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This dissertation studies how nanoadditives influence burning rates through the development and use of a model to conduct parametric studies on nanoadditive interaction and to formulate theories. Decades of research have yet to determine the specific mechanisms for additive influence and the theories remain diverse and fragmented. It has been theorized that additives catalyze the combustion and thermal decomposition of AP, influence the condensed phases, and enhance the pyrolysis and regression of the binder. The main focus of the thesis was to approximate the enhanced boratory using spray-dried, spray-dried/heat-treated, and premixed TiO2 nanoadditives with ammonium perchlorate (AP) / hydroxyl-terminated polybutadiene (HTPB) composite propellants. The model is based on the classic Beckstead-Derr-Price (BDP) and Cohen-Strand models and contains a component that determines the pressure changes within the strand burner during a test. The model accurately predicts measured burning rates for baseline propellants without additives over a range of 500 - 3000 psi within 10%. The strand burner component of the model predicts the experimental pressure trace accurately. Further, the strand burner component determines an average burning rate over time and predicts a transient burning rate if provided a pressure trace. A parametric study with the model parameters determined that the nanoadditives appear to be increasing the AP condensed phase reaction rate. This conclusion was drawn because only changes in AP condensed-phase reaction rate would adequately and realistically replicate burning rate enhancements seen in laboratory experiments. Parametric studies with binder kinetics, binder regression rate, AP surface kinetics, and primary flame kinetics produced burning rate behavior that did not match that seen in experiments with the additives. The model was further used to develop a theory for how the nanoadditive affects the AP condensed phase, and a new parameter, (Omega)c, that influences the AP condensed phase reaction rate was created that replicates spray-dried, spray-dried/heat-treated, and premixed TiO2 nanoadditive experimental burning rates. Finally, the model was used to develop a first approximation of predicting anomalous burning rate trends such as a negative pressure dependence and extinguishment. A new term, Mc, that modifies the ratio of binder mass flux to oxidizer mass flux is used in tandem with (Omega)c to develop a negative burning rate trend that is close to the experimental result.

Industrial robots are the most widely manufactured and utilized type of robots in industries. Improving the design process of industrial robots would lead to further developments in robotics industries. Consequently, other dependant industries would be benefited. Therefore, there is an effort to make the design process more and more efficient and reliable. The design of industrial robots requires studies in various fields. Engineering softwares are the tools which facilitate and accelerate the robot design processes such as dynamic simulation, structural analysis, optimization, control and so forth. Therefore, designing a framework to automate the robot design process such that different tools interact automatically would be beneficial. In this thesis, the goal is to investigate the feasibility of integrating tools from different domains such as geometry modeling, dynamic simulation, finite element analysis and optimization in order to obtain an industrial robot design and optimization framework. Meanwhile, Meta modeling is used to replace the time consuming design steps. In the optimization step, various optimization algorithms are compared based on their performance and the best suited algorithm is selected. As a result, it is shown that the objectives are achievable in a sense that finite element analysis can be efficiently integrated with the other tools and the results can be optimized during the design process. A holistic framework which can be used for design of robots with several degrees of freedom is introduced at the end.

The mobile era is well established and the number of smartphone users is showing exponential growth. The capability of smartphones and enabling technologies is also increasing and has opened many possibilities of personalized mobile services. The goal of personalization is to support the user by providing the right service at the rightmoment. Early focus of personalization was on content adaptations in different information systems. The new approaches of personalization are still needed for mobileservices as it is a compelling feature of mobile communication systems for both endusers and service providers.Personalization is providing a means of fulfilling users’ needs more effectively andefficiently and, consequently increasing users’ satisfaction. By providing successfulpersonalization, a high degree of user satisfaction and a pleasant user experience can beachieved. Some features of personalization can cause problems and may outweigh thebenefits of personalization.This thesis has focused on how to achieve scrutable mobile client-side personalizationwhile keeping the user’s privacy. The issue of privacy in personalization of mobileservices can be reduced by shifting the control of their personal information towards theusers. Our research goal is to understand and improve the personalization process anddevelop an architecture for scrutable mobile client-side personalization while keepingthe user s’ privacy. Moreover, there is a need to develop an evaluation framework tomeasure the effectiveness of mobile services personalization. A design science researchmethodology is adopted in this research work. More particular contributions of thethesis are as follows: C1: Identifications of the research issues and challenges in personalization of mobileservices. C2: An approach for delivering personalized mobile services. C3: Development of mobile client-side personalization architecture. C4: Development of mobile services Personalization Evaluation Model. C5: Identification of the prospects of scrutable personalization of mobile services.

One of the consequences of competitive electricity markets and international commitments to green energy is the fast development and increase in the amount of distributed generation (DG) in distribution grids. These DGs are resulting in a change in the nature of distribution systems from being "passive", containing only loads, to "active", including loads and DGs. This will affect the dynamic behavior of both transmission and distribution systems. There are many technical aspects and challenges of DGs that have to be properly understood and addressed. One of them is the need for adequate static and dynamic models for DG units, particularly under unbalanced conditions, to perform proper studies of distribution systems with DGs (e.g., microgrids). The primary objective of this thesis is the development and implementation of dynamic and static models of various DG technologies for stability analysis. These models allow studying systems with DGs both in the long- and short-term; thus, differential and algebraic equations of various DGs are formulated and discussed in order to integrate these models into existing power system analysis software tools. The presented and discussed models are generally based on dynamic models of different DGs for stability studies considering the dynamics of the primary governor, generators, and their interfaces and controls. A new comprehensive investigation is also presented of the effects of system unbalance on the stability of distribution grids with DG units based on synchronous generator (SG) and doubly-fed induction generator (DFIG) at different loading levels. Detailed steady-state and dynamic analyses of the system are performed. Based on voltage and angle stability studies, it is demonstrated that load unbalance can significantly affect the distribution system dynamic performance. Novel, simple, and effective control strategies based on an Unbalanced Voltage Stabilizer (UVS) are also proposed to improve the system control and the stability of unbalanced distribution systems with SG- and DFIG-based DGs.

Vector Fitting is employed to approximate the Frequency Response Analysis (FRA) measurement data of a 13.8 kV/136.8 kV, 50-MVA single phase transformer. The frequency response of the primary and secondary coils as well the coupling between the coils have been measured in the frequency range of up to 2 MHz. The measured data includes the stray capacitances that exist between the coils. A circuit synthesis model is used to represent the measured data in the form of a two-port passive RLC network. The derived network is implemented in a commonly used power system transient simulator (PSCAD/EMTDC). The proposed RLC model is passive to ensure the stability of the network. The model can be used to investigate transient response of the transformer including the simulation of switching and lightning overvoltage transients. The results are compared with those derived from existing simple models.

Tillage erosion is a major contributor to the total soil erosion in cultivated topographically complex lands. No study has been carried out on tillage erosion associated with cereal-based production systems in the Canadian Prairies, and there is a need to examine tillage erosivity of secondary tillage and seeding implements and the effect of slope curvature on tillage translocation. With both tillage and water erosion occurring in a cultivated topographically complex landscape, it is valuable to investigate the relative contributions of and the possible linkage and interactions between these two erosion processes. Tillage translocation causes the mixture of subsoil into the till-layer, which may considerably affect soil properties and therefore the related biophysical processes. In this study, using plot tracers, we examined tillage translocation caused by four tillage implements: air-seeder, spring-tooth-harrow, light-cultivator and deep-tiller in southern Manitoba, Canada. We determined that secondary tillage and seeding implements could be as erosive as primary tillage implements in a cereal-based production system. In the majority of cases, tillage translocation could be explained by slope gradient alone; however, slope curvature also significantly affected tillage translocation. In two field sites in the North America Great Plains (NAGP), measured 137Cs inventories were converted into total soil erosion rates. Tillage and water erosion rates were estimated using models. The comparisons of the model estimates to 137Cs estimates showed that both tillage and water erosion significantly contributed to the total soil erosion in undulating slopes while tillage erosion was the predominant erosion process in hummocky hilltops. The contributions of and the linkage and interactions between water and tillage erosion showed predictable patterns in different landform elements, with the knowledge of which, landscape segmentation could be used to assess the potential of soil erosion. Further investigation of tillage translocation was demonstrated with four hypothetic landscapes: plane slope, symmetric hill, asymmetric hill and irregular hill, and is tested against field data. A Visual Basic coded program (TillTM) was developed to simulate the redistribution of soil constituents and soil mass. We determined that the pattern of soil mass redistribution was dependent on topography, while the pattern of soil constituent redistribution was affect by topographic features, tillage patterns and temporal scales.

The research was an experimental investigation of the differential effects of various modeling conditions upon self-disclosing behavior. One purpose of the study was to determine whether or not modeling treatments can significantly influence self-disclosure. The second purpose was to evaluate what differences exist in self-disclosure among males and females. Two philosophical assumptions were implicit in the research. The first assumption was that self-disclosure is an essential ingredient for interpersonal adjustment. The second was that self-disclosure is a construct that can be operationally defined and measured. Both assumptions were supported with empirical research.Self-disclosure was defined as an interpersonal process in which a person communicates intimate information and personal feelings or actions to another person. The disclosed information may be past or present and involves a personal risk when the discloser reveals his or her private subjective experiences. The elements of self-disclosure were delineated and a theoretical framework for analyzing the parameters of self-disclosure was discussed. Four measurements were considered essential for obtaining an accurate assessment of self-disclosure. The depth ofdisclosure was evaluated by trained judges who rated audiotapes according to a Revealingness Scale. Duration was assessed by timing the length of each subject disclosure unit. The third measure was the difference on a pre-post "willingness to discuss" instrument. Finallya self-report instrument indicated the subjects' evaluation of their personal disclosures and their partners' disclosures.The population consisted of volunteer undergraduate students enrolled in Introductory Psychology courses at Ball State University. A stratified random sampling procedure was applied to select the subjects from among the volunteers. The subjects were randomly assigned to one of four treatment groups. Each group had eight males and 16 females yielding a total of 96 subjects. The four groups consisted of an intimate in vivo modeling condition, an intimate videotape modeling treatment, a superficial videotape modeling treatment and a control. Each videotape modeling condition consisted of two persons taking turns sharing with each other on intimate topics for about 18 minutes. The in vivo condition involved a model sharing with a subject intimately for about 15-18 minutes. Subjects were exposed to a modeling condition and then requested to pair with another subject and disclose personal information in a structured setting.Two multivariant null hypotheses were tested. The multivariant hypotheses included several sub hypotheses related to each dependent measure of disclosure. The first hypothesis stated that no significant difference in the overall F would exist between the vector of means for males and females. The second hypothesis stated that no significant difference in the overall F would exist between the vector of group means.Multivariate statistical analyses were applied to test the null hypotheses. No significant differences were found among the four groups on any of the disclosure parameters. Likewise, males and females did not differ in self-disclosure. Several a priori hypotheses were analyzed to compare the effectiveness of the modeling conditions. Treatment conditions did not have a differential effect on self-disclosure.Although the overall F was not significant, a significant difference was located through univariate analysis of the sub hypotheses. Male subjects differed from females on the pre-post "willingness to discuss" instrument. Females greatly increased their scores on the posttest, but the scores of the males decreased on the posttest. The difference was significant at the .05 level.The data was further analyzed to explore the relationship between religious commitment and self-disclosure. Three categories of religious commitment were included. Multivariate statistical analysis revealed that subjects indicating strong religious commitment were significantly different on the pre-post measure than subjects in the no religious commitment classification. Deeply religious students increased on the posttest scores while students with no religious commitment decreased. Subjects in the latter category initially perceived themselves as willing to disclose much personal information, but decreased after experiencing the dyadic interactions. The difference was significant at the .025 level.Recommendations and evaluation of the research findings were discussed. Considerations for further research on facilitating self-disclosure through dyadic models were delineated.

Active magnetic regenerator (AMR) refrigeration is an alternative technology to conventional vapor-compression refrigerators that has the potential to operate at higher efficiencies. Based on the magnetocaloric effect, this technology uses the magnetization and demagnetization of environmentally neutral solid refrigerants to produce a cooling effect. To become competitive however, a large amount of research into the optimal device configurations, operating parameters and refrigerants is still needed. To aid in this research, a simplified model for predicting the general trends of AMR devices at a low computational cost is developed. The derivation and implementation of the model for an arbitrary AMR is presented. Simulations from the model are compared to experimental results from two different devices and show good agreement across a wide range of operating parameters. The simplified model is also used to study the impacts of Curie temperature spacing, material weighting and devices on the performance of multilayered regenerators. Future applications of the simplified AMR model include costing and optimization programs where the low computational demand of the model can be fully exploited. / Graduate

We use scaled 3-D thermo-mechanical analogue models to investigate the formation of oroclines (originally linear orogens now curved in map view by buckling about vertical axes). The experimental setup consists of a tank of water (the asthenosphere) on top of which rest hydrocarbon plates (the lithosphere) with strain-softening behaviours and thermo-dependent elasto-plastic properties. An electric heating element below and 4 infrared lights above produce a constant vertical (geo)thermal gradient in the plates. A horizontal piston drives constant plate motion and gives rise to a compressional stress regime. Geometric, kinematic and dynamic variables are calibrated in accordance with a set of scaling laws and proper plate composition. Our results suggest that oroclinal buckling involves the entire lithosphere and cannot be confined to the crust only. A wide range of syn-oroclinal structures developed during buckling, including thin- to thick-skinned thrust belts, transform faults and extensional structures, as well as extensional basins and subduction zones in the lithosphere adjacent to the ribbons. During oroclinal buckling, a thrust belt forms upon complete closure of the interlimb region and is attributable to the trailing orocline limb overthrusting the leading orocline limb. An analogous syn-oroclinal thrust system characterizes the Central Iberian Orocline (CIO) of the Variscan orogen in Iberia where the north limb of the west-convex orocline exposes recumbent north-verging folds while the overriding south limb bears upright to gently north-verging folds. Our results imply that these structures developed during final closure of the CIO, and indicate that the north- and south- limbs of the CIO constitute the leading- and trailing-limbs, respectively, of an orocline that formed by overall northward translation. Modelling of magmatic arcs rotating about vertical axes yields late stage transform faults that bisect the buckling arcs. This outcome is analogous to the Panama Canal fault zone that severs the buckled Panamanian Isthmus. The hinge zones of modeled oroclines are the sites of subduction initiation, similar to subduction initiation of the Caribbean plate beneath the convex to the north, North Panamanian orocline, and of oceanic lithosphere from the Ionian Sea beneath the Calabrian orocline of Sicily. / Graduate / 0372 / gagnonl@uvic.ca