fiducial point

fiducial point

[fə′dü·shəl ‚pȯint]
(optics)
A mark, or one of several marks, visible in the field of view of an optical instrument, used as a reference or for measurement. Also known as fiduciary point.
References in periodicals archive ?
The fiducial point of the R-wave was identified by an algorithm of parabolic interpolation and a derivative plus threshold algorithm to locate a stable and noise-independent reference point.
We define three different temporal windows with respect to the location of the heartbeat fiducial point (FP) as shown in Figure 3(b).
Constraints of 0.0001 m were applied to station positions of the fiducial point in order to reference the network solutions to the ITRF2005.
Images were captured immediately adjacent to a single external fiducial point to ensure that the fields from each section corresponded.
The important fiducial point at [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] is the Schwarzschild radius [r.sub.s] = 2[mr.sub.*]/[m.sub.*], where
Analysis of the slope estimated over the ECG signal segments will be used for the ECG fiducial point detection.
Preoperatively, fiducial points are annotated in the medical images or graphic models of the bones, and intraoperatively, the same points are located in the bones of the patient using a navigated tool [12].
The P-QRS-T waves were investigated and employed to extract the fiducial points in real-time and adaptive techniques for the detection and delineation of furthermore, seven features that characterize the different intervals of the ECG signal were take out and used that data feed to the naive Bayes to classify the each heartbeat as normal or abnormal.
Figure 3 shows an example of the fiducial points on a frontal face (the original image is from Chicago Face Database [24] which is publicly released image database).
In view of that, those 12 fiducial points were far from the reservoir bank and they were set into the bedrock; we preliminarily treated the fiducial points as relatively stable points.
Even though there are methods of obtaining the HRV by detecting R peaks in the electrocardiographic signal (ECG) which have proved to be accurate and reproducible [20] [21] [22] [23] [24] [25] [26] [27], there is no much information regarding the methods for obtaining the HRV from the construction of pulse to pulse time-series based on detecting fiducial points in the PPG signal [15] [17] [19].
If the machine head cannot locate the fiducial points, component placement may be impossible.