Papers by Keyword: Parameter Optimization

Abstract: In this paper, the method to adjust the production process of polycarboxylic admixtures mother liquid is researched according to the production of polycarboxylic admixtures. One polycarboxylic admixture cannot be adapted to all cements because of the influence of the mother liquid, although it could be adjusted by composite stabilizer. This paper studies the method of parameter adjustment on the level of factor analysis according to the process of polycarboxylic admixtures. The fluidity of cement slurry test is carried out when the type of cement is changed. On the basis of the test results the parameters are analyzed to design the molecular structure of the polycarboxylic admixtures, which could solve the problem of compatibility between polycarboxylic admixture and cement fundamentally.

Abstract: Based on the emus' VIP test of floor shock absorber, the parameter optimizations are conducted. Through the experimental comparison and analysis of low stiffness with high damping, stiffness damping and the original car shock absorber, it proved that the high stiffness damping vibration damping performance is better than another two kinds of shock absorber.

Abstract: The accurate prediction model’s establishing of the blast furnace coke rate is important for optimizing the integrated production indicators of iron and steel enterprise. For the problem of accuracy of the model of coke rate, This paper established blast coke rate modeling with support vector machine algorithm, the model parameters of support vector machine was optimized by genetic algorithm, then a coke rate model based on support vector machine with the best parameters was built. Simulation results showed that: the forecasting model’s outcome, average absolute error and the mean relative error, was small which is based on genetic algorithm optimized SVM. coke rate model based on Genetic algorithm optimized support vector machine has high degree of accuracy and a certain practicality.

Abstract: For the difficulties of PID controller parameter optimization, we have put forward a novel depiction method PPOGS (PID Parameters Optimization based on Glowworm Swarm). By combining the minimum error absolute time integral definition proportion, the objective optimal functions of integral and differential functions, this method can produce the optimal allocation with the help of the glowworm swarm algorithm which seeks solution to the objective function. At last, we use MATLAB to make a simulation experiment, conducting an in-depth investigation of the key factors influencing the method. The results have showed PPOGS has better adaptability compared with other methods Key words: PID controller; parameter optimization; glowworm swarm; simulation

Abstract: Scarf repair parameters were optimized in this paper, to find the best repair parameter, and get better strength restoration effect. Composite laminates material was IM6/3501-6. Considering symmetry of structure, 1/4 repaired structure was taken as research object, to be built up finite element model and optimized for repair parameter. Element SOLID46 in software ANSYS was used to simulate main board and patch, element SOLID45 was used to simulate adhesive layer, to build up composite scarf repair finite element model. Because of small scarf repair angle and small ratio of adhesive layer thickness to composite laminate thickness, repair structure geometry was complex, to get exact calculation result, mesh was refined at place where stress is concentrated. There were 4488 element in the built up finite element model, with nodes number as 6263. Tsai-Wu rule and maximum shear stress was taken as failure criteria for composites laminate and adhesive layer respectively. With consideration on scarf ratio and adhesive layer thickness on repaired specimen strength, three dimension finite element models for scarf repair on composite laminates was constructed. Compared with experiment, it was found that finite element model agreed with experiment, thus validity of scarf repair model was proved. By Changing the value of each factor, finite element calculation of the repaired structure failure load showed that: the optimal value of scarf ratio is 1:20; influence of adhesive layer thickness of failure load of scarf repair structure is not obvious, generally 0.1mm meets the requirements; failure load increases when adhesive layer elastic modulus increases, but the rate of increase slows down gradually. Then the earliest failure site was analyzed according to finite element stress calculation result, failure process of adhesive layer was simulated, adhesive layer failure process was predicted, from 0 degrees to 45 degrees, and the adhesive layer top part first destroys, then spreads to 45 degrees to 90 degrees, and spreads to the adhesive layer lower end.

Abstract: Due to the complexity of the heat transfer for heating furnace, some characteristics are caused such as big inertia, great lag. In the temperature control system for heating furnace, the traditional PID controller can not get satisfactory effect, that dynamic is instability and control accuracy is bad, which is very detrimental to the system to achieve optimum efficiency. A fractional order PI^λD^μ controller based on particle swarm optimization method was designed, at the same time compared with PID control. Simulation results show that, fractional order PI^λD^μ control based on particle swarm optimization has better convergence stability, faster response times and higher accuracy value. Fractional order PI^λD^μ controller has better dynamic performance, compared with traditional PID controller, greatly improves the quality control system.

Abstract: A new type of vibration platform was presented and its dynamic characteristics was studied in this paper, A virtual prototype model of vibration platform was built by using software Soldworks and ADAMS.The flexible body model of spring was built based on ADAMS flexible module,rigid-flexible coupled dynamic of vibration platform were analyzed by using simulation, the natural frequency, model of vibration and frequency response were further analyzed. The stiffness of spring and flexible cable were optimized according to the analysis results, The post-optimality simulation results show that the stability and frequency response of vibration platform have improved.

Abstract: The randomness and intermittence of wind farm real power generation bring challenges to power system operation, and installing battery system for the mitigation of the fluctuation of wind farm output, following the short-term forecasting curve, even adjusting the output according to the operator’s requirement is a possible way to address the problem from the wind farm side. After a review of various storage control strategies for stabilizing the fluctuation of wind power output, the model of battery energy storage system as well as its control strategy is introduced. Adaptive Genetic Algorithm (AGA) is used for the optimization of PI control parameters. Simulation shows the effectiveness of the proposed method. Moreover, comparing with the trial-and-error method, the optimization algorithm proposed has the advantage of finding the optimal parameters under the lack of experience on PID control, and combined with trial-and-error method, the difficulties engineer could face on tuning the parameters of PI controller is decreased, which increases the feasibility for parameters of PI controller’s being transplanted to similar applications.

Abstract: In this study, the Taguchi method was utilized to determine the optimum process parameters for dissimilar friction stir welding between AA6061 and AA7075 aluminium alloys. The Taguchi L9 orthogonal array and optimization approach was applied on three levels of three critical factors, namely rotational speed, transverse speed and tool tilt angle. The optimum levels of process parameters were determined through the Taguchi parametric design approach. Through the parameter analysis, the predicted value of the dissimilar joint’s tensile strength was calculated to be 209.7 MPa, which is in close proximity to the experimental data (219.6 MPa) with 4.5% error. It can be concluded that a high tensile value of 219.6 MPa was achieved using 1000 rpm rotational speed, 110 mm/min travel speed and 3 ̊ tilt angle.

Abstract: Searching optimal PID parameters depends on the engineering experience and the experience is more time-consuming, less effective. In order to improve the efficiency of optimizing the PID parameters, propose a method of adaptive particle swarm optimization (APSO) to adjust inertia weight. During searching process, taking PID parameters as particles of particle swarm and the standard of ITAE is the performance index of error. If the algorithm is caught into the local optimal, then change the inertia weight. The simulation on the pitch channel of unmanned powered parafoil shows that the PID parameters of parafoil pitch channel controller which is adjusted by APSO have good effect. At the same time, the result can indicate that the PID parameters adjusted by APSO can improve tracking performance of the system, so that it has highly application value.