The application of diffraction gratings to solar cells is a promising approach to superseding the light trapping limits of conventional Lambertian structures. In this paper a mathematical formalism is derived for calculating the absorption that can be expected in a solar cell equipped with a diffraction grating, which can be applied to any lattice geometry and grating profile. Furthermore, the formalism is used to calculate the upper limit of total absorption that can theoretically be achieved using a diffraction grating. The derived formalism and limits are valid when the solar cell thickness is greater than the coherence length of the illuminating solar spectrum. Comparison is made to the upper limit achievable using an angularly selective Rugate filter, which is also calculated. Both limits are found to be considerably higher than the Lambertian limit within the range of sunlight concentration factors practically employed in photovoltaic systems (1–1000×). The upper limit of absorption using the diffraction grating is shown to be equal to the thermodynamic limit for all absorbances and concentration factors. The limit for the Rugate filter is generally lower, but tends to the thermodynamic limit for lower cell absorbances. Copyright © 2011 John Wiley {&} Sons, Ltd.

We prove sufficient conditions for the boundedness of the maximal operator on variable Lebesgue spaces with weights \(\varphi_{t,\gamma}(\tau)=|(\tau-t)^\gamma|\), where \(\gamma\) is a complex number, over arbitrary Carleson curves. If the curve has different spirality indices at the point $t$ and \(\gamma\) is not real, then \(\varphi_{t,\gamma}\) is an oscillating weight lying beyond the class of radial oscillating weights considered recently by V. Kokilashvili, N. Samko, and S. Samko.

We prove necessary and sufficient conditions for the applicability of the finite section method to an arbitrary operator in the Banach algebra generated by the operators of multiplication by piecewise continuous functions and the convolution operators with symbols in the algebra generated by piecewise continuous and slowly oscillating Fourier multipliers on \(L^p(\mathbb{R})\), \(1 < p < \infty\).

{We deduce a shallow water model, describing the motion of the fluid in a lake, assuming inflow-outflow effects across the bottom. This model arises from the asymptotic analysis of the 3D dimensional Navier-Stokes equations. We prove the global in time existence result for this model in a bounded domain taking the nonlinear slip/friction boundary conditions to describe the inflows and outflows of the porous coast and the rivers. The solvability is shown in the class of solutions with L(p)-bounded vorticity for any given p is an element of (1, infinity). Copyright (C) 2009 John Wiley & Sons, Ltd.}

The post-graduation in the field of Technology Assessment (TA) is recent and that are several and different ways to be organised. Most experiences are related with the Masters diplom level (2nd cycle of graduation in high education). Just one in PhD level is explicit in the field of TA, and some other PhD courses include also TA topics in their programme structure. In this chapter we will analyse the problems related with the design of a post-graduation (MA, MSc or PhD) programme in the field of TA using as reference some international experiences. Hereby, the main conclusion seems to address labour market needs in the specialised knowledge of TA, of technology management or technology innovation. In this sense TA should be included as “minor” into post-graduation courses which may range from engineering disciplines to social sciences. As a graduation programme it can fill an expertise gap between technicians,engineers, scientists and the strategic decision makers or policy makers.

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This paper addresses the automatic generation of RF integrated inductors model. In this work the double p-model is used as a way of characterizing the inductor behaviour over a frequency range beyond the self-resonant value. For the evaluation of the model element values analytical expressions based on technology parameters as well as on the device geometric characteristics are used. The use of a technology-based methodology for the evaluation of the model parameters grants the adaptability of the models generated to any technology. The inductor analytical characterization is integrated into an optimization-based tool for the automatic design of RF integrated inductors. This tool uses a Genetic Algorithm (GA) optimization procedure, where user defined constraints on the design parameters are taken into account. Due to the design constraints nature and topology constraints, discrete variables optimization techniques are used.

New compounds of the general formulas [M(Ar-BIAN)(2)]BF(4) and [M(Ar-BIAN)(NCMe)(2)]BF(4), where M=Cu(1) or Ag(1) and Ar-BIAN = bis(aryl)acenaphthenequinonediimine, were synthesized by the direct reaction of [Cu(NCMe)(4)]BF(4) or [Ag(NCMe)(4)]BF(4) with the corresponding Ar-BIAN ligand in dried CH(2)Cl(2). The synthesized compounds are [M(o, d, p-Me(3)C(6)H(2)-BIAN)(2)]BF(4) where M = Cu(1) (1) and Ag(1) (2), [M(o,d-iPr(2)C(6)H(3)-BIAN)(NCMe)(2)]BF(4) where M = Cu(1) (3) and Ag(1) (4), and [Ag(o,d-iPr(2)C(6)H(3)-BIAN)(2)]BF(4) (5). The crystal structures of compounds 1-3 and 5 were solved by singlecrystal X-ray diffraction. In all cases copper(I) or silver(I) are in a distorted tetrahedron that is constructed from the four nitrogen atoms of the two a-diimine ligands or, in 3, from one a-diimine ligand and two acetonitrile molecules. All compounds were characterized by elemental analyses, matrix-assisted laser desorption ionization time-of-flight mass spectrometry, and IR, UV-vis, and (1)H NMR spectroscopy. The analysis of the molecular geometry and the energetic changes for the formation reactions of the complexes, in a CH(2)Cl(2) solution, were evaluated by density functional theory calculations and compared with the experimental results.

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