied into distinct robotic tasks, including detection of salient objects, detection of task-relevant objects and target tracking.  Experimental results under different conditions are shown to validate this paradigm.


identifier: Cuff, Andrew <https://research.library.mun.ca/view/creator_az/Cuff=3AAndrew=3A=3A.html>   (2011) Dual-frequency acoustic seabed classification on the Scotian shelf, Canada.  Masters thesis, Memorial University of Newfoundland.

abstract: Acoustic seabed classification is typically done using single acoustic frequencies, although it is known that different frequencies can potentially provide additional information on the seabed.  This thesis explores the potential of using two acoustic frequencies, 38 kHz and 120 kHz, from a single beam echo sounder for acoustic seabed classification on the Scotian Shelf, Canada.  The main goals were to assess the characteristics of near-nadir acoustic backscatter as a function of seabed substrate properties and acoustic frequency, analyze differences in frequency response at different spatial scales, and to compare single frequency and dual-frequency classifications of seabed substrate types.  Univariate and multivariate statistical methods were used to determine the statistical characteristics of single and dual-frequency near-nadir acoustic backscatter and to identify frequency differences.  Both supervised and unsupervised classification techniques were used to classify the data.  Results revealed trends in dual-frequency near-nadir backscatter such as higher frequencies and larger sediments generally produce higher backscatter and more heterogeneous and rough seabeds produce variable backscatter.  It was found that differences in frequency responses of backscatter occurred at scales of hundreds of meters.  Finally, it was concluded that dual-frequency classification improved upon single frequency classification at near-nadir incidence angles.


identifier: Wu, Shuang <https://research.library.mun.ca/view/creator_az/Wu=3AShuang=3A=3A.html>   (2011) Dataflow synthesis and verification for parallel object-oriented programming languages.  Masters thesis, Memorial University of Newfoundland.

abstract: The HARPO project aims to develop a methodology to generate and verify hardware configurations from a high level object-oriented programming language.  Specifically, the compiler of a high-level object-oriented programming language, HARPO/L (standing for HARdware Parallel Objects Language), outputs hardware configurations that are mappable to a coarse-grained reconfigurable architecture (CGRA) system. -- This thesis develops a data flow synthesis method, which is a critical component in the middle-module of the HARPO/L compiler.  This method is extendable to most other high-level parallel object-oriented programming languages. -- In addition, this thesis proposes an automatic verification system for HARPO/L.  An algorithm to compute weakest liberal precondition of parallel compositions, which fills the gap between verification of programming languages with parallel compositions and state-of-art automatic verification approaches, is introduced.  This algorithm also helps verifying the absence of data race and the absence of deadlock, and has good interplay with grainless semantics.


identifier: Denommee, Kathryn C. (Kathryn Christine) <https://research.library.mun.ca/view/creator_az/Denommee=3AKathryn_C=2E_=28Kathryn_Christine=29=3A=3A.html>   (2011) A high-resolution reconstruction of paleo-hurricane strikes from the Blue Hole, Belize.  Masters thesis, Memorial University of Newfoundland.

abstract: Annually laminated sediments are one of the most valuable sources of paleo-climatic proxy records. Sediment cores collected from the Blue Hole of Lighthouse Reef, Belize provide a continuous, high-resolution proxy record for hurricane strikes spanning the past ca. 1200 years. This record is based on the identification of anomalous graded beds, interpreted as event layers that are deposited as overwash material under the influence of tropical storms and hurricanes. These beds are found interbedded with normal background sediments that consist of annually laminated biogenic carbonate muds that, in combination with ¹⁴C AMS dating, allow for the development of an absolute storm chronology. In order to facilitate the recognition and counting of these not always well-developed laminations, a new quantitative method was developed for use with the widely-used Geoscan line scanning camera system. The hurricane signal at the Blue Hole was found to exhibit multi-centennial frequency variability, with periods of increased activity occurring between ∼1100 and 600 yBP and ∼100 yBP to present, and a period of decreased activity occurring between ∼600 and 100 yBP. These frequency shifts correspond other North Atlantic Basin paleoclimatic features, in particular sea surface temperature variations observed during the Medieval Warm Period and the Little Ice Age and known migration patterns of the Inter-tropical Convergence Zone.


identifier: El-Dali, Abdelmeneim <https://research.library.mun.ca/view/creator_az/El-Dali=3AAbdelmeneim=3A=3A.html>   (2011) Charge transfer dynamics in bridged donor-acceptor molecular assemblies.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The metabolic processes inherent to life on earth are driven by chemical transformations that are too numerous to count. Important classes of reactions involve the transfer of charge, i.e. electron transfer and proton transfer as well as group transfer reactions. The recent X-ray crystal structure revealed that proton coupled electron transfer reactivity plays crucial rule in the photosynthetic apparatus. The theory to describe proton coupled electron transfer is not as evolved to that which described electron transfer. There exist a number of unresolved issues. The primary goal of this work was to understand at a very fundamental level, the molecular properties that dictate chemical reactivity so as to quantify the important factors which influence the charge transfer excited-state dynamics. In this work, we have applied a variety of different techniques to study the properties and the mechanism of ground state and excited state intermolecular and intramolecular proton transfer and charge transfer in chromosphere assemblies. -- The bbim system was studied to outline fundamental investigation with respect to the excited state intramolecular proton transfer. The ground state potential energy surface was characterized by temperature dependent ¹H NMR to establish the energetics of the enol / keto inter-conversion in the ground state. Analysis of the temperature dependent ¹H NMR yielded ΔHǂ = 27 kJmol⁻¹, ΔSǂ = -133 JK⁻¹mol⁻¹. Upon excitation, bbim is a dual emitter with high energy emission band at 427 nm and 550 nm respectively. The intensity of transitions was found to be solvent dependent. Addition of D₂O resulted in dramatic changes in the intensity and energetics of emission spectrum envelope. The emission spectra were subjected to a Franck-Condon line shape analysis and provide structural and electronic of the excited states. -- The photophysical properties of bbim were dependent on the electrolyte. Dramatic changes in the absorption and emission spectra were observed with [NBu₄]F and [NBu₄]OH. Titration experiment with a number of [N(Bu)₄]X, where X is fluoride (F⁻), chloride (Cl⁻), bromide (Br⁻), iodide (l⁻), acetate ( Ac⁻), hydrogen sulphate (HSO₄⁻), hexafluorophosphate (PF₆⁻). The equilibrium constants were valuated using singular value decomposition, or global analysis. The analysis suggests a complex equilibrium consisting of eight distinct species in the ground stat. For the excited state bbim a similar analysis describe above yielded six step equilibra. The potential application of bbim as a anion sensor which can discriminate the anion however this compound are air sensitive when excited in present of air. -- A second distinct study was focused on the 3-aminocoumarin (3-AC). The emission spectral fitting results were consistent with a small change in the structural in the ground and excited state. This study was first to use emission spectral fitting as a tool to probe the excited state and was consistent with expectation of the energy gap law was obeyed. At the present time more experiments are required to understand the position of substituent and the nature of emitting state. The data suggests the intervention of a ICT and TICT state in excited state decay. DFT calculations were carried out to understand the electronic structure in the ground state.


identifier: Eggleston, Cari <https://research.library.mun.ca/view/creator_az/Eggleston=3ACari=3A=3A.html>   (2010) Ecology of Norway Rats (Rattus Norvegicus) in relation to conservation and management of seabirds on Kiska Island, Aleutian Islands, Alaska 2005-2006.  Masters thesis, Memorial University of Newfoundland.

abstract: Historical invasions by introduced species into formerly pristine ecosystems present a case where damage and change must often be measured indirectly. Long-term monitoring of demographic parameters has been used to infer trends of the auklet colony at Sirius Point, Kiska Island Alaska in relation to predation by introduced Norway rats (Rattus norvegicus). In 2001 and 2002 the auklet colony experienced the lowest reproductive success ever recorded for auklets. Norway rats have been suggested as the cause for auklet reproductive failure due to anecdotal evidence and incidental sign collected at the colony. The first part of my study was to investigate Least Auklet population trends post reproductive failure at Kiska. I found that annual adult local survival estimates for 2002-2005 steadily declined to below 0.8 while reproductive success rebounded to normal levels (54% in 2006). Overall productivity was significantly lower at an island with rats (Kiska) as compared to islands without rats (Kasatochi: z = 7.24, df = 6, P < 0.0001, Buldir: z = 5.58, df = 6, P < 0.0001). -- The next part of my study aimed to go beyond the previous approach centered on auklet monitoring and focus on Norway rat activity at the auklet colony as well as estimate rat density and develop a method to measure relative abundance. In 2006 radio tracking was used to quantify Norway rat home ranges and movements located near the center of the auklet colony. Rat home range estimates varied from an average of 7713 ± 1978 m² for male rats to 3169 ± 244 m² for female rats. Compared to other islands, home ranges were smaller and density estimates, 12.75 rats/ha, were higher at Sirius Point, with rats living largely underground in the lava dome or tunneling through grass. Rat distribution was patchy - not all habitat types were used equally. -- Three non-invasive index methods (chew sticks, wax blocks and tracking tunnels) were tested to measure Norway rat abundance. Rats were attracted to all indexing methods tested in 2005 and 2006. Fortunately, the most successful method tested, peanut butter flavored wax blocks, also was an easy and inexpensive method to apply in the terrain at Sirius Point, Kiska Island. This method will likely prove to be a good choice to monitor fluctuations in rat populations annually at seabird colonies. Taken together, the results of my thesis work showed that Norway rat activity, while difficult to track and monitor, can be measured using novel methodology that will ultimately contribute to management and conservation of Aleutian Island ecosystems.


identifier: O'Leary, Sheilagh <https://research.library.mun.ca/view/creator_az/O=27Leary=3ASheilagh=3A=3A.html>   (2011) Alternating zonal jets in the oceans: a laboratory study.  Masters thesis, Memorial University of Newfoundland.

abstract: This paper investigates anisotropic oceanic features referred to as zonal jets, zonal meaning that velocity alternates in the east-west direction with latitude.  Zonal jets, as predicted by turbulence theory, were recently observed by satellite altimetry in the world ocean and were observed separately in numerical models of the ocean.  This study is focused on understanding the mechanisms involved in the formation of alternating zonal jets.  Experiments were carried out on a rotating table in the geophysical fluid dynamics laboratory run by Peter Rhines at the University of Washington in Seattle.  A cylindrical tank placed on the table and filled with saline water provides a simplified and controlled environment for modeling the dynamics of oceanic circulation.  The experiments performed for this study demonstrate a mechanism where the jets result from the development of beta-plumes originating from baroclinic instability at the eastern boundary of an ocean.  The underlying dynamics include the propagation of linear and nonlinear basin scale Rossby waves.  The dynamic flow fields were measured by Altimetric Imaging Velocimetry (AIV) and optical thickness methods.


identifier: Eaton, Emily L. (Emily Louise) <https://research.library.mun.ca/view/creator_az/Eaton=3AEmily_L=2E_=28Emily_Louise=29=3A=3A.html>   (2010) Assessing gender bias in acute medical care in Canada.  Masters thesis, Memorial University of Newfoundland.

abstract: Background: Gender bias has been explored extensively in the treatment of cardiovascular disease (CVD), particularly acute myocardial infarction (AMI).  Previous research is inconsistent in suggesting that women who suffer an AMI are treated less optimally than men.  To date, gender bias has not been well addressed in other CVDs, specifically cerebrovascular accident (CVA), coronary revascularization, or chronic kidney disease (CKD).  In an attempt to get a clearer grasp of the problem, community acquired pneumonia (CAP) was also studied and served as a non-vascular disease control. -- Methods: Using trained research nurses, retrospective chart reviews were completed for all patients admitted with AMI, CVA, for coronary revascularization, or CAP in 1995/6, 1998/9, and 2000/1 in two locations of Newfoundland (St. John's and Central Newfoundland).  CKD care was analyzed using data from the STARRT (Study To Assess Renal Replacement Therapy) study, a Canadian multicentre retrospective chart review of incident dialysis patients followed for six months.  All results were divided into three categories - access, intervention, and outcome - and, after controlling for baseline demographics, were explored for differences in care between men and women. -- Results: Women were often older than men and suffered from more co-morbidities and more severe medical histories, except for CAP where men were more likely to have co-morbid illnesses.  Women who had suffered an AMI had a significantly longer time to thrombolytics (70 vs. 45 mins., p=0.02) and were less likely to be admitted to the CCU (84% vs. 91%, p=0.02).  Women with severe CAD were more likely to receive medical management (42% vs. 28%, p=0.005) and, of the women who did receive CABG, had longer wait times in one priority for CABG group (8.0 vs. 6.0 days, p=0.05).  Women began dialysis with a lower eGFR level (8.6 vs. 10.1 mL/mins., p=0.006) after receiving less pre-dialysis care than men (>1 mth. vs. <1 mth.) (80% vs. 88%, p=0.05).  There was no evidence of a gender bias against women in CVA patients, in fact women were more likely to be seen by a social worker than men (43% vs. 34%, p=0.01).  Of the patients receiving treatment for CAP, women were less likely than men to receive the appropriate antibiotics (AB) when considering the 1993 guidelines for AB treatment (70% vs. 78%, p=0.03).  While women received less optimal access and interventions, the proportion of death between men and women for all CVDs analyzed were similar. -- Conclusions: Women are not treated with the same quality of care as men with regards to access and intervention for AMI's, coronary revascularization, and CKD.  This bias was also found in a nonvascular control group.  A potential gender bias in the treatment of these patients needs to be explored further.


identifier: Su, Jianmin <https://research.library.mun.ca/view/creator_az/Su=3AJianmin=3A=3A.html>   (2010) Extending the instance-based data model : semantics, performance and security considerations.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Current databases are typically designed for particular predetermined purposes.  However, users may need to use the same dataset for multiple and changing purposes, some of which may not be known when the database is designed.  To handle multiple purposes in traditional data models, it is often necessary to construct multiple databases or views.  When new information needs arise, additional databases or views may need to be constructed. -- The instance-based data model (IBDM) supports instances independent of any classes to which those instances might be assigned.  The model adopts a two-layer approach to data organization (instance layer and class layer), so that an instance may belong to more than one class or, alternatively, none of classes defined in a database schema.  The model makes it possible to construct multiple and flexible schemas for a dataset to support multiple and changing needs of users.  However, previous research on the instance-based model does not address a number of issues related to the strengths of separating instance and class layers in the IBDM in fulfilling the needs of particular applications, including supporting database administration issues such as providing more flexible security policies. -- In this thesis, we propose theoretical and practical enhancements to the instance-based model.  First, we extend the semantics and implementation methods of data expressed in the instance-based model.  The semantic extension of components of the instance-based model clarifies the definition of the model and the implementation of the components simplifies applications to real database systems.  Second, we provide a theoretical comparison and an empirical simulation to show that the instance-based model is more efficient than the relational model on some typical queries.  Third, we propose a security model to address security issues in multilevel security applications using the instance-based approach.  To ensure the model's security, we also provide operating methods and rules for the proposed model.  Finally, we evaluate the proposed model and prove that the model is secure.  By applying the instance-based model to the multilevel security area, the research forms the foundation for using the instance-based model to construct multiple schemas and to support multiple applications.


identifier: Flynn, Matthew T. (Matthew Thomas) <https://research.library.mun.ca/view/creator_az/Flynn=3AMatthew_T=2E_=28Matthew_Thomas=29=3A=3A.html>   (2011) Discrete cosine transform based feature extraction for computer aided detection of suspicious x-ray mammogram images.  Masters thesis, Memorial University of Newfoundland.

abstract: One of the best ways to decrease breast cancer mortality is through early detection.  X-ray mammography is widely used to screen women with an increased risk of breast cancer.  Computer aided detection (CAD) programs have been developed in an effort to boost efficiency and accuracy, but studies have shown that the CAD programs currently in use are not particularly effective. -- In this project, a new CAD algorithm was developed.  The two main components of the method were the use of whole image classification and a novel feature extraction step using the discrete cosine transform.  The features were generated from moments of the mean of square sections centered on the origin of the transform.  Feature vectors were then run through k-nearest neighbour and naive Bayesian classifiers. -- It was found that the discrete cosine transform could be used to manually filter suspicious characteristics from images.  Features extracted from the images were found to change dramatically when a mass was introduced into the image.  Using a k-nearest neighbour classifier, sensitivities as high as 98% with a specificity of 66% was achieved.  With a naive Bayesian classifier, sensitivities as high as 100% were achieved with a specificity of 64%.


identifier: Normore, Jason <https://research.library.mun.ca/view/creator_az/Normore=3AJason=3A=3A.html>   (2010) Efficient computational fluid dynamics methods for GPGPUs.  Masters thesis, Memorial University of Newfoundland.

abstract: Computational fluid dynamics (CFD) is an area of fluid mechanics that involves using numerical methods to solve fluid systems.  Most practical CFD problems involve solving a minimum of two nonlinear coupled partial differential equations, which is computationally expensive for practical fluid systems.  The methods proposed in this thesis take advantage of the parallelism of the graphics processing unit (GPU) to increase the efficiency of two CFD techniques for general purpose fluid flow simulations.  The improved techniques produce very good results for increased efficiency, while keeping the overall methods practical and able to run on readily available and inexpensive GPU hardware.  We discuss the advantages and disadvantages of the techniques developed, along with how different techniques affect the results, applications of the developed methods, and possible extensions to the methods.


identifier: Pitcher, Jill Cicely Ann <https://research.library.mun.ca/view/creator_az/Pitcher=3AJill_Cicely_Ann=3A=3A.html>   (2011) Applying social science methods to visitor research in Terra Nova National Park.  Masters thesis, Memorial University of Newfoundland.

abstract: Canada's national parks are mandated to protect both the natural and cultural significance of the unique places they represent.  Each national park is required to evaluate the outcomes of their external communications strategies.  Social science research methods were applied to the evaluation of park communications to key audiences in Terra Nova National Park (TNNP), Newfoundland.  Data collected through a questionnaire were used to measure the effectiveness of the parks communications to its two critical audiences: visitors and community residents.  Data were analyzed relating to the understanding of the three main interpretative themes of the park: Canada's national park system, local issues in TNNP and ecological issues in TNNP.  Research results indicate that visitors are more likely to avail of the parks educational programming than community residents and that community resident believe the experiences offered in national parks can be found elsewhere.  Visitors demonstrated significantly more positive attitudes towards national parks and TNNP, although both audiences demonstrated a generally positive attitude.  Visitors also demonstrated consistently higher levels of knowledge than community residents although knowledge of ecological issues was weak among both groups.  The values exhibited do suggest that national parks are perceived to be of great benefit to both key audiences.


identifier: Sanders, Robert Alan <https://research.library.mun.ca/view/creator_az/Sanders=3ARobert_Alan=3A=3A.html>   (1977) Alexander John Ellis: a study of a Victorian philologist.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Symbols, both graphic and mathematical, exercised a lifetime fascination for the Victorian scholar, Alexander John Ellis (1814-90) in connection with his investigations into spelling reform, phonetics, mathematics, physics, and particularly philology.  In conjunction with the phonographer Isaac Pitman, he undertook during the 1840's to revolutionize reading instruction for the illiterate masses by utilizing a special phonotypic alphabet.  In 1866, Ellis devised Palaeotype, a system of sound notation employing combinations of existing type faces to represent minute phonetic distinctions.  Ellis then constructed an account of the evolution of English speech sounds through the course of twelve centuries in his monumental study On Early English Pronunciation (1867-89).  Central to his account are his conjectured pronunciations of the sounds represented in the texts of Chaucer and Shakespeare.  Expanding his investigation, Ellis conducted the first dialectal survey of the British Isles and drew the first reliable map of English dialectal boundaries.  This landmark in English dialectal history was based upon dialect tests, comparative specimens, word lists, and viva voces.  Providing assistance and encouragement with the complex survey were Thomas Hallam, Prince Louis Lucien Bonaparte, J.G. Goodchild, and hundreds of dialectal informants.  In order to preserve the nation's vanishing dialectal forms, in 1871 Ellis took the lead in establishing the English Dialect Society, whose efforts later were the basis for Joseph Wright's great English Dialect Dictionary.  Ellis likewise conjectured the sounds of both Latin (1874) and Greek (1876).  His vigorous leadership in the affairs of the Philological Society of London brought him into close contact with scholars like F.J. Furnivall, James A.H. Murray, William Aldis Wright, Francis J. Child, and Henry Sweet.  Ellis figured prominently in those events leading to the publication of the Oxford English Dictionary, undertaken by the Philological Society.  Extensive studies into theoretical mathematics, particularly his work on stigmatics, earned for him the admiration of his colleagues in the Royal Society of London.  His experiments regarding the nature of pitch in organs included a major revision and translation of Helmholtz's study Tonempfindungen (1875) and a scientific determination of the scales of non-European instruments (1885).


identifier: Harding, Meghan L. (Meghan Lucy) <https://research.library.mun.ca/view/creator_az/Harding=3AMeghan_L=2E_=28Meghan_Lucy=29=3A=3A.html>   (2010) A behavioral investigation of L-type Ca²⁺ channel subtypes Caᵥ1.2 and Caᵥ1.3 in Nicotine addiction.  Masters thesis, Memorial University of Newfoundland.

abstract: Nicotine has become one of the most addictive and devastating drugs in recent history. Not only has chronic nicotine use, by way of smoking, been linked to cardiovascular problems, cancer and lung diseases from bronchitis to lung cancer, but it kills 40,000 Canadians every year. The mesolimbic dopaminergic pathway has been primarily associated with addiction: cells in the ventral tegmental area release dopamine in the nucleus accumbens, which leads to memory and addiction formation. Previously, our lab investigated what initiates burst firing of ventral tegmental area dopamine neurons when cholinergic nicotinic receptors are activated, as burst firing leads to a higher release probability than spike firing. L-type calcium channels have been shown to be crucial in ventral tegmental area dopamine cell burst firing induced by cholinergic activation. While in vitro work in our lab undoubtedly indicates L-type calcium channels mediate burst firing of dopamine cells, the question of whether they also mediate nicotinic activation of the central dopamine system in behaving animals remains open. -- Nicotine is known to decrease anxiety in chronic smokers and is generally followed by anxiogenic side effects upon sudden nicotine cessation, as seen most often with smokers quitting. In order to test what role L-type calcium channels have in nicotine addiction, two transgenic mice models were tested, one lacking the L-type calcium channel subtype Caᵥ1.3 (Caᵥ1.3-/-) and the other having a mutated DHP site in the Caᵥ1.2 alpha subunit (Caᵥ1.2DHP-/-). We tested Caᵥ1.2DHP-/- mice in the elevated plus maze to examine how L-type calcium channels affect anxiety levels following nicotine treatment and blockade of the Caᵥ1.3 subtype. The conditional place preference test allowed us to investigate the addictive properties of nicotine in the two transgenic mouse models and how L-type calcium channel antagonists (nifedipine) would affect them. -- The elevated plus maze revealed that Caᵥ1.2DHP-/- had different baseline anxiety levels compared to wildtype mice. Nicotine was anxiolytic acutely (following one day of treatment) in Caᵥ1.2DHP-/- mice, while in wildtype mice repeated nicotine was seen to induce anxiolytic effects. Upon the application of nifedipine, an L-type calcium channel DHP antagonist (which mechanism of action only is able to block Caᵥ1.3 due to Caᵥ1.2 mice being DHP insensitive), wildtype mice showed a further decrease in anxiety, while Caᵥ1.2DHP-/- showed no change, indicating that Caᵥ1.3 subtype may play a lesser role in anxiety than Caᵥ1.2. -- Wildtype and Caᵥ1.2DHP-/- mice showed a strong nicotine place preference (time spent in the drug conditioned arm over the neutral arm) of approximately 100 seconds. Nifedipine pretreatment in Caᵥ1.2DHP-/- and wildtype (which blocked both Caᵥ1.2 and Caᵥ1.3) mice abolished the conditional preference for nicotine, suggesting Caᵥ1.3 mediated nicotinic preference. However, when Caᵥ1.3-/- mice were tested for nicotine preference, their conditioned place preference was similar to that in wildtype and Caᵥ1.2DHP-/- mice. Further work is needed to understand the differential involvement of these subtypes in nicotine-induced place conditioning. -- In conclusion our results indicate that the L-type calcium channel subtype Caᵥ1.2 may be more actively involved in anxiety, while Caᵥ1.3, when present, appears to be more critical in inducing nicotine preference. Failure to confirm this finding in Caᵥ1.3-/- mice may be due to compensatory changes in other L-type subtypes or redundant reward circuitry.


identifier: Begum, Afroza <https://research.library.mun.ca/view/creator_az/Begum=3AAfroza=3A=3A.html>   (2011) Electrochemical CO2 reduction.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

title: Electrochemical CO2 reduction

abstract: Electrochemical methods for CO₂ reduction have been receiving continuous attention for the last few decades mainly for the conversion of CO₂ to fuels as an alternative global energy source and the inexpensive production of carboxylated products for industrial applications. CO₂ is considered as a greenhouse gas, whose increasing concentration in the atmosphere is a growing environmental concern. The main obstacle for the direct electrochemical reduction of CO₂ is the requirements of very high negative standard potential as high as -2.21 V vs SCE. Several transition-metal based molecular catalysts, for example, ruthenium polypyridyl complexes, were reported to convert CO₂ to fuels, such as methanol, formic acid, oxalic acid, methane etc., at a lower cathodic potential. On the other hand, electrocatalytic conversions of CO₂ using aromatic ketones were also found to be useful in the syntheses of medicinally useful materials, such as 2-arylpropanoic acids and Î±-oxocarboxylic acids (as anti-inflammatory drugs), agricultural chemicals and perfumes. A number of monometallic and bimetallic ruthenium benzimidazole and benzothiazole based polypyridyl complexes were synthesized in this work that were found to be operate as electrocatalysts for CO₂ reduction at reasonable cathodic potentials. These complexes were characterized by cyclic voltammetry (CV), electronic absorption (UV-Vis) and emission, X-ray diffraction (XRD) techniques. -- Electrolysis of the complexes was performed to reveal their electrocatalytic effect on CO₂ reduction. Product analysis by high-performance liquid chromatography (HPLC)/UV-Vis methods revealed that formate and oxalate are detectable in addition to some other products. In this study, it was found that structural variations in the electrocatalyst could influence the activity, however all benzothiazole containing complexes exhibited much higher activities than those of the corresponding benzimidazole complexes. Formate and oxalate were produced and detected at moderately low cathodic overpotentials for [{(bpy)₂Ru}₂(py₂tbtz)]⁴⁺. This is an unprecedented result for benzothiazole complexes. In addition, the electrochemical reduction of CO₂ by fluorenone-9-one was found to produce 9-hydroxyfluorene and 9-hydroxyfluorene-9-carboxylic acid, in addition to formate and oxalate at a low cathodic overpotential.


identifier: Phillips, Christopher <https://research.library.mun.ca/view/creator_az/Phillips=3AChristopher=3A=3A.html>   (2011) Contributions to the ichnology and ichnofabrics of deep marine systems.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The new data presented in this thesis demonstrates that detailed palaeoenvironmental reconstructions of deep marine and turbidite settings are improved with the integration of ichnofabric analysis. This thesis is divided into three papers; each using ichnofabric analysis in end-member sedimentological, deep-water systems. In addition, neoichnological research conducted as part of this project links modern and ancient tracemaker behaviour to provide a new model for a commonly observed trend in trace fossil distribution in deep-water settings. -- Facies analysis was integrated with ichnofabric analysis in the Eocene/Oligocene sand-rich turbidites of the Grés d'Annot Basin, SE France. Bed-by-bed logging demonstrated that ichnofabric analysis can be used as a high resolution tool for reconstructing depositional palaeoenvironments and their variability in deep-water systems. The Ophiomorpha rudis ichnofabric association (analogous to the Ophiomorpha rudis ichnosubfacies of the Nereites ichnofacies) are present in deposits of high current energy settings and low nutrient levels like channelized sands and thick-bedded turbidites in the Grés d'Annot Basin. The nature of the Grés d'Annot Basin as a thrust sheet-top basin confined and channelled the infilling turbidites. This confining of flows suppressed the deposition of thin-bedded and heterolithic turbidites which allow the preservation of a diverse ichnofauna. Low ichnodiversity (restricted to ichnospecies of Ophiomorpha and Thalassinoides) result from a combination of nutrient stress and the confined nature of the Grés d'Annot Basin. When thin-bedded heterolithic turbidites are preserved, however, they contain a higher ichnodiversity, density, and abundance of trace fossils than sand-rich facies. The Ophiomorpha annulata-Planolites and Phycosiphon- Ophiomorpha rudis ichnofabrics represent the activity of vagile, deposit feeding and farming organisms in quiescent basin slope settings and channel fill facies where turbidites of low erosive power allowed the preservation of a greater number of ichnogenera. This paper is the first ichnologically-based study of Grés d'Annot Basin and demonstrates the utility of ichnofabrics in reconstructing palaeoenvironments and changes in depositional conditions. -- Ophiomorpha is commonly observed at sandstone-mudstone interfaces in turbidite systems, including the Grés d'Annot Basin. This paper presents evidence that interface trace fossils represent a deep-sediment farming strategy in deep-water settings with data obtained using mesocosm experiments, CT imagery, and geochemical analyses. The modern thalassinid shrimp Neotrypaea californiensis constructs interface burrows morphologically identical to Ophiomorpha rudis as observed in the Grés d'Annot (and other) systems. Mesocosms were mapped in three dimensions with CT imagery showing that burrows were preferentially constructed at sand-mud interfaces. The characteristic burrow-lining pellets of Ophiomorpha are traditionally considered to be a structural reinforcement to prevent burrow collapse. Our studies have shown that this might not be true in all cases as N. californiensis was observed feeding from the pellets indicating they might be a nutritional resource. Geochemical analyses showed higher total organic carbon values in burrow linings and pellets compared to unbioturbated samples from the same mesocosm. Observation showed that N. californiensis selected organic carbon-rich grains to make the pellets while higher TOC values indicate organic enrichment with burrow walls having an increased bacterial biomass (with bacterially produced dissolved organic carbon). Stable isotope analysis showed that the pellets where generally enriched in ¹³C compared to the isotopically lighter host sediment. This is interpreted as aerobic microbial fractionation. By bioirrigating their burrows N. californiensis (and other ancient Ophiomorpha tracemakers) encouraged the growth of aerobic microbial populations in burrow-lining pellets which they used as a nutritional resource, utilizing microbial dissolved organic carbon. This new data provides a model for the abundance of trace fossils at sandstone-mudstone interfaces in turbidites systems which had hitherto been unexplained. -- The Upper Cretaceous Wyandot Formation, offshore Nova Scotia, is an autochthonous carbonate reservoir facies. This pelagic system was used to demonstrate that ichnofabric analysis can be successfully employed across a range of deep-water palaeoenvironments. The Wyandot Formation is divided into two lithofacies: chalk and marlstone. Ichnofabric analysis showed that the Chondrites-Thalassinoides-Zoophycos ichnofabric dominates both lithofacies. High densities and abundances of ichnotaxa in this ichnofabric, in conjunction with a highly bioturbated mixed layer (BI 5-6), imply a well oxygenated sediment-water interface. Environmental perturbations are interpreted through changes to Chondrites-dominated ichnofabrics. In the Wyandot Formation this resulted from increased sedimented organic matter, causing the redox front to rise in the sediment, leading to porewater anoxia, and the exclusion of all but the stress-tolerant Chondrites tracemaker. This paper successfully tracks changes in the depositional environment of the Wyandot Formation through changes in ichnofabric. A petrographic study of the Wyandot Formation reveals textural and mineralogical differences between burrow fills and host sediment.    It is considered that deposit feeding endobenthic organisms changed the clay mineral assemblages of the sediment by introducing authigenic kaolinite produced during sediment digestion. Burrow fills have a more diverse clay mineral assemblage with a 33% enrichment of kaolinite compared to the host sediment. This is interpreted to be the result of biological weathering and low temperature authigenesis in the digestive systems of the endofauna. This process introduces mineralogical heterogeneity into the Wyandot Formation reservoir facies.  This work improves facies analysis and reservoir characterization in an understudied carbonate system. -- The work on the Grés d'Annot Basin and the Wyandot Formation presented in this thesis are the first ichnologically orientated studies of these deep-water systems.  These data highlight the significance of trace fossil studies in deep-water systems previously understudied with respect to animal-sediment interactions. This thesis also shows that neoichnological research is a useful approach to understanding ancient tracemaker behaviours which can be used to identify palaeoenvironmental conditions.  These papers, individually and cumulatively, demonstrate that ichnofabric analysis can be successfully integrated alongside facies analysis in deep-water systems. The trace fossil record can be used to identify changes in depositional and environmental conditions, as well as identifying physiologically stressed conditions on the ancient deep seafloor.


identifier: Short, Megan M. (Megan Marissa) <https://research.library.mun.ca/view/creator_az/Short=3AMegan_M=2E_=28Megan_Marissa=29=3A=3A.html>   (2010) Coping with negative repetitive thought: an investigation of mindfulness and self-management skills in relation to worry and rumination.  Masters thesis, Memorial University of Newfoundland.

abstract: Extensive comorbidity exists between anxiety and mood disorders (Noyes, 2001).  Forms of negative repetitive thought, such as worry and rumination, have been considered unifying constructs of both disorders.  Current research has examined the efficacy of mindfulness and self-management based therapies on depression and anxiety disorders (Kuyken, Byford, Taylor, Watkins, Holden, White et al., 2008; Wright, Barlow, Turner, & Bancroft, 2003), however, limited research has examined the facets of mindfulness and self-management in relation to the negative repetitive thought styles of worry and rumination.  Examining these relationships will aid in identifying potential therapeutic mechanisms for negative repetitive thought patterns.  Study 1 examined mindfulness and self-management, and their constituent facets, in relation to rumination and worry in an undergraduate sample, and Study 2 examined the relationships between these constructs in a clinical sample.  As expected, worry was highly related to rumination, and mindfulness was highly related to self-management in both samples.  Results from these two studies also revealed that mindfulness, unlike self-management, is independently related to both worry and rumination.  In terms of the individual facets of mindfulness, only acceptance without judgment was significantly related to worry and rumination in both samples.  These results, and their implications, are discussed.


identifier: Vellore, Padmini <https://research.library.mun.ca/view/creator_az/Vellore=3APadmini=3A=3A.html>   (2010) A robust multicast routing protocol for ad hoc networks.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Ad hoc networks are tetherless networks where nodes not only act as source or destination but also as routers on demand. The key features of ad hoc networks (AHNs) include quick deployment and circulation of messages. These features make them well-suited for applications where reliability and robustness are crucial. In such environments, multicasting improves the efficiency of communication by sending information to more than one node in a single transmission. Multicasting in BitTorrent Enabled Ad hoc Network (MBEAN) routing protocol is presented in this research for multicasting in ad hoc networks. MBEAN is based on the concept of BitTorrent protocol, used in peer-to-peer file sharing in the Internet. MBEAN uses a mesh-based approach to establish multiple connections among multicast members in a network. The mathematical framework for member-to-member connectivity, which indicates member reliability, of MBEAN is developed in this research. Analytical explanations for packet delivery ratio and bounds for routing and control overhead are also presented. Simulations conducted show that MBEAN achieves higher member reliability and improved packet delivery ratio with reduced overall overhead compared to other multicast routing protocols such as, Multicasting in Ad Hoc On Demand Distance Vector (MAODV) and Protocol for Unified Multicasting through Announcements (PUMA). The robustness of MBEAN is also demonstrated for realistic application-based scenarios for various kinds of message sources. -- Unicasting in BitTorrent Enabled Ad Hoc Network (BEAN) routing protocol is also presented in this research and is primarily developed to deliver unicast communications in a multicast domain. BEAN protocol applies on-demand methodology and establishes multiple disjoint routes among pairs of nodes. The probability of multiple disjoint paths that are necessary for BEAN is investigated through analytical expressions and validated using simulations. The performance of BEAN in terms of improved delivery of information is illustrated through medium access control mechanism. Simulations are conducted to demonstrate the performance of BEAN under practical network conditions and the results are compared with those of AODV, a traditional routing protocol.


identifier: Cove, Samuel R. (Samuel Robert) <https://research.library.mun.ca/view/creator_az/Cove=3ASamuel_R=2E_=28Samuel_Robert=29=3A=3A.html>   (2011) Design methodology for the control of planar transformer parasitics.  Masters thesis, Memorial University of Newfoundland.

abstract: Planar transformers provide a light-weight and low profile solution for power electronic converters with highly reproducible parameters and simple manufacturability.  Parasitic inductances, capacitances, and resistances in planar magnetics are difficult to model due to the complex interactions between the physical winding arrangement of each layer and the core geometry (track width, air gap, clearance, etc.).  These nonlinear and multivariate magnetic devices play a key role in defining the performance of traditional, soft-switching, and resonant converters by ruling behaviors such as ringing, self-resonant frequency, conduction losses, and current rate of change in these converters.  In this work, a methodology for determining parametric models for leakage and magnetizing inductance, inter and intra-winding capacitances, and winding resistance of small planar transformers is presented using a variety of winding arrangements. -- First, finite element analysis is investigated for the extraction of planar transformer parasitics from 3D designs.  Then a Central Composite Design based on the Design of Experiment (DoE) methodology is employed on finite element simulations to provide comprehensive parasitic models based on winding geometry.  Results from physical verification on a planar ER18/3.2/10 core set are provided and show excellent correlation between models and verification tests.  The method is later employed to effectively design an LLC (inductor-inductor-capacitor) resonant converter, which is also experimentally verified to illustrate the benefits of the proposed method.  The methodology can be employed to characterize and design planar transformers and to predict their performances as part of a variety of power electronic converters.


identifier: Morrison, Connie (Connie M.) <https://research.library.mun.ca/view/creator_az/Morrison=3AConnie_=28Connie_M=2E=29=3A=3A.html>   (2011) Avatars and the cultural politics of representation: girlhood identity in social networking spaces.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Within social media and popular culture, new and diverse forms of online identity representation are emerging in virtual spaces.  As traditional literacy practices yield to newer literacies, these forms of identity representation require and receive critical scrutiny.  Personalized avatars are one such form.  They provide a site through which individuals may represent themselves as a constructed product of identity and the discursive practices that contribute to it. -- This qualitative study explores the cultural politics of representation with ten teenaged girls who constructed personalized avatars for social networking sites.  Its purpose is to investigate the truth effects about representation, girlhood identity and culture, and to analyze the power structures present in the narrative and graphic images of girlhood self-representation.  As part of this analysis, personalized avatars are deconstructed as forms of visual language within a broader context of critical media literacy. -- The ubiquitous character of social networking places girls and their images under a scrutiny within which they become objects of a regulatory gaze.  Drawing from a cultural studies methodology, this study utilizes critical ethnography informed by feminist poststructuralism to examine the politics of this gaze and to articulate the tensions between attempting to be true to lived experience while remaining cognizant of the always partial and ever political nature of representation.  This framework challenges normative notions of the self and attempts to expose how power structures within a site of avatar production intersect with girlhood performative desire. -- This study finds that normative discourses around gender, ability, class, ethnicity, and beauty govern representation for teenaged girls in online spaces in a manner similar to real life locations.  Despite a widely held belief that girls have an expanded capacity to represent themselves through online forums of individual creativity, this study suggests that structures of social media continue to contribute to the power of these regulatory discourses.  This study finds that girls report a constant insecurity and questioning around their self-representations and, as such, these findings have implications for critical media education as well as future research related to girlhood identities in new media spaces.


identifier: Tuziak, Sarah <https://research.library.mun.ca/view/creator_az/Tuziak=3ASarah=3A=3A.html>   (2011) Appetite regulation in winter flounder (Pseudopleuronectes americanus) : characterization of melanin-concentrating hormone (MCH) and gonadotropin-releasing hormone (GnRH) transcript families and their role in feeding behaviour.  Masters thesis, Memorial University of Newfoundland.

abstract: In vertebrates, appetite regulation is a complex process involving both nervous and endocrine systems.  Melanin-concentrating hormone (MCH) and gonadotropin-releasing hormone (GnRH) are two endocrine factors that have been found to regulate food intake in fish and other vertebrates.  These hormones were characterized in winter flounder, Pseudopleuronectes americanus, a flatfish common in Newfoundland bottom waters.  mRNAs encoding several forms of both hormones were identified and shown to be expressed in tissues previously found to be involved in appetite regulation, including the brain (telencephalon, optic tectum, and hypothalamus) and midgut.  Adult fish submitted to fasting displayed higher brain expression levels of transcripts encoding MCH and its receptor, MCH-R1, suggesting that the MCH system might stimulate feeding in flounder.  Conversely, both chicken- and salmon-GnRH mRNA levels were lower in fasted fish suggesting an appetite-inhibiting effect.  Our results suggest that MCH and GnRH, along with their receptors, might play an important role in regulating feeding in winter flounder.


identifier: Hickey, Kelly <https://research.library.mun.ca/view/creator_az/Hickey=3AKelly=3A=3A.html>   (2010) Equality : reaching for the transparent dangling carrot in the words of public sector women.  Masters thesis, Memorial University of Newfoundland.

abstract: This thesis has no abstract