We call a family G ⊂ P[n] a k-generator of P[n] if every x ⊂ [n] can be expressed as a union of at most k disjoint sets in G. Frein, Lévêque and Seb˝ o [1] conjectured that for any n ≥ k, such a family must be at least as large as the k-generator obtained by taking a partition of [n] into classes of sizes as equal as possible, and taking the union of the power-sets of the classes. We generalize...

We call a family G ⊂ P[n] a k-generator of P[n] if every x ⊂ [n] can be expressed as a union of at most k disjoint sets in G. Frein, Lévêque and Sebő [1] conjectured that for any n ≥ k, such a family must be at least as large as the k-generator obtained by taking a partition of [n] into classes of sizes as equal as possible, and taking the union of the power-sets of the classes. We generalize a...

Differently from OLTP workloads, OLAP workloads are hardly predictable due to their inherently extemporary nature. Besides, obtaining real OLAP workloads by monitoring the queries actually issued in companies and organizations is quite hard. On the other hand, hardware and software benchmarking in the industrial world, as well as comparative evaluation of novel approaches in the research commun...

We call a family G ⊂ P[n] a k-generator of P[n] if every x ⊂ [n] can be expressed as a union of at most k disjoint sets in G. Frein, Lévêque and Seb˝ o [1] conjectured that for any n ≥ k, such a family must be at least as large as the k-generator obtained by taking a partition of [n] into classes of sizes as equal as possible, and taking the union of the power-sets of the classes. We generalize...

We show that modified versions of the linear congruential generator and the shift register generator are provably good for amplifying the correctness of a probabilistic algorithm. More precisely, if r random bits are needed for a BPP algorithm to be correct with probability at least 2/3, then O(r + k) bits are needed to improve this probability to 1 − 2−k. We also present a different pseudo-ran...

Assume from now on that X/K is a smooth proper geometrically connected curve of genus g, and consider the degree morphism deg : P(K)→ Z. The period δ′(X/K) of X/K is defined to be the positive generator of the image of the degree map P(K)→ Z. The index δ(X/K) is the positive generator of the image of the degree map Pic(X) → Z. We let γ(X/S) denote the positive generator of the image of the comp...

A parametric meshing technique is presented with special emphasis to singularities in the parametric mapping. Singularities are locations where the parametric mapping is highly distorted or even singular. In a NURBS context, this arises when control points are clustered into the same location in three dimensions. Limitations of parametric plane meshing in this context are highlighted, and zeroa...

High-energy surge tests have been pe$ormed on metal-oxide varistors of a type in common use, according to a proposed ZEC standard derived from German Standard W E 01 60. l%e surge generator used for the test was a prototype commercial device developed especially to deliver the 1000300 ps waveform speczjied by W E Standard 0160. Depending on the position of the varistor within its manufacturing ...