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Presence and cybersickness in immersive content: Effects of content type, exposure time and gender
No full textEffects of PEV Traffic Flows on the Operation of Parking Lots and Charging Stations
Get PDFThe introduction of plug-in electric vehicles (PEVs) in the electrical system is bringing various challenges. The main issue is incorporating the PEV owner’s preferences in the models. One of the main attributes representing the preference of the owners is their travel purposes, impacting on the traffic flow pattern. The PEVs’ traffic pattern defines the required charging schedule of the PEVs and consequently characterizes the operation of the charging facilities such as PEV parking lots (PLs). The deployment of resources such as PEV PL requires a detailed modeling of the factors affecting their operation. In this regard, this paper aims to model the power flow of the PEVs based on their traffic flow. Different travel types and purposes are considered for the PEVs traffic modeling. Two types of charging infrastructure (i.e., PLs and individual charging stations) are considered. The study is performed on a distribution network categorized based on the consumption patterns of the zones. IEE
The effects of body position on Reflexive Motor Acts and the sense of presence in virtual environments
No full textMitigation in the Very Short-term of Risk from Wind Ramps with Unforeseen Severity
No full textThis paper addresses a critical analysis of the impact of the wind ramp events with unforeseen magnitude in power systems at the very short term, modeling the response of the operational reserve against this type of phenomenon. A multi-objective approach is adopted, and the properties of the Pareto-optimal fronts are analyzed in cost versus risk, represented by a worst scenario of load curtailment. To complete this critical analysis, a study about the usage of the reserve in the event of wind power ramps is performed. A case study is used to compare the numerical results of the models based on stochastic programming and models that take a risk analysis view in the system with high level of wind power. Wind power uncertainty is represented by scenarios qualified by probabilities. The results show that the reliability reserve may not be adequate to accommodate unforeseen wind ramps and therefore the system may be at risk
LASSO vector autoregression structures for very short-term wind power forecasting
Get PDFThe deployment of smart grids and renewable energy dispatch centers motivates the development of forecasting techniques that take advantage of near real-time measurements collected from geographically distributed sensors. This paper describes a forecasting methodology that explores a set of different sparse structures for the vector autoregression (VAR) model using the least absolute shrinkage and selection operator (LASSO) framework. The alternating direction method of multipliers is applied to fit the different LASSO-VAR variants and create a scalable forecasting method supported by parallel computing and fast convergence, which can be used by system operators and renewable power plant operators. A test case with 66 wind power plants is used to show the improvement in forecasting skill from exploring distributed sparse structures. The proposed solution outperformed the conventional autoregressive and vector autoregressive models, as well as a sparse VAR model from the state of the art. Copyright (c) 2016 John Wiley & Sons, Ltd
Vibration and Magnetic Field Sensing Using a Long-Period Grating
Get PDFA long-period grating (LPG) written on a standard single mode fiber is investigated as a fiber optic sensor for vibration and magnetic field sensing. It is demonstrated the high sensitivity of the device to applied curvature and the possibility to monitor vibration in a wide range of frequencies from 30 Hz to 2000 Hz. The system was tested using intensity-based interrogation scheme, providing a frequency discrimination of 913 mHz. The goal of these tests was to evaluate the sensor as a passive vibration monitor in the detection of changes in resonant vibration frequencies of support infrastructures can provide information on its degradation. Furthermore, taking advantage of the intrinsic sensitivity to micro strain, alternating magnetic fields were also measured using an intensity-based interrogation scheme by coupling a Terfenol-D magnetostrictive rod to a pre-strained LPG sensor, providing a resolution below 5.61 mu T-rms/root Hz from 1.22 mT(rms) up to 2.53 mT(rms)
A full scope web accessibility evaluation procedure proposal based on Iberian eHealth accessibility compliance
Get PDFInternet is becoming one of the most adopted technologies of all times and one of its particular uses concerns the public health issues. The search for health related information and the exchange of experiences and opinions on symptoms and treatments is one of the main activities associated with eHealth websites, hence the need for these websites to be accessible to everybody, including those with some sort of disability. Nevertheless, when assessing the level of the WCAG 2.0 compliance of Iberian eHealth websites, the results achieved during a two stage, one year apart, evaluation indicated that these websites were definitely not accessible. By adding this finding to other similar results achieved by means of similar researches we believe that a new full scope Web accessibility and usability evaluation procedure was needed and is now presented. The referred proposal aims at creating a basis for both organisations and Web developers to understand how to perform an adequate assessment of their websites. © 2016 Elsevier Ltd
Correlates of adults’ participation in sport and frequency of sport [Corrélats de la participation des adultes en sport et de la fréquence avec laquelle ils le pratiquent]
Get PDFThe aim of this research is to analyze the correlates of adults’ participation in sport and frequency of sport. A hurdle model approach comprising a binary choice regression to model participation in sport and a count model to address frequency of sport was applied to analyze the data obtained from 516 personal interviews in a Portuguese city. Participation in sport and frequent sport are associated with men, younger people, not married and without children under 2 years, nonsmokers and regular drinkers and with good perceived health. However, participation in sport and frequency of sport participation are associated with different levels of perception of the benefits of sport activity. Whereas awareness of the health and enjoyment benefits fosters participation, fitness, socializing and appearance might increase the frequency of sport. Sport communication strategies might play a prominent role in persuading potential participants of the benefits of sport activity and frequency. © 2017 Elsevier Masson SA