Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

This thesis presents the development and validation of a novel interface modelling methodology integrated with a system architectural analysis framework that emphasises the need to manage the integrity of deriving and allocating requirements across multiple levels of abstraction in a structured manner. The state of the art review in this research shows that there is no shared or complete interface definition model that could integrate diverse interaction viewpoints for defining system requirements with complete information. Furthermore, while existing system modelling approaches define system architecture with functions and their allocation to subsystems to meet system requirements, they do not robustly address the importance of considering well-defined interfaces in an integrated manner at each level of systems hierarchy. This results in decomposition and integration issues across the multiple levels of systems hierarchy. Therefore, this thesis develops and validates following: -Interface Analysis Template as a systematic tool that integrates diverse interaction viewpoints for modelling system interfaces with intensive information for deriving requirements. -Coupling Matrix as an architecture analysis framework that not only allocates functions to subsystems to meet requirements but also promotes consistent consideration of well-defined interfaces at each level of design hierarchy. Insights from the validation of developed approach with engineering case studies within an automotive OEM are discussed, reflecting on the effectiveness, efficiency and usability of the methods.

This thesis proposes a hypothesis that a conventional, and essentially manual, HAZOP process can be improved with information obtained with model-based dynamic simulation, using a Monte Carlo approach, to update a Bayesian Belief model representing the expected relations between cause and effects - and thereby produce an enhanced HAZOP. The work considers how the expertise of a hazard and operability study team might be augmented with access to behavioural models, simulations and belief inference models. This incorporates models of dynamically complex system behaviour, considering where these might contribute to the expertise of a hazard and operability study team, and how these might bolster trust in the portrayal of system behaviour. With a questionnaire containing behavioural outputs from a representative systems model, responses were collected from a group with relevant domain expertise. From this it is argued that the quality of analysis is dependent upon the experience and expertise of the participants but this might be artificially augmented using probabilistic data derived from a system dynamics model. Consequently, Monte Carlo simulations of an improved exemplar system dynamics model are used to condition a behavioural inference model and also to generate measures of emergence associated with the deviation parameter used in the study. A Bayesian approach towards probability is adopted where particular events and combinations of circumstances are effectively unique or hypothetical, and perhaps irreproducible in practice. Therefore, it is shown that a Bayesian model, representing beliefs expressed in a hazard and operability study, conditioned by the likely occurrence of flaw events causing specific deviant behaviour from evidence observed in the system dynamical behaviour, may combine intuitive estimates based upon experience and expertise, with quantitative statistical information representing plausible evidence of safety constraint violation. A further behavioural measure identifies potential emergent behaviour by way of a Lyapunov Exponent. Together these improvements enhance the awareness of potential hazard cases.

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Over the past decade the capabilities of autonomous systems have been steadily increasing. Unmanned systems are moving from systems that are predominantly remotely operated, to systems that include a basic decision making capability. This is a trend that is expected to continue with autonomous systems making decisions in increasingly complex environments, based on more abstract, higher-level missions and goals. These changes have significant implications for how these systems should be designed and engineered. Indeed, as the goals and tasks these systems are to achieve become more abstract, and the environments they operate in become more complex, are current approaches to verification and validation sufficient? Domain Specific Modelling is a key technology for the verification of autonomous systems. Verifying these systems will ultimately involve understanding a significant number of domains. This includes goals/tasks, environments, systems functions and their associated performance. Relational Model Transformations provide a means to utilise, combine and check models for consistency across these domains. In this thesis an approach that utilises relational model transformation technologies for systems verification, Systems MDD, is presented along with the results of a series of trials conducted with an existing relational model transformation language (QVT-Relations). These trials identified a number of problems with existing model transformation languages, including poorly or loosely defined semantics, differing interpretations of specifications across different tools and the lack of a guarantee that a model transformation would generate a model that was compliant with its associated meta-model. To address these problems, two related solvers were developed to assist with realising the Systems MDD approach. The first solver, MMCS, is concerned with partial model completion, where a partial model is defined as a model that does not fully conform with its associated meta-model. It identifies appropriate modifications to be made to a partial model in order to bring it into full compliance. The second solver, TMPT, is a relational model transformation engine that prioritises target models. It considers multiple interpretations of a relational transformation specification, chooses an interpretation that results in a compliant target model (if one exists) and, optionally, maximises some other attribute associated with the model. A series of experiments were conducted that applied this to common transformation problems in the published literature.

This is the thirteenth workshop to be organised under the postgraduate programmes in electrical and electronic engineering (EEE). In total, twenty-nine papers, divided into eight themes, comprise the Proceedings.

Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: This thesis documents the research conducted into the control of the feeder subsystem of a Reconfigurable Assembly System (RAS). The research was motivated by a new set of modern manufacturing requirements associated with an aggressive and dynamic global market. The motivation can be more specifically attributed to the need for selective automation, through the installation of reconfigurable systems, in the South African manufacturing industry. The objective of the research was to implement and evaluate Multi-Agent Systems (MASs) and IEC 61499 function block systems as potential control strategies for reconfigurable systems. The control strategies were implemented for the control of the feeder subsystem of an experimental RAS at Stellenbosch University. The subsystem's hardware consisted of a singulation unit with a machine vision camera, part magazines and a six DOF pick-'n-place robot. The structure of the control strategies is based on the ADACOR holonic reference architecture. The mapping of the subsystem holons to the structures of the control strategies is explained. The development and implementation of the control strategies, along with the accompanying lower level software, is described in detail. A system reconfigurability assessment was performed and the results are discussed. The assessment was performed at two levels – the Higher Level Control (HLC) (where the control strategies were implemented) and the low level control and hardware. The assessment was done through four reconfiguration experiments. The evaluation of the HLC was done through both quantitative and qualitative performance measures. The implications of the reconfiguration, involved in each of the respective experiments, on the low level software and hardware are discussed. The experimental results show that agent-based control adds more reconfigurability to the feeder subsystem than IEC 61499 function block control, and that agents have more advantages regarding customizability, convertibility and scalability than IEC 61499 function blocks. Also, the ability of agent-based control to implement reconfiguration changes during subsystem operation makes it more suitable to the case study application. / AFRIKAANSE OPSOMMING: Hierdie tesis dokumenteer die navorsing gedoen in die beheer van die voerder sub-stelsel vir 'n herkonfigureerbare monteringstelsel. Die navorsing was gemotiveer deur „n nuwe stel vereistes vir moderne vervaardiging wat met 'n aggresiewe en dinamiese globale mark geassosieer word. Die motivering kan meer spesifiek toegeskryf word aan die behoefte tot selektiewe outomatisasie, deur middel van die implimentering van herkonfigureerbare stelsels, in the Suid-Afrikaanse vervaardigingsnywerheid. Die doel van die navorsing is om multi-agent stelsels en IEC 61499 funksie-blok stelsels, as potensiële beheerstrategiëe vir herkonfigureerbare stelsels, te implementer en evalueer. Die beheerstrategiëe was geïmplementeer vir die voerder sub-stelsel van „n eksperimentele herkonfigureerbare monteringstelsel by Universiteit Stellenbosch. Die hardeware behels „n skeier-eenheid (singulation unit) met „n masjienvisie kamera, onderdeelmagasyne en „n ses-vryheidsgraad gearktikuleerde optel-en-plaas robot. Die struktuur van die beheerstrategiëe is gebaseer op die ADACOR holoniese verwysingsargitektuur. Die afbeelding van die sub-stelsel holons na die struktuur van die beheerstrategiëe word verduidelik. Die ontwikkeling en implementering van die beheerstrategiëe, asook die gepaardgaande laer-vlak programmatuur, word in detail beskryf. Die stelsel se herkonfigureerbaarheid was geassesseer en die resultate daarvan word bespreek. Die assessering was op twee vlakke gedoen – die hoër-vlak beheer (waar die beheerstrategiëe geimplementeer was) en die lae-vlak beheer en hardeware. Die assessering was gedoen deur middel van vier herkonfigurasie eksperimente. Die hoër-vlak beheer was geëvalueer deur beide kwalitatiewe en kwantitatiewe metings. Die implikasies van die herkonfigurasie, betrokke by die onderskeie eksperimente, op die lae-vlak beheer en hardeware word beskryf. Die eksperimentele resultate wys dat agent-baseerde beheer meer herkonfigureerbaarheid tot die voerder sub-stelsel toevoeg as IEC 61499 funksie-blok beheer. Dit is geïdentifiseer dat agente meer voordele inhou ten opsigte van aanpasbaarheid, skakelbaarheid en skaalbaarheid as IEC funksie-blokke. Agent-baseerde beheer laat ook toe dat herkonfigurasieveranderinge tydens sub-stelsel werking geïmplimenteer kan word – dus is dit meer geskik vir aanwending in die gevallestudie.

O presente trabalho busca compreender a importância que o Banco Nacional de Desenvolvimento Econômico e Social (BNDES) ganha a partir de 2003 com as ampliações dos financiamentos voltados para a construção de sistemas de engenharia, não somente dentro do território nacional, mas também no exterior (sobretudo na América do Sul). Partindo do processo de integração física das nações sulamericanas e da instalação de solidariedades geográficas (Santos, 1996) entre as regiões do continente, procuramos analisar as complementaridades nos territórios envolvidos em financiamentos dos bancos de desenvolvimento, em especial o BNDES, no qual se articulam Estados e empresas privadas na produção de novos sistemas de engenharia no continente. Nesse sentindo, buscamos compreender as verticalidades e horizontalidades geradas no espaço continental, dando ênfase no caso da fronteira do Brasil com a Guiana Francesa, onde foram instalados nos fixos geográficos que afetam diretamente a integração destes dois países (principalmente a Ponte Binacional Brasil-Guiana e a BR-156). / This paper seeks to understand the importance that the National Bank for Economic and Social Development (BNDES) wins from 2003 with the expansion of financing aimed at the construction of engineering systems, not only within the country but also abroad (especially in South America). Starting from the physical integration of South American nations and the installation of geographical solidarities (Santos, 1996) between the regions of the continent process, we analyzed the complementarities in the territories involved in financing from development banks, especially BNDES, which are articulated States and private companies in the production of new engineering systems on the continent. In that sense, we seek to understand the uprights and horizontalities generated in continental space, emphasizing the case of Brazil\'s border with French Guiana, where they were installed in the geographic fixed that directly affect the integration of these two countries (mainly Brazil-Guyana Binational Bridge and BR-156).

Thesis (M.S.) -- Mississippi State University. Department of Aerospace Engineering. / Title from title screen. Includes bibliographical references.