Search results for " modelling."

Application of computational fluid dynamics technique in electrodialysis/reverse electrodialysis processes

2022

This Chapter treats the application of CFD technique in ED/RED processes. CFD simulations are able to predict flow and mass transfer in channels filled with spacers or membrane profiles, by providing dimensionless correlations useful for process models. At a larger scale, manifolds of the stack and inlet/ outlet zones of the channel can be simulated. Numerical models can include the computation of the electrical potential, thus characterizing the process performance. Direct numerical simulations can elucidate the complex phenomenology of overlimiting transport and of chaotic electrokinetic flows.

Global sensitivity analysis in environmental water quality modelling: Where do we stand?

2014

Global sensitivity analysis (GSA) is a valuable tool to support the use of mathematical models for environmental systems. During the last years the water quality modelling field has embraced the use of GSA. Environmental water quality modellers have tried to transfer the knowledge and experience acquired in other disciplines. The main objective of this paper is to provide an informed problem statement of the issues surrounding GSA applications in the environmental water quality modelling field. Specifically, this paper aims at identifying, for each GSA method, the potential use, the critical issues to be solved and the limits identified in a comprehensive literature review. The paper shows …

Non-Linear Inductor Models Comparison for Switched-Mode Power Supplies Applications

2022

The use of non-linear power inductors, intended as devices exploited up to a current at which the inductance is halved, is of great interest in switched-mode power supplies (SMPSs). Indeed, it allows the use of lighter and cheaper inductors improving the power density. On the other hand, the analysis of SMPSs equipped with non-linear inductors requires appropriate modeling of the inductor reproducing the inductance versus current. This paper compares two main analytical models proposed in the literature: the former is based on a polynomial, and the latter exploits the arctangent function to reproduce the non-linearity of the inductance. Performance is compared by considering the effort of r…

Molecular modelling studies on dopamine-amino acid conjugates as potential dopaminergic modulators

2015

Students' Physical Activity, Physical Education Enjoyment, and Motivational Determinants through a Three-Year School-Initiated Program

2023

Patterns of physical activity in adulthood are often established during adolescence, making this an important period for promoting physical activity. To address this, the Sotkamo Physical Activity as Civil Skill Program 2010–2014 was implemented to increase Grade 5 to 9 students’ physical activity on a daily basis. The purpose of this study was to examine the effects of program on students’ physical activity and enjoyment. Furthermore, the relationship between motivational climate and enjoyment, and the percentages of students who engaged in 60 minutes of moderate to vigorous physical activity on the daily basis were examined.

Highly-parallelized simulation of a pixelated LArTPC on a GPU

2023

The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The alg…

Estimating Programming Exercise Difficulty using Performance Factors Analysis

2020

This Work in Progress Paper studies student and exercise modelling based on pass/fail log data gathered from an introductory programming course. Contemporary education capitalizes on the communications technology and remote study. This can create distance between the teacher and students and the resulting lack of awareness of the difficulties students encounter can lead to low student satisfaction, dropout and poor grades. In many cases, various technological solutions are used to collect individual exercise submissions, but there are little resources for indexing or modelling the exercises in depth. Exercise specific feedback from students may not be easily obtainable either. In the presen…

Intra‐individual dynamics of lesson‐specific engagement: Lagged and cross‐lagged effects from one lesson to the next

2020

Background Student engagement denotes active participation in academic work through commitment and involvement in learning tasks (Appleton et al., 2006, Journal of School Psychology, 44, 427). This study looks at questions such as whether engagement experiences in one lesson have an effect on the next lesson. In the present study, process‐oriented analyses were conducted to examine lower secondary school students’ engagement experiences and the stability of those experiences from one lesson to the next. Aims (1) To what extent are students’ engagement experiences, in terms of behavioural and cognitive engagement, emotional engagement, and disaffection, stable from one lesson to the next (au…

Organizational Wellness Modeling

2009

The aim of the present paper is to establish certain mathematical models for organizational wellness as well as to create some wellness optimization problems applicable to any type of organization (including universities) that might be mathematically solved resorting to aspects of operational research of mathematical analysis. The results obtained associated with a mathematical apparatus enable one to perform analyses, comparisons, interpretations, predictions. All of us have, consciously or not, a genuine curiosity in creating and shaping organizational wellness. This concept represents a highly topical issue since professional activity, irrespective of its field, holds a very significant …

Measuring the perceived value of rural tourism: a field survey in the western Sicilian agritourism sector

2016

Rural tourism constitutes a valuable tool for the sustainable development of many rural areas. This paper examines the concept of perceived value in rural tourism. A quantitative field survey was carried out in some main Western Sicilian holiday farms (agritourisms) during the Spring 2014. A theoretical model of the tourists’ perceived value in this specific context was developed and validated, using a 22-item scale. Using Partial Least Squares Path Modelling a theoretical structural model of the multidimensional structure of the RTPV was tested, assessing intensity and direction of the causal relationships among RTPV and its dimensions. Five dimensions were identified as forming the constr…