Two aspects of the lead acid battery have been researched in this work. The first investigates some of the complex questions concerning the nature, composition and chemistry of lead sulphate membranes using scanning electron microscopy (SEM), impedance spectroscopy (IS) and inorganic chemistry techniques. A review of the literature on lead sulphate and precipitate impregnated membranes together with their role in the lead acid battery is presented.

This dissertation modifies error-correcting codes and Bloom filters to create high-capacity associative memories. These associative memories use principled statistical inference and are distributed as no single component contains enough information to complete the task by itself, yet the components can collectively solve the task by passing information to each other. These associative memories are also robust to hardware failure as their distributed nature ensures there is no single point of failure. This dissertation starts by simplifying a Bloom filter so that it tolerates hardware failure (albeit with reduced performance). An efficient associative memory is created by performing inference over the set of items stored in the Bloom filter. This architecture suggests a modification which forgets old patterns stored in the associative memory (known as a palimpsest memory). It is shown that overwriting old patterns in an independent manner reduces performance, but is still comparable to the well-known Hopfield network. The lost performance can be regained using integer storage which allows the superposition of the pattern representation, or ensuring bits are not overwritten independently using concepts from errorcorrecting codes. The final task performs recall in continuous time using components which are more similar to neurons than used in the rest of the dissertation. The resulting memory has the exciting ability to recall many patterns simultaneously. Statistical inference ensures gradual degradation of the performance as an associative memory is overloaded. Since many definitions of associative memory capacity rely on the existence of catastrophic failure a new definition of capacity is provided. In spite of some biologically unrealistic attributes, this work is relevant to the understanding of the brain as it provides high performance solutions to the associative memory task which is known to be relevant to the brain.

Data is an important resource of an organization and is one of the fundamental building blocks of an effective information system. The failure of top-level management to define a framework for information systems and to recognise the potential of the data resource has a serious impact on information systems costs and development. This thesis attempts to identify some of the problem areas associated with unmanaged data and proposes a framework for the design of a Data Administration and Control System (DACS). Existing data analysis techniques have been reviewed and were found to be inadequate to meet the general requirements for data definition and documentation. DACS, when implemented, will assist in the identification and definition of the data resource, how it is used and where it is stored throughout the organization. It provides a tool to monitor and control the data and to assist in the design of information systems. DACS has applicability in the growing field of computer-aided information systems analysis and design. DACS itself is an automated approach to the definition of data and its uses. Extensions to the basic design are discussed which would further contribute to the development of computer-aided design tools. / Business, Sauder School of / Graduate

The objective of this thesis is to develop and define the concept of a total management information system. The term "total system" has been grossly misrepresented since its coinage, however, the misuse can be attributed to ignorance of its full meaning. The misuse is also attributed to narrow thinking on behalf of the user for its application has mainly been directed to a specific circumstance. The study defines the term "total management information system" and it also outlines the attributes which make up the total system. As in all situations where an ideal is created, there is resistence to reaching the ideal - these barriers are enumerated and commented upon. To test the validity of the concept, it is applied to an existing company's informational system by the methodology of a systems analysis. Conclusions are reached on the soundness of the concept and on the status of the case company toward its claim of holding the totality status. Primary research was conducted on the theory of a total system; secondary research was conducted into the existing systems of the case company. Throughout the study, observations were made concerning the problems associated with the topic and an evaluation is made on the status of the evolution of the total information system. / Business, Sauder School of / Graduate

This thesis describes the properties of a memory in which locations are software addressed using a tree. The properties investigated were chiefly concerned with the practical issues of memory usage and access time. Investigations of these properties were made by using statistically different inputs to a computer model of the memory. The most probable tree structure for one type of input was calculated. It is concluded that the software tree, with uniform distribution input requires more memory capacity than a normal storage scheme. On the other hand, the access time can be much reduced. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

This research presents the development of a transmittance- absorptance parameter for a solar pond. Such a parameter represents, directly, the fraction of the incident solar radiation which is absorbed at the bottom of the solar pond. It can be used to represent pond performance through an equation analogous to the Hottel-Whillier-Bliss Equation for a flat-plate solar collector. The above parameter is called the transmittance - absorptance product and is an energy-weighted quantity. Monthly values of the proposed parameter are developed from an hour-by-hour simulation. The simulation utilizes hourly values of spectral solar radiation reaching the earth's surface which are computed from a state-of-the-art algorithm that has been slightly modified to better estimate diffuse spectral radiation at large solar zenith angles; the modification is also presented. Thermal conductive losses through the water layers and the surrounding earth together with evaporative and convective losses are usually the only loss mechanisms considered for a solar pond. Under clear skies and to a lesser extent under cloudy skies, a longwave radiation heat loss also occurs from the pond surface. The estimation of radiative loss from any terrestrial surface requires detailed computations and atmospheric data. The procedure has been greatly simplified through a correlation which yields spectral atmospheric emissivity from the amounts of absorbing gases present in the atmosphere. It is recommended for further study that the performance of a solar pond be estimated using the proposed transmittance-absorptance product to compute the solar energy absorbed in the pond, and that the longwave radiative loss from the pond be included in the analysis. A comparison with data obtained from an existing solar pond is recommended to validate the results obtained in this study. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

With the growing use of computers as tools for the automation of clerical tasks, there has come not only a proliferation of documentation, but the realization that computers could be employed in automating certain aspects of the production of documents — not only such documents as describe computer developments, but also papers, briefs, letters, etc. The runoff program, usually an adjunct to a text editing facility, has been in existence for a long time, but its use has been limited to computing installations and those directly involved with computing. The reason for this is two-fold: public unawareness, and the ad hoc nature of runoff program design have prevented wider use. This thesis is an attempt to present a reasoned design of a program which acts enough like a rather intelligent typewriter to be usable by members of the public, but gives the user with a greater computing background enough power of expression in terms of programming language and layout design, to overcome some of the limitations of earlier runoff programs. Previous work in the area of text processing which relates to document processing is examined in some detail. The underlying ideas common to existing document-processing facilities are brought forth, and examined in the light of what a user might reasonably expect of such a facility. The resulting design for a document processor is presented in an orderly fashion, outlining the reasons for design decisions and backing away respectfully from designs which are unfeasible for economic implementation. An entire chapter is devoted to a description of the resulting document processor, in the form of a somewhat rarified user's manual. Suggestions for and details of an implementation are given, based on the author's own experiences with implementation. A bibliography and a short glossary of the most important terms and those most likely to confuse are appended to the thesis. / Science, Faculty of / Computer Science, Department of / Graduate

The advantages of an optical spatial phase filter constructed by thickness variations are put forward and a method of fabricating such a device using vacuum deposition techniques is detailed. The design and construction of a vacuum system to produce such a device is outlined. The system comprises a vacuum chamber with a source holder for zinc sulfide, an electronically controlled shutter, an aperture, and a substrate and holder mounted on an x-y motion table driven by stepper motors. The system is controlled by a minicomputer and measurements of thickness are made by an ellipsometer controlled by the minicomputer. Experiments conducted with the system determine the spatial resolution and closed loop control capabilities to be adequate. An analysis of the results of the tests concludes that with further refinements it seems feasible to fabricate spatial phase filters by using vacuum deposition techniques. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

This thesis identifies and discusses physical mechanisms in intercalation batteries. The effects of interactions and ordering of intercalated atoms on the voltage behaviour of intercalation cells is described, largely in terms of the lattice gas model of intercalation. Particular emphasis is given to the mean field solutions of the lattice gas model, which are compared to more exact solutions for several cases. Two types of interaction between intercalated atoms are discussed, namely electronic and elastic interactions; it is found that both can be important in intercalation compounds. The kinetics of intercalation batteries is also discussed, with emphasis on overpotentials due to diffusion of the intercalated atoms in the host lattice. Experimental studies of the voltage behaviour of three types of lithium intercalation cells, Li[sub=x]TiS₂, Li[sub=x]MoO₂, and Li[sub=x]MoS₂, are presented, which illustrate the variety of voltage behaviour found in intercalation cells. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

On May 11th, 2019, atmospheric CO2 levels reached 415 ppm, a number 40% higher than the maximum level ever reached in the 800 000 years prior to the Industrial Revolution. This rise can be directly attributed to human activity, and has been linked to global temperature increase and climate change. Net CO2 emissions continue to rise as economies grow, and in 2018 global emissions reached 37.1 Gt. In order to reach the climate targets identified in the 2015 Paris Agreement, some scientists estimate that the world will need to attain net-zero anthropogenic greenhouse gas (GHG) emissions by 2050. Achieving this goal will require deployment of multiple technologies across multiple sectors. Of particular importance will be reducing or eliminating emissions associated to energy production via combustion of fossil fuels, which account for over 80% of CO2 emissions in G20 countries. One method of achieving this is to displace fossil fuel electricity generation with renewable source generation. Canada currently has 12 GW of installed wind capacity, and although it is the country’s fastest-growing source of renewable electricity, widespread deployment is inhibited by technical challenges including the time variability and geographic dispersion of sources. A potential solution to overcome the challenges facing integration of renewables is grid-scale energy storage. Many storage technologies currently exist at various levels of maturity. Although currently low on the development scale, thermochemical energy storage (TCES) has gained significant interest due to its potential to offer low-cost, short- or long-term storage of high-temperature heat using non-toxic, abundant materials. Several recent works have focused on the potential to pair the calcium looping (CaL) process, which exploits the reversible calcination of calcium carbonate, with concentrated solar power (CSP). This would enable CSP to provide continuous power to the grid while receiving discontinuous solar input, and recent projects have predicted storage cycle efficiencies in the range of 38-46%. As an extension of the work done to date, this project proposes a novel configuration of the CSP-CaL process which may offer advantages over other proposed configurations, including a reduction in process equipment requirements, elimination of pressure differentials between vessels, and a reduction in compression duty during the energy discharge period. A process simulation of the proposed system shows that it is capable of offering comparable storage cycle efficiencies, with the overall efficiency being strongly dependent on the residual conversion of calcium oxide in the carbonator as well as on the efficiencies of the power cycles employed to discharge the stored energy. In addition to the technical challenges that may come with this type of system, social and economic barriers may arise due to the fact that it will require large-scale storage of CO2, mining of natural limestone, and potentially large and complex facilities. All of these challenges must be considered and addressed in order to achieve deployment of this technology within Canada and around the world.