This paper models the influence of the morphology of an object on the accuracy of the scanned data, for the case of contactless laser scanning. Using the scanned objects morphology, two important process parameters ar...
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This paper models the influence of the morphology of an object on the accuracy of the scanned data, for the case of contactless laser scanning. Using the scanned objects morphology, two important process parameters are specified namely scanning angle and distance of the laser beam from the part surface. Experiments have been performed with different scanning conditions using full factorial design. A mathematical prediction model for estimating the standard deviation of the final surface is developed in terms of the above scanning parameters using response surface methodology (RSM). Furthermore, analysis of variance (ANOVA) has been employed to establish the statistical significance of the scanning parameters and the developed model. In addition, it has been observed that the measured and predicted standard deviations are well in agreement, which confirms the effectiveness of the developed model. The mathematical model is further optimized using a modifiedparticleswarm optimization (MPSO) algorithm. The proposed MPSO algorithm generates new swarm positions and fitness solutions using an improved and modified search equation. Finally, two realistic non-trivial case studies are considered for validation of the proposed methodology. This methodology provides the optimal combination of morphological process parameters with a considerable reduction in standard deviation for final scanned surface models. (C) 2017 Elsevier Ltd. All rights reserved.
The accurate parameter estimation for Muskingum model is to be useful to give the flood forecasting for flood control in water resources planning and management. Although some methods have been used to estimate th...
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The accurate parameter estimation for Muskingum model is to be useful to give the flood forecasting for flood control in water resources planning and management. Although some methods have been used to estimate the parameters for Muskingum model, an efficient method for parameter estimation in the calibration process is still lacking. In order to reduce the computational amount and improve the computational precision for parameter estimation, a modified particle swarm algorithm (MPSO) is presented for parameter optimization of Muskingum model. The technique found the best parameter values compared to previous results in terms of the sum of least residual absolute value. Empirical results that involve historical data from existed paper reveal the proposed MPSO outperforms other approaches in the literature.
The set of measured data points acquired from the Coordinate Measuring Machine (CMM) need to be processed and analyzed for evaluating the form errors inside the manufactured components. This paper presents a modified ...
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The set of measured data points acquired from the Coordinate Measuring Machine (CMM) need to be processed and analyzed for evaluating the form errors inside the manufactured components. This paper presents a modifiedalgorithm of particleswarm optimization (MPSO) for assessing the form error from the set of coordinate measured data points. In the classical algorithm of the particleswarm optimization (PSO), the value of the candidate solution is updated from its existing value without actually comparing the value obtained in the consecutive iterations for fitness. This behaviour attributes to a lack of exploitation ability in the defined search space. The proposed algorithm generates new swarm position and fitness solution for the objective function through an improved and modified search equation based on a proposed heuristic step. In this step, the swarm searches around the best solution of the previous iteration for improving the swarm exploitation capability. The particleswarm uses greedy selection procedure to choose the best candidate solution. A non-linear minimum zone objective function is formulated mathematically for different types of form errors and then optimized using proposed MPSO. Five benchmark functions are used to prove the effectiveness of the modifiedalgorithm, which is verified by comparing its solution and convergence with those obtained from the established algorithms namely PSO and genetic algorithm (GA). Finally, the result of the proposed algorithm for form error evaluation is compared with previous work and other established nature-inspired algorithms. The results demonstrate that the proposed MPSO algorithm is more efficient and accurate than the other conventional heuristic optimization algorithms. Furthermore, it is well suited for form error evaluation using CMM acquired data.
According to the characteristics of aero-engine's accelerating process, the control parameters and constraints are determined for the optimal acceleration control. A non-linear programming model is established to ...
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ISBN:
(纸本)9781424467129
According to the characteristics of aero-engine's accelerating process, the control parameters and constraints are determined for the optimal acceleration control. A non-linear programming model is established to the optimal acceleration control for a certain turbofan engine, which high pressure rotor speed and high pressure turbine inlet temperature, are as the objective function of accelerating control. From two factors, increasing the diversity of particleswarm and accelerating the convergence speed, the particleswarmalgorithm has been modified. By judging the particle properties, the particleswarmalgorithm has be expanded from the feasible region to the entire solution space. The optimization simulation of control laws is performed using the modifiedparticleswarm optimization for a turbofan engine's accelerating process. Results show that the algorithm has a strong border search capability and the engine's accelerating abilty has been enhanced.
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