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High altitude parabolic is difficult to identify because of its small size, fast speed and changeable state, which makes it difficult for subsequent forensics and accountability. This paper proposes a high-altitude parabolic detection and tracking method GPK-YOLOv5s, which integrates Content-Aware Reassembly of Features (CARAFE) and self-attention to realize parabolic detection and tracking. For the detection network, the backbone integrates C3Ghost module to extract effective features and simplify the network. C3Transformer module is embedded in the feature extraction and fusion layer to pay attention to the global context information. The feature fusion layer uses CARAFE module for up sampling to perceive effective features, and integrates shallow features and deep features to form a new large-scale detection layer (Output4) to further obtain smaller receptive fields. Improved multi-scale detection heads are embedded with CBAM to enhance the expression ability of targets. To overcome the frame loss of real-time detection, improved multiscale detection heads are externally connected with Kalman filter to track targets. This experiment verifies that the detection Precision, Recall and F1 value of GPK-YOLOv5s reached 99.0%, 98.6% and 98.8% respectively, which are 2.8%, 4.1% and 3.5% higher than YOLOv5s respectively. And GPK-YOLOv5s is lighter, and the calculation consumption is reduced by 0.4 GFLOPs.

"Signals and Systems" is the core professional course of electronic information majors. Aiming at its characteristics of strong theory, abstract content, and high memory requirements, a virtual teaching platform based on LabVIEW is designed to strengthen students' understanding of this course It is of great significance to reduce the difficulty of students' learning, improve students' learning efficiency, and stimulate students' interest in learning. At the same time, with the synchronous teaching of relevant course experiments, it can greatly reduce the difficulty of teachers' teaching and improve the quality of teaching.

Found in the routine quality inspection of highway bridge that many vertical fractures on the main beam (10mT beam) of the steel reinforced concrete arch bridge near the hydropower station. In order to grasp the bearing capacity of this bridge under working conditions with cracks, the static load and dynamic load test of box arch bridge are carried out. The Midas civil theory is calculated by using the special plate trailer - 300 as the calculation load, and the deflection and stress of the critical section are tested by the equivalent cloth load in the test vehicle. The pulsation test, obstacles and no obstacle driving test were carried out. Experimental results show that the bridge under the condition of the test loads is in safe condition, main bearing component of the strength and stiffness meet the design requirements, the crack width does not increase, in the process of loading bridge overall work performance is good.

Bridge structure plays a very important role in human traffic. The evaluation of bridge structure after a certain period of operation has always been the focus of the bridge. Based on the data collected from the health inspection system of a continuous rigid frame bridge on a highway in Yunnan, China, it is found that there is a certain linear relationship between the deformation and stress of the bridge structure. In view of a specific section of the structure, the stress value of this section can be derived according to its deformation value. The coefficient K can be calculated by comparing the estimated value to the actual measured value. According to the range of the K value, the structural state of the bridge can be evaluated to a certain extent.

In this paper, with the principle of least action with variables to solve the problems of forced vibration of the Rectangular plate with three clamped and the other free with concentrated load, and the stable solution can be worked out. We can compare the results with the literate; it also can be proved to be true. So the results by calculating not only it have important academic value, but also it can be directly referred in the actual work.