abstract: Horizontal Directional Drilling (HDD) is a growing and expanding trenchless method utilized to install pipelines from 2 to 60 inch diameters for lengths over 10,000 foot. To date, there are not many public documents where direct costs and bid prices incurred by HDD installations are available and analyzed. The objective is to provide a better understanding of the factors affecting the bid prices of these projects. The first section of the thesis analyzes how project parameters such as product diameter, bore length and soil conditions affect the bid price of water and wastewater pipeline installations using HDD. Through multiple linear regressions, the effect of project parameters on bid prices of small, medium and large rigs projects is extracted. The results were further investigated to gain a better understanding of bid factors that influence the relationship between total cost and the project parameters. The second section uses unit cost, based on bid prices, to compare the costs incurred by defined categories. Parameters such as community type, product type, soil conditions, and geographical region were used in the analysis. Furthermore, using average unit cost from 2001 to 2009, HDD project cost trends are briefly analyzed against the main variations of the US economy from the same time horizon by using economic indicators. It was determined that project geometric factors influence more the bid price of small rig projects than large rig projects because external factors including market rates and economic situation have an increasing impact on bid prices when rig size increases. It was observed that bid price variation of HDD projects over years followed the same trend as the US economic variation described by economic indicators. / Dissertation/Thesis / M.S. Construction 2010

This thesis has contributed to the design of suitable decision-making techniques for energy management in the smart grid with emphasis on energy efficiency and uncertainty analysis in two smart grid applications. First, an energy trading model among distributed microgrids (MG) is investigated, aiming to improve energy efficiency by forming coalitions to allow local power transfer within each coalition. Then, a more specific scenario is considered that is how to optimally schedule Electric Vehicles (EV) charging in a MG-like charging station, aiming to match as many as EV charging requirements with the uncertain solar energy generation. The solutions proposed in this thesis can give optimal coalition formation patterns for reduced power losses and achieve optimal performance for the charging station. First, several algorithms based on game theory are investigated for the coalition formation of distributed MGs to alleviate the power losses dissipated on the cables due to power transfer. The seller and buyer MGs can make distributed decisions whether to form a coalition with others for energy trading. The simulation results show that game theory based methods that enable cooperation yield a better performance in terms of lower power losses than a non-cooperative approach. This is because by forming local coalitions, power is transferred within a shorter distance and at a lower voltage. Thus, the power losses dissipated on the transmission lines and caused by power conversion at the transformer are both reduced. However, the merge-and-split based cooperative games have an inherent high computational complexity for a large number of players. Then, an efficient framework is established for the power loss minimization problem as a college admissions game that has a much lower computational complexity than the merge-and-split based cooperative games. The seller and buyer MGs take the role of colleges and students in turn and apply for a place in the opposite set following their preference lists and the college MGs’ energy quotas. The simulation results show that the proposed framework demonstrates a comparable power losses reduction to the merge-and-split based algorithms, but runs 700 and 18000 times faster for a network of 10 MGs and 20 MGs, respectively. Finally, the problem of EV charging using various energy sources is studied along with their impact on the charging station’s performance. A multiplier k is introduced to measure the effect of solar prediction uncertainty on the decision-making process of the station. A composite performance index (the Figure of Merit, FoM) is also developed to measure the charging station’s utility, EV users charging requirements and the penalties for turning away new arrivals and for missing charging deadlines. A two-stage admission and scheduling mechanism is further proposed to find the optimal trade-off between accepting EVs and missing charging deadlines by determining the best value of the parameter k under various energy supply scenarios. The numerical evaluations give the solution to the optimization problem and show that some of the key factors such as shorter and longer deadline urgencies of EVs charging requirements, stronger uncertainty of the prediction error, storage capacity and its initial state will not affect significantly the optimal value of the parameter k.

O presente trabalho está focado no método de perfuração direcional horizontal (HDD) para instalação de redes de esgoto gravitacional. Descrevem-se os resultados de diferentes técnicas com o objetivo de se atingir a exigência de declividade. Para tanto foram executados 4 furos experimentais simulando trechos daquelas redes, com extensão de 30 m e tubulação de PEAD com diâmetro externo de 125 mm. Estas instalações foram executadas na cidade de São Carlos, Brasil, em um solo classificado granulometricamente como uma areia argilosa. Para cada uma das 4 instalações, adotou-se um processo construtivo diferenciado. Esta diferenciação se deu a partir do diâmetro do alargador adotado, do número de passadas do mesmo e da execução de furos verticais para alívio de pressão no espaço anelar assim como medidas diretas de profundidade do furo piloto. Após a instalação dos dutos foram realizadas medidas altimétricas no interior dos mesmos possibilitando avaliar quantitativamente os resultados obtidos. Estes resultados indicam que ainda é necessário refinar a técnica de perfuração direcional para a execução das redes de esgoto. Entretanto é possível observar que as variações empregadas na execução de cada um dos furos conduzem a um caminho de melhoria nos resultados obtidos. Esta melhoria pode ser observada nos furos onde o alargador adotado apresentava menor diâmetro conduzindo a menores desvios na posição final do duto. Salientam-se também os benéficos resultados da execução dos furos verticais que conduziram a menores pressões no espaço anelar assim como possibilitaram medidas altimétricas diretas da posição do furo piloto. Desta forma, é provável que com um maior número de experimentos e incrementos tecnológicos se atinja o objetivo final, ou seja, executar redes de esgoto gravitacional com declividade constante e baixa. Em paralelo nas instalações executadas foram realizados testes para avaliação da precisão e acurácia do sistema de navegação responsável pelo fornecimento de informações de posição e temperatura da ferramenta de corte durante a execução do furo piloto. Este trabalho contempla ainda, a elaboração de uma nova solução para as instalações de esgoto executadas através do HDD. Esta solução propõe a aplicação de um esforço de tração a um elemento externo, uma geogrelha que envolve a tubulação, visando posicionar a mesma em declividade constante. Face a seu caráter inovador foram desenvolvidos equipamentos e procedimentos de ensaio de laboratório, para avaliar a aplicabilidade da solução na prática / The present work is focused on the horizontal directional drilling (HDD) method to install gravity sewers. The results of different techniques are described intending to meet the demands of gradient. Therefore, 4 experimental pilot bores were drilled simulating a section of those structures extending 30 m with HDPE pipelines of 125 mm external diameter. Those installations were engineered in the city of São Carlos, Brazil, in a clayey sand. For each of the 4 installations a distinct constructive process was adopted. Such characteristic was on account of the diameter of the selected reamer, the number of reamer steps and the vertical drills performed to relieve the pressure in the annular space, as well as the direct depth measurements of the pilot hole. After installing the pipes, altimetric measurements were performed inside them, hence enabling to quantitatively assess the obtained results. These results indicate the need to further refine the directional drilling technique for sanitary sewers. Yet it can be seen that the employed variations for each of the holes lead to an improved course of action with the observed results. Such improvement is perceived in the holes where the selected reamer had a smaller diameter, hence allowing for less displacement in the pipes final position. Also emphasized are the resulting benefits of the vertical drills that lead to less pressure in the annular space, as well as enabling altimetric measurements of the pilot hole position. Thus, it is presumed that with further experiments and technological developments the final objective is reached, meaning, putting into effect constant and low level gradient sewer networks. Tests for precision and accuracy assessment of the tracking system were also performed in each tube installed. The tracking system is responsible for providing information related to position and temperature of the drill head during the drilling operation. The steps for the development of a new HDD solution for sewer installation are presented. The idea is based on the application of a tensile force to an element external to the product, aiming at attaining a constant gradient. Equipments and procedures developed for this new technique are described.

Os sistemas que elevam os eixos dos veículos comerciais foram inicialmente desenvolvidos com o objetivo de economizar pneus. Até o final da década de 90, o uso destes sistemas era restrito, não causando um efeito estatístico sensível na segurança veicular. Devido a um acordo entre concessionárias rodoviárias e o governo, os veículos comerciais pagam nas praças de pedágio o valor correspondente ao número de eixos em contato com o solo naquele momento, minimizando as tarifas dos veículos que fazem uso deste sistema. Esta prática se difundiu rapidamente e poucos estudos técnicos foram realizados focando sua influência na segurança veicular. A elevação dos eixos altera de forma significativa a margem de estabilidade do veículo e a distribuição ideal das forças de frenagem, podendo elevar os riscos de acidentes. Este trabalho consiste num estudo aprofundado do desempenho dos veículos comerciais com estes sistemas de elevação de eixos, sob o ponto de vista técnico e operacional, focando a segurança veicular. Para tanto, são utilizados como metodologia modelos matemáticos já desenvolvidos na literatura científica em veículos exemplos. Parâmetros como a margem de estabilidade, gradiente de esterçamento, eficiência da frenagem dentre outros são analisados; também os efeitos na resposta direcional durante o período transitório em manobras e nos instantes iniciais da frenagem. As influências da elevação dos eixos são analisadas conforme normas e requisitos estabelecidos pela ABNT e ECE R13, inclusive anexo 10, pois a prática da elevação dos eixos pode estar infringindo requisitos impostos por estas normas. Como conclusão é visto que o levantamento dos eixos é prejudicial ao desempenho dinâmico do veículo. Em virtude disto, o seu uso deveria ser fundamentado tanto nas fases conceitual e de desenvolvimento quanto na legislação vigente no país. / The systems that elevate the axles of the commercial vehicles were initially developed with the objective of saving tires. The use of these systems was restricted, not causing a notable statistical effect in the vehicle safety. Due to an agreement between road concessionaires and the government, the commercial vehicles pay toll value according to the number of axles in contact with the soil on that moment, minimizing the taxes of the vehicles using this system. This practice was diffused quickly and few technical studies were accomplished focusing its influence in the vehicle safety. The elevated axles alters in a significant way the vehicle static margin of stability and the ideal distribution of the braking forces, increasing the accident risks. This work consist in deepened studies of the commercial vehicles with these systems of elevation of axles, of the technical and operational point of view, focusing the vehicle safety. For this is used as methodology mathematical models developed already in the scientific literature in vehicles examples. Parameters as the margin of stability, steer gradient, braking efficiency and others are analyzed. Likewise, the effects in the directional response during the transient maneuvers and in the initial instants of the braking. The influences of the elevation of the axes are analyzed according to norms and established requirements for ABNT and ECE R13, including annex 10, because the practice of the elevation of the axes can be infringing requirements imposed by these norms. As main conclusion these systems are prejudicial to vehicle dynamics and handling and its use could be anticipated in conceptual and design phase and in brazilian transport laws.

As industry becomes increasingly reliant on robotic assistance and human-computer interfaces, the demand to understand the human sensorimotor system’s characteristics intensifies. Although this field of research has been going on for over a century, new technologies push the limits of the human motor system and our knowledge of it. With new technologies come new abilities, and, in the area of medical care and rehabilitation, the need to expand our knowledge of the sensorimotor system comes from both the patient and physician. Two studies relating to human force interaction are presented in this thesis. The first study focuses on humans’ ability to bimanually recreate forces. That is, to feel a force on one hand and reproduce that force on the other. This skill is applicable in everyday lives from tasks such as a gardener using shears to trim a bush to a surgeon tying a delicate suture. These two tasks illustrate the different factors in this study on force recreation, which are the effects of: (1) occupational force dexterity, (2) force magnitude, and (3) the number of fingers used in the recreation task. Results showed statistical significance for force magnitude and number of fingers as factors in bimanual force recreation but not for occupation. The second study examines how humans compensate for force perturbations in different directions with respect to the line of action and the effects of restricting movement time. A dynamic tracking task was presented to participants in which they were told to follow a moving target as accurately as possible. During a fixed interval along the target’s path, a force field would perturb them in an undisclosed direction. Nine force conditions and three speeds were tested on both the left and right hands. Statistical analyses and comparison of error data indicate an effect of force direction on compensation accuracy. Speed is demonstrated as a statistically significant factor on accuracy, and a linear relationship between speed and error is posited.

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This thesis is based on a project "Bifacial Photovoltaic Energy Production Analysis" to build a detailed simulation model system accurately simulate bifacial panel performance under real field radiation conditions and deployment configuration, and to predict its corresponding energy yield. To the author’s up-to-date knowledge, the model system is unpreceded among same type simulation software in complexity, details in consideration, ranges of deployment and parameters. The model system can also be used as a platform for more components and variables to be added on, such as adding on more rows of panel arrays to simulate bifacial solar farm scenario; and adding spectral information for more accurate analysis. The system components’ sub-models were carefully chosen based on a broad literature review in related aspects; especially in sky diffuse radiance, ground reflection, and bifacial solar cells. Built in MATLAB© based on mathematical expressions from above said models, the system consists of 5 bifacial panels and their racking as shading objects and the central panel performance is under investigation and has taken consideration of all possible panel azimuth and elevation combinations. Model simplification and resolution are carefully considered so to achieve a good balance in complexity, computation load and output accuracy. Output reliability is confirmed with other people’s work. Furthermore, the model has been fully checked and peer tested. Outputs under different parameter settings are analysed and discussed. Conclusions and recommended future work are provided at the end of the thesis.

Sistemas morfológicos quantitativos são descritos por medidas contínuas. A relação genética entre essas características dos indivíduos é representada pela matriz de covariância genética aditiva, a matriz G. Entender a evolução da matriz G, portanto, é de suma importância para compreender os padrões de diversificação encontrados na natureza. Neste trabalho estudamos modelos computacionais para a evolução de traços contínuos em populações naturais, sujeitas a variados tipos de seleção e condições internas, focando no problema da evolução dos padrões de integração e modularidade nessas populações. Testamos dois modelos com diferentes combinações de parâmetros em sua capacidade de reproduzir e elucidar padrões naturais. Seleção direcional correlacionada se mostrou uma força importante na criação desses padrões de covariação e a seleção estabilizadora correlacionada se mostrou fundamental para a manutenção desses padrões / Quantitative morphological systems are described by continuous measurements. The genetic relation between these characteristics of the individuals is represented by the genetic additive co-variance matrix, the G matrix. Understanding the evolution of the G matrix is, therefore, of paramount importance for proper interpretation of the patterns of diversification we observe in nature. In this work we study computational models for the evolution of quantitative traits in natural populations, subject to different natural selection and internal conditions, focusing on the problem of the evolution of the pattern of morphological integration and modularity. We test two models with different sets of parameters in their ability to reproduce and elucidate natural patterns. Directional correlated selection was necessary for the shaping of the patterns of morphological integration, and correlated stabilizing selection was fundamental to the maintenance of these patterns

At present, there is a widespread use of alternative measurement technologies in electrical networks that include current and voltage sensors. Their use is closely related to the use of IEC 61850-9-2 for data transfer of measured values within the substation for the purpose of protection and measurement. The use of sensors and communication standard IEC 61850 together with high-speed Ethernet will simplify the concept of the arrangement of protection terminals in substations and enable the development of a new protection system based on central protection. The dissertation is focused on protection algorithms, which use the SV according to IEC 61850-9-2, and their implementation into the central protection model. Thesis describes development in the field of protection of substations and the currently available solutions using IEC 61850-9-2 and the principle of central protection. Thesis explains algorithms for selected protection functions - overcurrent protection, negative sequence overcurrent protection, logic busbar protection and differential protection. Further, thesis deals with the programming of protection function algorithms in LabView development environment in the form of a central protection model. The model processes data from a process bus according to IEC 61850-9-2 and sends a GOOSE message over Ethernet in the event of a failure. To verify the correct function of the programmed protection algorithms, a testing procedure was developed using OMICRON 256plus, the current sensor and the merging unit. The results of the testing of the central protection model and the proposed algorithms were compared with the results of testing the currently used protections. At the end, the thesis deals with the assessment of the benefits of central protection for protecting substations and the possibility of further utilization of the central protection model. The thesis highlights a new way of protecting the electrification system using digital data from MU transferred via the process bus described in IEC 61850-9-2.