885 resultados para post-structural theory


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Neste artigo, pretende-se desenvolver uma versão desagregada da abordagem pós-Keynesiana para o crescimento econômico, mostrando que de fato esse modelo pode ser tratado como um caso particular do modelo Pasinettiano de mudança estrutural e crescimento econômico. Utilizando-se o conceito de integração vertical, torna-se possível conduzir a análise iniciada por Kaldor (1956) e Robinson (1956, 1962), e seguido por Dutt (1984), Rowthorn (1982) e, posteriormente, Bhaduri e Marglin (1990) em um modelo multi-sectorial em que há aumentos da demanda e produtividade em ritmos diferentes em cada setor. Ao adotar essa abordagem, é possível mostrar que a dinâmica de mudança estrutural está condicionada não apenas aos padrões de demanda de evolução das preferências e da difusão do progresso tecnológico, mas também com as características distributivas da economia, que podem dar origem a diferentes regimes setoriais de crescimento econômico. Além disso, é possível determinar a taxa natural de lucro que faz com que a taxa de mark-up seja constante ao longo do tempo. _________________________________________________________________________________ ABSTRACT

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Predicting accurate bond length alternations (BLAs) in long conjugated oligomers has been a significant challenge for electronic-structure methods for many decades, made particularly important by the close relationships between BLA and the rich optoelectronic properties of π-delocalized systems. Here, we test the accuracy of recently developed, and increasingly popular, double hybrid (DH) functionals, positioned at the top of Jacobs Ladder of DFT methods of increasing sophistication, computational cost, and accuracy, due to incorporation of MP2 correlation energy. Our test systems comprise oligomeric series of polyacetylene, polymethineimine, and polysilaacetylene up to six units long. MP2 calculations reveal a pronounced shift in BLAs between the 6-31G(d) basis set used in many studies of BLA to date and the larger cc-pVTZ basis set, but only modest shifts between cc-pVTZ and aug-cc-pVQZ results. We hence perform new reference CCSD(T)/cc-pVTZ calculations for all three series of oligomers against which we assess the performance of several families of DH functionals based on BLYP, PBE, and TPSS, along with lower-rung relatives including global- and range-separated hybrids. Our results show that DH functionals systematically improve the accuracy of BLAs relative to single hybrid functionals. xDH-PBE0 (N4 scaling using SOS-MP2) emerges as a DH functional rivaling the BLA accuracy of SCS-MP2 (N5 scaling), which was found to offer the best compromise between computational cost and accuracy the last time the BLA accuracy of DFT- and wave function-based methods was systematically investigated. Interestingly, xDH-PBE0 (XYG3), which differs to other DHs in that its MP2 term uses PBE0 (B3LYP) orbitals that are not self-consistent with the DH functional, is an outlier of trends of decreasing average BLA errors with increasing fractions of MP2 correlation and HF exchange.

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This paper explores how the liberal tradition of political thought has dealt with the prospect of limits to economic growth and how it should approach this issue in the future. Using Andrew Moravcsik’s explanatory liberal theory, it finds that the commitment of governments to growth stems primarily from the aggregation of societal preferences. The arguments of liberal thinkers who have grappled with the issue of growth are then examined to gain a deeper theoretical understanding of the relationship between liberal democracy and growth. These include John Stuart Mill, for whom a non-growing economy was essential for overcoming the tension between liberty and equality; Ronald Dworkin who argues that growth is a derivative means to further more fundamental ends; and Marcel Wissenburg who suggests that it is legitimate for liberal democracies to limit the preference for growth if it risks undermining liberal norms and institutions. Using these theoretical insights, it is argued that environmental degradation, which is partly driven by growth, now threatens fundamental liberal commitments to state neutralism, utilitarianism, inalienable individual rights and above all human autonomy. Therefore, liberal democratic states not only can, but must move towards a post-growth economy to secure these objectives into the future.

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The topics of succession and post-disturbance ecosystem recovery have a long and convoluted history. There is extensive redundancy within this body of theory, which has resulted in confusion, and the links among theories have not been adequately drawn. This review aims to distil the unique ideas from the array of theory related to ecosystem change in response to disturbance. This will help to reduce redundancy, and improve communication and understanding between researchers. We first outline the broad range of concepts that have developed over the past century to describe community change in response to disturbance. The body of work spans overlapping succession concepts presented by Clements in 1916, Egler in 1954, and Connell and Slatyer in 1977. Other theories describing community change include state and transition models, biological legacy theory, and the application of functional traits to predict responses to disturbance. Second, we identify areas of overlap of these theories, in addition to highlighting the conceptual and taxonomic limitations of each. In aligning each of these theories with one another, the limited scope and relative inflexibility of some theories becomes apparent, and redundancy becomes explicit. We identify a set of unique concepts to describe the range of mechanisms driving ecosystem responses to disturbance. We present a schematic model of our proposed synthesis which brings together the range of unique mechanisms that were identified in our review. The model describes five main mechanisms of transition away from a post-disturbance community: (i) pulse events with rapid state shifts; (ii) stochastic community drift; (iii) facilitation; (iv) competition; and (v) the influence of the initial composition of a post-disturbance community. In addition, stabilising processes such as biological legacies, inhibition or continuing disturbance may prevent a transition between community types. Integrating these six mechanisms with the functional trait approach is likely to improve the predictive capacity of disturbance theory. Finally, we complement our discussion of theory with a case study which emphasises that many post-disturbance theories apply simultaneously to the same ecosystem. Using the well-studied mountain ash (Eucalyptus regnans) forests of south-eastern Australia, we illustrate phenomena that align with six of the theories described in our model of rationalised disturbance theory. We encourage further work to improve our schematic model, increase coverage of disturbance-related theory, and to show how the model may link to, or integrate with, other domains of ecological theory.

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Graphitic like layered materials exhibit intriguing electronic structures and thus the search for new types of two-dimensional (2D) monolayer materials is of great interest for developing novel nano-devices. By using density functional theory (DFT) method, here we for the first time investigate the structure, stability, electronic and optical properties of monolayer lead iodide (PbI2). The stability of PbI2 monolayer is first confirmed by phonon dispersion calculation. Compared to the calculation using generalized gradient approximation, screened hybrid functional and spin-orbit coupling effects can not only predicts an accurate bandgap (2.63 eV), but also the correct position of valence and conduction band edges. The biaxial strain can tune its bandgap size in a wide range from 1 eV to 3 eV, which can be understood by the strain induced uniformly change of electric field between Pb and I atomic layer. The calculated imaginary part of the dielectric function of 2D graphene/PbI2 van der Waals type hetero-structure shows significant red shift of absorption edge compared to that of a pure monolayer PbI2. Our findings highlight a new interesting 2D material with potential applications in nanoelectronics and optoelectronics.

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Purpose – The purpose of the paper is to use a case study setting involving the implementation of an enterprise resource planning (ERP) system to expose and analyze the conflicts in the characterizations of the post bureaucratic organisation (PBO) in the literature. ERP implementations are often accompanied by increasing levels of stress in organizations that place pressures on organizational relationships and structures. Additionally, ERPs are regarded as introducing their own techno-logic of centralization, standardization and formalization that provides an apparent contrast to the exhortations about employee empowerment.Design/methodology/approach – A case study of ERP implementation in a medium-sized entity is presented. The paper explores aspects of ERP and PBO from the context of postmodern organization theory.Findings – Some concerns about PBO identified in the literature are reflected in the case situation. For example, there is a commitment to give up private time and work flexibly by some employees. The paper also provides evidence of the way the management team substitute their reliance on a key individual knowledge worker for that of an ERP system and external vendor support. Paradoxically, trust in that same knowledge worker and between core users of the system is essential to enable the implementation of the system.

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Socialist gender ideology and practice, this illustrated volume examines the individuals in different contexts; the building types the women produced; the books and theory they were able to write; their contacts to international organizations; and their representation on both sides of the Iron Curtain.

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Contemporary Central American fiction has become a vital project of revision of the tragic events and the social conditions in the recent history of the countries from which they emerge. The literary projects of Sergio Ramirez (Nicaragua), Dante Liano (Guatemala), Horacio Castellanos Moya (El Salvador), and Ramon Fonseca Mora (Panama), are representative of the latest trends in Central American narrative. These trends conform to a new literary paradigm that consists of an amalgam of styles and discourses, which combine the testimonial, the historical, and the political with the mystery and suspense of noir thrillers. Contemporary Central American noir narrative depicts the persistent war against social injustice, violence, criminal activities, as well as the new technological advances and economic challenges of the post-war neo-liberal order that still prevails throughout the region. Drawing on postmodernism theory proposed by Ihab Hassan, Linda Hutcheon and Brian MacHale, I argued that the new Central American literary paradigm exemplified by Sergio Ramirez’s El cielo llora por mí, Dante Liano’s El hombre de Montserrat, Horacio Castellanos Moya’s El arma en el hombre and La diabla en el espejo, and Ramon Fonseca Mora’s El desenterrador, are highly structured novels that display the characteristic marks of postmodern cultural expression through their ambivalence, which results from the coexistence of multiple styles and conflicting ideologies and narrative trends. The novels analyzed in this dissertation make use of a noir sensitivity in which corruption, decay and disillusionment are at their core to portray the events that shaped the modern history of the countries from which they emerge. The revolutionary armed struggle, the state of terror imposed by military regimes and the fight against drug trafficking and organized crime, are among the major themes of these contemporary works of fiction, which I have categorized as perfect examples of the post-revolutionary post-modernism Central American detective fiction at the turn of the 21st century.

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Corrosion of steel tendons is a major problem for post-tensioned concrete, especially because corrosion of the steel strands is often hard to detect inside grouted ducts. Non-metallic tendons can serve as an alternative material to steel for post-tensioning applications. Carbon fiber reinforced polymer (CFRP), given its higher strength and elastic modulus, as well as excellent durability and fatigue strength, is the most practical option for post-tensioning applications. The primary objective of this research project was to assess the feasibility of the use of innovative carbon fiber reinforced polymer (CFRP) tendons and to develop guidelines for CFRP in post-tensioned bridge applications, including segmental bridges and pier caps. An experimental investigation and a numerical simulation were conducted to compare the performance of a scaled segmental bridge model, post-tensioned with two types of carbon fiber strands and steel strands. The model was tested at different prestress levels and at different loading configurations. While the study confirms feasibility of both types of carbon fiber strands for segmental bridge applications, and their similar serviceability behavior, strands with higher elastic modulus could improve structural performance and minimize displacements beyond service loads. As the second component of the project, a side-by-side comparison of two types of carbon fiber strands against steel strands was conducted in a scaled pier cap model. Two different strand arrangements were used for post-tensioning, with eight and six strands, respectively representing an over-design and a slight under-design relative to the factored demand. The model was tested under service and factored loads. The investigation confirmed the feasibility of using carbon fiber strands in unbonded post-tensioning of pier caps. Considering both serviceability and overload conditions, the general performance of the pier cap model was deemed acceptable using either type of carbon fiber strands and quite comparable to that of steel strands. In another component of this research, creep stress tests were conducted with carbon fiber composite cable (CFCC). The anchorages for all the specimens were prepared using a commercially available expansive grout. Specimens withstood 95% of the guaranteed capacity provided by the manufacturer for a period of five months, without any sign of rupture.

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This book examines how foreign direct investment (FDI) inflows to Central and Eastern Europe have changed after the Great Recession. It argues that beyond their cyclical effects, the economic crisis and the changing competitiveness of Central and Eastern European countries have had structural impacts on FDI in the region. FDI has traditionally been viewed as the key driver of national development, but the apparent structural shift means that focusing on cheap labour as a competitive advantage is no longer a viable strategy for the countries in the region. The authors argue that these countries need to move beyond the narrative of upgrading (attracting FDI inflows with increasingly higher value added), and focus on ensuring greater value capture instead. A potential way for doing this is by developing the conditions in which innovative national companies can emerge, thrive and eventually develop into lead firms of global value chains. The book provides readers with a highly informative account of the reasons why this shift is necessary, as well as diverse perspectives and extensive discussions on the dynamics and structural impacts of FDI in post-crisis Central and Eastern Europe.

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The cemeterial units, are places of social practices of everyday life and worship and the tomb where nostalgia can be externalized and the memory of the deceased revered. In Western societies we can find a category of artifacts meant to evoke the memory or honor the dead. In this paper we we mention three examples of products that enabled a reflection on the concepts that gave rise to their ways, and that risks to fit them into a new "material culture", in that it may have created a break with the traditional system codes and standards shared by companies, and its manifestations in relation to the physical creation of this category of products. This work offers a reflection on the Design Products.What probably makes it special is the field where it is located: the design of products in one post mortem memory. Usually made of granite rock or marble, have the form of plate or tablet, open book or rolled sheet. On one side have a photograph of the person who intend to honor and inscriptions. The thought of inherent design of this work put on one side the intricate set of emotions that this type of product can generate, and other components more affordable, and concerning the form, function and object interactions with users and with use environments. In the definition of the problem it was regarded as mandatory requirements: differentiation, added value and durability as key objectives.The first two should be manifested in the various components / product attributes. The aesthetic and material/structural durability of product necessarily imply the introduction of qualifying terms and quantitative weights, which positively influence the generation and evaluation of concepts based on the set of 10 principles for the project that originated a matrix as a tool to aid designing products. The concrete definition of a target audience was equally important. At this stage, the collaboration of other experts in the fields of psychology and sociology as disciplines with particular ability to understand individuals and social phenomena respectively was crucial. It was concluded that a product design to honor someone post mortem, should abandon the more traditional habits and customs to focus on identifying new audiences. Although at present it can be considered a niche market, it is believed that in the future may grow as well as their interest in this type of products.

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Within the framework of basic psychological needs theory (Deci & Ryan, 2000), multilevel structural equation modeling (MSEM) with a time-lagged design was used to test a mediation model examining the relationship between perceptions of coaches’ interpersonal styles (autonomy supportive and controlling), athletes’ basic psychological needs (satisfaction and thwarting), and indicators of well-being (subjective vitality) and ill-being (burnout), estimating separately between and within effects. The participants were 597 Spanish male soccer players aged between 11 and 14 years (M = 12.57, SD = 0.54) from 40 teams who completed a questionnaire package at two time points in a competitive season. Results revealed that at the individual level, athletes’ perceptions of autonomy support positively predicted athletes’ need satisfaction (autonomy, competence, and relatedness), whereas athletes’ perceptions of controlling style positively predicted athletes’ need thwarting (autonomy, competence, and relatedness). In turn, all three athletes’ need satisfaction dimensions predicted athletes’ subjective vitality and burnout (positively and negatively, respectively), whereas competence thwarting negatively predicted subjective vitality and competence and relatedness positively predicted burnout. At the team level, team perceptions of autonomy supportive style positively predicted team autonomy and relatedness satisfaction. Mediation effects only appeared at the individual level.

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This thesis is concerned with change point analysis for time series, i.e. with detection of structural breaks in time-ordered, random data. This long-standing research field regained popularity over the last few years and is still undergoing, as statistical analysis in general, a transformation to high-dimensional problems. We focus on the fundamental »change in the mean« problem and provide extensions of the classical non-parametric Darling-Erdős-type cumulative sum (CUSUM) testing and estimation theory within highdimensional Hilbert space settings. In the first part we contribute to (long run) principal component based testing methods for Hilbert space valued time series under a rather broad (abrupt, epidemic, gradual, multiple) change setting and under dependence. For the dependence structure we consider either traditional m-dependence assumptions or more recently developed m-approximability conditions which cover, e.g., MA, AR and ARCH models. We derive Gumbel and Brownian bridge type approximations of the distribution of the test statistic under the null hypothesis of no change and consistency conditions under the alternative. A new formulation of the test statistic using projections on subspaces allows us to simplify the standard proof techniques and to weaken common assumptions on the covariance structure. Furthermore, we propose to adjust the principal components by an implicit estimation of a (possible) change direction. This approach adds flexibility to projection based methods, weakens typical technical conditions and provides better consistency properties under the alternative. In the second part we contribute to estimation methods for common changes in the means of panels of Hilbert space valued time series. We analyze weighted CUSUM estimates within a recently proposed »high-dimensional low sample size (HDLSS)« framework, where the sample size is fixed but the number of panels increases. We derive sharp conditions on »pointwise asymptotic accuracy« or »uniform asymptotic accuracy« of those estimates in terms of the weighting function. Particularly, we prove that a covariance-based correction of Darling-Erdős-type CUSUM estimates is required to guarantee uniform asymptotic accuracy under moderate dependence conditions within panels and that these conditions are fulfilled, e.g., by any MA(1) time series. As a counterexample we show that for AR(1) time series, close to the non-stationary case, the dependence is too strong and uniform asymptotic accuracy cannot be ensured. Finally, we conduct simulations to demonstrate that our results are practically applicable and that our methodological suggestions are advantageous.

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This article shifts from the formal learning spaces of school anduniversity to an Australian public swimming pool to playfullyengage some of the dilemmas that recent theory poses forcurriculum studies. The article enacts multiple diffractions(Barad, 2007) as theory becomes swimming and swimmingbecomes theory, and ideas and movements are themselvesdiffracted or changed by the writing of a poem. What does thepool teach us? What is learnt at the pool? How does learningemerge at the pool? Physics, chemistry, biology, and artistrycombine, as multiple human and non-human bodies intra-act(Barad, 2007), calling each other into being in this exploration ofhow distributed agencies and fractal causalities (Bennett, 2010)change how learning might be thought, represented, andswum. The poem incorporated here serves as provocation andinspiration for other scholars struggling with these educationaldilemmas and interested in arts-based research.