This thesis describes the study of plate vortex ring generators invented and developed by Latta and modified and constructed by E.S.Fox. The vortex ring generator has been applied to destratify and aerate a natural pond in this research. Experiments were conducted to mix and aerate a stagnant and stratified pond in a natural, outdoor setting. Mixing times, temperatures, dissolved oxygen, BO...

Part A: No abstract provided. Part B: A method for measuring the complex permittivity of insulator materials at microwave frequencies is described in detail. Results of dielectric measurements using this technique are in good agreement with data from other sources. MKS units are used in this report.

The realm of the nano-world begins when things start getting smaller in size than one thousandth of the thickness of the human hair. Surface patterning at the nanoscale has started to find applications in information storage, self-cleaning of surfaces due to the "lotus effect", biocompatible materials based on surface roughness and many more. Several methods such as particle-beam writing, optic...

The Volta River Authority (VRA) is responsible for the generation and transmission of power in Ghana. For this purpose, VRA owns and operates two hydroelectric generating stations (at Akosombo and Kpong) with a combined installed capacity of 1060 Kw. The Akosombo plant is served by the Lake Volta Reservoir. Prediction of inflows into the Volta Lake is one of the important functions of...

The main body of this thesis deals with three related concepts pertaining to vaccination strategies for childhood infectious disease. Chapter 2 deals with the implications of reversion in the Oral Polio Vaccine on global polio eradication programs. Chapter 3 explores the phenomenon of contact or secondary vaccination in the use of live-attenuated virus vaccines. Chapter 4 explores the i...

Credit risk is the risk of losses due to the failure to fulfil the obliged payment from a debtor or a counterparty. It is one of the three major components of risks that a bank faces as defined in the new Basel Accord. The credit risk literature has experienced similar rapid growth as the credit market itself. There are currently four different approaches to analyzing credit risk: structural...

Ore specimens from the cupriferous zone of the basal Nonesuch shale at the White Pine Mine were analysed for sulphur isotopes, carbon and sulphide contents and boron. The results of the analyses were discussed in relation to a biogenic-syngenetic mineralization process for the ore body. A model, based on the δS³⁴sulphide frequency distribution, was developed to determine the δS³⁴ sulphate value...

This study combines longitudinal and cohort analyses to provide an extensive examination of the nature of postsecondary stratification among Canadian and American universities and students in this era of unprecedented postsecondary expansion, institutional diversification, and rising competition for external research funding. Multiple statistical methods and a range of data sources are emplo...

In this investigation the methods of obtaining uniform and maximum germination of seeds and of producing contamination-free cultures of the shoot apices of Pharbitis nil have been examined and established.

Flowering response of vegetative seedlings of different ages has been investigated as related to photoperiodic induction. The sequence of orphological changes at the shoot apex h...

Because of the importance of undecidability and the concern with the high complexity of automated reasoning, a few interval-based temporal description logics (ITDLs) have been designed. Moreover, most existing ITDLs are not able to specify the lengths of intervals. In other words, they are not metric. On the other hand, some domains (e.g., medicine) are inherently interval-based, and require a ...

The McMaster Intense Positron Beam Facility (MIPBF) is a project based on the McMaster Nuclear Reactor (MNR) that aims to set up the first intense positron beam in Canada. The final intensity of the moderated positron flux is expected to be 109/s, which will make the positron beam one of the most intense ones in the world. A general review of intense beams, including the linac-based positron be...

Multiple studies have implicated the POZ-ZF and methyl-DNA-binding transcription factor, Kaiso, in the regulation of genes and pathways that are important for development and tumorigenesis. In Xenopus embryos and mammalian cultured cells, Kaiso has been implicated as a negative regulator of the canonical Wnt signaling pathway. Paradoxically however, Kaiso depletion extends lifespan and delays p...

Vibration analysis (VA) is an extremely valuable technology which has been around for decades but its application and deployment techniques continue to grow. In 2006 W.S. Tyler, an industrial screening company, approached the McMaster Computing and Software department in search of a VA strategy to be used in their industry. The massive screens they produce vibrate with incredible speed and forc...

This thesis provides a reading of Anita Rau Badami’s novels The Hero’s Walk and Can You Hear the Nightbird Call? The interpretive frame constructs a theory of affect to explore the human experience of beauty through a reading of Badami’s texts. This work’s approach to beauty is derived largely from Elaine Scarry’s On Beauty and Being Just and from musings on beauty by Simone Weil. Following Wei...

Seismic response of free standing un-anchored objects is required to be studied in Nuclear Power Plants (NPPs) for their own integrity and potential interaction with the surrounding seismically qualified safety systems. Rocking response of a rigid body subject to seismic excitation is not very well covered in the nuclear standards except for an approximate method given in ASCE 43-05 where the d...

The realization of inductorless filters by means of RC-gyrator structures has been investigated, and the sensitivity of their response characteristics with respect to supply voltage variations has been measured. A critical appraisal is made of the various multiparameter sensitivity functions which have already been proposed in the literature, and the methods by which these sensitivity crit...

My dissertation is composed of an introductory chapter followed by three independent chapters focusing on two themes: health and retirement. The last chapter concludes. After the introductory chapter, the second chapter investigates whether self reported general stress is a mediator in the relationship between socio-economic status (SES) and health. I use a six-year long panel of the Canadian ...

The activity-based approach to the study of travel behavior implies a shift in focus from discrete trips to activities. A fundamental tenet of this approach is that individuals, when making their own activity-travel decisions, tend to interact with other members within a household. However, most activity-based research to date has been conducted at the individual level, but not at the household...

Good nutrition is essential to aging well. Much of the malnutrition that occurs in long-term care is preventable, attributed to the eating environment, food quality and the ability to access food. Join Heather Keller, a leader in research on nutrition and aging, as she shares her views on these issues and how we can provide a better foundation to healthy aging.