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There is a trend in manufacturing towards fully automated production facilities in which all operations are integrated by computer based information systems. The current generation of industrial inspection systems lack the necessary flexibility to operate in these environments. AI based Image Understanding systems have the necessary level of generality, achieved through the use of domain specific object models. These models are used to guide early visual processing, and must be supplied to the system. Current theories in cognitive psychology call for a reevaluation of the role of such 'auxiliary' knowledge in early visual processing. Recent work suggests that very general cognitive processes may build up a hierarchical representation of the world. The emphasis is currently on such generic cognitive processes rather than on the use of world knowledge. A novel approach to image processing, in which emphasis is placed on generic low and intermediate level techniques, is proposed in this thesis. This approach, termed the descriptor approach, delays the use of domain specific models until a full description of the image has been produced. A prototype industrial inspection system has been implemented, based on the descriptor approach: the Hierarchical Scene Description (HISD) system. General image features are extracted from images of populated PCBs, and subsequently transformed into a database of prolog facts by an interface subsystem. Finally the intermediate level vision subsystem uses rules to reason about these features, building up a semantic net based description of the scene. HISD successfully builds up hierarchical descriptions of real industrial PCB images in terms of geometric shapes, their coordinates, and spatial relationships between shapes. The results are displayed graphically and are achieved without the use of any object models, thus avoiding the problems of inflexibility and lack of generality associated with more complex model based systems.

This thesis describes an integrated approach to fatigue cracking, reliability and inspection of offshore structures. The basis of the approach is statistical in nature and draws on recent experimental data and field measurements. It is intended as a working tool for those engaged in design, structural appraisal and sub-sea inspection of steel jacket structures. A review of current practice has been made and the requirements of an integrated approach are established. An approach is proposed comprising a series of compatible models dealing with fatigue cracking, the reliability of cracked joints and the inspection of welds for fatigue cracks. The primary linking parameter is the distribution of fatigue crack size which is considered as a time dependent variable. An integral part of the approach is a new statistically-based fatigue crack growth model. This is developed and the parameters involved in the model estimated from an analysis of experiment and oceanographic data. For any fatigue calculation the model allows the corresponding fatigue crack growth distribution to be estimated for any time during, or beyond, the nominal fatigue life. A number of example calculations are included; and using one of these a Bayesian procedure for revising fatigue lives in the light of inspection results is demonstrated. The effect of fatigue cracking upon the various modes of tubular joint failure is considered using linear statistical models. Example calculations are performed for a typical joint. An inspection strategy is proposed based on the concept of minimising life costs, including risk costs arising from the consequences of possible structural failure. This allows alternative inspection plans to be evaluated and compared, and a typical example calculation is included. The approach is discussed in the context of possible alternative approaches and areas for further related research are identified.

The use of key performance indicators has dramatically increased over the last twenty or so years. Their introduction has been largely justified on the grounds that high stakes proxy indicators (test and exam results), increase accountability which will in turn `drive up' overall performance. Whilst there has been some evidence that measured standards have risen, there have been associated costs, as well as claims of unintended or dysfunctional consequences. The place of KPIs within the broader organisational and managerial context was firstly considered. with particular reference to generic management and accounting theory. Secondly, the results of a questionnaire survey of 162 heads and teachers in England and Scotland was reported. The key findings included evidence that KPIs had a narrowing effect on the curriculum, that they tended to undermine heads and teachers, and encouraged a blame culture. There was also evidence that they caused schools to concentrate on targets at the expense of other important objectives, as well as concentrating on `boarder-line' pupils. English primary schools reported far more dysfunctional behaviour due to KPIs, than did their Scottish counter parts. This was attributed to league tables which Scottish primaries do not have. At the secondary level the results were similar, tables are published for secondary schools in both countries. There was widespread support for changes to the KPIs, including the use of a wider range of measures and `value added' indicators, as well as discontinuing league tables. Improvements to the KPI systems were discussed, including the use of `balanced score card' systems; however, it was argued that such technical changes need to be accompanied by more fundamental organisational changes. There needs to be `top down' leadership, which devolves trust and responsibility, rather than blame and accountability; and one that will develop and nurture a true learning culture throughout the education system.

University of Macau / Faculty of Science and Technology. / Department of Electromechanical Engineering

Este trabalho apresenta os resultados da aplicação da metodologia de inspeção não intrusiva (INI) em equipamentos do sistema de dessulfurização de gás numa plataforma petrolífera, com o auxílio da inspeção baseada em risco utilizando a norma API RP 581. A inspeção não intrusiva é aplicada tendo como fundamentos as guias de inspeção, como a DNV-RP-G103, que reúne informações de como executar e justificar o seu uso, a fim de garantir a segurança das instalações, eliminando a necessidade de uma parada do equipamento para a realização da inspeção. Contudo nem todos os equipamentos puderam ser inspecionados por esta metodologia, devido a limitações operacionais e/ou construtivas. O trabalho conclui que a inspeção não intrusiva pode ser aplicada à inspeção de equipamentos sem prejuízo ao mapa de risco do equipamento ou da unidade, e naqueles onde não é possível à utilização somente da metodologia, a mesma poderá ser aplicada em conjunto com a inspeção convencional fornecendo informações importantes sobre o estado do equipamento, melhorando assim a confiabilidade do planejamento da parada de manutenção e uma redução dos custos envolvidos. / This paper presents the results of applying the methodology of non-intrusive inspection (INI) in electrical system flue gas desulphurization an oil rig, with the help of riskbased inspection using the API RP 581. The non-intrusive inspection is implemented with the guides as the foundations of inspection, such as DNV-RP-G103, which gathers information on how to make and justify its use, to ensure the safety of installations, eliminating the need for a parade equipment to perform the inspection. However not all equipment could be inspected by this method, due to operational limitations and / or constructive. The paper concludes that the non-intrusive inspection can be applied to inspection of equipment subject to the risk map of the equipment or unit, and those where it is not possible to use only the methodology, it may be applied along with conventional inspection providing important information on the status of the equipment, thereby improving the reliability of planning maintenance shutdown and lower costs.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Thesis (B.Sc)--University of Hong Kong, 2004. / Includes bibliographical references.

To get better EDFA performance, we have to improve the coupling efficiency of semiconductor laser diode(LD) and fiber optic; also, increase the LD¡¦s power to achieve. There are plenty of ways to have higher coupling efficiency out there. Some of them even can reach 90% or better coupling efficiency. However, because of light field property, high-power LD output will not be able to apply to high coupling efficiency structure. Therefore, using cascaded fiber can improve coupling efficiency and maintain its characteristic in high-power laser output environment. Cascaded fiber is connecting SMF and GIF together. Although cascaded fiber can increase high-power LD output of coupling efficiency, it has 5% to 10% of loss during manufacture because of the inspect error of melting surface. We use CCD to observe the cascaded fiber¡¦s melting surface. Then, we pair with special light source to do the examination. Thus, we can overcome the obstacle, do automatically manufacture of the cascaded fiber in a small area, and reduce the coupling loss of cascaded fiber.