Noise presents health and social problems in industrial operations, and is mainly related to machinery used in the industries. The present study was conducted in the different utilities industries in Jeddah Industrial Estate (JIE), in order to assess the magnitude of the problem of industrial noise exposure there in an endeavor to propose remedial controls to the problem. Noise was measured in ...

We propose a $B-L$ model combined with the $S_4\times Z_3\times Z_4$ discrete symmetry which successfully explains recent $3+1$ sterile - active neutrino data. The smallness of mass is obtained through type-I seesaw mechanism. active-active and sterile-active mixing angles are predicted to be consistent constraints in $0.3401\, (0.3402) \leq \sin^2\theta_{12}\leq 0.3415\, (0.3416), \, 0.456\, (...

introduction: the improvement of technology has increased noise levels in hospital wards to higher than international standard levels (35-45 db). higher noise levels than the maximum level result in patient’s instability and dissatisfaction. moreover, it will have serious negative effects on the staff’s health and the quality of their services. the purpose of this survey is to analyze the level...

‎darafsheh and assari in [normal edge-transitive cayley graphs on non-abelian groups of order 4p‎, ‎where $p$ is a prime number‎, ‎sci‎. ‎china math‎., ‎56 (1) (2013) 213-219.] classified the connected normal edge transitive and‎ ‎$frac{1}{2}-$arc-transitive cayley graph of groups of order $4p$‎. ‎in this paper we continue this work by classifying the‎ ‎connected cayley graph of groups of order...

In this paper, given a poset $(X,leq)$, we introduce some  drifts on a groupoid $(X,*)$ with respect to $(X,leq)$, and we obtain several properties of these drifts related to the notion of $Bin(X)$. We discuss some connections between fuzzy subalgebras and upward drifts.

Acousticians have industriously devised and refined metrics for measuring and predicting human responses to environmental noise such as sons, phons, noys, NC, NR, dB(A) dB(C), Leq, Ldn, and when rigorously applied in ISO standards offer effective reproducibility and repeatability, but they fall short when it comes to charting the vicissitudes of everyday listening and the communication of that ...