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- Flow rate measurements under sluice gatesPublication . Silva, Carlos Otero; Rijo, ManuelSluice gates are commonly used in canals for control and measurement of the flow. The discharge under sluice gates can be determined through the energy-momentum method (EM), the orifice flow rate equations and the application of the.-theorem of the dimensional analysis. The different discharge methods available, for free and submerged hydraulic jump including the transition between flows, were compared with experimental data. The performance of the different calibration methods was analyzed. The test program was conducted in the laboratory flume and in the experimental irrigation canal of the University of vora, Portugal. The test program shows that the evaluation of the discharge under sluice gates for free and submerged flows and for the transition between both flows through the methods based in the EM were those who had better results. For the studied gates openings, the results also show that the methods that consider the division of the submerged flow in partial and totally submerged did not improve the discharge results. (C) 2017 American Society of Civil Engineers.
- Clinical audit and quality improvement of the imaging departmentsPublication . Almeida, Rui; Silva, Carlos Otero; Gama, Zenewton; Abrantes, AntónioDue to the nature of imaging departments, clinical audit, quality improvement and safety topics have specific components that are not observed in other services or departments, as they have the particularity of performing imaging procedures that involve the application of ionizing radiation, in most cases 1. Within the complexities of these procedures, the patient's inability to choose the best procedure stands out, leaving the healthcare professionals involved the responsibility to select the best patient-centred procedure, with the application of the most effective and efficient protocol depending on the patient clinical situation, based on the available evidence, and applying the lowest radiation dose possible. This poster intends to address a set of tools aiming to assess professional performance and encourage changes in the practices adopted, such as Clinical Audit, Evidence-based Practice and Guidelines, which can be integrated in a major concept of clinical governance as a system of measures and procedures to deliver the best care to the patient.
- Comparative dose measurements in dentomaxillofacial imaging procedures: are Barium and Bismuth shields useful for the protection of eyes and thyroid glands?Publication . Almeida, Rui; Abrantes, António; Silva, Carlos OteroDose measurements were performed at the eye lens and thyroid level using TLD dosimeters, in different configurations (with and without shields) and using standard protocols with different values of voltage (kV) and current-time product (mAs). A total of 103 exposures were performed on patients, 84 of them using a MSCT GE Lightspeed 16 equipment and the remaining 19 using a CBCT NewTom GiANO equipment. These exposures were subdivided into 22 smaller samples (19 samples with 5 exposures each, 1 sample with 4 exposures and 2 samples with 2 exposures each), in accordance with the protocols and configurations adopted. 54 were performed without the use of shields and the remaining 49 with the use of shields, namely, a bismuth shield for the thyroid, a barium shield for the eye lens and, also, a bismuth shield for the breast, which was tested only in the routine MSCT protocol.
- Análise de modelos de escoamento aplicados a águas superficiais e subterrâneasPublication . Silva, Carlos Otero; Monteiro, José PauloA maioria das tecnologias empregues para interpretar o funcionamento dos sistemas hidrológicos funciona ainda de forma relativamente compartimentada. Este tipo de abordagem coloca actualmente grandes obstáculos às necessidades de análise integrada do ramo terrestre do ciclo hidrológico, nomeadamente no que diz respeito às relações entre águas subterrâneas e superficiais. Actualmente pode considerar-se relativamente trivial o desenvolvimento de soluções numéricas para problemas como a simulação de rebaixamentos produzidos por captações de água subterrânea num aquífero ou a simulação de hidrogramas de cursos de água, como resposta a episódios de precipitação numa bacia hidrográfica. Pelo contrário, a análise conjunta destes fenómenos recorrendo a modelos de simulação, continua a ser um tipo de abordagem fortemente confinado a aplicações teóricas e académicas. Uma vez que na Universidade do Algarve existem competências, actualmente separadas em ambos os domínios referidos (simulação de águas de superfície e águas subterrâneas), pretende-se com o presente trabalho contribuir para a análise das metodologias mais actuais no campo da aplicação conjunta deste tipo de modelos. Deu-se prioridade às aplicações estudadas em que se recorre à discretização dos domínios de escoamento em elementos finitos, dada a grande flexibilidade desta metodologia para a implementação de modelos de parâmetros distribuídos. A metodologia de trabalho consistiu na análise técnico-científica dos conceitos necessários à análise integrada dos escoamentos subterrâneos e superficiais e ao teste de casos de estudo implementados para validação de diferentes simulações sintéticas. Os casos apresentados contribuíram para a familiarização, por parte do candidato com este tipo de metodologias e, por outro lado, o seu desenvolvimento, permitiu a criação de procedimentos para a futura integração da rede hidrográfica em modelos já desenvolvidos na Universidade do Algarve para sistemas aquíferos regionais. De entre os casos seleccionados apresenta-se o tratamento de: 1) rebaixamento produzido por uma captação num sistema aquífero; 2) propagação da recarga num aquífero com um curso de água e 3) simulação de um episódio de precipitação, que gera escoamento superficial e escoamento subterrâneo, de acordo com a fracção de recarga e de escoamento superficial gerados em função da capacidade de infiltração definida para o solo.
- GIS-based site selection for agricultural water reservoirs: a case study of São Brás de Alportel, PortugalPublication . Dziuba, Olga; Custódio, Cláudia; Silva, Carlos Otero; Granja Martins, Fernando Miguel; Lança, Rui; Maria Neto Paixão Vazquez Fernandez Martins, HelenaIn the São Brás de Alportel municipality, water scarcity poses a significant constraint on agricultural activities. This study utilises Remote Sensing (RS) and Geographical Information Systems (GISs) to identify existing irrigated areas, delineate catchment basins, and select the most suitable sites for the installation of new surface water reservoirs. First, the principal territorial components were characterised, including physical elements (climate, geology, soils, and hydrography) and anthropogenic infrastructure (road network and high-voltage power lines). Summer Sentinel-2 satellite imagery was then analysed to calculate the Normalised Difference Vegetation Index (NDVI), enabling the identification and classification of irrigated agricultural parcels. Flow directions and accumulations derived from Digital Elevation Models (DEMs) facilitated the characterisation of 38 micro-catchments and the extraction of 758 km of the drainage network. The siting criteria required a minimum setback of 100 m from roads and high-voltage lines, excluded farmland currently in use, and favoured mountainous areas with low permeability. Only 18.65% (2854 ha) of the municipality is agricultural land, of which just 4% (112 ha) currently benefits from irrigation. The NDVI-based classification achieved a Kappa coefficient of 0.88, indicating high reliability. Three sites demonstrated adequate storage capacity, with embankments measuring 8 m, 10 m, and 12 m in height. At one of these sites, two reservoirs arranged in a cascade were selected as an alternative to a single structure exceeding 12 m in height, thereby reducing environmental and landscape impact. The reservoirs fill between October and November in an average rainfall year and between October and January in a dry year, maintaining a positive annual water balance and allowing downstream plots to be irrigated by gravity. The methodology proved to be objective, replicable, and essential for the sustainable expansion of irrigation within the municipality.
- Evaluation of the impact of sustainable drainage systems (SuDSs) on stormwater drainage network using giswater: a case study in the metropolitan area of Barcelona, SpainPublication . Araújo, Suelen; Lança, Rui; Silva, Carlos Otero; Torret, Xavier; Granja Martins, Fernando Miguel; Maria Neto Paixão Vazquez Fernandez Martins, HelenaTo mitigate the impacts of urbanisation and the attendant surface sealing, appropriate measures are required when adapting urban spaces and drainage infrastructure. In this context, the deployment of Sustainable Drainage Systems (SuDSs) has emerged as a viable alternative, delivering highly positive outcomes by enhancing hydrological, hydraulic and landscape performance while restoring ecosystem services to the community. This study evaluates the relative performance of five SuDS typologies, green roofs, bioretention cells, infiltration trenches, permeable pavements, and rain barrels, implemented in a 64 ha subbasin of the metropolitan area of Barcelona, Spain. Using Giswater integrated with the SWMM, the stormwater drainage network was modelled under multiple rainfall scenarios. Performance was assessed using two qualitative indicators, the junction index (Ij) and the conduit index (Ic), which measure surcharge levels in manholes and pipes, respectively. The results show that SuDS implementation affecting 42.8% of the drained area can enhance network performance by 35.6% and reduce flooded junctions by 67%. Among the typologies, rain barrels and bioretention cells were the most effective. The study concludes that SuDS construction, supported by open-source tools and performance-based indicators, constitutes a replicable and technically robust strategy for mitigating the effects of surface sealing and increasing urban resilience.