Nowadays, simulation tools are available for calculating the thermal loads of multiple rooms of buildings, for given inputs. However, due to inaccuracies or uncertainties in some of the input data (e.g., thermal properties, air infiltrations flow rates, building occupancy), the evaluated thermal load may represent no more than just an estimate of the actual thermal load of the spaces. Accordingly, in certain practical situations, simplified methods may offer a more reasonable trade-off between effort and results accuracy than advanced software. Hence, despite the advances in computing power over the last decades, simplified methods for the evaluation of thermal loads are still of great interest nowadays, for both the practicing engineer and the graduating student, since these can be readily implemented or developed in common computational-tools, like a spreadsheet.The method of Mackey and Wright (M&W) is a simplified method that upon values of the decrement factor and time lag of a wall (or roof) estimates the instantaneous rate of heat transfer through its indoor surface. It assumes cyclic behaviour and shows good accuracy when the excitation and response have matching shapes, but it involves non negligible error otherwise, for example, in the case of walls of high thermal inertia.The aim of this study is to develop a simplified procedure that considerably improves the accuracy of the M&W method, particularly for excitations that noticeably depart from the sinusoidal shape, while not introducing a need for an excessive volume of data or complexity in the production of results.In the first simplified procedure discussed in the paper, a full-featured excitation is decomposed into a Fourier series and then the wall's thermal behaviour is reconstructed from the application of the M&W method to each of the N sinusoidal components. Even though this established approach can lead to the most accurate results, given a sufficiently high N, it requires the knowledge of the decrement factor and time lag associated to each component of the Fourier series, which can represent a considerable amount of data.The chief result of the research though is a novel procedure based on a parameter, γ, that weigh-averages the approximate solution obtained by considering a single term Fourier decomposition of the excitation and the solution by considering the actual excitation. The procedure is more accurate than the original M&W method and will be of interest to researchers with the means of generating values of γ for the walls which the end users of their research are interested in. It provides promising results for walls ranging from massive to negligible mass. It has been noticed that while using the same values of γ that had been optimized for the wall facing east, acceptable results are also obtained when altered external excitations are imposed, namely due to intermittency of the direct solar radiation or due to a distinct value of the external heat transfer coefficient. © 2015 Elsevier Ltd.

Abstract Probabilistic fatigue models are required to account conveniently for several sources of uncertainty arising in the prediction procedures for structural details, such as the scatter in material behaviour. In this paper, a procedure to derive probabilistic S-N fields for structural details [1] is applied to a notched geometry with elliptic central hole made of puddle iron from the Eiffel bridge, based on the local approaches supported by the probabilistic ɛa–N or Smith–Watson–Topper (SWT)–N fields [1,2]. This procedure suggests an extension of the fatigue crack propagation model proposed by Noroozi et al. [3,4] to structural details, in order to cover both the fatigue crack initiation and fatigue crack propagation, based on local strain approaches to fatigue. Both fatigue crack initiation and fatigue crack propagation mechanisms are accounted for in the proposed approach. The numerical results are compared with available experimental S-N fatigue data for the notched plate under consideration.

The wind energy production is a growing industry and the energy produced is renewable and environmentally cleaner than most of the energy production systems. The supports of the wind energy generators may be built with precast concrete elements. The precast solutions for these structures are competitive in comparison to other structural systems. The evolution of the technology for wind energy production shows a clear need for larger wind turbines and longer blades and, consequently, taller towers. The experience also shows that precast concrete solutions increase their competitiveness as the tower height increases. Offshore wind farms have some advantages in relation to onshore ones, which explains recent investments in this area. Also in this case, the durability of concrete in the sea when compared to steel, gives advantages to precast concrete in relation to other structural solutions. This paper shows the evolution of the supports of the wind energy generators and the advantages of the use of precast concrete towers.

This paper presents a remote laboratory linked with mobile devices for real data analysis on the field of power quality. A global system was developed from the power quality analyzer into the human machine interface devoted to the m-learning system. This m-learning system is intended to be used in a long life learning perspective. The developed remote laboratory is a good opportunity for people, even without deep knowledge on the field, to learn power quality principles in an applied way. Since the system is based on real data, is a good approach to give trainees practical knowledge on the field.

The improved characteristics of Tunnel FETs (TFETs) like steep sub-threshold swing and low off-currents make them an attractive choice for low power operations compared to MOSFETs and Multi-gate FETs like FINFETs. Such characteristics are favorable to digital design, but the drain current saturation in their output characteristics can also benefit the analog design. In this paper, it is shown by simulations that analog characteristics as voltage gain, power consumption and bandwidth are improved using TFETs compared to their counterparts, at a sub-22 nm technology node and 0.8 V supply voltage.

Mosasaurs are marine squamates with a 32.5 million-year history from their appearance at 98 Ma to their extinction at the K-Pg boundary (65.5 Ma). Using a database of 43 generic and 94 species-level taxa, we compare the taxonomic diversity and patterns of morphological disparity in mosasaurs with sea level, sea surface temperature, and stable carbon isotope curves for the Upper Cretaceous to explore factors that may have influenced their evolution. No single factor unambiguously accounts for all radiations, diversification, and extinctions; however, the broader patterns of taxonomic diversification and
morphological disparity point to niche differentiation in a “fishing up” scenario under the influence of “bottom-up” selective pressures. The most likely driving force in mosasaur evolution was high productivity in the Late Cretaceous, driven by tectonically controlled sea levels and climatically controlled ocean stratification and nutrient delivery. When productivity collapsed at the end of the Cretaceous, coincident with bolide impact, mosasaurs became extinct.

The present work aims to support tactical and operational planning decisions of reverse logistics systems while considering economical, environmental and social objectives. In the literature, when addressing such systems economical aspects have been often used, while environmental concerns have been only recently emerging. The social component is the one less studied, and rarely the combination of the three concerns has been analyzed. This work address the three objectives and was motivated by the challenge of supporting decisions makers when managing a real case study of a recyclable waste collection system, where strategic decisions on the number and location of depots, vehicles and containers were taken beforehand. Tactical and operational decisions are studied involving the establishment of service areas for each depot and the definition and scheduling of collection routes for each vehicle. Such decisions should represent a compromise solution between the three objectives considered and support a sustainable reverse logistics plan. A multi-objective solution approach based on mixed-integer linear programming models is developed. Trade-offs between the objectives are discussed. Moreover the solutions obtained when each objective is tackled individually are compared between themselves and with the balanced solution.

Os Cursos de Educação e Formação (CEF) foram concebidos tendo presente o elevado número de jovens em situação de abandono escolar, alunos usualmente marcados por experiências de insucesso, em particular a Matemática. O programa de Matemática Aplicada tem em conta esta realidade, tanto ao nível das aprendizagens como das metodologias e das características da avaliação a implementar. Relativamente à avaliação sumativa, é valorizado o trabalho desenvolvido pelo aluno, a sua apresentação, discussão e melhoria. As indicações dadas ao professor afastam-se da opção tradicional do teste de avaliação. O papel do professor na gestão curricular não é contudo negligenciado, sendo valorizada a adequação das propostas às características dos alunos. Este estudo pretende analisar as concepções de alunos e professores relativamente à avaliação sumativa, procurando compreender a forma como se influenciam mutuamente e como afectam a prática de avaliação do professor. Foram realizados três estudos de caso, incidindo sobre alunos e respectivo professor. Os dados foram recolhidos através de entrevistas, observação de aulas e recolha documental. Os resultados alcançados sugerem uma forte valorização dos testes por parte dos alunos, sendo notória a influência sobre as opções assumidas pelo professor. Determinantes parecem ser as concepções dos alunos relativamente ao papel de alunos e professores no que à avaliação respeita.

We present a stratigraphic log supporting a preliminary magnetostratigraphy of a Tithonian–Berriasian section in Porto da Calada (Portugal). Based on biostratigraphy and reversed and normal magnetostratigraphy, the location of the Tithonian–Berriasian boundary is tentatively located at ca. 52 m, not in disagreement
with former proposals. Due to the occurrence of later remagnetization (diagenesis), the magnetostratigraphic definition of the Tithonian–Berriasian section at the Cabo Espichel (Portugal) location was not able to be established.

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Os cursos de Educação e Formação de Adultos prevêem uma avaliação que se afasta do tradicionalmente implementado nas escolas, propiciando o emergir de processos de mudança. Neste estudo analisa-se a forma como um formador concretiza a avaliação, ponderando continuidades e descontinuidades relativamente a práticas anteriores, com a intenção de caracterizar o inerente processo de mudança e os factores que o influenciam.
As conclusões obtidas sugerem um processo de mudança complexo, cuja necessidade não é verdadeiramente reconhecida, e onde parece ser determinante a reflexão do formador sobre os formandos, o contexto existente e algumas opções ao nível local da escola.