10,032 research outputs found
Decoders for MST radars
Decoding techniques and equipment used by MST radars are described and some recommendations for new systems are presented. Decoding can be done either by software in special-purpose (array processors, etc.) or general-purpose computers or in specially designed digital decoders. Both software and hardware decoders are discussed and the special case of decoding for bistatic radars is examined
Spectral moment estimation in MST radars
Signal processing techniques used in Mesosphere-Stratosphere-Troposphere (MST) radars are reviewed. Techniques which produce good estimates of the total power, frequency shift, and spectral width of the radar power spectra are considered. Non-linear curve fitting, autocovariance, autocorrelation, covariance, and maximum likelihood estimators are discussed
The Arecibo Observatory as an MST radar
The radars and other systems at the Arecibo Observatory were designed and built, originally, for incoherent-scatter and radio-astronomy research. More recently, important additions have been made for planetary radar and artificial RF heating of the ionosphere. Although designed and built for a different application, these systems have shown to be very powerful tools for tropospheric, stratospheric and mesospheric research. The Observatory at present has two main radars: one at 430 and the other at 2380 MHz. In addition, 50-MHz MST radar work has been done using portable transmitters brought to the Observatory for this purpose. This capability will become permanent with the recent acquisition of a transmitter at this frequency. Furthermore, control and data processing systems have been developed to use the powerful HF transmitter and antennas of the HF-heating facility as an HF bistatic radar. A brief description of the four radars available at the Observatory is presented
Environmental advertising in China and the USA: the desire to go green
Book Review
Environmental advertising in China and the USA: the desire to go green, by Xinghua Li, London and New York, NY, Routledge, 2016, 158 pp., £90.00 (hardback), ISBN 978-415-74413-
The Role of Repression in the Incidence of Ironic Errors
The role of repression in the incidence of ironic errors was investigated on a golf task. Coping styles of novice golfers were determined using measures of cognitive anxiety and physiological arousal. Following baseline putts, participants (n = 58) performed a competition putt with the opportunity to win UK£50 (approx. US$100). Before completing the competition putt participants were instructed to “land the ball on the target, but be particularly careful not to over-shoot the target.” The distance the ball traveled past the hole formed the measure of ironic effects. Probing of the coping style × condition interaction, F(2, 41) = 6.53, p < .005, revealed that only the repressors incurred a significant increase in ironic error for the competition putt. This suggests that the act of repressing anxiety has a detrimental performance effect
Visibility studies in archaeology: a review and case study
This paper describes the history and current state of archaeological visibility studies. The first part is a survey of both GIS (geographic information systems) and non-GIS studies of visibility by archaeologists, which demonstrates how advances in GIS visibility studies have tended to recapitulate, albeit over a compressed timescale, theoretically driven developments in non-GIS studies. The second part presents an example of the kind of methodological development required for the use of GIS to contribute to the agenda set by certain strands of a more humanistic archaeology. An algorithm developed to retrieve various summaries of the inclination at which points on the horizon are visible from a specified viewpoint was applied to nineteen recumbent stone circles in the Grampian region of Scotland. The results suggest that these summaries provide a useful tool for 'unpacking' what archaeologists mean when they claim that the topographic setting of certain stone circles creates an 'impression of circularity'
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