Papers by Keyword: Response Surface Method (RSM)

Abstract: This study reports the statistical optimization of experiments, designed by Taguchi, to improve the wear-resistance of the tungsten carbide/cobalt-based coatings applied using high-velocity oxygen-fuel (HVOF) spraying processes. In this study, a group of needlelike textures appeared in the HVOF WC-Co coatings. The structures were evenly distributed and compacted closely, showing a more dense and homogenous configuration. The coating that formed with a large amount of pores, microcracks and unmolten particles was much looser, and the interface was locally prone to defects. The coatings were obviously not homogenous. Experimental results show that the wear-resistant coatings are highly dense, with an elastic lamellar structure. The tribological properties were significantly improved and the surface textures showed uniformity, in a molten droplet flattened formation. A homogenous, morphological structure, with local small aggregation, was more obvious after HVOF WC-Co coating. Accordingly, it is clear that the surface properties determined proved favorable to the mechanical properties of the WC/Co coatings. In addition, we compared the linear models with the quadric models, using RSM methods, in all the experiments. Statistically, the linear models produced an average error of 8.285％, while the quadric models generated an average error of 1.399％. It is clear that the RSM models successfully fitted the HVOF WC-Co coating process and the quadric models yielded more accurate predictions than the linear models, in most cases. The proposed procedure was applied to HVOF spraying of WC-CO coatings. The results demonstrated its feasibility and its effectiveness in improving the HVOF WC-Co coating.

Abstract: A new improved multidiscipline feasible (MDF) strategy based on the updating approximate function constructed by Response Surface Method (RSM) is firstly pointed out and denoted as MDF-update-RSM which involves double cycles. Before the start of inner loop on MDF-update-RSM strategy, the approximate function is initialized by RSM on a set of sampling points which are generated from the Design of Experiment (DOE). With the process of outer loop, the coefficients and one high-order term of polynomial are updated and upgrade by the Least Square Regression. The ability of this new strategy promotes the efficiency and saves huge calculational cost incurred by the MDF strategy which always runs on the multidisciplinary analysis (MDA). The MDF-update-RSM is good procedure to ameliorate the accuracy that has been tested by the Rosenbrock function in this paper. Finally, the optimization strategy is employed on executing the low pressure turbine shrouded blade design and provides a true optimal result compared to the classical MDF strategy.

Abstract: Crashworthiness is one of the most important characteristics in automobile design, which is inflected by a large number of different factors, the influences of all these factors on crashworthiness are not identical. In order to screen the factors which influence the crashworthiness of the automobile most remarkablely, the graphics analysis method of the unreplicated saturated factorial design was employed. It is more and more widely used in the screening of factors because of its huge benefit in economic and the technical reason. The paper applied half-normal probability plot method to get the active and sensitive factors, and D-optimal design was employed to choose design sample points. The full quadratic polynomial approximation model was used to construct the response surface model of the internal energy. Finally, Multi-Island Genetic Algorithm was utilized to obtain the optimal solution of the multivariable crashworthiness optimization of the vehicle body under the full-scale frontal impact load.

Abstract: The sensitivity of blast pressure of a pressure vessel to the material strength, the effective welding depth and the relative radius is studied by finite element simulations and single-factor sensitivity analyses. And the sensitivity coefficients are obtained by normalization procession. Furthermore, a three-factor regression model is obtained by multi-factor numerical experiments. The investigation of this paper provides guidelines for further researches of relating problems.

Abstract: In order to determine the optimum joint conditions, four key process parameters affecting the joint quality of laser transmission joint of 1mm thick PET film and PC film，namely，laser power, scanning speed, clamping pressure and scanning number are optimized by response surface methodology in this paper. The interaction effect of main process parameters on joint quality is researched. The samples are tested using a multi-axis microtester in order to determine joint strength. The morphology of the joining area is observed with an optical microscope. Design Expert analysis indicates that the best laser power, scanning speed, clamping pressure and scanning number on joint quality were 35.7W, 5.0mm/s, 0.75MPa, 3, respectively. Finally, the experimental results are consistent with the predicted, which illustrates that the developed mathematical models can predict the responses adequately.

Abstract: It is difficult in finite element model(FEM) updating, because the essence is a mechanical anti-question solving. In the paper, the suppositional material method is utilized to model the FEM of a mirror frame system, and the required updating parameters are defined. The functions between the natural frequency and the updating parameters are established based on the response surface method. Based on the response surface model and the modal experiment results, the sum of absolute value of relative errors between the results of experiments and simulations is defined as the optimization objective, four required updating are identified automatically. The first three natural frequencies of updated mirror frame system are better accordant with the experiment results, which proves the method correct and reliable.

Abstract: The aim of this work was to optimize the process parameters through the statistical approach for the tingle and bot black bean. The process parameters influencing the tingle and bot black bean production were identified by using response surface methodology. The variables screened were most significant and showed a positive interaction. Optimum formula of spicy black beans could be achieved at pepper 3.125%, Chinese prickly 2.15%, and salt 3.035%. Such conditions resulted in score of 92.

Abstract: In this study, the goose meat was used as raw material and the formula of composite tender agent was optimized by Response Surface Methodology. Goose breast meat were soaked with exogenous protease of plants, phosphate and Ca2+ for 3 hours at 2 °C. The influence of different composite tender agent on the water-holding capacity was examined by statistical response surface methodology (RSM). The result showed that papain 6.16 U/g, compound phosphate 0.308 % and calcium chloride 0.133 % was helpful to increase the tenderization of goose breast. The results of our study would be used to improve the tenderness of goose meat and increase economic efficiency of goose industry.

Abstract: Urban flooding due to climate changes, dam breaking and drainage systems being overwhelmed by rainfall causes a huge loss to mankind civilization every year all over the world. This work aims to minimize the flooding damage by optimally design the building location and interspace. The velocity, water pressure and the height of water are considered as the main factors to reduce the flooding damage. The multi-objective optimization is implemented by combing several techniques, including Design of Experiment (DOE), Response Surface Method (RSM) and the Genetic Algorithm (GA). The proposed methodology is validated with a case study on the topography of ESTP Cachan.

Abstract: Response surface method has won numerous concerns in the reliability analysis of structure due to its simplicity and practicability, especially quadratic response surface taking no account of cross terms is most widely used. However, for the complex ultimate state curved surface corresponding to strongly nonlinear, the approximate accuracy of quadratic response surface is apparently not enough, causing a biggish error in estimation of reliability. Although, theoretically, higher order response surface method can resolve this problem, the sharp increase of undetermined coefficient reduces calculation efficiency, and even, cannot achieve. Therefore, on the basis of univariate analysis of multivariable function, an algorithm which can reasonably determine higher order response surface form is presented in this article, able to effectively reduce the number of undetermined coefficients in response surface, so as to reduce computational difficulties and put forward improving measures for possible problems; In addition, based on the tactics of number-theoretic setpoint, a type of scheme of number-theoretic selecting point applicable to response surface method has been developed. Finally, through the analysis of examples, the suggested algorithm was validated, with the result showing that the algorithm has good accuracy and efficiency.