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In planetary science, it is an important basic work to recognize and classify the features of topography and geomorphology from the massive data of planetary remote sensing. Therefore, this article proposes a lightweight model based on VGG-16, which can selectively extract some features of remote sensing images, remove redundant information, and recognize and classify remote sensing images. This model not only ensures the accuracy, but also reduces the parameters of the model. According to our experimental results, our model has a great improvement in remote sensing image classification, from the original accuracy of 85%–98% now. At the same time, the model has a great improvement in convergence speed and classification performance. By inputting the remote sensing image data of ultra-low pixels (64 * 64) into our model, we prove that our model still has a high accuracy rate of 95% for the remote sensing image with ultra-low pixels and less feature points. Therefore, the model has a good application prospect in remote sensing image fine classification, very low pixel, and less image classification.

In order to meet the needs of data processing, information communication, etc., many modern electronic devices are equipped with PCBs inside, which has an impact on the shielding effectiveness of the metal cavity with holes. Based on the extended transmission line method, the PCB is equivalent to a dielectric slab of the same thickness and the calculation formula of the shielding effectiveness is deduced. The shielding effectiveness of the cavity is compared in the presence or absence of the PCB. The influence on shielding effectiveness of the thickness, mounting position, permittivity, conductivity and other factors of the PCB are analyzed. The effectiveness of the established model is verified by comparing the simulation results with the electromagnetic simulation software CST. The research results can provide reference for electromagnetic pulse effect analysis and electromagnetic safety protection design of electronic devices.

An approach is proposed to analyze the conducted coupling effect of the electromagnetic pulse based on integral equation equivalent circuit and electromagnetic topology. Based on the integral equation equivalent circuit method, an equivalent source model of the external electromagnetic interference is established. The output of the equivalent source model is taken as the input of the internal circuit. The electromagnetic pulse conduction coupling effect is calculated based on the electromagnetic topology analysis and Baum-Liu-Tesche(BLT) equation. The method can be used for the analysis of the electromagnetic pulse effect of electronic devices containing complex transmission line networks and integrated circuit plug-ins, and is closer to the reality of electronic devices. The influence of the cable amount on the conducted coupling effect is analyzed. Experimental results are compared with the electromagnetic simulation software CST to verify the effectiveness of the proposed method.

In this paper, we studied the Position&Force servo control of the voice coil motor commonly used in semiconductor packaging equipment and analyzed its Position&Force servo control switching strategy. System identification is the basis for high-speed, high-precision motion control. We use the frequency domain identification method to identify the voice coil motor system. The frequency domain identification method uses sine sweep frequency and PRBS method to compare and verify. Feedback and feedforward servo control structures are used to ensure quick response and precise control of voice coil motors while ensuring system stability. In the feedforward control, we use an iterative learning control method. In semiconductor packaging equipment, the movement of the voice coil motor has always been a similar process cycle. Iterative learning control (ILC) has prominent control effects in situations where control objectives and external disturbances are periodic or repetitive. The iterative learning control algorithm is applied to the feedforward plus feedback servo control structure of the voice coil motor. From the actual effect point of view, the trajectory tracking ability of the voice coil motor during high-speed motion is significantly increased. The voice coil motor servo control algorithm described above is written on the DSP and verified on the motion control card. The experimental results show that the above servo control algorithm realizes the high speed and high precision motion control of the voice coil motor.

In this paper, a 4-DOF (Degrees of Freedom) direct-drive SCARA (Selective Compliant Assembly Robot Arm) robot is designed for wafer&ceramic-substrate handing purpose. In order to improve the flexibility of the whole wafer&ceramic-substrate handling system, we abandon the traditional aligner which can only achieve accurate positioning of the wafer and for ceramic-substrate is powerless, but introduce the visual servoing control strategy to excellent achieve the purpose of rapid and accurate aligning of the wafer&ceramic-substrate. In view of the structural characteristics of SCARA robot, we adopted the XY/Z-Partitioned IBVS scheme, which realized the control decoupling of x-, y-axis and z-axis. The reliability of visual servoing control strategy is verified by simulation and the physical prototype of the SCARA robot. Performance meets with the requirements in the wafer&ceramic-substrate handling process.

An experiment was conducted by fertilizer packet burying method to determine the nitrogen release of SCU, PSCU and PCU in the soil during corn and wheat planting period. Results showed that Packet burying method can be used to measure the nitrogen release characteristics of coated controlled release urea in soil. This test method can simulate the nutrient release situation of controlled release fertilizer applied in soil. It plays an important role in fitting fertilizer demand with fertilizer supply during plant growth period as well as improving the precision of controlled release fertilizer using.

This paper reports the application of auditory perception in the sparse representation and compressed sensing for speech signal. In order to obtain a more sparse representation, an experiment of sparse coefficients' selection under masking threshold method was done comparing with the energy threshold method, results indicate that the masking threshold method is more effective. In order to verify the impact of the method to compressed sensing for speech signal, the testing speeches were compressed under compressed sensing framework by masking threshold method and energy threshold method, through some subjective and objective indicators, such as compression ratio, signal noise ratio and mean opinion score, results imply that the masking threshold method can be applied effectively in compressed sensing, and can lead an increasing of compression ratio while the hearing quality of reconstructed signal is not decreased.

Violation problem in coal transportation has puzzled coal enterprises for a long time. Taking use of the evolutionary game theory, the paper builds the game model of coal transportation analyzing the dynamic evolution process of both sides' strategy. The results show that the transportation game is a dynamic process and the coal enterprises' can take measures to promote the transportation game evolving to the ideal running state (no supervision, no violation) and the measures are as follow: reducing the regulatory costs by improving the regulatory efficiency, improving of the transportation assessment mechanism by establishing the performance bonus, increasing the punishment strength and deepening the understanding of the importance of the coal transportation.