Conversazione con Omar Calabrese su Matthew Barney e il neobarocco

Nell’intervista Omar Calabrese riconosce in quella di Barney “un’opera tipicamente neobarocca realizzata con mezzi contemporanei” e discute delle ideologie e dei meccanismi di costruzione della star sottese al suo lavoro. Secondo Calabrese, l’operazione di Barney è quella di un “azzeramento” e di una “dissoluzione” dell’opera secondo la vecchia architettura e la vecchia concezione per riformulare, in modo sempre autoriflessivo, la storia dell’art

Lumped mass modelling for the dynamic analysis of aircraft structures

Aircraft structures may be modelled by lumping the masses at particular strategic points and the flexibility or stiffness of the structure is obtained with reference to these points. Equivalent moments of inertia for the section at these positions are determined. The lumped masses are calculated based on the assumption that each point will represent the mass spread on one half of the space on each side. Then these parameters are used in the differential equation of motion and the eigen characteristics are determined. A comparison is made with results obtained by other established methods. The lumped mass approach in the dynamic analysis of complicated structures provides an easier means of predicting the dynamic characteristics of these structures. It involves less computer time and avoids computational errors that are inherent in the numerical solution of complicated systems

Remote Sensing of the Ocean Environment Using Finite Element Methods

Oceans are a vast, complex world where underwater sound is the most efficient tool available to understand its detailed characteristics. However the underwater channel has a very complex geometrical and material structure and hence special techniques are required to model it. Analytical solutions are feasible only when one makes gross assumptions and approximations. Several numerical and semi-numerical techniques have been developed for estimating the sound field in the ocean channel. But no single method is capable of handling all possible environmental conditions, frequency, and ranges of interest in remote sensing problems. We explore in this chapter the scope and feasibility of finite element method in underwater remote sensing. The current study is based on a channel model with cylindrical symmetry and a time-harmonic source signal. A variational formulation is used to derive the finite element model for acoustical radiation, scattering and propagation in the ocean. A Bayliss-type radiation boundary condition is used to model the far field behaviour without the need to deal with a large solution domain. Since the ocean geometry can support several propagating, evanescent, and radiation modes, a penalty function approach is employed to impose the far field radiation condition. A distinct feature of the ocean channel is its depth-dependent sound speed. The eigensolution for this channel is required for imposing the radiation condition at the truncation boundary. We have cast this eigenproblem in a variational form and employed a Rayleigh-Ritz method to obtain an approximate eigensolution. This approach has provided a good approximation of the depth eigenmodes in a compact semi-analytic form. We have employed our finite element algorithm to model several range- and depth-dependent ocean problems. Our numerical study has established that our finite element algorithm gives accurate results with reasonable effort. In particular, our finite element approach is most appropriate for shallow water problems where the interaction of wave modes with irregular ocean bottom is quite complex. The penalty function approach employed to implement the radiation boundary condition has been found to be robust over a wide range of penalty scale factors. We have also extended this work for the case of irregular elastic sea bed. We continue to explore and further develop our finite element approach by applying it to several other ocean acoustic problems encountered in the remote sensing of ocean environment

Quantum reflection of atoms from a solid surface at normal incidence

We observed quantum reflection of ultracold atoms from the attractive potential of a solid surface. Extremely dilute Bose-Einstein condensates of ^{23}Na, with peak density 10^{11}-10^{12}atoms/cm^3, confined in a weak gravito-magnetic trap were normally incident on a silicon surface. Reflection probabilities of up to 20 % were observed for incident velocities of 1-8 mm/s. The velocity dependence agrees qualitatively with the prediction for quantum reflection from the attractive Casimir-Polder potential. Atoms confined in a harmonic trap divided in half by a solid surface exhibited extended lifetime due to quantum reflection from the surface, implying a reflection probability above 50 %.Comment: To appear in Phys. Rev. Lett. (December 2004)5 pages, 4 figure

Data indexing techniques for the EUVE all-sky survey

This poster describes techniques developed for manipulating large full-sky data sets for the Extreme Ultraviolet Explorer project. The authors have adapted the quatrilateralized cubic sphere indexing algorithm to allow us to efficiently store and process several types of large data sets, such as full-sky maps of photon counts, exposure time, and count rates. A variation of this scheme is used to index sparser data such as individual photon events and viewing times for selected areas of the sky, which are eventually used to create EUVE source catalogs

Evaluation of a flipped examination model implemented in a final-year undergraduate pharmacotherapeutics course

© 2019, American Association of Colleges of Pharmacy. All rights reserved. Objective. To assess final-year pharmacy students’ performance on and evaluate their experience with a “flipped examination” vs a traditional examination for an advanced clinical pharmacy course. Methods. Students devised multiple-choice questions for the flipped examination. The Biggs revised 2-factor Study Process Questionnaire was administered before and after the examination to assess any possible changes in the students’ perceptions of their level of engagement in the learning process. Focus group discussions also were conducted to further gauge the students’ feedback and insights into the flipped examination experience. Results. Changes in mean total study process scores at the deep and surface levels of learning were significant. The flipped examination experience was enjoyable, facilitated a less-stressful learning environment, and improved the students’ learning satisfaction, knowledge, and assessment grades. Conclusion. The flipped examination model is an innovative instructional approach that can bring about significant educational gains if designed well pedagogically