Abstract:The performance of active suspension is considered to be better than that of passive suspension. A 2degree of freedom model of quarter car active suspension system was designed, which is subject to road disturbance. A robust control scheme was proposed for input with unknown nonlinear dead zone. The controller can eliminate the residual vibration caused by the inaccurate parameters. H∞ controller improves vehicle ride comfort and handling capabilities as well as system robustness. The simulation results show that the H∞ controller is robust to the uncertainty of system parameters. It can effectively reduce the harmful influence of the dead zone on the system, control unpredictable interference within the input range, and provide overall stability of the active suspension.

Abstract:By applying electromagnetic diffusion equation, skin effect in electrical steel sheets in the condition of alternating excitation is analyzed based on Maxwell electromagnetic field theory in this paper. Due to skin effect is more significant mainly at high frequency, non-dimensionalized treatment for the diffusion equation is produced and eddy current loss is calculated by considering and not considering skin effect, respectively. Meanwhile, broadband magnetic losses and separation of a kind of typical electrical steel are obtained by using a 3D magnetic properties testing system to bring to light the emergence of skin effect under rotational excitation. The simplification of magnetic constitutive equation is proposed and introduced into the diffusion equation, which is solved by employing finite elements coupled to Fredholm’s equation. An approximate expression for the rotational eddy current loss component with skin effect is eventually written.

Abstract:In order to study the influence of constraints, indenter size and other external factors on the radial compression mechanical properties of steel pipe, a cylindrical indenter was used to conduct radial compression tests on six groups of steel pipe specimens, and to compare and analyze structural deformation, bearing capacity and energy absorption characteristics.The test results show that the setting of v-shaped constraint has a significant impact on the plastic deformation mode of steel tube, which extends the contact stroke of concave buckling deformation of steel tube, and greatly improves the sealing effect of cavity on both sides of the contact point.The structural bearing capacity, the average crushing load and the total deformation energy are proportional to the Angle of the restraint body, the diameter of the indenter and the spacing of the V body, and inversely proportional to the loading rate.In the end, a new design scheme of internal blowout preventer is put forward to deal with the out-of-control blowout of oil well.

Abstract:Reliability analysis is a key technology to determine the reliability of hydraulic systems and components. Bayesian networks are a common method for reliability analysis of hydraulic systems. However, in practical engineering, the uncertainty and polymorphism of the hydraulic system degrade the performance of traditional Bayesian network reliability analysis. Based on this, this paper proposes an improved reliability analysis method for Bayesian network hydraulic system based on evidence theory. Firstly, the likelihood probability and trust probability of the evidence theory are used to describe the failure probability interval of the root node, which effectively processes the uncertain information of the hydraulic system and accurately extracts the failure probability of the root node. Then, based on Bayesian inference, the fault probability of the leaf node and the sensitivity interval of the root node are obtained, which effectively describes the polymorphism of the hydraulic system. The example of hydraulic system reliability analysis shows that the present method has strong uncertain information processing ability and polymorphism analysis ability. The analysis results verify the effectiveness of the proposed method.

Abstract:In order to improve the accuracy of the speed control of the shield hydraulic propulsion system and reduce the deviation between the mathematical model and the actual system, a dynamic system parameter identification method based on the time delay neural network and the upper and lower bounds of the system parameters is proposed. On the basis of establishing the speed control model of shield hydraulic propulsion system, the neural network is used to identify the indefinite parameters of the system within the range of parameters to be identified, and search for a set of parameters closer to the actual shield propulsion system to meet the system input. The actual system output can be accurately obtained for the actual signal. Finally, another set of sampled data of the shield simulation test bench is used to verify the system identification results. The results show that the model obtained by the identification method can approximate the real physical system.

Abstract:In order to realize the optimization of the robot path under the dynamic complex environment, on the basis of the establishment of the grid map model, aiming at the disadvantage of the traditional genetic algorithm, one is to make the path more smooth by improving the fitness function, and the second is to combine the improved genetic algorithm with the Morphin algorithm, so that the robot can effectively avoid the obstacle in real time. The simulation results show that by combining the improved genetic algorithm and the Morphin algorithm, the robot can quickly and safely reach the target point along a short and smooth optimal path.

Abstract:The application of advanced control theory and intelligent optimization algorithm in actual production is an effective way to further improve the coiling temperature control accuracy of hot strip. A genetic algorithm for parameter intelligent design is proposed in this paper based on the design of two new genetic operations, eugenic and atavistic. And it is applied in the coiling temperature prediction system based on Genetic Neural Network. Using the historical data of the hot rolling operation department of a steel mill, the model was trained and in-line tested and the simulation results of MFC (Microsoft Base Class Library) show that the coiling temperature prediction system has high precision and fast convergence speed. It can not only improve the quality of hot rolled strip products, but also provide strong technical support for the development of high-end and high value-added strip products.

Abstract:The purpose of the paper is to greatly improve the natural frequency of the embedded co-cured composite damping structure and optimize its stiffness. The embedded co-curing damping composite structure was taken as the research object. The natural vibration characteristics of the structure and the cruciform stiffener structure were compared and analyzed by the finite element method. The influence of the reinforcement width and height on the natural frequency of the structure was obtained. The results show that the reinforced rib could greatly improve the natural frequency and stiffness of the thin plate structure. The natural frequencies of the reinforced thin plate structure get increased with the increase of the rib height, and the first order natural frequency increases the most. Increase of the width of the ribs could increase the natural frequencies of the thin plates. When the width of the rib is large, the increase of the natural frequency could be reduced.

Abstract:Generally speaking, due to the excitation of the road and the engine, the fracture of exhaust system often occurs and affects the NVH index of the vehicle. In this paper, through the establishment of structural model of bellows and dynamic model of rubber pendants, the key components and main parameters, which have the biggest influence on vibration characteristics, are determined. Finally, take the fracture fault of a manifold catalytic converter as an example, low cycle fatigue and thermal fatigue analysis are carried out based on CAE and the improvement scheme has been put forward. In addition, the exhaust system of the vehicle is analyzed by modal analysis, the original suspension point position could be modified according to the analysis results. The results show that the fracture fault has been solved and the vibration characteristics of the exhaust system have been optimized.

Abstract:For the performance testing of pressure sensor in construction machinery, a hydraulic test rig for pressure sensor performance testing is designed based on LabVIEW and electro-hydraulic proportional loading technology. The composition and function of the test rig are introduced. The pressure loading process is analyzed on the basis of hydraulic schematic diagram. The static and dynamic performance curves of the pressure sensor are obtained by industrial computer, data acquisition card and LabVIEW. The measured pressure sensor are calibrated by a high-precision pressure sensor so that the performance of the testing pressure sensor could be are obtained.

Abstract:The grating micro/nano structure and square column array micro/nano structure with different structures are constructed on the surface of 100 crystal surfaces by removing the unit cell. At the same time, the Molecular Dynamics (MD) numerical simulation method combined with the hydrophobic structure model is used to establish the structure model suitable for grating and square column array micro/nano structure. The relationship between the theoretical contact angle and the contact angle of the simulation measurement has been compared and analyzed. The experimental results are verified from the micro scale, and the effect of the two structural parameters on the surface hydrophobicity is obtained. The results show that under the premise of removing one cell, the contact angle of the micro and nano structure of the square column array is 131°， and the hydrophobicity of the square column array microstructures is stronger. On the other hand, under the condition of CassieBaxter model, the hydrophobicity increases with the increase of the spacing width of hydrophobic structure, and decreases with the increase of hydrophobic structure width.

Abstract:The current aircraft ground air conditioning environment is complicated.There are few efficient methods targeting the online traffic detection problem.This paper proposed an online flow detection method of noncontact ultrasonic gas flowmeter DSP and FPGA processing system based on DSP chip of T1 company, which is responsible for controlling the flow in the process of detection and processing of ultrasonic signal the selected FPGA chip. Altera group is responsible for the completion of the ultrasonic transducer excitation and receiving signal high frequency sampling design of aircraft ground air traffic monitoring system.The feasibility and adaptability of the method wasproved by tests.

Abstract:In order to achieve high-quality and high-efficiency production in the mold manufacturing process, based on energy efficiency and surface quality, the objective function model is optimized, and the non-dominated sorting genetic algorithm is used for parameter optimization. The Cr12MoV die steel material was selected for the orthogonal experiment of single-step dry milling, and the optimized Pareto solution set was obtained through the experimental results. Considering the narrowing of selection range of optimization results to improve the reasonable accuracy of the CNC milling scheme, analytic hierarchy process is used to evaluate and analyze optimized parameter combination scheme. The results show that the application of AHP can be used to obtain the best target parameter combination scheme, which can realize high efficiency and high quality processing in the process of CNC machine tool processing.

Abstract:In this paper, the curvature of pure rolling single arc gear was analyzed according to the principle of differential geometry. The mean curvature and Gaussian curvature of pure rolling single arc gear were deduced systematically, and the relative curvature radius of pure rolling single arc gear was obtained. The influence of different parameters of pure rolling single arc gear on pure rolling single arc gear was analyzed by MATLAB. Based on the elastic contact theory, the tooth contact stress of pure rolling single arc gear transmission was calculated, and the influence of main parameters on the tooth contact stress of pure rolling single arc gear was investigated, which is of great significance for the design and manufacture of the following pure rolling circular arc gear.

Abstract:Aiming at the problems of low recognition accuracy and poor recognition effect of traditional meter reading methods, this paper presents a numerical recognition method of intelligent meters based on Region-based Convolutional Neural Network (R-CNN). This method first collects the image information of the digital code disc of the ammeter by camera, then preprocesses the collected images, and finally automatically recognizes the preprocessed images through R-CNN. The experimental results show that the proposed method in this paper could identify the position information automatically and read information of the dial simultaneously using R-CNN, which will greatly reduce the pressure of manual meter recognition and improve the accuracy of meter recognition.

Abstract:In this study, the ablation of aluminum sheets under single pulse femtosecond laser with different energy densities was studied. To simulate data map by using finite difference method and study the relationship between laser energy density and ablation, the femtosecond laser ablation experiment results were combined with two-temperature model. The ablation process of femtosecond laser belongs to non-equilibrium ablation. According to the simulated data, the surface electron temperature and lattice temperature could be directly observed during the ablation process of aluminum sheets. The thermal relaxation in the whole laser-ablation process was furthermore studied. The electro acoustic interaction under femtosecond laser ablation with different energy densities was studied. The correlation between energy density and femtosecond laser ablation was revealed based on the simulated results. Through analysis of the experimental data, it could be concluded that the femtosecond laser energy density, the processing efficiency and the quality of the processed aluminum materials were the three significant factors. Moreover, it could be found that with the increase of femtosecond laser energy density, the thermal relaxation process of femtosecond laser ablation was elongated, the ablation strength was enhanced to some extent, and the appearance quality of the processed materials could be improved. Therefore, it is of great importance to study the femtosecond laser ablation of materials.

Abstract:A stand-alone photovoltaic (PV) power system with storage batteries is designed. Power from PV modules is sent to the load on the DC bus through a DC-DC converter, and a bidirectional converter is used for storage batteries. The storage batteries will be charged when the power from PV modules is more than the power that load needs; Storage batteries provide power for load when the power from PV modules is less than the required. Adopt the maximum power point tracking algorithm to ensure PV modules provide the maximum power under certain conditions. In terms of software, this paper describes the control procedure in the whole and gives the algorithm and software design flow chart. The simulation model is built based on MATLAB/Simulink. The simulation and experimental results prove the rationality and feasibility of stand-alone PV power system.

Abstract:Torque converter is widely used in all kinds of transmissions such as cars, buses, wind turbines and engineering machinery. Due to poor accuracy and adaptability, the traditional design method no longer suits the needs of torque converter design and optimization, and 3D flow field simulation is widely used in torque converter design. With the increasing interest in the coupling of computational fluid dynamics and modern optimization techniques, an urgent need in finding an appropriate algorithm in torque converter design has risen. To this end, this paper employed four popular algorithms to optimize the performance in terms of blade numbers on a response surface. We compared and contrasted the algorithms in terms of the ability of searching for global optimum and handling constraints. The results indicated that AMGA exhibited the best search ability which is mainly attributed to the use of a large external archive. NSGA II outperformed the other algorithms in handling constraints. Due to the use of neighborhood crossover, NCGA has difficulties converging to global optimum as well as preserving diversity. No optimizer is clearly best overall, but this study demonstrated the merits and drawbacks of each optimizer and this may help the designer in choosing an appropriate algorithm considering their actual needs.

Abstract:In order to improve the efficiency of automated logistics control system, a hybrid algorithm was used to realize path planning based on path optimization. In the model design, the warehouse container had been designed to the matrix arrangement for the obstaclefree driving of the automatic guided vehicle. The model was built according to the number of the container and the physical location of the container. In the path planning design of the automatic guided vehicle, the objective function was solved by combining the fuzzy algorithm with the heuristic algorithm. Experiments showed that, compared with ant colony algorithm and simulated annealing algorithm, this algorithm had obvious advantages in solving the optimal solution and convergence, and had strong applicability in path optimization.

Abstract:With the advent of the era of big data, the amount of global information data is growing explosively. The information data with rapid growth contain endless value. Big data information processing technology could help people discover knowledge and find rules from massive data, so as to create application value. But with the rapid development of social economy, the basic big data information processing technology has been unable to meet the higher and higher requirements of massive data processing. The emergence and development of cloud computing technology could provide a solution for big data information processing technology to meet the requirements of users for efficient processing of diversified massive data. The combination of artificial intelligence, big data and cloud computing is an inevitable trend of social development, and the research of big data information processing technology based on cloud computing becomes very important. Therefore, in order to improve the efficiency of information processing and maintain the accuracy of data, the existing classical data analysis algorithm model and cloud computing technology are combined in this paper. So some research is done on massive information processing technology based on big data and cloud computing, and a big data information processing method based on cloud computing and cloud computing is proposed.

Abstract:In order to solve the influence of thermal deformation on spindle life and machining accuracy, the temperature rise characteristics of high-speed motorized spindle was studied. Firstly, the thermal structure coupling model of motorized spindle was established, then the thermal simulation was carried out by using ANSYS software, and the distribution of steady-state temperature field and the thermal deformation of motorized spindle were analyzed. Finally, the influence of the change of spindle speed and cutting force on the temperature of motorized spindle was discussed. The results indicate that the method can effectively simulate the distribution of temperature field and thermal deformation in the working process of the motorized spindle, and the simulation results are basically consistent with the experimental results, which provide a reference for the temperature control of the motorized spindle.

Abstract:Micro-expression is the real expression of human emotional expression. In the process of animation production, both two-dimensional animation and three-dimensional animation need to simulate the real person’s facial expression as much as possible. Micro expression animation key frame nesting refers to the formation of simulated micro expression graphics on the basis of referring to real micro expression data. The key frame of graphics is inserted twice on the basis of the existing key frame sequence of expression animation, and the facial expression is simulated finely. Based on the data of human facial micro expression database, this paper creates and inserts the key frame data. The experimental results are more vivid than those without inserting the key frame of micro expression. The simulation accuracy of animation is higher and more impressive. This method has certain practical value for improving the effect of two-dimensional animation, three-dimensional animation and VR(i.e., Virtual Reality) simulation of human face animation.

Abstract:Video streaming transmission process shows a low bandwidth usage efficiency in the P2P IPTV applications, an adaptive video streaming transmission algorithm of P2P IPTV is proposed to resolve this problem. Firstly, the target problem is formulated as a multi-segment streaming PSNR maximization problem, the target problem is solved directly through a dynamic programming algorithm; then, the optimal class subscription and class transmission strategy are selected to maximize the total video quality of the important region in the video segment; lastly, a new request model is designed to handle the unrecoverable data transmission, if it exists the unrecoverable media data in the important region of the receive node, it will periodically broadcast its buffer map as a request signal to all neighboring nodes, so that the unrecoverable data transmissions will be filtered. Experimental results based on the standard H.264/SVC video sequence show that the proposed algorithm could improve the bandwidth usage rate of P2P network streaming, and the received videos of the clients will realize a high quality.

Abstract:In order to improve the smoothness of the manipulator operation and achieve the precision of the manipulator control, the BP neural network and the ant colony algorithm are combined to realize the manipulator trajectory control. Firstly, the manipulator trajectory model is established, and then the main parameters of the manipulator are trained by the neural network algorithm. Then, the predicted trajectory of the output is compared with the expected trajectory of the manipulator to solve the optimal parameters closer to the expectation. Finally, the neural network model parameters are optimized by the ant colony algorithm. Experiments show that compared with the traditional BP neural network algorithm, the angular displacement of the proposed algorithm is more fitting with the expected angular displacement, and the displacement error in the spatial three-dimensional coordinate system is smaller.

Abstract:This paper is devoted to study the time delays in the control method for congested traffic. Based on the Full Velocity Difference Model, the stability analysis is performed based on general Nyquist stability criterion for the uncontrolled and controlled models which consider the time delays. The simulation results show that the proposed control scheme which considers the time delay can be competent to alleviate traffic congestion, and it could be verified by the theoretical results.