Relationship between impact characteristics and launch direction in softball hitting: A study involving elite players

In the game of softball, the batter should possess the necessary skills to hit the ball toward various directions with high initial speed. However, because various factors influence each other, there are limitations to the range that can be controlled by the batter’s skill. This study was aimed at extracting the impact characteristics associated with the launch speed/direction and batted ball spin and clarifying the important skills required to improve the batter’s hitting performance. In our experiments, 20 female softball players, who are members of the Japan women’s national softball team, hit balls launched from a pitching machine. The movements of the ball and bat before, during, or after the impact were recorded using a motion capture system. Stepwise multiple regression analysis was performed to extract factors relating the side spin rate. The undercut angle (elevation angle between the bat’s trajectory and the common normal between the ball and bat: ΔR2 = 0.560) and the horizontal bat angle (azimuth of bat’s long axis at ball impact: ΔR2 = 0.299) were strongly associated with the side spin rate (total R2 = 0.893, p < 0.001). The undercut angle in opposite-field hitting was significantly larger than that in pull-side hitting (p < 0.001). The side spin rate was associated with the undercut angle because the bat’s distal (barrel) side inclined downward (–29.6 ± 8.7°) at impact. The ball exit velocity was higher when it was hit at a smaller undercut angle (R2 = 0.523, p < 0.001). Therefore, it is deemed desirable to focus on maximizing the ball exit velocity rather than ball spin because the ball–bat impact characteristics vary inevitably depending on the launch direction. Meanwhile, the use of the ball delivery machine and the slower pitched ball are the limiting factors in the generalization of the findings.

Recovery and effective utilization of waste heat from the exhaust of internal combustion engines for cooling applications using ANSYS

The exhaust gases from an internal combustion (IC) engine carry away about 75% of the heat energy which means only 25% of heat energy is operated for power production. A recovery unit at the exhaust outlet port can ensure heat exchange between different temperature fluids through conjugate heat transfer phenomena. This study represents heat recovery from exhaust gases that are emitted from IC engines which can be utilized in various applications such as vapor absorption refrigeration systems. In the present work, a new type of perforated fin heat exchanger for waste heat recovery of exhaust gases is designed using SolidWorks, and the flow field design of the heat recovery system is optimized using ANSYS software. Various parameters (velocity, pressure, temperature, and heat conduction) of hot and cold fluid have been analyzed. Inlet velocity of cold fluids including refrigerant (LiBr solution), water, and graphene oxide (GO) nanofluid have been adopted at 0.03 m/s, 0.165 m/s, and 0.3 m/s, respectively. Inlet velocity of hot fluid is taken as 2 m/s, 4 m/s, and 6 m/s, respectively, to develop a test matrix. The results showed that maximum temperature reduction by the exhaust is achieved at 104.8°C using graphene oxide nanofluids with an inlet velocity of 0.3 m/s and exit velocity of 2 m/s in the heat recovery unit. Similarly, temperature reduction by exhaust gases is acquired at 102 °C using water and 96.34 °C by using a refrigerant (LiBr solution) with the same exit velocity (2 m/ s). Furthermore, maximum effectiveness of 0.489 is also obtained for GO nanofluid when compared with water and the refrigerant. On the other hand, the refrigerant has the maximum log mean temperature difference from all fluids with a value of 224.4 followed by water and GO.

PSIV-15 Examining the relationship between breed type and anabolic implant protocols in performance in the feedlot, health, and temperament of beef steers

The purpose of this research was to compare anabolic implant protocols in feedlot steers of two different breed types. Sixty steers were stratified by weight and breed in a 2 x 3 factorial design examining two different breeds: Angus (AN; n = 38) or Santa Gertrudis influenced (SG; n = 22), and three implant strategies: no implant (CON; n = 20), a moderate implant protocol (d0 implant: Revalor-G, d56 implant: Revalor-IS, d112 implant: Revalor-S; MOD; n = 20), or a vigorous implant protocol (d0 implant: Revalor-IS, d56 implant: Revalor-S, d112 implant: Revalor-200; VIG; n = 20). Steers were randomly placed into pens equipped with GrowSafe® bunks and fed the same ration. Weight, chute score (CS), exit velocity, blood, temperature, hip height and 12th rib fat thickness were collected approximately every 28d over a 112d period. Over the 112 d, SG steers tended (P = 0.10) to gain more hip height than AN steers. Anabolic implant protocol influenced total gain with both VIG and MOD steers gaining more (P &lt; 0.01) than CON. On d 0, SG steers had a higher (P &lt; 0.01) CS compared to AN steers, with this being maintained through the course of the trial. There was also as a tendency for there to be a breed*treatment effect (P = 0.06) on d112, with SG-MOD having a higher (P = 0.04) CS than AN-VIG, and a tendency (P = 0.08) for SG-VIG to have a higher CS than AN-VIG. Moderate and VIG implant protocols may be a useful tool to increase performance in feedlot steers. However, this research did find that SG influenced steers may have a more excitable temperament, but implant protocol did not influence (P &gt; 0.05) temperament.

PSXIII-20 Using 1H NMR Spectroscopy reveals metabolite markers associated to temperament and carcass quality in feedlot cattle

The objective of this study was to identify small molecule metabolites in a serum sample taken at entry into the feedlot that can predict performance, and animal health. One-hundred and thirty-one Angus x Simmental steers from a single ranch were sampled at a commercial feedlot in Chappell, NE. Blood samples for metabolite analysis, chute score, exit velocity, and blood lactate concentration for temperament classification were collected in addition to feedlot performance data and carcass quality measurements. The GLM and LSM procedures of SAS (SAS 9.4, 2014) were used to evaluate differences between temperament classifications. Steers were divided into three exit velocity classifications one standard deviation from the mean were classified as fast and exit velocities lower than one standard deviation from the mean were slow. Forty metabolites were quantified using 1H NMR Spectroscopy from serum. Metaboloanalyst was used to analyze serum metabolites and phenotypic values using one way- ANOVA, PCA, PLS-DA, and a permutation test to cross validate. Data were normalized and scaled. No metabolites were predictive of any of the animal health metrics collected. Five metabolites were different in exit velocity class at (P &lt; 0.01; Methanol, Isopropanol, Lactate, Isobutyrate, and Pyruvate). Similarly, seven metabolites were different in chute score classes at (P &lt; 0.01) (Methanol, Isobutyrate, Creatinine, Dimethly Sulfone, Hippurate, Isopropanol, and Succinate). Furthermore, several metabolites in serum at entry in the feedlot were related to carcass quality metrics; Back Fat (Urea and 2-Hydroxyisobutyrate at (P &lt; 0.01), a trend for prediction of quality grade at (P = 0.068), carcass value (P = 0.085). The relationship between serum metabolites identified on entry into the feedlot, feedlot performance traits, and eventual carcass quality warrants further research to elucidate the roles these metabolites play during the feedlot period and in predicting carcass merit.

Shape Prediction of the Sheet in Continuous Roll Forming Based on the Analysis of Exit Velocity

Continuous roll forming (CRF) is a new technology that combines continuous forming and multi-point forming to produce three-dimensional (3D) curved surfaces. Compared with other methods, the equipment of CRF is very simple, including only a pair of bendable work rolls and the corresponding shape adjustment and support assembly. By controlling the bending shapes of the upper and lower rolls and the size of the roll gap during forming, double curvature surfaces with different shapes can be produced. In this paper, a simplified expression of the exit velocity of the sheet is provided, and the formulas for the calculation of the longitudinal curvature radius are further derived. The reason for the discrepancy between the actual and predicted values of the longitudinal radius is deeply discussed from the perspective of the distribution of the exit velocity. By using the response surface methodology, the effects of the maximum compression ratio, the sheet width, the sheet thickness, and the transverse curvature radius on the longitudinal curvature radius are analyzed. Meanwhile, the correction coefficients of the predicted formulas for the positive and negative Gaussian curvature surfaces are obtained as 1.138 and 0.905, respectively. The validity and practicability of the modified formulas are verified by numerical simulations and forming experiments.

On Choosing the Optimal Impeller Exit Velocity Triangles in Preliminary Design

Impeller discharge flow plays an important role in centrifugal compressor performance and operability for two reasons. First, it determines the work factor and relative diffusion for the impeller. Second, it sets the flow into the downstream stationary diffusion system. The choice made in the preliminary design phase for the impeller exit velocity triangle is crucial for a successful design. The state-of-the-art design approach for determining the impeller exit velocity triangle in the preliminary design phase relies on several empirical guidelines, i.e. maximum work factor and diffusion ratio for an impeller, the optimal range of absolute flow angle, etc. However, as modern compressors continue pushing toward higher efficiency and higher work factor, this design approach falls short in providing exact guidance for choosing an optimal impeller exit velocity triangles due to its empirical nature as well as the competing mechanism of the two trends. In light of this challenge, this paper introduces a reduced-dimension, deterministic approach for the design of the impeller exit velocity triangle. The method gauges the design of the impeller exit velocity triangle from a different design philosophy using a relative diffusion effectiveness parameter and is validated using 6 impeller designs, representative of applications in both turbochargers and aero engines. Furthermore, with the deterministic method in place, optimal impeller exit velocity triangles are explored over a broad design space, and a one-to-one mapping from a selection of impeller total-to-total pressure ratios and backsweep angles to a unique optimal impeller exit velocity triangle is provided. This new approach is demonstrated, and discussions regarding the influences of impeller total-to-total pressure ratio, isentropic efficiency, and backsweep angle on the optimal impeller exit velocity triangle are presented.

Low-Energy Fragmentation Dynamics at Copahue Volcano (Argentina) as Revealed by an Infrasonic Array and Ash Characteristics

Ash-rich eruptions represent a serious risk to the population living nearby as well as at thousands of kilometers from a volcano. Volcanic ash is the result of extensive magma fragmentation during an eruption, and it depends upon a combination of magma properties such as rheology, vesicularity and permeability, gas overpressure and the possible involvement of external fluids during magma ascent. The explosive process generates infrasonic waves which are directly linked to the outflow of the gas-particle mixture in the atmosphere. The higher the overpressure in the magma, the higher should be the exit velocity of the ejected material and the acoustic pressure related to this process. During violent eruptions, fragmentation becomes more efficient and is responsible for the extensive production of ash which is dispersed in the atmosphere. We show that the phase of intense ash emission that occurred during March 2016 at Copahue volcano (Argentina) generated a very low (0.1 Pa) infrasonic amplitude at 13 km, raising a number of questions concerning the links among acoustic pressure, gas overpressure and efficiency of magma fragmentation. Infrasound and direct observations of the eruptive plume indicate that the large quantity of ash erupted at Copahue was ejected with a low exit velocity. Thus, it was associated with eruptive dynamics driven by a low magma overpressure. This is more evident when infrasonic activity at Copahue is compared to the moderate explosive activity of Villarrica (Chile), recorded by the same array, at a distance of 193 km. Our data suggest a process of rigid fragmentation under a low magma overpressure which was nearly completely dissipated during the passage of the erupting mixture through the granular, ash-bearing crater infilling. We conclude that ash released into the atmosphere during low-energy fragmentation dynamics can be difficult to monitor, with direct consequences for the assessment of the related hazard and management of eruptive crises.

Accurate Simulation of the Four Modes of Post-Die Extrudate Shape Distortion

A combined flow, thermal and structural analysis is employed to simulate post-die extrudate distortion in different profile dies. All four factors which can cause extrudate distortion, namely, nonuniform exit velocity distribution, extrudate shrinkage, extrudate draw down, and deformed shape of the calibrator or sizer profile, are simulated. To analyze the effect of exit velocity variation on extrudate distortion, the parameterized geometry of a simple profile die is optimized using an extrusion die optimization software. The simulation results presented for a bi-layer profile die successfully demonstrate how gradually changing profile shape in successive calibrators/sizers can be used to simplify the die design for extrusion of complex profiles. The predicted extrudate shape and layer structure for the bi-layer die are found to accurately match with those in the extruded product.

Effect of a 12-Week Off-Season Strength Training Program on Athletic Performance in Adolescent Baseball Players

Performing a 12-week strength training program increased running speed but not bat exit velocity or post-program hitting performance statistics. Baseball-specific strength training programs are safe and effective interventions that can improve athleticism in adolescents

385 Awardee Talk: Impacts of temperament on productive and reproductive responses of Bos taurus and B. indicus females

Temperament is defined as the fear-related behavioral responses of cattle when exposed to human handling. Our group evaluates cattle temperament using: 1) chute score: 1 to 5 scale that increases according to excitable behavior during chute restraining, 2) exit velocity: speed of an animal exiting the squeeze chute, 3) exit score: dividing cattle according to exit velocity into quintiles using a 1 to 5 scale (1 = slowest quintile; 5 = fastest quintile), and 4) temperament score: average of chute and exit scores. Subsequently, cattle are assigned a temperament type; adequate temperament (ADQ; temperament score ≤ 3) or excitable temperament (EXC; temperament score &gt; 3). Our group associated these evaluation criteria with reproductive responses of Bos taurus and B. indicus-influenced females. Cattle classified as EXC had greater (P ≤ 0.04) plasma cortisol vs. ADQ during handling, independent of breed type or parity. Both B. taurus and B. indicus cows classified as EXC had reduced (P ≤ 0.09) annual pregnancy rates vs. ADQ cohorts, resulting in decreased calving rate, weaning rate, and kg of calf weaned/cow exposed to breeding. Bos indicus heifers classified as EXC as yearlings had less (P &lt; 0.01) growth rate and delayed puberty attainment by 15 months of age compared with ADQ heifers. Bos taurus heifers that reached puberty by 12 months of age had less (P ≤ 0.05) temperament score and plasma cortisol concentrations at weaning compared with heifers that did not reach puberty. Acclimating B. indicus-influenced and B. taurus heifers to human handling after weaning improved (P ≤ 0.02) temperament and hastened puberty attainment. Hence, temperament impacts productive and reproductive responses of beef females independent of breed type and parity. Strategies to improve herd temperament are imperative for optimal production efficiency of cow-calf operations based on B. taurus and B. indicus-influenced cattle.