Over the past ten years, there has been increased use of electronic power processing in alternative, sustainable, and distributed energy sources, as well as energy storage systems, transportation systems, and the power grid. Three-phase voltage source converters (VSCs) have become the converter of choice in many ac medium- and high-power applications due to their many advantages, such as high efficiency and fast response. For transportation applications, high power density is the key design target, since increasing power density can reduce fuel consumption and increase the total system efficiency. While power electronics devices have greatly improved the efficiency, overall performance and power density of power converters, using power electronic devices also introduces EMI issues to the system, which means filters are inevitable in those systems, and they make up a significant portion of the total system size and cost. Thus, designing for high power density for both power converters and passive components, especially filters, becomes the key issue for three-phase converters. This dissertation explores two different approaches to reducing the EMI filter size. One approach focuses on the EMI filters itself, including using advanced EMI filter structures to improve filter performance and modifying the EMI filter design method to avoid overdesign. The second approach focuses on reducing the EMI noise generated from the converter using a three-level and/or interleaving topology and changing the modulation and control methods to reduce the noise source and reduce the weight and size of the filters. This dissertation is divided into five chapters. Chapter 1 describes the motivations and objectives of this research. After an examination of the surveyed results from the literature, the challenges in this research area are addressed. Chapter 2 studies system-level EMI modeling and EMI filter design methods for voltage source converters. Filter-design-oriented EMI modeling methods are proposed to predict the EMI noise analytically. Based on these models, filter design procedures are improved to avoid overdesign using in-circuit attenuation (ICA) of the filters. The noise propagation path impedance is taken into consideration as part of a detailed discussion of the interaction between EMI filters, and the key design constraints of inductor implementation are presented. Based on the modeling, design and implementation methods, the impact of the switching frequency on EMI filter weight design is also examined. A two-level dc-fed motor drive system is used as an example, but the modeling and design methods can also be applied to other power converter systems. Chapter 3 presents the impact of the interleaving technique on reducing the system passive weight. Taking into consideration the system propagation path impedance, small-angle interleaving is studied, and an analytical calculation method is proposed to minimize the inductor value for interleaved systems. The design and integration of interphase inductors are also analyzed, and the analysis and design methods are verified on a 2 kW interleaved two-level (2L) motor drive system. Chapter 4 studies noise reduction techniques in multi-level converters. Nearest three space vector (NTSV) modulation, common-mode reduction (CMR) modulation, and common-mode elimination (CME) modulation are studied and compared in terms of EMI performance, neutral point voltage balancing, and semiconductor losses. In order to reduce the impact of dead time on CME modulation, the two solutions of improving CME modulation and compensating dead time are proposed. To verify the validity of the proposed methods for high-power applications, a 100 kW dc-fed motor drive system with EMI filters for both the AC and DC sides is designed, implemented and tested. This topology gains benefits from both interleaving and multilevel topologies, which can reduce the noise and filter size significantly. The trade-offs of system passive component design are discussed, and a detailed implementation method and real system full-power test results are presented to verify the validity of this study in higher-power converter systems. Finally, Chapter 5 summarizes the contributions of this dissertation and discusses some potential improvements for future work. / Ph. D.

ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper discusses using the CAN (Control Area Network) Bus protocol for control and status of flight test data acquisition systems. The application of the CAN (Control Area Network) on an F/A-18 aircraft will be discussed in detail.

Electrical methods of geophysical survey are known to produce results that are hard to predict at different times of the year, and under differing weather conditions. This is a problem which can lead to misinterpretation of archaeological features under investigation. The dynamic relationship between a ‘natural’ soil matrix and an archaeological feature is a complex one, which greatly affects the success of the feature’s detection when using active electrical methods of geophysical survey. This study has monitored the gradual variation of measured resistivity over a selection of study areas. By targeting difficult to find, and often ‘missing’ electrical anomalies of known archaeological features, this study has increased the understanding of both the detection and interpretation capabilities of such geophysical surveys. A 16 month time-lapse study over 4 archaeological features has taken place to investigate the aforementioned detection problem across different soils and environments. In addition to the commonly used Twin-Probe earth resistance survey, electrical resistivity imaging (ERI) and quadrature electro-magnetic induction (EMI) were also utilised to explore the problem. Statistical analyses have provided a novel interpretation, which has yielded new insights into how the detection of archaeological features is influenced by the relationship between the target feature and the surrounding ‘natural’ soils. The study has highlighted both the complexity and previous misconceptions around the predictability of the electrical methods. The analysis has confirmed that each site provides an individual and nuanced situation, the variation clearly relating to the composition of the soils (particularly pore size) and the local weather history. The wide range of reasons behind survey success at each specific study site has been revealed. The outcomes have shown that a simplistic model of seasonality is not universally applicable to the electrical detection of archaeological features. This has led to the development of a method for quantifying survey success, enabling a deeper understanding of the unique way in which each site is affected by the interaction of local environmental and geological conditions.

This interpretive study explores the effect of employee share ownership (ESO) plans (SIP, EMI and SAYE) on employee attitudes and behaviours at work by taking into account the role of Psychological Ownership (PO), characterised by feelings of "mine" and "ours". The key concepts and relationships specified in positivist causal models of ESO and PO were translated into a set of interview questions and were used to explore with 37 ESO plan participants and 9 ESO plan managers whether the causal models fit with the way they explain for themselves their experiences of and reactions to employee share ownership. In doing this, the study has responded to suggestions made in the research literature to compare the attitudinal effects of different types of employee ownership, avoid the manipulation of large, readily available data sets, and to provide insights into the causal processes surrounding ESO. Overall, three main themes can be identified from employees responses, which appeared to have some influence on whether or not the share plan was felt to have an impact. First, employees interest in making money, and expectations of whether they would, played a large part in their explanations of ESO s impact. A number of employees felt the share plan helped retain them in the organisation. However, this did not appear to be because the plan was making then more committed, in the sense that they would feel more emotionally attached, or a greater sense of identification with the company. Instead, the plan was retaining employees by causing them to make an assessment of the costs associated with leaving (continuance commitment). Second, many of the ESO outcomes featured in the academic literature were already felt to be experienced by employees at work and ESO was felt to only be able to add in a small way to what was already being experienced. Finally, in some situations ESO represented something quite meaningful to employees. ESO was sometimes interpreted as being a sign that the company valued employees, wanted them to feel part of the company, or that the employees were important to the company. The offer to participate in ESO was interpreted in some cases as being an acknowledgement of hard work, and an indication of how the company wanted employees to feel. This was found to enhance ESO s capacity to impact how employees felt at work. However, with regards to most outcomes explored in this study, employees reported little or no impact from ESO. Findings suggested that the ESO plans, even when they were felt to lead to feelings of PO, provided little incentive to work harder. PO was also found to play little or no part in employees explanations of how share plans had an impact or why they did not. Employees felt they had a long wait before making a financial return and no tangible day to day benefits of ESO. This led the plans, and the potential gains that could be made, to be perceived as very long term, and easily forgotten. Finally, this study highlights a mismatch between the causal models of ESO and PO, the conventional wisdom of ESO, the views of the ESO managers, and the interpretations of the employees who were interviewed and raises the question of whether ESO achieves what it is intended (and often believed) to achieve.

Until approximately 50 years ago, wireless electronics was confined to military purposes. With the advancement of technology, consumer electronics found widespread applications in almost every aspect of our lives and numerous devices were developed using electromagnetic waves to transfer different types of data. In light of such advancements, the electromagnetic compatibility (EMC) evolved from a military concept to regulate the radio frequency requirements of the battlefield equipment to a mature and essential part in manufacturing and employing electronic devices. Medical devices were no exception and largely benefited from the ease of connectivity and mobility provided by usage of wireless electronics. Due to the sensitive nature of medical devices and extreme consequences of their malfunction, EMC grew to a centric issue in design and production of such devices. This work examines the electromagnetic compatibility of a wearable biomedical measurement system used for the assessment of mental stress of combatants in real time. This system was developed as a part of the ARTEC project and supported by the Spanish Ministry of Defense through the Future Combatant program [1]. We focus on the EMC of the electrocardiogram of the system and aim to identify its EMC requirements of this system while assessing it against various standards and protocols. Throughout this study, we elucidate the fundamentals of electromagnetic compatibility with specific attention to medical devices. Furthermore, we present our results after conducting several EMC tests to measure the compatibility of the electrocardiogram device using the Intertek guidelines. The emission test was performed while essential counter measures such as appropriate shielding and anti-interference filters had been applied.

Orientador: Jozué Vieira Filho / Resumo: As técnicas de detecção de danos baseadas na Impedância Eletromecânica (EMI) baseiam-se na capacidade dos materiais piezoeléctricos em atuar como sensores e atuadores e contribuem para o desenvolvimento de sistemas de Structural Health Monitoring (SHM). As técnicas clássicas baseadas na EMI utilizam um transdutor Pb-Lead Zirconate Titanite (PZT ) ligado à estrutura monitorada e medem a assinatura de impedância do PZT. No entanto, as técnicas baseadas na EMI dependem de diferentes fatores, como faixa de frequência, número de PZT, temperatura ambiente, tipo de estrutura, entre outros. Assim, para demonstrar a eficácia dos métodos baseados na EMI, faz-se necessário realizar experimentos práticos, o que não é uma tarefa trivial, considerando tais fatores. Portanto, neste trabalho são estudados e propostos procedimentos para criar modelos numéricos, usando elementos finitos (FE), de técnicas baseadas na EMI usando o software PZFlex®. Além disso, os modelos desenvolvidos são usados para propor uma técnica inovadora de compensação de temperatura em sistemas baseados na EMI. Foram modeladas, simuladas e analisadas algumas estruturas clássicas como placa-de-alumínio/PZT e tubo-de-aço/PZT. Os resultados das simulações foram comparados com os equivalentes obtidos com modelos experimentais reais e mostraram-se fortemente correlacionados, indicando que o modelo proposto pode ser uma ferramenta poderosa para o desenvolvimento de técnicas de SHM baseadas na EMI. Foram realizadas simulações ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The damage detection techniques based on the Electromechanical Impedance (EMI) rely on the ability of piezoelectric materials in acting as sensors and actuators and contribute to the development of Structural Health Monitoring (SHM) systems. The classical EMI-based techniques use a Pb-Lead Zirconate Titanite (PZT) transducer bonded to the monitored structure and measure the impedance signature of the PZT. However, the techniques based on EMI depend on different factors, such as frequency range, number of PZTs, environmental temperature, type of structure, among others. Thus, to demonstrate the effectiveness of EMI-based methods, it is necessary to carry out practical experiments, which is not a trivial task considering such factors. Therefore, in this work, it is studied and proposed procedures to create numerical models of techniques based on the EMI, using finite elements (FE) and the PZFlex® software. In addition, the developed models are used to propose an innovative temperature compensation technique for EMI-based systems. Some classical structures were modelled, simulated and analyzed, such as aluminum plate/PZT and steel pipe/PZT. The results of the simulations were compared with the equivalents obtained by experimental models and showed to be strongly correlated, indicating that the proposed model can be a powerful tool for the development of EMI-based SHM techniques. Simulations were performed to analyze the behavior of the signatures under the effect of temperature,... (Complete abstract click electronic access below) / Doutor

This Critical Review discusses the significance of the author’s published works and their impact on the history of the emergence of British television between 1926 and 1936. Although events in television within this period have since been well-documented, the related debates have tended to be specialist in scope and restricted to technology-centric or institution-centric viewpoints. Within this period of complex, rapid technological change, the author’s published works introduce the principle of embracing multiple disciplines for comparative analysis. The author’s application of that principle opens up long-established views for further debate and provides a re-assessment of early British television within a broader context. The rewards of this approach are a view of events that not only avoids nationalistic bias and restrictions of a single institutional viewpoint, but also tackles the complex inter-dependencies of technology, of service provision and of content creation. These published works draw attention to the revolutionary improvements that enabled the BBC’s 1936 service and the re-definition of television, yet also emphasise the significance of the previous television broadcast services. The most important innovation within these works has been the author’s discovery and in-depth study of artefacts from that earlier period. His recovery, analysis and presentation of video recordings of historic early television from 1927-1935 is original and remains unique. It has had a significant impact on the field of Media Archaeology, where Ernst considers the book Restoring Baird’s Image as a ‘seminal’ work and the overall restoration project ‘a brilliant case of “Digital Humanities” research’ (Appendix 2). The author’s curation of content from the period 1927-1935 enhances our understanding of a time where previously no direct television footage was thought to exist. The author extends his forensic-level investigative ‘hands-on’ techniques from this recovery to the analysis of the surviving artefacts from the time of John Logie Baird’s claimed first demonstration of television in 1926. The results clarify not only the functions of the equipment but also the circumstances and validity of the event, and hence its true place in the history of television.

New textile materials are constantly being brought into the automotive field, and automobile design is a leader in innovative and spectacular developments where smart textile materials are used. The main elements of the current project are textile material research, automotive research, design and development of two upholstery concepts for automotives using smart textiles. The added values are RFI/EMI (Radio Frequency Interference / Electro Magnetic Interference) shielding qualities, light emitting, light reflective and antistatic qualities. Values in the smart-textile area are obtained through choice of material and textile techniques. Transportation textiles are considered high performance technical fabrics, but they must also meet the aesthetic demands of the market. In the current project the design is inspired by Japanese architectural thinking and strives to relate to outdoor environment to reduce the border between indoor and outdoor environment. The inspiration source is water surfaces. The colour setting is also inspired by water surfaces. Material selection is based on the chosen added values, material qualities, appearance and availability. The result of the work is two different upholstery concepts visualizing qualities of smart materials and requests the automotive field. Sprinkle is an upholstery with light emitting, light reflective and antistatic values. The materials used are monofilament, polyester and electroluminescent wires. Wave is an upholstery design with antistatic, light reflective and RFI/Emi shielding qualities. The materials used are stainless steel yarn, rubco and monofilament. / <p>Program: Konstnärligt masterprogram i mode- och textildesign</p><p>Uppsatsnivå: D</p>

La CEM (Compatibilité ElectroMagnétique) est de plus en plus importante dans la conception des systèmes électroniques et plus particulièrement dans le domaine automobile. En effet, avec la densification de l’électronique dans les véhicules, les problèmes liés à la CEM sont de plus en plus fréquents. Ainsi, afin de limiter ces interférences électromagnétiques, des filtres correctement dimensionnés et implémentés doivent être utilisés. Chaque filtre est dimensionné en tenant compte de l’environnement dans lequel il va être introduit. Cependant, de nombreux facteurs peuvent altérer ses performances, tel que le routage, la structure mécanique ou bien les couplages internes au filtre, entre les composants eux-mêmes. Cette thèse traite de l’étude de l’influence des couplages inter-composants sur les performances d’un filtre pour la CEM. En effet, les méthodes existantes sont basées uniquement sur des simulations électromagnétiques 3D qui sont couteuses en terme de temps et requiert également un trop grand nombre d’informations sur les composants (propriétés géométriques, des matériaux etc.). Ainsi, une méthode uniquement basée sur des calculs analytiques et exploitations de mesures a été développée. Cette méthode simplifiée est très efficace car elle permet la prédiction des performances d’un filtre, quelle que soit sa topologie et quelle que soit sa structure. Cette méthode a été validée via de nombreux cas d’applications de filtres implémentés sur des systèmes d’électronique de puissance du domaine automobile. Finalement, cette méthode a été capitalisée au travers d’un outil pour le design et la prédiction des performances de filtre pour la CEM en tenant compte de la proximité des composants. / EMC (ElectroMagnetic Compatibility) is increasingly important in electronic and electrical systems and more particularly in the automotive domain. Actually, there are more and more power electronics equipments in a vehicle and, therefore, EMC issues are more recurrent. In order to limit EMI (ElectroMagnetic Interferences), well designed filters are needed. Each filter is designed corresponding to a system and the required attenuation. However, different parameters can have influence on the filter performances, such as the layout, the mechanical structure or the inter-components coupling of the filter. Therefore, the thesis work is based on the study of the filter performance considering inter-components coupling. Some methods exist on that topic bu are generally based on 3D electromagnetic simulation, which is time-consuming and requires a lot of information on components (geometrical properties, material properties etc.). Therefore, our work is based on a methodology only based on analytical calculation and measurements. That simplified methodology is very accurate because it can predict a filter performance, whatever the filter topology, whatever the structure. That method was validated under several application cases on power electronics systems for automotive domain. Finally, the whole methodology has been accrued in a tool for filter design that can predict a filter attenuation by considering the components proximity.

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