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Aiming at the problem that the lattice feature exceeds the view field of the scanning electron microscope (SEM) measuring system, a new lattice measuring method is proposed based on integral imaging technology. When the system works, the SEM measuring system is equivalent to an integral image acquisition system. Firstly, a lattice measuring method is researched based on integral imaging theory. Secondly, the system parameters are calibrated by the VLSI lattice standard. Finally, the value of the lattice standard to be tested is determined based on the calibration parameters and the lattice measuring algorithm. The experimental results show that, compared with the traditional electron microscope measurement method, the relative error of the measured value of the algorithm is maintained within 0.2%, with the same level of measurement accuracy, but it expands the field of view of the electron microscope measurement system, which is suitable for the measurement of samples under high magnification.

In order to improve the measurement accuracy of the step height measuring instrument, a semiconductor process was used to prepare the step height standard for calibrating the instrument. Aiming at the problem of deviation in the white light interferometer measuring step height standard, the cause of the measurement deviation was theoretically analyzed, combining the optical theory and the principle of instrument. In addition, referring to the semiconductor sputtering process, a method of sputtering metal layer on the surface of the step structure was proposed, and a set of universal step height standards with a nominal value of [Formula: see text] nm were developed for the step height measuring instrument. Finally, the step height standards with the sputtered metal layer were compared and measured, using the white light interferometer and nanometer measuring machine (NMM). The measurement error of the white light interferometer can be effectively controlled within 1%, which is beneficial to verify the measurement capability of the step height measuring instrument.

This paper introduces the failure law of the floating structures by an engineering examples of the up-floating accident. The reasons of the accident are insufficience of anti-floating anchor rod, short of the length of anchor rod and early termination of precipitation, according to the analysis about the design and the construction information. Through the new anti-floating anchor and new reinforced concrete slab, the whole anti-uplift and partial anti-uplift of underground parts of the floating structure are strengthened. The frame columns and beams with cracking damage caused by the up-floating accident are strengthened with enlarging section method and the enclosure steel method.

The module partition of NC spiral bevel gear machine tools is researched in detail in this paper. The module partition method we used is based on the function analysis. First we establish the black-box model of machine tools, and then further broke down into the function structure chart, and then machine tool is divided into modules based on the chart. Finally, an evaluation module of reasonable degree of module partition is proposed by introducing the concept of information entropy.