Search results for "Liability"
showing 10 items of 1754 documents
Optimal matching between optical rectennas and harvester circuits
2017
This paper deals with optimal coupling issues between rectennas and harvesting circuits. An optical rectenna consists of a nanoantenna usually coupled with an ultra-high speed rectifier. These devices aim to receive and convert solar and thermal radiation in a DC voltage, while a harvester circuit provides the energy to be stored. The rectenna impedance is influenced both by its structure and by the rectifying diode, the harvester circuit impedance has to be matched to optimize the power transfer. The purpose of this contribution is to discuss the best impedance conditions by taking into account the constraints that are due to the individual devices the conversion system consist of. Finally…
A multi-input, single-inductor power system for multisource energy harvesting
2013
Today, energy harvesting is drawing a great deal of attention due to modern trends in energy saving and sustainable development purposes. Among renewable energy sources fuel cells and photovoltaic arrays are the most promising for a wide variety of applications, ranging from few mWatts of wireless sensor networks to kWatts for household appliances. Coupling several harvesters and renewable sources is the winning strategy to ensure a proper supply overcoming the uncertainty and limited availability of common harvesters and renewable sources. Multisource energy harvesting is actually an open research topic involving several pressing and often conflicting requirements. System cost, complexity,…
Development of an individualized familiarization method for vertical jumps
2013
OBJETIVO: Propor um método de familiarização individualizado para saltos verticais e verificar o seu efeito na variabilidade intrassujeito. MÉTODOS: Cinquenta e três homes (média ± DP; idade 23,5 ± 3,3 anos; estatura 1,76 ± 0,08 m; massa 72,8 ± 8,6 kg; percentual de gordura 12,9 ± 5,2%) realizaram sucessivos saltos até atingir o nível de estabilidade proposto. Após 48 h este processo era repetido e a estabilidade entre dias era verificada, se necessário, mais sessões eram realizadas. O nível de estabilidade foi determinado por um teste z, com intervalo de confiança de 95%. Após o processo de familiarização, duas sessões experimentais adicionais foram realizadas para determinar a confiabilid…
Impact of humic acids on EYL liposome membranes: ESR method
2015
Abstract In this paper, the effects of model (commercial) and natural (extracted from peat) humic substances on the membrane of liposomes formed with egg yolk lecithin (EYL) are presented. In our research, mass concentrations of fulvic and humic acids were used, which in relation to lecithin varied from 0% to 13%. To study membrane fluidity, electron spin resonance (EPR) was used with two spin probes, penetrating various regions of the lipid bilayer. The effects of model and natural humic substances (humic acids – HAs and fulvic acids – FAs) on the lipid membrane in different regions were researched: the lipid-water interphase, and in the middle of the lipid bilayer. It was shown that FA an…
The Comparison of Software Reliability Assessment Models
2015
Abstract The reliability of the software represents one of the most important attributes of software quality, and the estimation of the reliability of the software is a problem hard to solve with accuracy. Nevertheless, in order to manage the quality of the software and of the standard practices in an organization, it is important to achieve an estimation of the reliability as accurate as possible. In the present work there are described the principles and techniques which underlie the estimation of the reliability of the software, starting from the definition of the concepts which express the attributes of software quality. It is taken into account the issue of the estimation of a software…
Fiabilidad y evidencias de validez de un instrumento para la evaluación de la calidad de los mapas conceptuales
2017
Diversos autores han señalado el interés y la pertinencia de los mapas conceptuales como herramientas para el aprendizaje significativo. Sin embargo, la revisión de la literatura pone de manifiesto la escasez de propuestas dirigidas a la evaluación de los mapas con criterios objetivables y la complejidad de las existentes. El objetivo del presente estudio fue desarrollar un instrumento para la evaluación de los mapas conceptuales en formato rúbrica. De esta manera, se consigue que los alumnos posean una herramienta que permita, mediante indicadores precisos, la evaluación de la calidad tanto de sus ejecuciones como de las ejecuciones realizadas por otros. Se construyó una rúbrica que incluy…
Ocena wiarygodności internetowych serwisów wybranych polskich wyższych uczelni niepublicznych
2019
Celem artykułu jest dokonanie i przedstawienie oceny wiarygodności internetowych serwisów wybranych polskich wyższych uczelni niepublicznych. Koncepcja, metody badań: Sięgając do definicji terminów związanych z pojęciem wiarygodność odniesiono je do serwisów internetowych. Na tej podstawie stworzono konceptualne ramy oceny wiarygodności dla takich serwisów. Ramy te posłużyły do oceny wiarygodności internetowych serwisów wybranych wyższych uczelni niepublicznych w Polsce z wykorzystaniem metody sondażowej i oryginalnego narzędzia. Ranking wiarygodności badanych serwisów internetowych utworzono wykorzystując metodę TOPSIS. Wyniki i wnioski: W artykule pokazano, że zestaw cech i kryteriów używ…
Reliability of measurements during countermovement jump assessments: Analysis of performance across subphases
2020
The aim of this study was to examine the reliability of performance measures in the different phases and sub-phases of the countermovement jump (CMJ). Seventeen male athletes competing at a regional level completed 204 valid trails consisting of the execution of maximal hands-on-waist CMJs performed on a force platform. The vertical ground reaction force (VGRF) data obtained at a sampling frequency of 1000 Hz were used to calculate performance-derived variables and determine key points and jump sub-phases. The relative reliability of 92 variables was assessed using the intraclass correlation coefficient (ICC) from a two-way mixed effects model analyzing the time, force, power, velocity, and…
Memory‐type control charts for censored reliability data
2023
Control charts are commonly used to monitor a process to detect undesirable changes. The main goal of this work is to propose exponentially weighted moving average (EWMA) and cumulative sum (CUSUM) control charts to track a process by utilizing type-I censored generalized exponential (GE) distributed data. In particular, the censored data are replaced with the conditional expected value (CEV). A comparison between CUSUM and CUSUM ignoring unobserved covariates (CUSUM-IUC) charts is also a part of this study. The GE distribution is considered due to its application in reliability analysis. The performance of the charts is evaluated by using the average run length along with the standard devi…
Translation and validation of Brunel Mood Scale for Serbian athlete population
2014
Ivica Rajkovic, 2014. Translation and validation of Brunel Mood Scale for Serbian athlete population. Master Thesis in Sport and Exercise Psychology. Department of Sport Sciences, University of Jyväskylä. 40p. Present study developed and validated the Serbian version (SERMS) of Brunel Mood Scale (BRUMS). BRUMS is 24 item questionnaire used to asses mood profile on six subscales (anger, confusion, depression, fatigue, tension and vigour). BRUMS was translated in to the Serbian using translation-back translation method, and administered to 354 athletes in Serbia and Montenegro. Exploratory factor analysis (EFA) and Cronbach’s alpha were used to determine factor validity and internal consisten…