Assessing the Performance of the Gsimcli Homogenisation Method with Precipitation Monthly Data from the COST-HOME Benchmark

Ribeiro, S., Caineta, J., & Costa, A. C. (2017). Assessing the Performance of the Gsimcli Homogenisation Method with Precipitation Monthly Data from the COST-HOME Benchmark. In J. J. Gómez-Hernández, J. Rodrigo-Ilarri, E. Cassiraga, M. E. Rodrigo-Clavero, & J. A. Vargas-Guzmán (Eds.), Geostatistics Valencia 2016 (pp. 909-918). (Quantitative Geology and Geostatistics; Vol. 16). Springer. DOI: 10.1007/978-3-319-46819-8_63 ----------------------------- The authors gratefully acknowledge the financial support of Fundação para a Ciência e Tecnologia (FCT), Portugal, through the research project PTDC/GEO-MET/4026/2012 (“GSIMCLI – Geostatistical simulation with local distributions for the homogenization and interpolation of climate data”).Nowadays, climate data series are used in so many different studies that their importance implies the essential need of good data quality. For this reason, the process of homogenisation became a hot topic in the last decades, and many researchers have focused on developing efficient methods for the detection and correction of inhomogeneities in climate data series. This study evaluates the efficiency of the gsimcli homogenisation method, which is based on a geostatistical simulation approach. For each instant in time, gsimcli uses the direct sequential simulation algorithm to generate several equally probable realisations of the climate variable at the candidate station’s location, disregarding its values. The probability density function estimated at the candidate station’s location (local probability density functions (PDF)), for each instant in time, is then used to verify the existence of inhomogeneities in the candidate time series. When an inhomogeneity is detected, that value is replaced by a statistical value (correction parameter) derived from the estimated local PDF. In order to assess the gsimcli efficiency with different implementation strategies, we homogenised monthly precipitation data from an Austrian network of the COST-HOME benchmark data set (COST Action ES0601, Advances in homogenization methods of climate series: an integrated approach – HOME). The following parameters were tested: grid cell size, candidate order in the homogenisation process, local radius parameter, detection parameter and correction parameter. Performance metrics were computed to assess the efficiency of gsimcli. The results show the high influence of the grid cell size and of the correction parameter in the method’s performance.authorsversionpublishe

Material model assessment in Ti6Al4V machining simulations with FEM

Ti6Al4V alloy is a well-known difficult-to-cut material used in different industrial applications, to achieve the expected component quality, proper definition and control of the machining process parameters must be accomplished. To address this problem, simulations with finite element method (FEM) seem to be an interesting engineering tool to model and optimize machining processes. Nevertheless, the model capability in capturing the behaviour observed in real machining processes is associated with the definition of the model and parameters that describe the workpiece flow stress. This contribution aimed to study the performance of built-in AdvantEdge-2DTMmaterial laws applied in Ti6Al4V orthogonal cutting simulations under dry conditions. The numerical models were created under three levels of cutting speed, a constant feed rate and depth-of-cut, a variable tool rake angle (of 20° and -6°/0 °), but also using four Ti6Al4V constitutive laws, namely, one suggested in AdvantEdgeTM library, a Johnson- Cook (JC) model, a Power law (PL) and a PL coupled with ductile damage model. Experimental results were used to assess the numerical models’ accuracy in predicting the machining forces and metal chips. Satisfactory results regarding the machining forces prediction were achieved with all material laws, yet when the damage criterion was coupled with the constitutive laws (PLD and AE standard material law), the simulations were also were able to achieve the expected chip morphology (serrated metal chips). Keywords: Ti6Al4V, AdvantEdge, orthogonal cutting, power law, Johnson-Cook material model, machining forces, saw-tooth chips.publishe

From fibroblasts to cardiomyocytes and beyond

This oral presentation was part of the PhD project of A.J. Duarte at ICBAS (UP).From Fabry disease causing effect to personalised cell model of cardiomyocytes and future mutation correction applying a prime-editing approach.CECA, INSA, and also funded by the Fundação para a Ciência e Tecnologia: (FCT) Project Grant: PTDC/BIM MEC/4762/2014 (2016)info:eu-repo/semantics/publishedVersio

Mobilidade de trabalhadores portugueses no sector da construção civil e obras públicas entre o norte de Portugal e a Galiza

European Employment ServicesUniversidade do Minho Escola de Economia e GestãoUniversidade de Vig

Intelligent machining methods for Ti6Al4V: a review

Digital manufacturing is a necessity to establishing a roadmap for the future manufacturing systems projected for the fourth industrial revolution. Intelligent features such as behavior prediction, decision- making abilities, and failure detection can be integrated into machining systems with computational methods and intelligent algorithms. This review reports on techniques for Ti6Al4V machining process modeling, among them numerical modeling with finite element method (FEM) and artificial intelligence- based models using artificial neural networks (ANN) and fuzzy logic (FL). These methods are intrinsically intelligent due to their ability to predict machining response variables. In the context of this review, digital image processing (DIP) emerges as a technique to analyze and quantify the machining response (digitization) in the real machining process, often used to validate and (or) introduce data in the modeling techniques enumerated above. The widespread use of these techniques in the future will be crucial for the development of the forthcoming machining systems as they provide data about the machining process, allow its interpretation and quantification in terms of useful information for process modelling and optimization, which will create machining systems less dependent on direct human intervention.publishe

Bioinspired architectures toward improving damage resistance on CFRP laminates

Carbon fibre reinforced polymers (CFRP) are widely used in advanced applications due to their high performance and low weight, however, under certain conditions, they tend to develop internal damages that may compromise the component performance in service. Low velocity impact (LVI) events are one of the most common and dangerous solicitations that CFRP laminates must face during their life time, under these conditions they tend to develop so-called barely visible impact damages (BVID) that may propagate in service. To improve damage tolerance to LVI events, three new bioinspired CFRP laminates were developed and their mechanical properties and impact behaviour were compared to a typical aeronautic standard laminate in this work. All these studied laminates, having approximately the same thickness of 4 mm, were produced by vacuum bag infusion and observed under scanning electron microscopes (SEM) for assessing their processing quality. Tensile, interlaminar shear strength (ILSS) and LVI tests were performed in order to evaluate their Young’s modules, global delamination resistance and impact response. LVI tests were performed for all laminates at the four different impact energy levels of 13.5, 25, 40 and 80 J and damage shape and areas were subsequentially evaluated by ultrasonic C-scan. SEM observations and the good agreement between theoretical and experimental Young’s modules results demonstrated a processing quality. ILSS results have shown that the bioinspired hybrid laminate (HYB) presented better global resistance to delamination when compared to the other laminates. LVI tests and C-scan inspection have also demonstrated that HL and HL_S laminates exhibited higher resistance to damage propagation and smaller damaged area, respectively.FCT, Programa MIT Portugal, projeto “IAMAT – Introduction of advanced materials technologies into new product development for the mobility industries

The Potential of Tree and Shrub Legumes in Agroforestry Systems

Climate variability and changes are utmost important primary drivers of biological processes. They are intimately associated with a wide array of abiotic stresses, highlighting the vulnerability of ecosystems and endangering biodiversity. Nitrogen‐fixing trees and shrubs (NFTSs) constitute a unique group of plants for their wide range of applications at the environmental, social and economic levels. In this chapter, we review and analyse the potential of this group of legumes in agroforestry towards sustainable agriculture in Africa. In the first part, the intertwined pillar of sustainable agriculture is brought forward under the context of growing population and climate changes. The second part addresses general aspects of legumes, including botany and the symbiosis with rhizobia. The third part includes the application of NFTS as N‐fertilizers in agroforestry, highlighting the importance of an accurate choice of the crop(s)/NFTS combination(s) and cropping type (intercropping, multistrata or fallows). The implementation of agroforestry systems with NFTS should be supported by fundamental research strategies such as stable isotopes and systems biology and preceded by experimental assays, in order to identify the factors promoting N‐losses and to design appropriate management strategies that synchronize legume‐N availability with the crop demand

Thin veils strategically interleaved to reduce low velocity damages on CFRP

Low velocity impact (LVI) events on carbon fibre reinforced polymers (CFRP) are one of the most problematic issues in composite applications for advanced markets, such as aeronautic, aerospace and army. Due to their own brittleness and layer-by-layer nature, when exposed to LVI solicitations, composites tend to develop internal damages that may be barely visible at naked eye. The high complex field of internal stresses developed in composite laminates during impact usually causes crack initiation and defects between layers, which may propagate (delamination) due to the low toughness that this unreinforced resin rich region exhibits. In this work, to try minimizing this propagation problem, thin veils of different materials (glass, carbon, aramid and polyester), were interleaved between different layers of a carbon/epoxy laminate typically used to produce aircraft components. In addition, to decide between which layers could be better interleave the above referred veils a theoretical study was carried out to evaluate the stresses distribution across laminate thickness when a bending moment is applied, on a carbon/epoxy laminate under study. The new carbon/epoxy laminates using the thin interleaved veils were produced by vacuum bag infusion and their mechanical characteristics and LVI responses compared with those obtained on a non-interleaved one produced in the same processing conditions. Interlaminar shear strength (ILSS) and LVI tests at four different energy impact levels were performed in order to evaluate the respective characteristics of the laminates, their damage tolerance and impact response. All laminates studied were also observed under scanning electron microscopes (SEM) for assessing their processing quality.FCT, Programa MIT Portugal, projeto “IAMAT – Introduction of advanced materials technologies into new product development for the mobility industries

Effects of Resistance Exercise on Endothelial Progenitor Cell Mobilization in Women

This study aimed to determine the effect of a single bout of resistance exercise at different intensities on the mobilization of circulating EPCs over 24 hours in women. In addition, the angiogenic factors stromal cell-derived factor 1 (SDF-1α), vascular endothelial growth factor (VEGF), hypoxia-inducible factor 1-alpha (HIF-1α) and erythropoietin (EPO) were measured as potential mechanisms for exercise-induced EPCs mobilization. Thirty-eight women performed a resistance exercise session at an intensity of 60% (n = 13), 70% (n = 12) or 80% (n = 13) of one repetition maximum. Each session was comprised of three sets of 12 repetitions of four exercises: bench press, dumbbell curl, dumbbell squat, and standing dumbbell upright row. Blood was sampled at baseline and immediately, 6 hours, and 24 hours post-exercise. Circulating EPC and levels of VEGF, HIF-1α and EPO were significantly higher after exercise (P \u3c 0.05). The change in EPCs from baseline was greatest in the 80% group (P \u3c 0.05), reaching the highest at 6 hours post-exercise. The change in EPCs from baseline to 6 hours post-exercise was correlated with the change in VEGF (r = 0.492, P = 0.002) and HIF-1α (r = 0.388, P = 0.016). In general, a dose-response relationship was observed, with the highest exercise intensities promoting the highest increases in EPCs and angiogenic factors

Carbon nanotubes based multi-directional strain sensor

In this work a new carbon nanotubes (CNT) based multi-directional strain sensor capable of quantifying and indicate strain direction is foreseen. This work investigates the electromechanical behavior of an aligned CNT sensing patch strained at 45◦ in order to validate its multi-directional sensing capability. Vertically aligned CNT forests are produced by chemical vapor deposition (CVD) and then mechanically knocked down onto polyimide (PI) films. Two configurations, diamond (D sample) and square (Sq sample), are considered. The relative electrical resistance (ΔR/R0) and the electrical anisotropy (RB/RA) upon strain increments are analyzed and compared to previous work results (0◦ and 90◦ strain direction). Both 45◦ samples, D and Sq, are sensitive to strain. A correlation between electrical anisotropy behavior and strain direction (0◦, 45◦ and 90◦) is established. The results show that with only an aligned CNT small patch it is possible to quantify and indicate strain in three directions.This work was partially funded under the project “IAMAT – Introduction of advanced materials technologies into new product development for the mobility industries”, with reference MITP-TB/PFM/0005/2013, under the MIT-Portugal program exclusively financed by FCT – Fundação para a Ciência e Tecnologia. This work was also co-financed by national funds through FCT – Fundação para a Ciência e Tecnologia, with the scope of projects with references UIDB/05256/2020 and UIDP/05256/2020”