Search PubMedSearch

PubMed · 512114

Tomographic reconstruction from limited angular data.

Abstract

The nth moment of a projection Mn(phi) = rnp(r, phi) dr must be a trigonometric polynomial of degree less than or equal to n. Measuring Mn(phi i) for n + 1 arbitrary angles phi i allows reconstruction of Mn(phi) for all phi. Thus in principle, the exact knowledge of the shadow function within an arbitrarily narrow sector allows reconstruction of the complete shadow. The algorithm doing this is very simple, but its applicability is severely limited by noise in the data.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A Peres. 1979. Tomographic reconstruction from limited angular data.. https://pubmed.ncbi.nlm.nih.gov/512114/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Dielectric noise in membranes.

Most theoretical and experimental studies of electrical fluctuations in membranes so far have been devoted to noise associated with conduction processes. In this paper a different type of noise is described which results from dipolar transitions in the membrane. Two mechanisms for the generation of such dielectric noise are analyzed: (a) conformational transitions of membrane proteins involving changes in dipolar moment and/or polarizibility, and (b) rotation of dipolar molecules dissolved in the lipid. The spectral intensity of current noise calculated for the two models exhibits a characteristic dependence on frequency omega with a decrease proportional to omega 2 towards low frequencies and an approach to a frequency-independent (white noise) limit at high frequencies. For a given number of dipolar molecules in the membrane, the spectral intensity is inversely proportional to the square of the membrane thickness.

Mathematics