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The Coronavirus Disease 2019 (COVID-19) has spread globally and caused serious damage. Chest X-ray images are widely used for COVID-19 diagnosis and the Artificial Intelligence method can increase efficiency and accuracy. In the Challenge of Chest XR COVID-19 detection in Ethics and Explainability for Responsible Data Science (EE-RDS) conference 2021, we proposed a method that combined Swin Transformer and Transformer in Transformer to classify chest X-ray images as three classes: COVID-19, Pneumonia, and Normal (healthy) and achieved 0.9475 accuracies on the test set.

How to improve the electrical energy utilization of traditional mechanical and electrical equipment is a problem that deserves to be discussed, especially now when energy usage and sustainability is becoming more and more important. From the view point of energy, the closing process of AC contactor is an energy exchange process with the input electric energy changing into kinetic energy, thermal energy and magnetic field energy. If the input energy is more than the expended energy, then the excess energy will be exhibited as bounce of contacts and cores. Therefore, controlling the input energy and the distribution of each kind of energy in the closing process will result in significant reduction in contact bounce. In addition, the electrical endurance and the overall performance will be improved. Selecting one kind of AC contactor which applied in-air condition as prototype in this paper. The energy distribution of contactor is analyzed based on the 3D dynamic simulation system. Then, the energy calculation model is developed and verified through the experiment.

AC contactor is a kind of low-voltage electrical apparatus which applied widely. The bounce of the contact in the closing process is one of the important factors which will affect the system performance and its electrical endurance. The closing process of AC contactor is a nonlinear and complex dynamic process. If the input energy is more than the expending energy which caused by coil and the others, and then the excess energy will be consumed by bounce of contacts and cores. Therefore, more and more research has been done on the contact bounce in the closing process. With the continuous development of intelligent control technology, the bounce of cores and contacts can be reduced or even eliminated by controlling the AC contactor's dynamic process through modern control technology based on a reasonable structural design. On the basis of energy distribution of AC contactor in the closing process, a control program is designed for controlling the energy in each stage for suppressing the bounce of contacts and cores. As a result, the energy-efficient operation of AC contactor is realized. The controller is verified through the experiment.

The properties of n-Ge epilayer deposited on Si substrate with in-situ doping technology in a cold-wall ultrahigh vacuum chemical vapor deposition (UHVCVD) system are investigated. The growth temperature of ~500 °C is optimal for the n-Ge growth in our equipment with a phosphorus concentration of ~1018 cm−3. In the n-Ge epilayer, the depth profile of phosphorus concentration is box-shaped and the tensile strain of 0.12% confirmed by x-ray diffraction measurement is introduced which results in the red shift of the photoluminescence. The enhancements of photoluminescence intensity with the increase of the doping concentration are observed, which is consistent with the modeling of the spontaneous emission spectrum for direct transition of Ge. The results are of significance for guiding the growth of n-Ge epilayer with in-situ doping technology.

Solenoid Valve is a kind of typical low voltage electrical appliance with special working characteristic. Take FDF (FDF is a series of model of solenoid valve Sanhua company produces) series solenoid valve for example which applied widely in refrigerating system. Its temperature rise, vibration noise and so on are key points affecting the product quality. At present, the research on solenoid valve mostly specific to the field in system response time and structure design and it lacks the analysis on the overall performance indexes and optimal design. Therefore, the development of miniaturization, less consumption of the energy and the artificial intelligence of solenoid valve will be restrained. The simulation analyzing system for dynamic characteristic and temperature calculation in working state, dynamic characteristic analysis and integrated optimized design is built and it forms unique database of electrical appliance characteristic analysis and simulation design. It focuses on optimization design module in this paper. The changing regularity of the temperature rise of the electromagnetic mechanism is researched and concluded based on the 3D simulation in electromagnetic and temperature field. And the regular is brought into the optimization design of electromagnetic mechanism. Ant colony optimization is used in the optimal design for the overall performance index, and the dynamic process of the closing state and closed in long term working state are also considered at the same time. The design result is quite satisfied.