Unmanned Aerial Vehicles (UAVs) are a popular platform for air quality measurements. For vertical measurements, rotary-wing UAVs particularly well-suited. However, an important concern with is how the rotor-downwash affects measurement accuracy. Measurements from recent field campaign showed notable discrepancies between data ascent and descent, which suggested UAV downwash may be cause. To inv...

Objective: Cone beam computed tomography (CBCT) is applied for the imaging of the maxillofacial and dental structures, particularly for surgical treatments and dental implants. The aim of this study was to assess the effect of slice thickness on the accuracy of CBCT linear measurements. Methods: In this diagnostic accuracy study, forty-two titanium pins with the same dimensions were inserted...

The three-dimensional CMKF-D with only position measurements is extended to solve the radar target tracking problem with range-rate measurements, where the errors between range and range-rate measurements are correlated. Firstly, a pseudo measurement is constructed by the product of range and range-rate measurements to reduce the high nonlinearity of the range-rate measurements with respect to ...

introduction: during radiotherapy, high accuracy in the dose delivery is required because there is a strong  relationship between the absorbed dose, local tumor control and particularly the normal tissue damage. in  many institutions, in vivo dosimetry using diodes is performed to check the actual dose delivered. in general,  the uncertainty in the dose delivered should fall within  ± 5% of the...

We present a simple two-mode telemetry procedure which eliminates cyclic errors, to allow accurate absolute distance measurements. We show that phase drifts and cyclic errors are suppressed using a fast polarization switch that exchanges the roles of the reference and measurement paths. Preliminary measurements obtained using this novel design show a measurement stability better than 1 micron. ...