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Focused on the problems that low-precision and easily to fall into local optimum result in the high-dimensional space by the longhorn search algorithm,this paper proposed a new optimization algorithm of the short-lived beetles-the shortlived search algorithm based on quadratic interpolation which was called QIBAS.The algorithm took tentacle’s left and right tentacles as interpolation coordinate points after the beetle moved.And it generated new solution with a second interpolation,then compared to the current optimal solution and the global optimal solution with the fitness of interpolation solution.At the same time to update the global optimal solution,it performed numerical simulation tests on multiple unimodal and multimodal functions,and their dimensions took as 100,500,1 000,5 000 and 10 000.The simulation results show that the introduction of quadratic interpolation effectively improves the ability of the BAS algorithm to jump out of the local optimum.When QIBAS solves the optimal value,its solution accuracy is greatly improved,and the convergence speed is also significantly improved.The effectiveness of the improved algorithm is verified. [ABSTRACT FROM AUTHOR]

This paper presents a novel real-time (online) interpolation algorithm based on Finite Impulse Response (FIR) filters to generate smooth and accurate reference motion trajectories for machine tools and motion systems. Typically, reference tool-paths are composed of series of linear (G01) or circular (G02) segments. Basic point-to-point (P2P) feed motion can be generated by interpolating each segment with trapezoidal or S-curved velocity profile. However, smooth and accurate transitions between path segments are necessary to realize non-stop contouring motion. In this study, FIR filters are utilized, and the reference tool-path is filtered to interpolate a non-stop rapid feed motion. By using a chain of FIR filters, acceleration and jerk continuous motion profiles are generated from velocity pulse commands. A segment interpolation timing technique is developed to control the contour errors during non-stop real-time interpolation of tool-paths. Furthermore, by utilizing FIR filters for interpolation, frequency spectrum of the interpolated motion profiles is controlled. The time constant (delay) of the filter is tuned to create notches around the lightly damped vibration modes of the motion system, which allows mitigation of unwanted vibrations and thus enables delivering accurate feed motion. Simulation studies and industrial scale experimental validations are provided to illustrate effectiveness of the developed interpolation technique. [ABSTRACT FROM AUTHOR]

Loewner matrix (LM) interpolation-based macromodeling methods can generate an accurate macromodel for large and complex structures. However, there is less flexibility in the choice of the macromodel order due to the need to ensure passivity. In this paper, an algorithm is proposed to obtain a reduced order model based on LM interpolation while still maintaining the passivity of the macromodel. This is achieved by first relaxing the passivity requirement during the order selection process; then a new passivity enforcement scheme with significantly improved speed and convergence properties is applied. The proposed approach results in a significantly reduced macromodel size while maintaining accuracy and passivity conditions. The efficiency of the new approach is shown in the examples. [ABSTRACT FROM PUBLISHER]

In this paper, an effective diffusion coefficient derived from previous semi-empirical formula and dynamic grid technology combined with inverse distance interpolation algorithm are applied to simulate wind-induced snow drifting on low-sloped gable roofs. The effective diffusion coefficient enhances the diffusion ability of particles near the wall surface, and the inverse distance interpolation algorithm has an explicit format, which determines the influence of the sample point on the interpolation point according to the interpolation distance, it has a low computational expense and weakens the influence of extreme points. Two measurement parameters, δ H and δ M , are introduced to illustrate the impact of interpolation parameters (power law p and interpolation radius R) on the single grid adjustment and snow cover. By employing these optimisations, sensitivity analyses for simulation parameters are performed, the effects of the saltation layer height, turbulent Schmidt number, falling velocity, time step size, and wind duration on snow distribution are discussed. Finally, the redistributions of snow cover on gable roofs under various wind directions are reproduced, the snow redistribution characteristics and the relationship between roof slope and snow erosion are investigated. The results can provide a reference for predicting snow loads on gable roofs. • A numerical simulation method with a revised diffusion term is proposed, which can enhance the diffusion ability of particles near the wall surface effectively. • This method and simulation parameters are validated by scaled model experiments. • The impact of simulation parameters is analysed in details. • The redistributions of snow cover on gable roofs under various wind directions are reproduced, the snow redistribution characteristics are investigated. [ABSTRACT FROM AUTHOR]

Contemporary land information systems allow the generation of models of numerical surfaces by applying a number of interpolation algorithms. The appropriate selection of measurement points included in the calculations is one of the key factors influencing the quality and accuracy of interpolation. Properly selected points contribute to improving the accuracy of the generated surface models and to shortening the computation process. This paper analyzes the effect of the location and density of measurement points on the accuracy of interpolation surfaces in view of the morphological differentiation of the generated models. [ABSTRACT FROM AUTHOR]