VictorJuiz/thesis huggingface dataset:
An investigation on link level end-to-end power control models in WDM optical networks

An efficient and intelligent resource allocation mechanism is the heart of modern control and management of engineering systems. A dynamic, distributed and online control algorithm is much in need to deal with such Achilles' heel in today's increasingly complex systems. To address this problem, we study the ubiquitous network systems and, in particular, WDM optical networks, in the context of coupled channel power resource management, as it represents a rich class of typical nonlinear distributed systems arising from underlying physical constraints. Based previous work on game theoretical approach and direct OSNR optimization technique, this thesis explores at length link level end-to-end power control models from different perspectives.
Monitoring performance during robotic gas metal arc short-circuiting welding

In this project, the output of current and voltage of gas metal arc welding (GMAW) is recorded and analyzed by data acquisition and analysis system. The images of welding process are also captured by high-speed camera. An algorithm was developed which uses minimum current; that is, characteristics points of welding current output, as a signal to monitor short-circuiting welding performance. This algorithm reflects the relation among minimum current, wire feed speed, voltage and tip-to-work distance. It is capable of checking the situations that shielding gas composition is changed, shielding gas is interrupted, there is heavy oil on sheet and main welding parameters are changed by chance. It is made possible to automatically detect some undesirable welding conditions. It also seems possible to use the combination of minimum current and short-circuiting resistance to monitor and partly control real time short-circuiting welding process in the future.
Genetic oscillator design

The design, simulation, and analysis of a genetic oscillator are presented. The genetic oscillator uses hysteresis in a fashion similar to one model of a circadian oscillator and bistable electronic oscillators. A deterministic and a stochastic model of the genetic oscillator were developed. Changes to the initial parameters and topology were required for the system to oscillate. The effects of small parameter variations and initial conditions were examined. Some parameter values resulted in clean oscillations and others resulted in the absence of oscillations. The initial concentration of one particular protein could cause a large transient. For some parameter values, a background reaction that did not alter the molecule count was necessary for the stochastic model to produce oscillations. Oscillators such as the one presented here may eventually be used to synchronize cellular activities.
Small area coating weight distribution

Paper is often coated to improve its printability. However, nonuniformities in the coating layer could result in poor print quality. The existing techniques for assessing coating uniformity fail to provide quantitative information at a high resolution. In this study, a method is developed to determine the coating weight distribution with a resolution of 100 mum using Fourier Transform infrared (FTIR) microspectroscopy. Both polyethylene terephthalate (PET) films and Thermomechanic pulp (TMP) paper were coated with a range of coating weight and formulations. The samples were scanned under an FTIR microscope. Different spectral filtering methods were used to reduce the noise in the spectrum. The spectra were correlated to the coating weight using partial least square (PLS) technique. These PLS models were able to predict the coating weight with a root mean square error better than 4.1 g/m2. However, it was found that PLS model predictions for PET films were generally better than those of TMP paper. It was also found that roughness had a significant impact on spectral data and on the model performance.
Earnings distortion and CEO compensation

This thesis tests multitask agency theory in which the agent has multi-dimensional tasks and both an undistorted and a distorted performance measure are available for contracting. Accounting earnings is modeled as a distorted performance measure and stock returns as a relatively undistorted measure. First, I demonstrate that the marginal products of CEOs' earnings management actions with respect to accounting earnings, in general, are not equal to the marginal products of their earnings management actions with respect to stock returns. In doing so, I provide evidence in support of the hypothesis that accounting earnings is a distorted performance measure because of CEOs' earnings management actions. This distortion measure is then used to investigate cross-sectional variation in the relative sensitivity of CEO compensation to accounting earnings. I find that the weight placed on accounting earnings relative to stock returns in CEO compensation decreases as earnings distortion increases. Overall, the results provide evidence consistent with multitask agency theory, which predicts that optimal compensation contracts put less weight on the distorted performance measure as its distortion increases in order to improve the efficiency of CEOs' effort allocation across tasks.

Keywords: Accounting
Dissertations, Academic, Canada
Mechanical and thermal properties of nanostructured nickel-phosphorus alloys at grain sizes below 30 nm

Despite the numerous past studies on nanocrystalline materials, the effects of grain size on many properties are still not well understood, mainly because of uncertainties associated with sample imperfections (e.g. pores and cracks), contamination, compositional variations with grain size and the contribution of interfaces. In this study, a structure model is first presented for the calculation of the interfacial volume fractions in such materials. Fully-dense Ni-P samples were then electrodeposited with a relatively constant P content ( sim;2.5wt%) and a 4-30 nm grain size range to measure the following properties: Young's modulus, thermal stability and heat capacity. It was shown that for grain sizes larger than 18 nm, the Young's modulus is independent of grain size ( sim;200GPa). However, for grain sizes less than 18 nm, the Young's modulus decreased continuously towards the value of an amorphous Ni-P structure (144 GPa). It is shown that this is due to the substantial contribution of the interface structures, i.e. the excess free volume in the interface regions, as measured by positron annihilation lifetime spectroscopy. The hardness obeyed the classical Hall-Petch relationship for grain sizes larger than 7 nm with a positive slope of 0.36 MPa-m0.5, but decreased with a negative slope of -0.17 MPa-m0.5 for grain sizes less than 7 nm. During calorimetric annealing, two distinct exotherms, heat releases I and II, were observed. During heat release I, strong grain boundary drag by P solute was found to account for the substantial thermal stability up to 400°C. During heat release II, massive grain growth occurred concurrently with the formation of Ni3P particles, demonstrating a weaker grain boundary drag by particles at higher temperatures. The activation energies for abnormal and normal grain growth were determined to be 1.49 eV and 2.4 to 2.6 eV, respectively. The isobaric heat capacity in the temperature range from 50°C to 120°C was close to the experimental values previously reported for polycrystalline materials, indicating no significant grain size effect.
Assessment of caffeine as a probe for CYP1A2 activity

The overall objective of this thesis was to assess caffeine as a suitable probe for CYP1A2 activity. The first aim of these in vivo studies was to compare two established caffeine-based methods as indices of CYP1A2 activity. The methods were referred to as the paraxanthine-caffeine urinary ratio (POUR) and the caffeine metabolite ratio (CMR). The second aim was to examine the effect of theobromine intake on caffeine metabolism. The in vitro studies were devoted to further evaluating the roles of CYP1A2 and possibly other P450s in the biotransformation of caffeine. The results of in vivo studies fully demonstrated that CMR correlated significantly better with the systemic clearance of caffeine (CLcaff), which served as a standard of reference for CYP1A2 activity than did PCUR. The results of in vitro studies indicated that various cDNA expressing systems for individual human P450s gave rise to different metabolite profiles and kinetic parameters for caffeine biotransformation. Caution is therefore required in choosing a reliable system to study the role of individual P450s in the biotransformation of caffeine. (Abstract shortened by UMI.)
Illness, self, and care: Life experiences of people living with HIV/AIDS in China

Of the currently estimated 650,000 HIV/AIDS cases in China, the majority of this population remains invisible (MOH, UNAIDS WHO, 2006). Research on HIV/AIDS in China has paid disproportionate attention to HIV prevention and control, while little is known about the life experiences (e.g., decision-making, health practices, and coping) of people living with HIV/AIDS (PLWHAs). This dissertation explores the complex processes in which Chinese PLWHAs live and make sense of their everyday lives, shedding light on how this global epidemic has local impacts, at both micro and macro levels. Using a phenomenological approach, the data for this qualitative study were collected through semi-structured in-depth face-to-face interviews with 10 frontline professionals working with Chinese PLWHAs and with 21 adult PLWHAs in China. The findings of this study reveal that the social and health consequences of HIV/AIDS in China, as in many other places in the world, have been disproportionately borne by those who are already disadvantaged due to their socio-economic status, migrant status, sexual orientation, gender, age, ability, and other social dimensions. The socio-cultural meanings of HIV/AIDS in China and the increasing complexity and diversity of local experiences in dealing with this disease calls into question the "universality" of HIV/AIDS knowledge in biomedical discourses. It suggests that Chinese PLWHAs' experiences must be understood from a broad perspective that can articulate micro-macro and local-global connections, and that HIV/AIDS should be responded to in a more comprehensive and collaborative way by mobilizing resources at various levels. This type of knowledge is important for developing more sensitive and responsive policies, programs, and service delivery systems for this population, which, in turn, may improve their access to health services and quality of life in the long term.
Patterning the real: a comparative study between the Sanyan Erpai stories and their wenyan origins in the ming period

This thesis is a comparative study of two groups of texts about the same story written in almost the same period. One is the group of baihua (vernacular) stories from the Sanyan Erpai collections written by two major late Ming mimetic huaben writers: Feng Menglong and Ling Mengchu. The other is from various chuanqi and jotting collections that are the sources of the above stories written in wenyan (classical Chinese). A general comparison is made in order to explore the causes, modifications and strategies of the generic transformation during the process of adaptation. The discussion is grounded on a contextual analysis and explores the ways in which various factors, such as linguistic evolution, generic tradition, biographical background and socio-cultural praxis worked together to shape the narrative conventions of wenyan and baihua and how the two languages interacted, especially in the popular story writing of the late Ming urban society.
Kinetics and phase behaviour of transesterification of triglycerides

Experiments were conducted to determine the optimum conditions for the transesterification of soybean oil using mixtures of methanol and ethanol. The optimum conditions found for the reaction were: (1) 50°C, (2) 9:3:1 methanol/ethanol/oil molar ratio and (3) 0.5 wt% sodium methoxide catalyst. Two-phase base-catalyzed transesterification of vegetable oils is the most common method for making commercial biodiesel. During the transesterification, phase changes occur, which significantly affect the kinetics and steady state positions of the reaction. In addition, a new workup procedure was developed, in which oxalic acid in methanol was used to quench transesterification reactions. This avoided hydrolysis and converted all soap back to fatty acids. The removal of catalyst by the glycerol-rich phase, rapidly decelerated the reaction. At the beginning of the reaction the triglyceride, which entered the methanol phase was rapidly converted via diglyceride and monoglyceride to ester. Some triglyceride did not enter this methanol phase before the reaction decelerated, resulting in abnormally high level of triglyceride in the product. Glycerol separation also slowed down the soap formation in the biodiesel-rich phase, and removed the resulting soap into the glycerol-rich phase. Once the glycerol separated, mixing was required to re-suspend it and facilitate transfer of catalyst back to the ester phase. A polar dye was used to "visualize" phase behaviours in methanolysis, ethanolysis and butanolysis of soybean oil using a 6:1 alcohol oil molar ratio, 1.0 wt% catalyst (with respect to the oil) at ambient temperature. Methanolysis and ethanolysis reactions commenced as two phases (alcohol and oil), then formed emulsions and ended as two phases as glycerol byproduct separated. Butanolysis remained monophasic throughout. Ethanolysis was more easily initiated by mixing than was methanolysis. Ethanolysis also exhibited a much longer emulsion period and slower glycerol separation. The glycerol-rich phase was smaller in volume in ethanolysis than in methanolysis. At 23°C, for methanolysis, 42.0% of the alcohol, 2.3% of the glycerol and 5.9% of the catalyst were in the ester-rich phase at steady state. In the ethanolysis, 75.4% of the ethanol, 19.3% of the glycerol and 7.5% of the catalyst were in the ester-rich phase.
IFlow and beyond: Bandwidth-efficient and delay-aware information access in mobile ad hoc networks

Due to node mobility and limitations on bandwidth availability in wireless channels, there exist unique challenges towards achieving efficient and effective information access in wireless ad hoc networks with mobile nodes. In this thesis, we address two critical questions: (1) How may information be accessed with the highest degree of bandwidth efficiency? and (2) How should algorithms be designed so that node mobility contributes positively towards high performance and efficiency? We present iFlow, a middleware-based framework for bandwidth-efficient and delay-aware information access for mobile ad hoc applications. We present the case of information rendezvous, where the demands for information are satisfied by the supplies in a fully distributed fashion, across third-party nodes beyond information suppliers and consumers. Such rendezvous is achieved via controlled diffusion of information from the suppliers, matched by the gleaning process on the consumers. We validate our claims using simulation and experimental results.
Dynamics and vibration-suppression control of flexible-payload manipulator systems

Recently, there has been a growing interest in manipulating, transporting and positioning flexible payloads (for example, metal sheets) in various industrial applications, such as robotic assembly of automobile sheet-metal body parts. The system tackled in this thesis consists of a rigid robot manipulator and a piece of flexible sheet metal that is grasped at several points by the robot gripper. A major concern related to the performance of such a system is the vibration of the payload and its effect on the robot position. This vibration has to be eliminated before the payload can be precisely positioned for further processing on it. Thus, the main objective of this thesis is to develop an effective robot control strategy for payload vibration suppression that is practical in implementation and robust against model uncertainties. Prior to developing a control scheme, it is useful to obtain an accurate and practical dynamics model of the system. To achieve this, a new method is presented in this thesis for modeling the entire robot-payload system. Using this dynamic model, the vibration controllability issue is examined in order to configure the robot-payload system properly so that all the critical vibration modes of the payload are controllable. Explicit criteria are provided to determine the configurations that result in uncontrollable vibration, and hence these situations can be avoided at the system design stage. A feedforward/feedback control strategy is proposed in this thesis for payload vibration suppression. The feedforward loop consists of an input-preshaping technique and a computed-torque scheme. A new approach is developed for designing an input shaper. It utilizes a structure in which the modal forces of payload vibration are shaped in parallel. This approach relaxes the requirement of dynamic linearity in traditional shaper designs, and for the nonlinear robot-payload system, it improves the shaper's performance in vibration suppression. Given a precise dynamic model, the feedforward control can effectively achieve vibration-free movements of the payload. To enhance the control robustness against model uncertainties, a model-independent feedback loop is proposed, in which a robust vibration-suppression control is developed by using the reaction force of payload vibration at the robot gripper. The feedback control can accomplish further reduction of any residual vibration on the payload due to model uncertainties. This proposed control strategy is practical as it does not require direct measurement of payload vibration, and also has a simple structure with low on-line computational load. Extensive numerical simulations are presented in this thesis to validate the developed dynamic models and to illustrate the effectiveness and robustness of the vibration-suppression control strategy. Rigorous stability and performance analyses of the control strategies are also conducted.
Identification and characterization of enhancer elements in the first intron of the human proglucagon gene

The proglucagon gene is expressed in the pancreas, intestines, and brain. Tissue-specific post-translational processing of proglucagon results in the liberation of glucagon in the pancreas, and glucagon-like peptide-1 and -2 in the intestines and brain. Proglucagon-derived peptides play essential roles in human physiology. To identify sequences that may have roles in regulation of human proglucagon expression, the strategy of comparative genomics and in vitro transfection were utilized in my research. Human proglucagon genomic sequence was compared with orthologous rodent sequences. An evolutionarily conserved 483 bp region was found in intron I of the proglucagon gene. The transcriptional activity of intron I of the human proglucagon gene and that of the conserved region within intron I were tested in rodent cell lines. I demonstrated that intron I of the human proglucagon gene is an enhancer-like element, and its enhancer activity is confined within the conserved 483 bp segment. Thus, I provided a novel regulatory mechanism underlying the regulation of human proglucagon gene expression.
Gaussian Z-interference channel with a relay link: Achievability region and asymptotic sum capacity

This thesis studies various relaying strategies for two types of Gaussian Z-relay interference channels. The main results of this thesis are as follows: For the Gaussian Z-interference channel with a digital link from the clean receiver to the interfered receiver, it is shown that digital relaying is capacity achieving in the strong interference regime, and asymptotically efficient in the weak interference regime in the sense that each relay bit improves the sum capacity by one bit in the high signal-to-noise ratio and high interference-to-noise ratio limit. For the Gaussian Z-interference channel with a digital link from the interfered receiver to the clean receiver, it is shown that, in the strong interference regime, decode-and-forward strategy is capacity achieving. In the weak interference regime, an achievable rate region is derived using a quantize-and-forward strategy. However, in this regime, the sum-rate gain due to the digital link is upper bounded by half bit.
Asymptotic dynamics of trapped solitons of nonlinear Schrödinger equations with potentials

In this thesis we study dynamics of solitons in the generalized nonlinear Schrodinger equation (NLS) with an external potential in all dimensions except for 2. For a certain class of nonlinearities such an equation has solutions which are periodic in time and exponentially decaying in space, centered near different critical points of the potential. We call those solutions which are centered near the minima of the potential and which minimize energy restricted to L2 -unit sphere, trapped solitons or just solitons. In this thesis we prove, under certain conditions on the potentials and initial conditions, that trapped solitons are asymptotically stable. Moreover, if an initial condition is close to a trapped soliton then the solution looks like a moving soliton relaxing to its equilibrium position. The dynamical law of motion of the soliton (i.e. effective equations of motion for the soliton's center and momentum) is close to Newton's equation but with a dissipative term due to radiation of the energy to infinity.