5,774 research outputs found
The total mass of super-Brownian motion upon exiting balls and Sheu's compact support condition
We study the total mass of a d-dimensional super-Brownian motion as it first
exits an increasing sequence of balls. The process of the total mass is a
time-inhomogeneous continuous-state branching process, where the increasing
radii of the balls are taken as the time parameter. We are able to characterise
its time-dependent branching mechanism and show that it converges, as time goes
to infinity, towards the branching mechanism of the total mass of a
one-dimensional super-Brownian motion as it first crosses above an increasing
sequence of levels. Our results allow us to identify the compact support
criterion given in Sheu (1994) as a classical Grey condition (1974) for the
aforementioned limiting branching mechanism.Comment: 28 pages, 2 figure
Magnetic Properties of Pr0.7Ca0.3MnO3/SrRuO3 Superlattices
High-quality Pr0.7Ca0.3MnO3/SrRuO3 superlattices were fabricated by pulsed
laser deposition and were investigated by high-resolution transmission electron
microscopy and SQUID magnetometry. Superlattices with orthorhombic and
tetragonal SrRuO3 layers were investigated. The superlattices grew coherently;
in the growth direction Pr0.7Ca0.3MnO3 layers were terminated by MnO2- and
SrRuO3 layers by RuO2-planes. All superlattices showed antiferromagnetic
interlayer coupling in low magnetic fields. The coupling strength was
significantly higher for orthorhombic than for tetragonal symmetry of the
SrRuO3 layers. The strong interlayer exchange coupling in the superlattice with
orthorhombic SrRuO3 layers led to a magnetization reversal mechanism with a
partially inverted hysteresis loop.Comment: 12 pages, 4 figure
Scattering of non-uniform incident fields by long cylinders
Copyright University of BremenWe investigate experimentally far-field scattering from cylinders with illumination non-uniform along the axis of the cylinder. Scattered intensity as a function of angle in two orthogonal directions is examined. Variation along the scattering angle is found to be little affected by the illumination profile. However, variation in the transverse direction follows closely the Fourier transform of the illumination pattern and reproduces the angular distribution of the incident wave. These finding apply to circular as well as hexagonal cross-section cylinders
A light scattering instrument for investigating cloud ice microcrystal morphology
We describe an optical scattering instrument designed to assess the shapes and sizes of microscopic atmospheric cloud particles, especially the smallest ice crystals that can profoundly affect cloud processes and radiative properties yet cannot be seen clearly using in situ cloud particle imaging probes. The new instrument captures high-resolution spatial light scattering patterns from individual particles down to ~1 ÎŒm in size passing through a laser beam. Its significance lies in the ability of these patterns to provide morphological data for particle sizes well below the optical resolution limits of current probes
A Business Transformation Model for Legacy Carriers as a Response to the Rise of Low-Cost Carriers
The aviation travel industry offers today a commodity product that attracts all types of customers. However, many clients are price-sensitive and often look for the cheapest product offering. As legacy airlinesâ core strengths do not align well with the new customer preferences, this research work investigates the background of the rise of the low-cost carriers and consequently proposes a wholistic transformational model for legacy airlines. This paper presents a business transformation model with five strategic areas. The first two areas, which are Modernization and Environmental Sustainability, advise legacy carriers to focus on digitizing large parts of their business and establish operations within a sustainable business model. The next two areas are the adaptation of products offered with stronger people-centric marketing and communication strategies. The final area is the optimization of portfolio management, where legacy carriers are urged to rethink their investment strategy and possibly divest from low-cost carrier subsidiaries
The INTEGRAL-OMC Scientific Archive
The Optical Monitoring Camera (OMC) on-board the INTEGRAL satellite has, as
one of its scientific goals, the observation of a large number of variable
sources previously selected. After almost 6 years of operations, OMC has
monitored more than 100 000 sources of scientific interest. In this
contribution we present the OMC Scientific Archive
(http://sdc.laeff.inta.es/omc/) which has been developed to provide the
astronomical community with a quick access to the light curves generated by
this instrument.We describe the main characteristics of this archive, as well
as important aspects for the users: object types, temporal sampling of light
curves and photometric accuracy.Comment: 4 pages, 5 figures. "Highlights of Spanish Astrophysics V"
Proceedings of the VIII Scientific Meeting of the Spanish Astronomical
Society (SEA) held in Santander, July 7-11, 200
Cross-Sectional Analysis of Sediment and Organic Matter from Transects Across the Lower Unchannelized Missouri River
The United States Army Corps of Engineers, U.S. Geological Survey, and Nebraska Game and Parks Commission cooperated in 1989 to obtain physical data from cross-section transects along the unchannelized Missouri River in northeastern Nebraska. Bed-sediment samples were collected from locations along these transects and taken to the laboratory. Mean particle-size and standard deviation were determined by weighing material retained on seven U.S. Standard sieves after being on a sieve shaker for six minutes. Organic matter content of each sample was obtained by ashing an aliquot in a muffle furnace to remove the organic portion. A new system for coding sediment mixtures was developed, and coded sediment and organic matter content were compared with depth and velocity in a regression analysis. The most common mean particle-size was determined to be medium sand; however, some samples were as coarse as fine gravel. Organic-matter content was less then 3% for the most part; however, it was measured as high as 20%. Sediment and organic matter were related to depth and velocity; however, r-square values were low, suggesting that other factors contribute to the observed variability in the sediment mixtures and organic matter content
Cross-Sectional Analysis of Sediment and Organic Matter from Transects Across the Lower Unchannelized Missouri River
The United States Army Corps of Engineers, U.S. Geological Survey, and Nebraska Game and Parks Commission cooperated in 1989 to obtain physical data from cross-section transects along the unchannelized Missouri River in northeastern Nebraska. Bed-sediment samples were collected from locations along these transects and taken to the laboratory. Mean particle-size and standard deviation were determined by weighing material retained on seven U.S. Standard sieves after being on a sieve shaker for six minutes. Organic matter content of each sample was obtained by ashing an aliquot in a muffle furnace to remove the organic portion. A new system for coding sediment mixtures was developed, and coded sediment and organic matter content were compared with depth and velocity in a regression analysis. The most common mean particle-size was determined to be medium sand; however, some samples were as coarse as fine gravel. Organic-matter content was less then 3% for the most part; however, it was measured as high as 20%. Sediment and organic matter were related to depth and velocity; however, r-square values were low, suggesting that other factors contribute to the observed variability in the sediment mixtures and organic matter content
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