On the Impact of Inverse-Based dropping on ILUs derived from direct methods
نویسنده
چکیده
In this paper we present a new incomplete LU decomposition which is based on an existing sparse direct solver. In contrast to many incomplete LU decompositions this ILU incorporates information about the inverse factors L−1 and U−1 which have direct influence on the dropping strategy. We demonstrate in several large scale examples that this implementation constructs a robust preconditioner.
منابع مشابه
Multilevel Preconditioners Constructed From Inverse-Based ILUs
This paper analyzes dropping strategies in a multilevel incomplete LU decomposition context and presents a few of strategies for obtaining related ILUs with enhanced robustness. The analysis shows that the Incomplete LU factorization resulting from dropping small entries in Gaussian elimination produces a good preconditioner when the inverses of these factors have norms that are not too large. ...
متن کاملILU and IUL factorizations obtained from forward and backward factored approximate inverse algorithms
In this paper, an efficient dropping criterion has been used to compute the IUL factorization obtained from Backward Factored APproximate INVerse (BFAPINV) and ILU factorization obtained from Forward Factored APproximate INVerse (FFAPINV) algorithms. We use different drop tolerance parameters to compute the preconditioners. To study the effect of such a dropping on the quality of the ILU ...
متن کاملSevere Impact on the Behavior of Energy Absorbing Cylindrical Base in Frontal Impact
In this paper, the vibration characteristics of multi-layer shell that internal and external surfaces with a layer of piezoelectric sensor and actuator is investigated. The backrest shell laminated with simple analytical method to evaluate and the results were compared with results obtained by other researchers. The numerical solution methods (GDQ) for shells with piezoelectric layers and plain...
متن کاملImpact of physical criteria on thermal performance of different types of historical Houses in Hamedan City
As one of the oldest cities in Iran, Hamedan is thousands of years old. The oldest houses in Hamedan date back to the time of the Ashkaneniads. Archeological excavations discovered in the 1990s, the remnants of these houses in Hegmataneh hill. Houses belonging to the era before the Qajar dynasty are rare in Hamedan. However, there are plenty of architectural structures belonging to the Qajar er...
متن کاملروشهای تجزیه مقادیر منفرد منقطع و تیخونوف تعمیمیافته در پایدارسازی مسئله انتقال به سمت پائین
The methods applied to regularization of the ill-posed problems can be classified under “direct” and “indirect” methods. Practice has shown that the effects of different regularization techniques on an ill-posed problem are not the same, and as such each ill-posed problem requires its own investigation in order to identify its most suitable regularization method. In the geoid computations witho...
متن کامل