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Exposure assessment is the process of estimating or measuring the magnitude, frequency and duration of exposure to an agent, along with the number and characteristics of the population exposed. Ideally, it describes the sources, pathways, routes, and the uncertainties in the assessment.
The linear no-threshold model (LNT) is a dose-response model used in radiation protection to estimate stochastic health effects such as radiation-induced cancer, genetic mutations and teratogenic effects on the human body due to exposure to ionizing radiation. The model assumes a linear relationship between dose and health effects, even for ...
frequency analysis If a consequence is dependent on dose, i.e. the amount of exposure, the relationship between dose and severity of consequence must be established, and the risk depends on the probable dose, which may depend on concentration or amplitude and duration or frequency of exposure.
The United States Environmental Protection Agency defines NOAEL as 'an exposure level at which there are no statistically or biologically significant increases in the frequency or severity of adverse effects between the exposed population and its appropriate control; some effects may be produced at this level, but they are not considered as adverse, or as precursors to adverse effects. [5]
Exposure is a combination of the length of time and the illuminance at the photosensitive material. Exposure time is controlled in a camera by shutter speed, and the illuminance depends on the lens aperture and the scene luminance. Slower shutter speeds (exposing the medium for a longer period of time), greater lens apertures (admitting more ...
In radiometry, radiant exposure or fluence is the radiant energy received by a surface per unit area, or equivalently the irradiance of a surface, integrated over time of irradiation, and spectral exposure is the radiant exposure per unit frequency or wavelength, depending on whether the spectrum is taken as a function of frequency or of wavelength.
SAR measures exposure to fields between 100 kHz and 10 GHz (known as radio waves). [2] It is commonly used to measure power absorbed from mobile phones and during MRI scans. The value depends heavily on the geometry of the part of the body that is exposed to the RF energy and on the exact location and geometry of the RF source.
Frequency estimation is the process of estimating the frequency, amplitude, and phase-shift of a signal in the presence of noise given assumptions about the number of the components. [10] This contrasts with the general methods above, which do not make prior assumptions about the components.