This paper deals with a fundamental problem in motion and stereo analysis, namely that of determining the camera intrinsic calibration parameters. A novel method is proposed that follows the autocalibration paradigm, according to which calibration is achieved not with the aid of a calibration pattern but by observing a number of image features in a set of successive images. The proposed method ...

The two-by-two dot centering model enables predicting the spectral reflectance of color halftones and does not depend on a specific halftoning algorithm. It requires measuring the reflectances of a large number of two-by-two calibration tile patterns. Spectral measurement of hundreds or thousands of tile patterns is cumbersome and time consuming. In order to limit the number of measurements, we...

For event discrimination, operational implementation of a regional seismic station requires three sequential calibration analyses. 1) Magnitude, distance, and amplitude corrections (MDAC) made to observed regional amplitudes are necessary so that what remains in the corrected amplitude is mostly information about the seismic source-type. Corrected amplitudes can be used in ratios to discriminat...

Perfluorinated compounds are ubiquitous in the environment and have been reported to occur in human blood. Accurate risk assessments require accurate measurements of exposures, but identification and quantification of PFCs in biological matrices can be affected by both ion suppression and enhancement in liquid chromatography-tandem mass spectrometry techniques (LC/MS-MS). A study was conducted ...

Illumination conditions in images, such as shadows, can cause problems for both humans and computers. As well as shadows obscuring some features in images for human observers, many computer vision algorithms such as tracking, segmentation, recognition, and categorization are challenged by varying illumination. Previously, shadow removal algorithms were proposed that require recording a sequence...

The simultaneous determination of two carbamate pesticides (carbaryl and carbendazim) and of the degradation product of carbaryl (1-naphthol) in iceberg lettuce was achieved by means of PARAFAC decomposition and excitation-emission fluorescence matrices. A standard addition method for a calibration based on four-way data was applied using different dilutions of the extract from iceberg lettuce ...

In order to improve the precision and accuracy of the calibration results, there are two general effects should be considered. One of them is the definition of the mathematical model of the calibration problem with respect to the physical nature of the problem, and the other one is the statistical model of the estimation of the calibration parameters. The estimation procedure is important for b...

A technique for absolute end-to-end calibration of a fully polarimetric microwave radiometer is presented. The technique is based on the tripolarimetric calibration technique of Gasiewski and Kunkee, but is extended to provide a means of calibrating all four Stokes parameters. The extension is facilitated using a biaxial phase-retarding microwave plate to provide a precisely known fourth Stokes...

In order to improve the Tsai’s two-step camera calibration method, we present a camera model which accounts for major sources of lens distortion, namely: radial, decentering, and thin prism distortions. The coordinates of principle points will be calculated at the same time. In the camera calibration model, considering the errors existing both in the observation vector and the coefficient matri...

In this work a new algorithm is derived for the onboard calibration of three-axis strapdown magnetometers. The proposed calibration method is written in the sensor frame, and compensates for the combined effect of all linear time-invariant distortions, namely soft iron, hard iron, sensor non-orthogonality, bias, among others. A Maximum Likelihood Estimator (MLE) is formulated to iteratively fin...