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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Simulation-based fault propagation analysis of process industry using process variable interaction analysis

Hosseini, Amir Hossein 01 January 2013 (has links)
There are increasing safety concerns in chemical and petrochemical process industry. The huge explosion of Nowruz oil Field platform that happened in Persian gulf-IRAN at 1983, along with other disastrous events have effected chemical industrial renaissance and led to high demand to enhance safety. Oil and chemical Industries involve complex processes and handle hazardous materials that may potentially cause catastrophic consequences in terms of human losses, injuries, asset lost and environmental stresses. One main reason of such catastrophic events is the lack of effective control and monitoring approaches that are required to achieve successful fault diagnosis and accurate hazard identification. Currently, there are aggressive worldwide efforts to propose an effective, robust, and high accuracy fault propagation analysis and monitoring techniques to prevent undesired events at early stages prior to their occurrence. Among these requirements is the development of an intelligent and automated control and monitoring system to first diagnose faulty equipment and process variable deviations, and then identify hazards associated with faults and deviations. Research into safety and control issues become high priority in all aspects. To support these needs, predictive control and intelligent monitoring system is under study and development at the Energy Safety and Control Laboratory (ESCL) – University of Ontario Institute of Technology (UOIT). The purpose of this research is to present a real time fault propagation analysis method for chemical / petrochemical process industry through fault semantic network (FSN) using accurate process variable interactions (PV-PV interactions). The effectiveness, feasibility, and robustness of the proposed method are demonstrated on simulated data emanating from a well-known Tennessee Eastman (TE) chemical process. Unlike most existing probabilistic approaches, fault propagation analysis module classifies faults and identifies faulty equipment and deviations according to obtained data from the underlying processes. It is an expert system that identifies corresponding causes and consequences and links them together. FSN is an integrated framework that is used to link fault propagation scenarios qualitatively and quantitatively. Probability and fuzzy rules are used for reasoning causes and consequences and tuning FSN. / UOIT
112

Elucidating the Mechanisms of Transposable Elements using Experimental and Bioinformatic Approaches: The hAT Superfamily of Transposable Elements in the Genome of Aedes aegypti and TE Displayer

Rooke, Rebecca 19 December 2011 (has links)
Transposable elements (TEs) are found in nearly all eukaryotic genomes and are a major driving force of genome evolution. The hAT superfamily of TEs are found in a variety of organisms, including plants, fungi, insects and animals. To date, only 14 hAT TEs in the Aedes aegypti genome have been annotated as having a hAT transposase coding sequence. In this study, extensive bioinformatic approaches have been employed to find hAT TEs that encode transposases in the A. aegypti genome. A total of six newly-identified TEs belonging to the hAT superfamily were discovered in the A. aegypti genome. Furthermore, a computer program called TE Displayer was developed to analyze TEs in genome sequences. TE Displayer detects TE-derived polymorphisms in genome datasets and presents the results on a virtual gel image. TE Displayer enables researchers to compare TE profiles in silico and provides a reference profile for experimental analyses.
113

Elucidating the Mechanisms of Transposable Elements using Experimental and Bioinformatic Approaches: The hAT Superfamily of Transposable Elements in the Genome of Aedes aegypti and TE Displayer

Rooke, Rebecca 19 December 2011 (has links)
Transposable elements (TEs) are found in nearly all eukaryotic genomes and are a major driving force of genome evolution. The hAT superfamily of TEs are found in a variety of organisms, including plants, fungi, insects and animals. To date, only 14 hAT TEs in the Aedes aegypti genome have been annotated as having a hAT transposase coding sequence. In this study, extensive bioinformatic approaches have been employed to find hAT TEs that encode transposases in the A. aegypti genome. A total of six newly-identified TEs belonging to the hAT superfamily were discovered in the A. aegypti genome. Furthermore, a computer program called TE Displayer was developed to analyze TEs in genome sequences. TE Displayer detects TE-derived polymorphisms in genome datasets and presents the results on a virtual gel image. TE Displayer enables researchers to compare TE profiles in silico and provides a reference profile for experimental analyses.
114

A Traffic Engineering Approach to Differentiated Multicast Services over MPLS Networks

Barabas, Toni 07 March 2012 (has links)
Currently, a viable solution to provide multicast provision over a multiprotocol label switch with traffic engineering (MPLS-TE) domain is unavailable because of the missing link able to couple multicast traffic distribution with an MPLS-TE enabled network. This is due to the limited or less research investigation that was done in this area. Most of the investigation methods tackle the problem individually such as deploying internet protocol (IP) multicast in a plain network or MPLS domain but without considering a combination of both technologies that is aware of differentiated services requirements. This thesis presents an alternative solution for the multicast differentiated services provision problem over a MPLS-TE enabled network. The approach is exposed and analyzed through a practical solution that was developed within a network simulation environment. The research presented in this thesis orchestrates the already available technologies offered by the multicast protocols suite and differentiated services (DiffServ) aware MPLS-TE that allows applying separately the constraint-based routing and admission control to different classes of services. The novelty and solution of this thesis relies on using MPLS constraint-based routing concepts (e.g.traffic trunks) in order to solve TE issues revealed during multicast traffic distribution.
115

Electrochemical Deposition of Bismuth Telluride and Antimony Telluride Thin Films for Micro TE-cooler Applications

Li, Ming-chan 13 July 2006 (has links)
¡@¡@¡@¡@¡@¡@¡@¡@¡@¡@¡@¡@¡@Abstract This paper presents an integrated batch-produced (Bi, Sb)2Te3 micro thermoelectric cooler(£g-TEC) fabricated by electrochemical MEMS technology. To optimize the thermal conductivity of (Bi, Sb)2Te3 thin layers, a cathode with tunable rotary speed has been designed in the electroplating system to well control the thin film deposition rate and uniformity.The column-type micro thermoelectric thin films fabricated using electrochemical-deposited and patterned using photolithography processes. The thermoelectric thin films made of N-type Bi2Te3 and P-type Sb2Te3 with an average thickness of 5£gm, are connected using Cr/Au layers at the hot junctions and cold junctions. The measured Seebeck coefficient and electrical resistivity of the thermoelectric thin films,are -52£gV/K and 2.52¡Ñ10-5£[m(N-type, power factor of 0.11mW/K2m),and 71£gV/K and 1.91¡Ñ10-5£[m( P-type, power factor of 0.26mW/K2m) after annealing at 250¢J.Under the circumstances that voltage of 2-5 volts is driven, the upper and lower levels electrode shows tentatively that there is 0.7¢Jof difference in temperature.
116

A Comparison of Origins and Influences in the Music of Vaughn Williams and Britten through Analysis of Their Festival Te Deums

Jensen, Joni January 2005 (has links)
Ralph Vaughan Williams and Benjamin Britten were two of the most prominent and popular composers in England in the first half of the twentieth century; however, their musical styles represent two different schools of thought, pastoralism and modernism. Despite their differences, they had much in common. They attended the same school; were heirs of a movement to promote English music, the English Musical Renaissance; and greatly admired their predecessor Henry Purcell. This document investigates how these two composers formulated diverse compositional styles even though they shared a common musical heritage.The investigation in this document is two-part. First, the investigation depicts the origin and formulation of both composers' styles through a discussion and comparison of their musical backgrounds, teachers, influences, and ideals. This discussion includes information on their personal training and ideas, as well as influential movements, composers, and teachers. The second portion includes analysis and comparison of Vaughan Williams' and Britten's Festival Te Deums. The document includes a discussion of the origin of the Te Deum text and history of musical settings. Specific elements of the Festival Te Deums are discussed, compared, and traced to possible origins of influence in each composer's heritage. This document includes an analysis of Purcell's Te Deum in comparison to the Vaughan Williams and Britten settings as a demonstration of the affects of a common influence on their music.The influences and ideals of each composer clearly manifest themselves in their respective Festival Te Deums. The analysis confirms there are obvious differences in their respective musical ideas; however, the effects of similar influences on their musical styles are not always similar. Although Vaughan Williams and Britten followed the principles of the English Musical Renaissance and emulated Purcell, each composer was so distinct in his musical interpretation that it is difficult to recognize the similar influences in the music itself. In this way, both remained committed to their heritage, but each developed a unique musical voice.
117

Atuatanga: Holding Te Karaitianatanga and Te Māoritanga Together Going Forward.

Hollis, Jubilee Turi January 2013 (has links)
This thesis sets out to provide the background to the development of Atuatanga and to clarify its meaning and its whakapapa in Te Māoritanga and Te Karaitianatanga. Although it has been taught as Māori theology in Tikanga Māori of the Anglican Church in Aotearoa, New Zealand and Polynesia, this thesis argues that is includes theology and more: it is a way of living that critically analyses all the attributes of te Atua and endeavours to live those reflections in the world in order
118

Conceptualising Wairuatanga: Rituals, Relevance and Realities for teachers

Foster, Winnie Gipsy January 2009 (has links)
This research project was based on the complexities and conceptualising forms of wairuatanga and their implications for teaching and learning in New Zealand mainstream schools. As a relatively new study for research the project explored wairuatanga through the life and work experiences of three Māori teachers from education centres around New Zealand. Wairuatanga permeated through the life and teaching of the participants who all expressed their own sense of wairuatanga in different ways. The cognisance of mātauranga Māori, tikanga Māori and insights into te ao Māori were identified and explored thus taking into account the various ways in which the three participants extended the parameters of existing knowledge of wairuatanga and how they promoted and created a climate within their own teaching context that fostered the natural inclusion of wairuatanga. The findings will assist current teachers and others to develop an understanding and appreciation of the different forms of wairuatanga that may assist them to apply this value to their own classroom practice. It is hoped that the findings will also help to inform teaching practices with respect to teaching and learning not only for Māori children but for all children in New Zealand mainstream schools.
119

The development of the Traffic Conflicts Technique : an approach to the study of road accidents

Lightburn, Angela D. C. January 1984 (has links)
A practical and reliable alternative or supplement to injury accident data is necessary to diagnose dangerous sites and evaluate remedial measures because available accident data is scarce, is lacking in detail about the events preceding the accident and it takes a long time to accumulate statistically reliable data. The most favoured alternative is the Traffic Conflicts Technique which satisfies most of the requirements of a supplementary measure, but has so far only been successfully validated for rural dual carriageway intersections (Spicer, 1973). To establish the technique it is necessary a) to ensure that the subjective judgements on which it is based are reliable, b) to develop the best methods of recording conflicts, and of training and selecting observers, and then c) to test the validity of the best available technique. The main part of this thesis reports three studies aimed at each one of these issues. In the first study intra observer reliability tested on filmed material varied between rs = 0.30 and 0.91 (0.65 overall for N = 42), but poor observers could be identified. By selecting the best observers an overall reliability figure of up to 0.88 could be obtained. Reliable observers remained reliable or even improved slightly on the second testing. These reliable observers also showed good agreement with expert judges who had viewed the film many times, and by selection a correlation with the criterion value of up to 0.83 could be obtained. In the second study a new recording method was developed, incorporating factors that experienced observers used to differentiate the grades of severity currently in use. This helped observers by defining the criteria for detection and grading of a conflict more objectively. This increased the overall intra observer reliability from 0.73 to 0.80, and agreement with the criterion values from 0.66 to 0.76. Transfer from laboratory to field led to a drop in the numbers of conflicts reported. From these studies and a survey of the requirements of local authority accident investigation units, a manual and training package was developed giving guidance on training and selecting observers for the purpose of obtaining reliable conflict data, such as that required for validating the technique. In the third study this package was validated in a study of a sample of eight urban T-junctions. Again the best observers were selected and found to have an overall reliability of 0.88. It was found that, when rear end conflicts were excluded (on the grounds that they led to so few reported injury accidents while occurring in large numbers), there was a high correlation between accidents per vehicle and conflicts per vehicle (rs = 0.79, p<0.025), accounting for 62% of the variance. This compares very favourably with the maximum possible percentage (77%) which could be expected given the relaibility (rs = 0.88) of the observers. Although a validity correlation of 0.79 is very satisfactory and the method of obtaining the data is reasonably economical, an attempt was made to find a still more economical alternative to accident statistics. The most obvious of these are subjective judgements or a combination of these with traffic flow. Traffic flow data for different manoeuvres at each of the eight T-junction sites were obtained and various groups of people were asked to judge the subjective risk of these sites from scale maps and photographs or directly on-site. Judgements from maps and photographs tended to be negatively correlated with accidents. The best subjective estimate (driving instructors judging on-site) correlated 0.44. An attempt to improve on these by combining the traffic flows and judged risk of the different manoeuvres at each site failed to produce a higher correlation. None of these correlations were significant, but the failure of any one of several different corrrelations to be higher than 0.46 suggests very strongly that these simpler methods are very unlikely to have the validity of the full conflicts technique. However, the present study has validated the Traffic Conflicts Technique only for urban T-junctions (the commonest of all accident sites). It could, therefore, only be used for evaluating the effects of small changes in the layout of such junctions. It could be used to evaluate more radical changes eg. T-junction converted to a mini roundabout, provided the conflict to accident ratios of the different layouts were known. In this study the conflict to accident ratio was 125:1 for vehicles turning right out of the minor road. For the T-junctions as a whole it was 275:1 while Older and Spicer(1976) found a ratio of 2000:1 for rural dual carriageway intersections. By obtaining more information of this kind, the utility of the Traffic Conflicts Technique could be greatly extended.
120

A Traffic Engineering Approach to Differentiated Multicast Services over MPLS Networks

Barabas, Toni 07 March 2012 (has links)
Currently, a viable solution to provide multicast provision over a multiprotocol label switch with traffic engineering (MPLS-TE) domain is unavailable because of the missing link able to couple multicast traffic distribution with an MPLS-TE enabled network. This is due to the limited or less research investigation that was done in this area. Most of the investigation methods tackle the problem individually such as deploying internet protocol (IP) multicast in a plain network or MPLS domain but without considering a combination of both technologies that is aware of differentiated services requirements. This thesis presents an alternative solution for the multicast differentiated services provision problem over a MPLS-TE enabled network. The approach is exposed and analyzed through a practical solution that was developed within a network simulation environment. The research presented in this thesis orchestrates the already available technologies offered by the multicast protocols suite and differentiated services (DiffServ) aware MPLS-TE that allows applying separately the constraint-based routing and admission control to different classes of services. The novelty and solution of this thesis relies on using MPLS constraint-based routing concepts (e.g.traffic trunks) in order to solve TE issues revealed during multicast traffic distribution.

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