Search results for "Elastic"
showing 10 items of 2162 documents
Investigation on the behaviour of fully thermoplastic composite sandwich beams under concentrated loads
2009
The recent development of new low cost manufacturing processes adopting thermoplastic matrices in the production of structural long fibre reinforced laminates is fostering an increasing interest towards this class of materials. The automotive sector in particular is attracted by the high energy absorbing, damage tolerance performances and manufacturing and recycling potentials of structural thermoplastic composites. In this study a number of fully thermoplastic sandwich beams have been manufactured in order to investigate flexural and shear rigidity performances as well as the indentation behavior under static concentrated loads.
SVILUPPI DELLA FOTOELASTICITÀ RGB
2007
Questa memoria considera le caratteristiche della fotoelasticità RGB con riferimento al massimo ordine di frangia rilevabile che dipende dalla modulazione del segnale, dalla sorgente luminosa, dalla presenza di colori simili e dal gradiente delle frange. Le esperienze mostrano che la lampada ad incandescenza consente di rilevare ritardi fino a circa 4 ordini di frangia mentre la lampada a fluorescenza consente di determinare ordini di frangia ben più elevati (12 in questa memoria) grazie alla natura discreta della sorgente.
Metodo automatici per l'analisi fotoelastica delle tensioni residue nel vetro
2010
Nei manufatti in vetro sono generalmente presenti tensioni residue provocate dalle lavorazioni. In tali componenti, il controllo delle tensioni residue riveste grande importanza; a tal fine si impiegano diversi metodi di analisi, codificati anche dalla normativa internazionale. Poiché il vetro è un materiale birifrangente, le tecniche sviluppate per l’analisi delle tensioni residue sono basate principalmente sul metodo fotoelastico. In questo lavoro vengono proposti due metodi automatici di analisi delle tensioni residue di tipo membranale nei vetri basati rispettivamente sulla fotoelasticità RGB, in luce bianca, e sul metodo a variazione di fase, in luce monocromatica. I suddetti metodi po…
Prestress and experimental tests on fractional viscoelastic materials
2013
Creep and/or Relaxation tests on viscoelastic materials show a power-law trend. Based upon Boltzmann superposition principle the constitutive law with a power-law kernel is ruled by the Caputo’s fractional derivative. Fractional constitutive law posses a long memory and then the parameters obtained by best fitting procedures on experimental data are strongly influenced by the prestress on the specimen. As in fact during the relaxation test the imposed history of deformation is not instantaneously applied, since a unit step function may not be realized by the test machine. Aim of this paper, it is shown that, the experimental procedure, and in particular the initial ramp to reach the constan…
Effective and Efficient Interpolation for Mutual Information based Multimodality Elastic Image Registration
2009
Mutual information (MI) is a popular similarity metric for multimodality image registration purpose. However, it is negatively influenced by artifacts due to interpolation effects. As a result, registration algorithms performance could be affected. In this paper a novel interpolation scheme is presented. It is both effective and efficient. Effective because it limits the presence of local maxima in the mutual information curve, efficient because it is simple to compute being based on simple and optimized distance measures. The method is validated and compared against other techniques both from performance and time complexity persepectives. Differently from other reference works, which perfo…
Increased expression of titin in mouse gastrocnemius muscle after an endurance-training program
2007
Titin, a sarcomeric giant protein, plays crucial roles in muscle assembly, elasticity and stability. Little is known about titin adaptation to endurance exercise. We studied the effects of endurance training on titin expression in mouse gastrocnemius muscles (MGM). Sixty-three ten-week-old male Swiss mice were divided into seven groups. Four groups were composed of untrained control animals (C0, C15, C30, C45) instead the other three included mice trained for 15 (T15), 30 (T30) and 45 (T45) days by treadmill. The training protocol was mainly aerobic, characterized by moderate-intensity, rhythmic and continuous exercises. Titin expression was determined by immunohistochemistry on MGM section…
Equilibrium in a duopoly game with homogeneous adaptive expectations and isoelastic demand
2011
In this paper we consider a non linear discrete time Cournot duopoly game with isoelastic demand and where players have homogeneous adaptive expectations. The evolution of expected outputs over time is generated by the iteration of two-dimensional map and the long-run behavior is characterized by equilibrium points which are locally stable.
La legatura elastica nel trattamento della emorragia da rottura di varici esofagee
2011
Nonlinearities in the Becker-Tomes-Solon model
2011
The aim of this paper is to explore nonlinearities in the relationship between parents and children earnings. We rst discuss a simple extension of the Becker-Tomes-Solon model accounting for nonlinearity. We then test the linearity of intergenerational transmission employing a set of 141 intergenerational mobility tables in 35 di erent countries at di erent time periods, and nd that linearity is rejected in 89 tables. We nally explore the correlation between the \strength of concavity" and income inequality. Our ndings suggest that more unequal societies tend to have a more concave intergenerational transmission process.
Ferroelastic transition in Kbr:Kcn studied by neutrons, x-rays and ultrasonic
1986
The ferroelastic phase transition of (KBr) 0 27 (KNC) 0.73 has been studied by X-ray diffraction, ultrasonics and inelastic neutron scattering. It is the first example of a cubic crystal where the elastic shear constant C 44 softens completely corresponding to the m = 2 universality class. C 44 and the Bragg intensities show a non-classical critical behaviour.