This classic textbook is a comprehensive introduction to structural steelwork design. It describes the design theory and code requirements for common structures, connections, elements and frames. The book is structured to meet the needs of courses in structural steelwork, introducing and explaining each concept before allowing the student to test the knowledge with practical examples. Each section is illustrated with exercises for the student to reinforce their learning. It continues to be an indispensable introduction to structural steelwork design for students of structural and civil engineering.

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This study’s purpose is testing the rentier state theory’s relationship to the degree of democracy and political stability in the MENA-region. In order to fulfill the aim of this study three research questions are formulated: what kind of relationship exists between oil export per capita and political stability in the MENA region? To what extent does the rentier state theory explain the variation in the degree of democracy in the MENA region? What kind of relationship exists between the rentier state theory and the degree of democracy in the MENA region? To which four hypotheses are formulated. Furthermore, to test these hypotheses and thereby meet the purpose of this study, its methodological approach consists of two regression models: one multiple regression analysis and one bivariate regression analysis. The former is set out to test the relationship between the dependent variable degree of democracy and the independent variables oil rent, tax revenue and political stability, using the control variable HDI. The latter regression analysis is employed to test the relationship between oil export per capita as the independent variable and political stability as the dependent variable. The multiple regression model finds insufficient support for the rentier state theory as an explanatory model for the variation in democracy in the MENA region, only observing a significant relationship with tax revenue. Whereas the bivariate regression model finds a significant positive relationship between oil export per capita and political stability. These findings do not exclude the possibility that the rentier state theory can explain variations in the degree of democracy in other oil rich regions outside of the Middle East and North Africa region. Nor do the results exclude the possibility of the rentier state theory explaining the variations in degree of democracy in certain MENA region countries. Additionally, there is reason to believe that a higher oil export per capita contributes to a higher degree of political stability in the MENA region. The observations of this study are problematized using earlier research that propose further studies including explanatory factors beyond the rentier state theory in the MENA region. These factors include armed conflicts, post colonialism and religious radicalization.

With the aim of contributing to the theoretical discussion of small state behaviour, this thesis investigates the Nordic state’s security strategies concerning the Arctic region. The applied theoretical framework is based upon a traditional state-centric understanding of security to investigate if the predicted behaviour derived from small state theory can be captured in the Nordic states' security strategies in the Arctic region. The study is conducted by a qualitative content analysis utilising Jacob Westberg’s theorisation of security strategies through the categories of context, ends, means and ways. The state-centric security focus is steered by the traditional realist focus of small states and motivated by the deteriorating geopolitical sphere currently occurring in the Arctic region, where the small Nordic states operate next to great powers. The results demonstrate that several aspects can be argued to coincide with the assumptions derived from small state theory, albeit some do not fully conform. Most apparent are the aspects relating to the importance of alliances and cooperation. Differences are also deductible between the small state's strategies, primarily between Denmark and Norway vis-a-vis Finland and Sweden. This incoherency enables a discussion of the relevance of states' size in the case of the Arctic theatre and of the noticeable shift in the states' referent security object. The analytical framework captures issues that point towards a more state-centric security understanding, presenting new threats to the state's survival in the Arctic region.

No / The fourth edition of Structural Steelwork: Design to Limit State Theory describes the design theory and code requirements for common structures, connections, elements, and frames. It provides a comprehensive introduction to structural steelwork design with detailed explanations of the principles underlying steel design.

Many chemical reactions can be described as the crossing of an energetic barrier. This process is mediated by an invariant object in phase space. One can construct a normally hyperbolic invariant manifold (NHIM) of the reactive dynamical system which is an invariant sphere that can be considered as the geometric representation of the transition state itself. The NHIM has invariant cylinders (reaction channels) attached to it. This invariant geometric structure survives as long as the invariant sphere is normally hyperbolic. We applied this theory to the hydrogen exchange reaction in three degrees of freedom in order to figure out the reason of the transition state theory (TST) failure. Energies high above the reaction threshold, the dynamics within the transition state becomes partially chaotic. We have found that the invariant sphere first ceases to be normally hyperbolic at fairly low energies. Surprisingly normal hyperbolicity is then restored and the invariant sphere remains normally hyperbolic even at very high energies. This observation shows two different energy values for the breakdown of the TST and the breakdown of the NHIM. This leads to seek another phase space object that is related to the breakdown of the TST. Using theory of the dividing surface including reactive islands (RIs), we can investigate such an object. We found out that the first nonreactive trajectory has been found at the same energy values for both collinear and full systems, and coincides with the first bifurcation of periodic orbit dividing surface (PODS) at the collinear configuration. The bifurcation creates the unstable periodic orbit (UPO). Indeed, the new PODS (UPO) is the reason for the TST failure. The manifolds (stable and centre-stable) of the UPO clarify these expectations by intersecting the dividing surface at the boundary of the reactive island (on the collinear and the three (full) systems, respectively).

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-04-24T14:13:26Z No. of bitstreams: 1 2012 - Ana Carolina Bello de Souza.pdf: 1911170 bytes, checksum: 62c70571aeb2100b8313dc1ef44eac2b (MD5) / Made available in DSpace on 2017-04-24T14:13:26Z (GMT). No. of bitstreams: 1 2012 - Ana Carolina Bello de Souza.pdf: 1911170 bytes, checksum: 62c70571aeb2100b8313dc1ef44eac2b (MD5) Previous issue date: 2012-10-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / In this work, the theoretical study of the gas-phase bimolecular nucleophilic substitution reaction, CH3Cl + OH- CH3OH + Cl-, is introduced, aiming the description of the potential energy surface, the calculation of rate constants and the investigation of the effect of increasing the side chain (changing the CH3 radical in the reaction cited above by the radicals ethyl, n-propyl, i-propyl, n-butyl, s-butyl e t-butyl). The theoretical calculations have been first performed at the MP2/6-31+G(d) level for the geometry optimizations and vibrational frequencies calculations. Single point calculations at the CCSD(T)/6-31+G(d) level have also been performed in order to improve the total energies for the stationary points. However, the relative energies of these stationary points at both MP2 and CCSD(T) level shown close results, so that the single point calculations at the CCSD(T) level have not been proved strictly necessary and have therefore not been performed for all the points along the potential energy surface. The minimum energy path has been described by the intrinsic reaction coordinate method, calculated at the MP2/6-31+G(d) by performing sequential geometry optimizations starting from the saddle point. The calculated enthalpy difference at 298K for the reaction has been determined as -49.5 kcal/mol, in good agreement with the literature value: -50.5 kcal/mol. The calculated rate constant has been obtained as 1.41 x 10-9 cm3.molecule-1.s-1, at 298,15K, in excellent agreement with the experimental data: 1.3 ? 1.6 x 10-9 cm3.molecule-1.s-1.Moreover, the rate constants show non-Arrhenius behavior, decreasing as the temperature increases, which is consistent with the experimental expectation. In this way, the performance of the variational transition state theory for this reaction can be considered satisfactory. By increasing the side chain of the reactant, other reaction channels have been observed: the bimolecular elimination E2 channel and the attack of the nucleophile from the same plane of the exit group (the front-SN2).For these reactions of the alkyl chlorides on n carbon atoms (1 < n ? 4), the B3LYP/6-31+G(d,p) level has been adopted for geometry optimizations and vibrational frequencies. Then, single point calculations at the CCSD(T)/6-31+G(d,p)//B3LYP/6- 31+G(d,p) level have been performed. A comparison of the reaction channels, back- SN2 and E2, shows that the E2 channel is kinetically favored, whereas the SN2 products are thermodynamically more stable. As expected, high values for the potential height have been observed for the front-SN2, being these channels disfavored in all cases. In general, the energy of the saddle points in respect to the isolated reactants slightly depend upon the size of the side chain. / Este trabalho trata do estudo te?rico das rea??es de substitui??o nucleof?lica de segunda ordem, CH3Cl + OH- CH3OH + Cl-, em fase gasosa, visando estudar a superf?cie de energia potencial, obter as constantes de velocidade e ainda verificando o efeito do aumento da cadeia lateral (trocando o radical CH3 na rea??o descrita acima por radicais etil, n-propil, i-propil, n-butil, s-butil e t-butil). Primeiramente, c?lculos te?ricos para otimiza??es de geometria e frequ?ncia foram realizados em n?vel MP2/6-31+G(d) para a rea??o CH3Cl + OH- CH3OH + Cl- e, em seguida, c?lculos single-point em n?vel CCSD(T)/6-31+G(d) foram realizados para corrigir os valores da energia eletr?nica dos pontos estacion?rios obtidos no caminho de rea??o. Entretanto, os valores obtidos para as energias relativas em n?veis MP2 e CCSD(T) foram muito pr?ximos, n?o sendo estritamente necess?rio refinar,atrav?s de c?lculos single-point em n?vel CCSD(T)/6- 31+G(d),os valores de energia de todos os pontos obtidos na superf?cie de energia potencial. O caminho de rea??o menor energia foi descrito pela coordenada de rea??o intr?nseca, calculada por otimiza??es de geometrias de uma sequ?ncia de configura??es ao redor do ponto de sela em n?vel MP2/6-31+G(d). A diferen?a de entalpia a 298K calculada para a rea??o foi de -49,5 kcal/mol, em bom acordo com o dado da literatura, -50,5 kcal/mol. A constante de velocidade da rea??o obtida foi de 1,41 x 10-9 cm3.mol?cula-1.s-1, a 298,15K, em excelente acordo com o dado experimental: 1,3 ? 1,6 x 10-9 cm3.mol?cula-1.s-1. Al?m disso, as constantes de velocidade globais apresentam comportamento n?o-Arrhenius, diminuindo conforme a temperatura aumenta, em um perfil consistente com a observa??o experimental. Dessa forma, a aplica??o da teoria de estado de transi??o se mostra satisfat?ria para essa rea??o. A partir do aumento da cadeia lateral, outros canais de rea??o foram observados, em prov?vel competi??o ? substitui??o nucleof?lica de ordem 2: a elimina??o de segunda ordem, E2. O ataque do nucle?filo pela frente da cadeia tamb?m foi obtido e investigado. Para as rea??es dos cloretos de alquila com cadeia lateral de n carbonos (1 < n ? 4), o n?vel B3LYP/6- 31+G(d,p) foi adotado para c?lculos de otimiza??es e frequ?ncias. Posteriormente, c?lculos em n?vel CCSD(T)/6-31+G(d,p)//B3LYP/6-31+G(d,p) foram realizados. Comparando os canais de rea??o de substitui??o nucleof?lica back e de elimina??o, o canal cineticamente favorecido foi o de elimina??o, por?m os produtos termodinamicamente mais est?veis s?o os de substitui??o nucleof?lica. Como esperado, observa-se uma barreira de potencial muito alta para as rea??es substitui??o pela frente, sendo esses canais desfavorecidos em todos os casos.Em geral, a diferen?a de energia dos pontos de sela em rela??o aos reagentes isolados mostra pequena depend?ncia com o aumento da cadeia lateral linear

La thèse, composée de deux grands ensembles, explicite d’abord la trajectoire de la notion de « gouvernementalité » dans les cours de Michel Foucault au Collège de France de 1976 et 1984 afin d’établir un nouveau cadre théorique d’analyse du conflit politique à partir de l’étude des rapports de réciprocité entre les pratiques étatiques et les contre-conduites. Dans un deuxième temps, elle met ce cadre théorique à l’épreuve d’ensembles empiriques afin de tracer une généalogie de l’État au XXème et XXIème siècles à partir d’une ethnologie du dire-vrai dans la pratique sociale. Sur des aires, des temps et des populations variables, elle identifie quatre régimes différents de véridiction/juridiction des pratiques gouvernementales logiquement articulés les uns aux autres par des rapports de réciprocité successifs :1 / le régime libéral social de la res socialis en France des années 1890 aux années 1960 ; 2/ le régime de la res nullius dans les comités d’action en France dans les années 68 ; 3/ le régime néolibéral de la res economica à l’échelle mondiale depuis les années 1970 ; 4/ le régime de la res communis dans la Coordinadora del agua et les comités de l’eau boliviens dans les années 2000. Chacun de ces régimes implique une expérience différente de l’État en termes de degré et d’espaces de gouvernementalité, d’effets des politiques étatiques sur le niveau des inégalités et la structuration des rapports entre classes sociales ou sur le degré de démocratisation de la vie publique. C’est donc à une évaluation historiquement différenciée de l’État qu’invite la méthode foucaldienne d’analyse des formes de véridiction sur lesquelles sont indexées les pratiques gouvernementales. / The thesis is made of two parts and analyzes at first the trajectory of the notion of “governmentality” in Michel Foucault’s courses at the Collège de France between 1976 and 1984 to develop a new analytical framework of political conflict through the reciprocal relationships between state practices and counter-conducts. Secondly, it puts this theoretical framework to the test of a series of empirical data to draw a genealogy of the State in the twentieth and twenty-first centuries from the viewpoint of an ethnology of truth telling within social practices. On variable areas, times and populations, it identifies four different regimes of veridiction/jurisdiction for governmental practices logically articulated some in the others by successive and reciprocal relationships: 1/ the social liberal regime of the res socialis in France from the 1890 to 1960s; 2/ the regime of the res nullius for the action committees in France in the 1968s ; 3/ the neoliberal regime of the res economica at the global scale since the 1970s; 4/ the regime of the res communis for the Coordinadora del agua and bolivian water committees in the 2000s. Each of these regimes involves a different experiment of the State in terms of degree and spaces of governmentality, of effects of state policies on the level of social inequalities between classes or on the degree of democratization of public life. It is thus to a historically differentiated evaluation of the State that invites the foucaultian method of analyzing the veridictions to which are indexed the governmental practices.

Although utilization of polarimetry techniques for recognition of military and civilian targets is well established in the narrowband context, it is not yet fully established in a broadband sense as compared to planetary area of research. The concept of combining polarimetry together with certain areas of broadband technology and thus forming a robust signature and feature set has been the main theme of this thesis. This is important, as basing the feature set on multiple types of signatures can increase the accuracy of the recognition process. In this thesis, the concept of radar target recognition based upon a polarization signature in a broadband context is examined. A proper UWB radar signal can excite the target dominant resonances and, consequently, reveal information about the target principle dimensions; while diversity in the polarization domain revealed information about the target shape. The target dimensions are used to classify the target, and then information about its shape is used to identify it. Fused together and inferred from the target characteristic polarization states, it was verified that the polarization information at dominant resonant frequencies have both a physical interpretation and attributes (as seen in section ‎3.4.3) related to the target symmetry, linearity, and orientation. In addition, this type of information has the ability to detect the presence of major scattering mechanisms such as strong specular reflection as in the case of the cylinder flat ends. Throughout the thesis, simulated canonical targets with similar resonant frequencies were used, and thus identification of radar targets was based solely on polarization information. In this framework, the resonant frequencies were merely identified as peaks in the frequency response for simple or low damping targets such as thin metal wires, or alternatively identified as the imaginary parts of the complex poles for complex or high damping targets with significant diameter and dielectric properties. Therefore, the main contribution of this thesis originates from the ability to integrate the optimum polarization states in a broadband context for improved target recognition performance. In this context, the spectral dispersion originating from the broad nature of the radar signal, the lack of accuracy in extracting the target resonances, the robustness of the polarization feature set, the representation of these states in time domain, and the feature set modelling with spatial variation are among the important issues addressed with several approaches presented to overcome them. The general approach considered involved a subset of “representative” times in the time domain, or correspondingly, “representative frequencies” in the frequency domain with which to associate optimum polarization states with each member of the subset are used. The first approach in chapter ‎3 involved the polarization representation by a set of frequency bands associated with the target resonant frequencies. This type of polarization description involved the formulation of a wideband scattering matrix to accommodate the broad nature of the signal presentation with appropriate bandwidth selection for each resonance; good estimation of the optimum polarization states in this procedure was achievable even for low signal-to-noise ratios. The second approach in chapter ‎4 extended the work of chapter ‎3 and involved the modification of the optimum polarization states by their associated powers. In addition, this approach included an identification algorithm based on the nearest neighbour technique. To identify the target, the identification algorithm involved the states at a set of resonant frequencies to give a majority vote. Then, a comparison of the performance of the modified polarization states and the original states demonstrated good improvement when the modified set is used. Generally, the accuracy of the resonance set estimate is more reliable in the time domain than the frequency domain, especially for resonances well localized in time. Therefore, the third approach in chapter ‎5 deals with the optimum states in the time domain where the extension to a wide band context was possible by the virtue of the polarization information embodied in the energy of the resonances. This procedure used a model-based signature to model the target impulse response as a set of resonances. The relevant resonance parameters, in this case, the resonant frequency and its associated energy, were extracted using the Matrix Pencil of Function algorithm. Again, this approach of sparse representation is necessary to find descriptors from the target impulse response that are time-invariant, and at the same time, can relate robustly to the target physical characteristics. A simple target such as a long wire showed that indeed polarization information contained in the target resonance energies could reflect the target physical attributes. In addition, for noise-corrupted signals and without any pulse averaging, the accuracy in estimating the optimum states was sufficiently good for signal to noise ratios above 20dB. Below this level, extraction of some members of the resonance set are not possible. In addition, using more complex wire models of aircraft, these time-based optimum states could distinguish between similar dimensional targets with small structural differences, e.g. different wing dihedral angles. The results also showed that the dominant resonance set has members belonging to different structural sections of the target. Therefore, incorporation of a time-based polarization set can give the full target physical characteristics. In the final procedure, a statistical Kernel function estimated the feature set derived previously in chapter ‎3, with aspect angle. After sampling the feature set over a wide set of angular aspects, a criterion based on the Bayesian error bisected the target global aspect into smaller sectors to decrease the variance of the estimate and, subsequently, decrease the probability of error. In doing so, discriminative features that have acceptable minimum probability of error were achievable. The minimum probability of error criterion and the angular bisection of the target could separate the feature set of two targets with similar resonances.

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