scholarly journals Aspects of operation of the Fermilab Booster RF System at very high intensity

1996 ◽  
Author(s):  
J.E. Griffin
Keyword(s):  
1995 ◽  
Vol 39 ◽  
pp. 109-117
Author(s):  
Burkhard Beckhoff ◽  
Birgit Kanngießer

X-ray focusing based on Bragg reflection at curved crystals allows collection of a large solid angle of incident radiation, monochromatization of this radiation, and condensation of the beam reflected at the crystal into a small spatial cross-section in a pre-selected focal plane. Thus, for the Bragg reflected radiation, one can achieve higher intensities than for the radiation passing directly to the same small area in the focal plane. In that case one can profit considerably from X-ray focusing in an EDXRF arrangement. The 00 2 reflection at Highly Oriented Pyrolytic Graphite (HOPG) crystals offers a very high intensity of the Bragg reflected beam for a wide range of photon energies. Furthermore, curvature radii smaller than 10 mm can be achieved for HOPG crystals ensuring efficient X-ray focusing in EDXRF applications. For the trace analysis of very small amounts of specimen material deposited on small areas of thin-filter backings, HOPG based X-ray focusing may be used to achieve a very high intensity of monochromatic excitation radiation.


2007 ◽  
Vol 14 (7) ◽  
pp. 072701 ◽  
Author(s):  
H. Hora ◽  
J. Badziak ◽  
M. N. Read ◽  
Yu-Tong Li ◽  
Tian-Jiao Liang ◽  
...  

2005 ◽  
Vol 100 (3) ◽  
pp. 767-773 ◽  
Author(s):  
Randall F. Gearhart ◽  
M. Daniel Becque ◽  
Chad M. Palm ◽  
Matthew D. Hutchins

This study compared undifferentiated ratings of perceived exertion (RPE) during short duration, very high intensity cycle exercise using high and low resistance. 30 recreationally trained males (24.2 ± 2.4 yr.) were memory-anchored to the Borg 15-category scale. The high and low resistance exercises were defined by 30-sec. maximum tests assigned in counterbalanced order, with resistances set before testing during an orientation session. High resistance was 10% of body mass. Low resistance resulted in the same total work as the high resistance over the 30-sec. sessions (± 5%) but increased pedal rate. RPE was taken at 8, 13, 18, 23, and 28 sec. during the high and the low resistance exercises. Measurements were compared using a 2-way repeated-measures analysis of variance. RPE was significantly greater ( p = .005) for the high than the low resistance exercise at each interval. RPE increased when the subjects were required to pedal against a greater resistance and produce the highest forces. These RPE data are consistent with data from both aerobic cycle and resistance exercise. The data suggest that instantaneous force production, not summed work, is a primary determinant of RPE. All of these observations support Cafarelli's theoretical model of effort sense. In conclusion, as an individual generates more force during high resistance exercise than in light resistance exercise, a potential explanation of our results is that the increased motor outflow and corollary sensory signal lead to a greater sense of effort.


The curve relating the smallest perceptible intensity of a blue test stimulus with the intensity of an orange conditioning field against which it is viewed shows a characteristic division into low- and high-intensity components, indicating the operation of two mechanisms of cone vision at the fovea. The justification for calling these ‘blue’ and ‘green’ mechanisms is taken from an earlier investigation (Stiles 1939). While most subjects show this division clearly, for some the low-intensity component is masked by the intrusion of rod vision. The correctness of this view is established by measurements made while the eye is recovering from an intense light adaptation. The individual variations of the sensitivities of the ‘green’ and ‘blue’ mechanisms in twenty subjects are assessed. Further evidence is obtained of an anomalously low threshold for the ‘blue’ mechanisms at very high conditioning fields of orange light.


2014 ◽  
Vol 35 ◽  
pp. 1460390
Author(s):  
SIMEONE DUSSONI

The MEG experiment started taking data in 2009 looking for the Standard Model suppressed decay μ → e + γ, which, if observed, can reveal Beyond Standard Model physics. It makes use of state-of-the art detectors optimized for operating in conditions of very high intensity, rejecting as much background as possible. The data taking ended August 2013 and an upgrade R&D is started to push the experimental sensitivity. The present upper limit on the decay Branching Ratio (BR) is presented, obtained with the subset of data from 2009 to 2011 run, together with a description of the key features of the upgraded detector.


2015 ◽  
Vol 47 (1) ◽  
pp. 179-188 ◽  
Author(s):  
Javier Mallo ◽  
Esteban Mena ◽  
Fabio Nevado ◽  
Víctor Paredes

AbstractThe aim of this study was to examine the physical demands imposed on professional soccer players during 11-a-side friendly matches in relation to their playing position, using global positioning system (GPS) technology. One hundred and eleven match performances of a Spanish “La Liga” team during the 2010-11 and 2011-12 pre-seasons were selected for analysis. The activities of the players were monitored using GPS technology with a sampling frequency of 1 Hz. Total distance covered, distance in different speed categories, accelerations, and heart rate responses were analyzed in relation to five different playing positions: central defenders (n=23), full-backs (n=20), central midfielders (n=22), wide midfielders (n=26), and forwards (n=20). Distance covered during a match averaged 10.8 km, with wide and central midfielders covering the greatest total distance. Specifically, wide midfielders covered the greatest distances by very high-intensity running (>19.8 km·h-1) and central midfielders by jogging and running (7.2-19.7 km·h-1). On the other hand, central defenders covered the least total distance and at high intensity, although carried out more (p<0.05-0.01) accelerations than forwards, wide midfielders, and fullbacks. The work rate profile of the players obtained with the GPS was very similar to that obtained with semi-automatic image technologies. However, when comparing results from this study with data available in the literature, important differences were detected in the amount of distance covered by sprinting, which suggests that caution should be taken when comparing data obtained with the GPS with other motion analysis systems, especially regarding high-intensity activities.


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