4,409 research outputs found
Bernard Yarnton Mills 1920-2011
Bernie Mills is remembered globally as an influential pioneer in the evolving
field of radio astronomy. His contributions with the 'Mills Cross' at the CSIRO
Division of Radiophysics and later at the University of Sydney's School of
Physics and the development of the Molonglo Observatory Synthesis Telescope
(MOST) were widely recognised as astronomy evolved in the years 1948-1985 and
radio astronomy changed the viewpoint of the astronomer as a host of new
objects were discovered
Considerações sobre épocas de semeadura para a cultura da cevada.
bitstream/item/119393/1/FOL-06036.pd
Tune Determination of Strongly Coupled Betatron Oscillations in a Fast-Ramping Synchrotron
Tune identification - i.e. attribution of the spectral peak to a particular
normal mode of oscillations - can present a significant difficulty in the
presence of strong transverse coupling when the normal mode with a lower
damping rate dominates spectra of Turn-by-Turn oscillations in both planes. The
introduced earlier phased sum algorithm helped to recover the weaker normal
mode signal from the noise, but by itself proved to be insufficient for
automatic peak identification in the case of close phase advance distribution
in both planes. To resolve this difficulty we modified the algorithm by taking
and analyzing Turn-by-Turn data for two different ramps with the beam
oscillation excited in each plane in turn. Comparison of the relative
amplitudes of Fourier components allows for automatic correct tune
identification. The proposed algorithm was implemented in the Fermilab Booster
B38 console application and successfully used in tune, coupling and
chromaticity measurements.Comment: 3 pp. 3rd International Particle Accelerator Conference (IPAC 2012)
20-25 May 2012, New Orleans, Louisian
On Manility and Serality
The notion that different people consistently function best at different and specific times of day is subjected to further analysis and discussion of methodological difficulties. When factor analytic procedures are applied to behavior inventories which supposedly capture stable diurnal characteristics, more than one dimension of serality-manility emerges. Factor scores thus derived were correlated with the computed acrophases of several circadian functions. Certain results suggest sex differences in the underlying structure, besides the magnitude, of these relationships. Also, hormonal contraception may alter behavioral serality-manility
Two prehistoric archeological sites in Egyptian Nubia
The Yale University Prehistoric Expedition to Nubia was part of UNESCO\u27S international program to salvage the monuments of Nubia, with the direct aid of the Department of Antiquities of the United Arab Republic…
Interplanetary Magnetic Field Sector Polarity and Neuropsychiatric Adaption: a Reanalysis
Recent Russian studies reported associations between adaptation syndromes and (solar activity-related) interplanetary magnetic field (IMF) sector polarity. Certain ambiguities in the original work suggested some reanalyses, based on the graphs and data made available. Syndrome status exhibited a biphasic (semi annual) trend. It also correlated with specific geomagnetic changes during magnetic storms and possibly after sudden impulses. Moreover, lag effects and higher order interactions were noted among all parameters investigated. The restudy tends to support some of the original findings but also suggests new conclusions regarding potential relationships between geophysical/solar and psychophysiological processes
Thermal stress cycling of GaAs solar cells
A thermal cycling experiment was performed on GaAs solar cells to establish the electrical and structural integrity of these cells under the temperature conditions of a simulated low-Earth orbit of 3-year duration. Thirty single junction GaAs cells were obtained and tests were performed to establish the beginning-of-life characteristics of these cells. The tests consisted of cell I-V power output curves, from which were obtained short-circuit current, open circuit voltage, fill factor, and cell efficiency, and optical micrographs, spectral response, and ion microprobe mass analysis (IMMA) depth profiles on both the front surfaces and the front metallic contacts of the cells. Following 5,000 thermal cycles, the performance of the cells was reexamined in addition to any factors which might contribute to performance degradation. It is established that, after 5,000 thermal cycles, the cells retain their power output with no loss of structural integrity or change in physical appearance
A mobile system for active otpical pollution monitoring
The remote monitoring of atmospheric pollutants can now be performed in several ways. Laser radar techniques have proven their ability to reveal the spatial distribution of different species or particles. Classical optical techniques can also be used, but yield the average concentration over a given path and hence no range resolution. One such technique is Differential Optical Absorption Spectroscopy, DOAS. Such schemes can be used to monitor paths that a preliminary lidar investigation has shown to be of interest. Having previously had access to a mobile lidar system, a new system has been completed. The construction builds on experience from using the other system and it is meant to be more of a mobile optical laboratory than just a lidar system. A complete system description is given along with some preliminary usage. Future uses are contemplated
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