This paper presents recursion unrolling, a technique for improving the performance of recursive computations. Conceptually, recursion unrolling inlines recursive calls to reduce control flow overhead and increase the size of the basic blocks in the computation, which in turn increases the effectiveness of standard compiler optimizations such as register allocation and instruction scheduling. We...

Datalog systems evaluate joins over arithmetic (in)equalities as a naive generate-and-test of Cartesian products. We exploit aggregates in a source-to-source transformation to reduce the size of Cartesian products and to improve performance. Our approach approximates the well-known propagation technique from Constraint Programming. Experimental evaluation shows good run time speed-ups on a rang...

Collaborative filtering (CF) is a recommendation technique that analyzes the behavior of various users and recommends items preferred by with similar preferences. However, CF methods suffer from poor accuracy when user preference data used in process sparse. Data imputation can alleviate sparsity problem substituting virtual part missing In this paper, we propose k-recursive reliability-based (...

This paper reviews P´olya urn models and their connection to random trees. Basic results are presented, together with proofs that underly the historical evolution of the accompanying thought process. Extensions and generalizations are given according to chronology: • P´olya-Eggenberger’s urn • Bernard Friedman’s urn • Generalized P´olya urns • Extended urn schemes • Invertible urn schemes ...

This paper describes the application of the recursive parameter estimation technique used to detect the abrupt changes in the signals recorded during disturbances in the power network of South Africa. The recursive identification technique uses M parallel Kalman filters. Main focus has been to estimate the time-instants of the changes in the signal model parameters during the pre-fault conditio...

We present a technique for deriving incremental implementations for a subclass of algebraic speciications, namely, conditional well-presented primitive recursive schemes. We use concepts of the translation of well-presented primitive recursive schemes to strongly non-circular attribute grammars, storing results of function applications and their parameters as attributes in an abstract syntax tr...

We propose a methodology of reducing the space requirements of recursive procedures without destroying their fundamental recursive structure. This technique is quite general, and seems to apply to most recursive procedures, particularly those dealing with recursive data structures. A recursive procedure is transformed into three procedures – a shell which is called from the outside, and has the...