on the source of plasma density and electric field perturbations in pmse and pmwe regionspolar mesospheric summer/winter echoes (pmse/pmwe) are very strong radar echoes produced by ionospheric electron density fluctuations at half the radar wavelength. the main focus of this paper is the altitude range 80 to 90 km in summer and altitude range 65-86 km in winter in the polar mesosphere . this pa...

Contamination of pistachio nuts by aflatoxigenic strains of Aspergillus species is the greatest constraint to production and export of pistachio nuts in Iran, the leading producer of pistachio nuts in the world. Kerman province is the main region in Iran where 85%, of pistachio nuts are produced. Determining the population density of Aspergillus spores in the orchards and terminals which are th...

The combination of detections of anisotropy in cosmic microwave background radiation and observations of the large-scale distribution of galaxies probes the primordial density fluctuations of the universe on spatial scales varying by three orders of magnitude. These data are found to be inconsistent with the predictions of several popular cosmological models. Agreement between the data and the ...

Density fluctuations in traffic current are studied by computer simulations using the deterministic coupled map lattice model on a closed single-lane circuit. By calculating a power spectral density of temporal density fluctuations at a local section, we find a power-law behavior, ∼ 1/f, on the frequency f , in non-congested flow phase. The distribution of the headway distance h also shows the ...