A limiting factor in many molecular dating studies is shortage of reliable calibrations. Current methods for choosing calibrations (e.g. cross-validation) treat them as either correct or incorrect, whereas calibrations probably lie on a continuum from highly accurate to very poor. Bayesian relaxed clock analysis permits inclusion of numerous candidate calibrations as priors: provided most calib...

An inevitable task before direct georeferencing can be performed is the calibration of the GPS/IMU system and the imaging sensor. The permanent calibration fields for largeand medium-scale (1:3 300 – 1:16 000) system calibration constructed by Finnish Geodetic Institute are described in this article. Theoretical results concerning the effect of block structure on the accuracy and determinabilit...

Camera calibration is an important step in 3D reconstruction of scenes. Many natural and man made objects are circular and form good candidates as calibration objects. We present a linear calibration algorithm to estimate the intrinsic camera parameters using at least three images of concentric circles of unknown radii. Novel methods to determine the projected center of concentric circles of un...

A single calibration film method was evaluated for use with intensity-modulated radiation therapy film quality assurance measurements. The single-film method has the potential advantages of exposure simplicity, less media consumption, and improved processor quality control. Potential disadvantages include cross contamination of film exposure, implementation effort to document delivered dose, an...

It is shown that genetic inversions can be used to recover lognormal aerosol size distributions from multiangle optical scattering cross-section data measured by a polar nephelometer at a wavelength of 0.532 mm. The inversions can also be used to recover the absolute calibration factor of the polar nephelometer. The method is demonstrated by applying it to polar nephelometer data measured durin...

The primary science instrument of the CloudSat Mission is the Cloud Profiling Radar (CPR). The CPR is a W-band (94 GHz) nadir looking radar (e.g. Tanelli, 2008) with the purpose of measuring backscattered power from hydrometeors (clouds and precipitation). Although the CPR contains an internal calibration system, external calibration using geophysical sources with known normalized radar cross-s...

Lumped conceptual rainfall runoff models have been widely used in hydrology for many years. These models are usually able to describe most important processes in a catchment through a set of solvable equations. Thus, in many cases they are preferably over full physically-based models since they have such advantages: basic physicallybased and simplicity. However, many parameters of these models ...

UNLABELLED This study investigated the feasibility of quantitative accuracy and harmonized image quality in (89)Zr-PET/CT multicenter studies. METHODS Five PET/CT scanners from 3 vendors were included. (89)Zr activity was measured in a central dose calibrator before delivery. Local activity assays were based on volume as well as on the local dose calibrator. Accuracy and image noise were dete...

We present in this paper a novel calibration method that uses cross ratio t o compute world points falling onto any given light stripe plane of a structured light system. We show that, by using 4 known non-coplanar sets of 3 collinear world points, the direct 4 x 3 imageto-world transformation matrix for each light stripe plane can also be recovered from plane-to-plane homography. Preliminary e...

We present an open-source MATLAB toolkit for ultrasound calibration. It has a convenient graphical user interface which sits on top of an extensive API. Calibration using three different phantoms is explicitly supported: the cross-wire phantom, the single-wall phantom, and the Hopkins phantom. Image processing of the Hopkins phantom is automated by making use of techniques from binary morpholog...