In this paper we demonstrate how data encoded in a five-qubit quantum error correction code can be converted, fault-tolerantly, into a seven-qubit Steane code. This is achieved by progressing through a series of codes, each of which fault-tolerantly corrects at least one error. Throughout the conversion the encoded qubit remains protected. We found, through computational search, that the method...

Systems of forward-looking linear decision rules can be formulated as vector \rational" error correction models. The closed-form solution of the restricted error corrections is derived, and a full-information estimator is suggested. The error correction format indicates that the assumptions of convex adjustment costs and rational expectations impose di erent types of a priori restrictions on th...

objective(s): in spect, the sinogram contains scatter and lack of attenuated counts that degrade the reconstructed image quality and quantity. many techniques for attenuation and scatter correction have been proposed. an acceptable method of correction is to incorporate effects into an iterative statistical reconstruction. here, we propose new maximum likelihood expectation maximization (mlem) ...