Fuzzy extractors (Dodis et al., Eurocrypt 2004) convert repeated noisy readings of a high-entropy secret into the same uniformly distributed key. A minimum condition for the security of the key is the hardness of guessing a value that is similar to the secret, because the fuzzy extractor converts such a guess to the key. We define fuzzy min-entropy to quantify this property of a noisy source of...

Moisture samples taken from the unsaturated zone with soil water extractors undergo degassing and an upward shift in pH. The measured pH values from commercially available extractors are usually sufficiently in error that they cannot be used in a quantitative manner. A model has been developed that predicts the extent of CO2 degassing and the resulting pH error. Using this model measured pH val...

We construct a strong extractor against quantum storage that works for every min-entropy k, has logarithmic seed length, and outputs Ω(k) bits, provided that the quantum adversary has at most βk qubits of memory, for any β < 1 2 . The construction works by first condensing the source (with minimal entropy-loss) and then applying an extractor that works well against quantum adversaries when the ...

In this paper a feature extractor based on Gabor frames and Mallat’s scattering transform, called Gabor scattering, is introduced. This feature extractor is applied to a simple signal model for audio signals, i.e. a class of tones consisting of fundamental frequency and its multiples and an according envelope. Within different layers, different invariances to certain signal features occur. In t...

In previous lectures we defined a randomness extractor as follow, Definition 1 Function Ext : {0, 1}n × {0, 1}d → {0, 1}m is (k, ε)extractor if for any distribution W ∈ {0, 1}n, with H∞(W ) ≥ k SD(Ext(W ; I), Um) ≤ ε. ♦ If (I,Ext(W ; I) ≈ε (I, Um) we say Ext is a strong extractor. We saw that if H = {hi : {0, 1}n → {0, 1}m|∀i ∈ {0, 1}d} is a universal hash family and m ≤ k − 2 log(1/ε) then Ext...

lawsone a natural pigment present in the henna leaves has been used as a skin and hair dye since 1400 bc. the concentration of this natural compound in leaves varies from place to place depending upon many of the environmental factors and the highest quantity reported so far is about 1% of the dry mass. heretofore, it has been reported that natural colored extracts and isolate from henna leaves...

Motivated by the problem of how to communicate over a public channel with an active adversary, Dodis and Wichs (STOC’09) introduced the notion of a non-malleable extractor. A non-malleable extractor nmExt : {0, 1} × {0, 1} → {0, 1} takes two inputs, a weaklyrandom W and a uniformly random seed S, and outputs a string which is nearly uniform, given S as well as nmExt(W,A(S)), for an arbitrary fu...

Given two independent weak random sources X,Y , with the same length l and min-entropies bX , bY whose sum is greater than l + Ω(polylog(l/ε)), we construct a deterministic two-source extractor (aka “blender”) that extracts max(bX , bY ) + (bX + bY − l − 4 log(1/ε)) bits which are ε-close to uniform. In contrast, best previously published construction [4] extracted at most 1 2 (bX + bY − l− 2 l...