AECG is an important carrier of information about time scan cyclic electrophysiological processes in the heart, which are the concentrated expression potsiklovye (from cycle to cycle) changes in the length of RR-intervals or, more conveniently, HR.
In the quasi-stationary conditions (quiet, rhythmic physical and / or mental activity) the duration of RR-intervals (HR) fluctuates around a mean value. These fluctuations are called heart rate variability (HRV).
In the transition from rest to stress (physical to physical stress to mental mental stress, including different combinations), the health of a disease from one phase of the disease to other phases for recovery, if it is possible, exacerbations and remissions RR-interval duration (HR) is usually shortened or, respectively, increases (change back) heart rate. These changes are called transients.
Fluctuations in the length of RR-intervals (HR) around some mean value in quasi-stationary conditions, changes in the characteristics of these fluctuations, the direction and the nature of deterministic changes in transients are the result, and therefore the carrier of information on the state of the regulatory functions of the human body.
Defence
http://www.bksv.com/multifield
Brüel & Kjær 4961 - Multi-field-microphone
The only microphone you will need in multi-fields -- free, diffuse or unpredictable sound fields. Ideal for any situation where the nature of the sound field is unpredictable, or if the direction of the dominant noise source is difficult to pinpoint, or shifts over time -- such as measuring in cabins in the automotive and aerospace industries.
A revolution in microphone technology, this is the world's first ¼" measurement microphone that can guarantee that your measurements are accurate and error-free in free or diffuse sound fields and at any angle. It is also well-suited to complex spaces with non-stationary or multiple sources that need to be measured in one go.
Uses:
Measurements in unpredictable sound-field conditions
Cabin noise measurements
Near-field measurements
Ad hoc sound measurements
Features:
Sensitivity: 60 mV/Pa
Frequency range: 5 Hz -20 kHz
Dynamic range: 20 -130 dB
TEDS: UTID No. 769
Temperature: -20 to +80°C (-4 to +176°F)
Connects directly to DeltaTron® (CCLD) input