Search results for "multilevel"
showing 10 items of 338 documents
Experimental Comparative Analysis of Efficiency and THD for a Three-phase Five-level Cascaded H-Bridge Inverter Controlled by Several MC-PWM Schemes
2021
Cascaded H-Bridges Multilevel Inverters are an innovative and promising solution in different application fields. This topology allows obtaining an improvement in the performance (e.g. reduced harmonic content, the low voltage stress on power components, and high efficiency) in respect to the traditional two-level inverters. In this context, the Multicarrier-PWM strategies play an important role thanks to their features. This paper presents an experimental investigation on the performance of a three-phase five-level Cascaded H-Bridge inverter by using different PWM modulation strategies. In particular, the paper is focused on the experimental validation of the main features of Multicarrier …
Mixed Harmonic Elimination Control for a Single-Phase 9 Level Grid-Connected Inverter
2018
The power quality requirements are increasingly stringent, due to the continuous growth of devices connected to the grid that introduce harmonics. These devices include DC to AC energy conversion systems, i.e. grid connected inverters. The design, control and operation of these systems must take into account the rules of interconnection to the electricity grid. To improve the quality of the output waveform of the grid-connected inverter, Multilevel Converters (MC) with selective harmonic elimination modulation technique can be used. This paper presents a single-phase nine level grid-connected inverter with DC/DC input stages. The obtained switching angles for THD minimization are independen…
Satisfaction with the clinical practice among nursing students using regression models and qualitative comparative analysis
2020
Abstract Background Clinical practice is considered fundamental in nursing studies for the effective education of nurses and students' satisfaction. Both the clinical environment and the clinical educator are key factors in students´ satisfaction. Objectives To analyze the influence of the socio-demographic variables of clinical educators and nursing students on satisfaction with the clinical practice. Design This was an observational, cross-sectional study. Settings A clinical practice course at a private university in Valencia, Spain. Participants The study included 527 nursing students enrolled on the clinical practice, supervised by 187 clinical educators. Methods Two statistical method…
Indoor noise exposure assessment of primary school children living in a french urban area
2012
International audience; The recent development of powerful noise mapping softwares allows to assess the exposure to environmental noise at the scale of an agglomeration. However noise levels inside dwellings are still unknown at such scales. To evaluate indoor noise levels and to investigate the factors which determine them, an eight-day noise measurement campaign was carried out in 50 childrens home. These children were randomly chosen among 8 or 9-year-old pupils attending the public primary schools of Besançon (France). Microphones were placed in the childs bedroom, outdoor in front of the bedrooms facade, and in the main room. Equivalent sound pressure levels (LAeq) were calculated d…
L'ACCESSO ALL'ABITAZIONE DI RESIDENZA: UN'ANALISI MULTILEVEL SULLE FAMIGLIE ITALIANE
2010
Objectives. Income inequalities depend on a large range of components, which influence living conditions of private households. Not all these elements are strictly monetary, and non-monetary components sometimes can be even more important than monetary ones. While international literature has devoted considerable attention to the study of distribution, relevance and inequalities concerning monetary income, the same cannot be said for its non monetary components. Despite this lack of attention in the literature, non monetary components often influence dramatically living conditions of private households. One of the most important component of non-monetary income is imputed rents from owner-o…
Simulating multilevel dynamics of antimicrobial resistance in a membrane computing model
2019
Membrane computing is a bio-inspired computing paradigm whose devices are the so-called membrane systems or P systems. The P system designed in this work reproduces complex biological landscapes in the computer world. It uses nested “membrane-surrounded entities” able to divide, propagate, and die; to be transferred into other membranes; to exchange informative material according to flexible rules; and to mutate and be selected by external agents. This allows the exploration of hierarchical interactive dynamics resulting from the probabilistic interaction of genes (phenotypes), clones, species, hosts, environments, and antibiotic challenges. Our model facilitates analysis of several aspects…
Engagement in entrepreneurship after business failure. Do formal institutions and culture matter?
2023
AbstractDespite the extensive literature on the relationship between entrepreneurship and institutions, there is limited knowledge of the relationship between institutions and engagement after failure. This study compares the entrepreneurial engagement of entrepreneurs who have recently experienced failure and individuals without entrepreneurial experience, emphasizing the interaction of government policies and programmes (formal institutions) and individualistic/collectivist cultures (informal institutions) with business failure and its impact on entrepreneurial engagement. We test our hypotheses using multilevel analysis on a large cross-sectional sample that combines individual-level dat…
<p>A Country Pandemic Risk Exposure Measurement Model</p>
2020
Purpose: The purpose of this study is to develop a Pandemic Risk Exposure Measurement (PREM) model to determine the factors that affect a country’s prospective vulnerability to a pandemic risk exposure also considering the current COVID-19 pandemic Methods: To develop the model, drew up an inventory of possible factor variables that might expose a country’s vulnerability to a pandemic such as COVID-19 This model was based on the analysis of existing literature and consultations with some experts and associa-tions To support the inventory of selected possible factor variables, we have conducted a survey with participants sampled from people working in a risk management environment carrying o…
Overview and experimental analysis of MC SPWM techniques for single-phase five level cascaded H-bridge FPGA controller-based
2016
This paper presents an overview and experimental analysis of the MC SPWM techniques for single-phase cascaded H-bridge inverter. The multilevel power converters are an alternative to traditional converters known as “three-level converters”. The voltage waveforms and the related frequency spectra, which have been obtained by simulation analysis in Matlab-Simulink environment, are here reported for all the proposed modulation techniques. The simulation results have been experimentally validated through means of a DC/AC, five-level, single-phase converter prototype with an appropriate test bench.
The effect of hotel chain affiliation on economic performance: The moderating role of tourist districts
2020
Abstract This paper offers a pioneering analysis of the impact that integration in different types of hotel chains has on firm performance, and the moderating effect of the tourist destination in this relationship. Studies in the literature examine both size and location independently, without reconciling the apparently contradictory trends of globalization and conservation of the local base. The aim of the research is to analyze the comparative effects on tourism firms’ performance of belonging to different types of hotel chains while maintaining the advantages of location in a tourist destination. Based on a study of 292 Spanish hotels, the authors test the proposed hypotheses using hiera…