[pt] Tradicionalmente, os equipamentos de elevação e transporte assumem uma posição de destaque na indústria, sendo as pontes rolantes os equipamentos mais utilizados. No caso da ThyssenKrupp Fundições Ltda., as pontes rolantes são responsáveis pelas principais paralisações dos negócios, trazendo prejuízos financeiros e operacionais. O emprego da IBR - Inspeção Baseada em Risco é bastante indicado para este tipo de equipamento, pois permite identificar as pontes rolantes que são críticas e deste modo estabelecer uma metodologia de inspeção eficiente, visando concentrar esforços nestes equipamentos de modo a reduzir seu risco de falha e garantir a manutenção dos negócios. Neste trabalho analisou-se um conjunto de pontes rolantes e componentes críticos da empresa ThyssenKrupp Fundições Ltda.. Para se cumprir este objetivo, foi aplicada a metodologia de IBR qualitativa para a análise do banco de dados de manutenção e inspeção. A teoria de IBR qualitativa usou uma matriz de risco COF x FOF (Conseqüência de Ocorrência de Falhas X Freqüência de Ocorrência de Falhas) onde cada uma das 20 pontes teve sua classe de risco estabelecida. Também foi feita a análise da freqüência de falhas dos componentes de todas as 20 pontes através dos registros de inspeção e manutenção localizados dentro do período de janeiro de 1995 a junho de 2002. Após a determinação das pontes rolantes críticas (risco alto e muito alto) e componentes críticos, foi elaborado um programa de inspeção para o gerenciamento dos mesmos, através de tabelas e fichas de inspeção onde a nova freqüência de inspeção foi calculada através da distribuição de probabilidade semi-empírica de Weibull. Além do programa de inspeção, foi proposta uma metodologia para análise dos resultados futuros obtidos com a aplicação do programa de inspeção e para proporcionar, através da realimentação do banco de dados, o contínuo aumento de sua eficiência. / [en] Traditionally, the transportation and elevation equipments assume a highlight position in the industry, being the overhead crane one of the mostly used equipments. As to the ThyssenKrupp Fundições Ltda, the overhead cranes are responsible for main causes for stopping of business, leading financial and operational lost. The use of RBI - Risk Based Inspection is very well indicated for this type of equipment since it allows the identification of which overhead cranes are critical and in this way the establish a mean of efficient inspection methodology, aiming to concentrate efforts on these equipments so as to reduce their failure risk and to guarantee the maintenance of the business. In this dissertation, a sub-set of overhead cranes and critical components of ThyssenKrupp Fundições Ltda was analyzed. In order to reach this objective, the RBI qualitative methodology was applied to the analysis of the maintenance and inspection database. The theory of the qualitative RBI used a risk matrix FOF x COF (Probability of Failure X Consequence of Failure) where each one of the 20 overhead crane had its class of risk established. Also, the components failure analysis frequency of all the 20 overhead cranes was made through the inspection registries situated in the period between January 1995 and June 2002. After determining the critical overhead crane (high and very high risk) and the critical components, an inspection program for their management was elaborated through means of table and inspection cards where the new inspection frequencies were determined through the Weibull distribution semi-empiric probability. Besides the inspection program, a methodology to analyze the future results obtained by the application of the inspection program was propose to offer suggestions for this continuous efficience raise.

Thesis (Master of Engineering in Mechanical Engineering)--Cape Peninsula University of Technology, 2018. / South Africa’s railway system is the most highly developed in Africa. There are different kinds of transport systems in South Africa but rail transport is considered as one of an important element of the country’s transport infrastructure. In South Africa, over 2.4 million passengers make use of rail transport to get them to their destinations. However, evidence shows that train accidents have become a common occurrence across the country. Train-related accidents such as collision, derailments, platform change incidents and commuter accidents, cost South Africa over R400 million per year. The analysis of derailments indicates that the most significant single contributor to derailments is rail breaks. This contrasts considerably with prescribed relevant local and international benchmarks, which show a much lower percentage of derailments due to rail break. The frequency of derailments due to rail breaks in South Africa seems to be higher in the northern than the southern region. Furthermore, the proportion of rail breaks that result in derailment is considerably higher than the set benchmarks and therefore, if there is a rail break, then the probability of this translating into a derailment is astonishingly high. Equally, the high incidence of derailments due to rail breaks is affected by the train length and axle load and further exacerbated by the absence of track circuitry. Since derailments are a direct function of the incidence of rail breaks, focus is required to characterize the factors causing defects on rail lines. This study investigated steel rail material by characterising the piece of the damaged rail with the aim to gain a better understanding of the wear mechanism. Chemical composition analysis of steel rail sample was conducted with the use of a Scanning Electron microscopy. Hardness of steel rail was measured with a Vickers hardness tester. An Optical Microscopy was used to examine the microstructure features of the worn rail samples. This study discovered that the worn out rail, which was produced from high carbon steel with pearlite and ferrite microstructure, undergoes decarburization and a plastic deformation process. The decarburization process happens when the rail track is heated to 700 oC and above when the carbon atoms at the surface interact with the atmospheric gases and are removed from the steel as a gaseous phase. Plastic deformation is created when the iron atoms are heated above the elastic point resulting in the permanent movement of iron atoms.

Determinadas peças cilíndricas internas exigem inspeção via súbito por dificuldades inerentes à peça ou de acesso a essas dimensões. O trabalho com esse tipo de instrumento exige operador especializado e em geral são medições demoradas e com alto nível de incerteza potencializada quando se trata de produção de médios e grandes lotes. Sabe-se que a medição acurada com baixos níveis de incerteza associada a tempos econômicos de inspeção são decisivos para o aumento da qualidade e produtividade da empresa, já que o conhecimento das dimensões é essencial para assegurar, que os componentes produzidos através dos diversos processos de manufatura estejam dentro das especificações. Este trabalho tem por objetivo apresentar o desenvolvimento de um sistema automatizado para a medição de diâmetros internos que simule a medição via comparador de diâmetros. Um robô industrial foi empregado como manipulador de transdutores de deslocamento do tipo LVDT e, substitui o operador humano. Para a realização das medidas, foi desenvolvido um programa computacional em linguagem Delphi, o que proporcionou a comunicação entre o microcomputador, LVDT e o sistema de controle do robô através de uma placa de aquisição do tipo AD/DA. Os valores medidos foram comparados com padrões metrológicos pertinentes. Os resultados foram efetivos e comprovaram a eficácia do sistema de medição proposto tanto técnica como economicamente. / Certain internal cylindrical surfaces require diameter inspection by means of bore gauges due to either shape-inherent difficulties or poor access to the measuring point. Measurements with such instruments, which call for skilled operator, are generally long and may present high uncertainty levels when inspecting mid-size or large part batches. Accurate measurements with low associated uncertainty and cost-effective inspection time are decisive to quality and productivity improvement, since dimensional information is essential to ensure that parts produced by several manufacturing processes lie within specifications. This work aims to present the development of an automated and dedicated diameter measuring system that simulates bore gauge inspection. An industrial robot, which was employed to manipulate inductive type displacement probes, replaces the human operator. In order to achieve measurements, a Delphi language object-oriented algorithm was developed to provide communication among displacement probes, a microcomputer and the robot control system, by means of an AD/DA acquisition board. Measured values were compared to pertinent metrological standards. The results were consistent and demonstrated the efficiency of the proposed measuring system, both technically and economically.

O presente trabalho teve por objetivos: 1) analisar corações bovinos obtidos no comércio varejista da cidade de São Paulo pesquisando a presença de cisticercos, a partir da técnica preconizada pelo Artigo 176 do RIISPOA Decreto-Lei 11.691\\1952, da técnica descrita por Santos (1976) e da técnica do fatiamento completo e 2) descrever a forma de apresentação destes quanto aos cortes existentes. Avaliaram-se dois grupos distintos de amostras: aquelas denominadas \"supostamente inspecionadas\", isto é, com identificação do Serviço de Inspeção Federal (SIF) e aquelas denominadas \"não inspecionadas\", ou seja, comercializadas sem identificação de origem nem selo de serviço de inspeção. Foram examinados 100 corações bovinos, sendo 29 \"não inspecionados\" (completamente fechados) e 71 \"supostamente inspecionados\" (com cortes de inspeção). As amostras foram provenientes de Mato Grosso do Sul, Goiás, São Paulo; 56% da região Oeste, 15% da região Sudeste e 29% de origem desconhecida. Não se identificou cisticercose em nenhuma das amostras, em ambos os grupos; o fatiamento dos corações bovinos é uma forma de avaliar mais minuciosamente o miocárdio em busca de alterações, porém sua utilização é viável para fins específicos de pesquisa devido à demanda de tempo gasto; já a técnica de Santos (1976) pode ser utilizada como complementar ao RIISPOA e pode ser aplicada nos Serviços de Inspeção Sanitária de Carnes; o presente estudo demonstrou que os órgãos considerados \"supostamente inspecionados\" encontravam-se todos isentos de cisticercos e de outras afecções, confirmando que a prática da inspeção veterinária de animais de açougue é eficaz na identificação e reconhecimento de alterações, é possível que o reduzido número de amostras de corações \"não inspecionados\" tenha interferido nos resultados. Sugere-se a realização de mais estudos aplicando-se as técnicas utilizadas neste trabalho avaliando maior número de corações da categoria \"não inspecionados\". / The following work has had as goals: 1) analyzing bovine hearts obtained in São Paulo city retailer commerce, researching the presence of cycticercus from the technique recommended by the article 156 of RIISPOA Decree-Law 11.691/1952 from the technique described by Santos (1976) and from the technique of complete slicing and 2) describing their way of presentation to the existing cut it has been. Evaluated two distinct groups of samples, those named \"supposedly inspectioned\" which means, with identification of the Federal Inspection Service (SIF) and those named \"not inspectioned\" which means commercialized whithout the identification of origin not the stamp of inspection service. It has been examined 100 bovines hearts, with 29 \"not inspectioned\" (completely closed) and 71 \"supposedly inspectioned\" (with inspection cuts). The samples were from Mato Grosso do Sul, Goiás, São Paulo 56% from West region, 15% from Southeast region and 29% from unknown region. Cysticercosis is not identified in any sample in both groups. The slicing of bovines hearts is a way to evaluate more precisely the myocardial in search of alterations, however, its utilization is viable for specific purposes of research due to demand for time spent. However, the technique of Santos (1976) can be utilized as complement to RIISPOA, and can be applied in sanitary inspection services of meats; The present study has demonstrated that the organs considered \"supposedly inspectioned\" have been found all exempt of cysticercus and others affections, which confirm that the practice of veterinary inspection of butcher animals is effective for identification and recognizing of alterations, it is possible that the reduced number of samples of hearts \"not inspectioned\" have interfered in the results. It suggests the realization of more studies by applying the techniques utilized in this work by evaluating a bigger number of hearts of the category \"not inspectioned\".

Motor vehicle inspection and maintenance (I/M) programs are designed to identify high-emitting vehicles and mitigate their impacts on air quality and climate. I/M programs have been traditionally ranked superior among various vehicle emission control measures by the results of cost-benefit analysis, based on the assumption that these programs will achieve the targeted emission reduction outcomes. However, the actual effects of I/M programs may be greatly uncertain and when this uncertainty is taken into account, these programs may become suboptimal. This study develops a new a cost-benefit analysis framework that links various program design consideration, such as program participation rate, identification rate and effective repair rate, to the public health benefits as well as costs of the programs. This framework helps decision makers to investigate minimum implementation requirements that at least ensure the benefits are greater than the costs of implementing the programs in order to improve the overall effectiveness of the I/M programs. To illustrate the applications of the framework, it was applied to a particulate matter oriented I/M program targeting all diesel-fueled vehicles in the city of Bangkok, Thailand, a large metropolitan area that has been suffering from severe ambient PM pollution mainly attributable to its wide use of diesel-fueled vehicles and motorcycles. It was found that the health benefits achieved from the program are sensitive to several key program design elements, including participation rate and problem vehicle identification rate, fraction of effective repairs and illegal operation rate. Other variables, such as the testing cut-points and vehicle population growth rate, only have modest effects on the overall emission reduction and consequent health benefits. Overall, the performance of multiple variables associated with I/M program design needs to be improved simultaneous in order to achieve the targeted benefits of the program.

La conteneurisation a révolutionné le commerce international au 20éme siècle. L’introduction du conteneur, comme moyen standard de transport de marchandise, a profondément impacté le commerce maritime et a radicalement changé le fonctionnement des ports. En effet, les ports n’ont cessé de se développer par la construction de nouveaux terminaux à conteneurs (TC) et également par l’amélioration de leurs services par la réduction des délais et des coûts de livraison. En parallèle, la gestion des risques dans les TC a reçu beaucoup d'attention ces dernières années en raison de l'augmentation des activités frauduleuses liées aux conteneurs. La communauté internationale a proposé plusieurs initiatives pour améliorer la sécurité du transport maritime. Cependant, l'évaluation des risques des conteneurs reste une tâche difficile, souvent due à des informations incomplètes ou ambiguës sur les conteneurs. D’autre part, la réduction de l’empreinte écologique sur l’environnement est devenue une préoccupation majeure en matière de transport conteneurisé. Face à cet enjeu écologique, les acteurs du dernier kilomètre de la chaîne logistique du conteneur doivent améliorer et optimiser leur infrastructure et penser des modes de transport terrestre de conteneurs ayant une empreinte environnementale moindre que les modes de transports classiques à gasoil, sans toutefois impacter les performances. Dans cette optique, le premier objectif de cette thèse se focalise autour l’amélioration de la performance du processus d’inspection des conteneurs. Ainsi, nous proposons une nouvelle approche adaptative de la priorisation d’inspection des conteneurs. Nous avons nommé cette approche APRICOIN (Adaptive PRIoritizing Container INspection). Cette approche exploite le concept du produit intelligent ainsi que de la logique floue et les techniques de fouille de données. Cette approche est basée sur trois étapes. La première étape vise l’amélioration du flux informationnel et en assurant sa véracité et ce moyennant les capacités du conteneur intelligent. Ainsi on propose un descriptif enrichi du conteneur (DEC). La deuxième étape consiste à prioriser l’inspection des conteneurs en lui attribuant un score de risque à l’aide de la logique floue. La dernière étape consiste à prioriser l’inspection des conteneurs et exploiter les résultats d’inspection afin d’ajuster la précision de l’algorithme APROCOIN et s’adapter aux nouveaux facteurs de risque moyennant les techniques de fouille de données. Afin de valider l’approche proposée, une étude de cas illustratif a été réalisée ainsi qu’une étude comparative avec d’autres approches alternatives. Le deuxième objectif de cette thèse se focalise sur le projet green Truck qui vise particulièrement les transporteurs routiers de conteneurs à courtes distances dans la zone portuaire en assurant une transition énergétique de la flotte de tracteurs gasoil vers des tracteurs électriques à batteries rechargeables. Le projet s’intéresse à une technique récente de rechargement des batteries, à savoir le « Biberonnage ». Cette technologie est inspirée du fonctionnement de certains bus électriques. Elle consiste à exploiter les courts temps d’attentes du véhicule, comme par exemple la monté et la descente des passagers pour le cas des bus, afin de recharger automatiquement la batterie du véhicule. Ainsi dans cette thèse, nous avons exploré différentes techniques et modes de rechargement rapide des batteries de tracteurs routiers électriques compte tenu des contraintes d’exploitation, et d’évalué la faisabilité économique de la mise en œuvre d’un système comprenant le véhicule et l’infrastructure électrique. L’outil de simulation Anylogic a permis de dimensionner les batteries et les bornes de recharge des véhicules électriques, en plus de fournir aux décideurs des résultats technico-économiques avec des représentations animées et graphiques en 3D. / Containerization revolutionized international trade in the 20th century. The introduction of the container, as a standard means of transporting goods, has had a profound impact on maritime trade and has radically changed the functioning of ports. Indeed, ports have continued to grow through the construction of new container terminals (CT) and also by improving their services by reducing delays and delivery costs. At the same time, risk management in CTs has received a lot of attention in recent years due to an increase in fraudulent container activities. The international community has proposed several initiatives to improve the security of maritime transport. However, the risk assessment of containers remains a difficult task, often due to incomplete or ambiguous container information. On the other hand, reducing the ecological footprint on the environment has become a major concern in containerized transport. Faced with this ecological challenge, the last-mile players in the container logistics chain must improve and optimize their infrastructure and think of new land transport modes of containers with a lower environmental footprint than conventional diesel transport modes, without having an impact on performance. With this in mind, the first objective of this thesis focuses on improving the performance of the container inspection process. Thus, we propose a new adaptive approach to container inspection prioritization. We named this approach APRICOIN (Adaptive PRIoritizing Container INspection). This approach exploits the concept of intelligent product as well as fuzzy logic and data mining techniques. This approach is based on three stages. The first step is to improve the information flow and to ensure this truthfulness by means of the capabilities of the intelligent container. Thus we propose an enriched description of the container (DEC). The second step is to prioritize container inspection by assigning a risk score using fuzzy logic. The final step is to prioritize the inspection of the containers and use the inspection results to adjust the accuracy of the APROCOIN algorithm and to adapt to the new risk factors using the data mining technique. In order to validate the proposed approach, an illustrative case study was conducted as well as a comparative study with other alternative approaches. The second objective of this thesis focuses on the green truck project, which is particularly aimed at short-haul container road hauliers in the port area by ensuring an energy transition from the fleet of diesel tractors to electric tractors with rechargeable batteries. It consists in exploiting the short wait times of the vehicle, in order to automatically recharge the vehicle's battery. Thus, in this thesis, we have explored the different techniques and methods of recharging batteries of electric road tractors taking into account operating constraints, and evaluate the economic feasibility of implementing such system. The Anylogic simulation was used to size the batteries and the charging stations of electric vehicles. In addition technical and economic results with 3D animated and graphic representations was provided.

<div>Path planning is the generation of paths for the robots to navigate based on some constraints. Coverage path planning is where the robots needs to cover an entire work space for various applications like sensing, inspection and so on. Though there are numerous works on 2D coverage and also coverage using a single robot, the works on 3D coverage and multi-agents are very limited. This thesis makes several contributions to multi-agent path planning for 3D structures.</div><div><br></div><div>Motivated by the inspection of 3D structures, especially airplanes, we present a 3D coverage path planning algorithm for a multi-UAV system. We propose a unified method, where the viewpoints selection and path generation are done simultaneously for multiple UAVs. The approach is scalable in terms of number of UAVs and is also robust to models with variations in geometry. The proposed method also distributes the task uniformly amongst the multiple UAVs involved and hence making the best use of the robotics team. The uniform task distribution is an integral part of the path planner. Various performance measures of the paths generated in terms of coverage, path length and time also has been presented. </div>

En la tramitación de los procedimientos administrativos sancionadores, los funcionarios afrontan dificultades para notificar los actos administrativos, las cuales no solo se limitan a la determinación del domicilio correcto del administrado en el cual se harán llegar los actos, sino además en el hecho de que, una vez determinado dicho domicilio, se presentan supuestos de diligencias de notificación infructuosas, ya sea porque la dirección resulta inexistente o porque el administrado ya no reside en dicho lugar, ello debido a que el domicilio declarado por el administrado ante el Registro Nacional de Identificación y Estado Civil es incorrecto o no se encuentra actualizado, siendo que dicha situación, sumado a una legislación que pretende ser muy garantista, ha llevado a que las entidades de la Administración Pública destinen recursos significativos en la notificación de actos a través de la publicación de edictos. Usando el método de investigación descriptiva con enfoque cualitativo, en la presente investigación se demostrará que la aplicación del régimen de notificación establecido en la Ley del Procedimiento Administrativo General, Ley N° 27444, viene siendo ineficiente, generando costos innecesarios a la Administración. Ante dicha situación, se concluye que se deben ejecutar una serie de acciones, que no solo implican la modificación de la citada Ley, y de la Ley Orgánica del Registro Nacional de Identificación y Estado Civil, Ley N° 26497, sino que además implican dotar al procedimiento de expedición del Documento Nacional de Identidad y al procedimiento del cambio del dato domiciliario, del uso del Sistema Georeferenciado para mejorar la confiabilidad de los datos declarados por los ciudadanos, desarrollar una campaña de concientización respecto de la importancia de actualizar el domicilio en el Documento Nacional de Identidad, y optimizar las acciones de fiscalización del RENIEC respecto del cumplimiento de la obligación de actualizar el domicilio. / In the processing of administrative sanctions procedures, officials face difficulties in notifying administrative acts, which are not only limited to the determination of the correct domicile of the petitioner to which the documents will be sent, but also in the fact that, once this domicile is determined, there are cases of unsuccessful notification diligences. This may happen because the address is non-existent, the petitioner no longer resides in that location, or because the domicile declared by the petitioner before the National Registry of Identification and Marital Status is incorrect or is not updated. This situation, added to a legislation that seeks to provide all possible guarantees, has led to the Public Administration entities allocate significant resources in the notification of acts through the publication of legal notices. The descriptive research method involving a qualitative approach has been applied to conduct this research study, which will demonstrate that the application of the notification regime established in the General Administrative Procedure Act, Law No. 27444, is inefficient, and creates unnecessary administrative costs. It, therefore, follows that a series of actions must be executed, which do not only imply the modification of the Law mentioned above, and the Organic Law of the National Registry of Identification and Marital Status, Law No. 26497, but also the implementation of the Georeferenced System to improve the reliability of the data declared by citizens in their Identity Cards. This action will be critical to carry out an awareness campaign regarding the importance of updating the domicile in the Peruvian Identity Card to optimize RENIEC's inspection actions regarding fulfillment with the obligation to update the domicile. / Trabajo de investigación

Image processing systems used in Vision Assisted Dimensional Inspection usually output a set of boundary pixels representing the part edges. This boundary information must be divided into several subsets representing the various edges of the actual object, so that comparisons with the nominal part can be made. The purpose of this project is to devise a method to divide the set of pixels obtained from the image processing system into subsets of pixels. Each of these subsets represent an edge in the contour of the actual object. This method must also detect transition points between the adjacent features. This project addresses only planar contours which are composed of straight and circular edges. Two new algorithms have been developed, the first algorithm detects the transition points involving straight edges and the second algorithm finds the transition points when circular features are involved. In addition, the measured features are also matched with their nominal counterparts. The performance of these algorithms are demonstrated by simulated as well as images from the vision system.

This thesis documents a PhD research program undertaken at Swinburne University of Technology between the years 2000 and 2004. The research was funded by the Cooperative Research Centre for Cast Metals Manufacturing and was undertaken in collaboration with Nissan Casting Plant Australia Pty Ltd and the Ford Motor Company Australia Limited. This thesis reports on the investigation of the possibility of using an ultrasonic sensing-based, non-destructive testing system to detect gas porosity defects in aluminium die casting parts with rough surfaces. The initial intention was to develop a procedure to obtain ultrasonic signals with the maximum possible amplitude from defects within the rough surface areas of the castings. A further intention was to identify defects with the application of a suitable signal processing technique to the raw ultrasonic signal. The literature review has indicated that ultrasonic techniques have the potential to be used to detect subsurface defects in castings. The possibility of classifying very weak ultrasonic signals obtained from rough surface sections of castings through a neural network approach was also mentioned in the literature. An extensive search of the literature has indicated that ultrasonic sensing techniques have not been successfully used to detect sub-surface defects in aluminium die castings with rough surfaces. Ultrasonic inspection of castings is difficult due to the influence of microstructural variations, surface roughness and the complex shape of castings. The design of the experimental set-up used is also critical in developing a proper inspection procedure. The experimental set-up of an A-scan ultrasonic inspection rig used in the research is described in this thesis. Calibration of the apparatus used in the inspection rig was carried out to ensure the reliability and repeatability of the results. This thesis describes the procedure used to determine a suitable frequency range for the inspection of CA313 aluminium alloy castings and detecting porosity defects while accommodating material variations within the part. The results obtained from ultrasonic immersion testing indicated that focused probes operating at frequencies between 5 MHz and 10 MHz are best suited for the inspection of castings with surface roughness Ra values varying between 50 [micro milli] and 100 [micro milli]. For the purpose of validating the proposed inspection methodology, gas porosity defects were simulated through side-drilled holes in the in-gate section of selected sample castings. Castings with actual porosity defects were also used in this research. One of the conclusions of this research was that it was extremely difficult to detect defects in castings with surface roughness above 125 [micro milli]. Once the ultrasonic signal data was obtained from the sample aluminium die castings with different surface roughness values ranging from 5 [micro milli] to 150 [micro milli] signal analysis was carried out. Signal feature extraction was achieved using Fast Fourier Transforms (FFT), Principal Component Analysis (PCA) and Wavelet Transforms (WT) prior to passing the ultrasonic signals into a neural network for defect classification. MATLAB tools were used for neural network and signal pre-processing analysis. The results indicated that poor classification (less than 75%) was achieved with the WT, PCA and combination of FFT/PCA and WT/PCA pre-processing techniques for rough surface signals. However, the classification of the signals pre-processed with the combination of WT/FFT, FFT/WT and FFT/WT/PCA classifiers provided much better classification of more than 90% for smooth surface signals and 78% to 84% for rough surface signals. The results obtained from ultrasonic testing of castings with both real and simulated defects were validated with X-ray analysis of the sample castings. The results obtained from this research encourage deeper investigation of the detection and characterisation of sub-surface defects in castings at the as-cast stage. Implications for the industrial application of these findings are discussed and directions for further research presented in this thesis.