Dagens samtida konflikter skiljer sig ganska markant ifrån den typ av krigsföring som vi är vana att se den, exempelvis under andra världskriget där reguljära förband stred mot varandra med de allierade på ena sidan fronten och axelmakterna på den andra. I dagens konflikter är nyttjandet av irreguljära förband vanligt förekommande vilket har lett till att reguljära förband måste strida på helt andra villkor och omständigheter än förut. Under Vietnamkriget startades Operation Fenix i syfte att bemöta denna nya typ av krigsföring och de metoder som användes av den amerikanska underrättelsetjänsten var något som inte hade prövats tidigare. Tyvärr gav dessa metoder inte det underrättelsevärde som det var tänkt till en början men frågan står fortfarande kvar hur dessa metoder påverkade VCIs (Viet Cong Infrastructure)  krigföringsförmåga. Syftet med denna uppsats är att i en fallstudie granska om de metoder som Operation Fenix använde under Vietnamkriget var effektiva gentemot irreguljära styrkor samt om det finns något stöd gentemot dessa metoder i militärteorin. I uppsatsen används en teoriprövande fallstudie där David Galulas teorier implementeras i ett analysverktyg skapat utav de tre pelarna i krigföringsförmågor där varje faktor analyseras och slutligen sammanfogas till resultat till den givna frågeställningen. Denna uppsats visar på att de effekter Operation Fenix hade på de irreguljära moståndarna har ett visst samband med de teorier David Galula skapat gällande Counterinsurgency Warfare.

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This thesis describes the investigations undertaken to produce a novel hybrid optimisation technique that combines both global and local searching to produce good solutions quickly. Many evolutionary computation and experimental design methods are considered before genetic algorithms and evolutionary operation are combined to produce novel optimisation algorithms. A novel piece of software is created to run two and three factor evolutionary operation experiments. A range of new hybrid small population genetic algorithms are created that contain evolutionary operation in all generations (static hybrids) or contain evolutionary operation in a controlled number of generations (dynamic hybrids). A large number of empirical tests are carried out to determine the influence of operators and the performance of the hybrids over a range of standard test functions. For very small populations, twenty or less individuals, stochastic universal sampling is demonstrated to be the most suitable method of selection. The performance of very small population evolutionary operation hybrid genetic algorithms is shown to improve with larger generation gaps on simple functions and on more complex functions increasing the generation gap does not deteriorate performance. As a result of the testing carried out for this study a generation gap of 0.7 is recommended as a starting point for empirical searches using small population genetic algorithms and their hybrids. Due to the changing presence of evolutionary operation, the generation gap has less influence on dynamic hybrids compared to the static hybrids. The evolutionary operation, local search element is shown to positively influence the performance of the small population genetic algorithm search. The evolutionary operation element in the hybrid genetic algorithm gives the greatest improvement in performance when present in the middle generations or with a progressively greater presence. A recommendation for the information required to be reported for benchmarking genetic algorithm performance is also presented. This includes processor, platform, software information as well as genetic algorithm parameters such as population size, number of generations, crossover method and selection operators and results of testing on a set of standard test functions.

The aim of this thesis is to develop an integrated methodology for investigating the potential for new local railway stations within a given area, with particular emphasis on the use of Geographical Information Systems (GIS). Existing methods for assessing the case for constructing new local railway stations have often been found wanting, with the forecasts produced proving to be inaccurate. A review of previous work in this field has been undertaken and methodologies with the potential to enhance local rail demand models have been identified. Trip rate and trip end models have been developed which are capable of forecasting usage at new station sites anywhere in England and Wales. Geographically Weighted Regression (GWR) has been used to enhance the performance of these models and to account for local variations in the effects of explanatory variables on rail demand. Flow level models have been produced for stations in South-East Wales, with a range of model formulations tested. A survey of ultimate passenger trip origins and destinations was carried out in the same area, enabling the accuracy of theoretical station catchment definition methods to be tested. A GIS-based procedure for locating potential sites for new railway stations within a given area has been developed. This was combined with the results from the demand models and estimates of associated costs and benefits to give a synthesised appraisal procedure capable of assessing the case for constructing particular stations. This procedure was applied to 14 sites in South-East Wales and, along with trip end forecasts for 421 sites across the country, this indicated that there is almost certainly a positive case for constructing a significant number of new railway stations in the UK.

Pandrol Rail Fastenings Limited are a designer and manufacturer of railway rail-fastening systems. As an organisation they have the capability to reduce the noise impact of bridges using resilient track components. They also have a commercial interest in providing such technology. Knowledge of the processes behind bridge noise is important to Pandrol in two ways; to aid the engineers within the organisation in the design of fastening systems and to demonstrate a state-of-the-art understanding of the problem of railway bridge noise to customers, as this will aid in the sale of Pandrol products. The fitting of new rail components to an existing track form, or failure to meet noise regulations with a new track form, can be costly. It is important to be able to predict accurately the effectiveness of noise reduction techniques. Currently, Pandrol’s knowledge of the problem consists almost entirely of experience gained and data gathered while working on existing bridge projects. To expand their knowledge base, Pandrol perform noise and vibration measurements on railway bridges and viaducts and then use the measured data to predict the performance of their systems on other bridges. This completely empirical approach to predicting bridge noise is both costly and situation specific results cannot be provided before the installation of the fastening system. ii Another approach to predicting bridge noise is through the application of analytical models. Limited analytical modelling in the context of bridge noise is currently conducted within the organisation. For these reasons, Pandrol are sponsoring research into bridge noise in the form of this EngD project. Here an existing rapid calculation approach is identified that relies less on the exact geometry of the bridge and more on its general characteristics. In this approach an analytical model of the track is coupled to a statistical energy analysis (SEA) model of the bridge. This approach forms a suitable basis from which to develop a better model here by concentrating on its weaknesses. A mid-frequency calculation for the power input to the bridge via a resilient track system has been developed by modelling the track-bridge system as two finite Timoshenko beams continuously connected by a resilient layer. This has resulted in a power input calculation which includes the important effects of coupling between the rail and bridge and the resonance effects of the finite length of a bridge. In addition, a detailed study of the frequency characteristics of deep I-section beams has been performed using Finite Element, Boundary Element and Dynamic stiffness models. It is shown that, at high frequencies, the behaviour of the beam is characterised by in-plane motion of the beam web and bending motion in the flange. This knowledge has resulted in an improved calculation for the mobility of a bridge at high frequencies. The above improvements are included in an improved model for use by Pandrol in their general activities. Data from real bridges is compared to predictions from the improved model in order to validate different aspects of the model. The model is then used to study the effect on noise of varying many bridge design parameters. It is shown that the parameter that has most influence on the noise performance of a bridge is the dynamic stiffness of the resilient rail fastening system. Additionally it is demonstrated that for a given bridge and noise receiver location, an optimum fastener stiffness exists where the noise radiated by the bridge and track is at a minimum.

The noise level associated with a train travelling on a bridge is normally greater than that for a train travelling on plain track. It is sometimes the bridge noise that causes the highest levels of disturbance to people in the vicinity or triggers action under regulations such as the Environmental Noise Directive. Consequently, there is a need to study means of predicting noise levels from proposed bridges, noise control measures for existing structures and principles of low-noise bridge design. This thesis describes a programme of work in which an existing calculation model for bridge noise and vibration has been tested and alternative calculation methods have been developed where required. The existing model is based on analytical models for wheel-rail interaction and the calculation of the power input to the bridge. The response of the various component parts of the bridge for this power input is found using a simplified SEA scheme. In this work, the existing model has been tested against measurements made on railway bridges and the results of an advanced method of structural analysis, the Waveguide Finite Element (WFE) method. This method is well-suited to modelling some important types of railway bridge. Specifically, it allows a numerical modelling approach to be used up to higher frequency than conventional Finite Element methods. It has been found to offer some significant advantages over the existing bridge noise model, particularly for concrete-steel composite bridges and concrete box-section viaducts. The track support structure has an important influence on bridge noise and vibration, through its role in the transmission of vibration from the rail to the bridge. Laboratory measurements have been made in this work to characterise the vibration transmission properties of two important types of track support structure on bridges; ballasted track and two-stage resilient baseplate track. Improved methods of modelling the dynamic behaviour of these track forms have been developed from the measurements, which can be used in calculation models for both bridge noise and also for rolling noise.

The prediction of wheel wear is a significant issue in railway vehicles. It is correlated with safety against derailment, economy, ride comfort, and planning of maintenance interventions, and it can result in delay, and costs if it is not predicted and controlled in an effective way. However, the prediction of wheel and rail wear is still a great challenge for railway systems. Therefore, the main aim of this thesis is to develop a method for predicting wheel wear using artificial neural networks. Initial tests were carried out using a pin-on-disc machine and this data was used to establish how wear can be measured using an Alicona profilometer. A new method has been developed for detailed wheel wear and rail wear measurements using ‘Replica’ material which was applied to the wheel and rail surfaces of the test rig to make a copy of both surfaces. The replica samples were scanned using an optical profilometer and the results were processed to establish wheel wear and rail wear. The effect of load, and yaw angle on wheel wear and rail wear were examined. The effect of dry, wet, lubricated, and sanded conditions on wheel wear and rail wear were also investigated. A Nonlinear Autoregressive model with eXogenous input neural network (NARXNN) was developed to predict the wheel and rail wear for the twin disc rig experiments. The NARXNN was used to predict wheel wear and rail wear under deferent surface conditions such as dry, wet, lubricated, and sanded conditions. The neural network model was developed to predict wheel wear in case of changing parameters such as speed and suspension parameters. VAMPIRE vehicle dynamic software was used to produce the vehicle performance data to train, validate, and test the neural network. Three types of neural network were developed to predict the wheel wear: NARXNN, backpropagation neural network (BPNN), and radial basis function neural network (RBFNN). The wheel wear was calculated using an energy dissipation approach and contact position on straight track. The work is focused on wheel wear and the neural network prediction of rail wear was only carried out in connection with the twin disk wear tests. This thesis examines the effect of neural network parameters such as spread, goal, maximum number of neurons, and number of neurons to add between displays on wheel wear prediction. The neural network simulation results were implemented using the Matlab program. The percentage error for wheel and rail wear prediction was calculated. Also, the accuracy of wheel and rail wear prediction using the neural network was investigated and assessed in terms of mean absolute percentage error (MAPE). The results reveal that the neural network can be used efficiently to predict wheel and rail wear. Further work could include rail wear and prediction on a curved track.

This diploma thesis is focused on cutting operation, particularly on turning. The theoretical part defines basic notion of cutting operation. It is especially focused on cutting operation in a broader context and in relation to economy.The practical part is focused on tools for turning, materials which the tools are made of and on the appropriateness of their use for different types of procedures and machined materials. The base of diploma thesis consists of a detailed analysis of selected turning operations in practice often associated with complications. This part contains a detailed analysis of the causes of emerging problems and proposed some solutions based on practical experience. The whole text is didactically conceived to be usable in teaching.

VIDAL, Maria Rita. Geoecologia das paisagens: fundamentos e aplicabilidades para o planejamento ambiental no baixo curso do Rio Curu-Ceará-Brasil. 2014. 121 f. Tese (Doutorado em Geografia)-Universidade Federal do Ceará, Fortaleza, 2014. / Submitted by Vitor Campos (vitband@gmail.com) on 2016-10-18T21:27:46Z No. of bitstreams: 1 2014_tese_mrvidal.pdf: 17575459 bytes, checksum: d12d5a2f4d723cb5d80f1913aa49b4a5 (MD5) / Approved for entry into archive by Jairo Viana (jairo@ufc.br) on 2016-10-19T19:34:43Z (GMT) No. of bitstreams: 1 2014_tese_mrvidal.pdf: 17575459 bytes, checksum: d12d5a2f4d723cb5d80f1913aa49b4a5 (MD5) / Made available in DSpace on 2016-10-19T19:34:43Z (GMT). No. of bitstreams: 1 2014_tese_mrvidal.pdf: 17575459 bytes, checksum: d12d5a2f4d723cb5d80f1913aa49b4a5 (MD5) Previous issue date: 2014 / The thesis deals with the analysis of the dynamics of the landscape as a means for the environmental planning to use and occupate the APA (Environmental Protection Area) in the Estuary of Curu River and its surroundings, situated on the west coast of Ceará.The lack of environmental planning and the mismatch between the APA and ways of using this limited space led to the thesis to raise the proposal of redefinition of the APA limits so that it can encompass important environments for the functioning of landscapes. Making use of theoretical and methodological concepts of geoecology of landscapes, we have adopted the proposal of Rodriguez, Silva and Cavalcanti (2004), who emphasize on the structure and functioning of landscapes. As a result there is the existence of a landscape mosaic, with differences and specific characteristics in its geoecological structure. In determining the state, degradation and geoecological situation of the APA, the study showed that only 20% of goecological units are grouped in stable environmental state without any degradation and in favorable geoecological situation. The rest of the landscapes that make up the APA had shown unfavorable state and geoecological situation, which covers 80% of the studied landscapes, featuring unsatisfactory conditions to meet the environmental functions of those landscapes. The uses and occupations in the APA do not correspond with ground potential, and we have not observed forms of organization of using to ensure the optimization of the employment of the fundamental properties, structures and potential of landscapes. / A tese trata da análise da dinâmica do conjunto paisagístico como meio para o planejamento ambiental do uso e ocupação da APA (Área de Proteção Ambiental) do Estuário do Rio Curu e seu entorno, situada no litoral Oeste do Estado do Ceará. A inexistência de planejamento ambiental e o desencontro entre a APA e as formas de usos nesse espaço delimitado, levou a tese a fazer a proposta de redefinição dos limites da APA para que esta possa englobar ambientes importantes para o funcionamento das paisagens. Fazendo uso das concepções teórico-metodológicas da geoecologia das paisagens, adotou-se a proposta de Rodriguez, Silva e Cavalcanti (2004), com ênfase na estrutura e funcionamento das paisagens. Como resultados tem-se a existência de um mosaico de paisagem, com diferenças e particularidades específicas na sua estrutura geoecológica. Na determinação do estado, degradação e situação geoecológica da APA, o estudo mostrou que apenas 20% das unidades geoecológicas agrupam-se em estado ambiental estável sem degradações e com situação geoecológica favorável. O restante das paisagens que compõem a APA apresentou estado e situação geoecológica desfavorável, o qual abarca 80% das paisagens estudadas, caracterizando condições insatisfatórias para o cumprimento das funções ambientais dessas paisagens. Os usos e ocupações na APA não correspondem ao potencial do solo, e não se observam formas de organização de uso que garantam a otimização do aproveitamento das propriedades fundamentais, das estruturas e das potencialidades das paisagens.

Em virtude da grande proporção das falhas humanas em relação ao número total de falhas, dos gargalos de fornecimento de energia elétrica e do histórico de falhas humanas ocorridas nos últimos anos no sistema elétrico brasileiro, a análise da confiabilidade humana é relevante para o setor elétrico para o aumento da confiabilidade e mitigação da ocorrência de corte de fornecimento de energia aos consumidores. Nesse contexto, esse trabalho objetiva aplicar uma metodologia existente para analisar a probabilidade de ocorrência de falha humana em uma subestação de energia elétrica. Aborda o assunto inicialmente revisando a evolução do cenário de falhas humanas, desde o período da Guerra Fria (1945 a 1989), quando se realizaram os primeiros estudos, até o atual momento, para contextualizar a necessidade de atualização dos conhecimentos sobre confiabilidade humana. No referencial teórico, compilaram-se as conceituações dos diversos métodos utilizados para realização da análise da confiabilidade humana e os fatores que exercem influência sobre o desempenho do operador na execução das tarefas. Elaborou-se uma tabela com o objetivo de propiciar a comparação entre os diversos métodos com suas vantagens e desvantagens. Na sequência, faz-se a apresentação da metodologia para análise da confiabilidade humana, com a definição do cenário crítico, análise dos fatores que exercem influência sobre o desempenho dos operadores e estruturação e análise da árvore de decisão holística com os possíveis valores de probabilidade de ocorrência de erros humanos. Os resultados de sua aplicação em uma subestação do setor elétrico localizada no Estado de Mato Grosso indicaram um valor inicial de probabilidade de ocorrência de erro humano para o cenário analisado. O resultado da pesquisa demonstra qualitativa e quantitativamente quais fatores exerceram mais influência sobre o desempenho humano para esse cenário. Verificou-se que ações para melhoria dos níveis de qualidade dos fatores de desempenho avaliados negativamente, reduzem significativamente a probabilidade de ocorrência de erro humano. Com a determinação da probabilidade de erro humano e dos fatores que exercem influência sobre o operador para sua ocorrência, esta metodologia poderá ser aplicada como ferramenta adicional de gestão do processo de prevenção de falhas humanas e aumento da confiabilidade do setor elétrico. / Due to the large proportion of human failures in relation to the total number of failures, the restrictions in the supply of electric power and the history of human failures in recent years in the Brazilian electricity system, human reliability is relevant for the electric sector to increase the reliability and mitigation of the occurrence of power outages to consumers. In this context, this work aims to apply an existing methodology to analyze a probability of occurrence of human failure in an electric power substation. It addresses the subject initially by reviewing the evolution of the scenario of human failings, from the period of the Cold War (1945 to 1989), when the first studies were carried out, to date, to contextualize the need to update knowledge about human reliability. The theoretical framework supported the compile the concepts of the various methods used to perform the human reliability analysis and the factors that influence the performance of the operator in the execution of the tasks. A table that compares the more relevant methods presents the advantages and disadvantages of each one. Afterwards, the methodology for analysis of human reliability is presented, with the definition of the critical scenario, analysis of the factors that influence the performance of the operators, and the structuring and analysis of the holistic decision tree with the possible probability of occurrence of human errors. The results of its application in a substation of the electric sector located in the State of Mato Grosso indicated an initial probability of occurrence of human error for the analyzed scenario. The results of the research demonstrate qualitatively and quantitatively which are the factors that exerted the most influence on human performance for the scenario. Actions to improve the quality levels of the performance factors evaluated negatively reduce significantly the probability of occurrence of human error. With the determination of the probability of human error and which are the factors that influence the operator for its occurrence, this methodology can be an additional tool to manage the process of human error prevention and increase the reliability of the electric power system.