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Fluidized bed claus reactor studiesBonsu, Alexander Karikari January 1981 (has links)
Fluidized bed reactor studies were performed on the Claus reaction, ie. 2H₂S + S0₂<->3/n S[sub=n]n + 2H₂0. The basic objective was to determine whether the performance of the Claus process could be improved by replacing conventional fixed bed reactors with fluidized bed reactors.
A computational procedure was developed which, unlike previous methods, does not require the user to specify the initial values for the iterative solution of the equilibrium equations. It is therefore possible to achieve, consistently, significant reductions in computer time and cost. The computer programme was used to simulate various idealized Claus plants. The results of the equilibrium calculations indicated that, for feed gases consisting of pure H₂S, sulphur conversions in excess of 99% are attainable by using a Claus furnace and two fluidized bed reactors in series.
To substantiate the theoretical predictions, experimental studies were performed using a single fluidized bed reactor (0.1 m ID). The effects of temperature (150 - 300°C), flow rates (15 - 30 1/min), feed composition (0.06<H₂S<18%, 0.03<S0₂<9%, 73<N₂<99.91%) and bed height (0.12, 0.25 m) on the sulphur conversion were examined. The experimental results showed the same general trends as the theoretical predictions. However, the measured
sulphur conversions exceed the theoretical values by up to 8%. Reasons for these discrepancies are discussed.
Based on the theoretical and experimental studies, fluidized bed reactors appear to be technically superior to the conventional fixed bed devices. However, a proper commercial evaluation has to await longer term studies with larger fluidized beds. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate
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Epistemic reasoning and adolescent egocentrism among adolescent boys with behavioral disorders and their peers without behavioral disordersBeaudoin, Kathleen Mary 05 1900 (has links)
A number of investigations have been conducted to examine social cognition
and psychopathology among adolescents, yet little is known about the social cognitive
reasoning of adolescents identified as having severe behavioral disorders. The
purpose of the present study was to explore the social cognitive reasoning of
adolescent boys with behavioral disorders in comparison to their peers without
behavioral disorders. Group differences were examined with respect to epistemic
reasoning and the dimensions of adolescent egocentrism. In addition, the relation
between social cognition and social relationships was investigated. Finally, the
relation between social cognition and psychopathology was explored.
Thirty-one adolescent boys with behavioral disorders and 32 of their peers
without behavioral disorders (matched forage, race, and SES) participated in the
study. All participants were individually administered measures designed to assess
epistemic reasoning, imaginary audience and personal fable ideation (i.e.,
invulnerability, omnipotence, personal uniqueness), and personal-intimacy and groupintegration
with peers and family. In addition, boys with behavioral disorders
completed a measure of internalizing, externalizing, and total problem behaviors.
Teacher-ratings of problem behaviors were also completed for each participant in the
study.
Results revealed that adolescent boys with behavioral disorders were lower in
epistemic reasoning than were adolescent boys without behavioral disorders. Groups
were not found to differ with respect to imaginary audience or personal fable ideation.
For boys with behavioral disorders, no relation was found between social cognition
and social relationships. In contrast, for boys without behavioral disorders, personal
uniqueness was negatively related to group-integration with peers and omnipotence
was positively related to group-integration with family. Social cognitive reasoning was
found to predict self-reported problem behaviors for boys with behavioral disorders
and teacher-re ported problem behaviors for boys without behavioral disorders.
Overall, these results suggest the importance of epistemic reasoning in understanding
the relation between social cognition and psychopathology. / Education, Faculty of / Educational and Counselling Psychology, and Special Education (ECPS), Department of / Graduate
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Managing MIS project failures : a crisis management perspectiveIacovou, Charalambos L. 05 1900 (has links)
This study describes a conceptual framework that portrays information system project
failures as organizational crises. The main assumption of this study is that such failures
will invariably happen and thus there is a need to make them less costly and more
beneficial to organizations. To identify the behaviors and factors that influence an
organization's ability to effectively manage a project failure, this dissertation reviews the
crisis management literature. Based on this review, a three-stage model is formulated. To
understand the mechanisms underlying this model, a number of hypotheses (which are
informed by a number of related organizational behavior areas) are generated. These
hypotheses focus on three key crisis management factors: the organization's ability to
promptly detect an impeding failure, its capacity to manage the failure's impacts, and its
propensity to learn from it. To empirically assess the validity of the conceptual model,
three case studies of Canadian public organizations were conducted. The empirical
findings provide strong support to the model's conjectures and indicate that project failures
generate several crisis-related behaviors and responses. More specifically, the findings
suggest that an organization's proactive preparation for a failure can have a significant
moderating effect on its impact. However, the findings clearly show that an organization's
ability to promptly detect (and prepare for) a failure is impeded by behaviors that are
motivated by escalation of commitment. Such behaviors lead to a prolonged pre-crisis
denial period and have a suppressing effect on whistle-blowing, which is pursued as a
denial-curtailing strategy by non-management participants. The empirical findings
describe both operational and legitimacy tactics used by organizations to cope with the
aftermath of a project failure and indicate that credibility restoration is a significant
concern during large crises. Finally, the empirical evidence indicates that organizational
learning and adaptation are more likely to follow major project failures than less
significant ones. This contradicts threat-rigidity arguments and provides support to the
failure-induced learning theory. / Business, Sauder School of / Graduate
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Children’s metapragmatic knowledge and intensity of second language as a medium of instruction in the intermediate years of a French immersion programTakakuwa, Mitsunori 11 1900 (has links)
Compared to grammatical knowledge of language (what to use), the ability to use
language appropriately depending on a context (how to use) is termed linguistic pragmatic
knowledge. Throughout the elementary school years children developmentally not only acquire
pragmatic knowledge but also increase their explicit grasp of pragmatic knowledge. This is
termed metapragmatic knowledge. It includes the ability to infer meanings that are not expressed
literally. In nonliteral uses of language, the speaker means something different from what is said.
Among such nonliteral uses of language are indirect requests and irony.
As children's metapragmatic knowledge has a positive relationship with their literate
proficiency, on which success in school depends, children can benefit from the development of
their metapragmatic knowledge in their academic achievement. The study of bilingualism has
shown that bilingualism has a positive effect on children's metalinguistic development. Can
metapragmatic knowledge be enhanced by increasing exposure to a second language (L2)?
Bilingual pupils were given two tasks in which the children's levels of metapragmatic
knowledge were investigated. The measure of metapragmatic knowledge consisted of two
assessments: (a) understanding of indirect requests, and (b) understanding of irony. Participants
listened to eight short stories in which brief interactions were presented in a multimedia,
computer-based format. After each story, participants were asked a set of questions to probe
subjects' attributions of the speaker's communicative intent and hearer's interpretation.
L2 intensity was positively associated with metapragmatic knowledge measured by
comprehension of requests. Conversely, the association between L2 intensity and metapragmatic
knowledge measured by comprehension of irony was not necessarily positive. Those who scored
higher had positive relationship between L2 intensity and their metapragmatic knowledge
whereas those who scored lower had negative relationship between L2 intensity and their
metapragmatic knowledge.
In summary, L2 intensity is not always positively associated with any type of
metapragmatic knowledge. This suggests that a larger amount of exposure to L2 is not
necessarily beneficial to children's development of metapragmatic knowledge. Therefore, it is
important to consider the levels of children's metapragmatic knowledge when planning an
increase of exposure to L2 instruction. / Education, Faculty of / Language and Literacy Education (LLED), Department of / Graduate
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Die gebruik van die gevallestudiemetode in die ontwikkeling van strategiese bestuursvaardighede : 'n teoretiese besinningLessing, Izak Jacobus 04 September 2012 (has links)
M.Comm. / The case method can serve as an instrument to improve the learner's skills across a wide spectrum. It is extremely important that the theoretical background of the learner be focused in such a way to be of practical use for the embryo-manager. The correct use of the case method is a powerful tool for the developer, but incorrectly used, it can have negative results. The case method relies on the learning-by-doing principle. The learner does not merely hear or read about situations within the work place, but experiences analysis and problem solving first-hand during the class discussion.The facilitator ought not use the first case study he lays his hands on when planning a class discussion. Cases must be selected with great care, to suit the learning objectives and must take into account the learners' level of knowledge and development. The use of a standardised classification matrix can assist the facilitator to identify the appropriate case study. Before a learner can be expected to analyse and discuss cases, he/she should receive the necessary guidance beforehand. The use of a set of generic guidelines in case analysis, should enable the learner to solve virtually any case he/she is confronted with. As the learner gains experience in case analysis, the generic guidelines can be adapted to conform with the learners specific needs as well as with the specific nature of the case under discussion. Research regarding the use of the case method to develop managerial skills is still totally inadequate.
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Time-place learningThorpe, Christina Marie 05 1900 (has links)
The ability to learn spatiotemporal characteristics of biologically significant
events is advantageous for an animal and is known as time-place learning (TPL).
Gallistel (1990) proposed an influential theory positing that whenever a biologically
significant event occurred, a memory code was automatically formed, encoding the
nature of the event, and the time and place in which it occurred. When the animal is later
faced with a biological need it could consult these memory codes and determine when
and where that need had been met in the past. This information could be used to guide
current behaviour. Importantly, Gallistel theorized that the encoding of the
spatiotemporal characteristics of an event into a tripartite code was an automatic process.
Despite the appealing power and simplicity of Gallistel's theory, I have provided
arguments suggesting that it has serious limitations. Perhaps the most damaging evidence
against this theory is the reluctance of rats to demonstrate daily TPL (i.e., events that vary
in location depending on time of day). Widman, Gordon, and Timberlake (2000) argue
that for TPL to occur the response cost for incorrect decisions must be high. While this
hypothesis is unable to explain the inconsistencies in TPL, it does highlight the fact that
animals do not automatically store time-place-event information as a tripartite code. If
they did, it would not make sense for them to ignore such information in some tasks.
I have provided an alternative hypothesis that states that whenever a biologically
significant event occurs two bipartite memory codes (time-event and place-event) are
automatically formed. Only under some conditions, perhaps those with high response
cost, do animals form tripartite codes. For this reason, rats often have difficulty learning a
TPL task; although rats easily learn a place preference for those places that provide
reinforcement (place-event), and easily learn a go/no-go discrimination (time-event). This
thesis provides data from both the daily and interval TPL realms supporting the proposed
theory of bipartite codes.
Although rats do not readily learn daily TPL tasks, they do demonstrate
knowledge of interval TPL under a variety of conditions designed to enhance the
ecological validity of the task. The properties of interval TPL are discussed. / Arts, Faculty of / Psychology, Department of / Graduate
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Cognitive and behavioural responses to illness information in health anxietyHadjistavropoulos, Heather Deanne 05 1900 (has links)
A cognitive-behavioural theory (CBT) has been put forth to explain hypochondriasis and less extreme
forms of health anxiety (Warwick & Salkovskis, 1990). The extent to which less extreme forms of health anxiety
are relevant for understanding illness behaviour remains unclear, however. Further, the independence of health
anxiety from a more general construct of negative affectivity, as well as response styles is not known. The CBT
of health anxiety predicts that in response to illness information health anxious individuals will show a
characteristic cognitive (e.g., attend to and misinterpret information) and behavioural (e.g., avoidance and
reassurance seeking) response. Although the predictions are supported by clinical observations, rigorous and
systematic contrasts of health anxious and non-health anxious individuals to the same objective health related
information have not yet been carried out. Further, there are a number of additional issues that need to be
clarified with respect to the theory, including: (a) Are there additional cognitive and behavioural responses
involved in health anxiety not predicted by the CBT?; (b) Are health anxious individuals deficient in there use of
certain adaptive responses to illness information?; and (c) Are the cognitive and behavioural responses shown by
health anxious individuals moderated under certain circumstances?
In the present study, students scoring either within normal or nonclinically high ranges on a measure of
health anxiety underwent a physiological test ostensibly examining risk for medical complications and were
randomly assigned to receive positive, negative, or ambiguous test results. They then underwent a cold pressor
task ostensibly to examine physiological activity and were asked questions tapping their responses to the
diagnostic information and painful procedure. They were also judged for facial expressiveness.
Unmistakable support was found for a dysfunctional cognitive (e.g., negative interpretational focus) and
behavioural (e.g., reassurance seeking) response style among health anxious individuals. Little support was
found for either cognitive or behavioural avoidance in health anxiety. Not anticipated by the CBT, as time went
on health anxious individuals became more expressive of their pain; this may have important implications, since
increased expressiveness could result in an increase in the felt emotional experience. Adding to the CBT,
evidence was found to suggest that health anxious individuals may have a deficit or be deficient in their use of a
positive concrete somatic monitoring strategy. Finally, the results suggested that there are statistically and
clinically significant differences among nonclinically health anxious individuals and normals that can not be
accounted for by differences in negative affectivity or response styles. / Arts, Faculty of / Psychology, Department of / Graduate
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The effect of age, breed, days open, stage of lactation and pregnancy upon daily body weight and milk weight in lactation dairy cattleYegezu, Zegeye January 1977 (has links)
The effect of age, breed, days open at conception, stage of lactation and pregnancy upon daily body weight and milk weight in lactating dairy cattle were studied. The cattle used in the study were those of the University of British Columbia Research Farm at Oyster River, B.C.
76 Holstein and 60 Holstein X Ayrshire crossbred milking cows at different stages of lactation and both either open or pregnant, were used in this study. The study was carried out during the months of May and June of 1975. The procedure involved weighing the animals daily after the afternoon milking and recording the daily milk yield along with the weight of each cow.
The cows were classified into three groups, namely All, Open and Pregnant, the first group being a combination of the last two. For All and Open cows, the effect of age, breed, age by breed and number of days in milk on body weight and milk weight were investigated. For the Pregnant cows, the effect of age, breed, number of days open at conception, age by breed, age by number of days open at conception, breed by number of days open at conception and number of days pregnant on body weight and milk weight were investigated. Using the number of days open at conception as a dependent variable, the effect of age, breed and age by breed were investigated.
The results showed that among All, Open and Pregnant cow groups, the older cows were significantly (P <0.05) heavier and were producing significantly (P <0.05) more milk than the younger cows. Age accounted for 0.9%, 1.5% and 0.8% of the body weight variation and for 0.1%, 0.5% and 1.3% of the milk weight variation in All, Open and Pregnant cow groups respectively. Among the All, Open and Pregnant groups, the older cows weighed more by 143.22, 133.12 and 125.07 lbs and produced 3.72, 6.98 and 12.14 lbs more milk per day respectively than the younger cows.
Among All, Open and Pregnant groups, a significant breed effect (P <0.05) on body weight and milk weight was observed. In the three groups, breed accounted for 2.3%, 3.8% and 0.1% of the body weight variation and for 0.1%, 0.3% and 0.6% of the milk weight variation respectively. Among All and the Open cow groups the Hoi steins were heavier by 223.00 and 214.04 lbs and were respectively producing 5.20 and 5.26 lbs more milk daily than the crossbreds. Among the Pregnant cow group the Hoi steins were lighter by 49.33 lbs and produced 7.74 lbs less milk daily than the crossbreds.
The number of days open at conception was a significant source of variation (P <0.05) affecting body weight but not milk weight in the Pregnant cow group. It accounted for 1.3% of the body weight variation. Those cows who stayed open longer than 123 days were heavier by 159.21 lbs than those who became pregnant earlier or on day 123 after calving.
Age by breed for the All cow group was significant (P <0.05), accounting for 0.1% of the body weight variation. This interaction was not significant for body weight of the other two groups and for milk weight of all the three groups.
Age by number of days open at conception was significant (P <0.05) for the Pregnant cow group milk weight and accounted for 1.2% of the variation. This interaction was not significant for body weight. Breed by number of days open at conception was not significant for the Pregnant cow group body weight and milk weight.
Number of days in milk for All and Open cows had a significant (P <0.05) effect on both body weight and milk weight. It accounted for 10.2% and 2.9% of the variation in body weight and 35.6% and 18.4% of the variation in milk weight in All and Open cow groups respectively.
In the Pregnant cow group, the number of days pregnant resulted in significant (P <0.05) effect on both body weight and milk weight. It accounted for 30.8% and 61.4% of the body weight and milk weight variation respectively.
When number of days open at conception was used as a dependent variable, age, breed, and age by breed showed a significant (P <0.05) effect in the pregnant cow group. Age, breed, and age by breed accounted for 0.3%, 0.4% and 0.9% of the variation respectively. / Land and Food Systems, Faculty of / Graduate
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The influence of intraorganizational conflict upon the behaviour of a collective bargaining teamStorey, Gordon Douglas January 1978 (has links)
This thesis reports theory development and explorative field observation of potential effects of conflict occurring within a collective bargaining team. From the theoretical bases of Walton and McKersie's (1965) intraorganizational conflict (IOC) concept and Pondy's (1967) process model of conflict, a model of bargaining team IOC is developed. The model partitions bargaining team IOC into functional and dysfunctional subsets. Seven propositions related to the effects of dysfunctional IOC are developed from conflict and decision making literature. These propositions are concerned with the effects of dysfunctional IOC on participation of team members, rule breaking behavior, time delays, and decision styles.
Operational definitions and tests for dysfunctional IOC are developed using Filley's (1975) five item definition of conflict and seven item win-lose, lose-lose, conflict responses. A participant/observer quasi-case analysis of an actual collective bargaining team experience is the basis for data generation.
Many of the propositions are supported iii the observed bargaining team environment. While the single case methodology prevents generalized conclusions regarding the effects of dysfunctional IOC, the findings tentatively suggest there may be considerable practical payoffs for extending this research area.
The field experience provides some additional research insights regarding the dynamic variable of dysfunctional IOC. In this study, dysfunctional bargaining team IOC is observed as a few recurring issue-related problems flowing throughout the bargaining team interactions. Implications of this study regarding future research on IOC in a bargaining team are suggested. / Business, Sauder School of / Graduate
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The snowmelt hydrology of a small alpine watershedJordan, Robert Peter January 1978 (has links)
A study of the mass and energy balance of a small alpine watershed was conducted in the summer of 1976, with the aim of applying snow hydrology theory at a watershed scale in a remote environment. The field area is in the Coast Mountains near Bralorne, B.C. The study concentrates on the measurement of snow ablation, the movement of meltwater within the snowpack, the generation of stream runoff during and following snowmelt, and the energy balance at the snow surface.
Standard methods for measuring snow ablation, used in the fields of glaciology and snow surveying, are analysed in terms of their accuracy and precision, and the sampling densities required for their application. Simple field instrumentation is used to study the movement of meltwater in the snowpack, and this is analysed in terms of the theory of flow through a porous medium. The movement of meltwater through the snow is found to be the most important process affecting the shape and timing of the stream hydrograph. The movement of water along the base of the snowpack and through the soil also has an influence on the shape of the hydrograph. In the alpine meadow environment studied, saturated soil and ice covering ground beneath the snow contribute to a rapid stream response.
A water balance is calculated for the watershed, based on measurement of stream discharge, snow ablation, and precipitation, and on climatological estimates of evaporation. An energy balance for the season is also calculated, supported by microclimatological measurements for part of the season. Radiation is found to contribute 90% of the energy required for snowmelt, and a simple model for the calculation of net radiation from solar radiation is developed. Empirical methods are found to be suitable for the calculation of turbulent energy transfer over snow.
Some observations are made of the water balance in the late summer, and these indicate that water stored in the soil during snowmelt is important in maintaining streamflow later in the season. / Arts, Faculty of / Geography, Department of / Graduate
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