Under summarizing the characteristics of pulse noise,the pulse coupled neural network(PCNN) is combined with gray-scale morphology,and a new pulse noise removing algorithm based on PCNN and gray-scale morphology is proposed.

An improved median filter algorithm which uses selected pixel method,theory of information entropy,is presented,which can effectively remove the random impulse noise and can also gives a concern restrains of other kind of noise.

According to the features of the pulse noise in digital image,a fast and effective algorithm of pulse noise fil-tering is proposed in this article.

Dielectric loss angle algorithm considering impulsive noise;

A robust subspace tracking method in impulsive noise environment;

Performance of bit-interleaved differentially coded modulation in fading and impulsive noise environment;

By analysing the causes of the machinery impact noise,the authors of this paper mainlydiscuss how to analyse it by the technique of impact stimulation both in theory and practice.

The impact noise excitation is discussed,and the time-history inputting models for impact noise excitations are founded.

Studied also are the noise spectrum characteristics and its relation with air pressure and intermittency during exhaust in addition to ways of eliminating impact noise.