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2024 — Viscosity modeling of solvent-water-heavy oil/bitumen systems at high pressures and elevated temperaturesRésumé
It is widely accepted that enhancing heavy oil/bitumen recovery has become a priority though fundamentally challenging due to the rising oil consumption and gradual depletion of conventional oil. The hybrid solvent-steam injection has been considered to be one of the most important enhanced oil recovery (EOR) methods for a given heavy oil/bitumen reservoir with its main mechanisms related to viscosity reduction resulted from thermal energy as well as solvent dissolution. To quantify the viscosity for such mixtures, various correlations have been proposed but each of them has its own limitations and may lead to large deviations under certain conditions. It … Lire la suite
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2015 — Hexagonal Cylindrical Lattices: A Unified Helical Structure in 3D Pitch Space for Mapping Flat Musical IsomorphismRésumé
An isomorphic keyboard layout is an arrangement of notes of a scale such that any musical construct has the same shape regardless of the root note. The mathematics of some speci c isomorphisms have been explored since the 1700s, however, only recently has a general theory of isomorphisms been developed such that any set of musical intervals can be used to generate a valid layout. These layouts have been implemented in the design of electronic musical instruments and software applications. This thesis presents a new extension to the theory of isomorphic layouts, taking advantage of the repetition of notes in … Lire la suite
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2020 — Evaluation of Liquid and Supercritical Carbon Dioxide Fracturing on Tight Sandstone Oil ReservoirsRésumé
Fracturing technology is an indispensable part in the development of low permeability reservoirs. In order to solve the problems of water consumption and formation damage, carbon dioxide (CO2) fracturing is treated as an alternative formation transformation and production enhancement technology for water-based fracturing. Several researches on fracturing mechanism and advantages of both liquid carbon dioxide (L-CO2) and supercritical carbon dioxide (Sc-CO2) mainly focused on the comparison and analysis of fracturing effects between different fracturing fluids, without evaluating the influence of fluid injection rate and core length for the effects of fracturing. Hence, as the important parameters in fracturing scheme design, … Lire la suite
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2019 — Sequential Approaches to Three-Way Data AnalyticsRésumé
Data analytics is a process to discover useful information in data, draw valuable conclusions, and help users make wise decisions. In most occasions, the conclusions can be formally represented as decision rules in which the left-hand-sides describe conditions and the right-hand-sides give decisions. Ideally, given particular conditions and decisions, the decision rules are expected to indicate definite answers of yes or no. However, definite answers may not be easy to give due to incompleteness, uncertainty, and errors. In such situations, forcing to give definite answers may result in significant mistakes. Instead of bipolar options, a theory of three-way decision allows … Lire la suite
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2014 — Structured Rough Set ApproximationsRésumé
Rough set theory is widely used in many areas, such as artificial intelligence, machine learning and data mining. Lower and upper approximations are two fundamental notions for concept analysis with rough set theory. In rough set theory, one can obtain two kinds of sets in an information table, namely, definable and undefinable sets. Intuitively, a definable set represents some- thing we can describe precisely. On the other hand, for an undefinable set, one cannot describe it precisely due to limited available information. One of the main issues in rough set theory is to approximate an undefinable set by a pair … Lire la suite
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2019 — Utilizing Oil-Soluble Tracers to Evaluate the Production Profile in Multistage Fractured Horizontal WellsRésumé
Multistage hydraulic fracturing along a horizontal well is the key to effectively recover hydrocarbon from tight reservoirs. Improving the hydrocarbon recovery requires detailed production information of each hydraulic fracture. Chemical watersoluble tracers are often used to calculate the production profile from multistage fracturing through tracer flow back test. Unlike conventional water-soluble tracers that are in the form of a liquid, oil-soluble tracers are embedded in the porous media and absorbed on the surfaces of solid carrier particulates. The unique characteristic of oilsoluble tracers is that the tracer will only be released from its carrier particulate when oil passes through and … Lire la suite
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2017 — Cubical Blakers-Massey Theorem for CDGARésumé
We state and prove an algebraic version of the Blakers-Massey Theorem. The Blakers-Massey Theorem is a classical result in homotopy theory that measures the obstruction to homotopy excision. It also measures how far a homotopy pushout square of topological spaces is from being a homotopy pullback. This theorem can be generalized to higher-dimensional cubical diagrams of topological spaces, where it measures how far a cubical homotopy colimit is from being a homotopy limit. This work is inspired by Quillen's rational homotopy theory, where commutative di erential graded algebras (or CDGAs for short) over the eld Q of rational numbers are … Lire la suite
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2020 — Phase Behaviour of Solvent(s)/Water/Heavy Oil Systems at High Pressures and Elevated Temperatures Based on Isenthalpic FlashRésumé
The hybrid steam-solvent injection processes have been proved to be a promising technique for enhancing heavy oil recovery as they combine the advantages from both heat transfer of steam and mass transfer of solvent(s) to further reduce the viscosity of heavy oil. Multiphase isenthalpic flash calculation is required in compositional simulations of the aforementioned processes, which involve vapour, oleic, and aqueous three-phases since water is inevitably associated with steam injection processes. As such, it is of fundamental and pragmatic importance to accurately quantify the phase behaviour of solvent(s)/water/heavy oil systems at high pressures and elevated temperatures by use of isenthalpic … Lire la suite
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2014 — Analysis of Impact Factors for Traffic Noise in urban AreasRésumé
Road traffic noise contributes significantly to outdoor environmental noise, especially in urban areas. The pressure of traffic noise is influenced by many factors such as types of engines, exhaust systems and tires interacting with the road, weather and road conditions. The tire/pavement interaction noise has been proven to be the major source of the traffic noise, especially for cruising driving conditions, which is highly influenced by surface characteristics of road pavement. Traffic flow is also a factor – apart from vehicles, tires and road surface characteristics – in affecting traffic noise pressures. The noise level can increase by about 3 … Lire la suite
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2019 — Development of Experimental and Modelling Approaches to Characterize Noise Reduction Capability of Porous MaterialsRésumé
Porous materials have been recognized as effective materials for noise reduction and noise control. It is also recognized that numerous inherent and external factors may affect the noise reduction properties of porous materials. The research of this dissertation aims to develop innovative experimental and modelling approaches to analyze the noise reduction capability of porous materials under different conditions and to study the main factors affecting the noise reduction capability of porous materials. The impact of material age on noise reduction properties of porous materials is first studied, and a Nested Ensemble Filtering (NEF) approach is proposed for parameter estimation and … Lire la suite
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2023 — Modeling of volumetric changes in cracked expansive soilsRésumé
Extensive damages to civil infrastructure occur due to volumetric deformations in expansive soils. Deformations in this class of sediments are affected by variations in soil properties, surface conditions, antecedent water, and meteorological parameters. Ground shifting is further aggravated by the presences of cracks originating from cycles of hydration-dehydration, freeze-thaw, and glacial advance-retreat. This research is focused on developing a clear understanding of modelling volumetric changes in cracked expansive soils. For this purpose, a representative expansive soil from Regina having a high water adsorption capacity (liquid limit of 77% and plastic limit of 27%) along with hairline cracks was characterized to … Lire la suite
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2015 — Optimization of CO2 Flooding Strategy to Enhance Heavy Oil RecoveryRésumé
Heavy oil is a significant energy resource around the world. In Canada, there are tremendous heavy oil reserves lying in the north of the provinces of Alberta and Saskatchewan. The key point for heavy oil recovery is to increase the mobility of heavy oil in the reservoir condition. The most effective methods of heavy oil recovery are thermal methods such as steam flooding, cyclic steam stimulation (CSS), steam-assisted gravity drainage (SAGD) and in-situ combustion for the great heavy oil viscosity reduction by heat. However, thermal methods are proving to be unsuitable for most of the heavy oil reservoirs in Canada … Lire la suite
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2016 — People's Voices Under Control: An Analysis of Chinese Internet Users and Public Figures' Responses to Media CensorshipRésumé
This thesis explores various aspects of media censorship and surveillance tactics, exercised by the Chinese government, including the establishment of a wide variety of invasive laws and regulations, and the usage of online commentators. The thesis also examines the consequential patterns of reaction, adopted by Chinese Internet companies, regular citizens, and public figures. As a result of extensive literary and field research, this thesis argues that, with the few exceptions of artists and intellectuals, the general public (exemplified by Internet companies and regular users) chooses self-regulatory practices to avoid potential persecution. This, in turn, negatively affects the balance between the … Lire la suite
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2015 — Localization with the EnKF for the Automatic History Matching of the SAGD ProcessesRésumé
The Ensemble Kalman Filter (EnKF) has been successfully applied to data assimilation in Steam Assisted Gravity Drainage (SAGD) processes, but applications of localization for the EnKF in SAGD processes have not been studied. Distance-based localization has been reported to be very efficient for assimilation of large amounts of independent data with a small ensemble in water flooding processes, but it is not applicable to SAGD processes, since in SAGD processes oil is produced mainly from the transition zone from steam chamber to cold oil instead of the regions around the producer. As the transition zone could be identified by saturation … Lire la suite
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2024 — Coping with the distribution change in soil classification with LIBSRésumé
Accurate classification of soil types is crucial for crop productivity. Among the soil analysis techniques, laser-induced breakdown spectroscopy (LIBS) has become a prominent technology for real-time characterization of soil properties. The recent rise in the use of machine learning (ML) techniques for processing LIBS spectra has made LIBS more attractive. However, due to variations in the physical properties and/or chemical composition of the soil samples, the distribution of spectral emission lines can be highly variable, which may lead to different distributions of LIBS spectra and make the training and test spectra not representative of each other. Hence the test performance … Lire la suite
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2014 — “About Average” A Pragmatic Inquiry into School Principals’ Meanings for a Statistical Concept in Instructional LeadershipRésumé
This mixed methods, sequential, exploratory study addresses the problem, “How significant are statistical representations of ‘average student achievement’ for school administrators as instructional leaders?” Both phases of the study were designed within Charles Sanders Peirce’s pragmatic theory of interpretation. In the first, phenomenological phase, 10 Saskatchewan school principals were each interviewed three times and invited to read aloud three different student achievement reports. Principals generally held a “centre-of-balance” conception for the average, which related to perspectives deriving from their organizational position. Abductive reasoning, a proclivity to act upon “below average” student achievement, leadership through asking leading questions, an inquiry cast … Lire la suite
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2012 — An Empirical Study of Health Professionals' Beliefs about Personhood in Dementia and Their Influence on Intended Patient CareRésumé
Three studies were conducted to measure health providers' beliefs about the personhood of long-term care residents with dementia, and the influence of these beliefs on health providers' intended actions toward patients in the long-term care contexts. In Study I, a Likert-format measure of health providers' beliefs about the personhood of long-term care residents with dementia (the Personhood in Dementia Questionnaire) was created after reviewing relevant literature and consulting with health providers. In Study II, this questionnaire was administered to a pilot sample of nurses and continuing care assistants. Psychometric analysis and subject matter expert review were used to reduce the … Lire la suite
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2014 — Thermodynamic and Experimental Studies of Ethane Solubility in Promising Ionic Liquids for CO2 CaptureRésumé
Natural gas is one of the world’s major energy sources and the demand has increased remarkably in recent years. The production of natural gas often requires treatment processes in order to separate CO2 and H2S. CO2 must be removed in order to meet the heating value specifications for sales gas, whereas H2S is removed due to its toxicity and to reduce the overall release of SO2 into the atmosphere during combustion. Ionic liquids have recently been considered the most economically and environmentally friendly solvents for natural gas sweetening. This research aimed at measuring the solubility of C2H6 in six room … Lire la suite
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2020 — A Qualitative Analysis of Facebook Micro-Celebrity: The Case of Qandeel BalochRésumé
This thesis looks at how Facebook (FB) facilitates the transformation of micro-celebrities such as Pakistani social media micro-celebrity Qandeel Baloch, into embodiments of notoriety, and examines the mechanism through which the newly acquired fame destroys them. Predicated on the shifts and changes in celebrity culture in general, the microcelebrity model constructed in this thesis, reveals how online self-presentation, facilitated by FB, has evolved into a set of behaviors, or celebrity performative practices, driven by self-importance and narcissism, resulting in the rapid proliferation of fame to non-exceptional people on FB. In addition to speculative techniques like intimacy, emotionalization, dramatization and self-sexualization, … Lire la suite