Publications by authors named "J J Stamnes"

We present, to the best of our knowledge, a new method for retrieval of aerosol optical depth from multichannel irradiance measurements. A radiative transfer model is used to simulate measurements to create the new aerosol optical depth retrieval method. A description of the algorithm, simulations, proof of principle, merits, possible future developments and implementations is provided.

View Article and Find Full Text PDF

The total ozone column amount (TOCA) values from the Ozone Monitoring Instrument (OMI) derived from OMI/Aura ozone (O3) differential optical absorption spectroscopy (DOAS) V003 (OMDOAO3) have been validated against the ground-based TOCA values derived from Dobson and the Norwegian Institute for Air Research UV measurements in Kampala (0.31º N, 32.58º E, 1200 m), Uganda, for the period between 2005 and 2018.

View Article and Find Full Text PDF

Combining information from several channels of the Norwegian Institute for Air Research (NILU-UV) irradiance meter, one may determine the total ozone column (TOC) amount. A NILU-UV instrument has been deployed and operated on two locations at Troll research station in Jutulsessen, Queen Maud Land, Antarctica, for several years. The method used to determine the TOC amount is presented, and the derived TOC values are compared with those obtained from the Ozone Monitoring Instrument (OMI) located on NASA's AURA satellite.

View Article and Find Full Text PDF

Background: The detection of melanoma poses a substantial challenge, particularly for primary care providers (PCPs) who may have limited training in discriminating between suspicious and benign melanocytic lesions. The noninvasive optical transfer diagnosis (OTD) method was designed to be used by PCPs in their decision-making process.

Objectives: To assess the potential of the OTD method by developing, training and validating an OTD indication algorithm for automated discrimination between benign melanocytic lesions and malignant lesions, based on a set of 712 lesions.

View Article and Find Full Text PDF

A method is presented for discriminating between malignant and benign pigmented skin lesions based on multispectral and multi-angle images. It is discussed how to retrieve maps of physiology properties and morphometric parameters from recorded images using a bio-optical model, radiative transfer calculations, and nonlinear inversion, and how to employ automated zooming to extract lesion and surrounding masks. Training and validation of a classification scheme for separation between benign and malignant tissue yielded sensitivity/specificity ranging from 97%/97% for application to a small dataset comprised of lesions not used for training and validation to 99%/93% for application to a larger dataset.

View Article and Find Full Text PDF