The processing complexity of optimal receivers in frequency selective channels grows exponentially with the channel memory length. Linear receivers, alternatively, offer significantly less complexity with the cost of performance degradation. Such degradation can be due to not fully capturing the inherent frequency diversity or degraded coding gain. In this paper we investigate how effectively t...

In this paper we revisit the notion of sophistication for infinite sequences. Koppel defined sophistication of an object as the length of the shortest (finite) total program (p) that with some (finite or infinite) data (d) produce it and |p|+ |d| is smaller than the shortest description of the object plus a constant. However the notion of “description of infinite sequences” is not appropriately...

In a recent paper, Altenbernd, Thomas and Wöhrle have considered acceptance of languages of infinite two-dimensional words (infinite pictures) by finite tiling systems, with the usual acceptance conditions, such as the Büchi and Muller ones, firstly used for infinite words. The authors asked for comparing the tiling system acceptance with an acceptance of pictures row by row using an automaton ...

The energies of plectonemic and toroidal supercoiled DNA are calculated by treating DNA as an elastic rod with a finite radius. End effects are ignored and all extensive quantities (e.g., writhe, bend energy) are treated as linear densities (writhe per unit length, bend energy per unit length). Minimum energy configurations are found. For plectonemic DNA, the superhelical pitch angle cz is in t...

We present a new recursive generation algorithm for prefix normal words. These are binary strings with the property that no substring has more 1s than the prefix of the same length. The new algorithm uses two operations on binary strings, which exploit certain properties of prefix normal words in a smart way. We introduce infinite prefix normal words and show that one of the operations used by ...

The first order quantum correction to the power of spontaneous radiation of electrons in an arbitrary two-component periodic magnetic field was obtained. The phenomenon of selfpolarization of the spin of electrons in a process of spontaneous radiation was also studied. By electron's motion in a spiral magnetic undulator, the quantitative characteristics of selfpolarization (the polarization deg...

Motivated from the fact that universal source coding on countably infinite alphabets is not feasible, this work introduces the notion of “almost lossless source coding”. Analog to the weak variable-length source coding problem studied by Han [3], almost lossless source coding aims at relaxing the lossless block-wise assumption to allow an average per-letter distortion that vanishes asymptotical...

We show that the number of types of sequences of tuples of a fixed length can be calculated from the number of 1-types and the length of the sequences. Specifically, if κ ≤ λ, then sup |A|=λ |S(A)| = (