This paper investigates the damaged area of a reinforced concrete beam under rectangular explosive contact explosion, through full-scale beam tests and numerical simulation. The calculation equation of beam surface load distribution based on equivalent impulse is established, with a consideration of the effect of the length and height of rectangular explosive on the load distribution, and the calculation equation of beam damage area is further proposed. Through changing the mass of the rectangular TNT explosive (1~6 kg) and the shape of the 1 kg rectangular explosive, 5 cases of the test were carried out on a full-scale reinforced concrete beam. The damaged area of the beam is divided into three parts: blasting crater, damage span of the front face, and damage span of the bottom face. The RHT (Riedel–Hiermaier–Thoma) material model is used to simulate concrete for numerical simulation. Curve fitting was performed based on the numerical simulation results. With the prediction of the load distribution on the beam surface, the size of the surface crushing area and the span of the damaged area are calculated; the section resistance function of the beam is introduced to calculate the depth of the blasting crater; and the correlation curve between the damaged span of the front face, the depth of the blasting crater, and the mass of the block TNT is established. The local damage to the beam under the contact explosion load can be evaluated more accurately when the mass of the rectangular TNT is 1~6 kg.

This paper focuses on the effect of magnetron sputtering process parameters on the performance of thin metal film. Copper–tin alloy metal film was deposited on both sides of the PVDF film using direct current magnetron sputtering technology, and the effects of different working pressures, sputtering powers, sputtering times, and argon flow rates on the uniformity, deposition rate, and electrical conductivity of the metal film were studied separately. The main and minor factors affecting the conductivity of the metal film were determined by multiple linear regression, and the process parameters were optimized. The optimal process parameters include a working pressure of 0.065 Pa, a sputtering power of 70 W, a sputtering time of 20 min, and an argon flow of 20 SCCM. The samples with the best electrical conductivity were analyzed by scanning electron microscopy and energy spectrometry for microscopic morphology and elemental composition. The experimental results showed that the sputtering time and sputtering power have a greater effect on the metal film uniformity and that the working pressure and argon flow rate have a smaller effect on the metal film uniformity; when the working pressure is lower, the sputtering power is higher, the sputtering time is longer, the argon flow rate is higher, and the conductivity of the sputtered metal film is better. The deposition rate decreased with the increase in the working pressure and increased with the increase in the sputtering power and argon flow rate. The working pressure is the main factor affecting the conductivity of the metal film, and the sputtering power and sputtering time are secondary factors.

In view of the uncertainty of model parameters, the influence of external disturbances and sensor noise on the flight of coaxial rotor aircraft during autonomous flight, a robust backstepping sliding mode control algorithm for the position and attitude feedback control system is studied to solve the trajectory tracking problem of an aircraft in the case of unknown external interference. In this study, a non-linear dynamic model based on a disturbed coaxial rotor aircraft was established for an unknown flight. Then, a non-linear robust backstepping sliding mode controller was designed, which was divided into two sub-controllers: the attitude controller and the position controller of the coaxial rotor aircraft. In the controller, virtual control was introduced to construct the Lyapunov function to ensure the stability of each subsystem. The effectiveness of the proposed controller was verified through numerical simulation. Finally, the effectiveness of the backstepping sliding mode control algorithm was verified by flight experiments.

The performance of supercapacitors is directly influenced by the conductivity of polypyrrole, which serves as the electrode material. In order to balance considerations of cost-effectiveness and conductivity, this study employs magnetron sputtering to fabricate a copper–tin alloy layer as the conductive layer for polypyrrole. The deposition of a copper–tin alloy film through magnetron sputtering has a significant impact on the polymerization effect of pyrrole as well as being a crucial factor influencing the performance of supercapacitors. Various parameters, including working pressure, sputtering time, and sputtering power, affect the conductivity of the copper–tin alloy film. Furthermore, the degree of influence of each parameter on the conductivity of the copper–tin alloy film varies. This study utilizes an orthogonal experimental design to investigate the impact of various factors and levels on the conductivity and uniformity of a metal film. The objective is to optimize the process parameters for the creation of a copper–tin alloy film with desirable characteristics. Experimental results indicate that the working voltage, sputtering time, and sputtering power significantly influence the coefficient of variation, deposition rate, target current, and operating voltage of the film. Furthermore, FT-IR, XRD, and SEM tests are conducted on samples prepared using the identified optimal process parameters. In addition, we demonstrate various approaches to enhance the experiment’s reliability. The findings indicate that the most favorable process parameters for achieving optimal results are a working pressure of 0.065 Pa, a sputtering time of 20 min, and a sputtering power of 70 W. It was observed that the sputtering time significantly influences the uniformity of the copper–tin alloy film, whereas the sputtering power has a minimal impact on its uniformity. The deposition rate is primarily influenced by the working pressure, with the greatest effect observed. Conversely, the sputtering time has the least impact on the deposition rate. Similarly, the target current is predominantly affected by the sputtering power, exhibiting the greatest influence, while the sputtering time has the least effect. Furthermore, the working voltage is most significantly influenced by the working pressure, whereas the sputtering time has the least impact on the working voltage.

Many real-world scheduling problems can be modeled as Multi-mode Resource Constrained Project Scheduling Problems (MRCPSP). However, the MRCPSP is a strong NP-hard problem and very difficult to be solved. The purpose of this research is to investigate a more efficient alternative based on ant algorithm to solve MRCPSP. To enhance the generality along with efficiency of the algorithm, the rule pool is designed to manage numerous priority rules for MRCPSP. Each ant is provided with an independent thread and endowed with the learning ability to dynamically select the excellent priority rules. In addition, all the ants in the ant algorithm have the prejudgment ability to avoid infeasible routes based on the branch and bound method. The algorithm is tested on the well-known benchmark instances in PSPLIB. The computational results validate the effectiveness of the proposed algorithm.