background: in myocardial perfusion spect imaging, images are degraded by photon attenuation, the distance-dependent collimator, detector response and photons scatter. filters greatly affect quality of nuclear medicine images materials and methods: a phantom simulating heart left ventricle was built. about 1mci of 99mtc was injected into the phantom. images were taken from this phantom. some fi...

A Hamming compatible metric is an integer-valued metric on the words of a finite alphabet which agrees with the usual Hamming distance for words of equal length. We define a new Hamming compatible metric, compute the cardinality of a sphere with respect to this metric, and show this metric is minimal in the class of all “well-behaved” Hamming compatible metrics.

We study a special case of Hamming-Huffman trees, in which both data compression and error detection are tackled on the same structure. Given hypercube Q n dimension , we interested some aspects its vertex neighborhoods. For subset L vertices neighborhood is defined as union neighborhoods . The minimum problem that determining cardinality over all those sets This well-known has already been sol...

Similarity search is crucial to many applications. Of particular interest are two flavors of the Hamming distance range query, namely, the Hamming select and the Hamming join (Hamming-select and Hamming-join, respectively). Hamming distance is widely used in approximate near neighbor search for high dimensional data, such as images and document collections. For example, using predefined similar...

In this paper, a new class of frequency hopping sequences (FHSs) of length p is constructed by using Ding-Helleseth generalized cyclotomic classes of order 2, of which the Hamming autoand crosscorrelation functions are investigated (for the Hamming cross-correlation, only the case p ≡ 3 (mod 4) is considered). It is shown that the set of the constructed FHSs is optimal with respect to the avera...