Search results for "threshold"
showing 10 items of 688 documents
Fast proton conduction in hydrogen bonded microheterogeneous systems: Bis(2-ethylhexyl)phosphoric acid/N-methyl formamide liquid mixtures
2009
Structural and dynamical properties of bis(2-ethylhexyl)phosphoric acid (HDEHP)/N-methyl formamide (NMF) liquid mixtures in the whole composition range have been investigated by Fourier Transform Infrared spectroscopy (FT-IR), X-rays Diffraction (XRD), and AC complex impedance spectroscopy. Driven by hydrogen bond interactions among HDEHP PO(4)H group and NMF CO and NH groups, and also by steric effects among the HDEHP alkyl chains, the system microstructure is mainly characterized by the coexistence of spatially separated hydrophilic and hydrophobic nanodomains showing local organization and short-range order. The evolution of this structural feature with system composition has been highli…
Limits of the linear viscoelastic behaviour of polyamide 66 filled with TiO2 nanoparticles: Effect of strain rate, temperature, and moisture
2008
Abstract Limits of linear viscoelastic behaviour of TiO 2 nanoparticle-filled polyamides are estimated quantitatively by the results of uniaxial tension tests. The stress limit of the filled polymer is higher than that of the un-filled one. Their values are the lower, the higher the temperature and moisture content of test specimens, and the lower, the lower the strain rate. The concept of an energy threshold for the linear viscoelastic behaviour is used to comprehensively characterize the limits over a wide range of test conditions. The energy limit is not affected by the strain rate, temperature, or moisture, and its value for the filled polymer is higher than that for the un-filled one. …
Correlations of the nonexponentiality and state dependence of mechanical relaxations with bond connectivity in Ge-As-Se supercooled liquids
1992
We have studied the mechanical responses of supercooled Ge-As-Se liquids to flexural strains and temperature steps. The departures from exponential relaxation correlate well with the variations in connectivity. The structural state dependence of the mechanical relaxation, detected in pure and weakly cross-linked Se, is suppressed completely at the rigidity percolation threshold {l angle}{ital r}{sub {ital c}}{r angle}, where the liquid fragility is a minimum. The shapes of the decay functions of samples with the same {l angle}{ital r}{sub {ital c}}{r angle} but different compositions are not universal at {ital T}{sub {ital g}} probably because of chemical effects near the binary edges of th…
Liquid crystalline polymers and elastomers
2002
The results of experiments and theory correlate increasingly well in the investigation of liquid crystalline polymers. Current work focuses on rheology and the behavior of blends of thermotropic LC polymers, due to reemerging economic interest in these materials. Research on liquid crystalline elastomers concentrates on potential applications such as artificial muscles and lasing.
Infrastrutture e paesaggio nella "città in estensione"
2017
L’esperienza didattica e di ricerca presentata nel saggio prende le mosse dall’attivazione di un laboratorio di laurea magistrale in Progettazione Architettonica diretto dal prof. Palazzotto e sviluppato nell’ambito del corso di laurea in Architettura dell’omonimo Dipartimento presso l’Università degli Studi di Palermo. Il laboratorio ha visto la partecipazione complessiva di 11 laureandi, che hanno esitato le proprie tesi negli anni compresi tra il 2013 e il 2015. Il laboratorio di laurea, facendo propria l’idea di “città-campagna” avanzata da Giuseppe Samonà nel 1976 – che porta con sé un esplicito riferimento a identità formali e spaziali specifiche intese a conferire allʼambito della ca…
SART and Individual Trial Mistake Thresholds: Predictive Model for Mobility Decline
2021
The Sustained Attention to Response Task (SART) has been used to measure neurocognitive functions in older adults. However, simplified average features of this complex dataset may result in loss of primary information and fail to express associations between test performance and clinically meaningful outcomes. Here, we describe a new method to visualise individual trial (raw) information obtained from the SART test, vis-à-vis age, and groups based on mobility status in a large population-based study of ageing in Ireland. A thresholding method, based on the individual trial number of mistakes, was employed to better visualise poorer SART performances, and was statistically validated with bin…
Intervención fisioterápica en el anciano con limitación funcional para las actividades de la vida diaria: estudio comparativo de la efectividad de do…
2011
Introducción.La pérdida generalizada de masa y fuerza muscular asociada al envejecimiento es causa de deterioro funcional y discapacidad física, especialmente en el anciano de edad avanzada. En este contexto, la función respiratoria puede verse gravemente comprometida, cuando al descenso fisiológico de la fuerza de la musculatura respiratoria (MR), se le suman la comorbilidad y la inmovilidad. Estudios previos han demostrado que el entrenamiento específico de la MR se acompaña de la mejora significativa de la fuerza y la resistencia de esta musculatura, tanto en sujetos sanos como en enfermos. Por lo tanto, puede tratarse de una intervención efectiva para mejorar y mantener las característi…
Protective coloration of European vipers throughout the predation sequence
2020
Antipredator adaptations in the form of animal coloration are common and often multifunctional. European vipers (genus Vipera) have a characteristic dorsal zigzag pattern, which has been shown to serve as a warning signal to potential predators. At the same time, it has been suggested to decrease detection risk, and to cause a motion dazzle or flicker-fusion effect during movement. We tested these hypotheses by asking whether (1) the zigzag pattern decreases detection risk and (2) the detection is dependent on the base coloration (grey or brown) or the snake's posture (coiled, basking form or S-shaped, active form). Additionally, (3) we measured the fleeing speed of adders, Vipera berus, an…
Pitch tilt rendering for an 8-DOF driving simulator
2015
International audience; Tilt coordination technique is used for reproducing a sustained linear acceleration in driving simulation by tilting the simulator cabin. Thus a part of gravity is interpreted as a horizontal acceleration. Between the slow rotational motion limited by the rotational perception threshold of semi-circular canals of vestibular system and the fast change of acceleration to render, the design of coupling motions of rotation and translation plays a critical role in the realism of driving simulator. We present here an experiment focusing on longitudinal accelerations rendering with pitch tilt coordination technique. Eight drivers experienced the same accelerations and decel…
Earnings management to exceed thresholds in continental and Anglo-Saxon accounting models: The British and French cases
2017
International audience; The purpose of this paper is to compare the extent to which French and British firms manage their earnings in order to avoid losses, decreases in earnings and earnings below the forecasts of analysts. Further, this study aims to investigate the factors that potentially influence earnings management to exceed thresholds with reference to the Anglo-Saxon and continental accounting models. Britain and France, correspondingly, belong to those different socio-economic environments. Based on a panel data of 1771 French and 2057 British firm-year observations during the period 2002–2012, we show that all firms considered manage earnings to beat zero and last year’s earnings…