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Full-Text Articles in Life Sciences

A New Approach To Modeling Vertical Stiffness In Heel-Toe Distance Runners, Iain Hunter Dec 2003

A New Approach To Modeling Vertical Stiffness In Heel-Toe Distance Runners, Iain Hunter

Faculty Publications

Various models have been used to describe distance running technique. Among these, the mass-spring model is fairly simple to use and apply, but when employed as a model, does not predict vertical force accurately especially when a heel strike is exhibited. The purpose of this article is to demonstrate how the mass-spring model can be modified to provide a simple, yet accurate prediction of ground reaction forces in distance running. Sixteen subjects ran on a force instrumented treadmill. Vertical forces during running at a self-selected pace were collected at 500 Hz. Vertical stiffness was calculated using the conventional mass-spring model …


Simulation Of Fixed– And Variable–Rate Application Of Granular Materials, John Patrick Fulton, Scott A. Shearer, Timothy S. Stombaugh, Michael E. Anderson, Thomas F. Burks, Stephen F. Higgins Sep 2003

Simulation Of Fixed– And Variable–Rate Application Of Granular Materials, John Patrick Fulton, Scott A. Shearer, Timothy S. Stombaugh, Michael E. Anderson, Thomas F. Burks, Stephen F. Higgins

Biosystems and Agricultural Engineering Faculty Publications

Research has shown that application errors exist with variable–rate technology (VRT) systems. Consequently, using prescription maps for economic and agronomic analyses can generate misleading results. The intent of this article was to develop and validate a spatial data model for generating “as–applied” maps to support the advancement of precision agriculture practices. Previous research modified ASAE Standard S341.2 to include a 2–D matrix of collection pans to assess fixed–rate and variable–rate (VR) deposition of granular fertilizers and agricultural lime from a spinner disc spreader. The “as–applied” spatial data model uses GIS functionality to generate “as–applied” surfaces by merging distribution patterns and …


Local And Deep-Ocean Forcing Contributions To Anomalous Water Properties On The West Florida Shelf, Robert H. Weisberg, Ruoying He Jun 2003

Local And Deep-Ocean Forcing Contributions To Anomalous Water Properties On The West Florida Shelf, Robert H. Weisberg, Ruoying He

Marine Science Faculty Publications

Material property distributions on continental shelves result from the mixing and modifications of estuarine and deep-ocean source waters. How this occurs depends on the momentum and buoyancy that are input either locally on the shelf or from the deep-ocean at the shelf break. We address this question of local versus deep-ocean forcing for the West Florida Shelf (WFS) using in situ data and a numerical circulation model. The spring and summer seasons of 1998 and 1999 show distinctively different water properties on the shelf and at the shelf break. We account for these differences by a combination of local forcing, …


Diurnal Variation In The Basal Emission Rate Of Isoprene, Jennifer L. Funk, Clive G. Jones, Christine J. Baker, Heather M. Fuller, Christian P. Giardina, Manuel T. Lerdau Jan 2003

Diurnal Variation In The Basal Emission Rate Of Isoprene, Jennifer L. Funk, Clive G. Jones, Christine J. Baker, Heather M. Fuller, Christian P. Giardina, Manuel T. Lerdau

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Isoprene is emitted from numerous plant species and profoundly influences tropospheric chemistry. Due to the short lifetime of isoprene in the atmosphere, developing an understanding of emission patterns at small time scales is essential for modeling regional atmospheric chemistry processes. Previous studies suggest that diurnal fluctuations in isoprene emission may be substantial, leading to inaccuracies in emission estimates at larger scales. We examined diurnal patterns in the basal emission rate of isoprene in red oak (Quercus rubra), eastern cottonwood (Populus deltoides), and eucalyptus (Eucalyptus saligna) and the influence of light and temperature on the magnitude of these diurnal patterns. Maximum …