20 resultados para Critical Initial Approximations

em Universidade do Minho


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The objective of this paper is to propose a simplified analytical approach to predict the flexural behavior of simply supported reinforced-concrete (RC) beams flexurally strengthened with prestressed carbon fiber reinforced polymer (CFRP) reinforcements using either externally bonded reinforcing (EBR) or near surface mounted (NSM) techniques. This design methodology also considers the ultimate flexural capacity of NSM CFRP strengthened beams when concrete cover delamination is the governing failure mode. A moment–curvature (M–χ) relationship formed by three linear branches corresponding to the precracking, postcracking, and postyielding stages is established by considering the four critical M–χ points that characterize the flexural behavior of CFRP strengthened beams. Two additional M–χ points, namely, concrete decompression and steel decompression, are also defined to assess the initial effects of the prestress force applied by the FRP reinforcement. The mid-span deflection of the beams is predicted based on the curvature approach, assuming a linear curvature variation between the critical points along the beam length. The good predictive performance of the analytical model is appraised by simulating the force–deflection response registered in experimental programs composed of RC beams strengthened with prestressed NSM CFRP reinforcements.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The bond behavior between Fiber Reinforced Polymers (FRPs) and masonry substrates has been the subject of many studies during the last years. Recent accelerated aging tests have shown that bond degradation and FRP delamination are likely to occur in FRP-strengthened masonry components under hygrothermal conditions. While an investigation on the possible methods to improve the durability of these systems is necessary, the applicability of different bond repair methods should also be studied. This paper aims at investigating the debonding mechanisms after repairing delaminated FRP-strengthened masonry components. FRP-strengthened brick specimens, after being delaminated, are repaired with two different adhesives: a conventional epoxy resin and a highly flexible polymer. The latter is used as an innovative adhesive in structural applications. The bond behavior in the repaired specimens is investigated by performing single-lap shear bond tests. Digital image correlation (DIC) is used for deeper investigation of the surface deformation and strains development. The effectiveness of the repair methods is discussed and compared with the strengthened specimens.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Childhood protection is a subject with high value for the society, but, the Child Abuse cases are difficult to identify. The process from suspicious to accusation is very difficult to achieve. It must configure very strong evidences. Typically, Health Care services deal with these cases from the beginning where there are evidences based on the diagnosis, but they aren’t enough to promote the accusation. Besides that, this subject it’s highly sensitive because there are legal aspects to deal with such as: the patient privacy, paternity issues, medical confidentiality, among others. We propose a Child Abuses critical knowledge monitor system model that addresses this problem. This decision support system is implemented with a multiple scientific domains: to capture of tokens from clinical documents from multiple sources; a topic model approach to identify the topics of the documents; knowledge management through the use of ontologies to support the critical knowledge sensibility concepts and relations such as: symptoms, behaviors, among other evidences in order to match with the topics inferred from the clinical documents and then alert and log when clinical evidences are present. Based on these alerts clinical personnel could analyze the situation and take the appropriate procedures.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A new very high-order finite volume method to solve problems with harmonic and biharmonic operators for one- dimensional geometries is proposed. The main ingredient is polynomial reconstruction based on local interpolations of mean values providing accurate approximations of the solution up to the sixth-order accuracy. First developed with the harmonic operator, an extension for the biharmonic operator is obtained, which allows designing a very high-order finite volume scheme where the solution is obtained by solving a matrix-free problem. An application in elasticity coupling the two operators is presented. We consider a beam subject to a combination of tensile and bending loads, where the main goal is the stress critical point determination for an intramedullary nail.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

For any vacuum initial data set, we define a local, non-negative scalar quantity which vanishes at every point of the data hypersurface if and only if the data are Kerr initial data. Our scalar quantity only depends on the quantities used to construct the vacuum initial data set which are the Riemannian metric defined on the initial data hypersurface and a symmetric tensor which plays the role of the second fundamental form of the embedded initial data hypersurface. The dependency is algorithmic in the sense that given the initial data one can compute the scalar quantity by algebraic and differential manipulations, being thus suitable for an implementation in a numerical code. The scalar could also be useful in studies of the non-linear stability of the Kerr solution because it serves to measure the deviation of a vacuum initial data set from the Kerr initial data in a local and algorithmic way.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Félix, Halperin, and Lemaire have shown that the rational module category Mcat and the rational Toomer invariant coincide for simply connected Poincaré duality complexes. We establish an analogue of this result for the sectional category of a fibration.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Dissertação de mestrado em Engenharia de Sistemas

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Over the past four decades the EU cohesion policy’s focus, objectives and content have experienced significant changes as a result of successive reforms aiming at adapting it to a Union in constant evolution. In the early stages, cohesion policy had eminently redistributive goals and it assumed an explicit spatial dimension. In the late nineties, the possibility of an extension towards Eastern European countries and the limited willingness of net contributors to increase funding led to a turning point in cohesion policy. The increased importance of economic growth and job creation in the 2000’s, within the cohesion policy’s context, has led to a misrepresentation of its essence and motivations. Cohesion was losing importance towards competitiveness and regional equity towards national efficiency. Today, cohesion policy is for many EU countries the main mean for mobilising investment in a context of budgetary constraints and credit rationing. In light of the available evidence, it is likely that the overall design and priorities of the current cohesion policy have a limited impact in terms of convergence in many EU regions, especially in the less developed regions. This paper’s main objectives are to analyse the evolution of European cohesion policy throughout its history, to present a picture of cohesion policy in the 2014-2020 programming period and to discuss the main problems associated with its design, priorities and programming model.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We perform Monte-Carlo simulations of the three-dimensional Ising model at the critical temperature and zero magnetic field. We simulate the system in a ball with free boundary conditions on the two dimensional spherical boundary. Our results for one and two point functions in this geometry are consistent with the predictions from the conjectured conformal symmetry of the critical Ising model.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE The aim of this study was to compare the performance of the current conventional Pap smear with liquid-based cytology (LBC) preparations. STUDY DESIGN Women routinely undergoing their cytopathological and histopathological examinations at Fundação Oncocentro de São Paulo (FOSP) were recruited for LBC. Conventional smears were analyzed from women from other areas of the State of São Paulo with similar sociodemographic characteristics. RESULTS A total of 218,594 cases were analyzed, consisting of 206,999 conventional smears and 11,595 LBC. Among the conventional smears, 3.0% were of unsatisfactory preparation; conversely, unsatisfactory LBC preparations accounted for 0.3%. The ASC-H (atypical squamous cells - cannot exclude high-grade squamous intraepithelial lesion) frequency did not demonstrate any differences between the two methods. In contrast, the incidence of ASC-US (atypical squamous cells of undetermined significance) was almost twice as frequent between LBC and conventional smears, at 2.9 versus 1.6%, respectively. An equal percentage of high-grade squamous intraepithelial lesions were observed for the two methods, but not for low-grade squamous intraepithelial lesions, which were more significantly observed in LBC preparations than in conventional smears (2.2 vs. 0.7%). The index of positivity was importantly enhanced from 3.0% (conventional smears) to 5.7% (LBC). CONCLUSIONS LBC performed better than conventional smears, and we are truly confident that LBC can improve public health strategies aimed at reducing cervical lesions through prevention programs.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tese de Doutoramento em Estudos da Criança (Especialidade em Educação Musical)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

"Series title: Springerbriefs in applied sciences and technology, ISSN 2191-530X"

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The links between gender, sex and sexuality and their relevance are theoretically and politically problematic (Richardson, 2007). One of the difficulties in understanding their interconnections is that these terms are often used differently and ambiguously by different authors (and even by the same authors). This article reports the results of an analysis of the articles published in open access communication journals with known impact factor, edited in Portugal and published between 2005 and 2012. The diverse conceptualisations of those three basic concepts and of their (inter)relationships within communication research are identified. The complexity and the intricate (and often implicit) nature of both the meanings of these categories and their relationships underlie and justify our attention and further research. What the findings suggest about the current communication research into gender issues published in the two journals surveyed is that the ‘Gender differences discourse’ (Sunderland, 2004) is the most pervasive discourse (also) in academic practice. Additionally, they show that gender and sex are mainly taken for a fact, not a question that is worth being studied. The editors of these journals, as well as the scholars submitting manuscripts, need to be more aware of the traditional nature of the theoretical and methodological choices that they make regarding gender- and sex-related issues, as well as of the relative lack of attention to sexuality as a research subject.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The evolution of the construction caused a need to use more effective equipments, capable of meeting the increasingly demanding deadlines for the completion of works. In this context, the safety and efficiency of equipment have become key aspects in order to optimize the execution time of the works, as well as reducing labor costs and loss of materials. With the evolution of construction and construction processes, cranes have come to represent a signal of the construction of buildings, revealing to be, in most of the cases, the main equipment of construction sites. Currently, some engineers revels some apprehension regarding the use and handling of cranes which is natural and acceptable, since an equipment failure can lead to serious or fatal accidents. The factors affecting safety management of the cranes in construction sites were investigated, identified, classified and evaluated according to their degree of importance, through interviews with representatives of the general contractors of a set of selected construction sites.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The analysis of journalistic discourse and its social embeddedness has known significant advances in the last two decades, especially due to the emergence and development of Critical Discourse Analysis. However, three important aspects remain under-researched: the time plane in discourse analysis, the discursive strategies of social actors, and the extra- and supra-textual effects of mediated discourse. Firstly, understanding the biography of public matters requires a longitudinal examination of mediated texts and their social contexts but most forms of analysis of journalistic discourse do not account for the time sequence of texts and its implications. Secondly, as the media representation of social issues is, to a large extent, a function of the discursive construction of events, problems and positions by social actors, the discursive strategies that they employ in a variety of arenas and channels ‘‘before’’ and ‘‘after’’ journalistic texts need to be examined. Thirdly, the fact that many of the modes of operation of discourse are extra- or supra-textual calls for a consideration of various social processes ‘‘outside’’ the text. This paper aims to produce a theoretical and methodological contribution to the integration of these issues in discourse analysis by proposing a framework that combines a textual dimension with a contextual one