305,415 research outputs found
Corpus vivens: Gerarchie del sapere nelle università tra XII e XIV secolo
No full textEl ensayo discute el lazo entre disputación escolástica, reactivación del Aristotelismo y renacimiento del derecho romano en las universidades entre el siglo XIII y XIV.Fil: Rustighi, Lorenzo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Il governo della madre: Percorsi e alternative del potere in Rousseau
No full textEn un enfrentamiento con la obra de Rousseau, este libro toma en serio la hipótesis de Foucault según la cual el Estado no sería más que una peripecia de las artes de gobierno. Por lo tanto, es cuestión de seguir las huellas del filósofo de Ginebra para comprender cómo y por qué ha articulado este camino, poniendo a prueba su consistencia, pero también sus alternativas y sus aporías. A partir de la cuestión de la democracia, el horizonte a la vez necesario e imposible de proyecto político de Rousseau, siempre sometida al exceso del gobierno de los hombres dentro de la forma política y sin embargo siempre revivida a través de estrategias en las cuales la lógica del poder soberano aparece en transparencia, frágil y compleja.La más significativa de estas estrategias es la de la sexuación. El "gobierno de la madre" se asume aquí como un prisma a través del cual se pueden leer la operación filosófica y la ontología política de Rousseau. El cuerpo materno es, de hecho, el campo de batalla en el que se resuelven los conflictos entre una serie de Razones Estatales competidoras, poniendo continuamente en juego la tensión entre los dispositivos de legitimidad política y los dispositivos de gubernamentalidad.Fil: Rustighi, Lorenzo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
An experimental approach for the determination of axial and flexural wavenumbers in circular exponentially tapered bars.
No full textData and code (as Jupyter notebook) allowing for generating results presented in figures in Michał K. Kalkowski, Jen M. Muggleton, Emiliano Rustighi, An experimental approach for the determination of axial and flexural wavenumbers in circular exponentially tapered bars, Journal of Sound and Vibration, Volume 390, 3 March 2017, Pages 67-85, ISSN 0022-460X, http://dx.doi.org/10.1016/j.jsv.2016.10.018
Work was funded by EPSRC, Assessing the Underworld (EP/K021699/1) </span
Active vibration control of a doubly-curved panel under pressurization
No full textThis study focuses on the control of doubly-curved panels which occur in aircrafts due to the deflection of fuselage panels during lateral pressure loading. This paper describes experimental work conducted toward the implementation of a feedback velocity control system on a pressurised panel of varying curvature in both the x and y directions. A thin rectangular aluminium panel was clamped to an airtight, rigid-walled enclosure and the curvature of the panel was varied through changing the interior static pressure. An electrodynamic proof-mass actuator and collocated accelerometer were implemented on the panel and in order to ensure stability and improve the performance of the feedback controller, a compensation filter was designed and added to the system. The attenuation in the structural response was investigated for increasing curvature. Current offline results show that effective control can be achieved for low levels of curvature. Furthermore, the compensated controller is robust to changes in curvature and the optimal gain of the compensated system remains more or less independent of the curvature level. However, increasing the curvature further causes modal clustering near the panel’s ring frequency which reduces the performance of the controller
Shape of a spectral excitation matrix for a linear road/tyre interaction numerical analysis
No full textTyre/road interaction is recognized as the main source
of interior and exterior noise for velocities over 40 km/h.
The authors have proposed a linear stochastic
approach to predict the tyre vibrations due to the
road/tyre interaction. A mechanical model of the tyre
is connected to the road through a Winkler contact
model with all the springs in the contact patch assumed
to be in contact with the road at all the time. Such a
linear model is strictly valid for smooth road and soft
tyres. In this paper the authors investigate the range
of validity of the linearity assumption and they also
propose a modified shape of the excitation matrix
that takes into account the contact non-linearity. The
investigation is based on a numerical non-linear model
of a 2D tyre. The model consists of a rigid curved body
that touches the road through a Winkler model, in
which the number of the springs in contact and their
actual compression has been found through a quasistatic
equilibrium analysis
A model of tyre vibration with stochastic excitation
No full textFor vehicle at normal driving conditions and speeds above 30-40 km/h the dominating external noise source is the sound generated by the tyre and road interaction. Previous measurements have shown that there is a strong correlation between the radiated sound pressure and the vibrations of the tyre structure for frequency below approximately 1 kHz. The tyre vibration is also the main source of noise inside many vehicles in this frequency range. It is thus important to develop simple tools that predict the tyres behaviour in this frequency range.The tyre is modelled as an elemental system, which permits the analysis of the low frequency tyre response when excited by distributed stochastic forces in the contact patch. Although the contact mechanism is generally non-linear, it is assumed here that the tyre is compliant enough for the whole of the contact patch to remain of the same width and to be always in touch with the road. A linear model can then be used to calculate the contact forces from the road roughness and thus calculate the resulting radial velocity of the tyre. A spectral density matrix, derived from a road roughness model, describes the velocities and is used to calculate the expectation of the tyre’s kinetic energy and its sound power radiation.In the first instance a simple two-dimensional model will be used with a Winkler bedding model of the contact patch to predict the power spectral density of the tyre vibration at different road speeds. This model can also be used to provide an initial estimate of the potential effect of various active control strategies for reducing the tyre vibrations. In particular an optimised feed-forward control formulation can be used to calculate the potential effect of various types of actuators, by calculating the optimal performance with different distributions of secondary force
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