Efficient Adaptive Stochastic Collocation Strategies for Advection-Diffusion Problems with Uncertain Inputs

Physical models with uncertain inputs are commonly represented as parametric partial differential equations (PDEs). That is, PDEs with inputs that are expressed as functions of parameters with an associated probability distribution. Developing efficient and accurate solution strategies that account for errors on the space, time and parameter domains simultaneously is highly challenging. Indeed, it is well known that standard polynomial-based approximations on the parameter domain can incur errors that grow in time. In this work, we focus on advection-diffusion problems with parameter-dependent wind fields. A novel adaptive solution strategy is proposed that allows users to combine stochastic collocation on the parameter domain with off-the-shelf adaptive timestepping algorithms with local error control. This is a non-intrusive strategy that builds a polynomial-based surrogate that is adapted sequentially in time. The algorithm is driven by a so-called hierarchical estimator for the parametric error and balances this against an estimate for the global timestepping error which is derived from a scaling argument.Comment: 29 pages, 14 figure

Dominant mutations in the cation channel gene transient receptor potential vanilloid 4 cause an unusual spectrum of neuropathies

Hereditary neuropathies form a heterogeneous group of disorders for which over 40 causal genes have been identified to date. Recently, dominant mutations in the transient receptor potential vanilloid 4 gene were found to be associated with three distinct neuromuscular phenotypes: hereditary motor and sensory neuropathy 2C, scapuloperoneal spinal muscular atrophy and congenital distal spinal muscular atrophy. Transient receptor potential vanilloid 4 encodes a cation channel previously implicated in several types of dominantly inherited bone dysplasia syndromes. We performed DNA sequencing of the coding regions of transient receptor potential vanilloid 4 in a cohort of 145 patients with various types of hereditary neuropathy and identified five different heterozygous missense mutations in eight unrelated families. One mutation arose de novo in an isolated patient, and the remainder segregated in families. Two of the mutations were recurrent in unrelated families. Four mutations in transient receptor potential vanilloid 4 targeted conserved arginine residues in the ankyrin repeat domain, which is believed to be important in protein-protein interactions. Striking phenotypic variability between and within families was observed. The majority of patients displayed a predominantly, or pure, motor neuropathy with axonal characteristics observed on electrophysiological testing. The age of onset varied widely, ranging from congenital to late adulthood onset. Various combinations of additional features were present in most patients including vocal fold paralysis, scapular weakness, contractures and hearing loss. We identified six asymptomatic mutation carriers, indicating reduced penetrance of the transient receptor potential vanilloid 4 defects. This finding is relatively unusual in the context of hereditary neuropathies and has important implications for diagnostic testing and genetic counsellin

Machine and equipment monitoring, automation of technological processes in longwall and roadheading systems

Gromadzenie informacji dotyczących aktualnego przebiegu produkcji w sposób przejrzysty i ogólnie dostępny a także nadzór nad stanem pracy urządzeń produkcyjnych, nad maszynami i urządzeniami elektroenergetycznymi czy instalacjami przemysłowymi nadawy urobku na jednym stanowisku np. dyspozytora energomaszynowego w zakładzie pracy był i jest trendem wielu zakładów przemysłowych, także górniczych. Nadzorowanie maszyn jak i dostosowywanie ich parametrów poprzez szeroko rozumianą wizualizację w zmieniającym się środowisku ich pracy, to główny cel służb energomaszynowych a także geologicznych czy tąpań. Szczególnym problemem jest eksploatacja w bardzo trudnych warunkach i w strefach szczególnego zagrożenia.Information gathering concerning current production process in a clear and widely available manner as well as supervision of the operating status of the production equipment; machines and electrical power devices or manufacturing installation of mine output feed on one job position, e.g. of mechanical and electrical equipment dispatcher in the work place was and still is the trend in many plants, mining as well. Supervision of the machines and adjusting its parameters through visualization in a broad sense in its changing working environment is the main goal of the electrical and mechanical service as well as geological or rockburst too. There is a special problem in exploitation in very difficult conditions and danger zones