Many environments are inaccessible or hazardous for humans. Remaining debris after earthquake and fire, ship hulls, bridge installations, and oil rigs are some examples. For these environments, major effort is being placed into replacing humans with robots for manipulation purposes such as search and rescue, inspection, repair, and maintenance. Mobility, manipulability, and stability are the basic needs for a robot to traverse, maneuver, and manipulate in such irregular and highly obstructed terrain. Hexapod walking robots are as a salient solution because of their extra degrees of mobility, compared to mobile wheeled robots. However, it is essential for any multi-legged walking robot to maintain its stability over the terrain or under external stimuli. For manipulation purposes, the robot must also have a sufficient workspace to satisfy the required manipulability. Therefore, analysis of both workspace and stability becomes very important. An accurate and concise inverse kinematic solution for multi-legged robots is developed and validated. The closed-form solution of lateral and spatial reachable workspace of axially symmetric hexapod walking robots are derived and validated through simulation which aid in the design and optimization of the robot parameters and workspace. To control the stability of the robot, a novel stability margin based on the normal contact forces of the robot is developed and then modified to account for the geometrical and physical attributes of the robot. The margin and its modified version are validated by comparison with a widely known stability criterion through simulated and physical experiments. A control scheme is developed to integrate the workspace and stability of multi-legged walking robots resulting in a bio-inspired reactive control strategy which is validated experimentally.

Esta pesquisa explorou a controvérsia existente entre o meio empresarial e o meio acadêmico no tocante à utilização do EBITDA. Alguns autores acadêmicos apontam que este indicador tem pouca utilidade a não ser para comparar empresas de um mesmo segmento; por outro lado, o meio empresarial, utiliza fortemente o indicador para vários propósitos. Esta diferença de opiniões despertou o interesse em entender as razões dos dois lados e, em um aprofundamento maior, observar a utilidade do EBITDA em comparar empresas de um mesmo setor e em setores diferentes. Muito se escreveu sobre a utilidade que o indicador possui na comparação entre empresas, entretanto, ainda não se havia verificado, e tampouco se observado estatisticamente, como os números se comportam de fato. Este trabalho se propôs a estudar a questão sob prisma estatístico. A metodologia utilizada por esta pesquisa, HLM, Hierarchical Linear Modeling. Este método, se comparado aos métodos de regressão clássica é uma elevação, uma vez que é capaz de decompor as variâncias de cada fator. O objetivo maior deste trabalho seria, portanto, observar os comportamentos dos EBITDAs de empresas de um mesmo setor e setores diferentes, ao longo do tempo. As respostas que seriam obtidas poderiam indicar se de fato o indicador pode ser útil (ou não) para a comparação de empresas similares que atuem em um mesmo setor e como o a diferença entre setores era percebida. Os resultados desta pesquisa mostraram que há uma variabilidade significativa do EBITDA entre firmas de um mesmo setor. O mesmo não aconteceu para a variabilidade entre os setores diferentes, ou seja, há diferenças no EBITDA, ao longo do tempo, entre empresas de setores diferentes, no entanto, ela é muito inferior à existência de diferenças no EBITDA, ao longo do tempo, entre empresas do mesmo setor. O resultado coloca em questão a unânime capacidade comparativa do EBITDA. / This research explored the existing controversy between the business community and the academia regarding to the use of the EBITDA. Some academic authors suggest that this indicator has small utility except to compare firms within the same segment; on the other hand, the business environment, strongly use the indicator for many purposes. This difference of opinions has aroused the interest in understanding the reasons of the both sides, and in a greater depth, look at the usefulness of EBITDA to compare companies in the same sector and in different sectors. Much has been written about the usefulness of this indicator in the comparison between companies, however, had not yet seen, nor been observed statistically, the numbers actually behave. This study set out to study the issue in light of statistics. The methodology used in this study was HLM, Hierarchical Linear Modeling. This method, compared to classical regression methods is an elevation, since it is able to decompose the variance of each factor. The main objective of this study was, therefore, to observe the behavior of EBITDAs of firms within the same sector and different sectors, over time. The responses obtained could indicate whether the indicator indeed may be useful (or not) for comparison of similar firms that operate in the same sector and how difference between sectors was perceived. The results showed that there is significant variability in EBITDA between firms within the same sector. Not so for the variability among different sectors, ie, there are differences in EBITDA, over time, between companies of different sectors, however, it is much less than the existence of differences in EBITDA, over time, between firms in the same sector. The result puts in question the unanimous comparative utility of EBITDA.

No description available.

This thesis addresses numerous key points on the application of the margin of appreciation principle in relation to Article 9 (2) of the European Convention on the Protection of Human Rights and Fundamental Freedoms ('Convention').1 In general terms, the margin of appreciation doctrine means that the State is allowed a certain measure of discretion, subject to European supervision, when it takes legislative, administrative, or judicial action in the area of a Convention right.2 The margin of appreciation is given to Contracting States to allow variation amongst them in terms of interpretation of the rights guaranteed.

This thesis addresses numerous key points on the application of the margin of appreciation principle in relation to Article 9 (2) of the European Convention on the Protection of Human Rights and Fundamental Freedoms ('Convention').1 In general terms, the margin of appreciation doctrine means that the State is allowed a certain measure of discretion, subject to European supervision, when it takes legislative, administrative, or judicial action in the area of a Convention right.2 The margin of appreciation is given to Contracting States to allow variation amongst them in terms of interpretation of the rights guaranteed.

No description available.

In the past decade, aggressive scaling of transistor feature size has been a primary force driving higher Static Random Access Memory (SRAM) integration density. Due to the scaling, nanometer SRAM designs are getting more and more stability issues. The traditional way of analyzing stability is the Static Noise Margins (SNM). However, SNM has limited capability to capture critical nonlinearity, so it becomes incapable of characterizing the key dynamics of SRAM operations with induced soft-error. This thesis defines new stability margin metrics using a system-theoretic approach. Nonlinear system theories will be applied rigorously in this work to construct new stability concepts. Based on the phase portrait analysis, soft-error can be explained using bifurcation theory. The state flipping requires a minimum noise current (Icritical) and time (Tcritical). This work derives Icritical analytically for simple L1 model and provides design insight using a level one circuit model, and also provides numerical algorithms on both Icritical and Tcritial for higher a level device model. This stability analysis provides more physical characterization of SRAM noise tolerance property; thus has potential to provide needed yield estimation.

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The construction industry is one of the largest industries in the United States and has major influence on the nation's economy. While there is information about industry-wide labor productivity, there has been very little specifically aimed at analyzing the key macroeconomic factors such as labor productivity and gross margin of the construction industry as a whole and at fourteen of its sub-sectors. To address these shortcomings, the objectives of this research are threefold: (1) quantify the macroeconomic performance of the industry as a whole and at fourteen of its sub-sectors in terms of labor productivity, gross margin, and labor wages, (2) investigate the relationship among the three key parameters over the study period from 1992 to 2007, and (3) develop a quantifying model that predicts the level of a firms' profit as a function of such parameters. In addition, the paper seeks to further examine the interdependence between gross margin and labor productivity and wages by looking at the construction industry as a whole. First, data were collected from the 1997, 2002, and 2007 U.S. Economic Census reports generated by the U.S. Census Bureau. This raw data had discrepancies because of some missing values in data fields. This problem was then resolved by performing a bi-variate linear regression. Second, a one-way ANOVA and a general linear regression analysis was performed to investigate whether there was a statistically significant relationship among gross margin, labor productivity, and labor wages per construction worker. Third, a quantifying model was developed to predict the value of gross margin as a function of key parameters. Lastly, the proposed model was then validated with actual values of gross margin observed in three states, California, Florida, and Texas. The results of this research clearly indicate that there was no statistically significant relationship between labor productivity and labor wages per construction worker. In addition, it was seen that there was no significant relationship between labor wages and gross margin per construction worker. However, this study proved that there was a statistically significant relationship between labor productivity and gross margin per construction worker, which suggests the importance of labor productivity. The validation study proved the reliability of the proposed model in predicting the value of gross margin, with little deviation. This study concludes that sub-sectors experiencing higher labor productivity resulted in more profits as represented by the level of gross margin. This finding conveys the important fact that as labor productivity improves, firm's profits also increase significantly. It is noticeable to find that the construction industry as a whole had experienced a steady increase in its labor productivity and gross margin over the study period.

Esta pesquisa explorou a controvérsia existente entre o meio empresarial e o meio acadêmico no tocante à utilização do EBITDA. Alguns autores acadêmicos apontam que este indicador tem pouca utilidade a não ser para comparar empresas de um mesmo segmento; por outro lado, o meio empresarial, utiliza fortemente o indicador para vários propósitos. Esta diferença de opiniões despertou o interesse em entender as razões dos dois lados e, em um aprofundamento maior, observar a utilidade do EBITDA em comparar empresas de um mesmo setor e em setores diferentes. Muito se escreveu sobre a utilidade que o indicador possui na comparação entre empresas, entretanto, ainda não se havia verificado, e tampouco se observado estatisticamente, como os números se comportam de fato. Este trabalho se propôs a estudar a questão sob prisma estatístico. A metodologia utilizada por esta pesquisa, HLM, Hierarchical Linear Modeling. Este método, se comparado aos métodos de regressão clássica é uma elevação, uma vez que é capaz de decompor as variâncias de cada fator. O objetivo maior deste trabalho seria, portanto, observar os comportamentos dos EBITDAs de empresas de um mesmo setor e setores diferentes, ao longo do tempo. As respostas que seriam obtidas poderiam indicar se de fato o indicador pode ser útil (ou não) para a comparação de empresas similares que atuem em um mesmo setor e como o a diferença entre setores era percebida. Os resultados desta pesquisa mostraram que há uma variabilidade significativa do EBITDA entre firmas de um mesmo setor. O mesmo não aconteceu para a variabilidade entre os setores diferentes, ou seja, há diferenças no EBITDA, ao longo do tempo, entre empresas de setores diferentes, no entanto, ela é muito inferior à existência de diferenças no EBITDA, ao longo do tempo, entre empresas do mesmo setor. O resultado coloca em questão a unânime capacidade comparativa do EBITDA. / This research explored the existing controversy between the business community and the academia regarding to the use of the EBITDA. Some academic authors suggest that this indicator has small utility except to compare firms within the same segment; on the other hand, the business environment, strongly use the indicator for many purposes. This difference of opinions has aroused the interest in understanding the reasons of the both sides, and in a greater depth, look at the usefulness of EBITDA to compare companies in the same sector and in different sectors. Much has been written about the usefulness of this indicator in the comparison between companies, however, had not yet seen, nor been observed statistically, the numbers actually behave. This study set out to study the issue in light of statistics. The methodology used in this study was HLM, Hierarchical Linear Modeling. This method, compared to classical regression methods is an elevation, since it is able to decompose the variance of each factor. The main objective of this study was, therefore, to observe the behavior of EBITDAs of firms within the same sector and different sectors, over time. The responses obtained could indicate whether the indicator indeed may be useful (or not) for comparison of similar firms that operate in the same sector and how difference between sectors was perceived. The results showed that there is significant variability in EBITDA between firms within the same sector. Not so for the variability among different sectors, ie, there are differences in EBITDA, over time, between companies of different sectors, however, it is much less than the existence of differences in EBITDA, over time, between firms in the same sector. The result puts in question the unanimous comparative utility of EBITDA.