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This paper presents an optimization-based method for predicting a human dynamic lifting task. The three-dimensional digital human skeletal model has 55 degrees of freedom. Lifting motion is generated by minimizing an objective function (human performance measure) subjected to basic physical and kinematical constraints. Four objective functions are investigated in the formulation: the dynamic effort, the balance criterion, the maximum shear force at spine joint and the maximum pressure force at spine joint. The simulation results show that various human performance measures predict different lifting strategies: the balance and shear force performance measures predict back-lifting motion and the dynamic effort and pressure force performance measures generate squat-lifting motion. In addition, the effects of box locations on the lifting strategies are also studied. All kinematics and kinetic data are successfully predicted for the lifting motion by using the predictive dynamics algorithm and the optimal solution was obtained in about one minute.

We investigate producers’ choice between geographical indications (GI) and brand advertising (BA) as pure marketing strategies to convey information to consumers. Producers also decide whether or not to select an effort level for improving the quality of their products. We identify conditions under which GI and BA emerge with and without quality effort, depending on the relative costs and effectiveness of marketing strategies and quality improvement. Beyond the conventional equilibrium cases of GI-no-quality-effort and BA-with-quality-effort, we identify several other equilibrium strategies. Under plausible parameter characterization, and in spite of the free-riding problem of collective reputation, producers choose GI and quality improvement efforts at equilibrium. This occurs when the cost of marketing is high, the relative cost of quality effort is low relative to the former, and when the effectiveness of marketing promotions is low. BA without quality improvement also emerges as an equilibrium strategy for the opposite cost structure (low cost of promotion, high cost of effort relative to promotion, and higher effectiveness of promotion). Finally, the joint selection of both instruments BA and GI is examined. We motivate and illustrate our analysis with the European and New-World wine industries.