https://docentes.fct.unl.pt/lblm/files/inorgchem-2018-57-8078.pdf

Spectrochimica Acta Part B: Atomic Spectroscopy, 130 (2017) 35-38. doi:10.1016/j.sab.2017.02.006

Abstract Pipelines and piping components may experience large cyclic deformations during a reduced number of cycles (Ni = 1�100 cycles), when subjected to extreme cyclic loading events (e.g. hurricanes, support settlements, earthquakes). In accordance with these loading scenarios, a lateral movement can be applied to the pipeline inducing bending stresses that gradually promotes strain localization, due to progressive plastic instabilities (buckling), damage evolution and final failure. This work aims at characterizing ultra-low cycle fatigue (ULCF) behaviour of the \{X52\} piping steel under bending and local buckling state. An experimental program was carried out to derive \{ULCF\} data for smooth, notched and flat-grooved specimen geometries under cyclic bending. Furthermore, the small-scale tests were simulated in ABAQUS� with the objective of computing the parameters governing the fatigue damage models. The classical Coffin-Manson strain-life relation commonly used in the low cycle fatigue (LCF) regime is proposed to model the fatigue lives. In addition, the Xue model, particularly dependent of the monotonic fracture strain was also used for the prediction of the number of cycles until the crack initiation. The numerical data obtained with these models are compared, being achieved similar fatigue lives predictions for notched plane specimens. For the case of flat-grooved specimens which provides plain strain conditions, an overestimation from the Coffin-Manson relation was observed while the Xue model reproduces very good results for both specimens' series.

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The Urban-Architect role in smart cities is a topic that has not received much attention from the scientific community. This article studies the work of the traditional responsible for thinking the cities, the Urban Architect. Under a critical proposition, aspects of this problematic are identified, which is in part nourished by the deficient action of these professionals.
The study was divided into two parts, the first one materialized through a bibliographical survey, in this section it is presented; 1 - a more detailed description of why this research work; 2 - a contextualisation of the transition of the scenarios is explained; 3 - the problematization and the reflection are raised for some reasons of the "disqualification" of the action of the architect-urbanist in the scene.
The second is based on the discussion between the authors and case studies; 4 - aspects are discussed and some characteristics are listed for "(re) framing" within the ideal scenario; 5 - four case studies are described: two smart cities built from scratch and two cities being transformed into smart cities; 6 - the limitations, conclusions and strands for future work are woven.

Despite increasing calls for evidence-based policies, knowledge about the practical use of evidences remains limited. This paper studies the process of construction of evidences in decisions of innovation policy to understand how evidences were used. It analysis the use of indicators and other evidences through interviews conducted to inquire about the two decisions: an electric mobility policy and a nanotechnology laboratory. Results show indicators and other evidences were brought to decision processes according to their availability and capacity to support the different interests of the actors and
the stakeholders. Their role was influenced by the particular situation of the decision makers. More importantly, the use of persuasive analytical evidences appears to be related with the adversity of the policy context. In addition, research suggests that indicators are one tool among others to foster innovation decisions. In fact, the relatively minor instrumental role of indicators suggests that indicators are mostly a complementary instrument of decision. When used relevantly, indicators can offer support to a decision. But there are other significant influences that need to be taken into account to understand the specific role indicators and other evidences play, such as the social relations of the decision makers and their emotional-intuitive decisions.

Portable X-ray fluorescence spectrometers (p-XRF) have been used in many fields of application/studies like art, archaeology, heavy metals in soil, rocks and ores characterization, and have been a powerful tool for a rapid non-destructive in-situ analysis, without any sample preparation required. This approach was applied in the present case, to distinguish the origin of the fossil bones of two dinosaur specimens from different localities that were accidentally put together in the museum a few years ago. Fossil bones with sedimentary matrix associated were stored together until today in the collection of Geological Museum (Lisbon) and regarded as one single specimen. One set of bones is part of the holotype MG 5787 of the ankylosaur Dracopelta zbyszweskii, which was discovered at Praia do Sul, and described in 1980, while the other, is an undescribed half skeleton of dacentrurine stegosaur, unearthed in the 1960’s at Atouguia da Baleia, near Peniche (both in the coast of central Portugal, distanced about 100 km from each other). Since both specimens are highly valuable for paleontology, a study was developed with the aim of separating and reconstituting the two specimens. The handheld p-XRF (Genius 9000+7000 from Skyray Instrument) was directly used in the sedimentary matrix when it was separated from the bone, and the measure of the chemical content was performed in the intermediate layer between the surface and the bone, to avoid contaminations. Although the light elements could not be attained, because the analyzer is not equipped with the option of gas charging system, the spectra obtained showed differences mainly in the ratio K/Ca, allowing distinguishing the provenance of the bones (Atouguia or Praia do Sul). These results were compared with chemical analysis obtained with XRF laboratorial equipment and complemented by the mineralogical study through X-ray diffraction (XRD) of the sediments where the bones fossilized. The difference observed in the mineralogical constitution of the sedimentary matrix from the two localities (mainly quartz, calcite, feldspars and micas with variable content) explains the variation in the values found for the ratio K/Ca (<0.5 for Atouguia and >>1 for Praia do Sul). The data obtained will be presented and discussed focusing on the importance of using a portable X-ray fluorescence analyzer applied to the reconstitution of dinosaur fossils that proved to be very useful in the present case.

The usability of requirements engineering (RE) techniques has been recognised as a key factor for their successful adoption by industry. RE techniques must be accessible to stakeholders with different backgrounds, so they can be empowered to effectively and efficiently contribute to building successful systems. When selecting an appropriate requirements engineering technique for a given context, one should consider the usability supported by each of the candidate techniques. The first step towards achieving this goal is to gather the best evidence available on the usability of RE approaches by performing a systematic literature review, to answer one research question: How is the usability of requirements engineering techniques and tools addressed? We systematically review articles published in the Requirements Engineering Journal, one of the main sources for mature work in RE, to motivate a research roadmap to make RE approaches more accessible to stakeholders with different backgrounds.

The teacher’s knowledge has long been viewed as a strong influence on the students’ learning. Several authors have sought to develop procedures to assess this knowledge, but this has proved to be a complex task. In this paper I present an outline of a conceptualization to analyze the teacher's knowledge, based on the model of the Knowledge for Teaching Mathematics with Technology (KTMT) and a set of tasks. These tasks are chosen by the teacher among the ones he prepared for his students taking into account the potential of the tasks to take advantage of the technology’s potential. The analyze of the teacher’s KTMT is based on the characteristics of the tasks chosen by the teacher; the balance established between the representations provided by the technology that the tasks advocate; the way how the tasks pay attention to the new issue of seeking for a suitable viewing window; and also the way how the tasks take into account the expectable difficulties of the students in the process of looking for the window.

The integration of the graphing calculator in mathematical activity encourages students to express many of their processes and ways of thinking. Since some of the activities at the high school level are carried out with the graphing calculator, we intend to investigate the contribution of this resource to promote the learning of nonlinear continuous models in the 11th grade. By adopting a qualitative methodology, we collected and analysed the students‟ writing productions. At first, students used to present the information given by the calculator with no justification. As they acquire skills in the use of this resource, they usually set up the viewing window in order to visualize the graphical representations of functions that model the problem situation they are working on and also relate the different existing menus in the study of those functions characteristics. Such procedures make students to present the data collected in the calculator with a justification of their arguments and a validation of their conjectures.

Computers and technology can play a key role in supporting learning, namely for students with special educational needs. Nevertheless, despite the emphasis the society puts on the use of technology and its fast proliferation in the area of education, few initiatives focus on the specific needs of children with disabilities. Motivated by this gap, this research work proposes a computer assisted education application that targets to teach talking and reading through games. The work described herein was carried out in close cooperation with - , a child-care institution that works with children with distinct growth disorders, namely the Down syndrome.

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