Hybrid neural network based models for evapotranspiration prediction over limited weather parameters

Evapotranspiration can be used to estimate the amount of water required by agriculture projects and green spaces, playing a key role in water management policies that combat the hydrological drought, which assumes a structural character in many countries. In this context, this work presents a study on reference evapotranspiration (ETo) estimation models, having as input a limited set of meteorological parameters, namely: temperature, humidity, and wind. Since solar radiation (SR) is an important parameter in the determination of ETo, SR estimation models are also developed. These ETo and SR estimation models compare the use of Artificial Neural Networks (ANN), Long Short Term Memory (LSTM), Gated Recurrent Unit (GRU), Recurrent Neural Network (RNN), and hybrid neural network models such as LSTM-ANN, RNN-ANN, and GRU-ANN. Two main approaches were taken for ET(o )estimation: (i) directly use those algorithms to estimate ETo, and (ii) estimate solar radiation first and then use that estimation together with other meteorological parameters in a method that predicts ETo. For the latter case, two variants were implemented: the use of the estimated solar radiation as (ii.1) a feature of the neural network regressors, and (ii.2) the use of the Penman-Monteith method (a.k.a. FAO-56PM method, adopted by the United Nations Food and Agriculture Organization) to compute ETo, which has solar radiation as one of the input parameters. Using experimental data collected from a weather station (WS) located in Vale do Lobo (Portugal), the later approach achieved the best result with a coefficient of determination (R-2) of 0.977. The developed model was then applied to data from eleven stations located in Colorado (USA), with very distinct climatic conditions, showing similar results to the ones for which the models were initially designed ((R2) > 0.95), proving a good generalization. As a final notice, the reduced-set features were carefully selected so that they are compatible with free online weather forecast services.info:eu-repo/semantics/publishedVersio

When Politicians Talk About Politics: Identifying Political Tweets of Brazilian Congressmen

Since June 2013, when Brazil faced the largest and most significant mass protests in a generation, a political crisis is in course. In midst of this crisis, Brazilian politicians use social media to communicate with the electorate in order to retain or to grow their political capital. The problem is that many controversial topics are in course and deputies may prefer to avoid such themes in their messages. To characterize this behavior, we propose a method to accurately identify political and non-political tweets independently of the deputy who posted it and of the time it was posted. Moreover, we collected tweets of all congressmen who were active on Twitter and worked in the Brazilian parliament from October 2013 to October 2017. To evaluate our method, we used word clouds and a topic model to identify the main political and non-political latent topics in parliamentarian tweets. Both results indicate that our proposal is able to accurately distinguish political from non-political tweets. Moreover, our analyses revealed a striking fact: more than half of the messages posted by Brazilian deputies are non-political.Comment: 4 pages, 7 figures, 2 table

Grazing hinders seed dispersal during crop failure in a declining oak woodland

Masting, the synchronized production of variable quantities of seeds, is a global phenomenon in diverse ecosystems, including treed grazing systems where trees and grazing animals coexist. This phenomenon can be interspersed with years of extreme crop failure, whose frequency and unpredictability are increasing. Yet, the combined impact of crop failure and grazing on seed dispersal and seed-to-seedling transition remains poorly understood. To address this concern, we investigated rodent-mediated cork-oak (Quercus suber) acorn predation, dispersal, and seedling emergence in cattle grazed and non-grazed areas in central Portugal during years with contrasting masting seasons. We found that the acorns supplied in the crop failure year were dispersed more rapidly and over longer distances than those supplied in the crop success year when other acorns were naturally available. The crop failure year also had 83 % more dispersal events and 84 % more predated acorns than the reproductive success year. However, the higher acorn predation was offset by a 2.4-fold higher percentage of unpredated dispersed acorns recruiting into seedlings. Both years ended up recruiting a similar number of seedlings. Acorns emerged seedlings 3.4 times farther in the crop failure year than in the crop success year. Cattle grazing was the main constraint on seed dispersal distance by rodents, reducing it by 53 %. Our study provides empirical evidence that cattle grazing modulates how an extreme crop failure year can surprisingly be an opportunity for the few existing acorns to have seedlings established farther apart than in a crop success year. If we are to better manage and preserve the high conservation and socio-economic value of Mediterranean cork oak woodlands in the face of climate change, we must prioritize fecund trees and carefully manage seed dispersal factors such as cattle grazing, particularly during years of crop failure.info:eu-repo/semantics/publishedVersio

Relatório de Estágio Profissionalizante - Sport Lisboa e Benfica/Escolas de Futebol Benfica

O presente documento consiste na elaboração do relatório final do Estágio Profissionalizante, realizado como parte integrante e conclusiva do Mestrado em Ciências do Desporto, Especialidade de Treino Desportivo, da Escola Superior de Educação Comunicação e Desporto (ESECD) do Instituto Politécnico da Guarda (IPG). O Estágio Profissionalizante realizou-se na Escola de Futebol do Sport Lisboa e Benfica, em Lisboa, na época desportiva de 2014/2015, tendo como objetivo buscar competências que me permitissem evoluir enquanto treinador do futebol através da vivência em contexto real de trabalho numa das mais prestigiadas instituições a nível mundial. A escolha da Escola de Futebol do Sport Lisboa e Benfica, enquanto Instituição acolhedora para a realização deste estágio deveu-se aos feedbacks de alguns amigos que tenho na instituição, relativamente à forma de pensar e operacionalizar o treino, não obstante também o facto de se tratar de um dos melhores clubes de sempre, a nível mundial. Este trabalho encontra-se dividido em quatro capítulos, para além da Introdução e das Conclusões/Reflexões Finais. No primeiro é feita uma caraterização da Escola de Futebol do Sport Lisboa e Benfica, sendo também referidos os recursos disponíveis. No segundo inclui-se o plano de estágio, onde constam as tarefas a desempenhar assim como os objetivos que me propus concretizar. No terceiro é realizada uma revisão bibliográfica acerca do futebol e dos aspetos relevantes para a formação desportiva de crianças e jovens. No quarto e último capítulo deste relatório são descritas as atividades desenvolvidas ao longo do estágio e é ainda apresentado o projeto de investigação desenvolvido no âmbito do estágio. O estágio profissionalizante revela-se, de facto, como uma ótima oportunidade de aprendizagem, promotor de diversas aquisições e capaz de conferir um desenvolvimento de competências profissionais e pessoais, constituindo-se como um excelente ponto de partida para uma futura integração no mercado de trabalho na área do treino desportivo

Modeling the functional network of primary intercellular Ca2+^{2+} wave propagation in astrocytes and its application to study drug effects

We introduce a simple procedure of multivariate signal analysis to uncover the functional connectivity among cells composing a living tissue and describe how to apply it for extracting insight on the effect of drugs in the tissue. The procedure is based on the covariance matrix of time resolved activity signals. By determining the time-lag that maximizes covariance, one derives the weight of the corresponding connection between cells. Introducing simple constraints, it is possible to conclude whether pairs of cells are functionally connected and in which direction. After testing the method against synthetic data we apply it to study intercellular propagation of Ca$^{2+}$ waves in astrocytes following an external stimulus, with the aim of uncovering the functional cellular connectivity network. Our method proves to be particularly suited for this type of networking signal propagation where signals are pulse-like and have short time-delays, and is shown to be superior to standard methods, namely a multivariate Granger algorithm. Finally, based the statistical analysis of the connection weight distribution, we propose simple measures for assessing the impact of drugs on the functional connectivity between cells.Comment: 14 pages, 12 figure

Tree type and forest management effects on the structure of strem wood following wilfires

Wildfires are an increasingly common disturbance influencing wood recruitment to streams, and thereby affecting their physical and biological condition. Mediterranean countries such as Portugal, where more than 25% of the land area has burned since 1990, are ideal areas to study impacts of wildfire effects on streams. We evaluated the physical structure of 2206 downed wood pieces (DWP) across 27 first- to third-order streams in central Portugal, all of which had experienced recent wildfires. The streams flowed through monospecific upland forests of Eucalyptus, Maritime pines, or Cork oaks and were fringed by a mixture of riparian tree species. DWP structure differed between tree types and between burned and unburned pieces. Post-fire timber-production forests (Maritime pines and Eucalyptus) contributed a higher quantity of thinner, longer and straighter DWP to streams than Cork oak stands. Pieces from Maritime pines had more rootwads and branches than DWP from the other tree types. Pieces from Cork oak and riparian species generally had a bent form, were shorter and had no rootwads. Burned DWP in streams were often from riparian trees. Relative to unburned DWP, the burned DWP occurred more frequently, were larger and straighter, had branches less often, and were more decayed. With more complex branches, rootwads, and a larger diameter, inputs from burned Maritime pine forests are more likely to change stream hydraulics and habitat complexity, relative to inputs from Eucalyptus forests with their simpler structure. This study shows that, less than a decade after wildfires, structure of downed wood in and near streams is strongly influenced by wildfire, but also still reflects intrinsic species characteristics and respective silviculture practices, even after the effects of fire have been accounted for. Under an anticipated shift in landscape cover with higher shrubland proportions and more mixing of Maritime pine and Eucalyptus forests, our results suggest that instream large wood will become scarcer and more structurally homogeneous

Carnivores cross irrigation canals more often through overpasses than through culverts

As rainfall becomes scarcer or more erratic, we rely more on irrigation systems for agricultural and human water provision. Impacts of irrigation canals such as the barrier effect on wildlife movements are poorly documented. Although canal culverts and overpasses can be used by wildlife, little is known about their crossing behavior to guide barrier effect mitigation efforts. Over seven years, we recorded medium-sized carnivore crossings by video-surveillance through 30 culverts and 28 overpasses in a large irrigation project in south-central Portugal. We examined the in fl uence of the structures ’ features and landscape con- text on the likelihood of canal crossing. Culvert crossings were positively in fl uenced by the proportion of nearby montado, a high nature value farming system. Overpass crossings were more likely in areas away from paved roads and with more nearby wetlands. Overpasses increased the crossing rates by about 11% relative to culverts and both were crossed more often in land- scapes with evenly distributed land uses. In the project area, 20% of the montado has recently transitioned to irrigated agricul- ture, and wetlands have increased by 43%. It is therefore plausible that the increase in the crossing rate of overpasses relative to culverts will be accentuated. Our study produced the fi rst evidence of a contrast in crossing rates among irrigation canal cross- ing structures. We have shown that the landscape can be a driver of animal crossings but irrigation projects can in turn be trans- formative of the landscape. Broadly, the fact that the deployment of irrigation canals may favor some land uses over others creates a conundrum that needs careful consideration when planning barrier effect mitigation interventions

Effects of grazing pressure on activity and richness of bats in a Portuguese silvo-pastoral system

Background High Nature Value Farmlands (HNVF) harbor species dependent upon habitats maintained by low-intensity farming. Among HNVF, the montado (dehesa in Spain) is a multifunctional system declining due to droughts, pathogens, and increasing grazing pressure. Specifically, grazing pressure leads to compact soils and hinders natural tree regeneration. Regrettably, there is a dearth of information supporting management decisions on the side-effects of high grazing pressure on HNVF-dwelling biodiversity. In particular, little is known about the impact of grazing pressure on bats, a group of species of special conservation concern that may provide key ecosystem services such as biological pest control. Purpose We investigated patterns of activity levels and community composition of insectivorous bats to test the hypothesis that there is a significant relationship between the level of livestock grazing pressure within montado HNVF parcels and patterns of insectivorous bats’ presence and activity. Our specific aims were to (i) assess separately the effects of grazing pressure on bat activity and species composition, (ii) test the predictive significance of key covariates (e.g., insect availability). Methods We conducted this study in 2014 in the Natura 2000 network site “Monfurado”, southern Portugal. This site is specifically acknowledged for its well-preserved montados providing feeding areas for bat species. We quantified acoustically bat flight activity and species richness in farm parcels dominated by cork oak trees. Per parcel, we selected two separate locations (high vs. low grazing pressure) based on landowners’ interviews and grazing pressure indicators, totaling 42 sampling locations. We then used linear mixed-effects modeling to evaluate the effects of grazing pressure and covariates on activity and species richness. Results Bat activity and bat species richness peaked at low grazing pressure locations. Bat activity also increased with tree cover and in locations where livestock grazing signs were old or absent. Conversely, bat activity at low grazing pressure locations decreased with distance to the nearest standing water body. Discussion Our study clearly demonstrated that locations maintained under high grazing pressure within HNVF can have negative consequences for bats, which are acknowledged as good bioindicators of habitat quality. In order to promote better habitat for bats, practitioners should avoid favoring grazing-prone areas (e.g., rotating the location of livestock feeders, drinkers, and gates) across montado HNVF. Broadly, ecosystem services provided by bats for HNVF must be enhanced through sustainability oriented agro-environment schemes under the Economic Community Rural Development Program, including the reduction of stocking density

Email spam detection : a symbiotic feature selection approach fostered by evolutionary computation

Post-print version (prior to journal publication)The electronic mail (email) is nowadays an essential communication service being widely used by most Internet users. One of the main problems affecting this service is the proliferation of unsolicited messages (usually denoted by spam) which, despite the efforts made by the research community, still remains as an inherent problem affecting this Internet service. In this perspective, this work proposes and explores the concept of a novel symbiotic feature selection approach allowing the exchange of relevant features among distinct collaborating users, in order to improve the behavior of anti-spam filters. For such purpose, several Evolutionary Algorithms (EA) are explored as optimization engines able to enhance feature selection strategies within the anti-spam area. The proposed mechanisms are tested using a realistic incremental retraining evaluation procedure and resorting to a novel corpus based on the well-known Enron datasets mixed with recent spam data. The obtained results show that the proposed symbiotic approach is competitive also having the advantage of preserving end-users privacy.The work of P. Cortez and P. Sousa was funded by FEDER, through the program COMPETE and the Portuguese Foundation for Science and Technology (FCT), within the project FCOMP-01-0124-FEDER-022674

ITs in engineering education: joining efforts between SPEE and IGIP

The International Society for Engineering Education (IGIP) and The Portuguese Society for Engineering Education (SPEE), the first being the oldest European Society for Engineering Education in Europe and the second the very young Society for Engineering Education in Portugal, have been intensifying the collaboration between the two societies as well as the exchange and dissemination of information about their relevant activities, whilst promoting understanding and cooperation between their respective members. One possible way is to create joint working groups, open to the members of both societies, on common topics of interest. In fact, both societies already kicked off this activity. The first initiative happened during the 1st World Engineering Education Flash Week (WEE), Lisbon, 2011. The SPEE-IGIP Flash Moment was a one day event integrated in the main Conference, which was dedicated to “Information & Communication Technologies in Engineering Education”. ITs allow the development of different teaching strategies which contribute to enhance the learning outcomes of students. ITs are also particularly suited to develop Life Long Learning tools, in a broad range of Engineering subjects, either open to the general market or oriented to a very specific public. Examples of teaching strategies involving ITs have been addressed during the Flash Moment SPEE-IGIP which took place during WEE, and some are described in detail in the present work