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Through the researches on various item improvements of particle swarm optimization algorithm, the improved particle swarm optimization algorithm is proposed for the insufficient global searching ability. This paper has improved the parameters of velocity formula and introduced new distance calculation formula to modify various parameters in the velocity formula. The improved particle swarm optimization algorithm has been tested by adopting standard test function, and the result has been compared with other particle swarm optimization algorithms. The experimental result indicated that the proposed improved particle swarm optimization algorithm in this paper got the better result for function optimization problems. [ABSTRACT FROM AUTHOR]

Facial recognition is a technique for biometric identification, generally applied to finance, cybersecurity, public security, property management, and other important management departments. In this paper, the facial recognition system based on improved LBP and PCA mathematical algorithm is used to extract the relationship between the facial centre point and other phase domain points. After using PCA to reduce the dimension, the facial features are obtained. The facial recognition system designed by the thesis covers face image creation, face image pre-processing, face image recognition and result output module. Studies have shown that the system's face recognition accuracy can be as high as 90%. [ABSTRACT FROM AUTHOR]

Parameter optimization and calibration of the hydrological model has been one of the important research fields in hydrological forecasting. This paper is written to address the inherent defects that traditional parameter optimization of Xinanjiang hydrological model with a single objective entails. These methods cannot fully exploit hydrological characteristics information from hydrological observation. We selected the Nash Sutcliffe coefficient, which is known to be biased for high flows and the logarithmic form of the Nash Sutcliffe coefficient that emphasize low-flow values as the objective functions. Then, we adopted the multi-objective optimization algorithms, such as the Nondominated Sorted Genetic Algorithm-II (NSGAII) and the Third Evolution Step of Generalized Differential Evolution (GDE3), and the single-objective optimization algorithm, Simulated Annealing (SA). These algorithms were applied in Heihe River Basin to calibrate parameters of the Xinanjiang hydrological model for long-term prediction of river discharges. Through the evaluation of the Pareto optimal parameter set derived from multi-objective optimization algorithms and the optimal solution obtained from the single objective algorithm, the results showed that the multi-objective optimization algorithms, in particular the NSGA-II algorithm, perform best to locate the Pareto optimal solutions in the parameter search space. They can also obtain better results with respect to the model parameters calibrated by the single objective algorithm. The major contribution of this work is the comparative application research of single-objective optimization with the multi-objective optimization algorithms for the parameters optimization of the Xinanjiang model in the Heihe River basin. [ABSTRACT FROM AUTHOR]

Optimization is often used to perform model calibration, the process of inferring the values of model parameters so that the results of the simulations best match observed behavior. It can both improve the predictive capability of the model and curtail the loss of information caused by using a numerical model instead of the actual system. At its heart is the comparison of experimental data and simulation results. Complicating this comparison is the fact that both data sets contain uncertainties which must be quantified in order to make reasonable comparisons. Therefore, uncertainty quantification (UQ) techniques can be applied to identify, characterize, reduce, and, if possible, eliminate uncertainties. Incorporation of UQ into the calibration process can drastically improve the usefulness of computational models. Current approaches are serial approaches in that first, the calibration parameters are identified and then, a series of runs dedicated to UQ analysis is completed. Although this approach can be effective,it can be computationally expensive or produce incomplete results. Model analysis that takes advantage of intermediate optimization iterates can reduce the expense, but the sampling done by the optimization algorithms is not ideal. In this paper, we will review serial approaches and propose a joint calibration and UQ approach that combines Bayesian statistical models and derivative-free optimization in order to monitor sensitivity information throughout the calibration process. [ABSTRACT FROM AUTHOR]

The measurement of diffusion coefficients in an orthotropic medium under conditions of concentration dependence is fraught with experimental complications. The author is developing an alternative measurement procedure, based on an inverse problem formulation. This paper discusses an evaluation of the computational program intended to process experimental measurements. Orthotropy and concentration dependence in the medium are incorporated in the model by the use of a Finite Elements, nested inside a non-linear optimization algorithm. An evaluation of results of test cases would indicate that the proposed methodology is viable. [ABSTRACT FROM AUTHOR]