Mood disorders. Prevalence and course of unspecified functional disorders from the epidemiologic and psychosomatic viewpoint

Subjective complaints or somatoform symptoms beyond the case threshold (ICD-diagnoses) occur in 12% of the normal population. In recent studies prevalence is at least 17% in primary care. Somatoform complaints (e.g. headache with 38.7%) or non-specific common symptoms (e.g. feeling of inner restlessness with 41.3%) are much more widespread. Mostly, several symptoms together are forming a multiple somatoform syndrome. As well known from other psychogenic disorders, spontaneous long-term course of somatoform symptoms is variable due to the psychic co-morbidity (in particular anxiety and depression) and a strong tendency to symptomatic shift. The long-term course of total impairment by additional psychogenic symptoms is rather bad in somatoform disorders. Clinically significant personality traits and traumatic influences during early childhood development are correlated with somatoform disorders. Within the traditional role patterns of the relation between physician and patient, somatoform complaints often communicate or indicate a psychodynamic conflict. In this case, a psychosomatic/psychotherapeutic approach in primary care or a specialized psychotherapy is indicated.     

Thermodynamic Activities in B2O3-SiO2 Melts at 1475 K

Eight glass samples in the B₂O₃-SiO₂ system with compositions from 20 to 90 mol% B₂O₃ were prepared. The equilibrium vaporization was studied by Knudsen effusion mass spectrometry at temperatures between 1450 and 1500 K. B₂O₃ ( g ) was the most abundant boron-containing species in the vapor; no silicon-containing gaseous species were detected. Thermodynamic activities of B₂O₃ in the liquid were determined at 1475 K. Thermodynamic activities of SiO₂ and integral excess Gibbs energies were estimated from the thermodynamic activities of B₂O₃. The thermodynamic data support the results obtained by other methods indicating the existance of a miscibility gap in the metastable liquid.     

High-temperature low-friction properties of vanadium-alloyed AlCrN coatings

V-alloyed AlCrN hard coatings were deposited by reactive arc-evaporation in a commercial Balzers RCS coating system. The Al/(Al + Cr + V) atomic ratio in the target was kept constant at 0.7, while the Cr was stepwise substituted by V. Alloying V into the AlCrN coatings led to the partial transformation to a hexagonal phase of the otherwise metastable cubic lattice, whereas the hexagonal phase fraction was observed to increase with the V concentration in the coating. This results in a reduction of hardness (from 28 to 19 GPa) and biaxial coating stress (from − 1700 to − 900 MPa). The performed tribological tests at high temperature revealed a significantly lower coefficient of friction down to a value of 0.2 for Al_0.67Cr_0.05V_0.28N at 700 °C. This behaviour is due to the formation and melting of the Magnéli phase oxide V₂O₅ forming a low-friction layer on the surface as indicated by Raman spectroscopy and scanning electron microscopy.     

Analyses of the aqueous phase during early C3S hydration

The concentrations of calcium and silica in solution during the first 4 hours of C₃S hydration were measured. The results of these analyses indicate that a solid calcium silicate hydrate forms within 30 seconds of the start of hydration and that an equilibrium between the solution and the solid hydrate is rapidly established. A strong dependence of the rate of early hydration on the w:C₃S ratio was observed, while the dependence on the surface area of the C₃S was minimal.     

Winglet optimization for a model‐scale wind turbine

A winglet optimization method is developed and tested for a model‐scale wind turbine. The best‐performing winglet shape is obtained by constructing a Kriging surrogate model, which is refined using an infill criterion based on expected improvement. The turbine performance is simulated by solving the incompressible Navier‐Stokes equations, and the turbulent flow is predicted using the Spalart‐Allmaras turbulence model. To validate the simulated performance, experiments are performed in the Norwegian University of Science and Technology wind tunnel. According to the simulations, the optimized winglet increases the turbine power and thrust by 7.8% and 6.3%, respectively. The wind tunnel experiments show that the turbine power increases by 8.9%, while the thrust increases by 7.4%. When introducing more turbulence in the wind tunnel to reduce laminar separation, the turbine power and thrust due to the winglet increases by 10.3% and 14.9%, respectively.     

Combined radiation and convection heat transfer in a porous channel bounded by isothermal parallel plates

Combined radiation and convection heat transfer in a porous medium confined between gray isothermal parallel plates is investigated. The medium is absorbing, emitting and scattering. Cases of boundaries at temperatures higher or lower than the medium are considered. In the porous medium, the boundary effect on the fully developed laminar velocity field as proposed by Kaviany is accounted for. For various values of the extinction coefficient, the scattering albedo, the conduction-radiation parameter and the boundary emissivity, Nusselt number, temperature and heat flux distributions are found for the range of values including the extreme limits of the porous medium shape parameter (PMSP), γ=(W²φ/K)^1/2, where W is the channel width, φ the porosity and K the permeability. For the lower limiting value of the PMSP γ, the effect of the porous medium is negligible and the situation approaches that of Poiseuille flow. For this limiting case, results from the present work are compared with those available in the literature. For medium to high values of the PMSP γ, for the purpose of comparison, some results are presented in tabular form. Radiation is found to have a significant effect on various parameters studied. The discrete transfer method was used for the solution of the radiative part of the energy equation. An iterative finite difference scheme was used to solve the energy equation.     

FFTs with Near-Optimal Memory Access Through Block Data Layouts: Algorithm,Architecture and Design Automation

Fast Fourier transform algorithms on large data sets achieve poor performance on various platforms because of the inefficient strided memory access patterns. These inefficient access patterns need to be reshaped to achieve high performance implementations. In this paper we formally restructure 1D, 2D and 3D FFTs targeting a generic machine model with a two-level memory hierarchy requiring block data transfers, and derive memory access pattern efficient algorithms using custom block data layouts. These algorithms need to be carefully mapped to the targeted platform’s architecture, particularly the memory subsystem, to fully utilize performance and energy efficiency potentials. Using the Kronecker product formalism, we integrate our optimizations into Spiral framework and evaluate a family of DRAM-optimized FFT algorithms and their hardware implementation design space via automated techniques. In our evaluations, we demonstrate DRAM-optimized accelerator designs over a large tradeoff space given various problem (single/double precision 1D, 2D and 3D FFTs) and hardware platform (off-chip DRAM, 3D-stacked DRAM, ASIC, FPGA, etc.) parameters. We show that Spiral generated pareto optimal designs can achieve close to theoretical peak performance of the targeted platform offering 6x and 6.5x system performance and power efficiency improvements respectively over conventional row-column FFT algorithms.