A standard model of nonlinear combiner generator for stream cipher system combines the outputs of several independent Linear Feedback Shift Register (LFSR) sequences using a nonlinear Boolean function to produce the key stream. Given such a model, cryptanalytic attacks have been proposed by finding out the sparse multiples of the connection polynomials corresponding to the LFSRs. In this direct...

Before discussing multiplication, let us speak about addition. The number A(k) of distinct sums i+ j ≤ k such that 1 ≤ i ≤ k/2, 1 ≤ j ≤ k/2 is clearly 2 bk/2c − 1. Hence the number A(2n) of distinct elements in the n × n addition table involving {1, 2, . . . , n} satisfies limn→∞A(2n)/n = 2, as expected. We turn to multiplication. Let M(k) be the number of distinct products ij ≤ k such that 1 ≤...

Information distance is a parameter-free similarity measure based on compression, used in pattern recognition, data mining, phylogeny, clustering, and classification. The notion of information distance is extended from pairs to multiples (finite lists). We study maximal overlap, metricity, universality, minimal overlap, additivity, and normalized information distance in multiples. We use the th...

Wave-equation migration with the velocity of the primaries maps non-diffracted waterbottom multiples to an hyperbola in subsurface-offset-domain-common-image-gathers. Furthermore, for positive surface offsets, the multiples are mapped to non-positive subsurface offsets if sediment velocity is faster than water. The larger the offset in the data space, the larger the subsurface offset and the sh...

A 33 years old woman, treated for hypertension on monotherapy for a year, was admitted on emergency for sudden onset headache. Clinical examination revealed a conscious patient, blood pressure= 13/7, with the presence of frank meningeal syndrome, no fever. Cerebral CT showed subarachnoid hemorrhage at the right middle cerebral valley. The arteriography objectified three aneurysmal dilations at ...

dans une conception traditionnelle, l’intelligence est fixée et peut être mesurée par un nombre dans un contexte déconnecté de toute réalité et s’attribuer une forme unique. dans une vision nouvelle, en se basant sur la théorie des intelligences multiples de gardner, l’intelligence a  en revanche de différentes composantes et peut être développée  durant toute la vie. le présent article s’intro...