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Freshwater ecosystems are disproportionally important for biodiversity conservation, as they support more than 9% of known animal species while representing less than 1% of the Earth’s surface. However, the vast majority of the threats (99%, or 826 out of 837) identified by the International Union for Conservation of Nature Red List of Threatened Species known to affect the 434 known freshwater-dependent fish and lampreys of Europe are not supported by validated published scientific knowledge. This general lack of information about freshwater-dependent fish and lamprey species may have deleterious effects on species conservation, and additional funding is required to fill baseline knowledge gaps.
Paulo Branco; Pedro Segurado; Maria Costa; Afonso Teixeira; José Santos; Maria Ferreira; Gonçalo Duarte. Knowledge Gaps in the Definition of Threats for the Red List Assessment of European Freshwater-Dependent Fish Species. Biology 2021, 10, 680 .
AMA StylePaulo Branco, Pedro Segurado, Maria Costa, Afonso Teixeira, José Santos, Maria Ferreira, Gonçalo Duarte. Knowledge Gaps in the Definition of Threats for the Red List Assessment of European Freshwater-Dependent Fish Species. Biology. 2021; 10 (7):680.
Chicago/Turabian StylePaulo Branco; Pedro Segurado; Maria Costa; Afonso Teixeira; José Santos; Maria Ferreira; Gonçalo Duarte. 2021. "Knowledge Gaps in the Definition of Threats for the Red List Assessment of European Freshwater-Dependent Fish Species." Biology 10, no. 7: 680.
Existing megawatt-scale photovoltaic (PV) power plant producers must understand that simple and low-cost Operation and Maintenance (O&M) practices, even executed by their own personal and supported by a comparison of field data with simulated ones, play a key role in improving the energy outputs of the plant. Based on a currently operating 18 MW PV plant located in an under-developing South-Asia country, we show in this paper that comparing real field data collected with simulated results allows a central vision concerning plant underperformance and valuable indications about the most important predictive maintenances actions for the plant in analysis. Simulations using the globally recognized software PVSyst were first performed to attest to the overall power plant performance. Then, its energy output was predicted using existing ground weather data located at the power plant. Compared with the actual plant’s annual energy output, it was found that it was underperforming by −4.13%, leading to a potential monetary loss of almost 175,000 (EUR)/year. Besides, an analysis of the O&M power plant reports was performed and compared to the best global practices. It was assessed that the tracker systems’ major issues are the forerunner of the most significant PV power plant underperformance. In addition, issues in inverters and combiner boxes were also reported, leading to internal shutdowns. In this case, predictive maintenance and automated plant diagnosis with a bottom-up approach using low-cost data acquisition and processing systems, starting from the strings level, were recommended.
Hamid Iftikhar; Eduardo Sarquis; P. Branco. Why Can Simple Operation and Maintenance (O&M) Practices in Large-Scale Grid-Connected PV Power Plants Play a Key Role in Improving Its Energy Output? Energies 2021, 14, 3798 .
AMA StyleHamid Iftikhar, Eduardo Sarquis, P. Branco. Why Can Simple Operation and Maintenance (O&M) Practices in Large-Scale Grid-Connected PV Power Plants Play a Key Role in Improving Its Energy Output? Energies. 2021; 14 (13):3798.
Chicago/Turabian StyleHamid Iftikhar; Eduardo Sarquis; P. Branco. 2021. "Why Can Simple Operation and Maintenance (O&M) Practices in Large-Scale Grid-Connected PV Power Plants Play a Key Role in Improving Its Energy Output?" Energies 14, no. 13: 3798.
Sustainability and efficiency in irrigation are essential in the management of the water–energy–food nexus to reach the Sustainable Development Goals in 2030. In irrigation systems, the reduction of energy consumption is required to improve the system efficiency and consequently the sustainability indicators of the water network. The use of pumps working as turbines (PATs) has been a feasible solution to recover the excess of energy where pressure reduction valves are installed. This research demonstrates the use of PATs under steady and unsteady conditions by analyzing the application in a real irrigation networks located in Vallada (Valencia, Spain). The study shows the possibility of recovering 44 MWh/year using PATs installed upstream of the irrigation hydrants. The real behavior of the PAT operation in a stand-alone recovery energy solution allowed analysis of the flow, head and efficiency variation as a function of the rotational speed, as well as the minimum capacitance to self-excite the generator and the resistive load of the electrical circuit. The PAT limit is examined in terms of the overpressure induced by a fast closure manoeuvre of hydrants, and the runaway conditions due to the disconnection from the electrical load.
Modesto Pérez-Sánchez; João Fernandes; P. Branco; P. López-Jiménez; Helena Ramos. PATs Behavior in Pressurized Irrigation Hydrants towards Sustainability. Water 2021, 13, 1359 .
AMA StyleModesto Pérez-Sánchez, João Fernandes, P. Branco, P. López-Jiménez, Helena Ramos. PATs Behavior in Pressurized Irrigation Hydrants towards Sustainability. Water. 2021; 13 (10):1359.
Chicago/Turabian StyleModesto Pérez-Sánchez; João Fernandes; P. Branco; P. López-Jiménez; Helena Ramos. 2021. "PATs Behavior in Pressurized Irrigation Hydrants towards Sustainability." Water 13, no. 10: 1359.
Electromagnetic heating of high-temperature superconductors (HTSs) and non-perfect thermal insulation of cryostats cause liquid nitrogen (LN2) vaporization and consumption. This paper presents results from the thermo-hydraulic analysis of the maximum safety service time of the prototype of a horizontal axis radial levitation bearing with zero-field cooled (ZFC) HTS bulks. It first studies the temperature sensitivity of yttrium barium copper oxide (YBCO) bulks to the LN2 level, particularly when partially immersed. This, when the main component of heat flux is according to the c-axis of the bulk crystal structure, that is the case of the studied bearing prototype and in most of all cryostats of maglev vehicles. Measurements used two platinum resistance thermometers leaning the top and side surfaces of a non-magnetized ZFC YBCO bulk. Correlations between the temperatures measured by the two platinum resistors are made to determine the average temperature of YBCO bulk. The thermal-time constant associated with a YBCO bulk losing contact with LN2 is also determined for two conditions: 1) initial ZFC and 2) initial field-cooled (FC) under the influence of typical magnetic field values generated by the studied bearing permanent magnet (PM) rotor. Results indicate that the YBCO temperature evolution is not notably affected by Joule losses from initial magnetization currents for this bearing. Due to continuous PM rings, the magnetic field perceived by the YBCO bulks does not change in the ideal case of spinning with no vibrations. Another experiment shows that the heating by induction from vibration dynamics does not contribute notably to LN2 consumption. Finally, the safety service time is verified from measured LN2 mass and level evolution in the HTS bearing's stator, due mainly to defective thermal insulation from the room temperature. The process consisted of calculating the times that different leveled YBCO bulks experiments reached the critical temperature and using the conclusions taken from the initial study about the temperature sensitivity of single bulks to the LN2 level. 3D finite element simulations reinforce our experimental results.
Antonio J. Costa Arsenio; Paulo J. Costa Branco. Thermo-Hydraulic Analysis of a Horizontal HTS ZFC Levitating Bearing Concerning Its Autonomy Safety Service Time. IEEE Transactions on Applied Superconductivity 2021, 31, 1 -10.
AMA StyleAntonio J. Costa Arsenio, Paulo J. Costa Branco. Thermo-Hydraulic Analysis of a Horizontal HTS ZFC Levitating Bearing Concerning Its Autonomy Safety Service Time. IEEE Transactions on Applied Superconductivity. 2021; 31 (5):1-10.
Chicago/Turabian StyleAntonio J. Costa Arsenio; Paulo J. Costa Branco. 2021. "Thermo-Hydraulic Analysis of a Horizontal HTS ZFC Levitating Bearing Concerning Its Autonomy Safety Service Time." IEEE Transactions on Applied Superconductivity 31, no. 5: 1-10.
Requalification of low-head ramped weirs through the addition of substrates (retrofitting) has attracted attention in recent years. However, few studies are available on how this measure affects the negotiation of ramped weirs by fish. This study aimed to assess the performance of an experimental ramped weir (3.00 m long with 10% slope; 0.30 m head-drop) to enhance the passage of a potamodromous cyprinid species, the Iberian barbel (Luciobarbus bocagei). Attention was given to testing the effects of the addition of a substrate, in this case cobbles, to the ramp (Nature) vs. a smooth bottom (Control), and discharge (Q; 55 L·s−1 and 110 L·s−1 (or specific discharge per unit width, q = 92 L·s−1·m−1 and 183 L·s−1·m−1)) on fish passage performance. Fish physiological responses to stress and fatigue, measured by glucose and lactate concentrations in blood samples, were also analysed. Results showed that the Nature design generally increased fish movements and successful upstream passages, and enhanced fish passage performance by enabling faster negotiations. Fish movements were also affected by increasing discharge, registering reductions with 110 L·s−1. Results of the physiological parameters indicate that both glucose and lactate concentrations were also influenced by discharge. The outcomes from this study present important information about fish passage performance across low-head ramped weirs and could provide data needed to help biologists and engineers to develop more effective structures to alleviate small instream obstacles.
Susana Amaral; Paulo Branco; Filipe Romão; Maria Ferreira; António Pinheiro; José Santos. Evaluation of Low-Head Ramped Weirs for a Potamodromous Cyprinid: Effects of Substrate Addition and Discharge on Fish Passage Performance, Stress and Fatigue. Water 2021, 13, 765 .
AMA StyleSusana Amaral, Paulo Branco, Filipe Romão, Maria Ferreira, António Pinheiro, José Santos. Evaluation of Low-Head Ramped Weirs for a Potamodromous Cyprinid: Effects of Substrate Addition and Discharge on Fish Passage Performance, Stress and Fatigue. Water. 2021; 13 (6):765.
Chicago/Turabian StyleSusana Amaral; Paulo Branco; Filipe Romão; Maria Ferreira; António Pinheiro; José Santos. 2021. "Evaluation of Low-Head Ramped Weirs for a Potamodromous Cyprinid: Effects of Substrate Addition and Discharge on Fish Passage Performance, Stress and Fatigue." Water 13, no. 6: 765.
This paper proposes a novel methodology for calculating a space-varying permeability in HTS bulks, ensuring the same magnetic energy stored in E-J models at each infinitesimal volume. This stationary model is applied for the electromagnetic force calculation in HTS bulks. For the design of HTS bulk machines, multi-objective optimization is necessary to have accurate results. However, due to the nonlinear nature of HTS bulks finite element, Finite Element Analysis (FEA) simulations for optimization are heavily time consuming, even using 2D models, making this approach “infeasible.” The use of equivalent models that guarantee precise results with shorter computation times is then imperative. The method proposed is applied following two basic steps. First, the 3D finite element model is simulated without the bulk to obtain the spatial magnetic flux distribution in the volume where it should be. In the second step, the bulk is included, and the HTS magnetic flux density distribution is obtained using superconducting physics. From these, the HTS equivalent space-varying permeability is computed by the quotient of the two magnetic flux densities. With this, stationary and linear FEA simulations can now be easily performed for the computation of electromagnetic forces in design problems. The proposed method was validated using simulation and experimental tests based on YBCO/GdBCO permanent-magnet force interactions. These results show that, with a previous general study of the geometry to optimize, the equivalent model can be used for optimization purposes, greatly reducing the computational time.
Ines S. P. Peixoto; F. Ferreira da Silva; Joao F. P. Fernandes; P. J. Da Costa Branco. 3D Equivalent Space-Varying Permeability Model of HTS Bulks for Computation of Electromagnetic Forces. IEEE Transactions on Applied Superconductivity 2021, 31, 1 -7.
AMA StyleInes S. P. Peixoto, F. Ferreira da Silva, Joao F. P. Fernandes, P. J. Da Costa Branco. 3D Equivalent Space-Varying Permeability Model of HTS Bulks for Computation of Electromagnetic Forces. IEEE Transactions on Applied Superconductivity. 2021; 31 (5):1-7.
Chicago/Turabian StyleInes S. P. Peixoto; F. Ferreira da Silva; Joao F. P. Fernandes; P. J. Da Costa Branco. 2021. "3D Equivalent Space-Varying Permeability Model of HTS Bulks for Computation of Electromagnetic Forces." IEEE Transactions on Applied Superconductivity 31, no. 5: 1-7.
This work focuses on implementing HTS bulks in the excitation circuit of low-speed synchronous generators as permanent mag-nets. In addition to the implementation study, it is also addressed to remagnetize HTS bulks in electric generators. To reduce the maintenance costs and time required for the magnetization pro-cess, an in-loco remagnetization is used. The HTS bulks are magnetized in their position inside the machine's magnetic cir-cuit. A pulse-field magnetization (PFM) technique is used, using the stator coils of a linear generator. YBCO and GdBCO sam-ples are tested. The experimental procedure starts with the in-loco PFM to magnetize the HTS bulks and, by applying an oscil-latory movement to the linear generator's moving part, measur-ing the magnetic flux density induced voltage is done. Experi-mental tests show that, for the FeSi core used in the generator, the YBCO material is most suitable for the excitation circuit.
Joao Arnaud; Joao F. P. Fernandes; Paulo J. Costa Branco. Use of Bulk Superconductors in the Excitation System of Low-Speed Synchronous Generators. IEEE Transactions on Applied Superconductivity 2021, 31, 1 -6.
AMA StyleJoao Arnaud, Joao F. P. Fernandes, Paulo J. Costa Branco. Use of Bulk Superconductors in the Excitation System of Low-Speed Synchronous Generators. IEEE Transactions on Applied Superconductivity. 2021; 31 (5):1-6.
Chicago/Turabian StyleJoao Arnaud; Joao F. P. Fernandes; Paulo J. Costa Branco. 2021. "Use of Bulk Superconductors in the Excitation System of Low-Speed Synchronous Generators." IEEE Transactions on Applied Superconductivity 31, no. 5: 1-6.
Pool-type fishways have been increasingly tested to improve fish passage performance and minimize migration delays. Designing cost-effective fishways is essential for a trade-off between water uses and successful longitudinal connectivity restoration. The multislot fishway (MSF) concept, which operates with 30–50% lower discharge than a vertical slot fishway (VSF), was recently developed. This study assessed and compared the entrance performance (entrance time; entry efficiency) and transit times of two cyprinids for VSFs and MSFs. Four configurations, with the same structural characteristics (slope; water depth; head drop; pool width and depth), operating with different discharges (Q), were tested (VSF 1: Q = 112 L·s−1; VSF 2: Q = 80 L·s−1; MSF 1: Q = 58 L·s−1; MSF 2: Q = 37 L·s−1). Hydrodynamics characterization was performed using a numerical model. Results showed that entry efficiency was higher in MSFs than in VSFs, while entrance time and transit time were overall lower. Numerical modelling revealed that velocities were around 30% lower in MSFs, and turbulence could reach a difference of around 70% in Reynolds shear stress and 50% in turbulent kinetic energy. Overall, MSFs can be considered as a cost-effective fishway solution that can balance the trade-offs between divergent interests in water uses.
Filipe Romão; Ana L. Quaresma; José M. Santos; Susana D. Amaral; Paulo Branco; António N. Pinheiro. Multislot Fishway Improves Entrance Performance and Fish Transit Time over Vertical Slots. Water 2021, 13, 275 .
AMA StyleFilipe Romão, Ana L. Quaresma, José M. Santos, Susana D. Amaral, Paulo Branco, António N. Pinheiro. Multislot Fishway Improves Entrance Performance and Fish Transit Time over Vertical Slots. Water. 2021; 13 (3):275.
Chicago/Turabian StyleFilipe Romão; Ana L. Quaresma; José M. Santos; Susana D. Amaral; Paulo Branco; António N. Pinheiro. 2021. "Multislot Fishway Improves Entrance Performance and Fish Transit Time over Vertical Slots." Water 13, no. 3: 275.
The mismatch is a phenomenon intrinsically related to photovoltaic (PV) arrays, either because they are eventually subject to non-uniform irradiance and temperature conditions, or because of inner variations on the components, ageing or occurrence of failures. Despite mismatch losses being so present in the life of a PV system, the available tools for the study of PV arrays response through simulation today present limitations for the handling of mismatch conditions. Most of them do not support non-uniform conditions, and the ones that do, solely explore irradiance and temperature variations, ignoring other causes for mismatches, such as defects on PV cells. This paper proposes a simulation framework that allows manipulation of each parameter in each cell individually to reproduce mismatch conditions, including failures. Each PV cell is represented by the one diode equivalent circuit model, for which two different parameterisation methods were tested: California Energy Commission (CEC) and PVSyst. The proposed simulation framework was validated with laboratory measurements of a PV module under 15 different mismatch conditions of partial shading and failure (short circuit). The results showed a consistent similarity between calculated and measured I–V curves, and errors at the curves’ maximum power points stayed within the instruments’ accuracy range, roughly 1.0 V and 0.2 A. The proposed simulation framework brings great flexibility to the studies of mismatch through simulation, allowing the calculation of the I–V curve of PV strings and small arrays subjected to mismatch conditions due to non-uniform irradiance and temperature profiles, but most significantly failures in the cells.
Eduardo Abdon Sarquis Filho; Carlos Alberto Ferreira Fernandes; Paulo José Da Costa Branco. A complete framework for the simulation of photovoltaic arrays under mismatch conditions. Solar Energy 2020, 213, 13 -26.
AMA StyleEduardo Abdon Sarquis Filho, Carlos Alberto Ferreira Fernandes, Paulo José Da Costa Branco. A complete framework for the simulation of photovoltaic arrays under mismatch conditions. Solar Energy. 2020; 213 ():13-26.
Chicago/Turabian StyleEduardo Abdon Sarquis Filho; Carlos Alberto Ferreira Fernandes; Paulo José Da Costa Branco. 2020. "A complete framework for the simulation of photovoltaic arrays under mismatch conditions." Solar Energy 213, no. : 13-26.
River longitudinal connectivity is crucial for diadromous fish species to reproduce and grow, its fragmentation by large dams may prevent these species to complete their life cycle. This work aims to evaluate the impact of large dams on the structural longitudinal connectivity at the European scale, from a Diadromous fish species perspective, since the beginning of the 20th century until the early 21st century. Based on large dam locations and completion year, a multitude of river impairment metrics were calculated at three spatial scales for six European oceanic regions and 12 time periods. The number of basins affected by large dams is overall low (0.4%), but for large river basins, that cover 78% of Europe's area, 69.5% of all basins, 55.4% of the sub-basins and 68.4% of river length are impaired. River network connectivity impairment became increasingly significant during the second half of the 20th century and is nowadays spatially widespread across Europe. Except for the North Atlantic, all oceanic regions have over 50% of impacted river length. Considering large river basins, the Mediterranean (95.2%) and West Atlantic (84.6%) regions are the most affected, while the Black (92.1%) and Caspian (96.0%) regions stand out as those with most compromised river length. In 60 years, Europe has gone from reduced impairment to over two-thirds of its large rivers with structural connectivity problems due to large dams. The number of such barriers increased significantly in the second half of the 20th century, especially main stem dams with decreasing distance to the river mouth. Currently, the structural longitudinal connectivity of European river networks is severely impacted. This concerns all regions considered, and those in southern Europe will face even higher challenges, given that this will be a future hot spot for hydropower development and predictably more affected by climate change.
Gonçalo Duarte; Pedro Segurado; Gertrud Haidvogl; Didier Pont; Maria Teresa Ferreira; Paulo Branco. Damn those damn dams: Fluvial longitudinal connectivity impairment for European diadromous fish throughout the 20th century. Science of The Total Environment 2020, 761, 143293 .
AMA StyleGonçalo Duarte, Pedro Segurado, Gertrud Haidvogl, Didier Pont, Maria Teresa Ferreira, Paulo Branco. Damn those damn dams: Fluvial longitudinal connectivity impairment for European diadromous fish throughout the 20th century. Science of The Total Environment. 2020; 761 ():143293.
Chicago/Turabian StyleGonçalo Duarte; Pedro Segurado; Gertrud Haidvogl; Didier Pont; Maria Teresa Ferreira; Paulo Branco. 2020. "Damn those damn dams: Fluvial longitudinal connectivity impairment for European diadromous fish throughout the 20th century." Science of The Total Environment 761, no. : 143293.
This study describes an integrated modelling approach to better understand the trophic status of the Montargil reservoir (southern Portugal) under climate change scenarios. The SWAT and CE-QUAL-W2 models were applied to the basin and reservoir, respectively, for simulating water and nutrient dynamics while considering one climatic scenario and two decadal timelines (2025–2034 and 2055–2064). Model simulations showed that the dissolved oxygen concentration in the reservoir's hypolimnion is expected to decrease by 60% in both decadal timelines, while the chlorophyll-a concentration in the reservoir's epiliminion is expected to increase by 25%. The total phosphorus concentration (TP) is predicted to increase in the water column surface by 63% and in the hypolimion by 90% during the 2030 timeline. These results are even more severe during the 2060 timeline. Under this climate change scenario, the reservoir showed a eutrophic state during 70–80% of both timelines. Even considering measures that involve decreases in 30 to 35% of water use, the eutrophic state is not expected to improve.
Carina Almeida; Paulo Branco; Pedro Segurado; Tiago B. Ramos; Teresa Ferreira; Ramiro Neves; Rodrigo Proença de Oliveira. Evaluation of the trophic status in a Mediterranean reservoir under climate change: An integrated modelling approach. Journal of Water and Climate Change 2020, 12, 817 -832.
AMA StyleCarina Almeida, Paulo Branco, Pedro Segurado, Tiago B. Ramos, Teresa Ferreira, Ramiro Neves, Rodrigo Proença de Oliveira. Evaluation of the trophic status in a Mediterranean reservoir under climate change: An integrated modelling approach. Journal of Water and Climate Change. 2020; 12 (3):817-832.
Chicago/Turabian StyleCarina Almeida; Paulo Branco; Pedro Segurado; Tiago B. Ramos; Teresa Ferreira; Ramiro Neves; Rodrigo Proença de Oliveira. 2020. "Evaluation of the trophic status in a Mediterranean reservoir under climate change: An integrated modelling approach." Journal of Water and Climate Change 12, no. 3: 817-832.
The use of pumps working as turbines (PATs) is a sustainable technical measure that contributes to the improvement of energy efficiency in water systems. However, its performance analysis in off-grid recovery systems is a complex task that must consider both hydraulic (PAT) and electrical machines (typically a self-excited induction generator-SEIG). Aside from several kinds of research that analyze the PAT-SEIG behavior under steady-state constant hydraulic and electrical conditions, this research focuses on the analysis of PAT-SEIG transient regimes, by analyzing their variation when a sudden change occurs in the hydraulic or electrical components. Analytical models were developed to represent the operation of SEIG, PAT, and the PAT-SEIG coupled system. Hydraulic and electromechanical experimental tests validated these models. An excellent fit was obtained when analytical and experimental values were compared. With these models, the impact on the operation of the PAT-SEIG system was examined when sudden change occurred in the excitation capacitances, resistive loads, or recovered head. With a sudden increase of resistive load, the hydraulic power and SEIG stator current remain almost constant. However, there is an increase of SEIG reactive power, decreasing the PAT-SEIG efficiency. Also, with a sudden increase of SEIG capacitors or PAT hydraulic head, the SEIG stator current increases once and not again, while PAT-SEIG efficiency decreases, but the induction generator can be overloaded. The development of this research is key to the advancement of future models which can analyze the coupling of micro-hydropower solutions.
Filipe C. Madeira; João F. P. Fernandes; Modesto Pérez-Sánchez; P. Amparo López-Jiménez; Helena M. Ramos; P. J. Costa Branco. Electro-Hydraulic Transient Regimes in Isolated Pumps Working as Turbines with Self-Excited Induction Generators. Energies 2020, 13, 4521 .
AMA StyleFilipe C. Madeira, João F. P. Fernandes, Modesto Pérez-Sánchez, P. Amparo López-Jiménez, Helena M. Ramos, P. J. Costa Branco. Electro-Hydraulic Transient Regimes in Isolated Pumps Working as Turbines with Self-Excited Induction Generators. Energies. 2020; 13 (17):4521.
Chicago/Turabian StyleFilipe C. Madeira; João F. P. Fernandes; Modesto Pérez-Sánchez; P. Amparo López-Jiménez; Helena M. Ramos; P. J. Costa Branco. 2020. "Electro-Hydraulic Transient Regimes in Isolated Pumps Working as Turbines with Self-Excited Induction Generators." Energies 13, no. 17: 4521.
Climate and land-use change drive a suite of stressors that shape ecosystems and interact to yield complex ecological responses (that is, additive, antagonistic and synergistic effects). We know little about the spatial scales relevant for the outcomes of such interactions and little about effect sizes. These knowledge gaps need to be filled to underpin future land management decisions or climate mitigation interventions for protecting and restoring freshwater ecosystems. This study combines data across scales from 33 mesocosm experiments with those from 14 river basins and 22 cross-basin studies in Europe, producing 174 combinations of paired-stressor effects on a biological response variable. Generalized linear models showed that only one of the two stressors had a significant effect in 39% of the analysed cases, 28% of the paired-stressor combinations resulted in additive effects and 33% resulted in interactive (antagonistic, synergistic, opposing or reversal) effects. For lakes, the frequencies of additive and interactive effects were similar for all spatial scales addressed, while for rivers these frequencies increased with scale. Nutrient enrichment was the overriding stressor for lakes, with effects generally exceeding those of secondary stressors. For rivers, the effects of nutrient enrichment were dependent on the specific stressor combination and biological response variable. These results vindicate the traditional focus of lake restoration and management on nutrient stress, while highlighting that river management requires more bespoke management solutions.
Sebastian Birk; Daniel Chapman; Laurence Carvalho; Bryan M. Spears; Hans Estrup Andersen; Christine Argillier; Stefan Auer; Annette Baattrup-Pedersen; Lindsay Banin; Meryem Beklioğlu; Elisabeth Bondar-Kunze; Angel Borja; Paulo Branco; Tuba Bucak; Anthonie D. Buijse; Ana Cristina Cardoso; Raoul-Marie Couture; Fabien Cremona; Dick De Zwart; Christian K. Feld; M. Teresa Ferreira; Heidrun Feuchtmayr; Mark O. Gessner; Alexander Gieswein; Lidija Globevnik; Daniel Graeber; Wolfram Graf; Cayetano Gutiérrez-Cánovas; Jenica Hanganu; Uğur Işkın; Marko Järvinen; Erik Jeppesen; Niina Kotamäki; Marijn Kuijper; Jan U. Lemm; Shenglan Lu; Anne Lyche Solheim; Ute Mischke; S. Jannicke Moe; Peeter Nõges; Tiina Nõges; Steve J. Ormerod; Yiannis Panagopoulos; Geoff Phillips; Leo Posthuma; Sarai Pouso; Christel Prudhomme; Katri Rankinen; Jes J. Rasmussen; Jessica Richardson; Alban Sagouis; José Maria Santos; Ralf B. Schäfer; Rafaela Schinegger; Stefan Schmutz; Susanne C. Schneider; Lisa Schülting; Pedro Segurado; Kostas Stefanidis; Bernd Sures; Stephen J. Thackeray; Jarno Turunen; María C. Uyarra; Markus Venohr; Peter Carsten Von Der Ohe; Nigel Willby; Daniel Hering. Impacts of multiple stressors on freshwater biota across spatial scales and ecosystems. Nature Ecology & Evolution 2020, 4, 1060 -1068.
AMA StyleSebastian Birk, Daniel Chapman, Laurence Carvalho, Bryan M. Spears, Hans Estrup Andersen, Christine Argillier, Stefan Auer, Annette Baattrup-Pedersen, Lindsay Banin, Meryem Beklioğlu, Elisabeth Bondar-Kunze, Angel Borja, Paulo Branco, Tuba Bucak, Anthonie D. Buijse, Ana Cristina Cardoso, Raoul-Marie Couture, Fabien Cremona, Dick De Zwart, Christian K. Feld, M. Teresa Ferreira, Heidrun Feuchtmayr, Mark O. Gessner, Alexander Gieswein, Lidija Globevnik, Daniel Graeber, Wolfram Graf, Cayetano Gutiérrez-Cánovas, Jenica Hanganu, Uğur Işkın, Marko Järvinen, Erik Jeppesen, Niina Kotamäki, Marijn Kuijper, Jan U. Lemm, Shenglan Lu, Anne Lyche Solheim, Ute Mischke, S. Jannicke Moe, Peeter Nõges, Tiina Nõges, Steve J. Ormerod, Yiannis Panagopoulos, Geoff Phillips, Leo Posthuma, Sarai Pouso, Christel Prudhomme, Katri Rankinen, Jes J. Rasmussen, Jessica Richardson, Alban Sagouis, José Maria Santos, Ralf B. Schäfer, Rafaela Schinegger, Stefan Schmutz, Susanne C. Schneider, Lisa Schülting, Pedro Segurado, Kostas Stefanidis, Bernd Sures, Stephen J. Thackeray, Jarno Turunen, María C. Uyarra, Markus Venohr, Peter Carsten Von Der Ohe, Nigel Willby, Daniel Hering. Impacts of multiple stressors on freshwater biota across spatial scales and ecosystems. Nature Ecology & Evolution. 2020; 4 (8):1060-1068.
Chicago/Turabian StyleSebastian Birk; Daniel Chapman; Laurence Carvalho; Bryan M. Spears; Hans Estrup Andersen; Christine Argillier; Stefan Auer; Annette Baattrup-Pedersen; Lindsay Banin; Meryem Beklioğlu; Elisabeth Bondar-Kunze; Angel Borja; Paulo Branco; Tuba Bucak; Anthonie D. Buijse; Ana Cristina Cardoso; Raoul-Marie Couture; Fabien Cremona; Dick De Zwart; Christian K. Feld; M. Teresa Ferreira; Heidrun Feuchtmayr; Mark O. Gessner; Alexander Gieswein; Lidija Globevnik; Daniel Graeber; Wolfram Graf; Cayetano Gutiérrez-Cánovas; Jenica Hanganu; Uğur Işkın; Marko Järvinen; Erik Jeppesen; Niina Kotamäki; Marijn Kuijper; Jan U. Lemm; Shenglan Lu; Anne Lyche Solheim; Ute Mischke; S. Jannicke Moe; Peeter Nõges; Tiina Nõges; Steve J. Ormerod; Yiannis Panagopoulos; Geoff Phillips; Leo Posthuma; Sarai Pouso; Christel Prudhomme; Katri Rankinen; Jes J. Rasmussen; Jessica Richardson; Alban Sagouis; José Maria Santos; Ralf B. Schäfer; Rafaela Schinegger; Stefan Schmutz; Susanne C. Schneider; Lisa Schülting; Pedro Segurado; Kostas Stefanidis; Bernd Sures; Stephen J. Thackeray; Jarno Turunen; María C. Uyarra; Markus Venohr; Peter Carsten Von Der Ohe; Nigel Willby; Daniel Hering. 2020. "Impacts of multiple stressors on freshwater biota across spatial scales and ecosystems." Nature Ecology & Evolution 4, no. 8: 1060-1068.
A high-performance 20 kW, 20 Nm, 8000 rpm, spoke-type interior permanent magnet motor to be integrated into a FormulaStudent electric car’s powertrain has been designed to meet demanding performance requirements for its driving cycle. This paper describes key steps in the design optimization, analysis, fabrication, and testing of this machine. Design optimization used the non-dominated sorting genetic algorithm II (NSGA-II) coupled with a hybrid analytical/finite element model to reduce the computational time, achieving a torque and efficiency of 20 Nm and 98.6%, respectively. A prototype has been constructed. The final motor design has been tested, where experimental nominal torque and efficiency have reached 18.2 Nm and 90%, respectively. Design challenges regarding the manufacturing are presented, justified, and discussed in detail. Test results were conducted to evaluate reliability and motor temperatures with and without water refrigeration at nominal current. Despite those adjustments in the optimized design, one shows that the impact on the car’s lap time was low, going from 77.3 s for the ideal optimized motor to 78.9 s for the prototyped motor.
Pedro P. C. Bhagubai; João G. Sarrico; João F. P. Fernandes; P. J. Costa Branco. Design, Multi-Objective Optimization, and Prototyping of a 20 kW 8000 rpm Permanent Magnet Synchronous Motor for a Competition Electric Vehicle. Energies 2020, 13, 2465 .
AMA StylePedro P. C. Bhagubai, João G. Sarrico, João F. P. Fernandes, P. J. Costa Branco. Design, Multi-Objective Optimization, and Prototyping of a 20 kW 8000 rpm Permanent Magnet Synchronous Motor for a Competition Electric Vehicle. Energies. 2020; 13 (10):2465.
Chicago/Turabian StylePedro P. C. Bhagubai; João G. Sarrico; João F. P. Fernandes; P. J. Costa Branco. 2020. "Design, Multi-Objective Optimization, and Prototyping of a 20 kW 8000 rpm Permanent Magnet Synchronous Motor for a Competition Electric Vehicle." Energies 13, no. 10: 2465.
Heatwaves, which can be defined as increases of at least 5 °C in air temperature for more than five consecutive days for a specified reference period, are expected to become more frequent under the ongoing climate change, with freshwater organisms being particularly vulnerable to high temperature fluctuations. In Mediterranean-climate areas, depending on the extent of summer droughts and loss of longitudinal connectivity, river segments may become isolated, maintaining fish populations confined to a series of disconnected pools, with no possibility to move to thermal refugia and thus becoming more prone to thermal stress. In this study, we evaluated the effect of a simulated heatwave on the swimming behaviour of juvenile stages of a potamodromous native cyprinid fish, the Iberian barbel Luciobarbus bocagei, under experimental mesocosm conditions. Behavioural traits included fish activity, boldness and shoal cohesion and were continuously measured at a constant flow velocity of 18 cm s−1, which is typical of riffle habitats. Overall, results show that the behaviour of juvenile Iberian barbel is likely to be affected by heatwaves, with fish displaying lower activity and boldness, while no clear difference was observed in shoal cohesion. This study highlights the importance of managing thermal refugia that are crucial for fish to persist in intermittent rivers. Future studies should focus on the interaction of heatwaves with other stressors, such as oxygen depletion, for a broader understanding of the perturbation affecting freshwater fishes under a changing climate.
Daniel Mameri; Paulo Branco; Maria Teresa Ferreira; José Maria Santos. Heatwave effects on the swimming behaviour of a Mediterranean freshwater fish, the Iberian barbel Luciobarbus bocagei. Science of The Total Environment 2020, 730, 139152 .
AMA StyleDaniel Mameri, Paulo Branco, Maria Teresa Ferreira, José Maria Santos. Heatwave effects on the swimming behaviour of a Mediterranean freshwater fish, the Iberian barbel Luciobarbus bocagei. Science of The Total Environment. 2020; 730 ():139152.
Chicago/Turabian StyleDaniel Mameri; Paulo Branco; Maria Teresa Ferreira; José Maria Santos. 2020. "Heatwave effects on the swimming behaviour of a Mediterranean freshwater fish, the Iberian barbel Luciobarbus bocagei." Science of The Total Environment 730, no. : 139152.
Reliability assessment in traditional power distribution systems has played a key role in power system planning, design, and operation. Recently, new information and communication technologies have been introduced in power systems automation and asset management, making the distribution network even more complex. In order to achieve efficient energy management, the distribution grid has to adopt a new configuration and operational conditions that are changing the paradigm of the actual electrical system. Therefore, the emergence of the cyber-physical systems concept to face future energetic needs requires alternative approaches for evaluating the reliability of modern distribution systems, especially in the smart grids environment. In this paper, a reliability approach that makes use of failure modes of power and cyber network main components is proposed to evaluate risk analysis in smart electrical distribution systems. We introduce the application of Failure Modes and Effects Analysis (FMEA) method in future smart grid systems in order to establish the impact of different failure modes on their performance. A smart grid test system is defined and failure modes and their effects for both power and the cyber components are presented. Preventive maintenance tasks are proposed and systematized to minimize the impact of high-risk failures and increase reliability.
Andrés A. Zúñiga; Alexandre Baleia; João Fernandes; Paulo Jose Da Costa Branco. Classical Failure Modes and Effects Analysis in the Context of Smart Grid Cyber-Physical Systems. Energies 2020, 13, 1215 .
AMA StyleAndrés A. Zúñiga, Alexandre Baleia, João Fernandes, Paulo Jose Da Costa Branco. Classical Failure Modes and Effects Analysis in the Context of Smart Grid Cyber-Physical Systems. Energies. 2020; 13 (5):1215.
Chicago/Turabian StyleAndrés A. Zúñiga; Alexandre Baleia; João Fernandes; Paulo Jose Da Costa Branco. 2020. "Classical Failure Modes and Effects Analysis in the Context of Smart Grid Cyber-Physical Systems." Energies 13, no. 5: 1215.
Reliability assessment in traditional power distribution systems has played a key role in power system planning, design, and operation. Recently, new information and communication technologies have been introduced in power systems automation and asset management, making the distribution network even more complex. In order to achieve efficient energy management, the distribution grid has to adopt a new configuration and operational conditions that are changing the paradigm of the actual electrical system. Therefore, the emergence of the cyber-physical systems concept to face future energetic needs requires alternative approaches for evaluating the reliability of modern distribution systems, especially in the smart grids environment. In this paper, a reliability approach that makes use of failure modes of power and cyber network main components is proposed to evaluate risk analysis in smart electrical distribution systems. We introduce the application of Failure Modes and Effects Analysis (FMEA) method in future smart grid systems in order to establish the impact of different failure modes on their performance. A smart grid test system is defined and failure modes and their effects for both power and the cyber components are presented. Preventive maintenance tasks are proposed and systematized to minimize the impact of high-risk failures and increase reliability.
Andrés A. Zúñiga; Alexandre Baleia; João Fernandes; Paulo Jose Da Costa Branco. Classical Failure Modes and Effects Analysis in the Context of Smart Grid Cyber-Physical Systems. 2020, 1 .
AMA StyleAndrés A. Zúñiga, Alexandre Baleia, João Fernandes, Paulo Jose Da Costa Branco. Classical Failure Modes and Effects Analysis in the Context of Smart Grid Cyber-Physical Systems. . 2020; ():1.
Chicago/Turabian StyleAndrés A. Zúñiga; Alexandre Baleia; João Fernandes; Paulo Jose Da Costa Branco. 2020. "Classical Failure Modes and Effects Analysis in the Context of Smart Grid Cyber-Physical Systems." , no. : 1.
The majority of opportunities to energy savings today and in the next decades are in the existing building stock, including commercial and retail ones. These are constrained by old equipment, aging infrastructure, and inadequate operations resources. In particular, we focus on a retail store located in Lisbon, El Corte Inglés, to reduce its electricity consumption while maintaining the same level of service and continuing to be a profitable business. Improving the operation of the air-handling unit (AHU) and the operation schedule of floors illumination is our focus. Data provided had long-term records of variables as the building power consumption, exterior temperature, solar irradiation, elevators, and HVAC system. Two artificial neural networks (ANN) models were developed to predict the building power consumption and indoor average temperature, which allowed verifying the impact of small variations in the AHU electricity consumption. We deal both with the indoor average temperature (comfort) and power consumption of AHU to reduce the electric energy cost. The study leads to a decrease of 9.6% of the total electricity consumption, with an average indoor temperature increasing by only 0.15 °C. The total potential savings considering all the building 48 AHUs resulted in very good savings of 34,000 euros per year.
Eduardo R. G. Poço; João M. C. Sousa; P. J. Costa Branco. Improving the energy efficiency of aging retail buildings: a large department store in Lisbon as case study. Energy Systems 2020, 1 -31.
AMA StyleEduardo R. G. Poço, João M. C. Sousa, P. J. Costa Branco. Improving the energy efficiency of aging retail buildings: a large department store in Lisbon as case study. Energy Systems. 2020; ():1-31.
Chicago/Turabian StyleEduardo R. G. Poço; João M. C. Sousa; P. J. Costa Branco. 2020. "Improving the energy efficiency of aging retail buildings: a large department store in Lisbon as case study." Energy Systems , no. : 1-31.
Paulo Branco; J.A. Martin. Design of an Electro-Hydraulic System Using Neuro-Fuzzy Techniques. Fusion of Neural Networks, Fuzzy Systems, and Genetic Algorithms 2020, 67 -104.
AMA StylePaulo Branco, J.A. Martin. Design of an Electro-Hydraulic System Using Neuro-Fuzzy Techniques. Fusion of Neural Networks, Fuzzy Systems, and Genetic Algorithms. 2020; ():67-104.
Chicago/Turabian StylePaulo Branco; J.A. Martin. 2020. "Design of an Electro-Hydraulic System Using Neuro-Fuzzy Techniques." Fusion of Neural Networks, Fuzzy Systems, and Genetic Algorithms , no. : 67-104.
Freshwater systems have increasingly been subjected to a multitude of human pressures and the re-establishment of their ecological integrity is currently a major worldwide challenge. Expected future climate and socioeconomic changes will most probably further exacerbate such challenges. Modelling techniques may provide useful tools to help facing these demands, but their use is still limited within ecological quality assessment of water resources due to its technical complexity. We developed a Bayesian Belief Network (BBN) framework for modelling the ecological quality of rivers and streams in two European river basins located in two distinct European climatic regions: the Odense Fjord basin (Denmark) and the Sorraia basin (Portugal). This method enabled us to integrate different data sources into a single framework to model the effect of multiple stressors on several biological indicators of river water quality and, subsequently, on their ecological status. The BBN provided a simple interactive user interface with which we simulated combined climate and socioeconomic changes scenarios to assess their impacts on river ecological status. According to the resulting BBNs the scenarios demonstrated small impacts of climate and socioeconomic changes on the biological quality elements analysed. This yield a final ecological status similar to the baseline in the Odense case, and slightly worse in Sorraia. Since the present situation already depicts a high percentage of rivers and streams with moderate or worse ecological status in both basins, this means that many of them would not fulfil the Water Framework Directive target in the future. Results also showed that macrophytes and fish indices were mainly responsible for a non-desirable overall ecological status in Odense and Sorraia, respectively. The approach followed in this study is novel, since BBN modelling is used for the first time for assessing the ecological status of rivers and streams under future scenarios, using an ensemble of biological quality elements. An important advantage of this tool is that it may easily be updated with new knowledge on the nature of relationships already established in the BBN or even by introducing new causal links. By encompassing two case studies of very different characteristics, these BBN may be more easily adapted as decision-making tools for water management of other river basins.
Eugenio Molina-Navarro; Pedro Segurado; Paulo Branco; Carina Almeida; Hans Estrup Andersen. Predicting the ecological status of rivers and streams under different climatic and socioeconomic scenarios using Bayesian Belief Networks. Limnologica 2019, 80, 125742 .
AMA StyleEugenio Molina-Navarro, Pedro Segurado, Paulo Branco, Carina Almeida, Hans Estrup Andersen. Predicting the ecological status of rivers and streams under different climatic and socioeconomic scenarios using Bayesian Belief Networks. Limnologica. 2019; 80 ():125742.
Chicago/Turabian StyleEugenio Molina-Navarro; Pedro Segurado; Paulo Branco; Carina Almeida; Hans Estrup Andersen. 2019. "Predicting the ecological status of rivers and streams under different climatic and socioeconomic scenarios using Bayesian Belief Networks." Limnologica 80, no. : 125742.