An expression of an excavator fittign out loading buckets of a truch was derived, and an ac-tual open-pit was verified with orthogonal experiment optimization.

The influence of technical parameters of temperature, pressure and time on vacuum diffusion welding of horizontally projected jet bits on the shear strength of the welding seam was studied by orthogonal optimization test.

The influences of the technological parameters of vacuum diffusion bonding of logging ceramic probe(Al2O3 ceramic to 45 steel) such as temperature,pressure and time on the shear strength of the bonging seam were studied by the orthogonal optimization test.

Using optimal design of orthogonal test, and analyzing the data from relative statistics analysis method, the optimal parameters array can be gotten in the circumstance of reducing testing frequency, so that testing frequency is reduced,both resources of human and material get saved, and total costs get lowered, which especially fits for the defining of actual processing parameters.

The inspected liquid cases with different full rate were chosen by orthogonal optimization test method.

The optimization of concrete mix proportion is achieved through an optimization experiment on the raw materials of face-sheet concrete, variety-selection of applied dose, concrete mix proportion at Gaotang Reservoir.