Evaluation of social personalized adaptive E-Learning environments : end-user point of view

The use of adaptations, along with the social affordances of collaboration and networking, carries a great potential for improving e-learning experiences. However, the review of the previous work indicates current e-learning systems have only marginally explored the integration of social features and adaptation techniques. The overall aim of this research, therefore, is to address this gap by evaluating a system developed to foster social personalized adaptive e-learning experiences. We have developed our first prototype system, Topolor, based on the concepts of Adaptive Educational Hypermedia and Social E-Learning. We have also conducted an experimental case study for the evaluation of the prototype system from different perspectives. The results show a considerably high satisfaction of the end users. This paper reports the evaluation results from end user point of view, and generalizes our method to a component-based evaluation framework

A review of inorganic photoelectrode developments and reactor scale-up challenges for solar hydrogen production

Green hydrogen, produced using solar energy, is a promising means of reducing greenhouse gas emissions. Photoelectrochemical (PEC) water splitting devices can produce hydrogen using sunlight and integrate the distinct functions of photovoltaics and electrolyzers in a single device. There is flexibility in the degree of integration between these electrical and chemical energy generating components, and so a plethora of archetypal PEC device designs has emerged. Although some materials have effectively been ruled out for use in commercial PEC devices, many principles of material design and synthesis have been learned. Here, the fundamental requirements of PEC materials, the top performances of the most widely studied inorganic photoelectrode materials, and reactor structures reported for unassisted solar water splitting are revisited. The main phenomena limiting the performance of up‐scaled PEC devices are discussed, showing that engineering must be considered in parallel with material development for the future piloting of PEC water splitting systems. To establish the future commercial viability of this technology, more accurate techno‐economic analyses should be carried out using data from larger scale demonstrations, and hence more durable and efficient PEC systems need to be developed that meet the challenges imposed from both material and engineering perspectives

Sizing solar-based mini-grids for growing electricity demand: insights from rural India

Mini-grids are a critical way to meet electricity access goals according to current and projected electricity demand of communities and so appropriately sizing them is essential to ensure their financial viability. However, estimation of demand for communities awaiting electricity access is uncertain and growth in demand along with the associated cost implications is rarely considered during estimation of mini-grid sizing. Using a case study of two rural communities in India, we assess the implications of demand growth on financial costs and performance of a mini-grid system consisting of solar photovoltaic (PV) panels and battery storage using two different system sizing approaches. We show a cost-saving potential of up to 12% when mini-grids are sized using a multi-stage approach where mini-grids gradually expand in several stages, rather than a single-stage optimisation approach. We perform a sensitivity analysis of the cost of the two sizing approaches by varying six key parameters: demand growth rate, logistics cost, system re-sizing frequency, likelihood of blackouts, solar PV and battery cost, and degradation rate. Of these, we find that system costs are most sensitive to variations in demand growth rates and cost decreases in solar PV and batteries. Our study shows that demand growth scenarios and choice of mini-grid sizing approaches have important financial and operational implications for the design of systems for rural electrification

Vector meson production and nucleon resonance analysis in a coupled-channel approach for energies m_N < sqrt(s) < 2 GeV II: photon-induced results

We present a nucleon resonance analysis by simultaneously considering all pion- and photon-induced experimental data on the final states gamma N, pi N, 2 pi N, eta N, K Lambda, K Sigma, and omega N for energies from the nucleon mass up to sqrt(s) = 2 GeV. In this analysis we find strong evidence for the resonances P_{31}(1750), P_{13}(1900), P_{33}(1920), and D_{13}(1950). The omega N production mechanism is dominated by large P_{11}(1710) and P_{13}(1900) contributions. In this second part we present the results on the photoproduction reactions and the electromagnetic properties of the resonances. The inclusion of all important final states up to sqrt(s) = 2 GeV allows for estimates on the importance of the individual states for the GDH sum rule.Comment: 41 pages, 26 figures, discussion extended, typos corrected, references updated, to appear in Phys. Rev.

Implementation of a neurophsiology-based coding strategy for the cochlear implant

Refractory State Coding (RSC) is a new coding strategy based on a functional model of the stimulated neural population. Our hypothesis is that RSC stimulation would convey the information contained in acoustic signals more effectively, improving sound perception and hearing performance for speech in noise and music. Two main factors that RSC takes into account are channel interaction [1] and refractory properties [2] of the stimulated neural population. They can be characterized by electrophysiological measurements of the evoked compound action potential (ECAP) using spread of excitation (SoE) and recovery function characterization paradigms respectively [3]. Using this information, for a given stimulus sequence, it is possible to calculate the refractory state of each stimulation site at any given time. In RSC, the stimulus is shaped according to the refractory states of stimulation sites. The spectral representation of the input sound is weighted by the refractory recovery information as well as the electric field distribution function before the next stimulus is selected. The Nucleus 24 and Nucleus Freedom family of cochlear implants incorporate Neural Response Telemetry (NRT) circuitry which is able to conveniently measure the ECAP from the implanted intracochlear electrodes, allowing the model to be custom-fitted to a patient. A software implementation of the standard ACE strategy for the Nucleus Cochlear Implant system is available in the Nucleus Matlab Toolbox. We implemented the RSC strategy in a compatible fashion in Matlab

A Theoretical Study of ρ 0-Photoproduction on Nucleons near Threshold

We investigate the possibility that the process of ρ0-meson photoproduction on proton, γ + p → p + ρ0, in the near threshold region Eγ &lt; 2 GeV, can be considered in the framework of model with π-, σ- and N-exchanges. This suggestion is based on a study of the t-dependence of differential cross section, dσ(γp → pρ0)/dt, which has been measured by SAPHIR Collaboration. We find that the suggested model provides a good description of the experimental data with new values of ρNN-coupling constants in the region of the time-like ρ0-meson momentum. Our results suggest that such model can be considered as a suitable nonresonant background mechanism for the future discussion of possible role of nucleon resonance contributions. Our predictions for ρ 0-meson photoproduction on neutron target and for beam asymmetry on both proton and neutron targets are presented. PACS numbers: 13.60.Le;13.60.-r;13.88.+e;24.70.+s;25.20.L

Implementation of a neurophysiologically-based coding strategy for the cochlear implant

Refractory State Coding (RSC) is a new coding strategy based on a functional model of the stimulated neural population. Our hypothesis is that RSC stimulation would convey the information contained in acoustic signals more effectively, improving sound perception and hearing performance for speech in noise and music. Two main factors that RSC takes into account are channel interaction [1] and refractory properties [2] of the stimulated neural population. They can be characterized by electrophysiological measurements of the evoked compound action potential (ECAP) using “spread of excitation” (SoE) and “recovery function” characterization paradigms respectively [3]. Using this information, for a given stimulus sequence, it is possible to calculate the refractory state of each stimulation site at any given time. In RSC, the stimulus is shaped according to the refractory states of stimulation sites. The spectral representation of the input sound is weighted by the refractory recovery information as well as the electric field distribution function before the next stimulus is selected. The Nucleus 24 and Nucleus Freedom family of cochlear implants incorporate Neural Response Telemetry (NRT) circuitry which is able to conveniently measure the ECAP from the implanted intracochlear electrodes, allowing the model to be custom-fitted to a patient. A software implementation of the standard ACE strategy for the Nucleus Cochlear Implant system is available in the Nucleus Matlab Toolbox. We implemented the RSC strategy in a compatible fashion in Matlab

Babacan_et_al_NATEN_2020_DATASET

This dataset contains the underlying data for the following publication: Babacan, O., De Causmaecker, S., Gambhir, A., Fajardy, M., Rutherford, A. W., Fantuzzi, A., & Nelson, J. (2020). Assessing the feasibility of carbon dioxide mitigation options in terms of energy usage. Nature Energy, 5(9), 720–728. https://doi.org/10.1038/s41560-020-0646-1. Full details of methods used to create the dataset are provided within this publication.This dataset contains the underlying data for the following publication: Babacan, O., De Causmaecker, S., Gambhir, A., Fajardy, M., Rutherford, A. W., Fantuzzi, A., & Nelson, J. (2020). Assessing the feasibility of carbon dioxide mitigation options in terms of energy usage. Nature Energy, 5(9), 720–728. https://doi.org/10.1038/s41560-020-0646-1. Full details of methods used to create the dataset are provided within this publication.