Generic,efficient and isochronous Gaussian sampling over the integers

Gaussian sampling over the integers is one of the fundamental building blocks of lattice-based cryptography.Among the extensively used trapdoor sampling algorithms,it is ineluctable until now.Under the influence of numerous side-channel attacks,it is still challenging to construct a Gaussian sampler that is generic,efficient,and resistant to timing attacks.In this paper,our contribution is three-fold.First,we propose a secure,efficient exponential Bernoulli sampling algorithm.It can be applied to Gaussian samplers based on rejection samplings.We apply it to FALCON,a candidate of round 3 of the NIST post-quantum cryptography standardization project,and reduce its signature generation time by 13–14%.Second,we develop an isochronous Gaussian sampler based on rejection sampling.Our Algorithm can securely sample from Gaussian distributions with different standard deviations and arbitrary centers.We apply it to PALISADE(S&P 2018),an open-source lattice-based cryptography library.During the online phase of trapdoor sampling,the running time of the G-lattice sampling algorithm is reduced by 44.12%while resisting timing attacks.Third,we improve the efficiency of the COSAC sampler(PQC 2020).The new COSAC sampler is 1.46x-1.63x faster than the original and has the lowest expected number of trials among all Gaussian samplers based on rejection samplings.But it needs a more efficient algorithm sampling from the normal distribution to improve its performance.

Visual Perception-Based Fault Diagnosis in Froth Flotation Using Statistical Approaches

Froth flotation is an important mineral concentration technique.Faulty conditions in flotation processes may cause the huge waste of mineral resources and reagents,and consequently,may lead to deterioration in terms of benefits of flotation plants.In this paper,we propose a computer vision-aided fault detection and diagnosis approach for froth flotation.Specifically,a joint Gabor texture feature based on the Copula model is designed to describe froth images;a rejection sampling technique is developed to generate training sets from the quality distribution of real flotation products,and then an isolation forest-based fault detector is learned;and a fault diagnosis model based on spline regression is developed for root cause identification.Simulation experiments conducted on the historical industry data show that the proposed strategy has better performance than the alternative methods.Thereafter,the entire framework has been tested on a lead-zinc flotation plant in China.Experimental results have demonstrated the effectiveness of the proposed method.