On the synthesis of all-pass digital transfer functions based on LBR two-pair extraction procedure†

In this paper a simple explicit expression is provided for the parameter a in LBR two-pairs used in the synthesis of all-pass digital transfer functions. The result can be of interest in automated procedures for digital filter design. Further, canonical realizations for this type of two-pairs are given.     

Autonomous operator management for evolutionary algorithms

The performance of an evolutionary algorithm strongly depends on the design of its operators and on the management of these operators along the search; that is, on the ability of the algorithm to balance exploration and exploitation of the search space. Recent approaches automate the tuning and control of the parameters that govern this balance. We propose a new technique to dynamically control the behavior of operators in an EA and to manage a large set of potential operators. The best operators are rewarded by applying them more often. Tests of this technique on instances of 3-SAT return results that are competitive with an algorithm tailored to the problem.     

Resampling the output of switched networks†

The use of switches has given the engineers a new tool for modifying the characteristic of networks. Their use is usually that of a modulating process, i.e. to convert the signal wave into a series of amplitude-modulated pulses which are then further handled by a suitable network, usually a filter. The possibility of resampling the output has been investigated; it was found that the phase angle of the second sampler with respect to the first has a significant effect on both the phase and the magnitude of the time function that can be reproduced from the output of the second sampler.     

Cryptanalysis of MD2

This paper considers the hash function MD2 which was developed by Ron Rivest in 1989. Despite its age, MD2 has withstood cryptanalytic attacks until recently. This paper contains the state-of-the-art cryptanalytic results on MD2, in particular collision and preimage attacks on the full hash function, the latter having complexity 2⁷³, which should be compared to a brute-force attack of complexity 2¹²⁸.