spiral scan

spiral scan

spiral scan
A radar scan pattern in which the beam is rotated out from and back to the centerline in a circular motion in the vertical plane. This pattern is applicable to target acquisition radars, providing range, relative azimuth, and elevation data.
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The patients underwent image acquisition in the electrocardiogram (ECG)-triggered sequential scan mode, retrospective ECG-gated spiral scan mode, or high-pitch spiral scan mode, as appropriate.
The reason for the choice of spherical spiral scanning case, notwithstanding its less effectiveness from the data reduction and measurement time saving viewpoints with respect to the helicoidal and planar spiral scan, is due to the fact that such a scanning, as the spherical one, allows the reconstruction of the whole AUT radiation pattern.
The NF-FF transformation with spherical spiral scan [28], using the two-bowls modelling (Fig.
Siemens' unique Adaptive Dose Shield addresses the issue by dynamically blocking the unnecessary dose before and after the spiral scan, ensuring that the only dose applied to the patient is dose that is clinically relevant.
The parachute rotates the canted submunition, producing a spiral scan of the ground.
The spiral scan is like a conical scan, except that the angle of the cone increases or decreases, as shown in Figure 2.
- +/- 30 degree tilt with the possibility of spiral scan, which is necessary to teach and research the optimal skanprotokoller for cerebralskanning.
The parameters such as pitch, collimation width, and table speed are related in a spiral scan process and affect the imaging quality outcome and radiation dose to the patients by varying degrees.
The results of the test injection are used to set injection parameters for the main spiral scan. The bolus tracking method uses software to automatically analyze contrast enhancement at an anatomic location specified in the particular examination protocol and to automatically begin the CT acquisition at a preset time after the enhancement at that location reaches a predefined threshold.
* The practice of taking overlapping scans in conventional CT for high-quality 3-D displays is replaced by the ability to calculate arbitrarily many overlapping images from 1 spiral scan without renewed exposure.
The system also features the company's Adaptive Dose Shield technology, which is designed to dynamically block any unnecessary radiation dose before and after the spiral scan.
In the data studied the next day, it was clear that each spacecraft had seen several flashes of light during the spiral scans, indicating both LRI instruments received light from the opposite spacecraft and were working as expected.