3,391 research outputs found
Design of a Torque Current Generator for Strapdown Gyroscopes
The design, analysis, and experimental evaluation of an optimum performance torque current generator for use with strapdown gyroscopes, is presented. Among the criteria used to evaluate the design were the following: (1) steady-state accuracy; (2) margins of stability against self-oscillation; (3) temperature variations; (4) aging; (5) static errors drift errors, and transient errors, (6) classical frequency and time domain characteristics; and (7) the equivalent noise at the input of the comparater operational amplifier. The DC feedback loop of the torque current generator was approximated as a second-order system. Stability calculations for gain margins are discussed. Circuit diagrams are shown and block diagrams showing the implementation of the torque current generator are discussed
Application of Earth Resources Technology Satellite data to urban development and regional planning: Test site - County of Los Angeles
There are no author-identified significant results in this report
Advertising paid and unpaid job roles in sport: an updated position statement from the UK Strength and Conditioning Association
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From Egypt to Lithuania:Marija Rudzinskaitė-Arcimavičienė’s Mummy and its Radiological Investigation
Polymorphisms of the macrophage migration inhibitory factor gene in a UK population with Type 1 diabetes mellitus
Improved Standpipe Entrance for Stable High-Flux Flow
Cold model tests were used to show the causes of instabilities in the operation of the standpipe entrance (“sore thumb”) in industrial scale fluid cokers. New geometries were tested which might provide higher flows and prevent operating problems such as flow reversals and flooding, while also minimizing the adverse effects of fouling. The tests were conducted using FCC particles in a geometrically and dynamically scaled half-column of approximately 1/9th scale which had previously been used to show the effects of baffles on fluid coker strippers. The addition of sloping surfaces to increase the surface area for ingress of particles was helpful to an extent, but excessive overhang resulted in bubbles being drawn in. A perforated top surface was found to be instrumental in the degassing of the solids, whereas porous side area was essential for solids entry. Aeration of the standpipe reduced stick-slip flow, but excessive aeration made degassing more difficult and therefore promoted flow reversal. Loss of area at the top, and to a lesser extent, at the sides was found to be detrimental to the performance of the standpipe entrance. Several new geometries were tested, leading to one that provided better flow stability, improved flow control, excellent pressure build-up in the standpipe, more tolerance to fouling, and enhanced circulation capacity
Late Miocene to early Pliocene biofacies of Wanganui and Taranaki Basins, New Zealand: Applications to paleoenvironmental and sequence stratigraphic analysis
The Matemateaonga Formation is late Miocene to early Pliocene (upper Tongaporutuan to lower Opoitian New Zealand Stages) in age. The formation comprises chiefly shellbeds, siliciclastic sandstone, and siltstone units and to a lesser extent non-marine and shallow marine conglomerate and rare paralic facies. The Matemateaonga Formation accumulated chiefly in shelf paleoenvironments during basement onlap and progradation of a late Miocene to early Pliocene continental margin wedge in the Wanganui and Taranaki Basins. The formation is strongly cyclothemic, being characterised by recurrent vertically stacked facies successions, bounded by sequence boundaries. These facies accumulated in a range of shoreface to mid-outer shelf paleoenvironments during conditions of successively oscillating sea level. This sequential repetition of facies and the biofacies they enclose are the result of sixth-order glacio-eustatic cyclicity. Macrofaunal associations have been identified from statistical analysis of macrofossil occurrences collected from multiple sequences. Each association is restricted to particular lithofacies and stratal positions and shows a consistent order and/or position within the sequences. This pattern of temporal paleoecologic change appears to be the result of lateral, facies-related shifting of broad biofacies belts, or habitat-tracking, in response to fluctuations of relative sea level, sediment flux, and other associated paleoenvironmental variables. The associations also show strong similarity in terms of their generic composition to biofacies identified in younger sedimentary strata and the modern marine benthic environment in New Zealand
Using Humic Fractions to Understand Natural Organic Matter Processes in Soil and Water: Selected Studies and Applications
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