Effects of the economic - financial crisis on regional development in post-accession Romania

To apply the regional development policy of the European Union in Romania, eight development regions have been established, regions that are not administrative - territorial units wthout legal personality and which are eligible for funding from the EU Structural Funds. In the current world of circumstances, in Romania there is a trend of increasing regional disparity. The National Development Plan (2007-2013) sets out the overall aim of reducing the swift socio-economic disparity between Romania and the other EU countries

Development of portable microfading spectrometers for measurement of light sensitivity of materials

Microfading was originally designed for efficiently detecting extremely light-sensitive materials on objects in situ to determine the appropriate exhibition lighting conditions. By focusing an intense beam of light to a tiny submillimetre sized spot and simultaeously monitoring the colour change over time, the fading rate of the material can be measured without producing noticeable damage. The increased intensity of light allows rapid determination of light-fastness of materials. This paper examines an improved design of microfading spectrometer that is easy to assemble, compact, robust, capable of fully automatic acquisition of data with precision control of the fading time to produce higher precision measurements and to allow simultaneous monitoring of colour, spectral reflectance and other changes in real time. The effects of various parameters such as thickness and concentration of paint layer, the binding medium and substrate on the fading rates are examined for selected pigments and found that in certain cases substrates, binding media and thickness can affect the fading rate. Reciprocity in the context of microfading compared with realistic exhibition conditions is examined and found that it breaks down for some pigment

SBML Level 3 Package Specification: Hierarchical Model Composition, Version 1 Draft

In the context of SBML, “hierarchical model composition” refers to the ability to include models as submodels inside another model. The goal is to support the ability of modelers and software tools to do such things as (1) decompose larger models into smaller ones, as a way to manage complexity; (2) incorporate multiple instances of a given model within one or more enclosing models, to avoid literal duplication of repeated elements; and (3) create libraries of reusable, tested models, much as is done in software development and other engineering fields

SBML Level 3 package: Groups, Version 1 Release 1

Biological models often contain components that have relationships with each other, or that modelers want to treat as belonging to groups with common characteristics or shared metadata. The SBML Level 3 Version 1 Core specification does not provide an explicit mechanism for expressing such relationships, but it does provide a mechanism for SBML packages to extend the Core specification and add additional syntactical constructs. The SBML Groups package for SBML Level 3 adds the necessary features to SBML to allow grouping of model components to be expressed. Such groups do not affect the mathematical interpretation of a model, but they do provide a way to add information that can be useful for modelers and software tools. The SBML Groups package enables a modeler to include definitions of groups and nested groups, each of which may be annotated to convey why that group was created, and what it represents

Dimensional crossover of the exchange-correlation energy at the semilocal level

Commonly used semilocal density functional approximations for the exchange-correlation energy fail badly when the true two dimensional limit is approached. We show, using a quasi-two-dimensional uniform electron gas in the infinite barrier model, that the semilocal level can correctly recover the exchange-correlation energy of the two-dimensional uniform electron gas. We derive new exact constraints at the semilocal level for the dimensional crossover of the exchange-correlation energy and we propose a method to incorporate them in any exchange-correlation density functional approximation.Comment: 6 pages, 5 figure

Wavevector analysis of the jellium exchange-correlation surface energy in the random-phase approximation: detailed support for nonempirical density functionals

We report the first three-dimensional wavevector analysis of the jellium exchange-correlation (xc) surface energy in the random-phase approximation (RPA). The RPA accurately describes long-range xc effects which are challenging for semi-local approximations, since it includes the universal small-wavevector behavior derived by Langreth and Perdew. We use these rigorous RPA calculations for jellium slabs to test RPA versions of nonempirical semi-local density-functional approximations for the xc energy. The local spin density approximation (LSDA) displays cancelling errors in the small and intermediate wavevector regions. The PBE GGA improves the analysis for intermediate wavevectors, but remains too low for small wavevectors (implying too-low jellium xc surface energies). The nonempirical meta-generalized gradient approximation of Tao, Perdew, Staroverov, and Scuseria (TPSS meta-GGA) gives a realistic wavevector analysis, even for small wavevectors or long-range effects. We also study the effects of slab thickness and of short-range corrections to RPA.Comment: 7 pages, 7 figures, to appear in Phys. Rev.

Proximity effect in clean strong/weak/strong superconducting tri-layers

Recent measurements of the Josephson critical current through LSCO/LCO/LSCO thin films showed an unusually large proximity effect. Using the Bogoliubov-de Gennes (BdG) equations for a tight binding Hamiltonian we describe the proximity effect in weak links between a superconductor with critical temperature $T_c$ and one with critical temperature $T_c$', where $T_c>T_c$'. The weak link (N') is therefore a superconductor above its own critical temperature and the superconducting regions are considered to have either s-wave or d-wave symmetry. We note that the proximity effect is enhanced due to the presence of superconducting correlations in the weak link. The dc Josephson current is calculated, and we obtain a non-zero value for temperatures greater than $T_c$' for sizes of the weak links that can be almost an order of magnitude greater than the conventional coherence length. Considering pockets of superconductivity in the N' layer, we show that this can lead to an even larger effect on the Josephson critical current by effectively shortening the weak link.Comment: submitted to Physical Review

High-Level Correlated Approach to the Jellium Surface Energy, Without Uniform-Electron-Gas Input

We resolve the long-standing controversy over the surface energy of simple metals: Density functional methods that require uniform-electron-gas input agree with each other at many levels of sophistication, but not with high-level correlated calculations like Fermi Hypernetted Chain and Diffusion Monte Carlo (DMC) that predict the uniform-gas correlation energy. Here we apply a very high-level correlated approach, the inhomogeneous Singwi-Tosi-Land-Sj\"olander (ISTLS) method, and find that the density functionals are indeed reliable (because the surface energy is "bulk-like"). ISTLS values are close to recently-revised DMC values. Our work also vindicates the previously-disputed use of uniform-gas-based nonlocal kernels in time-dependent density functional theory.Comment: 4 pages, 1 figur