Search results for "multilevel"

showing 10 items of 338 documents

Recursive Selective Harmonic Elimination for Multilevel Inverters: Mathematical Formulation and Experimental Validation

2023

A recursive method that eliminates +1 harmonics and their respective multiples from the output voltage of a cascaded H-bridge multilevel inverters with = 2 dc sources ( = 1, 2, 3,...) is proposed. It solves 2×2 linear systems with not singular matrices and always gives an exact solution with very low computational effort. Simulated results in three-phase five, nine, seventeen and thirty three level CHB inverters, and experimental results in five-level inverter demonstrate the validity of the method.

ModulationTotal Harmonic Distortion (THD)Multilevel InverterSelective Harmonics EliminationEnergy Engineering and Power TechnologyEfficiencySettore ING-IND/32 - Convertitori Macchine E Azionamenti ElettriciElectrical and Electronic EngineeringMultilevel Inverter Modulation Selective Harmonics Elimination Total Harmonic Distortion (THD) EfficiencyIEEE Journal of Emerging and Selected Topics in Power Electronics
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Students' school performance, task-focus, and situation-specific motivation

2015

Going beyond studies of individual differences in and profiles of students' motivation, we investigated situation-specific (intra-personal) experiences of autonomous (enjoyment, interest, and task choice) and controlled (having to do, and the teacher wanting them to do a task) motivation across learning situations during one week, and how these were related to student characteristics (teacher rated academic performance and task-focus). Three-hundred and fourteen primary school students (Years 5 and 6) completed electronic questionnaires on Personal Digital Assistants, on an average of 11.2 learning episodes during a week. Multilevel Structural Equation Models provided support for a model ba…

MotivationAutonomous and controlled motivationApplied psychologyGoal theoryAcademic performanceStructural equation modelingEducationFocus (linguistics)Task (project management)School performanceDevelopmental and Educational PsychologyComputingMilieux_COMPUTERSANDEDUCATIONMultilevel structural equation modelta516Task-focusFeature integration theoryPsychologyAssociation (psychology)Social psychologyta515Learning and Instruction
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Multilevel Power Relations and Planning Conflicts in a ‘Land of Exception’: The Case of the Sughereta di Niscemi Reserve in Sicily

2019

This article aims to investigate how the asymmetrical (political and economic) power relations can influence the effectiveness of planning systems at the local governance level, producing conflicting forms between land transformation and protection of natural interest sites. The article demonstrates how this condition can generate severe forms of environmental and social injustice through the case study of the M.U.O.S. of Niscemi (Mobile User Objective System). M.U.O.S. of Niscemi is a ground station for military communications satellite system, constructed by the United States Navy (Department of Defense) in Zone B of the natural reserve of "Sughereta di Niscemi" (the most relevant relict …

Multilevel PowerPlanning ConflictSettore ICAR/20 - Tecnica E Pianificazione Urbanisticastate of ExceptionSettore ICAR/21 - UrbanisticaSicily
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Perceived Reciprocity and Well-Being at Work in Non-Professional Employees: Fairness or Self-Interest?

2012

This article assesses the links between non-professional employees' perceptions of reciprocity in their relationships with their supervisors and the positive and negative sides of employees' well-being at work: burnout and engagement. Two hypotheses were explored. First, the fairness hypothesis assumes a curvilinear relationship where balanced reciprocity (when the person perceives that there is equilibrium between his/her efforts and the benefits he/she receives) presents the highest level of well-being. Second, the self-interest hypothesis proposes a linear pattern where over-benefitted situations for employees (when the person perceives that he/she is receiving more than he/she deserves)…

Multilevel modelOrganizational cultureSample (statistics)General MedicineBurnoutPsychiatry and Mental healthClinical PsychologyInterpersonal relationshipWell-beingJob satisfactionPsychologySocial psychologyApplied PsychologyReciprocity (cultural anthropology)Stress and Health
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Personal goal appraisals vary across both individuals and goal contents

2009

Abstract This study examined personal goals as a multilevel construct. After investigating to what extent goal appraisals were characteristics of an individual as compared to the extent to which they vary across different goals, both individual-level and goal-level predictors of goal appraisals were examined. To examine these research questions 477 undergraduates filled in the Personal Project Analysis and Beck’s Depression inventory. Multilevel modeling showed that, although goal appraisals varied between individuals, they differed to greater extent across the different goals a particular person reported. At the individual level, a high amount of depressive symptoms was associated with a l…

Multilevel modelStress (linguistics)Well-beingControl (management)Research questionsConstruct (philosophy)PsychologyGeneral PsychologyProject analysisDevelopmental psychologyMeaning (linguistics)Personality and Individual Differences
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ESE. Estudios sobre educación

2021

espanolEste estudio pretende avanzar en la comprension de la relacion entre el profesor y el estudiante universitario con el objetivo de mejorar el rendimiento de los estudiantes. Se articula sobre tres ejes: el enfoque de rendimiento del estudiante, la relacion entre diversos aspectos del profesor y, fi nalmente, el efecto de estos aspectos sobre el rendimiento del estudiante. Los resultados obtenidos de una muestra de 45 profesores y 932 estudiantes muestran que la orientacion al estudiante por parte del profesor afecta al aprendizaje percibido y a la satisfaccion del estudiante. Se alcanzan otros interesantes resultados que permiten establecer ciertas conclusiones e implicaciones. Englis…

Multilevel modelsBurnout/engagementrelación profesor-alumnomotivación del rendimientoOrientación del profesorOrientation (graph theory)conducta del profesorEducationTeachers' orientationorientación pedagógicaestudianteenseñanza superiorSEMComputingMilieux_COMPUTERSANDEDUCATIONOrientación del estudianteModelos multinivelStudent orientationlcsh:LPsychologyHumanitiesactitud hacia el trabajoUniversity teachers and studentslcsh:EducationProfesor y estudiante universitarioEstudios sobre Educación
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The competency-based approach in developing countries : effects of curricular reforms in Sub-Saharan Africa

2013

For decades, all analyzes converge on the idea of the relative inefficiency of education systems in sub-Saharan Africa. Dropout, repetition, overstaffing, low quality of learning student failure and obsolescence of facilities, teaching materials and teachers, including sometimes the levels and quality of education remain somewhat uncertain, inadequate educational programs. In short, these are some of the ills that plague these systems and confirm the findings made by many reports. Given this weakness finding, educational authorities, supported by international aid mobilized in many countries to improve their systems to qualitatively, but also quantitatively equity because we must not forget…

Multilevel modelsCompetency-based approachesApproches par compétencesTeaching[SHS.EDU] Humanities and Social Sciences/EducationRéformes curriculumModèles multiniveauxPratiques pédagogiquesCurriculum reformEnseignementInstructional practices
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Les langues, facteurs du rendement en lecture dans les évaluations PIRLS

2011

The starting point of this research is the question, may reading acquisition be more or less effective depending on the language in which it is perform? Two categories for classifying the languages have been developed. First the notion of linguistic family is employed to describe the languages from a cultural and historical perspective. Secondly, the notion of orthographic depth is used for differentiating the languages according to the correspondence between orthography and phonetic. These categories have been related to the databases PIRLS 2001 and 2006 (international assessments about reading developed by the IEA), the aim being to connect reading achievement to the language in which stu…

Multilevel modelsReading learningModèles multi-niveaux[SHS.EDU]Humanities and Social Sciences/EducationInternational comparisonsProfondeur orthographiqueComparaisons internationales[SHS.EDU] Humanities and Social Sciences/EducationLinguistic familiesOrthographic depth[ SHS.EDU ] Humanities and Social Sciences/EducationFamilles linguistiquesAcquisition de la lecture
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PISA 2000 results of reading literacy in Finland

2005

Multilevel modelsalueelliset erotkoulutPISA-tutkimuskoulusaavutuksetSchool differencesoppimistuloksetoppilaatkansainvälinen vertailuInequityperhetaustaEducationsukupuoliLiteracyReadinglukutaitoerotFinlandmenestyminen
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Anterior palatoplasty: Effectiveness for treatment of simple snoring and mild osas

2017

Positive airway pressure is the treatment of choice among obstructive sleep apnea syndrome patients. Among surgical options, multilevel approach is a good option in patients with an involvement of all tract of first airway. The aim of the present work is to establish the efficacy of anterior palatoplasty in the treatment of selected patients with mild obstructive sleep apnea syndrome or simple snoring, within a multilevel surgery. The group was composed of 16 mild obstructive sleep apnea syndrome adult patients collected from January 2015 to June 2016 at University of Palermo, Ear, Nose and Throat Department. To make diagnosis of obstructive sleep apnea syndrome, we employed polysomnography…

Multilevel surgeryMedicine (all)SnoringOSASMultilevel surgery; OSAS; Pharyngoplasty; Snoring; Medicine (all)Pharyngoplasty
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