MOMENTS IMPARTED TO A BOWLING BALL: INTRODUCING CONTINUOUS 3D MOMENT VECTOR DIAGRAMS FOR PERFORMANCE ANALYSIS

Bowling, a typical skill sport, requires exact motion timing and control of finger forces and moments. The latter, the moments applied by the three fingers to the ball, were measured with an instrumented bowling ball in bowlers of different performance levels and in different shots. The results showed, that, in better bowlers, the magnitude of the moment vectors are higher than in beginners and average bowlers. Moment vectors and their 3D vector diagrams are an important tool for performance diagnostics and allow a clear differentiation between straight, hook, and spin shots

PERFORMANCE DIAGNOSTICS WITH INSTRUMENTED RACING WHEELCHAIRS: COMPARISON OF ATHLETES OF CLASS T52 AND T53

The purpose of this study was to develop a cheap and flexible instrumentation system for on-track monitoring of velocity and associated parameters. Two wheelchairs of two top athletes (class T52 and 53) were equipped with a ferrite motor connected to the rear wheels and the back EMF (electromotive force) was converted to velocity after filtering and calibrating. Drag and rolling resistance were determined from the decreasing velocity when rolling freely and from a differential equation. In two 100 m races per athlete, the velocity, peak push acceleration, push frequency, inertial, drag and friction forces, peak push power and energy were calculated. Athlete 1 (T53) reached twice the maximum velocity and six times the average peak push power of Athlete 2, and produced 2.7 times as much energy over 100m. The system developed is useful for optimising race training

Integrated assessment of crop management portfolios in adapting to climate change in the Marchfeld region

Portfolio optimization is an adequate tool to find optimal crop management options in adapting to climate change. The risk farmers have to face can be caused by different sources. In our study, we focus on the risk arising from unknown weather conditions. Therefore, we developed stochastic climate change scenarios for the Marchfeld region. Two portfolio models have been applied in the time periods 2008-2020, 2021-2030 and 2031-2040: a traditional non-linear mean-variance (E-V) model and a model using the Conditional Value at Risk (CVaR) as risk metric. Investigated crops are corn, winter wheat, sunflower and spring barley with different crop management alternatives. Minimum tillage appears in all portfolios. We found a decreasing share of winter wheat that gets partially substituted by sunflower over the time periods. When including environmental constraints (soil organic carbon content, nitrate leaching) the reverse effect on the resulting portfolio shares is observed with corn being included. The E-V model reveals more diversification with respect to the crops, whereas the CVaR model shows more diversification with respect to crop management options

Optimal irrigation management strategies under weather uncertainty and risk

Climate change will affect agricultural production through changes in water supply, such that optimal irrigation management strategies gain importance. For the Marchfeld region, we firstly analyze with a stochastic dynamic programming approach the probability of investing into either a water-saving drip or a sprinkler irrigation system until 2040. Secondly, we develop optimal irrigation management portfolios for different degrees of risk aversion using climate data from a statistical model and the simulations for specific crops of the biophysical process model EPIC (Environmental Policy Integrated Climate). Investment in drip irrigation systems is not profitable. Sprinkler irrigation has a positive probability of being adopted for the production of sugar beets and carrots and therefore mostly shows a 100% share in the portfolio optimization

Relationship of Students Who Participated in the Oklahoma State FFA Interscholastic Contests During 1967-69 and their Choice Field of Study at Trade, Technical, Junior College, College or University Level

Agricultural Educatio