Search results for "Drive"

The Thin Ideal and Attitudes towards Appearance as Correlates of Exercise Addiction among Sporty People during the COVID-19 Pandemic

2022

The stress and anxiety caused by the coronavirus pandemic (COVID-19) have exacerbated body image concerns. A society that perpetuates the attempt for a perfect and thin appearance represents a fertile ground for the development of exercise addiction (EA). This cross-sectional study aims to explore EA during the second wave of the pandemic (October–December 2020) and to examine the independent influence of both time spent on moderate and vigorous physical activities and body image variables (i.e., drive for leanness and sociocultural attitudes toward appearance) on EA. A sample of Italian sporty people (N = 194; 48.5% females; Mage = 25.91 ± 6.32) was surveyed using the Exercise Addiction In…

A Bibliometric Analysis of the HICSS Software Technology Track

2020

The HICSS Software Technology track has a long tradition and many papers have been published as part of its history. Its impact in terms of citations, paper contributions, author share and community impact does not yet seem to have been investigated, though. In particular, software technology has evolved, and as it stands, it is of primary importance for mobile computing, the Internet-of-Things and Cyber-physical Systems. Hence, the development of these topics and the related impact of this track are of particular interest. In this paper, we present a bibliographic analysis as a first step towards such an investigation. We found that the history of the track is indeed noteworthy. Our result…

Deep learning and process understanding for data-driven Earth system science

2017

Machine learning approaches are increasingly used to extract patterns and insights from the ever-increasing stream of geospatial data, but current approaches may not be optimal when system behaviour is dominated by spatial or temporal context. Here, rather than amending classical machine learning, we argue that these contextual cues should be used as part of deep learning (an approach that is able to extract spatio-temporal features automatically) to gain further process understanding of Earth system science problems, improving the predictive ability of seasonal forecasting and modelling of long-range spatial connections across multiple timescales, for example. The next step will be a hybri…

On Big Data: How should we make sense of them?

2020

The topic of Big Data is today extensively discussed, not only on the technical ground. This also depends on the fact that Big Data are frequently presented as allowing an epistemological paradigm shift in scientific research, which would be able to supersede the traditional hypothesis-driven method. In this piece, I critically scrutinize two key claims that are usually associated with this approach, namely, the fact that data speak for themselves, deflating the role of theories and models, and the primacy of correlation over causation. In so doing, I will also refer to a recent case history of data mining projects in the field of biomedicine, i.e. EXPOsOMICS. My intention is both to acknow…

The variations of technical and allocation coefficients : are they comparable really ?

1995

Two great alternative hypothesis are possible in the analysis input-output : the model may be demand-driven (Leontief) or supply-driven (Ghosh). To test the consistency of these hypotheses on the long term, this paper studies the interest of proportional filters (comparison of column or row coefficients) and the interest of the biproportional filter for the temporalcomparison of input-output matrices. An application is proposed for France between 1980 and 1993. The result is the following : in the long period, there are more sectors supply-driven than demand-driven (i.e. row coefficients are less variable than column coefficients for the majority of the sectors). (FRE) Deux grandes hypothès…

A biproportional filter to compare technical and allocation coefficient variations

1997

International audience; In input-output analysis there are two alternate possibilities between Leontief's mechanism (fixed technical coefficients) and Ghosh's mechanism (fixed allocation coefficients). Testing the long term consistency of these mechanisms entails comparing input-output matrices over time. This paper challenges the value of proportional filters (separate comparison of column and row coefficients) and introduces the biproportional filter which allows simultaneous comparison of column and rows. An application is proposed using French input-output tables for 1980 and 1993. The stability of column coefficients cannot be taken for granted and generally, for any sector, both rows …

Back EMF Sensorless-Control Algorithm for High-Dynamic Performance PMSM

2010

In this paper, a low-time-consuming and low-cost sensorless-control algorithm for high-dynamic performance permanent-magnet synchronous motors, both surface and internal permanent-magnet mounted for position and speed estimation, is introduced, discussed, and experimentally validated. This control algorithm is based on the estimation of rotor speed and angular position starting from the back electromotive force space-vector determination without voltage sensors by using the reference voltages given by the current controllers instead of the actual ones. This choice obviously introduces some errors that must be vanished by means of a compensating function. The novelties of the proposed estima…

Automotive Brushless Motor Powered by Fuel Cell

2014

Cascaded H-Bridges Multilevel Inverter Drive: Active Power Analysis in Frequency Domain

2022

The international standard IEC 61800-9-2 introduces energy efficiency classification for frequency converters or complete drive module (CDM) and provides instrumentation minimum requirements for accurate measurement of CDM input and output power valid for conventional pulse-width-modulated (PWM) voltage source inverter (VSI). This paper highlights the necessary improvements to update the standard with more detailed prescriptions according to the converter topologies and the modulation techniques adopted. In this framework, this paper address the power analysis in the frequency domain of a cascaded H-bridges-multilevel inverter (CHBMI) in an interior permanent magnet synchronous motor (IPMSM…

A novel method for harmonic mitigation for single-phase five-level cascaded H-Bridge inverter

2018

The efficiency of a system is a very important parameter for high power electrical drives applications. Moreover, the efficiency of power converters plays a fundamental role. Aim of this work, is to propose a novel selective harmonic mitigation method without solving non-linear equations. Through a very simple approach, the polynomial equations which drive the control angles have been detected for a single-phase five-level cascaded H-Bridge inverter. The obtained polynomial equations can be easily implemented in a digital system to real-time operation. The paper also presents the simulation analysis and experimental validation.