1,998 research outputs found
Modulation and coding used by a major satellite communications company
Hughes Communications Inc., is a major satellite communications company providing or planning to provide the full spectrum of services available on satellites. All of the current services use conventional modulation and coding techniques that were well known a decade or longer ago. However, the future mobile satellite service will use significantly more advanced techniques. JPL, under NASA sponsorship, has pioneered many of the techniques that will be used
Evaluation of advanced lift concepts and potential fuel conservation for short-haul aircraft
The effect of different field lengths, cruise requirements, noise level, and engine cycle characteristics on minimizing fuel consumption and minimizing operating cost at high fuel prices were evaluated for some advanced short-haul aircraft. The conceptual aircraft were designed for 148 passengers using the upper surface-internally blown jet flap, the augmentor wing, and the mechanical flap lift systems. Advanced conceptual STOL engines were evaluated as well as a near-term turbofan and turboprop engine. Emphasis was given to designs meeting noise levels equivalent to 95-100 EPNdB at 152 m (500 ft) sideline
Effect of high oxygen pressure annealing on superconducting Nd1.85Ce0.15CuO4 thin films by pulsed laser deposition from Cu-enriched targets
We show that the quality of Nd1.85Ce0.15CuO4 films grown by pulsed laser
deposition can be enhanced by using a non-stoichiometric target with extra
copper added to suppress the formation of a parasitic (Nd, Ce)2O3 phase. The
properties of these films are less dependent on the exact annealing procedure
after deposition as compared to films grown from a stoichiometric target. Film
growth can be followed by a 1 bar oxygen annealing, after an initial vacuum
annealing, while retaining the superconducting properties and quality. This
enables the integration of electron-doped cuprates with their hole-doped
counterparts on a single chip, to create, for example, superconducting
pn-junctions.Comment: This is an author-created, un-copyedited version of an article
accepted for publication in Superconductor Science and Technology. The
publisher is not responsible for any errors or omissions in this version of
the manuscript or any version derived from it. The Version of Record is
available online at http://dx.doi.org/10.1088/0953-2048/27/4/04401
Strain accommodation through facet matching in LaSrCuO/NdCeCuO ramp-edge junctions
Scanning nano-focused X-ray diffraction (nXRD) and high-angle annular
dark-field scanning transmission electron microscopy (HAADF-STEM) are used to
investigate the crystal structure of ramp-edge junctions between
superconducting electron-doped NdCeCuO
and superconducting hole-doped LaSrCuO
thin films, the latter being the top layer. On the ramp, a new growth mode of
LaSrCuO with a 3.3 degree tilt of the
c-axis is found. We explain the tilt by developing a strain accommodation model
that relies on facet matching, dictated by the ramp angle, indicating that a
coherent domain boundary is formed at the interface. The possible implications
of this growth mode for the creation of artificial domains in morphotropic
materials are discussed.Comment: 5 pages, 4 figures & 3 pages supplemental information with 2 figures.
Copyright (2015) American Institute of Physics. This article may be
downloaded for personal use only. Any other use requires prior permission of
the author and the American Institute of Physics. The following article
appeared in APL Mat. 3, 086101 (2015) and may be found at
http://dx.doi.org/10.1063/1.492779
Acute Administration of Bioavailable Curcumin Alongside Ferrous Sulphate Supplements Does Not Impair Iron Absorption in Healthy Adults in a Randomised Trial.
Ferrous sulphate (FS) is a cost effective, readily available iron supplement for iron deficiency (ID). The pro-oxidant effect of oral ferrous iron is known to induce inflammation, causing gastric side-effects and resulting in poor compliance. Curcumin is a potent antioxidant and has also been shown to exhibit iron chelation in-vitro, although it is not established whether these effects are retained in-vivo. The aim of this study was therefore to assess the influence of a formulated bioavailable form of curcumin (HydroCurc ; 500 mg) on acute iron absorption and status in a double blind, placebo-controlled randomized trial recruiting 155 healthy participants (79 males; 26.42 years ± 0.55 and 76 females; 25.82 years ± 0.54). Participants were randomly allocated to five different treatment groups: iron and curcumin placebo (FS0_Plac), low dose (18 mg) iron and curcumin placebo (FS18_Plac), low dose iron and curcumin (FS18_Curc), high dose (65 mg) iron and curcumin placebo (FS65_Plac), and high dose iron and curcumin (FS65_Curc). Participants were provided with the supplements according to their relevant treatment groups at baseline (0 min), and blood collection was carried out at 0 min and at 180 min following supplementation. In the treatment groups, significant difference was observed in mean serum iron between baseline (0 min) and at end-point (180 min) (F (1, 144) = 331.9, < 0.0001) with statistically significant intra-group increases after 180 min ( < 0.0001) in the FS18_Plac (8.79 µmol/L), FS18_Curc (11.41 µmol/L), FS65_Plac (19.09 µmol/L), and FS65_Curc (16.39 µmol/L) groups. A significant difference was also observed between the two time points in serum TIBC levels and in whole blood haemoglobin (HGB) in the treatment groups, with a significant increase (1.55%/2.04 g/L) in HGB levels from baseline to end-point observed in the FS65_Curc group ( < 0.05). All groups receiving iron demonstrated an increase in transferrin saturation (TS%) in a dose-related manner, demonstrating that increases in serum iron are translated into increases in physiological iron transportation. This study demonstrates, for the first time, that regardless of ferrous dose, formulated curcumin in the form of HydroCurc™ does not negatively influence acute iron absorption in healthy humans
Evaluation of active control technology for short haul aircraft
An evaluation of the economics of short-haul aircraft designed with active controls technology and low wing-loading to achieve short field performance with good ride quality is presented. Results indicate that for such a system incorporating gust load alleviation and augmented stability the direct operating cost is better than for aircraft without active controls
Manipulating electronic states at oxide interfaces using focused micro X-rays from standard lab-sources
Recently, x-ray illumination, using synchrotron radiation, has been used to
manipulate defects, stimulate self-organization and to probe their structure.
Here we explore a method of defect-engineering low-dimensional systems using
focused laboratory-scale X-ray sources. We demonstrate an irreversible change
in the conducting properties of the 2-dimensional electron gas at the interface
between the complex oxide materials LaAlO3 and SrTiO3 by X-ray irradiation. The
electrical resistance is monitored during exposure as the irradiated regions
are driven into a high resistance state. Our results suggest attention shall be
paid on electronic structure modification in X-ray spectroscopic studies and
highlight large-area defect manipulation and direct device patterning as
possible new fields of application for focused laboratory X-ray sources.Comment: 12 pages, 4 figure
Alternate wet/dry irrigation in rice cultivation: a practical way to save water and control malaria and Japanese encephalitis?
Water management / Water scarcity / Water use efficiency / Water conservation / Irrigated farming / Waterborne diseases / Rice / Malaria / Disease vectors / Productivity / Flood irrigation / Environmental control / Climate / China / East Africa / India / Indonesia / Japan / Philippines / Portugal / USA
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