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RDFID tagged snails were used as part of a messaging system in order introduce an element of uncertainty in the the delivery mechanism. One inspiration for the project was the Slow Art movement which aims to make people slow down and think about what they are doing.\ud \ud This project was a collaboration between Boredom Research within the Media School and The Creative technologies Research Group within DEC at Bournemouth University.

As technology improves exciting new services such as video phone become possible and economically viable but their deployment is hampered by the inability of the present networks to carry them. The long term vision is to have a single network able to carry all present and future services. Asynchronous Transfer Mode, ATM, is the versatile new packet -based switching and multiplexing technique proposed for the single network. Interest in ATM is currently high as both industrial and academic institutions strive to understand more about the technique. Using both simulation and analysis, this research has investigated how the performance of ATM switches is affected by architectural variations in the switch fabric design and how the stochastic nature of ATM affects the timing of constant bit rate services. As a result the research has contributed new ATM switch performance data, a general purpose ATM switch simulator and analytic models that further research may utilise and has uncovered a significant timing problem of the ATM technique.\ud The thesis will also be of interest and assistance to anyone planning on using simulation as a research tool to model an ATM switch.

Artificial neural networks have been universally acknowledged for their ability on constructing forecasting and classifying systems. Among their desirable features, it has always been the interpretation of their structure, aiming to provide further knowledge for the domain experts. A number of methodologies have been developed for this reason. One such paradigm is the neural logic networks concept. Neural logic networks have been especially designed in order to enable the interpretation of their structure into a number of simple logical rules and they can be seen as a network representation of a logical rule base. Although powerful by their definition in this context, neural logic networks have performed poorly when used in approaches that required training from data. Standard training methods, such as the back-propagation, require the network’s synapse weight altering, which destroys the network’s interpretability. The methodology in this paper overcomes these problems and proposes an architecture-altering technique, which enables the production of highly antagonistic solutions while preserving any weight-related information. The implementation involves genetic programming using a grammar-guided training approach, in order to provide arbitrarily large and connected neural logic networks. The methodology is tested in a problem from the banking sector with encouraging results.

In some areas, aerobic treatment can deal with different pollution problem, more particularly with the water pollution by nitrate. During treatment, nitrogen is removed as nitrogen gaseous forms by nitrification and denitrification. However, transformations and transfer of nitrogen of the slurry to the atmosphere could be a source of gas pollution (N2O, NH3). Different studies, using a laboratory treatment system, specify the influence of these parameters on nitrogen removal and gaseous emissions during aerobic treatment of slurry. A series of 10 runs carried out in laboratory allowed us to observe a nitrogen removal during aeration from 15 to 66% of the total nitrogen of the raw slurry during aeration. Cumulated nitrogen removal obtained during aeration with the removal from post-storage (10 to 57% of the total nitrogen of the raw slurry), a total nitrogen removal efficiency ranging from 52 to 85% of the total nitrogen of the raw slurry was obtained. The main parameters which influence nitrogen transformations are carbon availability of the raw slurry (BOD) and aeration strategy. For the different aeration strategies, NH3 and NOx emissions are low during aeration ((0.8% of the total nitrogen of the raw slurry) and the main pathways for nitrogen removal are N2 and N2O. The use of labelled nitrogen (15N) allowed to distinguish the N2O production from either nitrification or denitrification. Indeed, during nitrification, nitrite accumulation lead to nitrite reduction to N2O by nitrifiers which caused N2O emissions up to 31% of the total nitrogen of the raw slurry. During denitrification, inhibition of N2O reductase by dissolved oxygen lead also to N2O emissions up to 24% of the total nitrogen of the raw slurry. Result from the current work indicate the importance of the parameters of treatment on the total removal efficiency and the nitrogen gaseous emissions. According to these results, it seems possible to build aerobic treatment systems allowing high level of nitrogen removal without atmospheric gas pollution, particularly with N2O., Le traitement aérobie du lisier est envisagé, dans certaines régions, comme une alternative susceptible de résoudre différents problèmes de pollution, notamment la pollution des eaux par les nitrates. Au cours du traitement, une partie de la charge azotée du lisier est transformée en composés azotés gazeux par nitrification et dénitrification. Cependant, les transformations et le transfert de l'azote du lisier vers l'atmosphère engendrent parfois des émissions de gaz polluants tels que le protoxyde d'azote (N2O) et l'ammoniac (NH3). Différentes études, réalisées à l'aide d'un pilote de laboratoire instrumenté, précisent l'influence des paramètres de fonctionnement sur l'élimination d'azote et sur la production de gaz polluants pendant le traitement aérobie du lisier de porcs. Les essais menés en laboratoire ont permis de mettre en évidence une élimination de 15 à 66% de l'azote total du lisier brut pendant l'aération. En ajoutant le taux d'élimination obtenu pendant la phase d'aération avec celui issu de la phase de stockage (10 à 57% de l'azote total du lisier brut), on atteint des taux d'élimination totale compris entre 52 et 85% de l'azote total du lisier brut. Les principaux paramètres de fonctionnement influençant les transformations sont, la quantité de carbone assimilable du lisier brut (DBO) et la stratégie d'aération. Pour les différentes stratégies de traitement, les émissions de NH3 et NOx sont faibles pendant l'aération (( 0.8% de l'azote total du lisier brut) et les principales voies d'élimination sont le N2 et N2O. L'utilisation du traceur isotopique 15N nous a permis de mettre en évidence le rôle de la nitrification et de la dénitrification sur la production et l'accumulation de N2O. En effet, pendant la nitrification, une accumulation de nitrites entraîne une réduction de ces nitrites en N2O par les bactéries nitrifiantes, ce qui engendre des émissions de N2O représentant jusqu'à 31% de l'azote total du lisier brut. D'autre part, au cours de la dénitrification, l'inhibition partielle de l'enzyme N2OR, par l'oxygène dissous, entraîne une accumulation et des émissions de N2O représentant jusqu'à 24% de l'azote total du lisier brut. Ces travaux soulignent l'importance des paramètres de fonctionnement sur l'efficacité épuratoire globale et sur les formes azotées gazeuses émises dans l'atmosphère. D'après l'ensemble de ces résultats, il apparaît possible de mettre en place des systèmes de traitement aérobie permettant une élimination d'azote importante tout en évitant les transferts de pollution vers l'atmosphère, notamment vis-à-vis du N2O.

This thesis is concerned with the design of multiplier-less (ML) finite impulse response (FIR) digital filters. The use of multiplier-less digital filters results in simplified filtering structures, better throughput rates and higher speed. These characteristics are very desirable in many DSP systems. This thesis concentrates on the design of digital filters with power-of-two coefficients that result in simplified filtering structures. Two distinct classesof ML FIR filter design algorithms are developed and compared \ud with traditional techniques. The first class is based on the sensitivity of filter coefficients to rounding to power-of-two. Novel elements include extending of the algorithm for multiple-bands filters and introducing mean square error as the sensitivity criterion. This improves the performance of the algorithm and reduces the complexity of resulting filtering structures. The second class of filter design algorithms is based on evolutionary techniques, primarily genetic algorithms. Three different algorithms based on genetic algorithm kernel are developed. They include simple genetic algorithm, knowledge-based genetic algorithm and hybrid of genetic algorithm and simulated annealing. Inclusion of the additional knowledge has been found very useful when re-designing filters or refining previous designs. Hybrid techniques are useful when exploring large, N-dimensional searching spaces. Here, the genetic algorithm is used to explore searching space rapidly, followed by fine search using simulated annealing. This approach has been found beneficial for design of high-order filters. Finally, a formula for estimation of the filter length from its specification and complementing both \ud classes of design algorithms, has been evolved using techniques of symbolic regression and genetic programming. Although the evolved formula is very complex and not easily understandable, statistical analysis has shown that it produces \ud \ud more \ud accurate results than traditional Kaiser's formula. \ud \ud In summary, several novel algorithms for the design of multiplier-less digital filters \ud have been developed. They outperform traditional techniques that are used for the \ud design of ML FIR filters and hence contributed to the knowledge in the field of ML \ud FIR filter design. \ud

Los estudios socio-políticos respecto a las conformaciones tecnocráticas en la UE permiten destacar un sistema de gobernanza a la luz de la alianza de clase entre la comunidad epistémica, la clase política clásica, los lobbies económicos y financieros. Esta alianza marca una revolución neo-liberal en la naturaleza del poder y una posición dominante en el proceso histórico hegemónico. En este articulo proponemos la análisis de las dinámicas histórico políticas a través de las cuales, desde la Estrategia de Lisboa, la gobernanza europea construye y expande los mecanismos de subsunción al capital, imponiendo los ajustes y las reformas estructurales que están transformando nuestros modos de vida en ganancia y miseria. The socio-political studies concerning the technocratic conformations in the EU enable the emphasis on a governance system in the light of the class analysis between the epistemic community, the traditional political class, the economic and financial lobbies. This alliance sets a neo-liberal revolution in the nature of power and a dominant position in the hegemonic historical process. In this article we propose the analysis of the historical and political dynamics through which, since the Lisbon Strategy, the european governance constructs and expands the mechanisms of subsumption under capital, imposing the adjustments and the structural reforms that are transforming our lifestyles in greed and misery.

Dynamic reconfiguration of logic circuits has been a research problem for over four decades. While applications using logic reconfiguration in practical scenarios have been demonstrated, the design of these systems has \ud proved to be a difficult process demanding the skills of an experienced reconfigurable logic design expert. This thesis proposes an automatic synthesis method which relieves designers of some of the difficulties associated with designing partially dynamically reconfigurable systems. A new design abstraction model for reconfigurable systems is proposed in order to support design exploration using the presented method. Given an input behavioural model, a technology server and a set of design constraints, the method will generate a reconfigurable design solution in the form of a 3D floorplan and a configuration schedule. The approach makes use of genetic algorithms. It facilitates global optimisation to accommodate multiple design objectives common in reconfigurable system design, while making realistic estimates of configuration overheads and of the potential for resource sharing between \ud configurations. A set of custom evolutionary operators has been developed to cope with a multiple-objective search space. Furthermore, the application of a simulation technique verifying the lll results of such an automatic exploration is outlined in the thesis. The qualities of the proposed method are evaluated using a set of benchmark \ud designs taking data from a real reconfigurable logic technology. Finally, some extensions to the proposed method and possible research directions are discussed.

Optical fibres have been used as a key medium for telecommunication and networking for more than two decades because in principle they offer sufficient transmission capacity, reaching total rates as high as Tbits/s per fibre. Critical fibre properties such as mode field profiles, single-mode propagation conditions and dispersion characteristics can all be related to the optical fibre refractive index profiles. For this reason, it is of fundamental importance to be able to determine the optical fibre refractive index profiles. In this thesis, a novel Transmission-Line technique has been studied and extended \ud for both the forward and inverse solutions. In the forward solution of the Transmission-Line technique, it is shown that the technique is not only capable of determining exactly the propagation constants in optical fibres with real refractive index profiles, but also evaluating accurately the complex propagation constants in single-mode fibres with arbitrary complex refractive index profiles. To illustrate the effectiveness of this technique, it is applied to the evaluation and manipulation of the gain in a typical 980 nm pumped Erbium-Doped fibre as well as to the calculation of the attenuation of optical fibres when radial loss factors are presented. Moreover, based on the Transmission-Line equivalent circuit model, the exact analytical formulas are derived for a recursive algorithm which allows direct and efficient calculation of dispersion of arbitrary refractive index profile optical fibres. The proposed algorithm computes dispersion directly from the propagation constants without the need for curve fitting and successive subsequent numerical differentiation. The algorithm results in savings for both storage memory and computation time. In the inverse solution using the Transmission-Line technique, the optical fibre refractive index profile synthesis from the given mode electric field distribution is developed and demonstrated. The application of the Transmission-Line principles in the study of optical fibre properties was developed for the first time in the early 80's. However, until now the potential of using Transmission-Line technique for the design of optical fibres based on the given electric field pattern had not been examined. From Maxwell's equations, the Transmission-Line equivalent circuits are derived for a homogeneous symmetric optical fibre. This work demonstrates how to \ud use the Transmission-Line model to reconstruct the exact refractive index profile from the electric field data. The accuracy of the reconstructed optical fibre refractive \ud index profile is examined numerically.

This work explores the use of MPQ online facilities within the Blackboard v8 VLE (MyBU)at Bournemouth. It enables tutors to set and administer coursework tests to large cohorts. Initial findings show that students initially engaged beter with the unit, subsequent engagement was poor. Other work suggests better integration between MyBU and Cisco's learning material can improve the stuent experience. Future work will investigate these options.