537 research outputs found
Letter, David Wingate to Jim Rodgers, Break in Project, July 10, 1979
No full textA letter from David Wingate, of the Department of Agriculture and Fisheries in Bermuda, to Jim Rodgers regarding his disappointment at a project being delayed.https://digitalcommons.usf.edu/audubon_coastal_islands_records/1128/thumbnail.jp
Anticipatory pacing strategies during supramaximal exercise lasting longer than 30 s
No full textPurpose: This study assessed whether pacing strategies are adopted during supramaximal exercise bouts lasting longer than 30 s. Methods: Eight healthy males performed six Wingate anaerobic tests (WAnT). Subjects were informed that they were performing four 30-s WAnT, a 33-s, and a 36-s WAnT. However, they actually completed two trials of 30, 33, and 36 s each. Temporal feedback in the deception trials was manipulated so that subjects were unaware of the time discrepancy. Power output was determined from the angular displacement of the flywheel. The peak power (PPI), mean power (MPI), and fatigue (FI) indices were calculated for each trial. Results: Power output was similar for all trials up to 30 s. However, at 36 s, the power output was significantly lower in the 36-s deception trial compared with the 36-s informed trial (392 ± 32 W vs 470 ± 88 W) (P < 0.001). The MPI was significantly lower in the 36-s trials (714 ± 76 W and 713 ± 78 W) compared with the 30-s trials (745 ± 65 W and 764 ± 82 W) although they were not different at 30 s (764 ± 83 W and 755 ± 79 W). The significant reduction in FI was greatest in the 36-s deception trial. Conclusions: The significant reduction in power output in the last 6 s of the 36-s deception trial, but not in the 36-s informed trial, indicates the presence of a preprogrammed 30-s end point based on the anticipated exercise duration from previous experience. The similarity in pacing strategy suggests that the pacing strategy is centrally regulated
Laramide deformation of the wingate sandstone, Colorado National Monument : a study of cataclastic flow
No full textTypescript (photocopy).During Laramide tectonism, the aeolian Wingate Sandstone was forced folded along the northeast of the Uncompahgre Plateau above faults within the underlying crystalline basement. The internal deformation of the Wingate occurred by the relative translation and rotation of this sandstone across mesoscopically discrete zones of intense deformation: a form of cataclastic flow. The basic form for these zones of localized deformation is the deformation band. Little of no internal deformation of the sandstone occurred between the deformation bands, either mesoscopically or microscopically. The deformation band initiates as a single band: a discrete, usually planar zone (~0.3 mm wide) within which sand grains are progressively comminuted and compacted with increasing offset along the band. The quartz grains within this zone appear to have been comminuted by a process of grain fracture assisted by crystal lattice creep mechanisms. With offset of more than ~0.5 mm additional band segments begin to form along the single band, creating an anastomosing band. In outcrop appearance, the deformation bands are lighter colored and more resistant than the undeformed sandstone. Cohesion of the rock is maintained across these features. Deformation bands usually form as conjugate shearing features, which intersect at an angle of 20�� to 40��. The bulk strain resulting from offset along the deformation bands increases linearly with band density. The distribution and density of deformation bands within the Wingate is a function of the relative and absolute amounts of rotation and translation of the basement surface that occurred across the fault zones within the underlying basement materials. The Wingate has an inherent strength anisotropy following cross-beds and cross-bed-set boundaries. Deformation bands parallel these features in the early phases of deformation. However, the deformation bands appear to displacement-harden. Consequently, the initial strength anisotropy of the Wingate is removed by progressive deformation
Smartlocks: Lock Acquisition Scheduling for Self-Aware Synchronization
No full textAs multicore processors become increasingly prevalent, system complexity is skyrocketing. The advent of the asymmetric multicore compounds this - it is no longer practical for an average programmer to balance the system constraints associated with today's multicores and worry about new problems like asymmetric partitioning and thread interference. Adaptive, or self-aware, computing has been proposed as one method to help application and system programmers confront this complexity. These systems take some of the burden off of programmers by monitoring themselves and optimizing or adapting to meet their goals.
This paper introduces a self-aware synchronization library for multicores and asymmetric multicores called Smartlocks. Smartlocks is a spin-lock library that adapts its internal implementation during execution using heuristics and machine learning to optimize toward a user-defined goal, which may relate to performance or problem-specific criteria. Smartlocks builds upon adaptation techniques from prior work like reactive locks [1], but introduces a novel form of adaptation that we term lock acquisition scheduling designed specifically to address asymmetries in multicores. Lock acquisition scheduling is optimizing which waiter will get the lock next for the best long-term effect when multiple threads (or processes) are spinning for a lock.
This work demonstrates that lock scheduling is important for addressing asymmetries in multicores. We study scenarios where core speeds vary both dynamically and intrinsically under thermal throttling and manufacturing variability, respectively, and we show that Smartlocks significantly outperforms conventional spin-locks and reactive locks. Based on our findings, we provide guidelines for application scenarios where Smartlocks works best versus less optimally
Smart data structures: An online learning approach to multicore data structures
No full textAs multicores become prevalent, the complexity of programming is skyrocketing. One major difficulty is efficiently orchestrating collaboration among threads through shared data structures. Unfortunately, choosing and hand-tuning data structure algorithms to get good performance across a variety of machines and inputs is a herculean task to add to the fundamental difficulty of getting a parallel program correct. To help mitigate these complexities, this work develops a new class of parallel data structures called Smart Data Structures that leverage online machine learning to adapt automatically. We prototype and evaluate an open source library of Smart Data Structures for common parallel programming needs and demonstrate significant improvements over the best existing algorithms under a variety of conditions. Our results indicate that learning is a promising technique for balancing and adapting to complex, time-varying tradeoffs and achieving the best performance available
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One way to live : Orde Wingate and the adoption of ‘special forces’ tactics and strategies (1903-1944)
No full textWinston Churchill declared Major-General Orde Wingate ‘a man of genius’ for developing what he considered low-cost, high-risk, and high-leverage operations in three theaters of the Second World War. One Way to Live: Orde Wingate and the adoption of 'special forces' tactics and strategies (1903-1944) tries to answer two questions: Why did Wingate and his superiors adopt 'special forces' strategies and tactics, and why did individuals choose to join his 'special forces' units? I use biography and comparative biography to help answer these two questions. I provide a narrative of Wingate's life, but I also construct biographical sketches of some of his peers, rivals, superiors, and followers during his campaigns in Sudan, Mandatory Palestine, Abyssinia, and Burma. I ultimately find that while Wingate's unusual upbringing contributed to his propensity for creating new military units, it was ultimately his aggressive competition with other British officers for scarce honor and prestige that spurred him to create the units he branded 'special forces.' His leaders, on the other hand, adopted Wingate's special forces strategies out of desperation, and only when they lacked the resources to win 'traditional' campaigns. Wingate's followers did not always volunteer to join his units (compulsion occurred in several instances), but many officers joined his ranks with the intention of obtaining a role in violent combat; like Wingate, they sought the prestige and role-fulfillment that some soldiers seek through war. Despite the inherent risks of special forces tactics, many soldiers paradoxically thought their odds of survival were higher with Wingate than in traditional military formations. In many instances, the competition between soldiers required more personal investment than any action against the ‘enemy.’
The extensive use of comparative biography encourages the examination of previously unused sources, including unpublished memoirs and oral histories. My writing, at times, examines stories that do not answer the central questions of the dissertation, but provide a rich understanding of the behavior of British soldiers in Palestine, Abyssinia, and elsewhere. As a social scientist, I attempt to understand the subject as a salient example of organized violence, and not just as a series of unique historical incidents.Governmen
Selected Contribution to the Deformation of Wingate Sandstone at the Sand Grain Scale
No full textProgram year: 1977-1978Digitized from print original stored in HDRThe study of sandstone deformation on grain-to-grain and grain scales is not unknown in the geological sciences. Using a ratio of solid space to void space (S/V) measured on the grain-to-grain scale in the Triassic Wingate sandstone it can be shown that the value of this ratio increases in compacted zones of similar lithologic character as compared with uncompacted zones. The value of S/V also increases in the vicinity of macroscopic shear fractures as compared with values in outlying areas. Three models are presented to explain the phenomena observed in this stud
Taekwondo Anaerobic Intermittent Kick Test: Discriminant Validity and an Update with the Gold-Standard Wingate Test
No full textInternational audienceThe aim of this study was to update the validity of the Taekwondo Anaerobic Intermittent Kick Test compared with the 30-s Wingate anaerobic test as the "Gold-Standard", squat jump and countermovement jump tests. The second objective was to examine whether this new specific test would be able to effectively discriminate between elite taekwondo athletes of different competitive levels. Twenty taekwondo athletes (15 males and 5 females) participated in the validation component, whereas 18 (14 males and 4 females) and 16 (13 males and 3 females) athletes participated in the reliability analysis of the Wingate anaerobic test and jumping tests, respectively. They performed these tests on two separate occasions (i.e., test-retest), in addition to the Taekwondo Anaerobic Intermittent Kick Test. To establish test's discriminatory capability (i.e., construct validity), two subgroups were identified based on their international and national taekwondo performance 10 elite (8 males and 2 females) and 9 sub-elite (7 males and 2 females) athletes. Wingate anaerobic test and jumping tests performances showed excellent reliability (ICC > 0.90, SEM < 5% for most variables). Significant correlations between Taekwondo Anaerobic Intermittent Kick Test, Wingate anaerobic test, and jumping tests' variables were mostly "large". Elite taekwondo athletes showed greater taekwondo test performances compared with their sub-elite counterparts (p < 0.001). Receiving operating characteristic analysis indicated that the taekwondo specific test was able to effectively discriminate between elite and sub-elite taekwondo athletes. Overall, the findings of the current study support the concurrent validity of the Taekwondo Anaerobic Intermittent Kick Test. In particular, the Taekwondo Anaerobic Intermittent Kick Test showed good ability to effectively discriminate between taekwondo athletes of different competitive levels
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