Optimization of an automated FI-FT-IR procedure for the determination of o-xylene, toluene and ethyl benzene in n-hexane

The development and optimization of an automated flow injection (FI) manifold coupled with a Fourier transform infrared (FT-IR) detector for the determination of toluene, ethyl benzene and o-xylene in an n-hexane matrix is described. FT-IR parameters optimized were resolution and number of co-added scans; FI parameters optimized were type of pump tubing, carrier flow rate and sample volume. ATR and transmission flow cells were compared for the determination of o-xylene, the ATR cell was easier to use and gave better figures of merit, except for sensitivity, for which the transmission cell was twice as good. Multivariate calibration routines were applied to the FI-FT-IR data and the PLS1 algorithm gave relative root mean standard errors of crossvalidation (RRMSECVs) < 7% for all three analytes using mean-centred data and the first derivative for o-xylene

The observational analysis of elite coaches within youth soccer: The importance of performance analysis

The study investigated the observational capabilities of experienced elite coaches whilst focusing upon soccer specific actions and playing positions within elite youth soccer. Six soccer coaches assessed the performances of 10 youth soccer players (across 8 matches) on their short/long passing, tackling, shooting, heading and dribbling. Analysis was undertaken on an overall, quality and positional grouping basis. Mean observational accuracy was 38.8%, with successful shooting (78.6%) and passing (29.9%) illustrating the range. The limited effective observation of dribbling (37.2%), often considered a separating factor within talent identification, highlights the need for objective measures to aid such processes. Positional grouping analysis elicited 20% more effective observation for unsuccessful compared with successful actions. The poor level of observational accuracy identified herein has significant implications on talent identification assessments devoid of post-performance analyses. The findings reinforce the importance of performance analysis in the provision of highly accurate and comprehensive augmented feedback within the coaching process

FORCE GENERATION AT THE GOLF SHOE SOLE TO GRASS TURF INTERFACE OCCURRING WITH ALTERNATIVE SPIKE DESIGNS.

Forces were measured at the golf shoe sole to natural turf interface while eight low handicap golfers performed distance shots with a driver. Two types of golf shoe were worn. Forces were analysed using two Kistler force platforms and measures of maximum vertical force and the amount of force generated in the vertical, anterior and posterior, and medial-lateral planes showed similar values for the two shoes but with forces at the front foot greater than those for the back foot. At the back foot the torque (Tz) range generated was notably significantly greater at a mean 17.58 Nm for the shoe design based on 7 spikes than for the shoe design based on 6 spikes for which a mean Tz of 14.82 Nm was recorded (

Density Fluctuations in Stochastic Kinematic Flows

At the macroscopic scale, many important models of collective motion fall into the class of kinematic flows for which both velocity and diffusion terms depend only on particle density. When total particle numbers are fixed and finite, simulations of corresponding microscopic dynamics exhibit stochastic effects which can induce a variety of interesting behaviours not present in the large system limit. In this article we undertake a systematic examination of finite-size fluctuations in a general class of particle models whose statistics correspond to those of stochastic kinematic flows. Doing so, we are able to characterise phenomena including: quasi-jams in models of traffic flow; stochastic pattern formation amongst spatially-coupled oscillators; anomalous bulk sub-diffusion in porous media; and travelling wave fluctuations in a model of bacterial swarming.Comment: 21 pages, 4 figures, fixed typo

INFLUENCES OF GOLF CLUB SELECTION ON GROUND REACTION FORCES ON A NATURAL GRASS SURFACE

Ground reaction forces were measured on natural turf at both feet during the golf swing using a driver and a 3-iron. Sixteen male golfers, with handicaps 0-14, performed 5 shots with each club while wearing a golf shoe with an alternative spike design. The front foot forces were greater than the back foot forces in all three orthogonal planes. At the front foot the maximum vertical force (Fz) generated was much greater when using the 3 iron by approximately 50%. The mean Fz range was greater when using the 3 iron of approximately 1.2 BW compared to 0.79 BW when using the driver. The back foot mean maximal Fz force generated was again greater for the 3 iron by 59% and mean Fz range approximately twice as great as compared to when using the driver. The Fx medial lateral force generated at the back foot was 60% greater when using the 3 iron

Biomechanical assessment of the shoe-surfact interface during the golf swing

A successful golf swing is dependent on the performance of a complex sequential action. This movement involves the feet, knees, rotation of the hips and trunk, which result in a transmission of forces and torques between the feet/shoes and the ground (Williams and Sih, 1998). The aim of this thesis was to investigate golf shoe interface aspects relevant to the golf swing process. One flat-soled, one traditional and three alternative spiked golf shoe sole interfaces were evaluated. Using a mechanical traction-testing device, specific linear forces and rotational torques were applied to the forefoot and whole-foot of the five different golf shoe sole interface designs on a grass covered force platform. Greater linear and rotational ground action forces were identified within the traditional sole (whole-foot limiting friction 1.01) and alternative sole conditions (whole-foot limiting friction Blue 1.00, Red 1.02, Yellow 1.01) when compared to a flat-soled shoe (whole-foot limiting friction 0.88). The traditional shoe was also identified to frequently produce greater friction (forefoot limiting friction 0.97) in comparison to the alternative shoe soles (forefoot limiting friction Blue 0.92, Red 0.91, Yellow 0.91). Due to the mechanical nature of the study it was important to gain an understanding of how the golf shoe sole interface interacted with the ground and if between-shoe differences were repeated when subjected to dynamic human movement during the golf swing. Dynamic analysis of the five soles identified two between shoe-sole differences (P = <.OS); Driver back foot Tz range (BW.m) (Traditional shoe (IS.98 ± 1.11) was significantly different to the Blue alternative (12.77 ± .83) and flat-soled shoe (12.73 ± .8S)); and 7iron front foot, Mz maximum time (s) (Flat-soled shoe (1.39 ± .02) was significantly different to Blue (1.72 ± .03) Red (1.71 ± .03) and Yellow (1.72 ± .04) alternative spiked shoes). The low handicap group (0-7) produced significantly slower weight transfer times (s) when compared to the medium (8-14) and high (15+) groups within all club conditions (3iron Low 0.73 ± .03, Medium 0.43 ± .02 and High 0.41 ± .02; 7iron Low 0.76 ± .01 Medium 0.S4 ± .01 and High 0.54 ± .01; Driver Low 0.70 ± .01, Medium 0.48 ± .01 and High 0.43 ± .01). However, no significant differences in forces or torques were identified between handicap groups. The findings contradict the previous mechanical testing results concluding mechanical traction tests are not an appropriate test of between shoe differences when relating the findings to the golf swing. The differences in forces created between the shoe and ground identified between the mechanical and dynamic studies was a result of the adaptation by the golfer to the footwear condition. Dynamic in-shoe pressure analysis identified regional pressures created between the golfer and shoe throughout the swing process. The highest peak pressures (N/cm2 ) were associated with the lateral regions of the front-foot from the point of ball impact (Front foot Traditional (R5) 114.33 ± 6.29 N/cm2 Back foot Traditional (R5) 7.18 ± 1.07 N/cm2) supporting previous kinematic and ground action force findings. The traditional spiked shoe produced greater in-shoe pressures within the front foot lateral mid-foot region however all sole conditions provided significantly higher pressures within specific in-shoe regions at different stages of the swing process. The comparable between shoe findings support the previous dynamic findings. The thesis enhanced current understanding of between shoe-ground and shoe-golfer interactions. Different demands were placed on the front and back shoes during the golf swing highlighting the need for asymmetrical shoe sole designs. Limited differences were identified between the different shoe sole interface designs, concluding that golf shoe interface designs are not effective for the demands of the golf swing, subsequently shoe outsole modifications were suggested.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Track cycling: An analysis of the pacing strategies employed during the devil elimination race

This study aimed to provide a description of the pacing requirements of the track cycling Elimination race, and to identify effective pacing strategies to maximise overall Omnium medal opportunity. Six male, and six female elite competitive races were investigated using half-lap split times. Selected dependant variables were; mean speed and variation in speed. Spearman’s Rho correlations were used to test patterns between dependant variables and the final finishing position of riders. One-way ANOVAs were also applied to test for differences in dependant variables, between successful (top 6 finishers) and unsuccessful groups (7th-12th). Pacing patterns of the men's and women's races were complex, but followed an overall positive and variable pacing pattern, with men's race quarter speeds of 52.8km/h (±1.9), 52.1km/h (±2.1), 51.1km/h (±2.2), and 49.5km/h (±5.5). In general, differences in pacing strategy were not found to significantly influence the success of riders unless employed late in the race. Results are discussed for the application and the development of effective elimination race strategies and tactics

Performance characteristics of a low-cost, field-deployable miniature CCD spectrometer

Miniature spectrometers incorporating array detectors are becoming a viable, low-cost option for field and process deployments. The performance characteristics of one such instrument are reported and compared with those of a conventional benchtop instrument. The parameters investigated were wavelength repeatability, photometric linearity, instrumental noise (photometric precision) and instrumental drift