In order to find the change characteristics of wheat stem lodging under the rectangle wind load, wheat stem models were set up which include 5 inter-nodes, and then the process of wheat stem lodging were simulated by finite element software ANSYS/LS-DYNA. The simulation results show that the lodging is related to impulse of the rectangle wind load. The smaller the impulse is, the more difficultly the stem lodging happen. Along the entire stem axis, the maximum stress value occurs in the ovalization area, the stress values are smaller in the other area. The study results provide some references for the research on high yield cultivation and lodging resistance of wheat and plant stem processing.

Wheat lodging results in great losses of wheat production about 10%~30% every year. It is very important to study the lodging and to find new way to improve the quality of wheat stalks and its anti-lodging characteristics. The study about the changing of wheat stem mechanical properties with the elastic modulus and stem structure is carried on the basement of theoretical model, experimental improvement, and finite element method. Results show that the stem is more difficult to lodge if the ratio is bigger, which can be calculated through elastic modulus multiplying wall thickness and divided by diameter.

Primary factors determining surface figure of optics, including the velocity and pressure distributions, have been analyzed and improving methods provided accordingly for the pad continuous polishing (CP). With a septum on the exterior of the workpiece pre-pressing the pad, the inevitable depression on the edge of the workpiece incurred by the elastic response of the pad has been relieved obviously. By introducing the driving wheel system, the rotation speed of the septum & workpiece can be regulated and adjusted to that of the lap/pad, which produces a uniform velocity distribution on the polishing surface. Diamond conditioners with ring & disk patterns are employed to planarize the annular polyurethane pad and hence uniformise the pressure distribution on the workpiece/pad interface. Polishing experiments (Fused silica flat, 320 mm in diameter x 30 mm thick) conducted on the typical CP machine have demonstrated advantages of these methods.

Based on the mechanism of magnetorheological finishing(MRF), a material removal model was established. The dwell time function was solved by Jansson-Van Cittert algorithm to accomplish the kernel module design. Thus the control software of aspheric optics in MRF was designed. In order to verify accuracy of the processing control software, experiments were carried out on large aperture aspheric optics and the wavefront error of elements was achieved rapidly convergence. It is proved that the software could control the whole polishing process accurately.

The broken-explosive warhead for back deep underground target and airport runway hard target has a unique advantage. Through analyzing hard target characteristics of the concrete , process using ANSYS/LS-DYNA software to break-explosive warhead of a warhead forming process and penetration into concrete target is studied by numerical simulation. Experiments show: the simulation results are accurate. A warhead on concrete penetration and expanding role better, open a channel for level two warhead implement efficient damage. To counter this deep underground and airport target road of hard target penetration has a certain application prospect.