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Publications

2021

Non-verbal Aspects of Collaboration in Virtual Worlds: a CSCW Taxonomy-development Proposal Integrating the Presence Dimension

Authors
Cruz, A; Paredes, H; Morgado, L; Martins, P;

Publication
JOURNAL OF UNIVERSAL COMPUTER SCIENCE

Abstract
Virtual worlds, particularly those able to provide a three-dimensional physical space, have features that make them suitable to support collaborative activities. These features distinguish virtual worlds from other collaboration tools, but current taxonomies of the field of Computer-Supported Cooperative Work do not account for several distinctive features of virtual worlds, namely those related with non-verbal communication. We intended to find out how the use of an avatar, gestures, spatial sounds, etc., influence collaboration in order to be able to include non-verbal communication in taxonomies of the field Computer-Supported Cooperative Work. Several cases of collaboration in virtual worlds are analysed, to find the impact of these non-verbal characteristics of virtual worlds. We proposed adding the concept of Presence to taxonomies of Computer-Supported Cooperative Work and contribute with guidance for future taxonomy development that includes it as a new dimension. This new dimension of Presence is subdivided into "avatar" and "physical space" subdimensions. In turn, these are divided into "physical appearance", "gestures, sounds and animations" and "focus, nimbus and aura"; "environment" and "objects / artefacts". This new taxonomy-development proposal may contribute to inform better design of virtual worlds in support of cooperative work.

2021

BELBIC Based Step-Down Controller Design Using PSO

Authors
Coelho, JP; César, MB; Gonçalves, J;

Publication
OL2A

Abstract
This article presents a comparison between a common type III controller and one based on a brain emotional learning paradigm (BELBIC) parameterized using a particle swarm optimization algorithm (PSO). Both strategies were evaluated regarding the set-point accuracy, disturbances rejection ability and control effort of a DC-DC buck converter. The simulation results suggests that, when compared to the common controller, the BELBIC leads to an increase in both set-point tracking and disturbances rejection ability while reducing the dynamics of the control signal.

2021

A Simple Procedure to Estimate Reference Evapotranspiration during the Irrigation Season in a Hot-Summer Mediterranean Climate

Authors
Rodrigues, GC; Braga, RP;

Publication
SUSTAINABILITY

Abstract
The Food and Agricultural Organization of the United Nations (FAO) Penman-Monteith (PM) method is widely regarded as the most effective reference evapotranspiration (ETo) estimator; however, it requires a wide range of data that may be scarce in some rural regions. When feasible relative humidity, solar radiation and wind speed data are unavailable, a temperature-based method may be useful to estimate ETo and provide suitable data to support irrigation management. This study has evaluated the accuracy of two ETo estimations methods: (1) a locally and monthly adjusted Hargreaves-Samani (HS) equation; (2) a simple procedure that only uses maximum temperature and a temperature adjustment coefficient (MaxTET). Results show that, if a monthly adjusted radiation adjustment coefficient (k(Rs)) is calibrated for each site, acceptable ETo estimations (RMSE and R-2 equal to 0.79 for the entire region) can be achieved. Results also show that a procedure to estimate ETo based only on maximum temperature performs acceptably, when compared with ETo estimation using PM equation (RMSE = 0.83 mm day(-1) and R-2 = 0.77 for Alentejo). When comparing these results with the ones attained when adopting a monthly adjusted HS method, the MaxTET procedure proves to be an accurate ETo estimator. Results also show that both methods can be used to estimate ETo when weather data are scarce.

2021

Integrative approach - QR-Code on tax relevant documents in Portugal - Validation and Exequibility

Authors
Marques, A; Reis, L;

Publication
PROCEEDINGS OF 2021 16TH IBERIAN CONFERENCE ON INFORMATION SYSTEMS AND TECHNOLOGIES (CISTI'2021)

Abstract
The legal framework for the conduct of the work, derives from the Decree Law No. 28/2019 of February 15, combined with Ordinance 195/2020 of 13 August and the VAT Code, as well as the amendment to the proposal of Law No. 61/XIV, which postponed to 2022 the mandatory printing of the QR-Code on the invoice and documents fiscally relevant. The objective of the paper focuses on the presentation of a validation of a multidisciplinary and integrative approach, which was developed to analyze the impact on the different stakeholders, when introducing the QR-Code in the relevant tax documents in Portugal. The methodology used was Design Science Research. The paper's contributions are based on the presentation and validation of the Approach using survey design, with the aim of assessing its suitability and feasibility with the various stakeholders (Software Producers/Installers, Hauliers, Certified Accountants, Tax and Customs Authority, Taxpayers and Buyers). In this way, it was possible to assess the expectations of the stakeholders in face of the new legal framework, as well as the impact that these legislative changes will cause in an organizational context.

2021

Irriman Platform: Enhancing Farming Sustainability through Cloud Computing Techniques for Irrigation Management

Authors
Forcén-Muñoz, M; Pavón-Pulido, N; López-Riquelme, JA; Temnani-Rajjaf, A; Berríos, P; Morais, R; Pérez-Pastor, A;

Publication
Sensors

Abstract
Crop sustainability is essential for balancing economic development and environmental care, mainly in strong and very competitive regions in the agri-food sector, such as the Region of Murcia in Spain, considered to be the orchard of Europe, despite being a semi-arid area with an important scarcity of fresh water. In this region, farmers apply efficient techniques to minimize supplies and maximize quality and productivity; however, the effects of climate change and the degradation of significant natural environments, such as, the “Mar Menor”, the most extent saltwater lagoon of Europe, threatened by resources overexploitation, lead to the search of even better irrigation management techniques to avoid certain effects which could damage the quaternary aquifer connected to such lagoon. This paper describes the Irriman Platform, a system based on Cloud Computing techniques, which includes low-cost wireless data loggers, capable of acquiring data from a wide range of agronomic sensors, and a novel software architecture for safely storing and processing such information, making crop monitoring and irrigation management easier. The proposed platform helps agronomists to optimize irrigation procedures through a usable web-based tool which allows them to elaborate irrigation plans and to evaluate their effectiveness over crops. The system has been deployed in a large number of representative crops, located along near 50,000 ha of the surface, during several phenological cycles. Results demonstrate that the system enables crop monitoring and irrigation optimization, and makes interaction between farmers and agronomists easier.

2021

Optimising grapevine summer stress responses and hormonal balance by applying kaolin in two Portuguese Demarcated Regions

Authors
Bernardo, S; Dinis, LT; Luzio, A; Machado, N; Goncalves, A; Vives Peris, V; Pitarch Bielsa, M; Lopez Climent, MF; Malheiro, AC; Correia, C; Gomez Cadenas, A; Moutinho Pereira, J;

Publication
OENO ONE

Abstract
In Mediterranean-like climate areas, field-grown grapevines are typically exposed to severe environmental conditions during the summer season, which can negatively impact the sustainability of viticulture. Despite the short-term mitigation strategies available nowadays to cope with climate change, little is known regarding their effectiveness in different demarcated winegrowing regions with differing climate features. Hence, we applied a kaolin suspension (5 %) to Touriga-Franca (TF) and Touriga-Nacional (TN) grapevine varieties located in two Portuguese demarcated regions (Alentejo and Douro) with different mesoclimates to study its effect on the physiological performance, hormonal balance and ABA-related grapevine leaf gene expression during the 2017 and 2018 growing seasons. Data show that 2017 was warmer than 2018 due to the occurrence of two heatwaves in both locations, highlighting the protective effect of kaolin application under severe environmental conditions. In the first study year, at midday, kaolin enhanced water use efficiency (23 % in Douro and 13 % in Alentejo), carbon assimilation rates (PN; 72 % in Douro and 25 % in Alentejo), and the soluble sugar content of grapevine leaves, while decreasing the accumulation of plant growth regulators (ABA, IAA, and SA) during the ripening stage. The results show an up-regulation of ABA biosynthesis-related genes (VvNCED) in TF treated vines from the Douro vineyard mainly in 2017, suggesting an increased stress response under severe summer conditions. Additionally, kaolin triggered the expression of ABA-responsive genes (VvHVA22a and VvSnRK2.6) mainly in TF, indicating different varietal responses to kaolin application under fluctuating periods of summer stress.

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