A variable step-size selection method for implicit integration schemes

Author(s):  
R. Holsapple ◽  
R. Iyer ◽  
D. Doman
2011 ◽  
Vol 255-260 ◽  
pp. 2159-2163
Author(s):  
Jian Xiao Zou ◽  
Cui Yun Zhou ◽  
Gang Zheng

A new variable step-size numerical algorithm for implicit integration is discussed in this paper. The scheme for increase and decrease of step size is discussed according to the difference of output variable value. The next step size is calculated through the variable coefficient method and the limitation rules. The convergence and accuracy are testified by the simulation result. Compared with the common used ode45 algorithm, the algorithm has more computing efficiency with a certain calculation precision.


Author(s):  
Alberto Carini ◽  
Markus V. S. Lima ◽  
Hamed Yazdanpanah ◽  
Simone Orcioni ◽  
Stefania Cecchi

2019 ◽  
Vol 67 (6) ◽  
pp. 405-414 ◽  
Author(s):  
Ningning Liu ◽  
Yuedong Sun ◽  
Yansong Wang ◽  
Hui Guo ◽  
Bin Gao ◽  
...  

Active noise control (ANC) is used to reduce undesirable noise, particularly at low frequencies. There are many algorithms based on the least mean square (LMS) algorithm, such as the filtered-x LMS (FxLMS) algorithm, which have been widely used for ANC systems. However, the LMS algorithm cannot balance convergence speed and steady-state error due to the fixed step size and tap length. Accordingly, in this article, two improved LMS algorithms, namely, the iterative variable step-size LMS (IVS-LMS) and the variable tap-length LMS (VT-LMS), are proposed for active vehicle interior noise control. The interior noises of a sample vehicle are measured and thereby their frequency characteristics. Results show that the sound energy of noise is concentrated within a low-frequency range below 1000 Hz. The classical LMS, IVS-LMS and VT-LMS algorithms are applied to the measured noise signals. Results further suggest that the IVS-LMS and VT-LMS algorithms can better improve algorithmic performance for convergence speed and steady-state error compared with the classical LMS. The proposed algorithms could potentially be incorporated into other LMS-based algorithms (like the FxLMS) used in ANC systems for improving the ride comfort of a vehicle.


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