Research on acoustical hoods used in industry has been widely discussed; however, the assessment of shape optimization on space-constrained close-fitting acoustic hoods by adjusting design parameters has been neglected. Moreover, the acoustical performance for a one-layer acoustic hood used in a high intensity environment seems to be insufficient. Therefore, an assessment of an optimally shaped acoustical hood with two layers will be proposed. In this paper, a numerical case for depressing the noise level of a piece of equipment by optimally designing a shaped two-layer close-fitting acoustic hood under a constrained space will be introduced. Furthermore, to optimally search for a better designed set for the multi-layer acoustical hood, an artificial immune method (AIM) has been adopted as well. Consequently, this paper provides a quick and effective method to reduce equipment noise by optimally designing a shaped multi-layer close-fitting acoustic hood via the AIM searching technique.

During the years of observations pedatory arthropods of Arachnida, Chrysopidae, Heteroptera, Coccinellidae, and Syrphidae were collected from Myzocallis coryli Goetze colonies. Arachnida constituted the most numerous group followed by predatory bugs of Heteroptera.

Boron nitride thin layers were produced by means of the pulsed laser deposition technique from hexagonal boron nitride target. Two types of laser i.e. Nd:YAG with Q-switch as well as KrF coupled with RF generator were used. Influence of deposition parameters on surface morphology, phase composition as well as mechanical properties is discussed. Results obtained using Fourier Transformed Infrared Spectroscopy, Transmission and Scanning Electron Microscopy, Atomic Force Microscopy are presented. Micromechanical properties measured during microindentation, scratch and wear tests are also shown.