Ground state wave functions of the halo nuclei 6 He and 8 He have been determined by a genetic algorithm in the framework of the refined resonating group model. The genetic algorithm allows one to apply the underlying variational principle to very complex wave functions and to extract their most important structures in order to give a physical interpretation. The spectrum of the particle unstable isotopes Aϩ1 He Nϩ1 has been determined from the phase shifts of neutron scattering on the particle stable nuclei A He N . Stepwise going on, using the same NN potential in the refined resonating group method bound state and scattering calculation, yielded a consistent description of the nuclei 4,5,6,7,8 He.

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Abstract. Steganography plays an important role in the field of secret communication. The security of such communication lies in the impossibility of proving that secret communication is taking place.We evaluate the implementation of a previously published spread spectrum technique for steganography in auditive media. We have unveiled and solved several weaknesses that compromise undetectability.The spread-spectrum approach of the technique under evaluation is rather unusual for steganography and makes the secret message fit to survive A/D and D/A conversions of analogue audio telephony, re-encoded speech channels of GSM/UMTS, or VoIP. Its impact to signal statistics, which is at least concealed by the lossy channel, is reduced. There is little published on robust audio steganography, its steganalysis, and evaluation, with the possible exception of audio watermarking, where undetectability is not as important.

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