New blind source estimation methods based on constant modulus criterion

This thesis presents two novel algorithms for blind chancel equalization (BCE) and blind source separation (BSS). Beside these, a general framework for global convergent analysis is proposed. Finally, the open problem of equalising a non-irreducible system is answered by the algorithm proposed in this thesis.

Semiotic, rhetoric and democracy

This paper unites Deely’s call for a better understanding of semiotics with Jaeger’s insight into the sophists and the cultural history of the Ancient Greeks. The two bodies of knowledge are brought together to try to better understand the importance of rhetorical processes to political forms such as democracy. Jaeger explains how cultural expression, particularly poetry, changed through the archaic and classical eras to deliver, or at least to be commensurate with contemporary politics and ideologies. He explains how Plato (429-347 BCE) struggled against certain poetry and prose manifestations in his ambition to create a ‘perfect man’ – a humanity which would think in a way which would enable the ideal Republic to flourish. Deely’s approach based on Poinsot and Peirce presents a theoretical framework by means of which we can think of the struggle to influence individual and communal conceptualisation as a struggle within semiotics. This is a struggle over the ways reality is signified by signs. Signs are physical and mental indications which, in the semiotic tradition, are taken to produce human subjectivity – human ‘being’. Deely’s extensive body of work is about how these signs are the building blocks of realist constructions of understanding. This paper is concerned with the deliberate use of oral and written signs in rhetorical activity which has been deliberately crafted to change subjectivity. We discuss: (1) what thought and culture is in terms of semiotics and (2) Jaeger’s depiction of Ancient Greece as an illustration of the conjunction between culture and subjectivity. These two fields are brought together in order to make the argument that rhetoric can be theorised as the deliberate harnessing of semiotic affects. The implication is that the same semiotic, subjectivity-changing potency holds for 21st century rhetoric. However fourth century BCE Athens is the best setting for a preliminary discussion of rhetoric as deliberate semiotic practice because this was when rhetoric was most clearly understood for what it is. By contrast a discussion concentrating on modern rhetoric: public relations; advertising; lobbying; and public affairs would open wider controversies requiring considerably more complex explanation.