Study on key grouting blocking parameters of gas drainage boreholes in soft coal seams.

The construction of gas extraction boreholes in soft coal seams is prone to collapse and deformation, and grouting reinforcement is one of the main methods to solve the problem of efficient sealing. However, the reasonable selection of key grouting parameters still needs further research. In response to the problem of selecting grouting sealing parameters for gas drainage drilling in soft coal seams, based on the "concentric ring" reinforcement sealing technology obtained in previous research, the key parameters and sealing technology of the "concentric ring" reinforcement were studied through theoretical calculation and numerical simulation experiments.

Jones pupil decomposition and its lithographic imaging impacts.

The Jones pupil is a full description of imaging properties of projection lenses in optical lithography. The decomposition of the Jones pupil into components with clear physical meanings was studied previously; however, the decomposition method has not been studied systematically. To generalize the existing decomposition method, this work is aimed at finding all the decomposition methods and analyzing the lithographic imaging impacts.

Inverse axial mounting stiffness design for lithographic projection lenses.

In order to balance axial mounting stiffness of lithographic projection lenses and the image quality under dynamic working conditions, an easy inverse axial mounting stiffness design method is developed in this article. Imaging quality deterioration at the wafer under different axial vibration levels is analyzed. The desired image quality can be determined according to practical requirements, and axial vibrational tolerance of each lens is solved with the damped least-squares method.

Automatic clocking optimization for compensating two-dimensional tolerances.

Clocking of lens elements is frequently used as an effective method of compensating for two-dimensional tolerances such as material inhomogeneity and surface figure errors. Typically, the lens designer has to determine the optimum angles of rotation by manually modeling lens element clocking in the commercial optical design software because the nature of errors resolved by lens clocking does not lead to good convergences for clocking optimization. In this paper, a method of automatic clocking optimization is developed.