Deutsch
 
Hilfe Datenschutzhinweis Impressum
  DetailsucheBrowse

Datensatz

 
 
DownloadE-Mail
  Estimation of missing cone data in three-dimensional electron microscopy

Barth, M., Bryan, R. K., Hegerl, R., & Baumeister, W. (1988). Estimation of missing cone data in three-dimensional electron microscopy. Scanning Microscopy, Suppl., no., 2, 277-284.

Item is

Externe Referenzen

einblenden:

Urheber

einblenden:
ausblenden:
 Urheber:
Barth, M., Autor
Bryan, R. K., Autor
Hegerl, R.1, Autor           
Baumeister, W.1, Autor           
Affiliations:
1External Organizations, ou_persistent22              

Inhalt

einblenden:
ausblenden:
Schlagwörter: Eigenvalues and eigenfunctions; Electron microscopy; Entropy; Extrapolation; Picture processing; Electron and ion microscopes and techniques [A0780]
 Zusammenfassung: The range of tilt angles for which projected images of two-dimensionally periodic specimens can be obtained in electron microscopy is limited both by technical aspects such as goniometer design, and by the more fundamental limitation of object thickness. The lack of a full set of projections causes a missing cone in the reciprocal space data for the object, which will give an anisotropic resolution in a three-dimensional reconstruction and may cause the quality to be impaired by spurious features. The problem is governed by a linear operator which maps the three-dimensional object onto the set of projections. The eigenvalue spectrum of this operator is determined by the range of tilt angles and the spatial extent of the object. With restricted angle data some of the eigenvalues are extremely small, the problem is 'ill-conditioned' or sensitive to small perturbations such as noise, and it is necessary to regularize the solution. The authors applied two methods of band-limited extrapolation and inference on electron microscope data. Alternating projections onto convex sets regularized by a regularization parameter and a least squares estimation regularized by the Shannon entropy functional yield similar results if a close object extent constraint is available. The criterion of maximum entropy, however, allows relaxation of this constraint. (34 References).

Details

einblenden:
ausblenden:
Sprache(n):
 Datum: 1988
 Publikationsstatus: Erschienen
 Seiten: -
 Ort, Verlag, Ausgabe: -
 Inhaltsverzeichnis: -
 Art der Begutachtung: -
 Identifikatoren: eDoc: 318489
 Art des Abschluß: -

Veranstaltung

einblenden:

Entscheidung

einblenden:

Projektinformation

einblenden:

Quelle 1

einblenden:
ausblenden:
Titel: Scanning Microscopy, Suppl., no.
Genre der Quelle: Zeitschrift
 Urheber:
Affiliations:
Ort, Verlag, Ausgabe: -
Seiten: - Band / Heft: 2 Artikelnummer: - Start- / Endseite: 277 - 284 Identifikator: -