Abstract The RHIC interaction rate at sPHENIX will reach around 3 MHz in pp collisions and requires the detector readout to reject events by a factor of over 200 to fit the DAQ bandwidth of 15 kHz. ...Some critical measurements, such as heavy flavor production in pp collisions, often require the analysis of particles produced at low momentum. This prohibits adopting the traditional approach, where data rates are reduced through triggering on rare high momentum probes. We explore a new approach based on real-time AI technology, adopt an FPGA-based implementation using a custom designed FELIX-712 board with the Xilinx Kintex Ultrascale FPGA, and deploy the system in the detector readout electronics loop for real-time trigger decision.
What Does It Take to Complete the Cape Epic? Reinpõld, Karmen; Bossi, Arthur H; Hopker, James G
Journal of strength and conditioning research,
2022-Dec-01, 2022-12-00, 20221201, Letnik:
36, Številka:
12
Journal Article
Recenzirano
Odprti dostop
Reinpõld, K, Bossi, AH, and Hopker, JG. What does it take to complete the cape epic? J Strength Cond Res 36(12): 3513-3520, 2022-This study aimed to describe the racing and training demands of the ...Cape Epic. Six male mountain bike riders (age: 39 ± 7 years, height: 181 ± 3 cm, and body mass: 78.7 ± 8.1 kg) trained for 4.5 months and took part in the Cape Epic. Training and racing data (prologue, stage 1, and 2) were analyzed, and riders were tested in the laboratory on 3 distinct occasions for maximal oxygen uptake (V̇O 2 max), maximal work rate (Ẇmax), and power output associated with the respiratory compensation point (RCP PO ). Statistical significance was set at p ≤ 0.05. With race durations of 1.5 ± 0.2, 6.5 ± 1.2, and 6.4 ± 1.4 hours for, respectively, prologue, stage 1, and 2, normalized power was higher in prologue (3.73 ± 0.72 W·kg -1 ) compared with stages 1 (3.06 ± 0.59 W·kg -1 , p < 0.001) and 2 (2.94 ± 0.69 W·kg -1 , p < 0.001). Riders spent more time in power zones 1 and 2 (as %RCP PO ) and less time in zones 4 and 5, during stage 2 compared with prologue (all zones p ≤ 0.028). Despite no changes in V̇O 2 max or Ẇmax, RCP PO increased from midtraining (3.89 ± 0.61 W·kg -1 ) to prerace testing (4.08 ± 0.64 W·kg -1 , p = 0.048). No differences were found between base and build training phases for time in power zones. In conclusion, the Cape Epic requires an ability to sustain high submaximal power outputs for several hours as well as an ability to repeat high-intensity efforts throughout the race. A well-balanced program, incorporating a pyramidal intensity distribution, may be used as a starting point for the design of optimal training approaches.
Maximal oxygen uptake (V˙O2max) is a key determinant of endurance performance. Therefore, devising high-intensity interval training (HIIT) that maximizes stress of the oxygen-transport and ...-utilization systems may be important to stimulate further adaptation in athletes. The authors compared physiological and perceptual responses elicited by work intervals matched for duration and mean power output but differing in power-output distribution.
Fourteen cyclists (V˙O2max 69.2 6.6 mL·kg-1·min-1) completed 3 laboratory visits for a performance assessment and 2 HIIT sessions using either varied-intensity or constant-intensity work intervals.
Cyclists spent more time at >90%V˙O2max during HIIT with varied-intensity work intervals (410 207 vs 286 162 s, P = .02), but there were no differences between sessions in heart-rate- or perceptual-based training-load metrics (all P ≥ .1). When considering individual work intervals, minute ventilation (V˙E) was higher in the varied-intensity mode (F = 8.42, P = .01), but not respiratory frequency, tidal volume, blood lactate concentration La, ratings of perceived exertion, or cadence (all F ≤ 3.50, ≥ .08). Absolute changes (Δ) between HIIT sessions were calculated per work interval, and Δ total oxygen uptake was moderately associated with ΔV˙E (r = .36, P = .002).
In comparison with an HIIT session with constant-intensity work intervals, well-trained cyclists sustain higher fractions of V˙O2max when work intervals involved power-output variations. This effect is partially mediated by an increased oxygen cost of hyperpnea and not associated with a higher La, perceived exertion, or training-load metrics.
There are several published equations to calculate energy expenditure (EE) from gas exchanges. We assessed whether using different EE equations would affect gross efficiency (GE) estimates and their ...reliability.
Eleven male and three female cyclists (age: 33 ± 10 years; height: 178 ± 11 cm; body mass: 76.0 ± 15.1 kg; maximal oxygen uptake: 51.4 ± 5.1 ml·kg
·min
; peak power output: 4.69 ± 0.45 W·kg
) completed five visits to the laboratory on separate occasions. In the first visit, participants completed a maximal ramp test to characterize their physiological profile. In visits two to five, participants performed four identical submaximal exercise trials to assess GE and its reliability. Each trial included three 7-min bouts at 60%, 70% and 80% of the gas exchange threshold. EE was calculated with four equations by Péronnet & Massicotte, Lusk, Brouwer and Garby & Astrup.
All four EE equations produced GE estimates that differed from each other (all P < 0.001). Reliability parameters were only affected when the typical error was expressed in absolute GE units, suggesting a negligible effect-related to the magnitude of GE produced by each EE equation. The mean coefficient of variation for GE across different exercise intensities and calculation methods was 4.2%.
Although changing the EE equation does not affect GE reliability, exercise scientists and coaches should be aware that different EE equations produce different GE estimates. Researchers are advised to share their raw data to allow for GE recalculation, enabling comparison between previous and future studies.
Contact-angle measurements were used to determine the surface energies of graphite/epoxy composites before and after grit-blasting with 80- and 220-grit garnet particles. Two different composite ...systems cured at 350°F were considered but they behaved similarly. Contact angles made by a series of liquids, including water, ethylene glycol, glycerol, formamide, and methylene iodide on as-tooled and grit-blasted composite panels were measured using a contact-angle goniometer. The contact angles were used to determine the dispersive and polar components of the surface energy
. However, instead of using the contact angles made by two liquids to determine the two components of the surface energy, we used the contact angles made by several liquids and a graphical technique to determine
and to improve the accuracy of the measurements. It was found that the surface energies of as-tooled composites were approximately 35 mJ/m
2
and were mostly dispersive; the polar components were small. After grit-blasting with 80- or 220-grit garnet, the dispersive component of the surface energy decreased somewhat whereas the polar component increased significantly; the total surface energy after grit-blasting with 80- or 220-grit garnet was approximately 50 mJ/m
2
. Etching composites in oxygen plasmas had a similar effect on the dispersive and polar components of the surface energy and on the total surface energy. Grit-blasting with 220-grit alumina resulted in higher dispersive components of surface energy and lower polar components than grit-blasting with 220-grit garnet even though the total surface energy was similar after grit-blasting with 220-grit garnet and alumina. Correcting the measured surface energies for the effects of roughness resulted in small decreases in the total surface energy of the grit-blasted composites. However, even after correcting for roughness, the surface energies of the grit-blasted composites were still significantly greater than those of the as-tooled composites, indicating that grit-blasting resulted in changes in surface chemistry as well as changes in surface morphology of the composites. These changes in surface chemistry certainly included the removal of mold release agents from the as-tooled composites but probably also involved the creation of free radicals and their reaction with atmospheric oxygen to introduce oxygen-containing functional groups on the surfaces of the composites.
To describe pacing strategy in a 24-h running race and its interaction with sex, age group, athletes' performance group, and race edition.
Data from 398 male and 103 female participants of 5 editions ...were obtained based on a minimum 19.2-h effective-running cutoff. Mean running speed from each hour was normalized to the 24-h mean speed for analyses.
Mean overall performance was 135.6 ± 33.0 km with a mean effective-running time of 22.4 ± 1.3 h. Overall data showed a reverse J-shaped pacing strategy, with a significant reduction in speed from the second-to-last to the last hour. Two-way mixed ANOVAs showed significant interactions between racing time and both athlete performance group (F = 7.01, P < .001, η
= .04) and race edition (F = 3.01, P < .001, η
= .02) but not between racing time and either sex (F = 1.57, P = .058, ηp 2 < .01) or age group (F = 1.25, P = .053, η
= .01). Pearson product-moment correlations showed an inverse moderate association between performance and normalized mean running speed in the first 2 h (r = -.58, P < .001) but not in the last 2 h (r = .03, P = .480).
While the general behavior represents a rough reverse J-shaped pattern, the fastest runners start at lower relative intensities and display a more even pacing strategy than slower runners. The "herd behavior" seems to interfere with pacing strategy across editions, but not sex or age group of runners.
To describe pacing strategy and competitive behavior in elite-level cyclo-cross races.
Data from 329 men and women competing in 5 editions (2012-2016) of Union Cycliste Internationale Cyclo-Cross ...World Championships were compiled. Individual mean racing speeds from each lap were normalized to the mean speeds of the whole race. Lap and overall rankings were also explored. Pacing strategy was compared between sexes and between top- and bottom-placed cyclists.
A significant main effect of laps was found in 8 out of 10 races (4 positive, 3 variable, 2 even, and 1 negative pacing strategies), and an interaction effect of ranking-based groups was found in 2 (2016, male and female races). Kendall tau-b correlations revealed an increasingly positive relationship between intermediate and overall rankings throughout the races. The number of overtakes during races decreased from start to finish, as suggested by significant Friedman tests. In the first lap, normalized cycling speeds were different in 3 out of 5 editions-men were faster in 1 and slower in 2 editions. In the last lap, however, normalized cycling speeds of men were lower than those of women in 4 editions.
Elite cyclo-cross competitors adopt slightly distinct pacing strategies in each race, but positive pacing strategies are highly probable in most events, with more changes in rankings during the first laps. Sporadically, top- and bottom-placed groups might adopt different pacing strategies during either men's or women's races. Men and women seem to distribute their efforts differently, but this effect is of small magnitude.
The aim of this study was to describe the pacing during a 6-h ultramarathon (race 1) and to investigate whether a slow-start affects performance, running kinematic changes, ratings of perceived ...exertion (RPE) and fatigue (ROF) (race 2). After a critical speed test, participants completed two 6-h ultramarathons. Race 1 (n = 16) was self-paced, whereas in race 2 (n = 10), athletes performed the initial 36 min at speeds 18% below the mean speed of the initial 36 min of race 1. In race 1, participants adopted an inverse sigmoid pacing. Contact times increased after 1 h, and flight times decreased after 30 min (all P ≤ .009); stride length reduced after 1 h 30 min (all P = .022), and stride frequency did not change. Despite the lower speeds during the first 10% of race 2, and higher speeds at 50% and 90%, performance remained unchanged (57.5 ± 10.2 vs. 56.3 ± 8.5 km; P = .298). However, RPE and ROF were lowered for most of race 2 duration (all P < .001). For the comparison of kinematic variables between races, data were normalised by absolute running speed at each time point from 1 h onwards. No differences were found for any of the kinematic variables. In conclusion, decreasing initial speed minimises RPE and ROF, but does not necessarily affect performance. In addition, running kinematic changes do not seem to be affected by pacing manipulation.
Eddy-current testing (ECT) is widely used in inspection of multilayer aircraft skin structures for the detection of cracks under fasteners (CUF). Detection of deep hidden CUF poses a major challenge ...in traditional ECT techniques largely because the weak eddy-current signal due to a subsurface crack is dominated by the strong signal from the aluminum or steel fastener. Giant magnetoresistive (GMR) sensors are finding increasing applications in directly measuring weak magnetic fields associated with induced eddy currents. The measured flux image at a fastener site is in general symmetric and an asymmetry is introduced by the presence of a subsurface crack, which is used for defect detection. This paper presents novel methods that employ the resident phase information, for improving detection probability of GMR signal analysis. Using computational model, the effectiveness of the proposed methods for enhancing detection of CUF is investigated. Results demonstrating the potential of these techniques for detection of second layer CUF are presented.
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