The modern internal combustion engine (ICE) has to meet several requirements. It be reliable with the reduced emission of pollutant gasses and low maintenance What is more, it efficient both at low-load high-load operating conditions. For this purpose, a variable turbine geometry (VTG) turbocharger used provide proper acceleration exhaust gases Such solution also In paper, result an unsteady, t...

It is a classical result of Mortimer that L 2 , rst-order logic with two variables, is decidable for satissability. We show that going beyond L 2 by adding any one of the following leads to an undecidable logic: very weak forms of recursion, viz. (i) transitive closure operations (ii) (restricted) monadic xed-point operations weak access to cardinalities, through the HH artig (or equicardinalit...

The general theory of bivariate orthogonal polynomials goes back to the work of Jackson [12]. Special examples have arisen in studies related to symmetric groups [4, 16, 22]), as extensions of one variable polynomials [7, 15] and as eigenfunctions of partial differential equations [19, 14, 13, 21]. An updated account of the theory can be found in the books [5, 25]. A major difficulty encountere...

Effect of Statements Every element E ∈ E(X) can be considered as description of the set γ(E) of the concrete states x ∈ Z with x |= E. Likewise, the best description α(X) of a setX ⊆ Z of states is the conjunction of all equalities e with x |= e for all x ∈ X . Together, α and γ form a Galois connection between (2Z k ,⊆), the powerset of the set of states ordered by inclusion, and (E(X),⇒). ACM...

We consider bivariate real valued polynomials orthogonal with respect to a positive linear functional. The lexicographical and reverse lexicographical orderings are used to order the monomials. Recurrence formulas are derived between polynomials of different degrees. These formulas link the orthogonal polynomials constructed using the lexicographical ordering with those constructed using the re...