MATHEMATICAL ENGINEERING TECHNICAL REPORTS Index Reduction for Differential-Algebraic Equations by Substitution Method
نویسندگان
چکیده
Differential-algebraic equations (DAEs) naturally arise in many applications, but present numerical and analytical difficulties. The index of a DAE is a measure of the degree of numerical difficulty. In general, the higher the index is, the more difficult it is to solve the DAE. Therefore, it is desirable to transform the original DAE into an equivalent DAE with lower index. In this paper, we propose an index reduction method for linear DAEs with constant coefficients. This is applicable to all DAEs having at most one derivative per equality, and always reduces the index exactly by one. Our method is different from other existing methods in that it does not introduce any additional variables.
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