Equilibrium of a Brownian particle with coordinate dependent diffusivity and damping: Generalized Boltzmann distribution

Fick's law for coordinate dependent diffusivity is derived. Corresponding diffusion current in the presence of coordinate dependent diffusivity is consistent with the form as given by Kramers-Moyal expansion. We have obtained the equilibrium solution of the corresponding Smoluchowski equation. The equilibrium distribution is a generalization of the Boltzmann distribution. This generalized Boltzmann distribution involves an effective potential which is a function of coordinate dependent diffusivity. We discuss various implications of the existence of this generalized Boltzmann distribution for equilibrium of systems with coordinate dependent diffusivity and damping.Comment: 11 pages, 1 figur

Development of parsing tools for Casl using generic language technology

An environment for the Common Algebraic Specification Language CASL consists of independent tools. A number of CASL have been built using the algebraic formalism ASF+SDF and the+SDF Meta-Environment. CASL supports-defined syntax which is non-trivial to: ASF+SDF offers a powerful parsing(Generalized LR). Its interactive environment facilitates rapid complemented by early detection correction of errors. A number of core developed for the ASF+SDF-Environment can be reused in the context CASL. Furthermore, an instantiation of a format developed for the representation ASF+SDF specifications and terms provides a-specific exchange format

Quantitative magneto-optical investigation of superconductor/ferromagnet hybrid structures

We present a detailed quantitative magneto-optical imaging study of several superconductor/ferromagnet hybrid structures, including Nb deposited on top of thermomagnetically patterned NdFeB, and permalloy/niobium with erasable and tailored magnetic landscapes imprinted in the permalloy layer. The magneto-optical imaging data is complemented with and compared to scanning Hall probe microscopy measurements. Comprehensive protocols have been developed for calibrating, testing, and converting Faraday rotation data to magnetic field maps. Applied to the acquired data, they reveal the comparatively weaker magnetic response of the superconductor from the background of larger fields and field gradients generated by the magnetic layer.Comment: 21 pages, including 2 pages of supplementary materia

Balancing between coordination, cooperation and competition? A mixed-method approach for assessing the role ambiguity of local sports authorities

In recent years, the subsidiarity principle has been underlined in Sport-for-All policies in countries such as Germany, Austria and Belgium. According to this organising principle, issues need to be handled by the lowest possible political and administrative level, and as close to the citizens as possible. The 2007 decree concerning Sport-for-All policies at the local level in Flanders (Belgium) clearly referred to this. It emphasised the decentralisation of the Sport for All policy, and highlighted the regulatory and coordinating role of local sports authorities. As a consequence, they may face conflicting roles of being coordinator, regulator and provider of mass sport at the local level. In this paper, a mixed-method approach is used to give a closer insight in the role perceptions of local sports authorities in Flanders, and their position towards private sport providers. The results show that local sports authorities consider the coordination and regulation of mass sport in their municipality as their primary task. Yet, it appears that private sport providers also perceive competition from local sports authorities. Moreover, a considerable number of the local sports authorities believe they can combine the roles of provider and coordinator. As there appears to be considerable goal ambiguity, it is necessary for local sports authorities to formulate clear goals. Referring to the principle of subsidiarity, it is argued that sports authorities should only intervene when (non-)profit sport providers are not able to achieve the desirable outcomes with regard to sport and the welfare agenda

ASKyphoplan: a program for deformity planning in ankylosing spondylitis

A closing wedge osteotomy of the lumbar spine may be considered to correct posture and spinal balance in progressive thoracolumbar kyphotic deformity caused by ankylosing spondylitis (AS). Adequate deformity planning is essential for reliable prediction of the effect of surgical correction of the spine on the sagittal balance and horizontal gaze of the patient. The effect of a spinal osteotomy on the horizontal gaze is equal to the osteotomy angle. However, the effect of a spinal osteotomy on the sagittal balance depends on both the correction angle and the level of osteotomy simultaneously. The relation between the correction angle, the level of osteotomy and the sagittal balance of the spine can be expressed by a mathematical equation. However, this mathematical equation is not easily used in daily practice. We present the computer program ASKyphoplan that analyses and visualizes the planning procedure for sagittal plane corrective osteotomies of the spine in AS. The relationship between the planned correction angle, level of osteotomy and sagittal balance are coupled into the program. The steps taken during an ASKyphoplan run are outlined, and the clinical application is discussed. The application of the program is illustrated by the analysis of the data from a patient recently treated by a lumbar osteotomy in AS. The software can be used free of charge on the internet at http://www.stega.nl under the heading “research” in the menu