4,423 research outputs found
Positive decaying solutions for differential equations with phi-laplacian
We solve a nonlocal boundary value problem on the half-close interval associated to the differential equation , in the superlinear case . By using a new approach, based on a special energy-type function E, the existence of slowly decaying solutions is examined too
Detection of hidden structures on all scales in amorphous materials and complex physical systems: basic notions and applications to networks, lattice systems, and glasses
Recent decades have seen the discovery of numerous complex materials. At the
root of the complexity underlying many of these materials lies a large number
of possible contending atomic- and larger-scale configurations and the
intricate correlations between their constituents. For a detailed
understanding, there is a need for tools that enable the detection of pertinent
structures on all spatial and temporal scales. Towards this end, we suggest a
new method by invoking ideas from network analysis and information theory. Our
method efficiently identifies basic unit cells and topological defects in
systems with low disorder and may analyze general amorphous structures to
identify candidate natural structures where a clear definition of order is
lacking. This general unbiased detection of physical structure does not require
a guess as to which of the system properties should be deemed as important and
may constitute a natural point of departure for further analysis. The method
applies to both static and dynamic systems.Comment: (23 pages, 9 figures
Production of crystallized fruit from watermelon rind
El presente trabajo tuvo como objetivo el aprovechamiento de las cascaras de sandía en la elaboración de productos cristalizados. Para esto fue eliminada la cutícula verde externa de la cascara, cortadas en forma de cubo de aproximadamente 7 mm de lado, escaldado con agua en su temperatura de ebullición utilizando 0, 5 ó 10 minutos y dejados inmersos en una solución de cloruro de sodio. Posteriormente fueron sometidas a concentraciones crecientes de soluciones de sacarosa (30 a 72 °Brix) y deshidratadas en un secador a diferentes temperaturas (40, 60 y 80 °C). Los diferentes tratamientos fueron evaluados por un panel sensorial. El diseño experimental empleado fue el de bloques completos aleatorios y los resultados del análisis sensorial fueron evaluados por la prueba de comparación de medias de Tukey. Fue constatado que el tratamiento con mayor aceptabilidad, por parte del panel sensorial, fue la que había sido sometida a un escaldado de 5 minutos y deshidratado a 60 °C, cuyos valores de intensidad para la apariencia, sabor y gomosidad estuvieron entre 6 y 7.The aim of this work was to produce crystallized fruit from watermelon rind. The following procedure was developed: the outer peel was removed; the material was sliced into 7 mm cubes, blanched for, 0, 5 and 10 minutes, and then treated with 10% sodium chloride solution. This product was treated with solutions of sucrose (30 to 72 °Brix), and dried in a hot air dryer at different temperatures (40, 60 and 80 °C). Products were then analyzed by a sensory panel. The experimental design used was randomized blocks and the results were analyzed by the Tukey's test. The best acceptance of the sensory panel was for the product obtained by 5 minutes blanching followed by drying at 60 °C, whose intensity values for appearance, flavor and gummosis were between 6 and 7
Three-dimensional through-flow modelling of axial flow compressor rotating stall and surge
This paper presents a three-dimensional through-flow approach based on the cylindrical Euler equations incorporating a body force method. Blade performance is captured through a mixture of empirical correlations and a novel reverse flow treatment. The code is the first application of a physically correct Godunov solver to three-dimensional rotating stall and surge modelling. This solver ensures the accurate calculation of inter-cell fluxes unlike in typical modern CFD codes in which the non-linear convective terms are linearised. Validation consists of modelling a low speed three-stage axial compressor in all operating regions, recreating the reverse flow, rotating stall and forward flow characteristics with good agreement to experimental data. Additional comparisons are made against rotating stall cell size and speed, to which good agreement is also shown. The paper ends with some full surge cycle simulations modifying both the tank volume after the compressor and the level of inlet distortion applied. Both tank volume and level of distortion have been found to affect the type of instability developed. The development of this code is a step forward in compressor rotating stall and reverse flow modelling and allows recreation of a full compressor map at a significantly low computational cost when compared to commercially available 3D CFD codes
Fragile-to-strong transition: a possibly universal feature of metallic glass-forming liquids:A keynote talk
- …