Background & Aims of the Study: Noise is one of the most important environmental pollutants. It is a global health problem, especially among industrial workers. Since there was little information about noise levels in small workshops in Qom city, this study aimed to evaluate noise in small workshops and compare it with national standards. Materials and Methods: This was a cross-sectional stu...

  Background: Educational centers have higher standards for controlling noise pollution as it has been shown that noise pollution is a major cause of discomfort for teachers and students. Noise pollution reduces concentration, interferes in the conversation, and leads to dropouts and lower grades especially in mathematics. The present study aimed to evaluate noise pollution in the schools ...

the aim of this paper is to minimize output phase noise for the pure signal synthesis in the frequency synthesizers. for this purpose, first, an exact mathematical model of phase locked loop (pll) based frequency synthesizer is described and analyzed. then, an exact closed-form formula in terms of synthesizer bandwidth and total output phase noise is extracted. based on this formula, the phase ...

Conflict of interest: non existent certain cognitive and emotional aspects2-4. This kind of handicap hinders access to and use of healthcare in general, yielding potential adverse effects on health and survival5. The prevalence of hearing loss is on the rise in the population at large, probably because of the ageing of the population and increased exposure to noise. There are concerns that hear...

the equivalent noise level in large cities has been growing due to the population growth, uncontrolled production of cars, and the existence of worn out cars. on the other hand, heavy traffic has increased the amount of noise problems for residents of medical and educational centers, research institutes and residential area (or sensitive centers to noise) built in highway bounds and it has also...

Chip-level substrate coupling analysis uses F-matrix computation with slice-and-stack execution to include highly concentrated substrate resistivity gradient. The technique that has been applied to evaluation of device-level isolation structures against substrate coupling is now developed into chip-level substrate noise analysis. A time-series divided parasitic capacitance (TSDPC) model is equi...

Abstract – In this paper, we have studied an ICS repeater based on OFDM system considered with phase noise effects by using Simulink. In wireless repeater system, in case of same frequency for transmitted and received signals, the feedback interference signal, which comes into the receive antenna from the transmit antenna of a radio repeater, causes the radio repeater go into feedback oscillati...

rotaviruses group a are the major cause of diarrhea in calves under one month and every year causes enormous economic losses. serological and molecular techniques can be used for rapid detection of rotaviruses but virus isolation requires specific methods of cell culture and suitable cell lines. in this study, 41 samples were collected from diarrheal calves up to the age of one month, from indu...

this study has been carried out with the objective of isolation and identification of agent(s) of pasteurella pneumonia in sheep and goat in iran using bacteriological and biochemical assays to be identified in the pursuant researches to be used in pasteurellosis vaccine production. to accomplish this objective, samples were gathered from areas suspicious to pasteurellosis infection and industr...