Outer layer turbulence intensities in smooth- and rough-wall boundary layers

Clear differences in turbulence intensity profiles in smooth, transitional and fully rough zero-pressure-gradient boundary layers are demonstrated, using the diagnostic plot introduced by Alfredsson, Segalini & Örlü (Phys. Fluids, vol. 23, 2011, p. 041702) – u?/U versus U/Ue, where u? and U are the local (root mean square) fluctuating and mean velocities and Ue is the free stream velocity. A wide range of published data are considered and all zero-pressure-gradient boundary layers yield outer flow u?/U values that are roughly linearly related to U/Ue, just as for smooth walls, but with a significantly higher slope which is completely independent of the roughness morphology. The difference in slope is due largely to the influence of the roughness parameter (?U+ in the usual notation) and all the data can be fitted empirically by using a modified form of the scaling, dependent only on ?U/Ue. The turbulence intensity, at a location in the outer layer where U/Ue is fixed, rises monotonically with increasing ?U/Ue which, however, remains of O(1) for all possible zero-pressure-gradient rough-wall boundary layers even at the highest Reynolds numbers. A measurement of intensity at a point in the outer region of the boundary layer can provide an indication of whether the surface is aerodynamically fully rough, without having to determine the surface stress or effective roughness height. Discussion of the implication for smooth/rough flow universality of differences in outer-layer mean velocity wake strength is include

Quantum mechanical scattering investigation of the thermionic and field induced emission components of the dark current in quantum well infrared photodetectors

The thermionic emission and field induced emission components of the dark current in quantum well infrared photodetectors are investigated using a quantum mechanical scattering theory approach. Calculations are performed for an experimentally reported device. Using this as a standard, the device dimensions were altered in order to increase its detection wavelength to cover the mid- (MIR) and far-infrared (FIR) regions of the spectrum. The behavior of the scattering mechanisms that contribute to the thermionic emission and field induced emission components were studied. The results highlight the change in the dominating scattering mediator across the MIR and FIR bands. © 2002 American Institute of Physics

Mapping the dominant regions of the phase space associated with ccˉc \bar c production relevant for the Prompt Atmospheric Neutrino Flux

We present a detailed mapping of the dominant kinematical domains contributing to the prompt atmospheric neutrino flux at high neutrino energies by studying its sensitivity to the cuts on several kinematical variables crucial for charm production in cosmic ray scattering in the atmosphere. This includes the maximal center-of-mass energy for proton-proton scattering, the longitudinal momentum fractions of partons in the projectile (cosmic ray) and target (nucleus of the atmosphere), the Feynman $x_F$ variable and the transverse momentum of charm quark/antiquark. We find that the production of neutrinos with energies larger than $E_{\nu} >$ 10$^7$ GeV is particularly sensitive to the center-of-mass energies larger than the ones at the LHC and to the longitudinal momentum fractions in the projectile 10$^{-8}$ $< x <$ 10$^{-5}$. Clearly, these are regions where we do not control the parton, in particular gluon, densities. We also analyse the characteristic theoretical uncertainties in the charm production cross section coming from its QCD modelling. The precision data on the prompt atmospheric neutrino flux can efficiently constrain the mechanism of heavy quark production and underlying QCD dynamics in kinematical ranges beyond the reach of the current collider measurements.Comment: 11 pages, 9 figure

Functional Evaluation of The Reducible Lower Radioulnar Joint Disruption between below Elbow Slab and Percutaneus Ulnoradial Pinning Surgical Treatments in Adult Patients with Galeazzi Fracture

Background: Incidence of Galeazzi fracture is relatively rare, but it requires correct management to attain desirable outcome and to prevent functional disorder in the affected patients. Generally, radius shaft plating is considered the best method to produce desirable outcome. However, there are some options to choose for DRUJ dysfunction management. No previous evaluation has been conducted on the functional effect of distal radio-ulnar joint (DRUJ) disruption in patients with Galeazzi fracture at Prof. DR. R. Soeharso Orthopedi Hospital. This study aimed to evaluate the relative effects of below elbow slab and percutaneus ulnoradial pinning surgical treatments on the reducible lower radioulnar joint disruption in adult patients with Galeazzi fracture. Subjects and Method: This was a cohort study conducted at Prof. Dr. R. Soeharso Orthopedi Hospital, Surakarta, Central Java, from January to December 2012. A total of 39 adult patients with Galeazzi fracture consisting of 23 with percutaneus pinning and 16 with below elbow slab treatment were selected for this study. The dependent variable was reducible lower radio-ulnar joint disruption. The independent variable was type of surgical treatment (below elbow slab versus percutaneus ulnoradial pinning). After 34 week follow-up period, the outcomes of these surgical treatments, i.e. the functional evaluation of reducible lower radio-ulnar joint disruption, were measured by Mikic criteria. The outcome data between the two types of surgical treatment were compared and tested by chi-square test. Results: The score of functional evaluation of reducible lower radio-ulnar joint disruption in patients who underwent below elbow slab surgical treatment was comparable with counterpart who underwent percutaneus ulnoradial pinning surgical treatment, and it was statistically non significant. Conclusion: Below elbow slab surgical treatment and percutaneus ulnoradial pinning surgical treatment result in comparable good outcomes in adult patients with Galeazzi fracture. Keywords: below elbow slab, percutaneus ulnoradial pinning, surgical treatment, Galeazzi fracture

Using the Chu Construction for generalizing formal concept analysis

L. Antoni, I. P. Cabrera, S. Krajči, O. Krídlo, and M. Ojeda-Aciego. Using the Chu construction for generalizing formal concept analysis. In CLA 2015, pp. 147–158, Blaise Pascal University, LIMOS laboratory, Clermont-Ferrand, 2015El objetivo de este artículo es mostrar la conexión entre generalizaciones de Análisis de Conceptos Formales y la construcción de Chu sobre la categoría ChuCors de contextos formales y correspondencias de Chu. Todas las propiedades categóricas necesarias para la comprensión de los resultados de este trabajo como producto categórico, producto tensorial o propiedades de su bifuntor se presentan y demuestran. Finalmente, la generalización de Análisis de Conceptos Formales de segundo orden se representa por una categoría construida en términos de la Construcción de Chu