Effects of complementary grazing by goats on sward composition and on sheep performance managed during lactation in perennial ryegrass and white clover pastures

The liveweight (LW) response of Gallega and Lacha ewes with their single suckling lambs when grazing with a mob of goats on perennial ryegrass (Lolium perenne L.)/white clover (Trifolium repens L.) pastures and its consequence on sward composition were analysed. From early March (turnout) to mid-June (lamb weaning), swards were grazed either simultaneously mixed in a 1:1 goat to sheep ratio or separately in a goat-first and sheep-last sequential grazing at 6 or 8 cm sward heights or in a 4-paddock rotation where goats grazed swards from 9 to 7 cm followed by sheep from 7 to 4 cm. Changes in botanical composition and in sheep liveweight performance were more significantly affected by the management and species grazing than by the sward height treatment. Swards where goats were last in had higher herbage masses, higher live clover and lower dead and stem proportions than swards where sheep and goats were mixed or sheep were last in. As a consequence of a sward clover enhancement over all treatments, ewe and lamb performances were benefited especially in the Lacha genotype, with the rotational and sequential managements having, respectively, an output of 298 and 252 kg LW/ha greater than the mixed management. These results suggest that goats could be used as a pasture management tool when integrated with sheep under these different grazing systems to enhance ovine performance during lactation

The use of BIM technology in teaching related to Architecture: cooperative and collaborative learning based on real Projects between different subjects

In this article, it is presented the experience of the Educational Innovation Project accepted by the Basque Country University, which is being developed since 2014 at the Polytechnic University School in Donostia. This project highlights for being the first teaching experience in the Technical Architecture Degree, where teams of teachers from different subjects are developing a work in a cooperative, joint, coordinated and collaborative way, and encompassing the full spectrum of the design - construction process closely with the architecture professional dynamics. BIM technology (Building Information Modeling) is being used so that the same three-dimensional parametric modeling is shared among different subjects, for the resolution of real Learning Based Projects, linking teaching and labor market.En esta comunicación, se presenta la experiencia del Proyecto de Innovación Educativa aceptado por la Universidad del País Vasco, que se está desarrollando desde 2014 en la Escuela Universitaria Politécnica de Donostia. Destaca por ser la primera experiencia docente en el Grado en Arquitectura Técnica, donde equipos docentes de diversas materias están desarrollando un trabajo de manera cooperativa, conjunta, coordinada y colaborativa, abarcando el espectro completo del proceso proyectual-constructivo en estrecha relación con la dinámica profesional Arquitectónica. Se está empleando la tecnología BIM, (Building Information Modeling) de manera que se comparte un mismo modelado tridimensional paramétrico entre diferentes asignaturas, para la resolución del Aprendizaje Basado en Proyectos reales, enlazando docencia y mercado laboral

Characterization of Nonlinear Finger Pad Mechanics for Tactile Rendering

The computation of skin forces and deformations for tactile rendering requires an accurate model of the extremely nonlinear behavior of the skin. In this work, we investigate the characterization of finger mechanics with the goal of designing accurate nonlinear models for tactile rendering. First, we describe a measurement setup that enables the acquisition of contact force and contact area in the context of controlled finger indentation experiments. Second, we describe an optimization procedure that estimates the parameters of strain-limiting deformation models that match best the acquired data. We show that the acquisition setup allows the measurement of force and area information with high repeatability, and the estimation method reaches nonlinear models that match the measured data with high accuracy

Anisotropic Strain Limiting

Many materials exhibit a highly nonlinear elastic behavior, such as textiles or finger flesh. An efficient way of enforcing the nonlinearity of these materials is through strain-limiting constraints, which is often the model of choice in computer graphics. Strain-limiting allows to model highly non-linear stiff materials by eliminating degrees of freedom from the computations and by enforcing a set of constraints. However, many nonlinear elastic materials, such as composites, wood or flesh, exhibit anisotropic behaviors, with different material responses depending on the deformation direction. This anisotropic behavior has not been addressed in the past in the context of strain limiting, and naïve approaches, such as applying a different constraint on each component of the principal axes of deformation, produce unrealistic results. In this paper, we enable anisotropic behaviors when using strain-limiting constraints to model nonlinear elastic materials. We compute the limits for each principal axis of deformation through the rotation and hyperbolic projection of the deformation limits defined in the global reference frame. The limits are used to formulate the strain-limiting constraints, which are then seamlessly combined with frictional contact constraints in a standard constrained dynamics solver. Categories and Subject Descriptors (according to ACM CCS): modeling

Multi-resolution isotropic strain limiting

In this paper we describe a fast strain-limiting method that allows stiff, incompliant materials to be simulated efficiently. Unlike prior approaches, which act on springs or individual strain components, this method acts on the strain tensors in a coordinate-invariant fashion allowing isotropic behavior. Our method applies to both two-and three-dimensional strains, and only requires computing the singular value decomposition of the deformation gradient, either a small 2x2 or 3x3 matrix, for each element. We demonstrate its use with triangular and tetrahedral linear-basis elements. For triangulated surfaces in three-dimensional space, we also describe a complementary edge-angle-limiting method to limit out-of-plane bending. All of the limits are enforced through an iterative, non-linear, Gauss-Seidel-like constraint procedure. To accelerate convergence, we propose a novel multi-resolution algorithm that enforces fitted limits at each level of a non-conforming hierarchy. Compared with other constraint-based techniques, our isotropic multi-resolution strain-limiting method is straightforward to implement, efficient to use, and applicable to a wide range of shell and solid materials. © 2010 ACM

Thermal-nanoimprint lithography for perylenediimide-based distributed feedback laser fabrication

In the present work thermal-nanoimprint lithography of various commercial thermoplastic resists as matrixes for perylenediimides (PDIs) has been studied. This fabrication method reduces the number of fabrication steps, and therefore, the cost of the obtained distributed feedback (DFB) lasers. The optical properties of these devices are analyzed, aiming to optimize their performance.Spanish Government (MINECO) and the European Community (FEDER) through grants MAT2008-06648-C02 and MAT-2011-28167-C02. Manuel G. Ramírez is supported by a CSIC fellowship within the program JAE