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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Tapering for Strength-Power Individual Event and Team Sport Athletes

Bazyler, Caleb 01 August 2016 (has links)
The overall purpose of this dissertation was to address mechanistic and performance changes following a peaking phase in individual event and team sport strength-power athletes. This purpose was addressed by conducting 4 separate investigations with track and field athletes, volleyball athletes, and a national level weightlifter. The following are the primary findings from these investigations. Division I collegiate throwers increased competition throwing performance, jumping performance, and preserved muscle architecture characteristics following an overreach and taper. There were moderate decreases in division I female collegiate volleyball athlete’s vastus lateralis muscle thickness with no statistical changes in jumping performance following a taper with no prior overreach in. There were moderate to very large differences in countermovement jump height supercompensation during the peaking phase in favor of the returners over the new players on a similar team of female volleyball athletes. Changes in serum concentrations of inflammatory, hypertrophic and endocrine markers corresponded with alterations in training volume-load and partially explained changes in jump, dynamic mid-thigh pull, and weightlifting performance following multiple competition phases in a national level weightlifter. Additionally, vastus lateralis cross-sectional area can be maintained following a competition phase in a high level weightlifter provided large changes in body mass are not attempted close to competition. The findings of these investigations support the use of overreach and tapering for strength-power athletes and provide an underlying biochemical, morphological, and biomechanical basis for the observed changes in performance.
132

RELATIVE CROSS TRACK ERROR CALCULATIONS IN ASABE/ISO 12188-2:2012 AND POWER/ENERGY ANALYSIS USING A 20 HP TRACTOR ON A FULLY ELECTRIC DRIVETRAIN

Rounsaville, Joseph D. 01 January 2017 (has links)
ASABE/ISO Standard 12188-2 provides test procedures for positioning and guidance systems in agricultural vehicles during straight and level travel. The standard provides excellent descriptions of test procedures, however it does not provide detail on methods to carry out the calculations necessary to calculate relative cross-track error (XTE), which is the primary measurement used to judge accuracy of the system. The standard was used to estimate the guidance accuracy of a relatively low-accuracy vehicle at 1.25 and 0.5 m s-1. At 1.25 m s-1, a nearest point calculation overestimated mean XTE by 0.8 cm, or 8.2%. The location sampling density was much higher with a 0.5 m s-1 travel speed, and mean XTE was only overestimated by 0.1 cm with the nearest point method. Power and energy data were recorded using a sled with a known weight to vary the drawbar force on asphalt. This will allow a comparison between the electric and conventional tractor over a range of forces applicable to a 20 HP tractor. The electric tractor was found to consume less than half the energy compared to a Kubota L5030 in a common configuration and a custom configuration to match the weight distribution of the electric tractor. Finger weeding tasks were recorded throughout the year capturing the duration and frequency of these tasks at the University of Kentucky (UK) consumer supported agriculture (CSA) farm. Power and energy data were recorded from the electric tractor while finger weeding. Diesel consumption was also recorded from a conventional tractor while finger weeding. Field data shows that the electric tractor needs approximately 0.532 kWh of energy while a conventional tractor requires approximately 1.258 kWh or energy to finger weed each row of vegetables. Conventional electric bills were compiled for the University of Kentucky CSA establishing an average monthly electric need. Historic NREL data was compiled establishing an average potential solar resource for central Kentucky. It was determined that a 15 kW photovoltaic array could meet the conventional electric needs of the UK CSA and supply the net energy allowing the electric tractor to meet the finger weeding need.
133

A History of the Athletic Career of E. L. "Dick" Romney

Boothe, Ray Merrill 01 May 1958 (has links)
Ernest Lowell ("Dick") Romney chose athletics as a career, believing that it was worth-while for himself and for those with whom he would work and teach. He has devoted his entire life to this endeavor and through his many achievements has become one of the most prominent and respected men in his profession. He stands as an example of high ideals and his name is a legend in the Rocky Mountain area. Placed between Rockne and Roper, in the Football Hall of Fame at Rutgers University in New Jersey, is the name of Romney, E. L. "Dick". Other coaches so honored are Fielding H. Yost, Amos Alonzo Stagg, Fritz Crisler, and Frank Cavanaugh. Included in the roster of famous players are Harold ("Red") Grange, James Thorpe, George Gipp, Bronco Nagurski, Stanley Barnes, and Donald Hutson. The work of these men personifies the contributions of football in the American way of life. Their names and accomplishments serve as beacons for the young men of today. Nothing could be more fitting than for E. L. Romney to be honored along with all of the above mentioned people. It is a well deserved climax to an illustrious career. However, Dick has not retired from his chosen field. In 1949 he was appointed Commissioner of the Mountain States Athletic Conference. At present his wisdom is guiding the athletic destinies of eight universities in the states of Utah, Wyoming, Montana ,Colorado, and New Mexico.
134

Ground Reaction Forces Through a Range of Speeds in Steeplechase Hurdling

Tracy, James Brian 01 August 2017 (has links)
The men's steeplechase event requires participants to jump over thirty-five 0.914-meter-tall obstacles, 4 rigid barriers and 1 fixed barrier followed by a 3.66-meter-long water pit per lap, over a 3000-meter distance. This study investigated the effect of increasing running velocity, through a range of 5.33 m/s to 6.66 m/s, on takeoff and landing ground reaction forces, for males during steeplechase hurdling using a force plate embedded under a track surface. Subjects completed 1 trial within each of 6 different pace ranges in a random order, once with a hurdle following the force plate to measure the takeoff ground reaction forces and a second time with the hurdle prior to the force plate to measure the landing ground reaction forces. Within a repeated measures linear mixed model during takeoff, peak vertical force (r2 = 0.1968, p < 0.01) and horizontal propulsive impulse (r2 = 0.0287, p = 0.02) were positively correlated with increasing velocity, and ground time (r2 = 0.1904, p < 0.01) was negatively correlated with increasing velocity. Within a repeated measures linear mixed model during landing, vertical impact force loading rate (r2 = 0.0099, p < 0.01) was positively correlated with increasing velocity and ground time (r2 = 0.2889, p < 0.01), vertical impulse (r2 = 0.1704, p = 0.02), and horizontal braking impulse (r2 = 0.0004, p = 0.05) were negatively correlated with increasing velocity. As male steeplechasers prepared to hurdle at increasing speeds, they produced a greater peak vertical force on the takeoff step while decreasing the ground time during takeoff, and increasing the horizontal propulsive impulse to carry themselves beyond the hurdle. While landing from the hurdle at increasing speeds, the athlete decreased the amount of time spent on the landing stance and the vertical impulse, and increased the magnitude of horizontal braking impulse and vertical loading rate. The relationships of these variables: takeoff peak vertical force, takeoff ground time, takeoff horizontal impulse, landing ground time, and landing vertical loading rate to increasing velocity were all comparable to overground running responses. The data differed from running by not indicating any change in hurdling takeoff horizontal braking impulse; however, the horizontal braking impulse did increase on hurdling landing. It was expected to decrease on hurdling landing due to the foot landing more underneath the center of mass after hurdling compared to running. The decrease in landing vertical impulse as speed increased also differed from normal running steps. We suggest that further research include kinematic measures to better understand the relationship between these variables as hurdling velocity increases.
135

Physiological and Performance characteristics of Elite Mountain Bike Cyclists

Linaker, Kelly, n/a January 2004 (has links)
Cross-country (XC) mountain bike (MTB) riding is a new cycling discipline and research examining the physiological demands of MTB racing is limited. The purpose of this study was to comprehensively measure physiological characteristics, to identify the performance demands of XC and time trial (TT) MTB racing and to simulate a field MTB race in the laboratory to measure the physiological responses associated with racing. Twelve male and four female elite MTB cyclists volunteered to take part in this study. Subjects completed maximal aerobic power and, anaerobic power and capacity tests. MTB race data was collected during TT and XC competitions with SRM MTB power cranks fitted to the subjects MTB. Five male MTB cyclists (V . O2max 72.0 +/- 4.6 ml/kg/min-1, maximum power output (MPO) 5.40 +/- 0.30 W/kg-1, maximum heart rate (HRmax) 189 +/- 7 bpm) performed two laps of a MTB course in the field using their race bikes with MTB SRM power cranks fitted. A laboratory MTB race simulation was performed using a wind braked ergometer. Cyclists attempted to match the average and peak power output (W/kg-1) achieved in the field trial in the laboratory. Power output (PO), heart rate (HR) and cadence (revolutions per minute, rpm) were measured during field and laboratory trials, while oxygen uptake (V . O2) was determined only during the laboratory simulation. Results showed TT MTB racing is significantly shorter in duration and distance than XC racing and significantly higher for power output and heart rate, with more time spent above anaerobic threshold (16.0 +/- 2.4 and 22.8 +/- 4.3% time) and MPO (38.4 +/- 5.2 and 26.5 +/- 9.4% time) than XC racing (p<0.05). Mean power output and heart rate between the field and laboratory trials were similar (4.18 +/- 0.55 and 4.17 +/- 0.15 W/kg-1 respectively, 175 +/- 9 and 170 +/- 8 bpm). Time spent below 2 W/kg-1 and above 6 W/kg-1 for the field and laboratory trials accounted for ~32% and ~30% of the total time, respectively. During field and laboratory trials, cyclists utilised 77.8 and 77.3% of MPO, 93 and 90% of HRmax, respectively. There was a significant difference between mean cadence in the field and laboratory trials (60.3 +/- 9.1 and 75.2 +/- 7.0 rpm, respectively, p<0.05). The cadence band of 60-69 rpm showed a significant difference between the time spent in that band from the field (14.6%) to the laboratory (4.6%). The time spent above a cadence of 80 rpm in the field was 29.8% compared to the laboratory at 62.0% of the time. Mean and peak V . O2 for the simulation was 57.5 +/- 3.3 and 69.3 +/- 4.4 ml/kg-1/min-1 respectively, with cyclists sustaining an average of ~80% V . O2max. In summary, MTB competition requires multiple short-high intensity efforts and places high demands on both the aerobic and anaerobic energy systems. The power output and heart rate responses to a MTB field race are similar when simulated in the laboratory, although in the laboratory higher cadences are selected for the higher power outputs than the field.
136

The effect of music and no music on pre-performance arousal, perceptions of performance exertion and pain, and evaluations of performance in high school track runners

Todd, Melissa Lee, Brown, Chrisanthia, January 2006 (has links)
Thesis (Ph. D.)--School of Education. University of Missouri--Kansas City, 2006. / "A dissertation in counseling psychology." Advisor: Chris Brown. Typescript. Vita. Title from "catalog record" of the print edition Description based on contents viewed Nov. 9, 2007. Includes bibliographical references (leaves 98-105). Online version of the print edition.
137

Le bilan hydrologique régional: étude de sa variabilité à l'aide de simulations numériques

De smedt, Sylvie 01 1900 (has links) (PDF)
A l'occasion de ce travail de thèse, nous avons souhaité contribuer aux études d'impacts du changement climatique sur le bilan d'eau en Europe. Nous avons utilisé les outils de la modélisation du climat, modèle de circulation générale et schéma de surface, et nous nous sommes placés à l'interface entre l'atmosphère et la surface. Ce travail s'est décomposé en deux parties. Dans un premier temps, nous avons étudié la sensibilité du bilan d'eau simulé par le schéma de surface du laboratoire, ORCHIDEE, à la résolution des forçages atmosphériques sur deux régions d'Europe, la péninsule ibérique et le bassin versant du Rhône (dans le cadre du projet international Rhône-AGG). Dans un deuxième temps, nous avons abordé la thématique des impacts du changement climatique sur le bilan d'eau sous un angle plus atmosphérique, par l'étude des dépressions qui traversent l'Atlantique en direction de l'Europe, et de leurs liens avec les précipitations.
138

The effect of selected buffering agents on performance in the competitive 1600 meter run

Avedisian, Lori-Ann 01 May 1995 (has links)
Graduation date: 1995
139

Countermeasures against railway ground and track vibrations

Hildebrand, Robert January 2001 (has links)
Railway track and ground vibrations are considered, with anemphasis on methods of mitigation ("countermeasures"), forapplication to wayside disturbance problems. Original field measurements from two sites in Sweden, aswell as borrowed measurements from Norway, provide vibrationresults at many points on the track, on and underneath theground surface, for a variety of trains, both with and withoutcountermeasures in-place. Infinite periodic system theory is the basis of track-onlyand track-ground interaction models presented. The repeatingelement includes the sleeper, pad-fastener, rail, and either alocally-reacting ballast or a continuous ballast-soilwaveguide. The track-only model is even refined for nonlinearand high-frequency cases. The models are suitable for studyingcountermeasures in the track, or in the foundation(soil-stabilization). This latter countermeasure is shown to beeffective at low frequencies (of geotechnical interest), butsometimes counterproductive at audible frequencies (disturbanceproblems). An analytical model for hard seismic screens is alsopresented, to complement the treatment of ground vibrationcountermeasures; this is based on physical approximations whichare favored by "high" (i.e, audible)frequencies and softsoils. Notably, experimentally observed resonant behavior isexplained. <b>Keywords:</b>ground vibration, vibration screen, trackvibration, railway vibration
140

The intonational grammar of Persian

Sadat-Tehrani, Nima 21 September 2007 (has links)
This thesis is a detailed investigation of the phonology and phonetics of the intonation of Persian carried out in the framework of the AM theory of intonational phonology. Based on 2112 utterances read by a total of 8 native speakers, the work, on the one hand, presents a phonological account of the prosodic structure of this language, a structure that consists of the level Accentual Phrase with the pitch accent (L+)H* immediately dominated by the level Intonational Phrase, each level being marked by a low or high boundary tone. On the other hand, it scrutinizes the phonetic implementation of tones with regard to segments and shows how the phonology of Persian intonation is phonetically realized in the speech string. This research also studies the intonational patterns of simplex sentences, compound sentences coordinated with different types of conjunctions, subordinate structures, and vocative constructions. The sentence types include copular verb declaratives, sentences with unaccusative and unergative verbs, (S)(O)V sentences with and without adjuncts, null subject sentences, scrambled sentences, yes/no questions, leading yes/no questions, alternative questions, tag questions, single and multiple WH-questions, echo questions, imperatives, and single, double, and phrase focus constructions. / February 2008

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