نتایج جستجو برای: light and noise
تعداد نتایج: 16914688 فیلتر نتایج به سال:
background: noise is one of the most important harmful agents in work environment. noise pollution in oil refinery industries is related to workers' health. this study aimed to determine the overall noise pollution of an oil refinery operation and its frequency analysis to determine the control plan for a vent noise in these industries. methods: this experimental study performed in control unit...
in recent years noise has been well known as an environmental pollution. particularly its effects will be more serious in some environments including hospitals which patients need a calm and peaceful condition. this study aims to evaluate hospitals noise pollution level. this study is a cross-sectional study. noise measurements were made in all hospital wards in a workday and weekend from 8 to ...
Background and Aim: Noise is the most common source of environmental stress that influences negatively the psychological and physiological aspects of human. The purpose of this study was determining the noise sources and assessing in General Intensive Care Unit. Materials and Methods: In this cross-sectional study, equivalent noise level "Leq 15 min", Maximum and Minimum sound pressure level we...
Besides the physical limits imposed on photon absorption, the coprocessing of visual information by the phototransduction cascade and photoreceptor membrane determines the fidelity of photoreceptor signaling. We investigated the response dynamics and signaling efficiency of Drosophila photoreceptors to natural-like fluctuating light contrast stimulation and intracellular current injection when ...
The 1/f noise investigation in nanoscale light-emitting diodes and lasers, based on GaAs and alloys, is presented here. Leakage and additional (to recombination through quantum wells and/or dots) nonlinear currents were detected and it was shown that these currents are the main source of the 1/f noise in devices studied. Keywords—Lasers, light-emitting diodes, quantum dots, quantum wells, 1/f n...
Background and Aim: Combined exposure to noise and temperature can affect the neurophysiological responses of the office staff. The present study was done to investigate the impacts of combined exposure to noise and low air temperature on physiological responses and environmental comfort. Methods: In this experimental study, the studied population included the students who were randomly selecte...
Rapid development of spin noise spectroscopy of the last decade has led to a number of remarkable achievements in the fields of both magnetic resonance and optical spectroscopy. In this report, we demonstrate a new - magnetometric - potential of the spin noise spectroscopy and use it to study magnetic fields acting upon electron spin-system of an n-GaAs layer in a high-Q microcavity probed by e...
This study has been carried out in two shoe-making factories in Tehran with the aim ofevaluating the cobined effects of noise and toluene on the workers' hearing. Sixty four workers were assigned to three groups according to their exposure to noise andtoluene. 33 were exposed to noise (group 0), 5 to toluene (group 1) and 26 to noise andtoluene (group 2).The concentration were measured in the ...
Background and Objective : Noise is considered as a common occupational health hazard in a wide range of occupational settings including oil and gas industries and related companies. This research aimed to assess the environmental noise and personal exposure in a petrochemical plant. Method: First, environmental noise measurement was performed as recommended by ISO9612 (1997) and next, shor...
Maximum number of excitation light sources Dependent on the fiber diameter: in general, only one due to the small fiber diameter. Using 5 mm diameter LEDs and a 10 cm long fiber, it is possible to accomodate a total of 20 light sources increasing the amount of signal accordingly. Amount of excitation light available Available from the evanescent wave tail which is a very small portion of the to...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید