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Abstract

With the evolution of better highway services and larger traffic volume, the traditional maintenance management indicators can no longer satisfy the demands of highway traffic safety. In order to ensure timely, fast, safe, and reliable highway maintenance and repair, this paper proposes a road traffic safety maintenance evaluation method. The fuzzy maintenance evaluation method based on the gray correlation degree is used to construct the safety maintenance evaluation model. The damaged characteristics of the high-grade highway components are analysed. The parameters of the evaluation model are established using the analytic hierarchy process, and the accuracy of the model is verified through experiments. The results show that the safety service level can intuitively measure the maintenance and repair status of various transportation facilities. When the safety level is 1 (above 87 points) or 2 (above 85 points), the road maintenance and repair are in good condition and the road users have a high level of satisfaction on safety; when the safety level is 3 or 4 (80 points or less), it reflects that there are weak links in the road components, and targeted maintenance repairs are required. The results provide references for highway safety maintenance decision-making and improvement of highway traffic safety services to some extent.

Abstract

The simulation of bone remodelling is highly complex due to the high nonlinear coupled relations between the damage and repair behaviours. In this paper, a new bone remodelling model based on the fatigue damage mechanism is proposed. Then the repair process of the human femur is simulated based on the finite element method. The results show that the new damage model can well simulate the bone damage evolution caused by overloadings. This indicates that the new mathematical model suggested in this paper can simulate the effect of external load on the cortical bone density and the related mechanical properties of the cortical bone.

Abstract

This paper studies the robot arm sorting position control based on robot operation system (ROS), which works depending on the characteristics of the robot arm sorting operation using the top method, to automate the sorting operation and improve the work efficiency of workpiece sorting. Through the ROS MoveIt! module, the sorting pose and movement path of the robotic arm are planned, the inverse kinematics of the sorting robotic arm is solved, and the movement pose characteristics of the sorting robotic arm are analysed. The robot arm model was created using Solidworks software, and the URDF model file of the robot arm was exported through the sw2urdf plugin conversion tool, and the parameters were configured. Based on ROS for 6-degree-of-freedom (DOF) robot motion simulation, random extended tree (RRT) algorithm from open motion planning library (OMPL) is selected. The robot motion planning analysis and sorting manipulator drive UR5 manipulator. The results show that the sorting pose and motion trajectory of the robot arm are determined by controlling the sorting pose of the sorting robot arm, and the maximum radius value of the tool centre point (TCP) rotation of the robot arm and the position of the workpiece are obtained. This method can improve the success rate of industrial sorting robots in grabbing objects. This analysis is of great significance to the research of robots’ autonomous object grabbing.

Abstract

At present, the economic benefits of double inlet and double outlet ball mills, which are commonly used in coal-fired power plants, need to be improved. Based on this, this paper explores the factors influencing the output of double inlet and double outlet ball mill by establishing the output system of double inlet and double outlet ball mill. By analyzing the influence factors of the output of double inlet and double outlet ball mill, and combining with system dynamics, the dynamic model of double inlet and double outlet ball mill output system is established, and SPSS is used to fit the model data with the real data. The fitting degree is above 0.8, and the authenticity is high. The simulation results show that the impact energy of barrel grinding, the grinding powder fineness, and the pressure ratio in the ball mill affect the output of double inlet and double outlet ball mill according to certain relations. Finally, the research in this paper provides theoretical and technical support for improving the economic benefits of double inlet and double outlet ball mills.

Abstract

Based on investigation of existing folding wheelchairs’ usage, this paper analyzed wheelchair size and material in human-machine system model. The importance of new environmentally friendly materials’ application on wheelchair component producing in recent years was also explained. On the basis of strength and stiffness theory and calculation, applied materials were determined and rod mechanical calculation were carried out. The calculated results will have certain theoretical significance for wheelchair research and design.

Abstract

In this paper, the Incomplete Global GMERR algorithm and the Global GMERR algorithm are used to solve the Sylvester equation. The numerical experiment is given to compare the CPU run time and the number of iterations of the two methods.

Abstract

In the classical Lotka-Volterra population models, the interacting species affect each other's growth rate. We propose an alternative model, in which the species affect each other through the limitation coefficients, rather then through the growth rates. This appears to be more realistic: the presence of foxes is not likely to diminish the fertility of rabbits, but will contribute to limiting rabbit's population. Both the cases of predation and of competition are considered, as well as competition in case of periodic coefficients. Our model becomes linear when one switches to the reciprocals of the variables. In another direction we use a similar idea to derive a multiplicity result for a class of periodic equations.

Abstract

This paper studies a land primary development project in Pinggu District as an example for analysis since the complete survey data and adequate data analysis are not available on the assessment of social impact from primary development projects of land. In this paper, we carry out regression analysis based on statistical analysis of survey data, explore the attitudes of stakeholders towards development projects, and find out the main factors and risk problems. Finally, the required policy changes based on the analysis are recommended and put forward to provide reference for impact assessment of social stability.

Abstract

The concept of inequalities in time scales has attracted the attention of mathematicians for a quarter century. And these studies have inspired the solution of many problems in the branches of physics, biology, mechanics and economics etc. In this article, new principles of non-linear integral inequalities are presented in time scales via diamond-α dynamic integral and the nabla integral.