A CPU–GPU framework for optimizing the quality of large meshes

The automatic generation of 3D finite element meshes (FEM) is still a bottleneck for the simulation of large fluid dynamic problems. Although today there are several algorithms that can generate good meshes without user intervention, in cases where the geometry changes during the calculation and thousands of meshes must be constructed, the computational cost of this process can exceed the cost of the FEM. There has been a lot of work in FEM parallelization and the algorithms work well in different parallel architectures, but at present there has not been much success in the parallelization of mesh generation methods. This paper will present a massive parallelization scheme for re-meshing with tetrahedral elements using the local modification algorithm. This method is frequently used to improve the quality of elements once the mesh has been generated, but we will show it can also be applied as a regeneration process, starting with the distorted and invalid mesh of the previous step. The parallelization is carried out using OpenCL and OpenMP in order to test the method in a multiple CPU architecture and also in Graphics Processing Units (GPUs). Finally we present the speedup and quality results obtained in meshes with hundreds of thousands of elements and different parallel APIs.     

Superlattices as Characterisation Tool for the Beginning of PS Formation

Initial stage of porous silicon (PS) formation has been studied in an original way. Multilayer structures constituting of very thin layers of low porosity and thick layers of high porosity have been fabricated and characterised by optical tools and electron microscopy. The non linear behaviour resulting in a change in the dissolution velocity has been quantified by using a stack layer structure. Finally using thermal oxidation it has been shown that, due to the selective oxidation as a function of the porosity, porous silicon can be used to produce a Si/SiO₂ like structure.     

Medium term market perspectives,goal prices and competitiveness of renewable resources in the Italian energy system

Using a multiperiodal LP model (MARKAL) the authors assessed the likely potential of solar thermal and biogas systems under various circumstances. The study covered the period 1980–2005, in five segments of five years. It focused only on the subsystem of the energy end-uses which can be substituted for by solar and biogas technologies. In this paper we show the main results of the study regarding the competitiveness of the single solar and biogas technologies in different scenarios and their sensitivity to incentives and prices, together with the essential technical data regarding demand and supply technologies which produced those results. The analysis performed of the potential penetration of renewable technologies into the Italian energy system shows that their contribution will remain very marginal if the price of conventional energy carriers remains constant in constant money. However, the objective of removing with renewable technologies 1.5 per cent of the total Italian energy consumption appears to be realistic in the short-medium term.     

Public-Key Encryption Based on Chebyshev Polynomials

We propose public-key encryption algorithms based on Chebyshev polynomials, which are secure, practical, and can be used for both encryption and digital signature. Software implementation and properties of the algorithms are discussed in detail. We show that our ElGamal-like and RSA-like algorithms (when Chebyshev polynomials are employed) are as secure as the original ElGamal and RSA algorithms.     

Farm Animal Serum Proteomics and Impact on Human Health

Due to the incompleteness of animal genome sequencing, the analysis and characterization of serum proteomes of most farm animals are still in their infancy, compared to the already well-documented human serum proteome. This review focuses on the implications of the farm animal serum proteomics in order to identify novel biomarkers for animal welfare, early diagnosis, prognosis and monitoring of infectious disease treatment, and develop new vaccines, aiming at determining the reciprocal benefits for humans and animals.     

Mechanical and Electrical Properties of Cryo-worked Cu

For manufacturing the magnets of fusion machines pure copper of both high mechanical resistance and electrical conductivity is required. Though high purity copper guarantees high electrical conductivity, its mechanical properties may be not suitable for the applications in tokamaks. In this view, a new procedure developed for obtaining high purity copper with excellent mechanical strength is described in this work. Samples of oxygen free copper (OFC) have been worked by pressing in liquid nitrogen (77 K). It has been verified that the mechanical properties of the worked metal are strongly dependent on the strain rate. Very low strain rates permitted to attain values of tensile yield strength (550 MPa) significantly higher than those obtained by traditional cold-working at room temperature (450 MPa). The electrical conductivity of the cryo-worked Cu decreases with the tensile yield strength even though the hardest samples of tensile yield strength of 550 MPa exhibit still acceptable values of conductivity (about 94 % IACS at room temperature).