698 research outputs found

    The clustering conditions for managing creative tourism destinations: the Alqueva region case, Portugal

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    This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this recordThe paper discusses conditions and format of a cluster model to support the management of a potential creative tourism destination in a setting where regional cross-sectoral collaboration is lacking. Creative tourism development requires a flexible framework and a healthy collaboration environment, more so when associated with resources shared by several stakeholders. This article focuses on the tourism potential of archaeological knowledge discovered during the environmental impact assessment of the Alqueva dam (Alentejo, Portugal). Interviews were conducted with 38 regional actors in the tourism and heritage sectors, as well as the dam developers and the companies responsible for archaeological interventions. Findings indicate that the lack of specific local policy addressing archaeological heritage hampers its potential use for tourism development, which is further aggravated by the absence of stakeholder communication and cooperation. A conceptual cluster model for the management of creative tourism destinations based on heritage resources and other local resources is proposed.Portuguese national funding agency for Science, Research and Technology (FCT

    Short-term water demand forecasting using machine learning techniques

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    Nowadays, a large number of water utilities still manage their operation on the instant water demand of the network, meaning that the use of the equipment is conditioned by the immediate water necessity. The water reservoirs of the networks are filled using pumps that start working when the water level reaches a specified minimum, stopping when it reaches a maximum level. Shifting the focus to water management based on future demand allows use of the equipment when energy is cheaper, taking advantage of the electricity tariff in action, thus bringing significant financial savings over time. Shortterm water demand forecasting is a crucial step to support decision making regarding the equipment operation management. For this purpose, forecasting methodologies are analyzed and implemented. Several machine learning methods, such as neural networks, random forests, support vector machines and k-nearest neighbors, are evaluated using real data from two Portuguese water utilities. Moreover, the influence of factors such as weather, seasonality, amount of data used in training and forecast window is also analysed. A weighted parallel strategy that gathers the advantages of the different machine learning techniques is suggested. The results are validated and compared with those achieved by autoregressive integrated moving average (ARIMA) also using benchmarks.publishe

    Increased performance in the short-term water demand forecasting through the use of a parallel adaptive weighting strategy

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    Recent research on water demand short-term forecasting has shown that models using univariate time series based on historical data are useful and can be combined with other prediction methods to reduce errors. The behavior of water demands in drinking water distribution networks focuses on their repetitive nature and, under meteorological conditions and similar consumers, allows the development of a heuristic forecast model that, in turn, combined with other autoregressive models, can provide reliable forecasts. In this study, a parallel adaptive weighting strategy of water consumption forecast for the next 24–48 h, using univariate time series of potable water consumption, is proposed. Two Portuguese potable water distribution networks are used as case studies where the only input data are the consumption of water and the national calendar. For the development of the strategy, the Autoregressive Integrated Moving Average (ARIMA) method and a short-term forecast heuristic algorithm are used. Simulations with the model showed that, when using a parallel adaptive weighting strategy, the prediction error can be reduced by 15.96% and the average error by 9.20%. This reduction is important in the control and management of water supply systems. The proposed methodology can be extended to other forecast methods, especially when it comes to the availability of multiple forecast models.by UE/FEDER through the program COMPETE 2020 and UID/EMS/00481/2013-FCT under CENTRO-01-0145-FEDER- 022083publishe

    Report Card on Physical Activity for Children and Youth

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    Background: This article describes the procedures and development of the rst Portuguese Report Card on Physical Activity in Children and Adolescents. Methods: Comprehensive searches for data related to indicators of physical activity (PA) were completed by a committee of physical activity and sports specialists. Grades were assigned to each indicator consistent with the process and methodology outlined by the Active Healthy Kids Canada Report Card model. Results: Nine indicators of PA were graded. The following grades were assigned: Overall Physical Activity Levels, D; Organized Sport Participation, B; Active Play, D; Active Transportation, C; Sedentary Behaviors, D; Family and Peers, C; Schools, B; Community and the Built Environment, D; and Government, C. Conclusions: Portuguese children and adolescents do not reach suf cient physical activity levels and spend larger amounts of time spent in sedentary behaviors compared with recommendations. Effective policies of PA promotion and implementation are needed in different domains of young people’s daily lives

    Magnetron sputtering thin films as tool to detect triclosan in infant formula powder: Electronic tongue approach

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    This work was supported by the Project "Development of Nanostructures for Detection of Triclosan Traces on Aquatic Environments" (PTDC/FIS-NAN/0909/2014). The Center for Environmental and Sustainability Research (CENSE) and Centre of Physics and Technological Research (CEFITEC), which is financed by national funds from FCT/MEC (UID/AMB/04085/2019 and UID/FIS/00068/2019). The authors also acknowledge and appreciate the support given to Center for Environmental and Sustainability Research (CENSE) and Centre of Physics and Technological Research (CEFITEC) by the Portuguese Foundation for Science and Technology (FCT) through the strategic project UIDB/04085/2020 and UID/FIS/00068/2020.Triclosan (TCS) is being detected in breast milk and in infants of puerperal women. The harmful effects caused by this compound on living beings are now critical and thus it is pivotal find new tools to TCS monitoring. In the present study, an electronic tongue (e‐tongue) device comprising an array of sputtered thin films based on Multi‐Walled Carbon Nanotubes and titanium dioxide was developed to identify TCS concentrations, from 10−15 to 10−5 M, in both water and milkbased solutions. Impedance spectroscopy was used for device signal transducing and data was analyzed by principal component analysis (PCA). The e‐tongue revealed to be able to distinguish water from milk‐based matrices through the two Principal Components (PC1 and PC2), which represented 67.3% of the total variance. The PC1 values of infant formula milk powder prepared with tap water (MT) or mineral water (MMW) follows a similar exponential decay curve when plotted with the logarithm of concentration. Therefore, considering the TCS concentration range between 1015 and 10−9 M, the PC1 values are fitted by a straight line and values of −1.9 ± 0.2 and of 7.6 × 10−16 M were calculated for the sensor sensitivity and sensor resolution, respectively. Additionally, a strong correlation (R = 0.96) between MT and MMW PC1 data was found. These results have shown that the proposed device corresponds to a promisor method for the detection of TCS in milk‐based solutions.publishersversionpublishe

    NEW EQUATIONS TO DETERMINE EXERCISE INTENSITY USING DIFFERENT EXERCISE MODES

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    The purpose of this study was to determine new equations from the relationship of %·VO2max versus %HRmax, based on direct measures of oxygen uptake, in four exercise modes (leg cycling, rowing, stepping and running), in young adult females and males with low risk for cardiovascular disease. Ten adult males and ten females volunteered for the study. The participants performed an incremental test for each exercise mode until exhaustion. Regression analyses were carried out for each participant at a target % of VO2max and %HRmax was computed. At 40-90%·VO2max, the regression equations predicted similar values of %HRmax for males and females in the four exercise modes. In contrast, estimated %HRmax for cycling was higher at 40-70%·VO2max, when compared with stepping and running. The results support the notion that a single equation to predict target heart rate values for both males and females can be applied. Furthermore, at light and moderate intensities, leg cycling produces different %·VO2max-%HRmax regression equations than stepping and running

    TBW Assessment by Deuterium Dilution in Spanish Adolescents

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    Congreso para especialistas en Nutrición, Actividad Física y Composición CorporalINTRODUCTION: Total body water (TBW) assessment is a cornerstone in order to validate equations to estimate body composition components as fat mass and fat free mass. Deuterium dilution technique (D2DT) is considered the gold standard method to assess TBW, however in Spain there are not any reference data using D2DT. The knowledge of specific references for Spanish population must be a goal for the biological studies of Spanish people. OBJECTIVE: It was our aim to assess TBW using the D2DT in a sample of Spanish adolescents. METHODS: 224 specimens of urine from 150 adolescents (113 girls and 111 boys) were taken to analyze. A dose of 0.1 grams of 2D2O per Kg of body weight was administrated; afterwards it was followed by 4-hours stabilization period. The isotope (deuterium oxide (D2O)) dilution method was used to measure TBW with an isotope-ratio mass-spectrometer. Averages by sex and Tanner stages were calculated for %TBW and TBW. General lineal model were used to analyze differences and interactions between groups. RESULTS: %TBW was significantly different between boys and girls (58.98_5.59% vs 55.5_4.28%, P0.05). CONCLUSIONS: This study has been the first in Spain, which have measured TBW in vivo using D2DT. These data can be useful to validate new methods and equations from bioimpedance analysis to estimate TBW.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Coca-Col
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