ESTiG - Posters em Encontros Científicos Internacionais
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- Aerial sonic anemometry - preleminary resultsPublication . Marques, Filipe; Ribeiro, Luís Frölén; Meles, V.ASA (Aerial Sonic Anemometry) project intends to use sonic anemometers in airborne platforms, complementing meteorological masts measurements over mountainous terrain. The additional information will be inputted into CFD models to assess complex mean and turbulent flow fields over mountainous terrain for wind energy purposes. The kind of platform and its distortion over the sonic measuring volume was considered: sonic anemometer structure over the platform and its behavior, and sonic transducers location relatively to platform. These limitations conditioned the choice of model planes to units with central or rear plan propulsion. Due to the lack of commercial offer, this type of configuration combined with payload capacity, led our choice to the Hobbyking FPV 168 with a wingspan of 1660 mm, fuselage of 1190 mm and a payload capacity of 2.3 kg. To prevent the distortion on the measurement volume, the minimal distance from the sonic head to the plane model was set to be equal to the distance from the front to the wing’s leading edge. The concept of flying a model plane with a sonic anemometer installed on it was validated, and it was possible to fly the model hauling a proxy of a Young 81000 sonic anemometer with perfect flying control. Flying tests were made in order to establish the best configuration of the center of mass of whole setup: airframe, batteries and sonic proxy structure. An electrical engine was used for commodity. The plane equipped with a 10”x7” 3 bladed pusher propeller, and at maximum engine rotation and local atmospheric conditions the batteries yielded a maximum of 37 Ah for the whole electric system. The flight autonomy is estimated to be between 8 to 10 minutes depending on local winds (1 battery of 4 elements of 4.2 V and 3700mAh). Future steps of this project are the use of the present setup to explore GPS, autopilot and data acquisition features. The increase of flight autonomy with the sonic platform will require larger aircrafts that are undergoing a process of selection.
- Aerial sonic anemometry for wind resource assessmentPublication . Ribeiro, Luís Frölén; Marques, FilipeThis project intends to recur to sonic anemometers in a airborne platforms to get wind information over the flying area between met masts or waypoints. Multiple platforms measuring simultaneously to complement ground based measurements. The concept is being tested and preliminary results show that key issues are related to the positioning system – differential GPS and autopilot.
- Analyis of stresses in drilled composite materialsPublication . Fernandes, Maria; Natal, Renato; Fonseca, E.M.M.In medicine there are many surgical procedures that involve the bone tissue, often entail cutting, drilling or screwing operations of the bone. The success of these surgeries depends on many factors and the bone damage degree generated during the drilling. The cutting effort achieved during the drilling process is one of the problems and is directly related with the drilling parameters. It is essential to understand and to improve the cutting conditions to minimize the bone damage.
- Aplicação de SIG na localização de áreas para infiltração de águas residuais tratadas na sub-região das Beiras e Serra da EstrelaPublication . Silva, Flora; Albuquerque, António; Cavaleiro, VictorA escassez de água para consumo humano é considerada um problema que tem vindo a aumentar em todo o Mundo. A recarga artificial de aquíferos com águas residuais tratadas, pode contribuir para a reposição de volumes de água no solo, o que pode ser muito vantajoso em áreas com deficit hídrico ou com sobre-exploração de águas subterrâneas. O objetivo principal deste estudo centra-se na identificação de potenciais locais, na sub-região das Beiras e Serra da Estrela, para a infiltração de águas residuais tratadas provenientes da ETAR de Vila Fernando, um aglomerado urbano do distrito da Guarda, utilizando uma análise multicritério baseada em SIG.
- Asphalt pavement temperature predictionPublication . Minhoto, Manuel; Pais, Jorge; Pereira, Paulo A.A.A 3-D finite element model (FEM) was developed to calculate the lemperature of an asphtalt rubber pavement localed in the Northeast of Portugal. The goal of the case study presented in this paper is to show the good accuracy temperature prediction tha can be obtained with this model when compared with the field pavement thermal condition obtained during a year. lnput data to the model are the hourly values for solar radiation and temperature and the mean daily value of wind speed obtained from a meteorological station. The therminal response of a multilayered pavement structure is modelled using a FEM transient thermal analysis and each analysis was initiated with the full deph constant initial temperature abtained from field measurements. For each analysed day, the pavement temperature was measured at a new pavement section, located in IP4 main road, near Bragança, in the north of Portugal. At this location, seven thermocouples were installed in the asphalt rubber and conventional mix layer, at seven different depths. These paviment data was used to validate this simulation model, by comparing model calculated data with mesured pavement temperatures. As conclusion, the 3-D finite-element analysis proved to be an interesting tool to simulate the transient behavior of the asphalt pavements. The presented simulation model can predict the pavement temperature at diferrent levels of bitumious layers with good accuracy.
- Automatic cattle identification using graph matching based on local invariant featuresPublication . Monteiro, Fernando C.Cattle muzzle classification can be considered as a biometric identifier important to animal traceability systems to ensure the integrity of the food chain. This paper presents a muzzle-based classification system that combines local invariant features with graph matching. The proposed approach consists of three phases; namely feature extraction, graph matching, and matching refinement. The experimental results showed that our approach is superior than existing works as ours achieves an all correct identification for the tested images. In addition, the results proved that our proposed method achieved this high accuracy even if the testing images are rotated in various angles.
- Beef quality evaluation systemPublication . Teixeira, Cátia; Cadavez, Vasco; Monteiro, Fernando C.The accurate segmentation of beef-marbling images plays an important role in making the correct decision on beef-marbling score in an automatic beef quality grading system. The purpose of this study is to develop a new segmentation method to correctly separate the fat flecks from the muscle in the rib-eye region of beef images.
- Bidirectional vehicle-to-grid interface under a microgrid projectPublication . Leite, Vicente; Ferreira, Ângela P.; Batista, JoséIn the emergent deployment of smart grids, storage systems play an important role into assets utilization optimization, providing backup power and peak-shaving. This concept becomes more critical in the context of microgrids with a high penetration of renewable energy resources. Plug-in electric vehicles provide an enormous distributed storage capability, which favours the technical and economical exploitation of such systems. This paper presents a comprehensive implementation and control of a bidirectional power converter for vehicle-to-grid integration, based on a bidirectional DC/DC converter followed by a full bridge DC/AC converter.
- Bioacumulação de poluentes metálicos (CD2+) por briófitas aquáticas fontinalis antipyreticaPublication . Martins, Ramiro; Boaventura, RuiO objectivo deste trabalho é compreender em termos quantitativos e qualitativos a acumulação e libertação de Cd(II) em solução aquosa, por uma briófita aquática - Fontinalis antipyretica – na perspectiva duma aplicação, quer na biomonitorização de cursos de água, quer na descontaminação de efluentes industriais. A acumulação de cádmio e posterior eliminação pelo musgo foi estudada em laboratório expondo as plantas a diferentes concentrações de cádmio na gama, 0,5 – 2,5 mg l-1, durante um período de contaminação de 144 h, e depois a água isenta de metal durante um período de descontaminação de 192 h. Foi ajustado um modelo cinético de transferência de massa de primeira ordem aos dados experimentais.
- Biological and phytochemical evaluation of methanolic extracts from ennyroyal and lavender species of the portuguese floraPublication . Serrano, Carmo; Barros, Lillian; Soares, Andreia; Pereira, Carla; Dias, Maria Inês; Alves, Maria José; Lopes, Violeta R.; Barata, Ana Maria; Farinha, NoémiaMedicinal and aromatic plants represent a healthier alternative to synthetic phenolic compounds, with a positive impact on therapeutic, aromatic and dietetic or gastronomic purposes. The in vitro biological activities of the phenolic compounds are an important parameter to select the most promising extracts for use in industrial applications. Thus, this study aimed to evaluate the in vitro antioxidant, antibacterial and cytotoxicity properties of 17 pennyroyal (Mentha pulegium L.) and 18 lavender (Lavandula pedunculata L.) accessions from the Portuguese flora, conserved in the Portuguese Genebank (BPGV), in order to select the accessions with the highest yield and high content of active ingredients for use in the different industrial sectors.