Search results for "equivalent"
showing 10 items of 308 documents
Some properties of multi-degree-of-freedom potential systems and application to statistical equivalent non-linearization
2003
This paper presents some properties of two restricted classes of multi-degree-of-freedom potential systems subjected to Gaussian white-noise excitations. Specifically, potential systems which exhibit damping terms with energy-dependent polynomial form are referred to. In this context, first systems with coupled stiffness terms and damping terms depending on the total energy are investigated. Then, systems with uncoupled stiffness terms and damping terms depending on the total energy in each degree-of-freedom are considered. For these two classes, it is found that algebraic relations among the stationary statistical moments of the energy functions can be derived by applying standard tools of…
Clinical microbeam radiation therapy with a compact source: specifications of the line-focus X-ray tube
2020
Highlights • Line-focus X-ray tubes are suitable for clinical microbeam radiation therapy (MRT). • A modular high-voltage supply safely enables high electron beam powers. • An electron accelerator was designed to generate an eccentric focal spot. • We simulated a peak-to-valley dose ratio above 20 for single-field MRT. • Microbeam arc therapy spares healthy brain tissue compared to single-field MRT.
ChemInform Abstract: Reaction of 4,5-Diamino-1,6-dihydropyrimidin-6-ones with Two Equivalents of Chalcones.
2010
The reaction of 4,5-diamino-1,6-dihydropyrimidin-6-ones 1 with two equivalents of the chalcones 2 leads in an acidic medium to the formation of the 2,3,6,7-tetrahydro-1H-pyrimido[4,5-b][1,4]diazepin-6-one derivatives 3a-d. The structure elucidation of the products is based on nmr measurements and an X-ray diffraction.
Effect of a prenatal lifestyle intervention on physical activity level in late pregnancy and the first year postpartum
2017
Background: Despite documented health benefits for mother and baby, physical activity (PA)-level tends to decline in pregnancy. Overweight/obese and physically inactive women are two selected groups at increased risk of pregnancy complications. Thus, efficient strategies to maintain or increase PA-level in pregnancy and the postpartum period, especially among these women, are warranted. This secondary analysis examined the effect of a prenatal lifestyle-intervention on PA-level in late pregnancy and the first year postpartum, with subanalysis on initially physically active versus inactive and normal-weight versus overweight/obese women. Method: The Norwegian Fit for Delivery (NFFD) randomiz…
Corporate Investment, Debt and Liquidity Choices in the Light of Financial Constraints and Hedging Needs
2015
We examine firms' simultaneous choice of investment, debt financing and liquidity in a large sample of US corporates between 1980 and 2014. We partition the sample according to the firms' financial constraints and their needs to hedge against future shortfalls in operating income. In contrast to earlier work, our joint estimation approach shows that cash flows affect the corporate decisions of unconstrained firms more strongly than those of constrained firms. Investment-cash flow sensitivities are particularly intense for unconstrained firms with high hedging needs. Investment opportunities (as proxied by Q), however, play a larger role for constrained firms with the effects being strongest…
Development of Antioxidant Protein Extracts from Gilthead Sea Bream (Sparus aurata) Side Streams Assisted by Pressurized Liquid Extraction (PLE)
2021
The pressurized liquid extraction (PLE) technique was used, for the first time, to obtain protein extracts with antioxidant activity from side streams (muscle, heads, viscera, skin, and tailfins) of gilthead sea bream (Sparus aurata) in order to give added value to these underutilized matrices. Extraction conditions previously optimized for sea bass (Dicentrarchus labrax) side streams were applied. Protein recovery percentages were 22% (muscle), 33% (heads), 78% (viscera), 24% (skin), and 26% (tailfins), which represented an increase of 1.2–4.5-fold compared to control samples (extraction by stirring). The SDS-PAGE profiles revealed that PLE-assisted extraction influenced protein molecular …
Frequency response of Measurement Current Transformers
2008
In this paper the frequency response of two CTs is experimentally evaluated in the range of 30-600 Hz. A theoretical analysis of CTs behavior has been developed by means of the equivalent circuit. It was shown, by an experimental test, that, for the frequency range analyzed, the transformer equivalent circuit is a valid tool for the evaluation of CT performances.
Vibro-acoustocal behavior of composite structures with damping elements
2013
This work is on the subject of modelization of structures treated with passive damping elements. A generic "equivalent single layer" plate model using transverse shear warping functions is presented. Several methods to obtain these functions are described, allowing the implementation of classical models and others issued from the litterature. Two new methods for obtaining these functions are also presented.Several discretization methods adapted to the generic plate model are studied. Navier's procedure allows the testing of the quality of each model associated with a set of transverse shear warping functions. Rayleigh-Ritz method allows the study of the vibrational behavior of a rectangular…
New insights into magma dynamics during last two eruptions of Mount Etna as inferred by geochemical monitoring from 2002 to 2005
2006
Two distinct eruptive events characterize the volcanic activity at Mount Etna during the 2002 to 2005 period. We identified signals of magma ascent preceding these eruptions by geochemical monitoring of both chemical composition and He-isotope ratio of gas emissions from five locations in the peripheral area of the volcano. The geochemical signals are interpreted using the models proposed by Caracausi et al. (2003a, 2003b) and allow identification of episodes of magma ascent and estimation of the pressures of degassing magma. As observed for the 2001 eruption (Caracausi et al., 2003b), magma ascent probably triggered the onset of the 2002–2003 eruption, and minor events of magma ascent were…
Association between education and future leisure-time physical inactivity: a study of Finnish twins over a 35-year follow-up
2016
Background: Education is associated with health related lifestyle choices including leisure-time physical inactivity. However, the longitudinal associations between education and inactivity merit further studies. We investigated the association between education and leisure-time physical inactivity over a 35-year follow-up with four time points controlling for multiple covariates including familial confounding. Methods: This study of the population-based Finnish Twin Cohort consisted of 5254 twin individuals born in 1945–1957 (59 % women), of which 1604 were complete same-sexed twin pairs. Data on leisure-time physical activity and multiple covariates was available from four surveys conduct…