In this paper, two kinds of vibrations are considered for a composite Timoshenko rotor: longitudinal-torsional vibration and two plane transverse one. The kinetic and potential energies and virtual work due to the gyroscopic effects are calculated and the set of six governing equations and boundary conditions are derived using Hamilton principle. Differential quadrature method (DQM) is used as ...

The tests were carried out with the spark timing adjusted to the maximum brake torquetiming in various equivalence ratios and engine speeds for gasoline and natural gas operations. In thiswork, the lower heating value of gasoline is about 13.6% higher than that of natural gas. Based on theexperimental results, the natural gas operation causes an increase of about 6.2% brake special fuelconsumpt...

We established a mathematical model based on the sense of biological survey in field agriculture and introduced various control methods how to prevent crops from destructive pests. Basically, there are two main stages life cycle natural enemies like insects: mature immature. Here, we construct food chain plant pest enemy. In enemies, construction. Also, consider three classes diseases populatio...