title: The State and Social Policy Outcomes

contributor:
Dear, M.J.
Geography

subject: Geography Geography

abstract: This study is concerned with analysing the effect of the state in influencing policy outcomes within the field of mental health care. An historical-hermeneutic approach is adopted and this require a theoretical investigation of the state and its apparatuses in capitalism; an historical review of mental health care; the formulation of propositions to be tested; and the empirical investigation of the propositions. Trends within mental health care are examined over the period 1960-1979 using the Hamilton Psychiatric Hospital as a sample of the trends in Ontario. A Cochrane-Orcutt least squares regression model is used to link these trends to indicators of the propositions. Supplementary descriptive data are also examined to incorporate trends outside the hospital. The results reveal the importance of the current fiscal crisis of the state in influencing mental health care policy outcomes. An increasing number of state apparatuses, including the mental health professionals and their ideologies, are required to legitimate the deinstitutionalization policy, which aims more to avert the fiscal crisis of the state than to benefit the health of mentally ill patients.

abstract: Master of Arts (MA)


title: The Formation of the Asylum in Upper Canada

contributor:
Bell, N.
Sociology

subject: Sociology Sociology

abstract:
The purpose of this dissertation is to develop an explanation for the formation of a lunatic asylum in early nineteenth century Upper Canada. In order to understand the separate institutionalization of the mad in lunatic asylums, I examine the asylum within the context of the transformations in social life in the late eighteenth and early nineteenth centuries.

The dissertation addresses the question: Why in the period 1841-53 did the Upper Canadian State provide for the separate institutionalization of the mad in asylums? This question has led to the investigation of events and social processes prior to the establishment of the Toronto Lunatic Asylum which determined its formation. In order to understand the event of asylum formation. I have introduced a holistic explanation based in the general principles of Marxist political economy.

Embedded within an explanation of asylum formation in Upper Canada is not only the social structure of Upper Canadian Society but also the history of the confinement of the mad prior to asylums. The latter covers the confinement of the mad within the institutions of public welfare and their association with poverty. Since Upper Canada was a colony of Great Britain, its organization was closely tied to Britain. Their histories are intertwined and their methods of incarceration similar.

This dissertation illustrates the point at which the inasne were pushed out of the institutions of public welfare and into the hands of the medical profession. Asylum formation is an event that marks the end of one era of treatment or the mad and the birth of another. It is an event which begins the process of separating the mad from the poor and associating the mad with the sick, a process which, in its institutional form, took over a century to complete.

abstract: Doctor of Philosophy (PhD)


title: Chemical Investigations Relating to the Field of Platinum Anticancer Drug Research

contributor:
Lock, C.J.L.
Chemistry

subject: Chemistry Chemistry

abstract:
Research relating to platinum anticancer drugs follows two schools of thought. One school strives to unravel the mystery surrounding the mechanism of action of these drugs and the second concentrates on developing new platinum drugs superior to those currently available. The work to be discussed relates to both approaches.

The chemistry and structural features of model diammine-dinucleobaseplatinum(II) complexes will be examined and predictions made as to the effects such lesions may have on DNA. In addition, the synthesis and chemicaI characterizations of new pIatinum complexes will be discussed and when possibIe predictions made as to their potential as anticancer agents. The importance of complete and reliable chemical characterizations of these species and others relating to this field will be emphasized.

abstract: Doctor of Philosophy (PhD)


title: The predictability of invasive cervical neoplasia by the presence of specific human papillomavirus sequences in preinvasive cervical neoplasia

contributor:
Rawls, William E.
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract:
Cancer of the cervix is the second most common form of cancer in women worldwide. The natural history of cervical cancer is thought to involve sequential changes from varying grades of precursor intraepithelial lesions called CIN. However, little is known of the risk factors that can predict the oncogenic potential of a particular CIN lesion. Based on their preferential occurrence in cervical cancers and their potential oncogenic properties, the human papillomaviruses (HPV) particularly the genotypes 16, 18, 31, 33, 35 and 42 have been implicated in the etiology of invasive cervical cancer. However, these viruses could occur as either secondary pathogen of cancer or as predictor of those CIN lesions that are likely to progress to invasive disease. The hypothesis that was verified in this study was that HPV 16,33 and 18 are likely to be predictive of CIN lesions that progress to invasive cancer.

First of all, in order to characterize the prevalent type of HPV in the target study population of B.C., a cross-sectional study was conducted and the presence of specific HPV types ascertained by the tissue in situ hybridization. The frequency of HPV types 16, or 33, was found to vary with the severity of the CIN grades, in contrast to the frequency of HPV types 6/11 and 18 that segregated independently of the CIN grades.

Next, a case-control study was undertaken to verify the main hypothesis of HPV being predictive of CIN lesion progression to invasion. It was reasoned that the particular HPV would occur at higher frequency in CIN biopsies of cervical cancer cases than in CIN biopsies of noncases (controls). A total of 47 cases and 94 controls were enrolled from patients registered by the Cancer Control Agency of the Province of British Columbia. A case was defined as a post-pubertal woman with invasive disease and who had a CIN diagnosis at least two years prior to the invasive disease. For each case an attempt was made to enrol two control matched on grade of CIN and year of diagnosis. On each subject attempt was made to gather demographic informations that are known to be associated with cervical cancer. The HPV probes that were used included HPV 16/33 and HPV 6/11. The relative frequency of occurrence of specific HPV in the preinvasive biopsies of cases and controls were as folow: HPV 16/33 occurred in 10.6% of controls and 12.8% of cases; HPV 18 was found in 3.2% of controls and 8.7% of cases and HPV 6/11 in 2.2% of controls and 8.7% of cases. Conditional Chi-square analysis showed that the difference in the proportions of HPV positivity between cases and controls was compatible with sampling variation. Hence, with a statistical power approximately 60%, it was concluded that particular HPV could not be predictive of CIN lesions progression in the sample of population that was studied.

However an excess risk for incurring cervical cancer, by being exposed to particular HPV at the CIN stage, was noted. The relative risk for HPV 16/33 was 2.34, [95% CI 0.70 to 7.66]; for HPV 18 was 2.45, [95% CI 0.22 to 27.80]; for HPV 6/11 2.19, [95% CI 0.39 to 12.42] or for all HPV combined was 1.87, [95% CI 0.55 to 6.28].

Interestingly, a comparison of the frequency of HPV occurrences in the case-control study with that in the cross-sectional study revealed a lower rate of HPV positivity in the case-control component. This could possibly be due to a cohort effect.

abstract: Doctor of Philosophy (PhD)


title: Inhibition of Gastric Emptying is Neither Necessary Nor Sufficient for Peptide Induced Safety in the Rat

contributor:
Weingarten, H.P.
Psychology

subject: Psychology Psychology

abstract:
This research examines the hypothesis that the satiety effect of cholecystokinin octapeptide (CCK-8) is mediated by changes in emptying. A method for collection of gastric emptying data, the double sampling procedure, is developed and validated for use in the rat. The double sampling technique permits repeated measurements of liquid gastric volume and thus describes the time course of emptying within a single experimental session. Further, the method allows determination of the amount of gastric secretion, volume emptied into the intestines, and amount of gastric load remaining in the stomach. Experiments are presented which: i) demonstrate the utility of the technique; ii) validate its accuracy in determining gastric volume; iii) indicate the stability of measurements obtained with this procedure; and iv) provide a procedure for quantitative evaluation of data obtained with this technique.

Using the double sampling procedure, the ability of CCK-8 to delay gastric emptying and to influence feeding are then compared under similar experimental conditions. The effect of CCK-8 on gastric emptying is assessed in 6 hr deprived rats receiving 10 ml intragastric test loads of either .15M saline or 15% sucrose. Intraperitoneal (ip) injections of CCK-8 in doses of 1.4-22.4 ug/kg produce a dose-dependent retardation of gastric emptying of both saline and nutrient. Lower doses of CCK-8, 0.01.and 0.1 ug/kg, have no effect on gastric emptying.

The effect of CCK-8 on feeding is assessed in rats tested under the same experimental conditions used in the gastric emptying studies. Doses of CCK-8 capable of retarding gastric emptying also suppress eating in a dose-dependent manner. These findings provide necessary correlational support for the hypothesis that satiety produced by CCK-8 is mediated by inhibition of gastric emptying. However, a further quantitative analysis of the correspondence of the gastric emptying and feeding effects of CCK-8 suggest that retardation of emptying may not account for the entire satiety effect of the peptide.

The next set of studies provide direct tests of whether changes in gastric emptying mediate CCK-induced satiety. If gastric emptying plays a significant role in the satiety produced by CCK-8 then: i) the effects of CCK-8 on emptying and feeding should share similar kinetics, and ii) peptides that inhibit emptying should also inhibit feeding. I show that CCK-8 (5.6 ug/kg) injected coincident with introduction of an intragastric load or presentation of a test meal produces a rapid inhibition of both emptying and feeding.

In contrast, the identical dose of CCK-8 administered 15 min before testing causes no inhibition of emptying, even though the peptide retains its ability to produce satiety. I also test the abilities of the peptides pentagastrin (100 ug/kg), bombesin (8 & 16 ug/kg) and secretin (2.86, 14.3 & 28.6 ug/kg) to reduce food intake and inhibit gastric emptying. Pentagastrin does not affect food intake or gastric emptying. Bombesin causes a small transient delay in emptying but a large and sustained suppression of eating. High dose secretin (14.3 ug/kg) causes no significant reduction of food intake, even though this dose of secretin inhibits emptying to the same degree as 1.4 ug/kg CCK-8, which does reduce intake. Thus, although CCK-8 does influence the rate of gastric emptying, the present results indicate that the inhibition of emptying by CCK is neither necessary nor sufficient to explain its satiety effect.

abstract: Doctor of Philosophy (PhD)


title: Structural and Physical Properties of the Vacancy Doped Systems, R₍₁₋ᵪ₎TiO₃ (R=Nd for 0.00≤x≤.33 and Sm for 0.00≤x≤0.17): An Investigation of Metal-Insulator Transitions

contributor:
Greedan, John E.
Chemistry

subject: Chemistry Chemistry

abstract: Members of the solid solutions, R₍₁₋ᵪ₎TiO₃ (R=Nd, Sm) have been prepared for 0.00≤x≤0.33 and 0.00≤x≤0.17 for R=Nd and Sm respectively. Three structural types have been identified for the R=Nd system: Pnma (0.00≤x≤0.17), Pban (0.25≤x≤0.30) and P4/mmm (x=0.33). For the R=Sm system, only the Pnma structure type has been identified by x-ray powder diffraction. D.c. susceptibility measurements reveal canted antiferromagnetic behaviour for the nominal x= 0.00 and 0.05 compositions in both systems. The observed Neel temperatures are 100K and 75K respectively for x=0.00 and 0.05 in the Nd₍₁₋ᵪ₎TiO₃ system and 50K and 42K for the x= 0.00 and 0.05 compositions in the Sm₍₁₋ᵪ₎TiO₃ system. The magnetic structures of these phases have been determined using neutron diffraction methods. Paramagnetic behaviour is observed for x≥0.10 in both systems. Four probe van der Pauw measurements reveal two metal-insulator transitions in the Nd₍₁₋ᵪ₎TiO₃ system at x= 0.10 and x=0.25 and only one for the Sm₍₁₋ᵪ₎TiO₃ system at x=0.10. In the metallic regime, the resistivity behaviour indicates these compounds are poor metals with highly correlated behaviour possibly associated with the Kondo effect and Fermi liquid character. Further investigation of these "metallic" phases by specific heat measurements reveal a divergence of the carrier mass as the Mott transition is approached from the itinerant side in accordance with the Brinkmann-Rice model. Thermopower measurements in both systems reveal the presence of p-type conduction in the Mott insulator phases, while n-type conduction is observed for x ≥ 0.10. The thermopower behaviour of the "metallic" phases can be described using Mott's law for metals.

abstract: Doctor of Philosophy (PhD)


title: The Interaction of Rat Transferrin with the Liver with Special Reference to the Glycan of Transferrin

contributor:
Regoeczi, E.
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract:
Rat transferrin (RTf) was used to study the interaction of transferrin' (Tf) with the liver, with special reference to the çlycan of Tf.

Iron uptake from Tf by cells is believed to occur by Tf receptor (TfR)-mediated endocytosis. Results from the present studies revealed that over a large range of competing diferric RTf concentrations, a constant percentage of iron is uptaken from RTf by the liver in vivo, and by hepatocytes in vitro. Hepatocytes were found to contain ~129,000 TfR/cell with ~40% expressed on the surface as estimated by both a polyclonal anti-TfR antiserum, produced as part of this thesis work, and a monoclonal anti-TfR antibody. On the basis of this estimate it was calculated that TfRs are not present in sufficient quantities to account for the observed uptake of iron. Studies of uptake and release of polyvinyl-pyrrolidone (PVP), RTf, and iron (as diferric Tf) were carried out in suspended hepatocytes. These studies demonstrated that the most likely mechanism to account for the results and to explain the iron uptake is "mixed-type" pinocytosis. The uptake of iron was found to be modulated by the type of glycan on RTf.

On the basis of glycan microheterogeneity, at least six subforms of RTf are found to exist in rat plasma. These subforms are RTf-1, RTf-2·and RTf-3 as resolved by concanavalin A; ~20% of each is fucosylated and ~80% non-fucosylated. (The presence of fucose was found to have no measurable effect on catabolic rate, plasma iron disappearance or iron donation to liver in vivo or hepatocytes in vitro.) The slalylated subforms have different half-lives (RTf-1>RTf-2>RTf-3) with RTf-1 being significantly longer than RTf-3. Comparison of plasma iron disappearance and rates of iron donation to liver in suggested a trend (RTf-l>RTf-3>RTf-2) which was reproduced and found to be significant in studies with hepatocytes: iron uptake by hepatocytes from RTf-1 and RTf-3 could be competitively inhibited by an excess of the homologous subform. Desialylation of the subforms (RAsTfs) significantly reduced the half-lives and altered the order (RAsTf-3>RAsTf-1>RAsTf-2) with RAsTf-3 being significantly longer than RAsTf-2. The desialylated subforms were superior donors of iron to the liver in vivo. Studies to explain the enhanced rate of iron delivery by RAsTf, discounted the possibility of differing rates of iron release, but allowed postulation of a synergistic dual receptor mechanism. Results from experiments with hepatocytes in vitro supported the proposed mechanism. It is concluded that subtle differences in glycan structure can result in functional differences between Tf subforms.

abstract: Doctor of Philosophy (PhD)


title: Solution Properties Photochemistry and Photophysics of Poly(N-Isopropylacrylamide) and Its Copolymers

contributor:
Guillet, J.E.
Chemistry

subject: Chemistry Chemistry

abstract:
The main objective of this thesis was to compare and contrast the behaviour of poly(N-isopropylacrylamide) (poly(NIPAM)) and its copolymers in organic solvents with their behaviour in water. Three fields of investigation were chosen: solution properties, photochemistry, and photophysics.

The experimental observations were based on a very careful examination of the reliability of the techniques of osmometry and viscosity. These techniques were used to determine the solution properties and the quantum yields of chain scission of copolymers of NIPAM with methyl vinyl ketone and methyl isopropenyl ketone. The possibility of determining the coefficients K and a in Mark-Houwink equation ([ƞ] = K Mª, in which [ƞ] is the intrinsic viscosity and M is the molecular weight of a polymer) for flexible polymers by a one-point technique, i.e., the determination of the intrinsic viscosity of one known molecular weight, was investigated using polystyrene and poly-(methyl methacrylate). The technique was applied to the studies of poly(NIPAM) in chloroform. A correlation between the Mark-Houwink coefficients K and a for rigid polymers was used for assessing the plausibility of the Mark-Houwink coefficients of some rigid carbazole containing methacrylate polymers.

The structure and sequence distribution of the different copolymers of NIPAM were also determined from the reactivity ratios. This latter study was necessary in order to determine the suitability of the copolymers for the photochemical and photophysical studies. The first studies were done in solutions and in solid films on the ketone copolymers and the second ones involved both steady state and transient fluorescent studies on copolymers of NIPAM with 1-naphthylmethyl methacrylate and 1-naphthyl methacrylate.

The studies on solution properties gave evidence of chain aggregation of the poly(NIPAM) in water. Furthermore, the stiffness parameter for poly(NIPAM) was found to be much larger than the ones of polystyrene and poly(methyl methacrylate). This stiffness increase was partially attributed to hydrogen bonding between water and the NIPAM chain.

The technique of viscosity was found to be reliable in the determination of scission numbers and solution properties if ultraviolet degradation was used as a way to obtain polymer fractions of known dispersity. This reliability was attributed to the facts that (1) chain scissions were obtained from the relative variation of molecule weight with the time of irradiation, (2) K and a are interdependent, and (3) the correction for heterogeneity was small and the activity of the degraded sample solutions, which were used for the solution properties determination, was constant.

The photochemistry of the ketone-NIPAM copolymers revealed an increase in quantum yield of chain scission (ɸcs) in water compared to dioxane and no variation of ɸcs in water with copolymer composition. The higher ɸcs in water was attributed to stabilization by water of an intermediate in the scission mechanism. This effect is in accord with the effects of polarity and hydrogen bonding in small molecule ketones. Other possibilities are discussed.

In films, the same copolymers showed a decrease of ɸcs as compared to the solution system. This was attributed to the restriction of chain mobility as the work was done below the glass transition temperature. Nevertheless, at this temperature, the quantum yield of carbonyl loss in films was still very important.

Different models for interpretation of excimer kinetics in copolymers were applied without success to a series of poly(NIPAM-1-NMA) copolymers in dichloromethane.

The photophysics of the naphthalene containing NIPAM copolymers showed that excimer formation in copolymers and their decay parameters were highly dependent on the solvent used for the experiment. A simplified kinetic mechanism was proposed in order to explain this solvent dependence. The decay parameters of the naphthalene copolymers were determined under different experimental conditions and for samples of different molecular weights and different contents of chromophores. There was concentration dependence of the parameters in water. This behaviour suggests intermolecular effects in water even at low chromophore concentration.

For the first time, it was systematically shown that photochemical and photophysical studies in water on chromophores not soluble in this medium were possible if these chromophores were attached to a water-soluble polymer.

abstract: Doctor of Philosophy (PhD)


title: Geochemical Characterization of Coastal Precipitation: Natural versus Anthropogenic Sources

contributor:
Kramer, J.R.
Schwarcz, H.P.
Geology

subject: Geology Geology

abstract:
Chemical, isotopic and air mass back trajectory analyses were combined with statistics on 39 coastal rain events at Shelburne, Nova Scotia to obtain specific information on the sources of sulphate in precipitation at remote sites.

δ ³⁴S (SO₄) was found to be highly correlated with the measured sea spray component. δ ¹⁶O (SO₄) did not correlate with sea spray and only related to δ ¹⁶O (H₂O) on a seasonally weighted basis.

The chemistry of a particular rain event was related to the provenance of its corresponding air mass as determined from the back trajectory; particularly the marine versus continental character. In some cases the air masses were vertically homogeneous and the sulphate well-mixed. In other cases, considerable vertical shearing of the air mass was observed and the sulphate appeared to have been derived from a specifIc pressure level.

Seasonal variations were observed in much of the data. Percent sea spray values were higher in the winter than in the summer as were δ ³⁴S (SO₄). Air mass back trajectories supported a different origin for summer versus winter excess sulphate. δ ¹⁶O and δ ³⁴S (SO₄)* (where * indicates excess sulphate, that is, due to sources other than sea spray) were lower in the winter than in the summer as was δ ¹⁶O (H₂O).

Most variables were separated into "marine" and "continental" indicators using factor analysis. Only the oxygen isotope data could not be included in either of these groups due to a mixture of controlling mechanisms.

In general, the Shelburne rain samples are described by a two endmember mixing model consisting of the continent and the ocean. The continental endmember has a sulphur isotopic composition of approximately 4 ‰ and represents a steady-state value for the reservoir of continental atmospheric sulphate influenced by both anthropogenic and natural contributions.

Under certain circumstances, more specific sources can be identified. Two subsets of the data are of special importance in this regard. The first is a group of samples whose air masses recently centred over the Bay of Fundy. The σ ³⁴S (SO₄)* values averaged 3 ‰ and the σ ¹⁶O (SO₄)* are correlated to their corresponding δ ¹⁶O (H₂O) values. These represent locally formed sulphate and are probably derived from oxidation of reduced sulphur gases commonly released from tidal areas. The other subset is a group of seven samples which contain a sulphate component comprising between 16 and 36% of the total sulphate which has a suIphur isotopic composition near 20 ‰ and an oxygen composition ranging from -2 to 5 ‰. It is suggested that this component represents a contribution by dimethyl sulphide (DMS) to the sulphate of Shelburne rainwater derived from the zone of high biological productivity nearby.

abstract: Doctor of Philosophy (PhD)


title: Optoelectronic Device Modeling Using Field Simulation Techniques

contributor:
Conn, D. R.
Electrical and Computer Engineering

subject:
Electrical and Computer Engineering
Electrical and Computer Engineering

abstract: Optoelectronic devices are important devices in optical fiber communications, optical signal processing, and optoelectronic equipment. This thesis develops new models for optoelectronic devices using electromagnetic field simulation techniques. To demonstrate this new technique, two kinds of optoelectronic devices are investigated in this thesis. Vertical cavity surface emitting laseer (VCSEL) is taken as the first research example due to the promising features in the application of fiber communications. A LiTaO₃ electro-optic (E-O) high-speed probe for external electro-optic sampling measurement is the second research example in terms of the need to develop a three-port electrical and optical model for the probe with the coplanar waveguide (CPW) test structure. A new microcavity model for VCSEL is developed in this thesis. The model is based on optical wave equations and implemented with state-space techniques to predict the characteristics of the microcavities. The model can be used to analyze microcavities in both frequency domains in terms of the material parameters and physical parameters of lasers and provides a simple and fast way to optimize cavity length, reflective mirror and material parameters. A three-dimensional discrete time-domain electromagnetic modeling method for microcavities is developed in this thesis. Finite-difference transmission like matrix (FD-TLM) method is modified to involve the distributed optical gain region into the full wave simulation. A simplified microcavity model is developed with the effective mirror derived in this thesis to replace the quarter-wave stacks, and can be used in the full wave modeling of optoelectronic integrated systems having complex inhomogeneities. The near-field and far-field distribution of VCSELs is obtained for the design of interconnections in fiber communication systems. A new dynamic equivalent circuit model for VCSEL is developed in this thesis to add to the equivalent circuit model family of lasers. To describe the laser dynamics, the microcavity model is coupled to the rate equations. A nonlinear resistance is used to represent the optical gain in the cavity. A spontaneous emission noise source is added to the equivalent circuit model to stimulate the noise process throughout the laser operation, which is favored in the system modeling. Stimulation results are compared with the direct rate equation solutions and show that the model is accurate and effective for providing the carrier, photon, optical field, output power, and frequency chirping response of the VCSEL in one simulation. The model enables the laser and its electrical driving circuit to be directly connected and analyzed in a unified manner and can be a powerful computer CAD model to be incorporated into nonlinear circuit modeling software. The model is a useful design tool because it is such a close analogue to the laser device which may be easily modified and enhanced. This thesis addresses the FD-TLM modeling of the LiTaO₃ E-O probe with coplanar waveguides (CPW) test structure with various configurations. A new system transfer function for the probe is defined to sample the signal directly on the sampling point. The full wave modeling of the probe with CPW test structure lays the foundation of the three-port electrical and optical model of LiTaO₃ probe with CPW test structure. To diagnose integrated circuits, it is desirable to measure signal waveforms on internal circuits. LiTaO₃ probe is widely used in E-O sampling due to its high sensitivity and transverse sampling configuration matched to the CPW test structure. Three-port electrical and optical model of the LiTaO₃ probe with CPW test structure is extremely important to the calibration of E-O measurement. With neural network techniques, the field based three-port model is constructed to provide necessary data for the optimum E-O measurement. The three-port has the same accuracy as the full wave modeling, but its characteristics are directly obtained from the neural network weighting parameters rather than the complicated full wave simulation. With this model, it is possible to de-embed both invasiveness and wave-form distortion in the external E-O sampling by giving the sampling configurations, which moves E-O sampling further towards the quantitative measurement.

abstract: Doctor of Philosophy (PhD)


title: The Risk Approach in Diarrhoeal Disease Intervention in Grenada, West Indies

contributor:
Taylor, S.M.
Geography

subject: Geography Geography

abstract:
The Risk Approach (RA) is promoted by the World Health Organization (WHO) as a strategy to improve equity and efficiency of resource deployment. Persons with characteristics known or thought to increase their chances of experiencing a particular morbidity are identified as being "at risk". The aim of RA is to identify such persons before they experience the morbidity and to provide interventions to either prevent it or reduce its impact. RA is especially intended for use within primary health care systems of lesser developed countries to improve the delivery of maternal/child health services.

Although much has been written about the potential of RA. its utility has yet to be established for most applications. Diarrhoea is the largest global killer of children under age five. RA has been suggested as a strategy to improve the distribution of proven effective interventions against it. This thesis is concerned with the use of RA in diarrhoeal disease interventions in Grenada, West Indies.

This thesis addresses two objectives. First, it seeks to validate preliminary findings on the use of RA in Grenada reported by Taylor et al.(1986). Second, it describes a conceptual framework for assessing the potential utility of proposed RA strategies. On the basis of both empirical and theoretical evidence RA is not recommended for use in diarrhoeal disease interventions in Grenada.

abstract: Doctor of Philosophy (PhD)


title: Elizabeth Gaskell and the English Novel Tradition

contributor:
Ferns, John
English

subject:
English Language and Literature
English Language and Literature

abstract:
Elizabeth Gaskell is almost universally considered a minor novelist; one of some charm, but of limited value and interest. Such a valuation can be made, however, only by ignoring the greatness of Gaskell's finest novel, Wives and Daughters (1866). If the culmination of a writing career marked by an increasing coherence to a tradition of the English novel initiated by Jane Austen. Wives and Daughters develops from and enlarges that tradition.

Gaskell's indebtedness to the tradition of the novel developing from Jane Austen's writings is often assumed by critics, but this indebtedness is usually only cursorily treated. However, Gaskell's development from the Austen tradition can be demonstrated by analysing the use she makes of it in the composition of her own novels.

The infIuence of the Austen tradition is pervasive but is most clearly shown in Wives and Daughters, in which Baskell explores the issues which concerned her predecessor in Mansfield Park (1814). Significantly, Wives and Daughters can be seen to have a direct influence upon the composition of George Eliot's Middlemarch (1871-72). Gaskell, by virtue of her finest novel, exists between Austen and Eliot in "the great tradition"; the Judgment of Gaskell as a minor novelist is an undervaluation.

abstract: Doctor of Philosophy (PhD)


title: Advanced Signal Processing Strategies for Search and Rescue Satellite Aided Tracking

contributor:
Carter, C.R.
Electrical Engineering

subject:
Electrical and Electronics
Electrical and Electronics

abstract:
Search and rescue satellite aided tracking (SARSAT) involves the use of satellites in low-polar orbits which relay the emergency signals of distressed vehicles to an earth station for signal analysis. A significant number of lives have been saved by using SARSAT. The program originated from the efforts of the three member countries of Canada, the United States and France who formed a joint venture with the Soviet Union in a program referred to as COSPAS/SARSAT. Since then, the United Kingdom, Norway and Sweden have joined the program and is expected that the system will be used worldwide.

In this thesis, three different models for emergency locator transmitter (ELT) signals are proposed. Some basic concepts and a theoretical analysis of the spectrum produced by these signal models are studied. The first model, the Ideal Coherent Model ELT, produces a highly idealized spectrum which does not exist in practice. The second model, the Non-Ideal Coherent Model ELT, is capable of producing a wide range of spectra which can he closely related to actual ELT signals. Mathematical analysis identifies a design problem not previously recognized and provides the basis for a new design specification which should become mandatory. The third model, the non-Coherent Model ELT, represents a class of ELT signals having very poor spectral properties. This type of ELT design should be avoided.

The performance of several different signal processors is evaluated using real ELT signals. The periodogram gives good performance for coherent ELT signals. However, the linear spectral estimation technique is not suitable for determining carrier frequency for non-coherent ELT signals. Use of a modified maximum entropy method in detecting these type of signals is demonstrated. In addition, spectrum ranking, sub-group averaging and spectrum levelling are found to benefit the spectral performance of the signal processors.

In SARSAT signal environment, it is possible to receive many simultaneous emergency beacon signals combined with interference of various types. The thesis also examines the sources or interference which enter the 121.5/243 MHz frequency bands of the SARSAT system.

abstract: Doctor of Philosophy (PhD)


title: Surface Cover and Air Mass Controls on Evaporation from a Subarctic Marsh

contributor:
Rouse, W.R.
Geography

subject: Geography Geography

abstract:
Measurements of radiation and energy balance components and leaf stomatal resistance and leaf area were conducted in a coastal marsh on James Bay during the snow-free period of 1985. Measurements were taken at three sites; a sedge covered backshore zone, a wet sedge marsh, and a wooded (deciduous shrub) beach ridge. The objective of the study was to examine atmosphere-biosphere interactions for the three surfaces, with regard to implications for changes in climate and/or surface cover. The scientific contributions to the literature made by this thesis and it's important results can be summarized into three categories; contributions to wetland microclimate Iiterature, contributions to ecological and bioclimate studies, and contributions to evaporation modelling.

In the field of wetland microclimate, the results of this thesis directly increase our understanding of the physical microclimate of subarctic marshes. Specifically, the thesis outlines the importance of the annual vegetation growth on energy partitioning and the evaporation regimes of the subarctic marsh. The results also address the controversial topic of evaporation from open water surfaces versus evaporation from vegetated surfaces. This thesis supports the view that the presence of vegetation reduces open water evaporation.

Within the field of plant ecological studies, the collection and presentation of the leaf resistance data set in this thesis can be considered to be a significant accomplishment in itself. Of particular importance are the analysis of leaf resistance of four previously untested wetland species, the comparison of resistance for wetIand woody versus herbaceous species, and the confirmation of the vapour pressure deficit response by these species.

These contributions can also be extended to the surface resistance data set, particularly the surface response to changing meteorological conditions. The Bowen ratio analysis presented here represents the first attempt to provide a physically based explanation of the relative importance of surface and meteorological controls on evaporation under variable meteorological conditions at the subarctic coast. It is concluded that while the influence of surface resistance was significant, its overaII effect on β was overwhelmed by the meteorological controls exhibited by changes in airmass.

The contribution of the thesis to evaporation modelling resides in the evaluation of the Shuttleworth and Wallace (1986) combination formula. The work presented here is quite Iikely the first field application of this theoretical approach. The model appears to be valid for aII ranges of Ieaf area and the discussion of some important model parameters is given.

Result from the study suggest that climate change (such as globaI warming from CO₂) wouId have a significant impact on the evaporation regime and, hence, the regional water balance of these wetlands. This might also result in a vegetation feed back responses. The lack of experimentation on coniferous open woodland species is cited as an important area for further study.

abstract: Doctor of Philosophy (PhD)


title: Inelastic Static and Dynamic Response of Frame Tube Structures

contributor:
Tso, Wai K.
Civil Engineering

subject:
Civil Engineering
Civil Engineering

abstract:
A study has been made for the ineslastic response of a thirty story frame tube structure subjected to static loading as well as dynamic excitation. The intent of this study was (i) to develop a simplified model for frame tube structures in order to compute both elactic and inelastic responses of such structures when subjected to lateral loadings, (ii) to identify the parameters that govern the behavior of frame tube structures, (iii) to assess the significance of the tube action on the elastic as well as inelastic responses, and (iv) to provide guidelines to estimate the structural responses when subjected to multiple components of earthquake ground motions.

The simplified model reduces the 3-D frame tube system into sets of plane frame, interconnected by 3-D beam column elements. It is shown that this model gives good accuracy for each of the static and dynamic loading cases when compared with the results based on a 3-D model. The computer time involved with the planar model is at least one third that for the 3-D model. Therefore, it is beleived that the proposed model is a viable tool for the inelastic analysis of frame tube structures.

The tube action if referred to as the forces developed in the two frames that are orthogonal to the direction of loading and which provide partial resistance to the applied loading. In order for this tube action to be effective, it is found that the frame tube should deflect like a cantilever with linear variation of axial force in the columns of the longitudinal frames and almost uniform axial force in the columns of the transversal frames. The key parameter that governs the inelastic dynamic response of frame tube structure was found to be the change of the post elastic story stiffness from the elastic story stiffness. For a large change of story stiffness, the bottom stories suffered large interstory drift. However, by decreasing such changes, the interstory drift became more evenly distributed along the height of the structure.

The inelastic response when the frame tube is subjected to a bidirectional excitation is finally presented. It is found that the approximate estimates suggested by design codes underestimate the response. An alternative was proposed to give a more realistic estimate. Such scheme is the simple summation rule.

abstract: Doctor of Philosophy (PhD)


title: The Effects of some Inert Carbonaceous Additives on the Mechanical and Optical Properties of Coke

contributor:
Lu, W.K.
Chemical Engineering

subject:
Chemical Engineering
Chemical Engineering

abstract:
The objectives of the present study were to investigate, under laboratory conditions, the strength of coke as a function of some of the key variables in the carbonization process, including the addition of some inert carbonaceous materials, and to analyze the effects of these additions on the optical properties of a particular high fluidity coal (Devco). Three coals were selected; Devco, a Canadian coal, and Madison and Chisholm both of which are American coals. Three inert carbonaceous additives were used; Devco semicoke (carbonized at 500°C), low temperature Devco coke (carbonized at 700°C), and coke breeze.

The experimental work was divided into two parts. In the first part, a full factorial design was planned and the blends of Devco coal were carbonized according to it. The variables investigated were: heating rate, size, amount, and 'type' of the inert carbonaceous blended. The dependent variable was the microstrength index (MSI). It was found that the 'type of inert' had the largest statistical weight on the results. The content and mean particle size of the additive in the blend and their interactions with the 'type' were also very significant in the strength. An empirical equation was obtained to express MSI as a function of these variables. In the second part, the blends of the three coals were carbonized according to another statistical design to investigate the following variables: heating rate, type of coal and type of inert. The 'type of coal' was found to be the most statistically significant variable. Nevertheless, the type of inert changed drastically the mechanical properties.

In single coal experiments the blending of Devco semicoke-500°C increased the MSI (i.e., 10% addition raised the index in Madison by 28%, Chisholm by 28% and Devco by 18%). On the other hand, the blending of coke breeze caused the MSI to drop (10% addition reduced the index in Madison by 29%, Chisholm by 22% and Devco by 19%). The type of inert was characterized by its microhardness, true specific gravity, and ash and volatile matter contents. The type of coal was described by an empirical function derived from accepted industrial correlations.

A relationship has been established between microstrength index and tensile strength based on data of the present work. Several samples of cokes were analyzed under the SEM and the optical microscope. It was observed that the addition of Devco semicoke-500° and low temperature Devco coke-700°C reduced the amount of isotropic carbon present in the structure; these blends also had the higher strength.

abstract: Master of Engineering (ME)


title: Electrical Responses of Human Muscles During Fatigue and Recovery

contributor:
McComas, Alan J.
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract:
The studies composing this thesis were designed to address the question of changes in muscle excitability during fatigue and recovery: the indirectly-evoked muscle compound action potential (M-wave) was used as an index of excitability. Earlier studies from this laboratory indicated that the rate of fatigue in human skeletal muscle depends on the frequency of excitation. The present studies have extended these findings by using a wide range of stimulating frequencies (0-30 Hz) and by comparing the change in muscle excitability in fast-versus slow-twitch muscles; the effect of ischaemia was also studied as was recovery from fatigue. Ten subjects (out of a total of fifteen) each successfully completed five experiments, spaced at least one week apart, in which intermittent tetanic trains at different frequencies were used to fatigue the ishaemic ankle dorsiflexors. The effects of ischemia were studied by repeating one experiment under non-ischaemic conditions. Five out of the ten subjects also volunteered for the experiments comparing changes in muscle excitability in soleus, versus those in tibialis anterior, in response to intermittent fatiguing stimulation.

It was found that maintenance of excitability was possible for one minute regardless of stiumulus frequency; thereafter stimulation at the highest frequencies induced the greatest change in the amplitude of the (M-wave). The amplitude decline was also dependent on the position of the M-wave within the train of potentials: thus, at 30 Hz stimulation, the first, fourth and seventh responses within the trained decreased by 50%, 80% and 95% respectively (p<.01). The decline in M-wave amplitude was always greater than the decline in the area of the compound action potential, indicating an increase in duration due to dispersion of single fiber action potentials. At 30 Hz stimulation the areas of the first, fourth and seventh responses decreased by 33%, 56% and 82% respectively.

On the basis of animal studies, it was hypothesized that muscle excitability would be preferentially retained in the soleus muscle; however, no significant differences emerged in M-wave changes between soleus and tibialis anterior although the onset of decline was delayed in soleus. It is proposed that this delay was due to the early potentiating mechanisms observed in soleus but not in tibialis anterior. The presence of ischaemia significantly (p<.01) accelerated the decline in both amplitude and area of the tibialis anterior M-wave. Recovery of the M-wave was limited when the tetanic stimulation ceased but progressed rapidly after the circulation was restored. M-wave failure occurred at firing rates not normally associated with neuromuscular blockade, implying propagation failure along the sarcolemmal membrane.

abstract: Doctor of Philosophy (PhD)


title: Cree Baby Talk and Universal Baby Talk

contributor:
Colarusso, John
Anthropology

subject: Anthropology Anthropology

abstract:
The intent of this thesis is to identify the lexical, syntactic/inflectional and phonological features of East Cree Baby Talk (henceforth BT) as a way of understanding how children acquire the highly complex standard adult (SA) forms. I demonstrate that the early linguistic features are universal and that significant variation among languages occurs subsequent to the BT stage.

As a result of comparative analysis I am able to conclude:

1. East Cree BT exemplifies universal features of BT;

2. The acquision of BT represents a level of generalized language learning;

3. Language learning is hierarchical;

4. As languages develop, they diverge and give rise to the greatly varied SA surface structures;

5. The occasional variation that occurs in BT registers can be explained in terms of the salient or difficult features of the target language;

6. BT universals are generally absolute, non-implicational and stubstantive;

7. Absolute, non-implicational and substantive universals precede statistical, implicational and formal universals;

8. The deep structure of SA speech is similar to BT and, in a sense, develops out of it. Thus, deep structures are cognitively concrete while SA surface structures are cognitively abstract.

For three of the comparative languages used in this study I depend upon secondary data. Due to the problems encountered, I suggest steps to improve methodology in the recording, presentation and analysis of BT material.

abstract: Doctor of Philosophy (PhD)


title: Changes in Muscle Action Potentials During Activity: The Role of the Na⁺-K⁺ Pump

subject:
Medical Sciences
Medical Sciences

abstract: The studies that make up this thesis have been designed to describe and analyse the changes in muscle action potentials associated with muscular activity. The initial experiments were carried out in human muscle to examine changes in the muscle compound action potential (M-wave) during both stimulated and voluntary activity. It was found that the M-wave increased in amplitude either during or following either type of activity, and that this increase in M-wave amplitude could not be explained by either a movement artefact or a greater synchronization of action potential firing. It was hypothesized that the potentiation of the M-wave was due to a hyperpolarization of the muscle fibre membrane which was increasing the amplitude of the individual fibre action potentials. Experiments were then conducted on rat soleus muscle (in vivo) in order to measure changes in resting membrane and action potentials associated with contractile activity. After 5 min of intermittent tetanic stimulation at 20 Hz, the mean resting membrane potential increased from a baseline value of 79.5 ± 4.8 mV to a mean maximum of -92.6 ± 4.2 mV 3-6 min post-stimulation (p<.01). There was a corresponding increase in action potential amplitude; it rose from a resting value of 82.2 ± 10.8 mV to 98.1 ± 7.8 mV in the recovery period (p<.01). It was hypothesized that increased activity of the electrogenic Na⁺-K⁺ pump was causing the hyperpolarization. A series of experiments utilizing inhibitors of the Na⁺-K⁺ pump were then conducted; it was found that the administration of ouabain (1.25 x 10⁻⁴M), cooling the bathing medium (from 37°C to 19°C) or removal of extracellular K⁺ prevented the hyperpolarization following repetitive stimulation (p<.05). The magnitude of the electrogenic contribution of the Na⁺-K⁺ pump was then estimated by exposing stimulated muscle fibres to a high K⁺ (20 mM) medium. While in the control (unstimulated) condition this caused an immediate depolarization of the muscle fibre membrane to approximately -58 mV, stimulated fibres maintained membrane potentials of -79.5 mV (± 8.6 mV) for at least 3 min, which was approximately -30 mV greater than that predicted by the Goldman-Hodgkin-Katz (GHK) equation. It is concluded that the Na⁺-K⁺ pump plays an important role in maintaining muscle fibre excitability during muscular activity, which is additional to its role in the restoration and maintenance of ionic gradients for Na⁺ and K⁺. The temporary hyperpolarization of the muscle fibre membrane during increased Na⁺-K⁺ activity offers an explanation for the potentiation of muscle compound action potentials observed during voluntary and stimulated contractions.

abstract: Doctor of Philosophy (PhD)


title: Control of Robotic Fixtureless Assembly

contributor:
Bone, Gary M.
Elbestawi, M. A.
Mechanical Engineering

subject:
Mechanical Engineering
Mechanical Engineering

abstract: Robotic Fixtureless Assembly (RFA) refers to the performance of assembly tasks by robots without the aid of jigs and fixtures. Two control problems encountered in RFA of sheet metal parts assembly are addressed in this thesis. They are the control of vibration when handling the sheet metal parts and the control of the contact state between the parts during assembly. Both 2-D parts and 3-D parts will be considered when the two problems are addressed. A unique sensor, termed a Strain Gauge equipped Finger (SGF), was first developed which can measure the part's vibration during handling and the contact state during assembly. For the vibration control problem, a novel Learning Extremum Control (LEC) algorithm is proposed. Using SGF's mounted on the robot gripper for vibration feedback, the orientation of the part in 3-D space relative to its path is controlled to reduce vibration. Furthermore, as an alternate approach, a feedforward Input Command Shaping Method (ICSM) is employed to reduce the vibration. Experimental results confirmed the effectiveness of both control algorithms. The LEC and the ICSM reduced the vibration amplitude by up to 71% and 78%, respectively. In order to solve the contact state control problem, the contact state measurement problem in 2-D parts assembly is first considered. Measurement methods are developed based on the use of a Force/Moment Sensor (FMS) alone, SGFs alone and the sensor fusion of he FMS and SGFs information. The methods are verified in 160 robotic assembly trials. The success rate for the FMS method increased from 28% to 88% when the sheet thickness was increased from 0.32 mm to 1.88 mm. Under the same conditions, the success rate for the SGF method decreased from 100% to 55%. The sensor fusion method surpassed the best individual performances off the other methods by achieving a 100% success rate for the complete set of sheet thicknesses and contact states tested. After the contact state measurement problem is considered, the contact state control problem is examined. The SGFs a Force/Moment Sensor (FMS) are used to provide feedback about the contact condition between two sheet metal parts. An Integral Contact Controller (ICC) is used to correct angular error between the parts to ensure full contact along the joints for subsequent welding. Experimental results confirmed the effectiveness of the ICC algorithms. For 2-D parts, using the fusion of the FMS and SGF sensory information, the ICC reduced the Yaw joint angular error from 0.5˚ to 0.025˚ within 1.7 seconds. For 3-D parts, the ICC reduced the angular error in both the Pitch and Yaw angles from 0.5˚ to 0.05˚ within 2.4 and 3.6 seconds using the FMS alone and SGFs alone, respectively. Finally, an investigation is performed to determine the effectiveness of applying the Input Command Shaping Method in the contact state control experiments. This method's limitations are discussed.

abstract: Doctor of Philosophy (PhD)


title: Cultural Influences in Deceptive Communication

contributor:
Carment, D.W.
Psychology

subject: Psychology Psychology

abstract:
Researchers in deceptive communication have suggested that beliefs about deceivers (e.g., Hocking & Leathers, 1980; Ramsey, 1979), and the behavioural changes exhibited by deceivers (e.g., Ekman & Friesen, 1972; Feldman, 1979), and the accuracy with which deceptive messages can be detected (Atmfyanandana, 1976; Ekman, 1985) are influenced by cultural factors. To date, there has been no empirical evidence to support these hypotheses.

The purpose of research presented in this thesis was to examine the role of cultural factors in deceptive communication. To this end, Canadian and Chinese students were compared regarding their attitudes towards deception, their beliefs about the behavioural changes exhibited by deceivers, the behavioural changes exhibited during deception, and their judgements of the sincerity of communicators.

The results of this research indicated that, compared to Canadian students, Chinese students rate lying as less morally wrong, and believe people to exhibit significantly fewer behavioural changes when telling lies. Analyses of judges' assessments of the sincerity of Canadian and Chinese communicator revealed that messages by Chinese female communicators were judged more accurately than messages by Chinese male communicators. This gender difference was not apparent in ratings of the messages by Canadian male and female communicators. Differences were also found in Canadian and Chinese students' assessments of the sincerity of the communicators. Chinese judges, rated the sincerity of the communicators as higher than did the Canadian judges, and Chinese judges were less accurate at detecting deceptive messages by Canadian communicators than were the Canadian judges.

Misattributions of insincerity or inappropriate expectations regarding sincerity can promote negative cultural stereotypes and inhibit effective communication between interactants from different culturaI backgrounds. Awareness of differences in attitudes and beliefs about deception, and in assessments of the sincerity of communicators may help to facilitate communication and understanding between Canadian and Chinese individuals.

abstract: Doctor of Philosophy (PhD)


title: Discourses on Communication Technologies

contributor:
Knight, Graham
Sociology

abstract: This dissertation is a sociological study which examines discourses on communication technologies through public proceedings in the process which led to Canada's 1991 Broadcasting Act. The methodological basis of the study is historical, qualitative research (mainly utilizing t he transcripts of governments committee proceedings and debates). The study considers a theoretical problem. The theoretical problem involves understanding how the discourses of technological causality, technological democracy, and technological nationalism figure into the struggle over hegemony among social agents. The public proceedings which led to the 1991 Broadcasting Act, and the social agents which participated in those proceedings, provide an empirical basis for grappling with he theoretical problem. The study presents an argument in relation to the theoretical problem which it addresses. This argument suggests that: a) the discourse of technological causality played a role in the process of establishing private capital's hegemony within Canadian broadcasting; b) the discourse of technological democracy played a similar role while becoming the target of a counter hegemony which favoured community broadcasting; and c) the discourse of technological nationalism played a role in the process of securing the federal state's hegemony over its institutional components and the regions (as well as efforts to strengthen national public broadcasting), but the discourse became the focus of a counter hegemony which eventually led to its transformation.

abstract: Doctor of Philosophy (PhD)


title: On the Application of Single Loop, Decoupling and Davison's Robust Control to a Heat Exchanger-Stirred Tank Process

contributor:
Taylor, P.A.
Wright, J.D.
Chemical Engineering

abstract:
Three different control strategies are compared in the control of the output temperature and the total flowrate of a heat exchanger stirred tank process: single loop control, Davison's robust control and decoupling control.

When the single loop control was applied, interactions between the process variables were observed when the flow setpoint was changed. This resulted in large oscillations in the temperature. The load responses were, however, satisfactory. It was shown that Davison's robust controller was similar to a static decoupler using two integral feedback controllers of the same gain. The integral mode alone was not found to be adequate for the control of the slow temperature process. Static decoupling gave satisfactory results for both setpoint and load changes. There was some improvement, although-not very great, when dynamic decoupling was applied. This was because the cross and direct dynamics of the temperature processes had approximate time constants.

abstract: Master of Engineering (ME)


title: Wavelet Packet Division Multiplexing

contributor:
Wong, K. M.
Electrical and Computer Engineering

abstract: Wavelet Packet Division Multiplexing (WPDM) is a multiple signal transmission technique in which the message signals are waveform coded on wavelet packet basis functions for transmission. It has the advantage of a parallel transmission system, but the overlapping nature of such waveforms in time and frequency provides a bandwidth efficiency improvement over the Frequency Division Multiplexing (FDM), whilst their orthogonality properties ensure that the overlapping message signals can be separated by a signal correlation receiver. The interface caused by timing errors in the receiver is examined, and modeled as the information signal sequence filtered by interference filters. A design procedure which exploits the inherent degrees of freedom in the WPDM structure to mitigate the effects of timing error is introduced and a waveform which minimizes the energy of the timing error is introduced and a waveform which minimizes the energy of the timing error interference is designed. An expression for the probability of error due to the presence of Gaussian noise and timing error for the transmission of binary data is derived. The performance advantages of the designed waveform over standard wavelet packet basis functions are demonstrated by both analytical and simulation methods. The performance of WPDM in impulsive noise and Gaussian noise is analyzed, simulated, and compared with the performance of a commonly used serial transmission system, Time Division Multiplexing (TDM). The results support the instinct that WPDM as a parallel transmission system provides greater immunity to impulsive noise than TDM. The performance of WPDM in fading channels is analyzed, and the time domain equalization technique - Pilot Symbol Assisted Modulation (PSAM) - is applied to suppress the error floor which is common in digital communication with coherent reception in fading channels. The derivation and simulation show that in flat fading channels, the error floor in WPDM is suppressed as successfully as FDM with the PSAM, and the frequency of pilot symbols used in WPDM is less than that in FDM to acquire the sufficient channel estimation, thus the WPDM wastes less capacity and energy on pilot symbols than FDM. The analysis of WPDM in two-ray frequency selective fading channels with PSAM is done, and shows that error floor is also suppressed to some extent, but not as striking as for flat fading channels. The reason for this is revealed in the analysis. The bandwidth efficiency improvement of WPDM, its simple implementation, its greater immunity to impulsive noise, and its good performance in fading channels indicate that WPDM holds considerable promise as a multiple signal transmission technique.

abstract: Doctor of Philosophy (PhD)


title: Moving Finite Element Solution of Discontinuous Open Channel Flow

contributor:
Smith, A.A.
Lam, D.C.L.
Civil Engineering

subject:
Civil Engineering
Civil Engineering

abstract:
Over the years, rapidly varying channel flow and discontinuities in the solution of fluid mechanics problems have provided stimulation and challenge to numerical modelers. Traditional finite difference and finite element methods produce accurate but oscillatory solutions. Attempts to selectively eliminate these parasitic waves have been only partially successful in that the cost of a smoother profile was a lower accuracy solution. It is common to employ either internal and external dissipation parameters or a provision of dispersive interface.

In this thesis, the problem of rapidly varying open channel flow is represented by a pair of nonlinear partial differential equations which are solved by a powerful moving finite element technique. The method developed in this research is based on the linking of a novel Lagrangian mode solution with the convenience of the Eularian grid at each time step. This second order scheme was employed in solving a variety of devised and reported open channel flow problems with near discontinuities.

Comparisons with solutions obtained using the finite difference and finite element methods with Crank-Nicholson centred weightings demonstrates the quality improvements which have been achieved by this moving element scheme. The basic scheme was further generalized in both spatial and temporal dimensions. Sensitivity analysis of these generalized parameters established the grid size relaxations for a variety of problems. The moving element technique solved near discontinuous and gradually varied flow problems both in supercritical and subcritical regimes.

An alternate form of Petrov-Galerkin weighting function was tested and found to give promising results. Further experimentation and testing are required before implementation.

The robustness of the solution procedure is indicated by the adaptation of the model from the numerical and laboratory experiment stage to field problems. The model was successfully applied to the Teton Dam break flood and flood routing problem in the (Ontario) Grand River basin. Sensitivity analysis with very mild sloped channels with topographical features such as sudden expansions and offchannel storage suggest that the Eulerian-Lagrangian mode algorithm provides the missing link between the fluid mechanics of discontinuities and a practical tool for the modelling of rapidly varying open channel flow.

abstract: Doctor of Philosophy (PhD)


title: Single-phase Unidirectional Transducers for Low-loss Surface Acoustic Wave Devices

contributor:
Campbell, C.K.
Electrical Engineering

abstract:
There has been an upsurge in interest recently in lower loss surface acoustic wave (SAW) devices for new signaI processing applications. In this thesis, a new generation of unidirectional transducers (UDTs) for the realization of low-loss SAW devices has been studied in which unidirectionaIity is effected by exploiting coherent internal reflections within a transducer. These single-phase UDTs (SPUDTs) offer many advantages and attractions that are unavaiIable in many previous UDT designs. CoupIed-mode theory is extensively used to analyze and characterize these structures. A general theory is proposed which will guide design and construction of all SPUDT devices. This includes specifications of the optimum conditions for achieving maximum directivity. An accurate and detailed model is also developed for SPUDTs with inter-IDT reflectors. The model accounts for all major electrode interaction effects and involves the cascade of transfer matrices of reflectors, transmission lines and transducers to realize the overall response. Experimental verifications have consistently shown that this model is very accurate in the analysis of SPUDTs.

Based on a better understanding of the SPUDT concept, several new SPUDT designs have been developed. Special efforts are expended towards acquiring key properties never before obtained with SPUDTs, such as improved sidelobe suppression, wider bandwidths and higher operating frequencies. In these respects, the new designs represent a significant improvement over the earlier SPUDT designs. The final part of the thesis describes the theory and operation of a novel SPUDT-based multimode oscillator for frequency agile radar. An innovative injection-locking scheme involving FM chirp-mixing is also disclosed. Preliminary tests have indicated very encouraging results including low phase noise levels (120 dBc/Hz @ 10 kHz), wide tuning bandwidth (50%) and fast switching speeds (< 2 us).

abstract: Doctor of Philosophy (PhD)


title: On the rules-to-episodes transition in classification: Generalization of similarity and rules with practice

contributor:
Brooks, L. R.
Psychology

subject: Psychology Psychology

abstract: When classifying a novel object, people often rely on similarity to previously learned instances to help them identify the category of the object. People also rely on more analytic knowledge, like classification rules, to identify the category of a novel object. The coexistence of two different procedures that could be used to classify the same novel object. The coexistence of two different procedures that could be used to classify the same novel object raises the issue of coordination; that is, what is the relation between rule-based and similarity-based classification. Learning a new category is much like acquiring any cognitive skill, therefore it is hypothesized that current theories of skill acquisition should provide a useful framework for studying the relation between rule-based and similarity-based classification. A popular view of skill acquisition, Logan's Instance Theory (1988), suggests that skilled performance can develop rapidly, possibly after only a few practice trials on specific instances. The underlying basis of this rapid skill development is attributed to a transition from reliance on slow analytic procedures to reliance on faster retrieval-based procedures. Given what is known about memory, this transition to a retrieval-based classification procedure makes a great deal of intuitive sense and should account for the faster, more efficient classification performance that is characteristic of highly practiced individuals. The experimental conditions were designed to test an extreme example of this transition from rule-based to retrieval-based categorization. If a transition to a fast, retrieval-based procedure is a reasonably automatic result given sufficient practice, then it should occur even when participants are given a classification rule that is simple, perfectly predictive, and easy to apply. Although there was some evidence of participants relying on similarity to prior instances for classification, this reliance on similarity never approached the levels that would be expected if participants had abandoned the rule. In fact, a reliance on similarity was limited to novel stimuli that were so similar to the training stimuli that they were actually falsely recognized as old. When people realized a novel stimulus as new, they relied on the classification rule. This "retrieve if believed old, rule if believed new" strategy held across a number of manipulations all designed to facilitate an increased reliance on similarity including extensive practice, training with multiple similar neighbors, speeded classification, and reducing the novelty cues present witthin the transfer stimuli. Continued reliance on rules to classify novel items believed to be new and false recognition of novel items believed to be old raises questions about the role of similarity and the assumptions that a transition from rules to retrieval is a relatively automatic occurrence of skilled classification.

abstract: Doctor of Philosophy (PhD)


title: Emotion and Behaviour

contributor:
Siegel, L.
Psychology

subject: Psychology Psychology

abstract:
A method of examining how emotions might affect learned behaviour was developed and thre hypotheses concerning the possible effects of emotions were investigated. The first was that emotions may have state-dependent properties by which they affect the display of learned behaviour. A behaviour learned in the context of a particular emotion may be more likely to occur when that same emotion is experienced subsequently. This hypothesis was supported by the finding that four-year-old children responded non-aggressively when frustrated if this behaviour had previously been learned in the context of frustration. They did not respond aggressively when frustrated if aggression had been learned in the context of non-frustration. The second hypothesis was that behaviour learned during emotional arousal is more likely to occur subsequently, perhaps because it is better remembered, than is behaviour learned in a less emotional situation. This hypothesis was only partially supported. The third hypothesis was that some behaviours are prepared responses and are more likely to be learned in the context of some emotions than are other behaviours. There is evidence suggesting that aggression might be more easily learned or displayed in the context of frustration than non-aggressive behaviours. This hypothesis was not supported. Although there was a consistent sex difference in aggression, the amount of aggression by either sex was not affected by the presence of frustration, either during learning or testing.

The results support the usefulness of the methodology and indicate that emotions affect the display of voluntary, purposeful behaviour, especially in a state- or context-dependent manner. Some implications of these results for the study of emotions, as well as criticisms of the thesis experiments, are discussed.

abstract: Doctor of Philosophy (PhD)


title: Sports Crowd Disorder, Mass Media and Ideology

contributor:
Knight, G.
Donnelly, P.
Shaffir, W.
Sociology

subject: Sociology Sociology

abstract:
An examination of the hundreds of books and articles produced by sociologists of sport reveals, amongst other things three important omissions in this Iiterature: (1) until recently little serious attention has been paid to the disorderly behaviour, roles and rituals of sports spectators, and to the way their behaviours are broadly interpreted and understood in dominant ideology; (2) there is a lack of cross-cultural studies of sport and sports crowd behaviour; (3) there is a paucity of information on the role of the mass media in sports violence in general, on how the media treat sports crowd disorder and on how, if at alI, their treatment contributes towards dominant ideologies of the issues involved.

The study attempts to redress the neglect in these areas by examining the relation between sports crowd disorder, the mass media and ideology in two different or international contexts; the United Kingdom and North America. The theoretical framework employed derives from Marxist theories on the production and reproduction of ruling or 'hegemonic' ideas, and has been broadly adopted by an inter-disciplinary group of scholars working at the Centre for Contemporary Cultural Studies at the University of Birmingham, England. Essentially, 'cultural studies", as the mainstream perspective of this group is now called, uses a critical-materialist concept of ideology to show how ideology is created and signified, and how it shapes the public consciousness.

In compliance with multiple-method approaches advised by cultural studies, data were collected by way of a synthesis of methods, including: (1) semiotic content analysis of media reports of sports crowd disorder and sports violence; (2) interviews and observations with involved parties (sports spectators, sports organizations, media personnel, etc.,); (3) a questionnaire distributed to professional sports organizations in North America.

The study shows that the media play an active, not passive, role in sports crowd disorder and that partially due to differential techniques of media coding and signification, dominant ideological understandings of sports crowd disorder in the United Kingdom and North America are very different. In essence, while reports of and responses to British soccer hooliganism have displayed all the classic symptoms of moral panic, any presence or threat of sports crowd disorder in North America appears to be consistently downplayed (by official and unofficial parties) if not denied in more explicit terms.

abstract: Doctor of Philosophy (PhD)


title: Chemical and Biological Characterization of Southern Ontario Urban Air Particulate

contributor:
McCarry, B.E.
Chemistry

subject:
Analytical Chemistry
Chemistry
Analytical Chemistry

abstract: Ambient concentrations of polycyclic aromatic compounds [PAC], other air pollutants and the mutagenic potency of respirable air particulate extracts were used to study air quality in Hamilton from May of 1990 to June of 1991. Concentrations of polycyclic aromatic hydrocarbons [PAH], thiaPAH, oxygenated PAC and in some cases nitroPAH as well as the mutagenic activity caused by these compounds were determined in 68 samples of air particulate, collected over a number of days with widely varying air pollutant concentrations and atmospheric conditions. Chemical analyses of the non-polar aromatic fractions of the air particulate extracts showed a 550-fold range in PAC concentrations, from 0.31 to 170 ng/cubic metre air, while biological assays showed a 140-fold range of mutagenic potencies. The non-polar aromatic fraction represented about three-quarters of the sum of the mutagenic responses in the polar and non-polar aromatic fractions. The mutagenicity and PAC concentrations of air particulate collected in Hamilton are low to average compared to air particulate samples collected in other cities around the world. Relationships between mutagenic potencies, PAC concentrations and atmospheric condistions were examined using principal component analysis, which revealed good positive correlation between the mutagenic potencies of the non-polar aromatic fractions, nitrogen diozide and sulfur dioxide concentrations. Average windspeed and ozone concentrations were inversely correlated with mutagenicity. Principal component analysis also show that sprigtime thermal inversion episodes correlated with conditions favoring the atmospheric transformation of PAH to mutagenic nitroPAH. The mutagenic potency of the non-polar aromatic fraction of air particulate extract rose in direct proportion to nitroPAH concentrations arising from atmospheric transformation. Enhanced-sensitivity strains of Salmonella typhimurium were used in all bioassays of air particulate extract mutagenicity, thereby making more extract available for extensive chemical analyses. For example, bioassay analyses of a pooled sample of air particulate extract were carried out using six different strains of S. typhimurium. Strains containing increased levels of enzymes responsible for metabolizing compounds such as nitroPAH showed 7- to 10-fold enhance mutagenic responses compared to standard tester strains. Normal-phse HPLC seperation of the non-polar aromatic fraction of the pooled air particulate extract was combined with bioassays utilizing three different enhanced-sensitivity S. typhimurium strains, allowing quantitation of individual mutagens through analytical chemical methods as well as accurate determination of the mutagenic activity arising from each compound. Normal-phase HPLC separation was also used in the bioassay-directed fractionation of an extremely mutagenic air particulate sample collected at the side of Highway 404 in Toronto, Ontario. NitroPAH arising from combustion sources were determined to be responsible for virtually all of the mutagenic activity detected in this particular sample, from which was isolated a potent mutagen not previously described in air particulate extracts -3.8-dinitrofluoranthene.

abstract: Doctor of Philosophy (PhD)


title: Steroid-induced growth delay and bone abnormalities in preterm infants and piglets during early development: the interaction of steroids and the GH-IGF-I axis

contributor:
Atkinson, S.A.
Medical Sciences

subject:
Medical Sciences
Medical Sciences

abstract: Dexamethasone (DEX) treatment in very preterm infants has proven to facilitate earlier weaning from mechanical ventilation and supplemental oxygen, thereby lessening the severity of lung disease incurred by long-term oxygen dependency. However, DEX therapy is not without negative side-effects; studies in preterm infants and piglets have reported DEX-induced impairments in growth and bone mineral metabolism. DEX may act by altering the concentration or activity of specific components of the growth hormone (GH)/insulin-like growth factor (IGF-I) axis which are essential for regulating growth and bone mass. The first study, in preterm infants, characterized how DEX alters the circulating components of the GH-IGF-I axis and suggested potential mechanisms by which DEX delays growth and bone development as both plasma IGF-I and biochemical markers of bone metabolism were reduced during DEX. The objectives of the piglet studies were to delineate the effectiveness of adjunctive GH or GH+IGF-I to counter the detrimental effects of DEX on growth, protein turnover and bone mass. In the first studies, we administered GH, GH+IGF-I or placebo to piglets while they received a two week course of DEX. GH and GH+IGF-I partially attenuated the reductions in growth and bone mas to a similar extent. Only with respect to protein metabolism was an additional benefit observed with combined treatment (GH+IGF-I). A dose-response study revealed the minimal effective GH dose, and demonstrated that bone cell activity and weight and length gain returned to control levels during a period of rehabilitation in which no DEX or GH were administered. Currently, it is uncertain if DEX-treated infants experience similar metabolic improvements in weight and length growth or bone mineral mass post-DEX treatment or whether the metabolic insults of DEX are sustained. Longer term follow-up of DEX-treated preterm infants is required to fully comprehend to long-term consequences of DEX on growth into childhood. If there are long-term effects on growth and bone development, future studies should focus on whether GH is more effective post-DEX compared to during DEX treatment or whether adjunctive administration of other anabolic agents will counter the negative effects of DEX during development.

abstract: Doctor of Philosophy (PhD)


title: The Causes and Effects of the 1981 Hospital Strike in Ontario: Fiscal Crisis, Changing Labour Process and the Role of Gender in Public Sector Conflict

contributor:
Cuneo, Carl J.
Sociology

subject: Sociology Sociology

abstract:
In 1981 the Canadian Union of Public Employees (CUPE) staged a strike in Ontario Hospitals. This dissertation is an exploratory case study of the causes and effects of that strike. The dissertation employs elements of the labour process theory to evaluate the hospital worker's action and in so doing provides an opportunity to contribute to the on-going debate concerning this theory. The study is centred on the hospitals of Greater Hamilton and Burlington Ontario. It assesses the role of political environment, union structure and action, and gender in creating and sustaining the conditions for strike action in the public sector.

The economic and political situation leading to the strike is analyzed with a view to understanding how the fiscal crisis in Canada led to the strike. Labour legislation and the fiscal policies of the federal and provincial governments had an impact on hospitals and their workers. Labour legislation in the hospital sector destroyed collective bargaining at a time when changes unpopular with the workers were taking place in the hospital. This encouraged the decision to strike.

The majority of hospital workers in 1981 were women. The dissertation explores, through interviews and archival data, a possible link between gender and the decision to strike. Some changes in the organization of hospital work broke an important care-giving link between women workers and patients.

The repercussions of the strike include charges for the union, for women, and the wider political consequences such as the further undermining of the Hospital Labour Disputes Arbitration Act.

The dissertation concludes that the strike was caused by labour process changes made by management faced with government cost cutting measures. These changes were particularly upsetting to the majority of workers who were women. The illegality of the strike did not deter the decision to strike because the government labour legislation had destroyed the 'normal' bargaining process. Therefore workers felt that there was no real choice but to strike.

abstract: Doctor of Philosophy (PhD)


title: Geological and Geochemical Studies of the Gold-Bearing Quartz-Fuchsite Vein at the Dome Mine, Timmins Area

contributor:
Crocket, J. H.
Geology

subject: Geology Geology

abstract:
The Quartz-Fuchsite vein at the Dome Mine, Timmins area, has been the subject of an integrated field, petrographic, geochemical, and fluid inclusion study to characterize the site and the cause of ore deposition, and to establish the source of ore components in Archean lode gold deposits.

The vein lies in a zone of carbonatized komatiites at the contact with a unit of slates. The wall rock alteration that accompanied ore genesis is centered around a porphyry lens located in the zone of carbonatized rocks. The location of the Quartz-Fuchsite vein is coincident with the outer rim of the alteration envelop.

A high pore fluid regime that developed in the carbonatized komatiites in proximity to the slates resulted in hydraulic fracturing and genesis of the Quartz-Fuchsite vein. Massive and barren quartz was deposited during protracted stages of fracture growth, while banded and gold-bearing quartz was formed during repetitive and brief periods of crack-seal vein growth. Quartz veining took place before the compressional deformation which has affected the Timmins area.

Fluid inclusion studies indicate that the hydrothermal fluid contemporaneous with quartz veining and gold deposition was a low salinity CH₄-rich H₂O-CO₂ fluid that underwent intermittent unmixing. Phase separation was promoted during pressure drops in fractures that accompany the crack-seal vein growth mechanism. The strong partitioning of CO₂ and CH₄ into the vapor during unmixing resulted in a shift in the remaining fluid toward higher pH and fO₂. As a consequence, gold complexes were probably destabilized in the hydrothermal fluid and deposited with quartz in crack-seal veins.

Lead isotope studies of whole rocks and galenas associated with gold in the Quartz-Fuchsite vein suggest a genetic link between the gold mineralization and the quartz-feldspar porphyries of the Dome Mine environment, although other source reservoirs cannot be ruled out on the basis of lead isotopes alone. Sulfur isotope compositions of pyrites and galenas from the Quartz-Fuchsite vein are compatible with a magmatic or a metamorphic fluid.

The weight of evidence indicates that the development of the gold mineralization in the Quartz-Fuchsite vein is genetically related to the emplacement of quartz-feldspar porphyries in the Dome Mine environment. The ultimate source of gold and the mineralizing fluid is probably a deeper seated magma, or possibly the lower crust.

abstract: Doctor of Philosophy (PhD)


title: Development of an Effective Model for Particle Size Distribution in Suspension Copolymerization of Styrene/Divinylbenzene

contributor:
Wood, Philip E.
Hamielec, Archie E.
Penlidis, Alexander
Chemical Engineering

abstract: An effective mathematical model for estimation for the Particle Size Distribution (PSD) in suspension copolymerization of styrene/divinylbenzene has been developed. Its effectiveness is shown as a compromise between a sound theoretical basis and the simplest possible mathematical structure, which makes possible the solution of the governing equations using conventional computational tools. In building the model, a comprehensive and systematic approach was undertaken. The first stage of this approach was to critically review and analyze the literature in suspension polymerization. The most important weaknesses and deficiencies of the existing models and the approaches used to build them were identified, and a strategy to overcome them was designed and implemented. The second stage of the approach was to identify the key factors that control the PSD, and build mechanistic mathematical models of an intermediate and balanced degree of complexity. The third stage consisted of incorporating these mechanistic models into a macro-scale model of the PSD. Using novel experimental design techniques, the relative importance of the different factors on the PSD, and the aspects of the model that needed refinement were determined. The final stage consisted of implementing changes to the model in a balanced and effective way. The result was an improved model for PSD that assigns adequate weight to the importance of each key factor, with similar degree of complexity as the best models reported in the literature, but better performance and increased reliability of predictions. Some of the contributions of this thesis to the field of Polymer Science and Engineering include: the development and validation of an effective model for crosslinking free-radical copolymerization kinetics; the establishment of prescriptions to guide the efforts in the acquisition and interpretation of information aimed at improving our understanding and modelling capabilities of suspension polymerization reactors; the inclusion, for the first time in suspension polymerization modelling, of non-homogenous mixing in the stirred tank reactor into the PSD model; the development of mathematical models for breakage and coalescence in liquid-liquid dispersions, and the systematic and effective use of mechanistic modelling for experimental design purposes in polymer production studies.

abstract: Doctor of Philosophy (PhD)


title: Variable Source Area Modeling in Urban Areas

contributor:
Tsanis, I. K.
Civil Engineering

subject:
Civil Engineering
Civil Engineering

abstract: A variable source area model called TOPMODEL was modified to incorporate urban areas in both the topographic index and the mechanism of surface runoff generation. The revised model was applied to a small catchment in the Hamilton-Wentworth area. A Geographic Information System was utilized to delineate the Ancaster Creek Catchment and produce Digital Elevation Models (DEM). FORTRAN programs in conjunction with the DEM were used to compute topographic indiced that explicitly accounted for urban areas. Additional FORTRAN programs were modified to determine flow rates from this semi-urbanized catchment. Model testing was conducted in three phases: 1)a study of aggregation and scale effects using a partially revised model (TOPURBAN v.1) on three separate time periods; 2) a fully revised model (TOPURBAN v. 2) tested on six time periods; 3) comparisons between a conventional Hortonian flow model and TOPURBAN v. 2. Ten different DEM sizes were used to compute topographic indiced and TOPURBAN v. 1 was applied during the snow-free period of a wet, dry and median year. Four separate parameters were optimized. The results indicated that three of the four calibrated parameters varied only slightly with DEM size but the hydraulic conductivity increased with increasing grid cell size. Twenty-one statistics were compute to evaluate TOPURBAN v. 1's performance for predicting flow with regard to DEM size. The statistics indicated that the DEM size of 50m produces the most optimum conditions for the best TOPURBAN v. 1 performance. TOPURBAN v. 1 was later modified to create TOPURBAN v. 2 which better accounted for the storage in urban areas that was not considered in version 1. The new version added an additional calibration parameter and was tested on 6 data series in total. TOPURBAN v. 2 increased Nash and Sutcliffe Efficiency by anywhere from 2% to 8%. This increase proves that TOPURBAN v. 2 is a suitable model for combining urban areas into a hillslope hydrology scheme. TOPURBAN v. 2 was compared to the conventional Hortonian-Flow model QualHYMO, on all 6 continuous series, on two single events, and on the regional storm. TOPURBAN v. 2 out-performed QualHYMO in the single event tests and in the continuous series simulations by anywhere from 20% - 80% in Nash and Stutcliffe Efficiency. Estimates of peak flow rate for the regional storm were within roughly 35% of the estimate provided by MacLaren Plansearch Ltd. in the Spencer Creek Watershed Study that included the Ancaster Creek Catchment.

abstract: Doctor of Philosophy (PhD)


title: Spectroscopy of Disordered Materials

contributor:
Walton, D.
Physics

subject: Physics Physics

abstract:
Mixed crystals of (KBr)₁_ᵪ(KCN)ᵪ show a complicated structural behavior at low temperatures which includes an intriguing orientational glass state. Better understanding of these relatively simple disordered systems may improve our understanding of the glassy state in general.

We have used the Brillouin spectroscopy to measure the acoustic phonon properties in the KBr-KCN alloys. All aspects of the spectra, such as Brillouin shift, linewidth and intensity, were found to qualitatively agree with Michel's microscopic theory. From the frequency and the width of the acoustic phonon, we determined the reorientation rate of CN‾ quadrupoles as a function of temperature, which can be described by an Arrhenius law.

Quasi-elastic light scattering in (KBr)₁_ᵪ(KCN)ᵪ was measured using a high resolution tandem Fabry-Perot interferometer. The width of the quasi-elastic peak was found to have a strong temperature dependence. We suggest that this peak is dynamic in origin and is related to the reorientation of the cyanide dipoles.

We observed the appearance of symmetry forbidden scattering peaks in the Brillouin spectra of (KBr)₁_ᵪ(KCN)ᵪ in the presence of a uniaxial stress. This effect can be explained as a stress-induced birefringence altering the polarization state of the scattering light. There are no observable changes in Brillouin shift and width induced by such a stress.

The dielectric loss and capacitance of an x=0.5 sample was determined using a high precision bridge. Only one loss peak appears at "30 K in the temperature interval from 1.2 K to 294 K, which indicates that there is no coupling between quadrupole and dipole moments at around quadrupolar freezing temperature ("80 K).

A calorimetric technique was used to investigate thermal properties of (KBr)₀.₅(KCN)₀.₅ at T≤1 K. The specific heat of the sample is in good agreement with reported values. Samples which have undergone different thermal treatments show different heat drift behavior. Analysis of the time-decay of temperature after application of a heat pulse reveals that the decay curve follows a stretched exponential form.

Finally, the acoustic sound wave in propylene glycol was studied using a Brillouin scattering technique. The relaxation rates obtained in the gigahertz frequency range were compared with the low frequency specific heat data in terms of the Vogel-Tamman-Fulcher law and the scaling law. The latter was predicted by recent hydrodynamic theories for the glass transition.

abstract: Doctor of Philosophy (PhD)


title: A Study of the Effect of Element Shape on the Accuracy of Various 2D Finite Element Formulations

contributor:
Weaver, D.S.
Mechanical Engineering

abstract: Linear Isoparametric elements and elements based on the Constant Strain Triangle are developed and incorporated into a computer program, for two dimensional stress analysis on mini computers. These elements are compared at element level using the Weighted Eigenvalue method and in assemblage using sensitivity analysis. Further, a method of predicting results based on the data generated during the comparisons at the element level is also presented. As an application of the computer program, analysis of a porcelain insulator is also included.

abstract: Master of Engineering (ME)


title: Open Architecture Control For Intelligent Machining Systems

contributor:
Elbestawi, M. A.
Mechanical Engineering

abstract: The purpose of this study is to examine the role that Open Architecture Control concepts have in the application of Intelligent Machining Systems. Open Architecture Control is a relatively new field whose original intent was based on the use of "Open System" computer science concepts in the development of integrated manufacturing systems. Various manifestations of Open Architecture Control systems has been published in the open literature however, in many ways the original intent of the idea has been often obfuscated by the sometimes dissimilar interests of the engineering, computer science, academic and commercial realms involved. Intelligent Machining Systems refers to application of sensing, monitoring and control technologies to machining processes with the intent of: - improving the economic performance of machining systems, - controlling the processes involved in a comprehensive manner. Consequently, such systems represent an integration of technologies which individually address only a limited part of the overall potential for economic gain. The use of "higher level" information and control functions is a common element in Intelligent Machining Systems. These may include components of Artificial Intelligence, process planning, and supervisory control technologies. The need for a high level of integration in Intelligent Machining Systems (IMS) has presented a difficulty for their practical application. Open Architecture Control (OAC) address the integration problem directly and, if the proper Open Systems issues are well considered, can enable IMS technology for commercial use. The OAC system developed in this work does address Open Systems concepts, and has been designed with consideration for the needs of IMS's. This has been achieved through the formulation and implementation of an IMS on the designed OAC. Technologies such as process sensing, monitoring and control, in addition to planning, simulation and supervisory control have been tested and verified with the OAC for an application to turning a CNC turret lathe.

abstract: Doctor of Philosophy (PhD)


title: The Timing of Human Menarche

contributor:
Daly, M.
Psychology

subject: Psychology Psychology

abstract: Like other aspects of female physiology, menarche is senstlive to aspects of the spcial and physical environment. Two surveys, involving 1,314 Ontario residents, were distributed to examine the relationship between family composition and the timing of human menarche. The average menarcheal age was 13.00 years and is concordent with previous estimates for central Canada. Menarche occurred most frequently in the spring and summer months and occurred later in women born ofter 1960 than in those born prior to this date. Most socioeconomic factors did not significantly influence the timing of menarche, but weight per height was marginally and negatively correlated with menarcheal age. Total score on a life events inventory, a measure of stress, was negatively and significantly correlated with the age at menarche. Menarcheal age was positively related to the age at which a girl began dating. The most striking finding was that girls who experienced father absence before menarche matured on average 4.5 months earlier than girls who lived with both parents continuously. Moreover, girls who had experienced father absence before ten years of age and because of divorce matured 5-6 months earlier than girls growing up with both parents. Absence of the mother and number of brothers end sisters did not appear to be related to the timing of menarche. A significant correlation existed between mothers' and daughters' ages at menarche. The mothers of father-absent girls tended to be early maturers, dated early, had early first births and reported more negative views of men than did the mothers of father-present girls. Heredity and psychological stress may largely account for the early age at menarche observed in father--absent girls, but physical exposure to a father and other psychological factors could elso be involved.

abstract: Doctor of Philosophy (PhD)