Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Neuroradiology 40 (1998), S. 277-282 
    ISSN: 1432-1920
    Keywords: Key words Stereotaxic techniques ; Angiography ; digital subtraction ; Therapeutic radiology ; Image processing ; computer assisted
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract An algorithm for correction of the geometrical distortion in digital subtraction angiography (DSA) images was developed. Originally invented for 3D X-ray angiography, the algorithm was implemented in a computer program designed to fulfil the specific needs of stereotaxic DSA. The algorithm is based on transformation of an image of a grid from a distorted image back into its original pattern. The same transformation is then applied pixel-by-pixel to the angiographic images, which are acquired in direct conjunction with the grid image, without moving the gantry. The algorithm was tested in phantom studies and in the clinical situation with seven patients in ten examinations. Comparisons were made between co-ordinate determinations made on conventional full-size cut film and those performed on uncorrected and corrected DSA images, using 30- and 23-cm fields of view. With our method of measurement we could not show any remaining geometric distortion in the corrected DSA images. This distortion correction can, if properly applied, be used for high-precision stereotaxic DSA.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Empirical economics 22 (1997), S. 431-460 
    ISSN: 1435-8921
    Keywords: Labor supply ; Monte Carlo simulation ; C15 ; J22
    Source: Springer Online Journal Archives 1860-2000
    Topics: Economics
    Notes: Abstract In the area of labor supply and taxes advanced microeconometric methods have been developed in order to measure wage and income elasticities. Large variations in estimated elasticities have previously been reported in the literature. The purpose of the present study is to assess the sources for these discrepancies, and propose a robust estimator. According to our findings the commonly used maximum-likelihood estimator is sensitive to measurement errors in those variables that are needed in order to construct the individuals' budget sets. An iterative least squares estimator is preferred in small samples under several forms of specification and measurement errors.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...