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DOUBLE AND TRIPLE BOUNCING SPINNING SOCCER BALL
Get PDFThe trajectories of soccer ball penalty kicks that strike one of the goal-posts while rolling along the surface are simulated and analyzed using conservation of linear and angular momenta. The reflected trajectories upon collisions with the goalpost are calculated and used to determine whether double or triple bounces take place. The analysis is iterated for a range of initial launch speeds, angular velocities, and normal and tangential coefficients of restitution of the goalpost-ball collisions. It is observed that double bounces can take place for almost any combination of the above parameters if the soccer ball strikes the appropriate narrow sectors of the first goalpost. The corresponding parameter ranges and impact areas are considerably more restricted for generating triple bounces. The angular velocity and coefficients of restitution are found to significantly influence the occurrence of multiple bounces
REACTION RATES TO VISUAL AND AUDITORY STIMULI IN NCAA BASEBALL PLAYERS**
No full textBaseball is a sport that requires quick reflexes and fast reaction times in order to be successful. Players have to be able to make split decisions on how to react to the baseball and make the right play in the game as quickly as possible. In this study we examined the reaction times to visual and auditory signals in The Young Harris College NCAA baseball players with the hypothesis that field position will be associated with differences in reaction rates. We used the iWORX software (LabScribe) to determine each participant’s reaction times (hand and foot) to both visual and auditory stimuli. Thus, four types of reaction rates were measured for each participant: Eye-Hand, Eye-Foot, Ear-Hand and Ear-Foot reaction times. Each type of reaction time was scored 10 times in a given trial. All data have been collected and data analysis is currently underway
Size Estimates of Extinct Aquatic Snakes from the Eocene of Central Georgia
No full textThe purpose of this study was to estimate the total length of extinct aquatic marine palaeopheid snakes based on fossil vertebrae recovered from Eocene sediments in an active kaolin mine in Wilkinson County, Georgia. Across portions of central Georgia, extensive deposits of kaolin lie immediately beneath the sediments of the Barnwell Group, and mining operations to recover kaolin often expose these fossil-bearing sediments. The snake fossils were recovered by surface collecting fossiliferous horizons exposed by mining operations. In addition to fossil snakes, fossils of many sharks, sawfish and rays, turtles, and some larger marine mammals were also recovered. A comparison of the Wilkinson County mine fossils with the nearby Hardie Mine fauna suggests a comparable Late Eocene (34.5-35.5 ma) age. Using digital calipers, anterior-posterior centrum lengths were taken on vertebrae of modern boids (Boa, Liasis, and Python) and the colubrid genus Pantherophis of known lengths. Regression analyses were performed for the modern snakes, and a strong correlation between centrum length and total body length was found for Boa (r2 = 0.977) and Pantherophis (r2 = 0.710). Using the regression equations, the estimated total body length of the ancient sea snakes ranged between 1.6 and 4.8 meters with the Boa regression and from 1.9 to 5.6 meters for the Pantherophis regression. Although not directly related to the modern sea snake, the ancient palaeopheid sea snakes were up to 4 meters longer than modern sea snakes. This analysis enhances our understanding of the diversity of ancient snakes that once lived in Georgi
Development of a Connected Vehicle Technology in the City of Valdosta**
No full textA team of researchers from Valdosta State University (VSU) and Georgia Tech (GT) have been working on a smart community project in collaboration with the city of Valdosta and two technology industries (Applied Information and Temple) to develop a connected vehicle smart system in all 128 intersections in the city of Valdosta. This one-year study will allow the City of Valdosta and its communities in the Lowndes county areas to develop a smart and connected traffic monitoring system to improve the movement of all types of vehicles and pedestrians in a safe and efficient manner. Using the funding from Georgia Tech’s Georgia Smart Communities Initiatives we are developing a more sophisticated Traffic Monitoring Center (TMC) and involving VSU engineering students in experiential learning and and undergraduate research to gain valuable training and experience related to smart systems in traffic management. The smart system will incorporate the Travelsafely App to apply preemption for the ten fire trucks, so that they can move easily through the intersections. The App will also provide the capabilities to notify drivers about bicycle riders, pedestrians, and others drivers and motorists in the area. Also notifications will be given to the drivers that are in the school or other speed zones about the changes in traffic lights. Furthermore, if a driver is about to run a red light, the App will give him/her a warning. We have made some progress related to the installation of the hardware in the cabinets of a few traffic lights and expect that it will be completed by the mid-spring in most signalized intersections. This study will describe the advance technology used and the recent results obtained from the smart city project program in Valdosta
THE EFFECTS OF MICROPLASTICS ON SEA URCHIN LARVAL SURVIVORSHIP AND DEVELOPMENT**
No full textMicroplastics, plastic pieces smaller than five millimeters, are of growing concerns in marine ecosystems because they cause multiple negative effects, including decreased survivorship and direct developmental defects. Sea urchin larvae are a target for microplastic studies because they easily ingest microplastics and are an important component of marine zooplankton communities. Prior studies examining the survival and development of Tripneustes gratilla larvae exposed to 5µm polyethylene beads found no effect on larval survivorship and limited effects on body width development at five days post feeding (dpf). However, it is unclear how generalizable these findings are to other sea urchin species and for other types of plastic. Our research aims to understand the effects of polystyrene microplastics on larval survivorship and body-size development in Lytechinus variegatus and Arbacia punctulata following similar procedures as used with T. gratilla. In this study, L. variegatus and A. punctulata larvae were divided among three treatments that varied in microplastic concentration but were consistent in total particle concentration. The treatments were 1) 300 algae/ml; 2) 150 algae and 150 5μm polystyrene beads/ml; 3) 300 5µm polystyrene beads/ml. Larvae were kept at a concentration of 5 larvae/ml for all treatments. Percent survivorship was estimated from 5ml samples taken daily until survivorship was around zero. Body measurements were taken at 5 dpf for both species and 9 dpf for just A. punctulata larvae. Five different body measurements were made: post-oral arm length (POA), body width, body length, the ratio of POA length to body width, and the ratio of POA length to body length. Current results suggest that for L. variegatus there is lower survivorship in the treatments with beads relative to the 300 algae/ml treatment, but replication is needed for statistical analysis. Survivorship for A. punctulata was statistically lower in the treatments with beads at 5 dpf. For both species, initial results suggest limited effects on body measurements, but replication is needed. So far, our results suggest that it may be a general trend among sea urchin larvae that there are limited effects of microplastics on development, but microplastics have a larger effect on larval survivorship
RESEARCH TO ESTABLISH IF THE LEVELS OF NITRITE IN LAKE CHATUGE ARE IN A DEPENDENT RELATIONSHIP WITH THE LEVELS OF POLLUTION**
No full textThe main purpose of this research was to evaluate nitrite levels at six different locations of Lake Chatuge and to examine its dependency on priority levels of pollution. Water samples were collected three times from six designated locations on three different days. Nitrite levels were determined through the standard addition method by adding an increasing amount of nitrite standard to a water sample. The nitrite levels in the water samples will be compared with levels of pollution in Chatuge Lake to find if there is a correlation between the level of nitrite and septic leaks. The variance of the nitrite level may help determine the severity of pollution at different locations
ECONOMIC DESIGN OF A MICROWAVE ABSORBER
No full textIf a microwave absorber is designed to absorb a particular frequency, then absorber material’s thickness and complex dielectric constant must have to have particular value for impedance matching between absorber and free space. But the combination of these two parameters might not be found in materials available in the marketplace and costumed-synthesized material might be too much expensive. In this research, material thickness is engineered by introducing an air gap in the absorber structure and best possible impedance matching is achieved by tuning the thickness of the air gap. The state-of-the-art 3D electromagnetic software HFSS is used to determine the appropriate thickness of the air gap. Finally, the frequency response of the designed absorber is explained by transmission line theory
APPLICATION OF METAMATERIAL IN BLOCKING UNWANTED MICROWAVE SIGNALS
No full textPropagation of plain electromagnetic wave can be explained by distributed transmission line theory or parallel plate waveguide theory. Whether it is transmission line or parallel plate waveguide, introduction of a shunt impedance containing L-C series circuit, should exhibit a “Band Stop” frequency response with a center frequency as determined by the resonance condition of the L-C series circuit. In this research, a 3D electromagnetic simulation is conducted with ANSYS HFSS commercial software to model a medium containing short and thin metal strips arranged in 3D periodic fashion to realize L-C series circuits evenly distributed throughout the medium. Simulation result demonstrates a “Band Stop” behavior of the composite material as predicted and shifting of “Band Stop” response to 5G radiation range is accomplished by varying the length and periodicity of the metal strip. Finally, “Band Stop” behavior and it’s shifting with respect to frequency are explained by using transmission line theory
Modeling Blended Absorption Troughs in NGC3783
No full textWe have analyzed the CIV absorption troughs in spectra of the Seyfert galaxy NGC3783 taken by the Hubble Space Telescope. Using a novel approach, we have developed a method to explore the absorption in blended absorption troughs to simultaneously determine the covering fractions and optical depths of individual outflows. We find that the troughs in NGC3783 can be modeled with two outflows that have covering fractions close to 100% and large optical depths suggesting that the troughs are saturated. We also show that the covering fraction of the individual outflows changed significantly over a 15 year period
Detecting UFOs in FUSE Spectra of Seyfert Galaxies
No full textWe have searched the spectra of 72 low redshift (z \u3c 0.15) for absorption troughs due to OVI and hydrogen at high velocities in an attempt to find so-called ultra-fast outflows, which have been detected in x-ray spectra of similar objects. In the survey, we have found 1 object with a potential trough. This could suggest that the material responsible for ultra-fast outflows is too highly ionized to exhibit absorption troughs of OVI. This has significant implications for modeling the formation of ultra-fast outflow troughs